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Rauber S, Mohammadian H, Schmidkonz C, Atzinger A, Soare A, Treutlein C, Kemble S, Mahony CB, Geisthoff M, Angeli MR, Raimondo MG, Xu C, Yang KT, Lu L, Labinsky H, Saad MSA, Gwellem CA, Chang J, Huang K, Kampylafka E, Knitza J, Bilyy R, Distler JHW, Hanlon MM, Fearon U, Veale DJ, Roemer FW, Bäuerle T, Maric HM, Maschauer S, Ekici AB, Buckley CD, Croft AP, Kuwert T, Prante O, Cañete JD, Schett G, Ramming A. CD200 + fibroblasts form a pro-resolving mesenchymal network in arthritis. Nat Immunol 2024; 25:682-692. [PMID: 38396288 DOI: 10.1038/s41590-024-01774-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 01/30/2024] [Indexed: 02/25/2024]
Abstract
Fibroblasts are important regulators of inflammation, but whether fibroblasts change phenotype during resolution of inflammation is not clear. Here we use positron emission tomography to detect fibroblast activation protein (FAP) as a means to visualize fibroblast activation in vivo during inflammation in humans. While tracer accumulation is high in active arthritis, it decreases after tumor necrosis factor and interleukin-17A inhibition. Biopsy-based single-cell RNA-sequencing analyses in experimental arthritis show that FAP signal reduction reflects a phenotypic switch from pro-inflammatory MMP3+/IL6+ fibroblasts (high FAP internalization) to pro-resolving CD200+DKK3+ fibroblasts (low FAP internalization). Spatial transcriptomics of human joints indicates that pro-resolving niches of CD200+DKK3+ fibroblasts cluster with type 2 innate lymphoid cells, whereas MMP3+/IL6+ fibroblasts colocalize with inflammatory immune cells. CD200+DKK3+ fibroblasts stabilized the type 2 innate lymphoid cell phenotype and induced resolution of arthritis via CD200-CD200R1 signaling. Taken together, these data suggest a dynamic molecular regulation of the mesenchymal compartment during resolution of inflammation.
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Affiliation(s)
- Simon Rauber
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Hashem Mohammadian
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Christian Schmidkonz
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Department of Industrial Engineering and Health, Technical University Amberg-Weiden, Institute of Medical Engineering, Weiden, Germany
| | - Armin Atzinger
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Alina Soare
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Christoph Treutlein
- Institute of Radiology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Samuel Kemble
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- NIHR Birmingham Biomedical Research Center and Clinical Research Facility, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Christopher B Mahony
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- NIHR Birmingham Biomedical Research Center and Clinical Research Facility, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Manuel Geisthoff
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Mario R Angeli
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Maria G Raimondo
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Cong Xu
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Kai-Ting Yang
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Le Lu
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Hannah Labinsky
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Mina S A Saad
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Charles A Gwellem
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Jiyang Chang
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Kaiyue Huang
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Eleni Kampylafka
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Johannes Knitza
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Rostyslav Bilyy
- Department of Histology, Cytology, Embryology, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
- Institute of Cellular Biology and Pathology 'Nicolae Simionescu', Bucharest, Romania
| | - Jörg H W Distler
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Clinic for Rheumatology, University Hospital Düsseldorf, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- Hiller Research Center, University Hospital Düsseldorf, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Megan M Hanlon
- Molecular Rheumatology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Ursula Fearon
- Molecular Rheumatology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Douglas J Veale
- EULAR Centre for Arthritis & Rheumatic Diseases, St. Vincent's University Hospital, University College Dublin, Dublin, Ireland
| | - Frank W Roemer
- Institute of Radiology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Tobias Bäuerle
- Institute of Radiology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Hans M Maric
- Rudolf-Virchow-Center for Integrative and Translational Imaging, University of Würzburg, Würzburg, Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Arif B Ekici
- Institute of Human Genetics, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | | | - Adam P Croft
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- NIHR Birmingham Biomedical Research Center and Clinical Research Facility, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Torsten Kuwert
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | | | - Georg Schett
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Andreas Ramming
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany.
- Deutsches Zentrum für Immuntherapie (DZI), Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany.
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Ruopp M, Zhu S, Worschech R, Haas D, Maschauer S, Prante O, Meinel L, Lühmann T. Bioconjugation of a Fibroblast Activation Protein Targeted Interleukin-4. ACS Biomater Sci Eng 2023; 9:5580-5588. [PMID: 37721169 DOI: 10.1021/acsbiomaterials.3c00879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
Interleukin-4 (IL-4) is an immune-modulating therapeutic with growing potential for the treatment of inflammatory diseases. Current challenges of IL-4 therapy include a low serum half-life and pleiotropic activity, suggesting effective targeting of IL-4. To develop an interleukin-4 bioconjugate with rapid targeting to inflammatory disease sites, we report the chemical synthesis, bioconjugation, and in vitro characterization of a murine interleukin-4 (mIL-4) conjugate decorated with a fibroblast activation protein inhibitor (FAPI). The FAPI targeting moiety features 2,2',2″,2‴-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid (DOTA) to allow future biodistribution and imaging studies of the FAPI-mIL-4 bioconjugate. We demonstrated site-specific coupling of mIL-4 and FAPI-DOTA deploying chemo-enzyme and enzyme chemistries with a high purity exceeding 95%. The FAPI-DOTA modified mIL-4 was bioactive with polarization of murine macrophages into the M2 state while maintaining specific binding to FAP on fibroblast cells. Together, these results point to future in vivo use of the FAPI-mIL-4 bioconjugate to assess biodistribution and biological effects in animal models of inflammatory joint disease.
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Affiliation(s)
- Matthias Ruopp
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Sha Zhu
- Department of Nuclear Medicine, Translational Research Center, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
| | - Rafael Worschech
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Dorothee Haas
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Translational Research Center, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Translational Research Center, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
| | - Lorenz Meinel
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
- Helmholtz Institute for RNA-Based Infection Research (HIRI), Helmholtz Center for Infection Research (HZI), 97080 Würzburg, Germany
| | - Tessa Lühmann
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
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3
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Krug J, Rodrian G, Petter K, Yang H, Khoziainova S, Guo W, Bénard A, Merkel S, Gellert S, Maschauer S, Spermann M, Waldner M, Bailey P, Pilarsky C, Liebl A, Tripal P, Christoph J, Naschberger E, Croner R, Schellerer VS, Becker C, Hartmann A, Tüting T, Prante O, Grützmann R, Grivennikov SI, Stürzl M, Britzen-Laurent N. N-glycosylation Regulates Intrinsic IFN-γ Resistance in Colorectal Cancer: Implications for Immunotherapy. Gastroenterology 2023; 164:392-406.e5. [PMID: 36402190 PMCID: PMC10009756 DOI: 10.1053/j.gastro.2022.11.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND & AIMS Advanced colorectal carcinoma (CRC) is characterized by a high frequency of primary immune evasion and refractoriness to immunotherapy. Given the importance of interferon (IFN)-γ in CRC immunosurveillance, we investigated whether and how acquired IFN-γ resistance in tumor cells would promote tumor growth, and whether IFN-γ sensitivity could be restored. METHODS Spontaneous and colitis-associated CRC development was induced in mice with a specific IFN-γ pathway inhibition in intestinal epithelial cells. The influence of IFN-γ pathway gene status and expression on survival was assessed in patients with CRC. The mechanisms underlying IFN-γ resistance were investigated in CRC cell lines. RESULTS The conditional knockout of the IFN-γ receptor in intestinal epithelial cells enhanced spontaneous and colitis-associated colon tumorigenesis in mice, and the loss of IFN-γ receptor α (IFNγRα) expression by tumor cells predicted poor prognosis in patients with CRC. IFNγRα expression was repressed in human CRC cells through changes in N-glycosylation, which decreased protein stability via proteasome-dependent degradation, inhibiting IFNγR-signaling. Downregulation of the bisecting N-acetylglucosaminyltransferase III (MGAT3) expression was associated with IFN-γ resistance in all IFN-γ-resistant cells, and highly correlated with low IFNγRα expression in CRC tissues. Both ectopic and pharmacological reconstitution of MGAT3 expression with all-trans retinoic acid increased bisecting N-glycosylation, as well as IFNγRα protein stability and signaling. CONCLUSIONS Together, our results demonstrated that tumor-associated changes in N-glycosylation destabilize IFNγRα, causing IFN-γ resistance in CRC. IFN-γ sensitivity could be reestablished through the increase in MGAT3 expression, notably via all-trans retinoic acid treatment, providing new prospects for the treatment of immune-resistant CRC.
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Affiliation(s)
- Julia Krug
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Gabriele Rodrian
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Katja Petter
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Hai Yang
- Division of Surgical Research, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Svetlana Khoziainova
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania; Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Wei Guo
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania
| | - Alan Bénard
- Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Susanne Merkel
- Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Susan Gellert
- Laboratory of Experimental Dermatology, Department of Dermatology, University Hospital and Health Campus Immunology Infectiology and Inflammation (GC-I3), Otto-von-Guericke-University, Magdeburg, Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Monika Spermann
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Maximilian Waldner
- Department of Medicine I, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Peter Bailey
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Christian Pilarsky
- Division of Surgical Research, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Andrea Liebl
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Philipp Tripal
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Jan Christoph
- Department of Medical Informatics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Tennenlohe, Germany
| | - Elisabeth Naschberger
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Roland Croner
- Department of General, Visceral, Vascular and Transplant Surgery, University Hospital Magdeburg, Otto-von-Guericke-University, Magdeburg, Germany
| | - Vera S Schellerer
- Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Christoph Becker
- Department of Medicine I, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Arndt Hartmann
- Department of Pathology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Thomas Tüting
- Laboratory of Experimental Dermatology, Department of Dermatology, University Hospital and Health Campus Immunology Infectiology and Inflammation (GC-I3), Otto-von-Guericke-University, Magdeburg, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Robert Grützmann
- Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Sergei I Grivennikov
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania; Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Michael Stürzl
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany; Comprehensive Cancer Center Erlangen-EMN, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Nathalie Britzen-Laurent
- Division of Molecular and Experimental Surgery, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany; Division of Surgical Research, Department of Surgery, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
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Treutlein C, Distler JHW, Tascilar K, Fakhouri SC, Györfi AH, Atzinger A, Matei AE, Dees C, Büttner-Herold M, Kuwert T, Prante O, Bäuerle T, Uder M, Schett G, Schmidkonz C, Bergmann C. Assessment of myocardial fibrosis in patients with systemic sclerosis using [68Ga]Ga-FAPI-04-PET-CT. Eur J Nucl Med Mol Imaging 2022; 50:1629-1635. [PMID: 36522438 PMCID: PMC10119041 DOI: 10.1007/s00259-022-06081-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/03/2022] [Indexed: 12/23/2022]
Abstract
Abstract
Purpose
Myocardial fibrosis (MF) is a factor of poor prognosis in systemic sclerosis (SSc). Direct in-vivo visualization of fibroblast activation as early readout of MF has not been feasible to date. Here, we characterize 68Gallium-labeled-Fibroblast-Activation-Inhibitor-04 ([68Ga]Ga-FAPI-04)-PET-CT as a diagnostic tool in SSc-related MF.
Methods
In this proof-of-concept trial, six SSc patients with and eight without MF of the EUSTAR cohort Erlangen underwent [68Ga]Ga-FAPI-04-PET-CT and cardiac MRI (cMRI) and clinical and serologic investigations just before baseline and during follow-up between January 2020 and December 2020. Myocardial biopsy was performed as clinically indicated.
Results
[68Ga]Ga-FAPI-04 tracer uptake was increased in SSc-related MF with higher uptake in SSc patients with arrhythmias, elevated serum-NT-pro-BNP, and increased late gadolinium enhancement (LGE) in cMRI. Histologically, myocardial biopsies from cMRI- and [68Ga]Ga-FAPI-04-positive regions confirmed the accumulation of FAP+ fibroblasts surrounded by collagen deposits. We observed similar but not equal spatial distributions of [68Ga]Ga-FAPI-04 uptake and quantitative cMRI-based techniques. Using sequential [68Ga]Ga-FAPI-04-PET-CTs, we observed dynamic changes of [68Ga]Ga-FAPI-04 uptake associated with changes in the activity of SSc-related MF, while cMRI parameters remained stable after regression of molecular activity and rather indicated tissue damage.
Conclusions
We present first in-human evidence that [68Ga]Ga-FAPI-04 uptake visualizes fibroblast activation in SSc-related MF and may be a diagnostic option to monitor cardiac fibroblast activity in situ.
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Schindler L, Wohlfahrt K, Gluhacevic von Krüchten L, Prante O, Keller M, Maschauer S. Neurotensin analogs by fluoroglycosylation at N ω-carbamoylated arginines for PET imaging of NTS1-positive tumors. Sci Rep 2022; 12:15028. [PMID: 36056076 PMCID: PMC9440028 DOI: 10.1038/s41598-022-19296-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 08/26/2022] [Indexed: 11/20/2022] Open
Abstract
Since neurotensin (NT) receptors of subtype-1 (NTS1) are expressed by different types of malignant tumors, such as pancreatic adenocarcinoma, colorectal and prostate carcinoma, they represent an interesting target for tumor imaging by positron emission tomography (PET) and endoradiotherapy. Previously reported neurotensin-derived NTS1 ligands for PET were radiolabeled by modification and prelongation of the N-terminus of NT(8-13) peptide analogs. In this study, we demonstrate that modifying Arg8 or Arg9 by Nω-carbamoylation and subsequent fluoroglycosylation provides a suitable approach for the development of NT(8-13) analogs as PET imaging agents. The Nω-carbamoylated and fluoroglycosylated NT(8-13) analogs retained high NTS1 affinity in the one-digit nanomolar range as well as high metabolic stability in vitro. In vivo, the radioligand [18F]21 demonstrated favorable biokinetics in HT-29 tumor-bearing mice with high tumor uptake and high retention, predominantly renal clearance, and fast wash-out from blood and other non-target tissues. Therefore, [18F]21 has the potential to be used as molecular probe for the imaging of NTS1-expressing tumors by PET.
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Affiliation(s)
- Lisa Schindler
- Faculty of Chemistry and Pharmacy, Institute of Pharmacy, University of Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
| | - Katrin Wohlfahrt
- Faculty of Chemistry and Pharmacy, Institute of Pharmacy, University of Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
- Hennig Arzneimittel GmbH & Co KG, Liebigstr. 1-2, 65439, Flörsheim am Main, Germany
| | - Lara Gluhacevic von Krüchten
- Faculty of Chemistry and Pharmacy, Institute of Pharmacy, University of Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Schwabachanlage 12, 91054, Erlangen, Germany
| | - Max Keller
- Faculty of Chemistry and Pharmacy, Institute of Pharmacy, University of Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany.
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Schwabachanlage 12, 91054, Erlangen, Germany.
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Schmidkonz C, Rauber S, Raimondo MG, Labinsky H, Atzinger A, Treutlein C, Knitza J, Maschauer S, Roemer F, Prante O, Kuwert T, Cañete JDD, Schett G, Ramming A. OP0256 FIBROBLAST ACTIVATION PROTEIN (FAP) PET-CT IMAGING ALLOWS TO DEPICT INFLAMMATORY JOINT REMODELING IN PATIENTS WITH PSORIATIC ARTHRITIS. Ann Rheum Dis 2022. [DOI: 10.1136/annrheumdis-2022-eular.3963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BackgroundPsoriatic arthritis (PsA) is characterized by substantial mesenchymal tissue activation in the context of inflammation leading to structural damage. Measuring mesenchymal tissue activation in humans in vivo is challenging but may represent a possibility to detect regions at risk for structural damage. Recently, theranostic ligands have been developed that selectively bind Fibroblast Activation Protein (FAP) and allow recognition of activated mesenchymal cells in vivo. Accumulation of such FAP-based tracers can be visualized by positron-emission tomography (PET) (1).ObjectivesIn this study, we analyzed whether FAP tracer-based PET-CT can detect mesenchymal tissue activation in patients with PsA and whether this signal is associated with joint damage.Methods120 consecutive PsA patients fulfilling CASPAR criteria and 100 healthy controls without musculoskeletal disease received full-body PET-CT investigation using a 68Ga-labelled FAP inhibitor (68Ga-FAPI-04) tracer, specifically binding FAP. For all visually identified pathological tracer-positive lesions the mean and maximum standardized uptake value (SUV mean, SUV max) was assessed. Tracer uptake was quantified in peripheral and axial joints and correlated to various composite scores of PsA. Hand MRI scans were performed in parallel to assess inflammation and structural lesions. Follow-up 68Ga-FAPI-04 PET-CT scans were obtained in a subset of patients treated with cytokine inhibitors (follow-up between 3-6 months) to assess joint damage over time. In addition, FAP related tissue responses in synovial biopsy samples were evaluated on a molecular level by high-resolution slide RNA-sequencing in a subset of patients.Results68Ga-FAPI-04 accumulated at synovial and enthesial sites in patients with PsA compared to healthy controls (p < 0.0001). Active pain in peripheral as well as axial joints as measured on a visual analogue scale highly correlated with an increased 68Ga-FAPI-04 uptake (peripheral pain: R = 0.718, p < 0.0001; back pain: R = 0.875, p < 0.0001). Disease Activity in PSoriatic Arthritis (DAPSA) score also correlated with the SUV mean and SUV max of FAP expression (R = 0.774; p = 0.0001). Increased 68Ga-FAPI-04 uptake at baseline was associated with progression of joint damage 3-6 months later as assessed by PsAMRIS score (R = 0.778, p < 0.0001). Treatment with cytokine inhibitors partially reduced FAP expression which was associated with arrest of joint damage in MRI. In contrast, persistent FAP expression was associated with a rapid progression of joint damage in MRI. Molecular analysis of synovial biopsy samples from FAP+ lesions revealed interactions between FAP+ fibroblasts and T cells, innate lymphoid cells and macrophages, which was correlated to a strong upregulation of NF-kB related pathways fostering cartilage and bone destruction.ConclusionOur study presents the first in-human evidence that fibroblast activation correlates with disease progression and joint damage in patients with PsA. FAP related imaging might therefore improve the risk assessment of rapidly emerging joint damage in PsA and open new options of treat-to-target strategies in PsA.References[1]Schmidkonz C, Rauber S, Atzinger A, Agarwal R, Gotz TI, Soare A, Cordes M, Prante O, Bergmann C, Kleyer A, Agaimy A, Kuwert T, Schett G, Ramming A, Disentangling inflammatory from fibrotic disease activity by fibroblast activation protein imaging. Ann. Rheum. Dis. 79 (2020), 1485-1491.Disclosure of InterestsNone declared
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Bolik KV, Shinde S, Riss P, Maschauer S, Prante O. Copper-mediated 18F-fluorination of boroxines: a systematic optimization study. Nucl Med Biol 2022. [DOI: 10.1016/s0969-8051(22)00111-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kuwert T, Schmidkonz C, Prante O, Schett G, Ramming A. FAPI-PET Opens a New Window for Understanding of Immune-Mediated Inflammatory Diseases. J Nucl Med 2022; 63:1136-1137. [PMID: 35393350 DOI: 10.2967/jnumed.122.263922] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 03/30/2022] [Indexed: 11/16/2022] Open
Abstract
In vivo visualization of inflammatory lesions in the body has been revolutionized by positron emission tomography (PET) with F-18-deoxyglucose (FDG) as a tracer and by magnetic resonance imaging (MRI) with gadolinium-labelled contrast media. Apart from other indications, FDG-PET and MRI have substantially improved the diagnosis and monitoring of immune-mediated inflammatory diseases such as arthritis and connective tissue diseases. While the visualization of active inflammation is well established, the detection of tissue response and tissue remodelling processes, which accompany immune-mediated inflammatory diseases (IMIDs) and lead to organ damage, is not well established. Tissue remodelling processes during inflammation are based on mesenchymal stroma cell activation and expansion in parenchymatous organs or the synovial membrane of inflamed joints. These cells express specific markers, such as fibroblast activation protein (FAP), that can be visualized by radiolabelled compounds (e.g. FAP inhibitors; FAPI) using PET. First evidence shows that focal accumulation of FAPI tracer, indicating active tissue remodelling, is observed in patients with IMIDs that are characterized by a combination of chronic inflammation and tissue responses, such as systemic sclerosis, IgG4 syndrome, or spondyloarthritis. Such FAPI-positive remodelling lesions are not always FDG-positive indicating that inflammation and tissue responses can be disentangled by such methods. These data suggest that tracers such as FAPI allow to visualize the dynamics of tissue responses in immune-mediated inflammatory diseases in vivo. This development opens new options for early recognition of tissue remodelling in the context of chronic inflammation.
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Affiliation(s)
- Torsten Kuwert
- Clinic of Nuclear Medicine, University Hospital Erlangen, Germany
| | | | - Olaf Prante
- Clinic of Nuclear Medicine, University Hospital Erlangen, Germany
| | - Georg Schett
- Clinic of Nuclear Medicine, University Hospital Erlangen, Germany
| | - Andreas Ramming
- Clinic of Nuclear Medicine, University Hospital Erlangen, Germany
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Gizem Özkan H, Toms J, Maschauer S, Prante O, Mokhir A. Aminoferrocene‐Based Anticancer Prodrugs Labelled with Cyanine Dyes for in vivo Imaging. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100829] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Hülya Gizem Özkan
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) Department of Chemistry and Pharmacy, Organic Chemistry Chair II Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Johannes Toms
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Schwabachanlage 12 91054 Erlangen Germany
| | - Simone Maschauer
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Schwabachanlage 12 91054 Erlangen Germany
| | - Olaf Prante
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Schwabachanlage 12 91054 Erlangen Germany
| | - Andriy Mokhir
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) Department of Chemistry and Pharmacy, Organic Chemistry Chair II Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
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Bock L, Schultheiß SK, Maschauer S, Lasch R, Gradl S, Prante O, Zard SZ, Heinrich MR. Synthesis of 2‐(Chlorodifluoromethyl)indoles for Nucleophilic Halogen Exchange with [
18
F]Fluoride. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Leonard Bock
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Stefanie K. Schultheiß
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Schwabachanlage 12 91054 Erlangen Germany
| | - Roman Lasch
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Susanne Gradl
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Schwabachanlage 12 91054 Erlangen Germany
| | - Samir Z. Zard
- Laboratoire de Synthèse Organique associé au CNRS Ecole Polytechnique 91128 Palaiseau France
| | - Markus R. Heinrich
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
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Budzinski J, Maschauer S, Kobayashi H, Couvineau P, Vogt H, Gmeiner P, Roggenhofer A, Prante O, Bouvier M, Weikert D. Bivalent ligands promote endosomal trafficking of the dopamine D3 receptor-neurotensin receptor 1 heterodimer. Commun Biol 2021; 4:1062. [PMID: 34508168 PMCID: PMC8433439 DOI: 10.1038/s42003-021-02574-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 08/18/2021] [Indexed: 02/08/2023] Open
Abstract
Bivalent ligands are composed of two pharmacophores connected by a spacer of variable size. These ligands are able to simultaneously recognize two binding sites, for example in a G protein-coupled receptor heterodimer, resulting in enhanced binding affinity. Taking advantage of previously described heterobivalent dopamine-neurotensin receptor ligands, we demonstrate specific interactions between dopamine D3 (D3R) and neurotensin receptor 1 (NTSR1), two receptors with expression in overlapping brain areas that are associated with neuropsychiatric diseases and addiction. Bivalent ligand binding to D3R-NTSR1 dimers results in picomolar binding affinity and high selectivity compared to the binding to monomeric receptors. Specificity of the ligands for the D3R-NTSR1 receptor pair over D2R-NTSR1 dimers can be achieved by a careful choice of the linker length. Bivalent ligands enhance and stabilize the receptor-receptor interaction leading to NTSR1-controlled internalization of D3R into endosomes via recruitment of β-arrestin, highlighting a potential mechanism for dimer-specific receptor trafficking and signalling.
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Affiliation(s)
- Julian Budzinski
- grid.5330.50000 0001 2107 3311Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Simone Maschauer
- grid.5330.50000 0001 2107 3311Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Hiroyuki Kobayashi
- grid.14848.310000 0001 2292 3357Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC Canada
| | - Pierre Couvineau
- grid.14848.310000 0001 2292 3357Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC Canada
| | - Hannah Vogt
- grid.5330.50000 0001 2107 3311Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Peter Gmeiner
- grid.5330.50000 0001 2107 3311Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Anna Roggenhofer
- grid.5330.50000 0001 2107 3311Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Olaf Prante
- grid.5330.50000 0001 2107 3311Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Michel Bouvier
- grid.14848.310000 0001 2292 3357Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC Canada
| | - Dorothee Weikert
- grid.5330.50000 0001 2107 3311Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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Shinde SS, Bolik KV, Maschauer S, Prante O. 18F-Fluorination Using Tri- Tert-Butanol Ammonium Iodide as Phase-Transfer Catalyst: An Alternative Minimalist Approach. Pharmaceuticals (Basel) 2021; 14:ph14090833. [PMID: 34577533 PMCID: PMC8465076 DOI: 10.3390/ph14090833] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 12/21/2022] Open
Abstract
The 18F syntheses of tracers for positron emission tomography (PET) typically require several steps, including extraction of [18F]fluoride from H2[18O]O, elution, and drying, prior to nucleophilic substitution reaction, being a laborious and time-consuming process. The elution of [18F]fluoride is commonly achieved by phase transfer catalysts (PTC) in aqueous solution, which makes azeotropic drying indispensable. The ideal PTC is characterized by a slightly basic nature, its capacity to elute [18F]fluoride with anhydrous solvents, and its efficient complex formation with [18F]fluoride during subsequent labeling. Herein, we developed tri-(tert-butanol)-methylammonium iodide (TBMA-I), a quaternary ammonium salt serving as the PTC for 18F-fluorination reactions. The favorable elution efficiency of [18F]fluoride using TBMA-I was demonstrated with aprotic and protic solvents, maintaining high 18F-recoveries of 96-99%. 18F-labeling reactions using TBMA-I as PTC were studied with aliphatic 1,3-ditosylpropane and aryl pinacol boronate esters as precursors, providing 18F-labeled products in moderate-to-high radiochemical yields. TBMA-I revealed adequate properties for application to 18F-fluorination reactions and could be used for elution of [18F]fluoride with MeOH, omitting an additional base and azeotropic drying prior to 18F-labeling. We speculate that the tert-alcohol functionality of TBMA-I promotes intermolecular hydrogen bonding, which enhances the elution efficiency and stability of [18F]fluoride during nucleophilic 18F-fluorination.
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Bäuerle T, Gupta S, Zheng S, Seyler L, Leporati A, Marosfoi M, Maschauer S, Prante O, Caravan P, Bogdanov A. Multimodal Bone Metastasis-associated Epidermal Growth Factor Receptor Imaging in an Orthotopic Rat Model. Radiol Imaging Cancer 2021; 3:e200069. [PMID: 34170199 DOI: 10.1148/rycan.2021200069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Purpose To develop multimodality imaging techniques for measuring epidermal growth factor receptor (EGFR) as a therapy-relevant and metastasis-associated molecular marker in triple-negative mammary adenocarcinoma metastases. Materials and Methods An orthotopic bone metastasis EGFR-positive, triple-negative breast cancer (TNBC) model in rats was used for bioluminescence imaging, SPECT/CT, PET/CT, and MRI with quantitative analysis of transcripts (n = 22 rats). Receptor-specific MRI of EGFR expression in vivo was performed by acquiring spin-echo T1-weighted images after sequential administration of a pair of anti-EGFR antigen binding fragments, F(ab')2, conjugated to either horseradish peroxidase or glucose oxidase, which have complementing activities, as well as paramagnetic (gadolinium[III]-mono-5-hydroxytryptamide of 2,2',2''-(10-(2,6-dioxotetrahydro-2H-pyran-3-yl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid, or Gd-5HT-DOTAGA) or positron-emitting (gallium 68-5HT-DOTAGA) substrates for MRI and PET/CT imaging, respectively. EGFR expression was confirmed by quantitative reverse transcriptase polymerase chain reaction and immunohistochemical analyses to compare with image findings. Results After surgical intraarterial delivery of TNBC cells, rats developed tumors that diverged into either rapidly growing osteolytic or slow-growing nonosteolytic tumors. Both tumor types showed receptor-specific initial MRI signal enhancement (contrast-to-noise ratio) that was three to six times higher than that of normal bone marrow (29.4 vs 4.9; P < .01). Micro PET/CT imaging of EGFR expression demonstrated a high level of heterogeneity with regional uptake of the tracer, which corresponded to region-of-interest MRI signal intensity elevation (121.1 vs 93.3; P < .001). Analysis of metastases with corroboration of imaging results showed high levels of EGFR protein and messenger RNA, or mRNA, expression in the invasive tumor. Conclusion Convergence of multimodal molecular receptor imaging enabled comprehensive assessment of EGFR overexpression in an orthotopic model of TNBC metastasis. Keywords: Animal Studies, Molecular Imaging-Cancer, MR-Contrast Agent, Radionuclide Studies, Skeletal-Appendicular, Metastases Supplemental material is available for this article. © RSNA, 2021.
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Affiliation(s)
- Tobias Bäuerle
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Suresh Gupta
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Shaokuan Zheng
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Lisa Seyler
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Anita Leporati
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Miklos Marosfoi
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Simone Maschauer
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Olaf Prante
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Peter Caravan
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
| | - Alexei Bogdanov
- From the Institute of Radiology, Friedrich-Alexander University of Erlangen-Nurnberg, Erlangen, Germany (T.B., L.S.); Laboratory of Molecular Imaging Probes, Department of Radiology (S.G., A.L., A.B.), and Advanced MRI Center and New England Center for Stroke Research, Department of Radiology (S.Z., M.M.), University of Massachusetts Medical School, 55 Lake Ave North, S6-434, Worcester, MA 01655; Department of Nuclear Medicine, Friedrich-Alexander University of Erlangen-Nurnberg, Germany (S.M., O.P.); A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass (P.C.); and A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russian Federation (A.B.)
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Bergmann C, Distler JHW, Treutlein C, Tascilar K, Mueller AT, Atzinger A, Matei AE, Knitza J, Györfi AH, Lueck A, Dees C, Soare A, Ramming A, Schönau V, Distler O, Prante O, Ritt P, Goetz TI, Koehner M, Cordes M, Baeuerle T, Kuwert T, Schett G, Schmidkonz C. OP0272 68GA-FAPI-04 PET/CT STUDY EXTENSION FOR THE ASSESSMENT OF FIBROBLAST ACTIVATION AND RISK EVALUATION IN SYSTEMIC SCLEROSIS-RELATED INTERSTITIAL LUNG DISEASE. Ann Rheum Dis 2021. [DOI: 10.1136/annrheumdis-2021-eular.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Background:Interstitial lung disease (ILD) is the most common cause of death in systemic sclerosis (SSc). To date, the progression of SSc-ILD is judged by the accrual of lung damage on computed tomography (CT) and functional decline (forced vital capacity). However, this approach does not directly assess the activity of tissue remodeling. Moreover, prediction of the course of ILD in individual SSc patients remains challenging. Fibroblast Activation Protein (FAP) is a specific, ex vivo validated marker for activated fibroblasts.Objectives:The aims of this study were: 1. To assess differences in the uptake of 68GA-FAPI 04 in SSc-ILD patients compared to controls, to analyze 2. whether 68GA-FAPI 04 uptake at baseline correlates with other risk factors of disease progression and 3. Whether 68GA-FAPI 04 uptake is associated with the course of SSc-ILD.Methods:Between September 2018 and April 2020, 21 patients with SSc-ILD confirmed by HRCT and onset of SSc-ILD within ≤ 5 years or signs of progressive ILD and 21 controls without ILD were consecutively enrolled. All participants underwent 68Ga-FAPI-04 PET/CT imaging and standard-of-care procedures including HRCT and lung function testing (PFT) at baseline. Patients with SSc-ILD patients were followed-up for 6 months with HRCT and PFT. Follow-up 68Ga-FAPI-04 PET/CT scans were obtained in a subset of patients treated with nintedanib. We compared baseline 68Ga-FAPI-04 PET/CT uptake to standard diagnostic tools and currently used predictors of ILD progression. The association of 68Ga-FAPI-04 uptake with changes in FVC was analyzed using mixed-effects models.Results:68Ga-FAPI-04 accumulated in fibrotic areas of the lungs in SSc-ILD compared to controls with a median (q1-q3 interval) wlSUVmean of 0.8 (0.6 to 2.1) in the SSc-ILD group and 0.5 (0.4 to 0.5) in the control group (p<0.0001 with Mann-Whitney test) and a median whole lung maximal standardized uptake value (wlSUVmax) of 4.4 (3.05 to 5.2) in the SSc-ILD group compared to 0.7 (0.65 to 0.7) in the control group (p<0.0001). wlFAPI-MAV and wlTL-FAPI were not measurable in control subjects, as no 68Ga-FAPI-04 uptake above background level was observed. In the SSc-ILD group the median wlFAPI-MAV was 254cm3 (163.4 to 442.3) and the median wlTL-FAPI was 183.6 cm3 (98.04 to 960.7). 68Ga-FAPI-04 uptake was higher in patients with extensive disease, with previous ILD progression or high EUSTAR activity scores. Increased 68Ga-FAPI-04 uptake at baseline was associated with progression of ILD independently of extent of involvement on HRCT scan and the forced vital capacity at baseline. In consecutive 68Ga-FAPI-04-PET/CTs, changes in 68Ga-FAPI-04 uptake was concordant with the observed response to the fibroblast-targeting antifibrotic agent nintedanib.Conclusion:Our study presents first in human evidence that 68Ga-FAPI-04-fibroblast uptake correlates with fibrotic activity and disease progression in the lungs of SSc-ILD patients and that 68Ga-FAPI-04-PET/CT may be of potential to improve risk assessment of SSc-ILD.Figure 1.A and B:68Ga-FAPI-04 PET/CT scan from a patient with SSc-ILD with selective 68Ga-FAPI-04 uptake in fibrotic areas of the left- and right lower lung lobes (red arrows), but not in non-fibrotic areas such as the middle lobe (green arrow). B Corresponding CT component.Acknowledgements:We gratefully acknowledge Prof. Uwe Haberkorn (University Hospital Heidelberg and DKFZ, Heidelberg, Germany) and iTheranostics Inc. (Dulles, VA, USA) for providing the precursor FAPI-04.Disclosure of Interests:Christina Bergmann: None declared, Jörg H.W. Distler Speakers bureau: Actelion, Anamar, ARXX, Pharma, Boehringer Ingelheim, Celgene, Galapagos, GSK, Inventiva, JB Therapeutics, and UCB, Grant/research support from: Anamar, Active Biotech, Array Biopharma, ARXX, aTyr, BMS, Bayer Pharma, Boehringer Ingelheim, Celgene, Galapagos, GSK, Inventiva, Novartis, Sanofi-Aventis, RedX, UCB, Christoph Treutlein: None declared, Koray Tascilar Speakers bureau: Gilead sciences GmbH, Pfizer Turkey, UCB Turkey, Anna-Theresa Mueller: None declared, Armin Atzinger: None declared, Alexandru-Emil Matei: None declared, Johannes Knitza: None declared, Andrea-Hermina Györfi: None declared, Anja Lueck: None declared, Clara Dees: None declared, Alina Soare: None declared, Andreas Ramming: None declared, Verena Schönau: None declared, Oliver Distler Speakers bureau: Arxx Therapeutics, Baecon Discovery, Blade Therapeutics,Bayer, Böhringer Ingelheim, Catenion,Competitive Drug Development International Ltd, Corbuspharma, CSL Behring, ChemomAb, Horizon Pharmaceuticals, Ergonex, Galaapagos NV, Glenmark Pharmaceuticals,GSK, Inventiva, Italfarmaco, IQvia, Kymera, Lilly, Medac, Medscape, MSD, Novartis, Pfizer, Roche, Sanofi, Taget Bio Sciencec, UCB, Grant/research support from: Bayer,Böhringer Ingelheim, Mitsubishi Tanabe Pharma, Olaf Prante: None declared, Philipp Ritt: None declared, Theresa Ida Goetz: None declared, Markus Koehner: None declared, Michael Cordes: None declared, Tobias Baeuerle: None declared, Torsten Kuwert Speakers bureau: Honoraria for occasional lectures by Siemens Healthineers, Grant/research support from: Research grant to the Clinic of Nuclear Medicine by this entity covering projects in the field of SPECT/CT, Georg Schett: None declared, Christian Schmidkonz: None declared
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Bergmann C, Distler JHW, Treutlein C, Tascilar K, Müller AT, Atzinger A, Matei AE, Knitza J, Györfi AH, Lück A, Dees C, Soare A, Ramming A, Schönau V, Distler O, Prante O, Ritt P, Götz TI, Köhner M, Cordes M, Bäuerle T, Kuwert T, Schett G, Schmidkonz C. 68Ga-FAPI-04 PET-CT for molecular assessment of fibroblast activation and risk evaluation in systemic sclerosis-associated interstitial lung disease: a single-centre, pilot study. Lancet Rheumatol 2021; 3:e185-e194. [PMID: 38279381 DOI: 10.1016/s2665-9913(20)30421-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/19/2020] [Accepted: 11/26/2020] [Indexed: 01/09/2023]
Abstract
BACKGROUND Interstitial lung disease (ILD) is the most common cause of death in systemic sclerosis. To date, the progression of systemic sclerosis-associated ILD is judged by the accrual of lung damage on CT and pulmonary function tests. However, diagnostic tools to assess disease activity are not available. Here, we tested the hypothesis that quantification of fibroblast activation by PET-CT using a 68Ga-labelled selective inhibitor of prolyl endopeptidase FAP (68Ga-FAPI-04) would correlate with ILD activity and disease progression in patients with systemic sclerosis-associated ILD. METHODS Between Sept 10, 2018, and April 8, 2020, 21 patients with systemic sclerosis-associated ILD confirmed by high-resolution CT (HRCT) within 12 months of inclusion and with onset of systemic sclerosis-associated ILD within 5 years or signs of progressive ILD and 21 controls without ILD were consecutively enrolled. All participants underwent 68Ga-FAPI-04 PET-CT imaging and standard-of-care procedures, including HRCT and pulmonary function tests at baseline. Patients with systemic sclerosis-associated ILD were followed for 6 months with HRCT and pulmonary function tests. We compared baseline 68Ga-FAPI-04 PET-CT uptake with standard diagnostic tools and predictors of ILD progression. The association of 68Ga-FAPI-04 uptake with changes in forced vital capacity was analysed using mixed-effects models. Follow-up 68Ga-FAPI-04 PET-CT scans were obtained in a subset of patients treated with nintedanib (follow-up between 6-10 months) to assess change over time. FINDINGS 68Ga-FAPI-04 accumulated in fibrotic areas of the lungs in patients with systemic sclerosis-associated ILD compared with controls, with a median standardised uptake value (SUV) mean over the whole lung of 0·80 (IQR 0·60-2·10) in the systemic sclerosis-ILD group and 0·50 (0·40-0·50) in the control group (p<0·0001) and a mean whole lung maximal SUV of 4·40 (range 3·05-5·20) in the systemic sclerosis-ILD group compared with 0·70 (0·65-0·70) in the control group (p<0·0001). Whole-lung FAPI metabolic active volume (wlFAPI-MAV) and whole-lung total lesion FAPI (wlTL-FAPI) were not measurable in control participants, because no 68Ga-FAPI-04 uptake above background level was observed. In the systemic sclerosis-ILD group the median wlFAPI-MAV was 254·00 cm3 (IQR 163·40-442·30), and the median wlTL-FAPI was 183·60 cm3 (98·04-960·70). 68Ga-FAPI-04 uptake was higher in patients with extensive disease, with previous ILD progression, or high EUSTAR activity scores than in those with with limited disease, previously stable ILD, or low EUSTAR activity scores. Increased 68Ga-FAPI-04 uptake at baseline was associated with progression of ILD independently of extent of involvement on HRCT scan and the forced vital capacity at baseline. In consecutive 68Ga-FAPI-04 PET-CTs, changes in 68Ga-FAPI-04 uptake was concordant with the observed response to the fibroblast-targeting antifibrotic drug nintedanib. INTERPRETATION Our study presents the first in-human evidence that fibroblast activation correlates with fibrotic activity and disease progression in the lungs of patients with systemic sclerosis-associated ILD and that 68Ga-FAPI-04 PET-CT might improve risk assessment of systemic sclerosis-associated ILD. FUNDING German Research Foundation, Erlangen Anschubs-und Nachwuchsfinanzierung, Interdisziplinäres Zentrum für Klinische Forschung Erlangen, Bundesministerium für Bildung und Forschung, Deutsche Stiftung Systemische Sklerose, Wilhelm-Sander-Foundation, Else-Kröner-Fresenius-Foundation, European Research Council, Ernst-Jung-Foundation, and Clinician Scientist Program Erlangen.
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Affiliation(s)
- Christina Bergmann
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Jörg H W Distler
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany.
| | - Christoph Treutlein
- Department of Radiology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Koray Tascilar
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Anna-Theresa Müller
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Armin Atzinger
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Alexandru-Emil Matei
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Johannes Knitza
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Andrea-Hermina Györfi
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Anja Lück
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Clara Dees
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Alina Soare
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Andreas Ramming
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Verena Schönau
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Oliver Distler
- Rheumaklinik, University Hospital Zurich, Zurich, Switzerland
| | - Olaf Prante
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Philipp Ritt
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Theresa Ida Götz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Markus Köhner
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Michael Cordes
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Tobias Bäuerle
- Department of Radiology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Georg Schett
- Department of Internal Medicine 3-Rheumatology and Immunology, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Christian Schmidkonz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany
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Ott J, Spilhaug MM, Maschauer S, Rafique W, Jakobsson JE, Hartvig K, Hübner H, Gmeiner P, Prante O, Riss PJ. Pharmacological Characterization of Low-to-Moderate Affinity Opioid Receptor Agonists and Brain Imaging with 18F-Labeled Derivatives in Rats. J Med Chem 2020; 63:9484-9499. [PMID: 32787100 PMCID: PMC7497404 DOI: 10.1021/acs.jmedchem.0c00683] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The 3,4-dichloro-N-(1-(dimethylamino)cyclohexyl)methyl benzamide scaffold was studied as a template for 18F-positron emission tomography (18F-PET) radiotracer development emphasizing sensitivity to changes in opioid receptor (OR) occupancy over high affinity. Agonist potency, binding affinity, and relevant pharmacological parameters of 15 candidates were investigated. Two promising compounds 3b and 3e with μ-OR (MOR) selective agonist activity in the moderate range (EC50 = 1-100 nM) were subjected to 18F-fluorination, autoradiography, and small-animal PET imaging. Radioligands [18F]3b and [18F]3e were obtained in activity yields of 21 ± 5 and 23 ± 4% and molar activities of 25-40 and 200-300 GBq/μmol, respectively. Displaceable binding matching MOR distribution in the brain was confirmed by imaging. Radioligands showed a rapid pharmacokinetic profile; however, metabolite-corrected, blood-based modeling was required for data analysis. Observed BPND was low, although treatment with naloxone leads to a marked decrease in specific binding, confirming the discovery of a new template for 18F-labeled OR-agonist PET ligands.
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Affiliation(s)
- Julian Ott
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 12, D-91054 Erlangen, Germany
| | - Mona M Spilhaug
- Realomics SRI, Kjemisk Institutt, Universitetet i Oslo, N-0376 Oslo, Norway
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 12, D-91054 Erlangen, Germany
| | - Waqas Rafique
- Realomics SRI, Kjemisk Institutt, Universitetet i Oslo, N-0376 Oslo, Norway
| | - Jimmy E Jakobsson
- Realomics SRI, Kjemisk Institutt, Universitetet i Oslo, N-0376 Oslo, Norway
| | - Karoline Hartvig
- Realomics SRI, Kjemisk Institutt, Universitetet i Oslo, N-0376 Oslo, Norway
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Straße 10, D-91058 Erlangen, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Straße 10, D-91058 Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 12, D-91054 Erlangen, Germany
| | - Patrick J Riss
- Realomics SRI, Kjemisk Institutt, Universitetet i Oslo, N-0376 Oslo, Norway.,Division of Clinical Neuroscience, Neuroscience Research Unit, OUS-UllevÅl, N-0450 Oslo, Norway
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Schmidkonz C, Rauber S, Atzinger A, Agarwal R, Götz TI, Soare A, Cordes M, Prante O, Bergmann C, Kleyer A, Ritt P, Maschauer S, Hennig P, Toms J, Köhner M, Manger B, Stone JH, Haberkorn U, Baeuerle T, Distler JHW, Agaimy A, Kuwert T, Schett G, Ramming A. Disentangling inflammatory from fibrotic disease activity by fibroblast activation protein imaging. Ann Rheum Dis 2020; 79:1485-1491. [PMID: 32719042 DOI: 10.1136/annrheumdis-2020-217408] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/19/2020] [Accepted: 06/18/2020] [Indexed: 12/24/2022]
Abstract
OBJECTIVES To date, there is no valuable tool to assess fibrotic disease activity in humans in vivo in a non-invasive way. This study aims to uncouple inflammatory from fibrotic disease activity in fibroinflammatory diseases such as IgG4-related disease. METHODS In this cross-sectional clinical study, 27 patients with inflammatory, fibrotic and overlapping manifestations of IgG4-related disease underwent positron emission tomography (PET) scanning with tracers specific for fibroblast activation protein (FAP; 68Ga-FAP inhibitor (FAPI)-04), 18F-fluorodeoxyglucose (FDG), MRI and histopathological assessment. In a longitudinal approach, 18F-FDG and 68Ga-FAPI-04 PET/CT data were evaluated before and after immunosuppressive treatment and correlated to clinical and MRI data. RESULTS Using combination of 68Ga-FAPI-04 and 18F-FDG-PET, we demonstrate that non-invasive functional tracking of IgG4-related disease evolution from inflammatory towards a fibrotic outcome becomes feasible. 18F-FDG-PET positive lesions showed dense lymphoplasmacytic infiltration of IgG4 + cells in histology, while 68Ga-FAPI-04 PET positive lesions showed abundant activated fibroblasts expressing FAP according to results from RNA-sequencing of activated fibroblasts. The responsiveness of fibrotic lesions to anti-inflammatory treatment was far less pronounced than that of inflammatory lesions. CONCLUSION FAP-specific PET/CT permits the discrimination between inflammatory and fibrotic activity in IgG4-related disease. This finding may profoundly change the management of certain forms of immune-mediated disease, such as IgG4-related disease, as subtypes dominated by fibrosis may require different approaches to control disease progression, for example, specific antifibrotic agents rather than broad spectrum anti-inflammatory treatments such as glucocorticoids.
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Affiliation(s)
- Christian Schmidkonz
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Simon Rauber
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Armin Atzinger
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Rahul Agarwal
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Theresa Ida Götz
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Alina Soare
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Michael Cordes
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Christina Bergmann
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Arnd Kleyer
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Philipp Ritt
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Peter Hennig
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Johannes Toms
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Markus Köhner
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Bernhard Manger
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - John H Stone
- Massachusetts General Hospital Rheumatology Unit, Harvard Medical School, Boston, Massachusetts, USA
| | - Uwe Haberkorn
- Department of Nuclear Medicine, Heidelberg University, Heidelberg, Baden-Württemberg, Germany
| | - Tobias Baeuerle
- Institute of Radiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Bayern, Germany
| | - Jörg H W Distler
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Abbas Agaimy
- Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Bayern, Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Georg Schett
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
| | - Andreas Ramming
- Department of Internal Medicine 3, Rheumatology & Immunology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg and University Hospital Erlangen, Erlangen, Germany
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Willmann M, Ermert J, Prante O, Hübner H, Gmeiner P, Neumaier B. Radiosynthesis and evaluation of 18F-labeled dopamine D 4-receptor ligands. Nucl Med Biol 2020; 92:43-52. [PMID: 32718750 DOI: 10.1016/j.nucmedbio.2020.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 07/09/2020] [Indexed: 11/24/2022]
Abstract
INTRODUCTION The dopamine D4 receptor (D4R) has attracted considerable attention as potential target for the treatment of a broad range of central nervous system disorders. Although many efforts have been made to improve the performance of putative radioligand candidates, there is still a lack of D4R selective tracers suitable for in vivo PET imaging. Thus, the objective of this work was to develop a D4-selective PET ligand for clinical applications. METHODS Four compounds based on previous and new lead structures were prepared and characterized with regard to their D4R subtype selectivity and predicted lipophilicity. From these, 3-((4-(2-fluorophenyl)piperazin-1-yl)methyl)-1H-pyrrolo[2,3-b]pyridine I and (S)-4-(3-fluoro-4-methoxybenzyl)-2-(phenoxymethyl)morpholine II were selected for labeling with fluorine-18 and subsequent evaluation by in vitro autoradiography to assess their suitability as D4 radioligand candidates for in vivo imaging. RESULTS The radiosynthesis of [18F]I and [18F]II was successfully achieved by copper-mediated radiofluorination with radiochemical yields of 7% and 66%, respectively. The radioligand [18F]II showed specific binding in areas where D4 expression is expected, whereas [18F]I did not show any uptake in distinct brain regions and exhibited an unacceptable degree of non-specific binding. CONCLUSIONS The compounds studied exhibited high D4R subtype selectivity and logP values compatible with high brain uptake, but only ligand [18F]II showed low non-specific binding and is therefore a good candidate for further evaluation. ADVANCES IN KNOWLEDGE The discovery of new lead structures for high-affinity D4 ligands opens up new possibilities for the development of suitable PET-radioligands. IMPLICATIONS FOR PATIENT PET-imaging of dopamine D4-receptors could facilitate understanding, diagnosis and treatment of neuropsychiatric and neurodegenerative diseases.
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Affiliation(s)
- Michael Willmann
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen Straße, 52428 Jülich, Germany
| | - Johannes Ermert
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen Straße, 52428 Jülich, Germany.
| | - Olaf Prante
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, 91054 Erlangen, Germany
| | - Harald Hübner
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department Chemistry and Pharmacy, Medicinal Chemistry, 91058 Erlangen, Germany
| | - Peter Gmeiner
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department Chemistry and Pharmacy, Medicinal Chemistry, 91058 Erlangen, Germany
| | - Bernd Neumaier
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen Straße, 52428 Jülich, Germany; University of Colgne, Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, 50937 Cologne, Germany
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Götz TI, Lang EW, Prante O, Cordes M, Kuwert T, Ritt P, Ludwig B, Schmidkonz C. Estimation of [177Lu]PSMA-617 tumor uptake based on voxel-wise 3D Monte Carlo tumor dosimetry in patients with metastasized castration resistant prostate cancer. Nuklearmedizin 2020; 59:365-374. [PMID: 32663888 DOI: 10.1055/a-1204-9932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVE Patients with advanced prostate cancer are suitable candidates for [177Lu]PSMA-617 therapy. Integrated SPECT/CT systems have the potential to improve the accuracy of patient-specific tumor dosimetry. We present a novel patient-specific Monte Carlo based voxel-wise dosimetry approach to determine organ and total tumor doses (TTD). METHODS 13 patients with histologically confirmed metastasized castration-resistant prostate cancer were treated with a total of 18 cycles of [177Lu]PSMA-617 therapy. In each patient, dosimetry was performed after the first cycle of [177Lu]PSMA-617 therapy. Regions of interest were defined manually on the SPECT/CT images for the kidneys, spleen and all 295 PSMA-positive tumor lesions in the field of view. The absorbed dose to normal organs and to all tumor lesions were calculated by a three dimensional dosimetry method based on Monte Carlo Simulations. RESULTS The average dose values yielded the following results: 2.59 ± 0.63 Gy (1.67-3.92 Gy) for the kidneys, 0.79 ± 0.46 Gy (0.31-1.90 Gy) for the spleen and 11.00 ± 11.97 Gy (1.28-49.10 Gy) for all tracer-positive tumor lesions. A trend towards higher TTD was observed in patients with Gleason Scores > 8 compared to Gleason Scores ≤ 8 and in lymph node metastases compared to bone metastases. A significant correlation was determined between the serum-PSA level before RLT and the TTD (r = -0.57, p < 0.05), as well as between the TTD with the percentage change of serum-PSA levels before and after therapy was observed (r = -0.57, p < 0.05). Patients with higher total tumor volumes of PSMA-positive lesions demonstrated significantly lower kidney average dose values (r = -0.58, p < 0.05). CONCLUSION The presented novel Monte Carlo based voxel-wise dosimetry calculates a patient specific whole-body dose distribution, thus taking into account individual anatomies and tissue compositions showing promising results for the estimation of radiation doses of normal organs and PSMA-positive tumor lesions.
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Affiliation(s)
- Theresa Ida Götz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Information Sciences, University of Regensburg, Regensburg, Germany.,Biophysics, University of Regensburg, Regensburg, Germany
| | | | - Olaf Prante
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Michael Cordes
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Philipp Ritt
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Bernd Ludwig
- Information Sciences, University of Regensburg, Regensburg, Germany
| | - Christian Schmidkonz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
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20
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Krüll J, Fehler SK, Hofmann L, Nebel N, Maschauer S, Prante O, Gmeiner P, Lanig H, Hübner H, Heinrich MR. Synthesis, Radiosynthesis and Biological Evaluation of Buprenorphine-Derived Phenylazocarboxamides as Novel μ-Opioid Receptor Ligands. ChemMedChem 2020; 15:1175-1186. [PMID: 32378310 PMCID: PMC7383964 DOI: 10.1002/cmdc.202000180] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Indexed: 12/12/2022]
Abstract
Targeted structural modifications have led to a novel type of buprenorphine-derived opioid receptor ligand displaying an improved selectivity profile for the μ-OR subtype. On this basis, it is shown that phenylazocarboxamides may serve as useful bioisosteric replacements for the widely occurring cinnamide units, without loss of OR binding affinity or subtype selectivity. This study further includes functional experiments pointing to weak partial agonist properties of the novel μ-OR ligands, as well as docking and metabolism experiments. Finally, the unique bifunctional character of phenylazocarboxylates, herein serving as precursors for the azocarboxamide subunit, was exploited to demonstrate the accessibility of an 18 F-fluorinated analogue.
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Affiliation(s)
- Jasmin Krüll
- Department of Chemistry and PharmacyPharmaceutical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Stefanie K. Fehler
- Department of Chemistry and PharmacyPharmaceutical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Laura Hofmann
- Department of Chemistry and PharmacyPharmaceutical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Natascha Nebel
- Department of Nuclear MedicineMolecular Imaging and RadiochemistryFriedrich-Alexander-Universität Erlangen-NürnbergSchwabachanlage 1291054ErlangenGermany
| | - Simone Maschauer
- Department of Nuclear MedicineMolecular Imaging and RadiochemistryFriedrich-Alexander-Universität Erlangen-NürnbergSchwabachanlage 1291054ErlangenGermany
| | - Olaf Prante
- Department of Nuclear MedicineMolecular Imaging and RadiochemistryFriedrich-Alexander-Universität Erlangen-NürnbergSchwabachanlage 1291054ErlangenGermany
| | - Peter Gmeiner
- Department of Chemistry and PharmacyPharmaceutical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Harald Lanig
- Central Institute for Scientific Computing (ZISC)Friedrich-Alexander-Universität Erlangen-NürnbergMartensstr. 5a91058ErlangenGermany
| | - Harald Hübner
- Department of Chemistry and PharmacyPharmaceutical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Markus R. Heinrich
- Department of Chemistry and PharmacyPharmaceutical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
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21
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Toms J, Kogler J, Maschauer S, Daniel C, Schmidkonz C, Kuwert T, Prante O. Targeting Fibroblast Activation Protein: Radiosynthesis and Preclinical Evaluation of an 18F-Labeled FAP Inhibitor. J Nucl Med 2020; 61:1806-1813. [PMID: 32332144 DOI: 10.2967/jnumed.120.242958] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 04/05/2020] [Indexed: 12/30/2022] Open
Abstract
Fibroblast activation protein (FAP) has emerged as an interesting molecular target used in the imaging and therapy of various types of cancers. 68Ga-labeled chelator-linked FAP inhibitors (FAPIs) have been successfully applied to PET imaging of various tumor types. To broaden the spectrum of applicable PET tracers for extended imaging studies of FAP-dependent diseases, we herein report the radiosynthesis and preclinical evaluation of an 18F-labeled glycosylated FAPI ([18F]FGlc-FAPI). Methods: An alkyne-bearing precursor was synthesized and subjected to click chemistry-based radiosynthesis of [18F]FGlc-FAPI by 2-step 18F-fluoroglycosylation. FAP-expressing HT1080hFAP cells were used to study competitive binding to FAP, cellular uptake, internalization, and efflux of [18F]FGlc-FAPI in vitro. Biodistribution studies and in vivo small-animal PET studies of [18F]FGlc-FAPI compared with [68Ga]Ga-FAPI-04 were conducted in nude mice bearing HT1080hFAP tumors or U87MG xenografts. Results: [18F]FGlc-FAPI was synthesized with a 15% radioactivity yield and a high radiochemical purity of more than 99%. In HT1080hFAP cells, [18F]FGlc-FAPI showed specific uptake, a high internalized fraction, and low cellular efflux. Compared with FAPI-04 (half maximal inhibitory concentration [IC50] = 32 nM), the glycoconjugate, FGlc-FAPI (IC50 = 167 nM), showed slightly lower affinity for FAP in vitro, whereas plasma protein binding was higher for [18F]FGlc-FAPI. Biodistribution studies revealed significant hepatobiliary excretion of [18F]FGlc-FAPI; however, small-animal PET studies in HT1080hFAP xenografts showed higher specific tumor uptake of [18F]FGlc-FAPI (4.5 percentage injected dose per gram of tissue [%ID/g]) than of [68Ga]Ga-FAPI-04 (2 %ID/g). In U87MG tumor-bearing mice, both tracers showed similar tumor uptake, but [18F]FGlc-FAPI showed a higher tumor retention. Interestingly, [18F]FGlc-FAPI demonstrated high specific uptake in bone structures and joints. Conclusion: [18F]FGlc-FAPI is an interesting candidate for translation to the clinic, taking advantage of the longer half-life and physical imaging properties of 18F. The availability of [18F]FGlc-FAPI may allow extended PET studies of FAP-related diseases, such as cancer, but also arthritis, heart diseases, or pulmonary fibrosis.
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Affiliation(s)
- Johannes Toms
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, Erlangen, Germany
| | - Jürgen Kogler
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, Erlangen, Germany
| | - Simone Maschauer
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, Erlangen, Germany
| | - Christoph Daniel
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nephropathology, Erlangen, Germany; and
| | - Christian Schmidkonz
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Erlangen, Germany
| | - Torsten Kuwert
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Erlangen, Germany
| | - Olaf Prante
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Translational Research Center, Erlangen, Germany .,Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Nuclear Medicine, Erlangen, Germany
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22
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Goetz TI, Lang EW, Prante O, Maier A, Cordes M, Kuwert T, Ritt P, Schmidkonz C. Three-dimensional Monte Carlo-based voxel-wise tumor dosimetry in patients with neuroendocrine tumors who underwent 177Lu-DOTATOC therapy. Ann Nucl Med 2020; 34:244-253. [PMID: 32114682 PMCID: PMC7101301 DOI: 10.1007/s12149-020-01440-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 01/20/2020] [Indexed: 01/09/2023]
Abstract
Background Patients with advanced neuroendocrine tumors (NETs) of the midgut are suitable candidates for 177Lu-DOTATOC therapy. Integrated SPECT/CT systems have the potential to help improve the accuracy of patient-specific tumor dosimetry. Dose estimations to target organs are generally performed using the Medical Internal Radiation Dose scheme. We present a novel Monte Carlo-based voxel-wise dosimetry approach to determine organ- and tumor-specific total tumor doses (TTD). Methods A cohort of 14 patients with histologically confirmed metastasized NETs of the midgut (11 men, 3 women, 62.3 ± 11.0 years of age) underwent a total of 39 cycles of 177Lu-DOTATOC therapy (mean 2.8 cycles, SD ± 1 cycle). After the first cycle of therapy, regions of interest were defined manually on the SPECT/CT images for the kidneys, the spleen, and all 198 tracer-positive tumor lesions in the field of view. Four SPECT images, taken at 4 h, 24 h, 48 h and 72 h after injection of the radiopharmaceutical, were used to determine their effective half-lives in the structures of interest. The absorbed doses were calculated by a three-dimensional dosimetry method based on Monte Carlo simulations. TTD was calculated as the sum of all products of single tumor doses with single tumor volumes divided by the sum of all tumor volumes. Results The average dose values per cycle were 3.41 ± 1.28 Gy (1.91–6.22 Gy) for the kidneys, 4.40 ± 2.90 Gy (1.14–11.22 Gy) for the spleen, and 9.70 ± 8.96 Gy (1.47–39.49 Gy) for all 177Lu-DOTATOC-positive tumor lesions. Low- and intermediate-grade tumors (G 1–2) absorbed a higher TTD compared to high-grade tumors (G 3) (signed-rank test, p = < 0.05). The pre-therapeutic chromogranin A (CgA) value and the TTD correlated significantly (Pearson correlation: = 0.67, p = 0.01). Higher TTD resulted in a significant decrease of CgA after therapy. Conclusion These results suggest that Monte Carlo-based voxel-wise dosimetry is a very promising tool for predicting the absorbed TTD based on histological and clinical parameters.
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Affiliation(s)
- Th I Goetz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Pattern Recognition Lab, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Biophysics, University of Regensburg, Regensburg, Germany
| | - E W Lang
- Biophysics, University of Regensburg, Regensburg, Germany
| | - O Prante
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - A Maier
- Pattern Recognition Lab, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - M Cordes
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - T Kuwert
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - P Ritt
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Christian Schmidkonz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany. .,Clinic of Nuclear Medicine, University of Erlangen-Nuremberg, Ulmenweg 18, 91054, Erlangen, Germany.
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23
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Potemkin R, Strauch B, Kuwert T, Prante O, Maschauer S. Development of 18F-Fluoroglycosylated PSMA-Ligands with Improved Renal Clearance Behavior. Mol Pharm 2020; 17:933-943. [DOI: 10.1021/acs.molpharmaceut.9b01179] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Roman Potemkin
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
| | - Brigitte Strauch
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander University (FAU), Schwabachanlage 12, 91054 Erlangen, Germany
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24
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Schmidkonz C, Krumbholz M, Atzinger A, Cordes M, Goetz TI, Prante O, Ritt P, Schaefer C, Agaimy A, Hartmann W, Rössig C, Fröhlich B, Bäuerle T, Dirksen U, Kuwert T, Metzler M. Assessment of treatment responses in children and adolescents with Ewing sarcoma with metabolic tumor parameters derived from 18F-FDG-PET/CT and circulating tumor DNA. Eur J Nucl Med Mol Imaging 2019; 47:1564-1575. [PMID: 31853559 DOI: 10.1007/s00259-019-04649-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 12/05/2019] [Indexed: 11/25/2022]
Abstract
PURPOSE The purpose of this study was to perform a prospective integrated analysis of 18F-fluorodeoxyglucose (18F-FDG)-positron emission tomography (PET)/computed tomography (CT) and circulating tumor DNA (ctDNA) to assess responses to multimodal chemotherapy in children and adolescents suffering from Ewing sarcoma (EwS). METHODS A total of 20 patients with histologically confirmed EwS underwent multiple 18F-FDG-PET/CT, performed at the time of each patient's initial diagnosis and after the second and fifth induction chemotherapy block (EWING2008 treatment protocol, NCT00987636). Additional PET examinations were performed as clinically indicated in some patients, e.g., in patients suspected of having progressive or relapsing disease. All 263 18F-FDG-positive lesions in the field of view suggestive of tumor tissue were assessed quantitatively to calculate PET-derived parameters, including whole-body metabolic tumor volume (wb-MTV) and whole-body total lesion glycolysis (wb-TLG), as well as the following data: standardized uptake value (SUV)max and SUVmean. Tumor-specific ctDNA in patient plasma samples was quantified using digital droplet PCR (ddPCR), and the correlations between ctDNA levels and PET-derived parameters were analyzed. Metabolic responses to multimodal chemotherapy as assessed with PET-parameters were compared to biochemical responses as assessed with changes in ctDNA levels. RESULTS Twenty patients underwent a total of 87 18F-FDG-PET/CT scans, which detected 263 FDG-positive tumor lesions. Significant correlations between SUVmax, SUVmean, wb-MTV and wb-TLG values, and ctDNA levels were observed (all p < 0.0001). All patients suffering from EwS, with histology serving as gold standard, also presented with a positive corresponding ctDNA sample and a positive 18F-FDG-PET/CT examination before initiation of therapy. There were no false-negative results. Evaluation of treatment response after the fifth block of induction chemotherapy showed that the agreement between the metabolic response and biochemical response was 90%, which was statistically significant (Cohen κ = 0.62; p < 0.05). Non-detectable ctDNA after the second block of induction chemotherapy was associated with complete biochemical and metabolic responses after the fifth block of induction chemotherapy in 16/17 patients (94%). During a median follow-up period of 36 months (range: 8-104 months), four patients had tumor relapses, which, in all cases, were accompanied by an increase in plasma ctDNA levels and a positive 18F-FDG-PET/CT. No false-negative results were observed in the study cohort. Complete biochemical and metabolic responses after the fifth block of induction chemotherapy had a high positive predictive value for disease remission during the follow-up period; specifically, the positive predictive value was 88%. CONCLUSION The combination of 18F-FDG-PET/CT and ctDNA quantification is a very promising noninvasive tool for assessing treatment responses and detecting tumor relapses in children and young adolescents suffering from EwS who are undergoing multimodal chemotherapy.
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Affiliation(s)
- Christian Schmidkonz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - Manuela Krumbholz
- Department of Pediatrics and Adolescent Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Armin Atzinger
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Michael Cordes
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Theresa Ida Goetz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Philipp Ritt
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Christiane Schaefer
- Pediatrics III, West German Cancer Centre, University Hospital of Essen, Essen, Germany
| | - Abbas Agaimy
- Institute of Pathology, University Hospital, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Wolfgang Hartmann
- Division of Translational Pathology, Gerhard-Domagk Institute of Pathology, University Hospital of Münster, Münster, Germany
| | - Claudia Rössig
- Department of Pediatric Hematology and Oncology, University Children's Hospital Münster, Münster, Germany
| | - Birgit Fröhlich
- Department of Pediatric Hematology and Oncology, University Children's Hospital Münster, Münster, Germany
| | - Tobias Bäuerle
- Institute of Radiology Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Uta Dirksen
- Pediatrics III, West German Cancer Centre, University Hospital of Essen, Essen, Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Markus Metzler
- Department of Pediatrics and Adolescent Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
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Schmidkonz C, Goetz TI, Kuwert T, Ritt P, Prante O, Bäuerle T, Goebell P, Cordes M. PSMA SPECT/CT with 99mTc-MIP-1404 in biochemical recurrence of prostate cancer: predictive factors and efficacy for the detection of PSMA-positive lesions at low and very-low PSA levels. Ann Nucl Med 2019; 33:891-898. [PMID: 31502084 DOI: 10.1007/s12149-019-01400-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 09/01/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND The in vivo expression of the prostate-specific membrane antigen (PSMA) can be investigated using the SPECT-suitable tracer 99mTc-MIP-1404. We investigated the performance of 99mTc-MIP-1404 PSMA SPECT/CT in the detection of PSMA-positive tumor lesions in patients suffering from biochemical recurrence of prostate cancer presenting with serum levels of the prostate-specific antigen (PSA) below 1 ng/mL. METHODS We retrospectively analyzed 99mTc-MIP-1404-SPECT/CT scans of 50 patients (25 with low PSA levels between > 0.5 and 1 ng/mL and 25 with very low PSA levels between 0.2 and 0.5 ng/mL) that had undergone whole-body planar scintigraphy and SPECT/CT of the thorax, abdomen and pelvis 3-4 h p.i. of 691 ± 72 MBq 99mTc-MIP-1404. All datasets were evaluated for the presence and location of PSMA-positive tumor lesions, in which maximal standardized uptake values (SUVmax) were also measured. Based on the results of the quantitative evaluation as well as on biochemical and histological parameters, predictive factors for a positive 99mTc-MIP-1404 scan result were determined. The influence of 99mTc-MIP-1404 PSMA SPECT/CT on further therapy planning was assessed, based on the decision-making of the interdisciplinary tumor board. RESULTS Pathological 99mTc-MIP-1404 uptake was detected in a total of 25 patients (50%). In the very low PSA subgroup, detection rates of PSMA-positive lesions suggestive of tumor recurrence were 44%, in the low-PSA subgroup 56%. Gleason scores ≥ 8 and the presence of antiandrogen deprivation therapy were further significant predictors of pathological 99mTc-MIP-1404 uptake. This was paralleled by significantly higher lesional SUVmax patients with PSA levels > 0.5 ng/mL and Gleason scores ≥ 8 compared to those without these two features. Changes in therapeutic strategy following MIP-1404 imaging were recommended by the interdisciplinary tumor board in 25/50 of patients. CONCLUSION 99mTc-MIP-1404 PSMA-SPECT/CT demonstrated a high performance in detecting PSMA-positive lesions suggestive of tumor recurrence in patients with biochemical recurrence of prostate cancer and low and very low serum PSA levels. Results from MIP-1404 PSMA SPECT/CT have therapeutic impact in one-half of the patients examined by this technology.
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Affiliation(s)
- Christian Schmidkonz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Ulmenweg 18, 91054, Erlangen, Germany.
| | - Theresa Ida Goetz
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Ulmenweg 18, 91054, Erlangen, Germany.,Pattern Recognition Lab, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Ulmenweg 18, 91054, Erlangen, Germany
| | - Philipp Ritt
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Ulmenweg 18, 91054, Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Ulmenweg 18, 91054, Erlangen, Germany
| | - Tobias Bäuerle
- Institute of Radiology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Peter Goebell
- Department of Urology and Pediatric Urology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Michael Cordes
- Department of Nuclear Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Ulmenweg 18, 91054, Erlangen, Germany
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26
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Daum S, Toms J, Reshetnikov V, Özkan HG, Hampel F, Maschauer S, Hakimioun A, Beierlein F, Sellner L, Schmitt M, Prante O, Mokhir A. Identification of Boronic Acid Derivatives as an Active Form of N-Alkylaminoferrocene-Based Anticancer Prodrugs and Their Radiolabeling with 18F. Bioconjug Chem 2019; 30:1077-1086. [PMID: 30768258 DOI: 10.1021/acs.bioconjchem.9b00019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
N-Alkylaminoferrocene (NAAF)-based prodrugs are activated in the presence of elevated amounts of reactive oxygen species (ROS), which corresponds to cancer specific conditions, with formation of NAAF and p-quinone methide. Both products act synergistically by increasing oxidative stress in cancer cells that causes their death. Though it has already been demonstrated that the best prodrugs of this type retain their antitumor activity in vivo, the effects were found to be substantially weaker than those observed in cell cultures. Moreover, the mechanistic studies of these compounds in vivo are missing. For clarification of these important questions, labeling of the prodrugs with radioactive moieties would be necessary. In this paper, we first observed that the representative NAAF-based prodrugs are hydrolyzed in dilute aqueous solutions to the corresponding arylboronic acids. We confirmed that these products are responsible for ROS amplification and anticancer properties of the parent prodrugs. Next, we developed the efficient synthetic protocol for radiolabeling the hydrolyzed NAAF-based prodrugs by [18F]fluoroglucosylation under the conditions of the copper(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition and used this protocol to prepare one representative hydrolyzed NAAF-based prodrug radiolabeled with 18F. Finally, we studied the stability of the 18F-labeled compound in human serum in vitro and in rat blood in vivo and obtained preliminary data on its biodistribution in vivo in mice carrying pancreatic (AR42J) and prostate (PC3) tumors by applying PET imaging studies. The compound described in this paper will help to understand in vivo effects (e.g., pharmacokinetics, accumulation in organs, the nature of side effects) of these prodrugs that will strongly contribute to their advancement to clinical trials.
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Affiliation(s)
- Steffen Daum
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Chemistry and Pharmacy, Organic Chemistry Chair II , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Johannes Toms
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Nuclear Medicine, Molecular Imaging and Radiochemistry , Schwabachanlage 6 , 91054 Erlangen , Germany
| | - Viktor Reshetnikov
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Chemistry and Pharmacy, Organic Chemistry Chair II , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Hülya Gizem Özkan
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Chemistry and Pharmacy, Organic Chemistry Chair II , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Frank Hampel
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Chemistry and Pharmacy, Organic Chemistry Chair II , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Simone Maschauer
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Nuclear Medicine, Molecular Imaging and Radiochemistry , Schwabachanlage 6 , 91054 Erlangen , Germany
| | - Amir Hakimioun
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Chemistry and Pharmacy, Computer-Chemistry-Center and Interdisciplinary Center for Molecular Materials , Nägelsbachstr. 25 , 91052 Erlangen , Germany
| | - Frank Beierlein
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Chemistry and Pharmacy, Computer-Chemistry-Center and Interdisciplinary Center for Molecular Materials , Nägelsbachstr. 25 , 91052 Erlangen , Germany
| | - Leopold Sellner
- University Hospital Heidelberg , Department of Medicine V , 69120 Heidelberg , Germany
| | - Michael Schmitt
- University Hospital Heidelberg , Department of Medicine V , 69120 Heidelberg , Germany
| | - Olaf Prante
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Nuclear Medicine, Molecular Imaging and Radiochemistry , Schwabachanlage 6 , 91054 Erlangen , Germany
| | - Andriy Mokhir
- Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Department of Chemistry and Pharmacy, Organic Chemistry Chair II , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
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Ellmann S, Seyler L, Evers J, Heinen H, Bozec A, Prante O, Kuwert T, Uder M, Bäuerle T. Prediction of early metastatic disease in experimental breast cancer bone metastasis by combining PET/CT and MRI parameters to a Model-Averaged Neural Network. Bone 2019; 120:254-261. [PMID: 30445200 DOI: 10.1016/j.bone.2018.11.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 11/07/2018] [Accepted: 11/12/2018] [Indexed: 01/06/2023]
Abstract
Macrometastases in bone are preceded by bone marrow invasion of disseminated tumor cells. This study combined functional imaging parameters from FDG-PET/CT and MRI in a rat model of breast cancer bone metastases to a Model-averaged Neural Network (avNNet) for the detection of early metastatic disease and prediction of future macrometastases. Metastases were induced in 28 rats by injecting MDA-MB-231 breast cancer cells into the right superficial epigastric artery, resulting in the growth of osseous metastases in the right hind leg of the animals. All animals received FDG-PET/CT and MRI at days 0, 10, 20 and 30 after tumor cell injection. In total, 18/28 rats presented with metastases at days 20 or 30 (64.3%). None of the animals featured morphologic bone lesions during imaging at day 10, and the imaging parameters acquired at day 10 did not differ significantly between animals with metastases at or after day 20 and those without (all p > 0.3). The avNNet trained with the imaging parameters acquired at day 10, however, achieved an accuracy of 85.7% (95% CI 67.3-96.0%) in predicting future macrometastatic disease (ROCAUC 0.90; 95% CI 0.76-1.00), and significantly outperformed the predictive capacities of all single parameters (all p ≤ 0.02). The integration of functional FDG-PET/CT and MRI parameters into an avNNet can thus be used to predict macrometastatic disease with high accuracy, and their combination might serve as a surrogate marker for bone marrow invasion as an early metastatic process that is commonly missed during conventional staging examinations.
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Affiliation(s)
- Stephan Ellmann
- Department of Radiology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
| | - Lisa Seyler
- Department of Radiology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
| | - Jochen Evers
- Department of Radiology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany
| | - Henrik Heinen
- Department of Radiology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany
| | - Aline Bozec
- Department of Internal Medicine 3, Rheumatology and Immunology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
| | - Olaf Prante
- Department of Nuclear Medicine, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
| | - Torsten Kuwert
- Department of Nuclear Medicine, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
| | - Michael Uder
- Department of Radiology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
| | - Tobias Bäuerle
- Department of Radiology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
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28
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Toms J, Reshetnikov V, Maschauer S, Mokhir A, Prante O. Radiosynthesis of an 18
F-fluoroglycosylated aminoferrocene for in-vivo imaging of reactive oxygen species activity by PET. J Labelled Comp Radiopharm 2018; 61:1081-1088. [DOI: 10.1002/jlcr.3687] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/14/2018] [Accepted: 10/01/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Johannes Toms
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich-Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Viktor Reshetnikov
- Department of Chemistry and Pharmacy, Organic Chemistry Chair II; Friedrich-Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich-Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Andriy Mokhir
- Department of Chemistry and Pharmacy, Organic Chemistry Chair II; Friedrich-Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich-Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
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Abstract
Summary
Aim: Disturbances of the D4 receptor subtype have been implicated in the genesis of a broad range of psychiatric disorders. In order to assess the suitability of a radioiodinated analogue of the D4-selective ligand FAUC 113 for tracer studies in vivo, we investigated the in-vivo stability, biodistribution and brain-uptake of 7-131I-FAUC 113 in Sprague-Dawley rats. Methods: Radiolabelling was carried out with high radiochemical yield and specific activity. After intravenous injection, blood and tissue samples, taken at designated time intervals, were collected for analysis. Analyses of metabolites were performed by radiohplc and radio-tlc. For in-vivo evaluation, sagittal cryo-sections of the rat brain were investigated by in-vitro and exvivo autoradiography on a μ-Imager system. Results: 7-131I-FAUC 113 was rapidly cleared from blood. Highest uptake was observed in kidney (0.603±0.047% ID/g, n=4) and liver (0.357±0.070% ID/g, n=4) at 10 min p.i.; 7-131I-FAUC 113 displayed rapid uptake (0.21-0.26% ID/g) and fast clearance in various brain regions consistent with the determined logP-value of 2.36±0.15 (n=4). In-vivo stability of 7-131I-FAUC 113 was confirmed in the frontal cortex (>95%). Ex-vivo autoradiography revealed a frontal cortex-to-cerebellum ratio of 1.57±0.13 at 10 min p.i. (n=6). Coinjection with L-750667 could not suppress any putative specific binding of 7-131I-FAUC 113. In-vitro autoradiography using authentic 7-iodo-FAUC 113 or L-750667 failed to cause significant displacement of the radioligand. Conclusions: Radioiodinated FAUC 113 does not allow imaging of D4 receptors in the rat brain in vivo nor in vitro. Further work should aim at the development of selective dopamine D4 radioligands with improved tracer characteristics, such as receptor affinity and subtype selectivity, specific activity or blood-brainbarrier permeability.
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30
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Maschauer S, Prante O. Radiopharmaceuticals for imaging and endoradiotherapy of neurotensin receptor-positive tumors. J Labelled Comp Radiopharm 2018; 61:309-325. [DOI: 10.1002/jlcr.3581] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 10/13/2017] [Accepted: 10/24/2017] [Indexed: 12/11/2022]
Affiliation(s)
- Simone Maschauer
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine; Friedrich Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Olaf Prante
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine; Friedrich Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
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31
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Schmidkonz C, Hollweg C, Beck M, Reinfelder J, Goetz TI, Sanders JC, Schmidt D, Prante O, Bäuerle T, Cavallaro A, Uder M, Wullich B, Goebell P, Kuwert T, Ritt P. 99m Tc-MIP-1404-SPECT/CT for the detection of PSMA-positive lesions in 225 patients with biochemical recurrence of prostate cancer. Prostate 2018; 78:54-63. [PMID: 29105797 DOI: 10.1002/pros.23444] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Accepted: 10/10/2017] [Indexed: 11/10/2022]
Abstract
BACKGROUND 99m Tc-MIP-1404 (Progenics Pharmaceuticals, Inc., New York, NY) is a novel, SPECT-compatible 99m Tc-labeled PSMA inhibitor for the detection of prostate cancer. We present results of its clinical use in a cohort of 225 men with histologically confirmed prostate cancer referred for workup of biochemical relapse. METHODS From April 2013 to April 2017, 99m Tc-MIP1404-scintigraphy was performed in 225 patients for workup of PSA biochemical relapse of prostate cancer. Whole-body planar and SPECT/CT images of the lower abdomen and thorax were obtained 3-4 h p.i. of 710 ± 64 MBq 99m Tc-MIP-1404. Images were visually analyzed for presence and location of abnormal uptake. In addition, quantitative analysis of the SPECT/CT data was carried out on a subset of 125 patients. Follow-up reports of subsequent therapeutic interventions were available for 59% (139) of all patients. RESULTS Tracer-positive lesions were detected in 77% (174/225) of all patients. Detections occurred at the area of local recurrence in the prostate in 25% of patients (or a total of 56), with metastases in lymph nodes in 47% (105), bone in 27% (60), lung in 5% (12), and other locations in 2% (4) of patients. Detection rates were 90% at PSA levels ≥2 ng/mL and 54% below that threshold. Lesional SUVmax values were, on average, 32.2 ± 29.6 (0.8-142.2), and tumor-to-normal ratios 146.6 ± 160.5 (1.9-1482.4). The PSA level correlated significantly with total uptake of MIP-1404 in tumors (P < 0.001). Furthermore, total tumor uptake was significantly higher in patients with Gleason scores ≥8 compared to those with Gleason scores ≤7 (P < 0.05). In patients with androgen deprivation therapy, the detection rate was significantly higher compared to patients without androgen deprivation therapy (86% vs 71%, P < 0.001). Based on 99m Tc-MIP-1404-imaging and other information, an interdisciplinary tumor board review recommended changes to treatment plans in 74% (104/139) of those patients for whom the necessary documentation was available. CONCLUSION SPECT/CT with 99m Tc-labeled MIP-1404 has a high probability in detecting PSMA-positive lesions in patients with elevated PSA. Statistical analysis disclosed significant relationship between quantitative 99m Tc-MIP-1404 uptake, PSA level, and Gleason score.
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Affiliation(s)
| | - Claudia Hollweg
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
| | - Michael Beck
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
| | - Julia Reinfelder
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
| | - Theresa I Goetz
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
- Pattern Recognition Lab, University Erlangen-Nürnberg, Erlangen, Germany
| | - James C Sanders
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
- Pattern Recognition Lab, University Erlangen-Nürnberg, Erlangen, Germany
| | - Daniela Schmidt
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
| | - Olaf Prante
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
| | - Tobias Bäuerle
- Institute of Radiology, University Hospital Erlangen, Erlangen, Germany
| | | | - Michael Uder
- Institute of Radiology, University Hospital Erlangen, Erlangen, Germany
| | - Bernd Wullich
- Department of Urology, Pediatric Urology, University Hospital Erlangen, Erlangen, Germany
| | - Peter Goebell
- Department of Urology, Pediatric Urology, University Hospital Erlangen, Erlangen, Germany
| | - Torsten Kuwert
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
| | - Philipp Ritt
- Clinic of Nuclear Medicine, University Hospital Erlangen, Erlangen, Germany
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32
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Nebel N, Strauch B, Maschauer S, Lasch R, Rampp H, Fehler SK, Bock LR, Hübner H, Gmeiner P, Heinrich MR, Prante O. [ 18F]Fluorophenylazocarboxylates: Design and Synthesis of Potential Radioligands for Dopamine D3 and μ-Opioid Receptor. ACS Omega 2017; 2:8649-8659. [PMID: 29479577 PMCID: PMC5819854 DOI: 10.1021/acsomega.7b01374] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/16/2017] [Indexed: 06/08/2023]
Abstract
18F-Labeled building blocks from the type of [18F]fluorophenylazocarboxylic-tert-butyl esters offer a rapid, mild, and reliable method for the 18F-fluoroarylation of biomolecules. Two series of azocarboxamides were synthesized as potential radioligands for dopamine D3 and the μ-opioid receptor, revealing compounds 3d and 3e with single-digit and sub-nanomolar affinity for the D3 receptor and compound 4c with only micromolar affinity for the μ-opioid receptor, but enhanced selectivity for the μ-subtype in comparison to the lead compound AH-7921. A "minimalist procedure" without the use of a cryptand and base for the preparation of 4-[18F]fluorophenylazocarboxylic-tert-butyl ester [18F]2a was established, together with the radiosynthesis of methyl-, methoxy-, and phenyl-substituted derivatives ([18F]2b-f). With the substituted [18F]fluorophenylazocarbylates in hand, two prototype azocarboxylates radioligands were synthesized by 18F-fluoroarylation, namely the methoxy azocarboxamide [18F]3d as the D3 receptor radioligand and [18F]4a as a prototype structure of the μ-opioid receptor radioligand. By introducing the new series of [18F]fluorophenylazocarboxylic-tert-butyl esters, the method of 18F-fluoroarylation was significantly expanded, thereby demonstrating the versatility of 18F-labeled phenylazocarboxylates for the design of potential radiotracers for positron emission tomography .
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Affiliation(s)
- Natascha Nebel
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schwabachanlage
6, Erlangen D-91054, Germany
| | - Brigitte Strauch
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schwabachanlage
6, Erlangen D-91054, Germany
| | - Simone Maschauer
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schwabachanlage
6, Erlangen D-91054, Germany
| | - Roman Lasch
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schuhstrasse 19, Erlangen D-91052, Germany
| | - Hannelore Rampp
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schuhstrasse 19, Erlangen D-91052, Germany
| | - Stefanie K. Fehler
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schuhstrasse 19, Erlangen D-91052, Germany
| | - Leonard R. Bock
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schuhstrasse 19, Erlangen D-91052, Germany
| | - Harald Hübner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schuhstrasse 19, Erlangen D-91052, Germany
| | - Peter Gmeiner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schuhstrasse 19, Erlangen D-91052, Germany
| | - Markus R. Heinrich
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schuhstrasse 19, Erlangen D-91052, Germany
| | - Olaf Prante
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg
(FAU), Schwabachanlage
6, Erlangen D-91054, Germany
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33
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Krüll J, Hubert A, Nebel N, Prante O, Heinrich MR. Microwave‐Assisted Rapid One‐Pot Synthesis of Fused and Non‐Fused Indoles and 5‐[
18
F]Fluoroindoles from Phenylazocarboxylates. Chemistry 2017; 23:16174-16178. [DOI: 10.1002/chem.201703890] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Jasmin Krüll
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander Universität Erlangen-Nürnberg Schuhstraße 19 91052 Erlangen Germany
| | - Anja Hubert
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander Universität Erlangen-Nürnberg Schuhstraße 19 91052 Erlangen Germany
| | - Natascha Nebel
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Schwabachanlage 6 91054 Erlangen Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Schwabachanlage 6 91054 Erlangen Germany
| | - Markus R. Heinrich
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander Universität Erlangen-Nürnberg Schuhstraße 19 91052 Erlangen Germany
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34
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Stößel A, Brox R, Purkayastha N, Hübner H, Hocke C, Prante O, Gmeiner P. Development of molecular tools based on the dopamine D 3 receptor ligand FAUC 329 showing inhibiting effects on drug and food maintained behavior. Bioorg Med Chem 2017; 25:3491-3499. [PMID: 28495386 DOI: 10.1016/j.bmc.2017.04.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 04/24/2017] [Accepted: 04/27/2017] [Indexed: 12/18/2022]
Abstract
Dopamine D3 receptor-mediated networks have been associated with a wide range of neuropsychiatric diseases, drug addiction and food maintained behavior, which makes D3 a highly promising biological target. The previously described dopamine D3 receptor ligand FAUC 329 (1) showed protective effects against dopamine depletion in a MPTP mouse model of Parkinson's disease. We used the radioligand [18F]2, a [18F]fluoroethoxy substituted analog of the lead compound 1 as a molecular tool for visualization of D3-rich brain regions including the islands of Calleja. Furthermore, structural modifications are reported leading to the pyrimidylpiperazine derivatives 3 and 9 displaying superior subtype selectivity and preference over serotonergic receptors. Evaluation of the lead compound 1 on cocaine-seeking behavior in non-human primates showed a substantial reduction in cocaine self-administration behavior and food intake.
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Affiliation(s)
- Anne Stößel
- Department of Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University, Schuhstraβe 19, D-91052 Erlangen, Germany
| | - Regine Brox
- Department of Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University, Schuhstraβe 19, D-91052 Erlangen, Germany
| | - Nirupam Purkayastha
- Department of Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University, Schuhstraβe 19, D-91052 Erlangen, Germany
| | - Harald Hübner
- Department of Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University, Schuhstraβe 19, D-91052 Erlangen, Germany
| | - Carsten Hocke
- Department of Nuclear Medicine, Ulmenweg 18, D-91054 Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Ulmenweg 18, D-91054 Erlangen, Germany
| | - Peter Gmeiner
- Department of Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University, Schuhstraβe 19, D-91052 Erlangen, Germany.
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35
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Keller M, Maschauer S, Brennauer A, Tripal P, Koglin N, Dittrich R, Bernhardt G, Kuwert T, Wester HJ, Buschauer A, Prante O. Prototypic 18F-Labeled Argininamide-Type Neuropeptide Y Y 1R Antagonists as Tracers for PET Imaging of Mammary Carcinoma. ACS Med Chem Lett 2017; 8:304-309. [PMID: 28337321 DOI: 10.1021/acsmedchemlett.6b00467] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 02/21/2017] [Indexed: 12/24/2022] Open
Abstract
The neuropeptide Y (NPY) Y1 receptor (Y1R) selective radioligand (R)-Nα-(2,2-diphenylacetyl)-Nω-[4-(2-[18F]fluoropropanoylamino)butyl]aminocarbonyl-N-(4-hydroxybenzyl)argininamide ([18F]23), derived from the high-affinity Y1R antagonist BIBP3226, was developed for imaging studies of Y1R-positive tumors. Starting from the argininamide core bearing amine-functionalized spacer moieties, a series of fluoropropanoylated and fluorobenzoylated derivatives was synthesized and studied for Y1R affinity. The fluoropropanoylated derivative 23 displayed high affinity (Ki = 1.3 nM) and selectivity toward Y1R. Radiosynthesis was accomplished via 18F-fluoropropanoylation, yielding [18F]23 with excellent stability in mice; however, the biodistribution study revealed pronounced hepatobiliary clearance with high accumulation in the gall bladder (>100 %ID/g). Despite the unfavorable biodistribution, [18F]23 was successfully used for imaging of Y1R positive MCF-7 tumors in nude mice. Therefore, we suggest [18F]23 as a lead for the design of PET ligands with optimized physicochemical properties resulting in more favorable biodistribution and higher Y1R-dependent enrichment in mammary carcinoma.
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Affiliation(s)
- Max Keller
- Department
of Pharmaceutical/Medicinal Chemistry II, Faculty of Chemistry and
Pharmacy, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Simone Maschauer
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Albert Brennauer
- Department
of Pharmaceutical/Medicinal Chemistry II, Faculty of Chemistry and
Pharmacy, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Philipp Tripal
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Norman Koglin
- Department
of Pharmaceutical Radiochemistry, Technical University Munich (TUM), Walther-Meißner-Str. 3, D-85748 Garching, Germany
| | - Ralf Dittrich
- Department
of Obstetrics and Gynecology, Friedrich Alexander University Erlangen-Nürnberg (FAU), Universitätsstr. 21/23, D-91054 Erlangen, Germany
| | - Günther Bernhardt
- Department
of Pharmaceutical/Medicinal Chemistry II, Faculty of Chemistry and
Pharmacy, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Torsten Kuwert
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Hans-Jürgen Wester
- Department
of Pharmaceutical Radiochemistry, Technical University Munich (TUM), Walther-Meißner-Str. 3, D-85748 Garching, Germany
| | - Armin Buschauer
- Department
of Pharmaceutical/Medicinal Chemistry II, Faculty of Chemistry and
Pharmacy, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Olaf Prante
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054 Erlangen, Germany
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36
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Schomäcker K, Fischer T, Zimmermanns B, Bregulla J, Sudbrock F, Prante O, Drzezga A. Retention efficacy and release of radioiodine in fume hoods. J Environ Radioact 2017; 166:175-180. [PMID: 26825260 DOI: 10.1016/j.jenvrad.2016.01.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 12/18/2015] [Accepted: 01/12/2016] [Indexed: 06/05/2023]
Abstract
Procedures to determine the release of hazardous gaseous substances including radioactive iodine are covered by different norms such as the European standard EN 14175 and the German national standard DIN 25466. The detection of sulphur hexafluoride (SF6) is required to comply with the prescribed methodology. The detection limit of this test is 4.5·10-7 mol/m3 in exhaust air. This detection limit would represent a very high activity in the region of 0.27 TBq/m3 leading to an unacceptable risk. We therefore developed a test using a filter system, consisting of a combination of filters capable of separating various chemical forms of airborne radioiodine. Air samples were collected directly in front of the fume hood and in the laboratory beside two different fume hoods of a similar construction with a final activated carbon filter for retention of radioiodine. Particular attention was therefore paid to air samples taken after passage over the filters. Significant differences in the degree of retention of iodine were found between the two fume hoods investigated. In one test a malfunction of the fume hood was demonstrated. In this case 0.148 × 10-3% of the total released activity per m3 air was found 1 cm in front of the hood sash. A remarkably high fraction of the activity released in the fume hood (1.3 × 10-3%/m3 air) was measured after the activated carbon filter. In the ambient air, values of up to 8.6 × 10-6% pro m3 laboratory air sampled were measured, despite a 6-8-fold air exchange. The selected procedure is a factor of 1011 (Schomäcker et al., 2001) more sensitive than the standard recommended methods (EN 14175). The standard test prescribed by the DIN/EN failed to reveal any inadequacy in the protective function of the radionuclide hood with respect to radioiodine retention.
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Affiliation(s)
- K Schomäcker
- Department of Nuclear Medicine, University Hospital of Cologne, Germany.
| | - T Fischer
- Department of Nuclear Medicine, University Hospital of Cologne, Germany
| | - B Zimmermanns
- Department of Nuclear Medicine, University Hospital of Cologne, Germany
| | - J Bregulla
- Department of Nuclear Medicine, University Hospital of Cologne, Germany
| | - F Sudbrock
- Department of Nuclear Medicine, University Hospital of Cologne, Germany
| | - O Prante
- Department of Nuclear Medicine, University Hospital Erlangen, Germany
| | - A Drzezga
- Department of Nuclear Medicine, University Hospital of Cologne, Germany
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Maschauer S, Heilmann M, Wängler C, Schirrmacher R, Prante O. Radiosynthesis and Preclinical Evaluation of 18F-Fluoroglycosylated Octreotate for Somatostatin Receptor Imaging. Bioconjug Chem 2016; 27:2707-2714. [PMID: 27715017 DOI: 10.1021/acs.bioconjchem.6b00472] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Short synthetic octapeptide analogs derived from the native somatostatin peptides SST-14 and SST-28, namely, octreotate (TATE) or octreotide (TOC), bind with high affinity to somatostatin receptors (sstr), mainly to subtypes 2 and 5, which are expressed in high density on neuroendocrine tumors (NET). Therefore, radiolabeled TATE or TOC derivatives represent highly valuable imaging probes for NET diagnosis by positron emission tomography (PET). The aim of our study was the development of an 18F-labeled octreotate analog as an alternative radiotracer for the clinically established 68Ga-DOTATOC and 68Ga-DOTATATE. We applied our previously developed method based on copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) to the radiosynthesis of 18F-fluoroglycosylated TATE ([18F]FGlc-TATE). [18F]FGlc-TATE was obtained in high yields of 19-22% (non-decay-corrected, referred to [18F]fluoride) and in high specific activities of 32-106 GBq/μmol. [18F]FGlc-TATE showed high affinity to sstr expressed on AR42J cells (IC50 = 4.2 nM) with fast and high internalization, and a beneficial logD7.4 of -1.8. In AR42J tumor bearing nude mice, [18F]FGlc-TATE showed high and specific tumor uptake of 5.6%ID/g at 60 min post-injection, as determined by blocking experiments using octreotide, and fast clearance from other organs, resulting in excellent tumor-to-blood ratios increasing from 9 to 17 from 30 to 60 min post-injection. Small animal PET studies revealed high uptake of [18F]FGlc-TATE in the tumor which could be blocked with octreotide by >99%. Overall, [18F]FGlc-TATE revealed excellent in vitro and in vivo properties and is therefore a viable alternative 18F-labeled radiopeptide for imaging somatostatin receptor-positive tumors by PET.
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Affiliation(s)
- Simone Maschauer
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University Erlangen-Nürnberg (FAU) , Schwabachanlage 6, 91054 Erlangen, Germany
| | - Marcus Heilmann
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University Erlangen-Nürnberg (FAU) , Schwabachanlage 6, 91054 Erlangen, Germany
| | - Carmen Wängler
- Biomedical Chemistry, Department of Clinical Radiology and Nuclear Medicine Medical Faculty Mannheim of Heidelberg University , Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
| | - Ralf Schirrmacher
- Medical Isotope Cyclotron Facility, Department of Oncology, University of Alberta , 11560 University Avenue, Edmonton, Alberta T6G 1Z2, Canada
| | - Olaf Prante
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University Erlangen-Nürnberg (FAU) , Schwabachanlage 6, 91054 Erlangen, Germany
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Nebel N, Maschauer S, Kuwert T, Hocke C, Prante O. In Vitro and In Vivo Characterization of Selected Fluorine-18 Labeled Radioligands for PET Imaging of the Dopamine D3 Receptor. Molecules 2016; 21:molecules21091144. [PMID: 27589704 PMCID: PMC6272905 DOI: 10.3390/molecules21091144] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 08/25/2016] [Accepted: 08/26/2016] [Indexed: 02/07/2023] Open
Abstract
Cerebral dopamine D3 receptors seem to play a key role in the control of drug-seeking behavior. The imaging of their regional density with positron emission tomography (PET) could thus help in the exploration of the molecular basis of drug addiction. A fluorine-18 labeled D3 subtype selective radioligand would be beneficial for this purpose; however, as yet, there is no such tracer available. The three candidates [18F]1, [18F]2a and [18F]2b were chosen for in vitro and in vivo characterization as radioligands suitable for selective PET imaging of the D3 receptor. Their evaluation included the analysis of radiometabolites and the assessment of non-specific binding by in vitro rat brain autoradiography. While [18F]1 and [18F]2a revealed high non-specific uptake in in vitro rat brain autoradiography, the D3 receptor density was successfully determined on rat brain sections (n = 4) with the candidate [18F]2b offering a Bmax of 20.38 ± 2.67 pmol/g for the islands of Calleja, 19.54 ± 1.85 pmol/g for the nucleus accumbens and 16.58 ± 1.63 pmol/g for the caudate putamen. In PET imaging studies, the carboxamide 1 revealed low signal/background ratios in the rat brain and relatively low uptake in the pituitary gland, while the azocarboxamides [18F]2a and [18F]2b showed binding that was blockable by the D3 receptor ligand BP897 in the ventricular system and the pituitary gland in PET imaging studies in living rats.
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Affiliation(s)
- Natascha Nebel
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen 91054, Germany.
| | - Simone Maschauer
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen 91054, Germany.
| | - Torsten Kuwert
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen 91054, Germany.
| | - Carsten Hocke
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen 91054, Germany.
| | - Olaf Prante
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen 91054, Germany.
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Maschauer S, Einsiedel J, Hübner H, Gmeiner P, Prante O. 18F- and 68Ga-Labeled Neurotensin Peptides for PET Imaging of Neurotensin Receptor 1. J Med Chem 2016; 59:6480-92. [DOI: 10.1021/acs.jmedchem.6b00675] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Simone Maschauer
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander University (FAU), Schwabachanlage 6, 91054 Erlangen, Germany
| | - Jürgen Einsiedel
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University (FAU), Schuhstraße 19, 91052 Erlangen, Germany
| | - Harald Hübner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University (FAU), Schuhstraße 19, 91052 Erlangen, Germany
| | - Peter Gmeiner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University (FAU), Schuhstraße 19, 91052 Erlangen, Germany
| | - Olaf Prante
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander University (FAU), Schwabachanlage 6, 91054 Erlangen, Germany
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Gandesiri M, Chakilam S, Ivanovska J, Benderska N, Ocker M, Di Fazio P, Feoktistova M, Gali-Muhtasib H, Rave-Fränk M, Prante O, Christiansen H, Leverkus M, Hartmann A, Schneider-Stock R. Erratum to: DAPK plays an important role in panobinostat-induced autophagy and commits cells to apoptosis under autophagy deficient conditions. Apoptosis 2016; 21:671-4. [PMID: 26960313 DOI: 10.1007/s10495-016-1224-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Muktheshwar Gandesiri
- Experimental Tumorpathology, Department of Pathology, University of Erlangen-Nürnberg, Universitätsstr. 22, 91054, Erlangen, Germany
| | - Saritha Chakilam
- Experimental Tumorpathology, Department of Pathology, University of Erlangen-Nürnberg, Universitätsstr. 22, 91054, Erlangen, Germany
| | - Jelena Ivanovska
- Experimental Tumorpathology, Department of Pathology, University of Erlangen-Nürnberg, Universitätsstr. 22, 91054, Erlangen, Germany
| | - Natalya Benderska
- Experimental Tumorpathology, Department of Pathology, University of Erlangen-Nürnberg, Universitätsstr. 22, 91054, Erlangen, Germany
| | - Matthias Ocker
- Institute for Surgical Research, Philipps University Marburg, Marburg, Germany
| | - Pietro Di Fazio
- Institute for Surgical Research, Philipps University Marburg, Marburg, Germany
| | - Maria Feoktistova
- Section of Molecular Dermatology, Department of Dermatology, Venereology, and Allergology, Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | | | - Margret Rave-Fränk
- Department of Radiation Oncology, University Hospital Goettingen, Goettingen, Germany
| | - Olaf Prante
- Laboratory of Molecular Imaging, Clinic of Nuclear Medicine, Erlangen, Germany
| | - Hans Christiansen
- Department of Radiation Oncology, University Hospital Goettingen, Goettingen, Germany
- Radiation Therapy and Oncology, Medical School Hanover, Hanover, Germany
| | - Martin Leverkus
- Section of Molecular Dermatology, Department of Dermatology, Venereology, and Allergology, Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Arndt Hartmann
- Experimental Tumorpathology, Department of Pathology, University of Erlangen-Nürnberg, Universitätsstr. 22, 91054, Erlangen, Germany
| | - Regine Schneider-Stock
- Experimental Tumorpathology, Department of Pathology, University of Erlangen-Nürnberg, Universitätsstr. 22, 91054, Erlangen, Germany.
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Nebel N, Maschauer S, Hocke C, Hübner H, Gmeiner P, Prante O. Optimization and synthesis of an (18) F-labeled dopamine D3 receptor ligand using [(18) F]fluorophenylazocarboxylic tert-butylester. J Labelled Comp Radiopharm 2015; 59:48-53. [PMID: 26707848 DOI: 10.1002/jlcr.3361] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 11/17/2015] [Indexed: 12/29/2022]
Abstract
There is still no efficient fluorine-18-labeled dopamine D3 subtype selective receptor ligand for studies with positron emission tomography. We aim at improving the D3 selectivity and hydrophilicity of a candidate ligand by changing the substitution pattern to a 2,3-dichlorophenylpiperazine and hydroxylation of the butyl chain. The compound [(18) F]3 exhibited D3 affinity of Ki = 3.6 nM, increased subtype selectivity (Ki (D2 /D3 ) = 60), and low affinity to 5-HT1A and α1 receptors (Ki (5-HT1A /D3 ) = 34; Ki (α1 /D3 ) = 100). The two-step radiosynthesis was optimized for analog [(18) F]4 by reducing the necessary concentration of the precursor amine (57 mM), which reacted with [(18) F]fluorophenylazocarboxylic tert-butylester under basic conditions. The optimization of the base (Cs 2 CO3 , 23 mM) and the adjustment of reaction temperature led to the radiochemical yield of 63% after 5 min at 35°C. The optimized reaction conditions were transferred on to the synthesis of [(18) F]3 with an overall non-decay corrected yield of 8-12% in a specific activity of 32-102 GBq/µmol after a total synthesis time of 30-35 min. This provides a D 3 radioligand candidate with improved attributes concerning selectivity and radiosynthesis for further preclinical studies.
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Affiliation(s)
- Natascha Nebel
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054, Erlangen, Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054, Erlangen, Germany
| | - Carsten Hocke
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054, Erlangen, Germany
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schuhstrasse 19, D-91052, Erlangen, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schuhstrasse 19, D-91052, Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, D-91054, Erlangen, Germany
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Maschauer S, Gahr S, Gandesiri M, Tripal P, Schneider-Stock R, Kuwert T, Ocker M, Prante O. In vivo monitoring of the anti-angiogenic therapeutic effect of the pan-deacetylase inhibitor panobinostat by small animal PET in a mouse model of gastrointestinal cancers. Nucl Med Biol 2015; 43:27-34. [PMID: 26702784 DOI: 10.1016/j.nucmedbio.2015.10.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 09/29/2015] [Accepted: 10/16/2015] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Deacetylase inhibitors have recently been established as a novel therapeutic approach to solid and hematologic cancers and have also been demonstrated to possess anti-angiogenic properties. Although these compounds show a good efficacy in vitro and in vivo, no data on monitoring and predicting treatment response are currently available. We therefore investigated the effect of the pan-deacetylase inhibitor panobinostat (LBH589) on gastrointestinal cancer models and the suitability of 2-[(18)F]FGlc-RGD as a specific agent for imaging integrin αvβ3 expression during tumor angiogenesis using small animal positron emission tomography (PET). METHODS The effect of panobinostat on cell viability in vitro was assessed with a label-free impedance based real-time analysis. Nude mice bearing HT29 and HepG2 tumors were treated with daily i.p. injections of 10mg/kg panobinostat for 4 weeks. During this time, tumor size was determined with a calliper and mice were repeatedly subjected to PET imaging. Tumor tissues were analyzed immunohistochemically with a focus on proliferation and endothelial cell markers (Ki-67, Meca-32) and by Western blot applying specific markers of apoptosis. RESULTS In vitro, panobinostat inhibited the proliferation of HepG2 and HT29 cells. Contrary to the situation in HepG2 tumors in vivo, where panobinostat treatment is known to reduce proliferation and vascularization resulting in a decreased tumor growth, HT29 tumors did not show any effect on these parameters. We demonstrated by Western blotting, that panobinostat induced apoptosis in HT29 tumors in vivo. Longitudinal PET imaging studies in HepG2 tumor-bearing mice using 2-[(18)F]FGlc-RGD demonstrated that the standard uptake value (SUVmax) in HepG2 tumors was significantly decreased by 39% at day 7 after treatment. The comparative PET study using HT29 tumor-bearing animals did not reveal any response of the tumors to panobinostat treatment. CONCLUSIONS Small-animal PET imaging using 2-[(18)F]FGlc-RGD was successfully applied to the non-invasive monitoring of the HepG2-tumor response to panobinostat in nude mice early after begin of treatment. Thus, PET imaging of angiogenesis using 2-[(18)F]FGlc-RGD could be a valuable tool to monitor panobinostat therapy in further preclinical studies. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE When successfully translated to the clinical surrounding, PET imaging of angiogenesis could therefore facilitate therapy planning and monitoring of therapy success with panobinostat in hepatocellular carcinoma.
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Affiliation(s)
- Simone Maschauer
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Susanne Gahr
- Department of Medicine 1, University Hospital Erlangen, Erlangen, Germany
| | - Muktheshwar Gandesiri
- Experimental Tumorpathology, Department of Pathology, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Philipp Tripal
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Regine Schneider-Stock
- Experimental Tumorpathology, Department of Pathology, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Torsten Kuwert
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Matthias Ocker
- Department of Medicine 1, University Hospital Erlangen, Erlangen, Germany.
| | - Olaf Prante
- Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University (FAU), Erlangen, Germany.
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Maschauer S, Haller A, Riss PJ, Kuwert T, Prante O, Cumming P. Specific binding of [(18)F]fluoroethyl-harmol to monoamine oxidase A in rat brain cryostat sections, and compartmental analysis of binding in living brain. J Neurochem 2015; 135:908-17. [PMID: 26386360 DOI: 10.1111/jnc.13370] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Revised: 09/08/2015] [Accepted: 09/10/2015] [Indexed: 11/28/2022]
Abstract
We investigated [(18)F]fluoroethyl-harmol ([(18)F]FEH) as a reversible and selective ligand for positron emission tomography (PET) studies of monoamine oxidase A (MAO-A). Binding of [(18)F]FEH in rat brain cryostat sections indicated high affinity (KD = 3 nM), and density (Bmax; 600 pmol/g). The plasma free fraction was 45%, and untransformed parent constituted only 13% of plasma radioactivity at 10 min after injection. Compartmental analysis of PET recordings in pargyline-treated rats showed high permeability to brain (K1; 0.32 mL/g/min) and slow washout (k2; 0.024/min), resulting in a uniformly high equilibrium distribution volume (VD; 20 mL/g). Using this VD to estimate unbound ligand in brain of untreated rats, the binding potential ranged from 4.2 in cerebellum to 7.2 in thalamus. We also calculated maps of rats receiving [(18)F]FEH at a range of specific activities, and then estimated saturation binding parameters in the living brain. In thalamus, striatum and frontal cortex KD was globally close to 300 nM and Bmax was close to 1600 pmol/g; the 100-fold discrepancy in affinity suggests a very low free fraction for [(18)F]FEH in the living brain. Based on a synthesis of findings, we calculate the endogenous dopamine concentration to be 0.4 μM in the striatal compartment containing MAO-A, thus unlikely to exert competition against [(18)F]FEH binding in vivo. In summary, [(18)F]FEH has good properties for the detection of MAO-A in the rat brain by PET, and may present logistic advantages for clinical research at centers lacking a medical cyclotron. We made a compartmental analysis of [(18)F]fluoroethylharmol ([(18)F]FEH) binding to monoamine oxidase A (MAO-A) in living rat brain and estimated the saturation binding parameters from the binding potential (BPND). The Bmax was of comparable magnitude to that in vitro, but with apparent affinity (300 nM), it was 100-fold lower in vivo. PET imaging with [(18) F]FEH is well suited for quantitation of MAO-A in living brain.
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Affiliation(s)
- Simone Maschauer
- Laboratory of Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University, Erlangen, Germany
| | - Adelina Haller
- Laboratory of Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University, Erlangen, Germany
| | - Patrick J Riss
- Department of Chemistry, Universitetet i Oslo & Norsk Medisinisk Syklotronsenter AS, Oslo, Norway
| | - Torsten Kuwert
- Laboratory of Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University, Erlangen, Germany
| | - Olaf Prante
- Laboratory of Molecular Imaging and Radiochemistry, Department of Nuclear Medicine, Friedrich Alexander University, Erlangen, Germany
| | - Paul Cumming
- Department of Neuroscience and Pharmacology, Copenhagen University, Copenhagen, Denmark.,Department of Neuropsychiatry and Psychosomatic Medicine, OUS-Rikshospitalet, Oslo, Norway
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Maschauer S, Greff C, Einsiedel J, Ott J, Tripal P, Hübner H, Gmeiner P, Prante O. Improved radiosynthesis and preliminary in vivo evaluation of a 18F-labeled glycopeptide–peptoid hybrid for PET imaging of neurotensin receptor 2. Bioorg Med Chem 2015; 23:4026-33. [DOI: 10.1016/j.bmc.2015.01.053] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 01/28/2015] [Accepted: 01/29/2015] [Indexed: 12/14/2022]
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Hofmann S, Maschauer S, Kuwert T, Beck-Sickinger AG, Prante O. Synthesis and in vitro and in vivo evaluation of an (18)F-labeled neuropeptide Y analogue for imaging of breast cancer by PET. Mol Pharm 2015; 12:1121-30. [PMID: 25748228 DOI: 10.1021/mp500601z] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Imaging of Y1R expression in breast cancer is still a challenging task. Herein, we report a suitable (18)F-labeled high-molecular-weight glycopeptide for imaging of peripheral neuropeptide Y (NPY) Y1 receptor (Y1R)-positive tumors by preclinical small-animal positron emission tomography (PET). The Y1R-preferring NPY [F(7),P(34)]NPY analogue was functionalized with an alkyne-bearing propargylglycine (Pra) in position 4. The corresponding fluoroglycosylated (FGlc) peptide analogue [Pra(4)(FGlc),F(7),P(34)]NPY and its (18)F-labeled analogue were synthesized by click chemistry-based fluoroglycosylation. The radiosynthesis was performed by (18)F-fluoroglycosylation starting from the 2-triflate of the β-mannosylazide and the alkyne peptide [Pra(4),F(7),P(34)]NPY. The radiosynthesis of the(18)F-labeled analogue was optimized using a minimum amount of peptide precursor (40 nmol), proceeding with an overall radiochemical yield of 20-25% (nondecay corrected) in a total synthesis time of 75 min with specific activities of 40-70 GBq/μmol. In comparison to NPY and [F(7),P(34)]NPY, in vitro Y1R and Y2R activation studies with the cold [Pra(4)(FGlc),F(7),P(34)]NPY on stably transfected COS-7 cells displayed a high potency for the induction of Y1R-specific inositol accumulation (pEC50 = 8.5 ± 0.1), whereas the potency at Y2R was significantly decreased. Internalization studies on stably transfected HEK293 cells confirmed a strong glycopeptide-mediated Y1R internalization and a substantial Y1R subtype selectivity over Y2R. In vitro autoradiography with Y1R-positive MCF-7 tumor tissue slices indicated high specific binding of the (18)F-labeled glycopeptide, when binding was reduced by 95% ([Pra(4),F(7),P(34)]NPY) and by 86% (BIBP3226 Y1R antagonist) in competition studies. Biodistribution and small-animal PET studies on MCF-7 breast tumor-bearing nude mice revealed radiotracer uptake in the MCF-7 tumor of 1.8%ID/g at 20 min p.i. and 0.7%ID/g at 120 min p.i. (n = 3-4), increasing tumor-to-blood ratios from 1.2 to 2.4, and a tumor retention of 76 ± 4% (n = 4; 45-90 min p.i.). PET imaging studies with MCF-7 tumor-bearing nude mice demonstrated uptake of the (18)F-labeled glycopeptide in the tumor region at 60 min p.i., whereas only negligible tumor uptake was observed in animals injected with a nonbinding (18)F-labeled glycopeptide pendant as a measure of nonspecific binding. In conclusion, PET imaging experiments with the (18)F-labeled NPY glycopeptide revealed Y1R-specific binding uptake in MCF-7 tumors in vivo together with decreased kidney uptake compared to DOTA-derivatives of this peptide. We consider this glycopeptide to be a potent lead peptide for the design of improved (18)F-glycopeptides with shorter amino acid sequences that would further facilitate PET imaging studies of Y1R-positive breast tumors.
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Affiliation(s)
- Sven Hofmann
- †Faculty of Biosciences, Pharmacy and Psychology, Institute of Biochemistry, Universität Leipzig, 04109 Leipzig, Germany
| | - Simone Maschauer
- ‡Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Torsten Kuwert
- ‡Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Annette G Beck-Sickinger
- †Faculty of Biosciences, Pharmacy and Psychology, Institute of Biochemistry, Universität Leipzig, 04109 Leipzig, Germany
| | - Olaf Prante
- ‡Department of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
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Cumming P, Skaper D, Kuwert T, Maschauer S, Prante O. Detection of monoamine oxidase a in brain of living rats with [18F]fluoroethyl-harmol PET. Synapse 2014; 69:57-9. [DOI: 10.1002/syn.21785] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 08/25/2014] [Accepted: 09/11/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Paul Cumming
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
- Department of Neuroscience and Pharmacology; Copenhagen University; Copenhagen Denmark
| | - Dirk Skaper
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry; Friedrich Alexander University Erlangen-Nürnberg (FAU); Erlangen Germany
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Sparr C, Purkayastha N, Yoshinari T, Seebach D, Maschauer S, Prante O, Hübner H, Gmeiner P, Kolesinska B, Cescato R, Waser B, Reubi JC. Syntheses, receptor bindings, in vitro and in vivo stabilities and biodistributions of DOTA-neurotensin(8-13) derivatives containing β-amino acid residues - a lesson about the importance of animal experiments. Chem Biodivers 2014; 10:2101-21. [PMID: 24327436 DOI: 10.1002/cbdv.201300331] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Indexed: 12/11/2022]
Abstract
Neurotensin(8-13) (NTS(8-13)) analogs with C- and/or N-terminal β-amino acid residues and three DOTA derivatives thereof have been synthesized (i.e., 1-6). A virtual docking experiment showed almost perfect fit of one of the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) derivatives, 6a, into a crystallographically identified receptor NTSR1 (Fig.1). The affinities for the receptors of the NTS analogs and derivatives are low, when determined with cell-membrane homogenates, while, with NTSR1-exhibiting cancer tissues, affinities in the single-digit nanomolar range can be observed (Table 2). Most of the β-amino acid-containing NTS(8-13) analogs (Table 1 and Fig.2), including the (68) Ga complexes of the DOTA-substituted ones (6; Figs.2 and 5), are stable for ca. 1 h in human serum and plasma, and in murine plasma. The biodistributions of two (68) Ga complexes (of 6a and 6b) in HT29 tumor-bearing nude mice, in the absence and in the presence of a blocking compound, after 10, 30, and 60 min (Figs. 3 and 4) lead to the conclusion that the amount of specifically bound radioligand is rather low. This was confirmed by PET-imaging experiments with the tumor-bearing mice (Fig.6). Comparison of the in vitro plasma stability (after 1 h) with the ex vivo blood content (after 10-15 min) of the two (68) Ga complexes shows that they are rapidly cleaved in the animals (Fig.5).
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Affiliation(s)
- Christof Sparr
- Laboratorium für Organische Chemie, Departement Chemie und Angewandte Biowissenschaften, ETH-Zürich, Hönggerberg HCI, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, (phone: +41-44-632-2990; fax: +41-44-632-1144)
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Prante O, Maschauer S, Banerjee A. Radioligands for the dopamine receptor subtypes. J Labelled Comp Radiopharm 2014; 56:130-48. [PMID: 24285319 DOI: 10.1002/jlcr.3000] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 10/11/2012] [Accepted: 11/06/2012] [Indexed: 12/29/2022]
Abstract
The actions of the predominant neurotransmitter in the brain, dopamine, are mediated by the postsynaptic dopamine receptors. The five dopamine receptor subtypes and their regulation have been associated with a large variety of psychiatric diseases. Therefore, positron emission tomography (PET) imaging studies using suitable and selective (18) F-labeled and (11) C-labeled dopamine receptor radioligands could provide valuable knowledge on the impact of receptor density on the pathogenesis and evolvement of neuropsychiatric and neurological diseases. This special issue subchapter provides a summary of the most important (18) F-labeled and (11) C-labeled radioligands for PET imaging of the dopamine receptor subtypes, their radiochemistry, and characteristics from in vitro and in vivo applications, considering not only the already established PET ligands but also the recently published preclinical work.
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Affiliation(s)
- Olaf Prante
- Laboratory of Molecular Imaging and Radiochemistry, Friedrich-Alexander University, Schwabachanlage 6, D-91054, Erlangen, Germany
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Cumming P, Maschauer S, Riss PJ, Tschammer N, Fehler SK, Heinrich MR, Kuwert T, Prante O. Radiosynthesis and validation of ¹⁸F-FP-CMT, a phenyltropane with superior properties for imaging the dopamine transporter in living brain. J Cereb Blood Flow Metab 2014; 34:1148-56. [PMID: 24714035 PMCID: PMC4083377 DOI: 10.1038/jcbfm.2014.63] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 02/19/2014] [Accepted: 03/16/2014] [Indexed: 01/21/2023]
Abstract
To date there is no validated, (18)F-labeled dopamine transporter (DAT) radiotracer with a rapid kinetic profile suitable for preclinical small-animal positron emission tomography (PET) studies in rodent models of human basal ganglia disease. Herein we report radiosynthesis and validation of the phenyltropane (18)F-FP-CMT. Dynamic PET recordings were obtained for (18)F-FP-CMT in six untreated rats, and six rats pretreated with the high-affinity DAT ligand GBR 12909; mean parametric maps of binding potential (BPND) relative to the cerebellum reference region, and maps of total distribution volume (VT) relative to the metabolite-corrected arterial input were produced. (18)F-FP-CMT BPND maps showed peak values of ∼4 in the striatum, versus ∼0.4 in the vicinity of the substantia nigra. Successive truncation of the PET recordings indicated that stable BPND estimates could be obtained with recordings lasting only 45 minutes, reflecting rapid kinetics of (18)F-FP-CMT. Pretreatment with GBR 12909 reduced the striatal binding by 72% to 76%. High-performance liquid chromatography analysis revealed rapid metabolism of (18)F-FP-CMT to a single, non-brain penetrant hydrophilic metabolite. Total distribution of volume calculated relative to the metabolite-corrected arterial input was 4.4 mL/g in the cerebellum. The pharmacological selectivity of (18)F-FP-CMT, rapid kinetic profile, and lack of problematic metabolites constitute optimal properties for quantitation of DAT in rat, and may also predict applicability in human PET studies.
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Affiliation(s)
- Paul Cumming
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Erlangen, Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Erlangen, Germany
| | - Patrick J Riss
- Department of Chemistry, Universitetet i Oslo & Norsk Medisinisk Syklotronsenter AS, Oslo, Norway
| | - Nuska Tschammer
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry, Emil Fischer Center, Friedrich Alexander University, Erlangen, Germany
| | - Stefanie K Fehler
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry, Emil Fischer Center, Friedrich Alexander University, Erlangen, Germany
| | - Markus R Heinrich
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry, Emil Fischer Center, Friedrich Alexander University, Erlangen, Germany
| | - Torsten Kuwert
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Erlangen, Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Erlangen, Germany
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Maschauer S, Ruckdeschel T, Tripal P, Haubner R, Einsiedel J, Hübner H, Gmeiner P, Kuwert T, Prante O. In vivo monitoring of the antiangiogenic effect of neurotensin receptor-mediated radiotherapy by small-animal positron emission tomography: a pilot study. Pharmaceuticals (Basel) 2014; 7:464-81. [PMID: 24743103 PMCID: PMC4014703 DOI: 10.3390/ph7040464] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 04/04/2014] [Accepted: 04/10/2014] [Indexed: 12/22/2022] Open
Abstract
The neurotensin receptor (NTS1) has emerged as an interesting target for molecular imaging and radiotherapy of NTS-positive tumors due to the overexpression in a range of tumors. The aim of this study was to develop a 177Lu-labeled NTS1 radioligand, its application for radiotherapy in a preclinical model and the imaging of therapy success by small-animal positron emission tomography (µPET) using [68Ga]DOTA-RGD as a specific tracer for imaging angiogenesis. The 177Lu-labeled peptide was subjected to studies on HT29-tumor-bearing nude mice in vivo, defining four groups of animals (single dose, two fractionated doses, four fractionated doses and sham-treated animals). Body weight and tumor diameters were determined three times per week. Up to day 28 after treatment, µPET studies were performed with [68Ga]DOTA-RGD. At days 7–10 after treatment with four fractionated doses of 11–14 MBq (each at days 0, 3, 6 and 10), the tumor growth was slightly decreased in comparison with untreated animals. Using a single high dose of 51 MBq, a significantly decreased tumor diameter of about 50% was observed with the beginning of treatment. Our preliminary PET imaging data suggested decreased tumor uptake values of [68Ga]DOTA-RGD in treated animals compared to controls at day 7 after treatment. This pilot study suggests that early PET imaging with [68Ga]DOTA-RGD in radiotherapy studies to monitor integrin expression could be a promising tool to predict therapy success in vivo. Further successive PET experiments are needed to confirm the significance and predictive value of RGD-PET for NTS-mediated radiotherapy.
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Affiliation(s)
- Simone Maschauer
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Schwabachanlage 6, 91054 Erlangen, Germany.
| | - Tina Ruckdeschel
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Schwabachanlage 6, 91054 Erlangen, Germany.
| | - Philipp Tripal
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Schwabachanlage 6, 91054 Erlangen, Germany.
| | - Roland Haubner
- Department of Nuclear Medicine, Innsbruck Medical University, Anichstr. 35, 6020 Innsbruck, Austria.
| | - Jürgen Einsiedel
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University, Schuhstraße 19, 91052 Erlangen, Germany.
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University, Schuhstraße 19, 91052 Erlangen, Germany.
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University, Schuhstraße 19, 91052 Erlangen, Germany.
| | - Torsten Kuwert
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Schwabachanlage 6, 91054 Erlangen, Germany.
| | - Olaf Prante
- Department of Nuclear Medicine, Laboratory of Molecular Imaging and Radiochemistry, Friedrich Alexander University, Schwabachanlage 6, 91054 Erlangen, Germany.
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