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Sweetening Pharmaceutical Radiochemistry by 18F-Fluoroglycosylation: Recent Progress and Future Prospects. Pharmaceuticals (Basel) 2021; 14:ph14111175. [PMID: 34832957 PMCID: PMC8621802 DOI: 10.3390/ph14111175] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/11/2021] [Accepted: 11/15/2021] [Indexed: 12/11/2022] Open
Abstract
In the field of 18F-chemistry for the development of radiopharmaceuticals for positron emission tomography (PET), various labeling strategies by the use of prosthetic groups have been implemented, including chemoselective 18F-labeling of biomolecules. Among those, chemoselective 18F-fluoroglycosylation methods focus on the sweetening of pharmaceutical radiochemistry by offering a highly valuable tool for the synthesis of 18F-glycoconjugates with suitable in vivo properties for PET imaging studies. A previous review covered the various 18F-fluoroglycosylation methods that were developed and applied as of 2014 (Maschauer and Prante, BioMed. Res. Int. 2014, 214748). This paper is an updated review, providing the recent progress in 18F-fluoroglycosylation reactions and the preclinical application of 18F-glycoconjugates, including small molecules, peptides, and high-molecular-weight proteins.
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Lv G, Miao Y, Chen Y, Lu C, Wang X, Xie M, Qiu L, Lin J. Promising potential of a 18F-labelled small-molecular radiotracer to evaluate PD-L1 expression in tumors by PET imaging. Bioorg Chem 2021; 115:105294. [PMID: 34426150 DOI: 10.1016/j.bioorg.2021.105294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/15/2021] [Accepted: 08/17/2021] [Indexed: 12/20/2022]
Abstract
Programmed death ligand 1 (PD-L1) expression level is a reproducible biomarker for guiding stratification of patients to immunotherapy. However, the most widely used immunohistochemistry method is incompetent to fully understand the PD-L1 expression level in the whole body because of the highly complex PD-L1 expression in the tumor microenvironment. In this work, a novel small-molecular radiotracer [18F]LG-1 based on the biphenyl active structure was developed to evaluate PD-L1 expression in tumors. [18F]LG-1 was obtained by conjugating and radiolabeling with [18F]FDG with high radiochemical purity (>98.0%) and high molar activity (37.2 ± 2.9 MBq/nmol). In vitro experimental results showed that [18F]LG-1 could target PD-L1 in tumor cells and the cellular uptake in A375-hPD-L1 cells (PD-L1 + ) was clearly higher than that in A375 cells (PD-L1-). In vivo dynamic PET images of [18F]LG-1 provided clear visualization of A375-hPD-L1 tumor with high tumor-to-background contrast, and the tumor uptake was determined to be 3.98 ± 0.21 %ID/g at 60 min, which was 2.6-fold higher than that of A375 tumor. These results suggested that [18F]LG-1 had great potential as a promising PD-L1 radiotracer.
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Affiliation(s)
- Gaochao Lv
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Yinxing Miao
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Yinfei Chen
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Chunmei Lu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Xiuting Wang
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Minhao Xie
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Ling Qiu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China.
| | - Jianguo Lin
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China.
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Rangger C, Haubner R. Radiolabelled Peptides for Positron Emission Tomography and Endoradiotherapy in Oncology. Pharmaceuticals (Basel) 2020; 13:E22. [PMID: 32019275 PMCID: PMC7169460 DOI: 10.3390/ph13020022] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 02/07/2023] Open
Abstract
This review deals with the development of peptide-based radiopharmaceuticals for the use with positron emission tomography and peptide receptor radiotherapy. It discusses the pros and cons of this class of radiopharmaceuticals as well as the different labelling strategies, and summarises approaches to optimise metabolic stability. Additionally, it presents different target structures and addresses corresponding tracers, which are already used in clinical routine or are being investigated in clinical trials.
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Affiliation(s)
| | - Roland Haubner
- Department of Nuclear Medicine, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria;
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Yang X, Wang F, Zhu H, Yang Z, Chu T. Synthesis and Bioevaluation of Novel [18F]FDG-Conjugated 2-Nitroimidazole Derivatives for Tumor Hypoxia Imaging. Mol Pharm 2019; 16:2118-2128. [PMID: 30964298 DOI: 10.1021/acs.molpharmaceut.9b00075] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Xianteng Yang
- Guizhou University School of Medicine, Guiyang, Guizhou 550025, China
- Department of Orthopaedics, Guizhou Provincial People’s Hospital, Guiyang, Guizhou 550002, China
| | - Fan Wang
- Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Hua Zhu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Zhi Yang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Taiwei Chu
- Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
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Keinänen O, Partelová D, Alanen O, Antopolsky M, Sarparanta M, Airaksinen AJ. Efficient cartridge purification for producing high molar activity [ 18F]fluoro-glycoconjugates via oxime formation. Nucl Med Biol 2018; 67:27-35. [PMID: 30380464 DOI: 10.1016/j.nucmedbio.2018.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/29/2018] [Accepted: 10/07/2018] [Indexed: 11/18/2022]
Abstract
INTRODUCTION 18F-fluoroglycosylation via oxime formation is a chemoselective and mild radiolabeling method for sensitive molecules. Glycosylation can also improve the bioavailability, in vivo kinetics, and stability of the compound in blood, as well as accelerate clearance of biomolecules. A typical synthesis procedure for 18F-fluoroglycosylation with [18F]FDG (2-deoxy-2-[18F]fluoro-d-glucose) and [18F]FDR (5-deoxy-5-[18F]fluoro-d-ribose) involves two HPLC (high performance liquid chromatography) purifications: one after 18F-fluorination of the carbohydrate to remove its labeling precursor, and a second one after the oxime formation step to remove the aminooxy precursor. The two HPLC purifications can be time consuming and complicate the adaptation of the synthetic strategy in nuclear medicine applications and automated synthesis. We have developed a procedure in which SPE (solid phase extraction) and resin purification methods replace both of the needed HPLC purification steps. METHODS We used [18F]FDR and [18F]FDG as prosthetic groups to radiolabel two aminooxy-modified model molecules, a tetrazine and a PSMA (prostate specific membrane antigen) inhibitor. After fluorination, the excess carbohydrate precursor was removed by derivatizing it with 4,4'-dimethoxytrityl chloride (DMT-Cl). The DMT moiety increases the hydrophobicity of the unreacted precursor making the separation from the fluorinated precursor possible with simple C18 Sep-Pak cartridge. For removal of the aminooxy precursor, we used a commercially available aldehyde resin (AminoLink, Thermo Fisher Scientific). C18 Sep-Pak SPE cartridge was used to separate [18F]FDR and [18F]FDG from the 18F-fluoroglycoconjugate end product. RESULTS [18F]FDR and [18F]FDG were efficiently purified from their precursors, free fluorine-18, and other impurities. The aldehyde resin quantitatively removed the unreacted aminooxy precursors after the oxime formation. The fluorine-18 labeled oxime end products were obtained with high radiochemical purity (>99%) and molar activity (>600 GBq μmol-1). CONCLUSIONS We have developed an efficient cartridge purification method for producing high molar activity 18F-glycoconjugates synthesized via oxime formation.
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Affiliation(s)
- Outi Keinänen
- Department of Chemistry - Radiochemistry, University of Helsinki, Helsinki, Finland
| | - Denisa Partelová
- Department of Chemistry - Radiochemistry, University of Helsinki, Helsinki, Finland; Department of Ecochemistry and Radioecology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius in Trnava, Trnava, Slovakia
| | - Osku Alanen
- Department of Chemistry - Radiochemistry, University of Helsinki, Helsinki, Finland
| | - Maxim Antopolsky
- Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Mirkka Sarparanta
- Department of Chemistry - Radiochemistry, University of Helsinki, Helsinki, Finland
| | - Anu J Airaksinen
- Department of Chemistry - Radiochemistry, University of Helsinki, Helsinki, Finland.
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Bucerius J, Dijkgraaf I, Mottaghy FM, Schurgers LJ. Target identification for the diagnosis and intervention of vulnerable atherosclerotic plaques beyond 18F-fluorodeoxyglucose positron emission tomography imaging: promising tracers on the horizon. Eur J Nucl Med Mol Imaging 2018; 46:251-265. [PMID: 30302506 PMCID: PMC6267660 DOI: 10.1007/s00259-018-4176-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 09/18/2018] [Indexed: 12/11/2022]
Abstract
Cardiovascular disease is the major cause of morbidity and mortality in developed countries and atherosclerosis is the major cause of cardiovascular disease. Atherosclerotic lesions obstruct blood flow in the arterial vessel wall and can rupture leading to the formation of occlusive thrombi. Conventional diagnostic tools are still of limited value for identifying the vulnerable arterial plaque and for predicting its risk of rupture and of releasing thromboembolic material. Knowledge of the molecular and biological processes implicated in the process of atherosclerosis will advance the development of imaging probes to differentiate the vulnerable plaque. The development of imaging probes with high sensitivity and specificity in identifying high-risk atherosclerotic vessel wall changes and plaques is crucial for improving knowledge-based decisions and tailored individual interventions. Arterial PET imaging with 18F-FDG has shown promising results in identifying inflammatory vessel wall changes in numerous studies and clinical trials. However, due to its limited specificity in general and its intense physiological uptake in the left ventricular myocardium that impair imaging of the coronary arteries, different PET tracers for the molecular imaging of atherosclerosis have been evaluated. This review describes biological, chemical and medical expertise supporting a translational approach that will enable the development of new or the evaluation of existing PET tracers for the identification of vulnerable atherosclerotic plaques for better risk prediction and benefit to patients.
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Affiliation(s)
- Jan Bucerius
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center (MUMC+), 6229 HX, Maastricht, The Netherlands. .,Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Center (MUMC+), 6200 MD, Maastricht, The Netherlands. .,Department of Nuclear Medicine, University Hospital RWTH Aachen, Aachen, Germany.
| | - Ingrid Dijkgraaf
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Center (MUMC+), 6200 MD, Maastricht, The Netherlands.,Department of Biochemistry, Maastricht University, Maastricht, The Netherlands
| | - Felix M Mottaghy
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center (MUMC+), 6229 HX, Maastricht, The Netherlands.,Department of Nuclear Medicine, University Hospital RWTH Aachen, Aachen, Germany
| | - Leon J Schurgers
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Center (MUMC+), 6200 MD, Maastricht, The Netherlands. .,Department of Biochemistry, Maastricht University, Maastricht, The Netherlands.
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Rezaeianpour S, Mosayebnia M, Moghimi A, Amidi S, Geramifar P, Kobarfard F, Shahhosseini S. [ 18F]FDG-Labeled CGPRPPC Peptide Serving as a Small Thrombotic Lesions Probe, Including a Comparison with [ 99mTc]-Labeled Form. Cancer Biother Radiopharm 2018; 33:438-444. [PMID: 30234382 DOI: 10.1089/cbr.2018.2515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Purpose: Fibrin is a perfect target for specific imaging of all types of thrombotic lesions. Cyclic peptides were introduced as the best scaffolds out of the different types of probes for thrombi detection. This study was conducted to label previously synthesized peptide-targeting fibrin with [18F]FDG and its in vitro and in vivo assessments. Materials and Methods: CGPRPPC peptide functionalized with 6-hydrazinonicotinamide and Eei-NHS was synthesized and cyclized using air oxidation method. The cyclic sequences were labeled with [18F]FDG at 85°C within 30 min. The stability studies were performed in human plasma. Fibrin-binding and platelet aggregation tests were performed in vitro. Biodistribution and scintigraphy imaging in normal mice and carotid thrombotic rat model were considered as in vivo studies. Results: Radiolabeled peptides show a good stability in human plasma and also high-affinity binding for human fibrin. Platelet aggregation test confirmed specific binding of radiopeptides to fibrin. A key problem with the authors' previous research was inability to detect small-vessel thrombi. The results of positron emission tomography/computed tomography scanning show high specific uptake of [18F]FDG-labeled CGPRPPC in small-sized thrombosis. Conclusion: The experiment revealed that radiolabeling of cyclic peptide (CGPRPPC) with [18F]FDG enables us to detect small thrombotic lesions in small animal models with high resolution.
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Affiliation(s)
- Sedigheh Rezaeianpour
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mona Mosayebnia
- Department of Radiopharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Abolghasem Moghimi
- Faculty of Chemistry, Tehran North Branch Islamic Azad University, Tehran, Iran
| | - Salimeh Amidi
- Department of Pharmaceutical Chemistry and Radiopharmacy, School of Pharmacy, Shahid Behesti University of Medical Sciences, Tehran, Iran
| | - Parham Geramifar
- Research Center for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Farzad Kobarfard
- Department of Pharmaceutical Chemistry and Radiopharmacy, School of Pharmacy, Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Soraya Shahhosseini
- Department of Pharmaceutical Chemistry and Radiopharmacy, School of Pharmacy, and Protein Technology Research Center, Shahid Behesti University of Medical Sciences, Tehran, Iran
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8
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Wei W, Ehlerding EB, Lan X, Luo Q, Cai W. PET and SPECT imaging of melanoma: the state of the art. Eur J Nucl Med Mol Imaging 2018; 45:132-150. [PMID: 29085965 PMCID: PMC5700861 DOI: 10.1007/s00259-017-3839-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/18/2017] [Indexed: 12/12/2022]
Abstract
Melanoma represents the most aggressive form of skin cancer, and its incidence continues to rise worldwide. 18F-FDG PET imaging has transformed diagnostic nuclear medicine and has become an essential component in the management of melanoma, but still has its drawbacks. With the rapid growth in the field of nuclear medicine and molecular imaging, a variety of promising probes that enable early diagnosis and detection of melanoma have been developed. The substantial preclinical success of melanin- and peptide-based probes has recently resulted in the translation of several radiotracers to clinical settings for noninvasive imaging and treatment of melanoma in humans. In this review, we focus on the latest developments in radiolabeled molecular imaging probes for melanoma in preclinical and clinical settings, and discuss the challenges and opportunities for future development.
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Affiliation(s)
- Weijun Wei
- Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600# Yishan Road, Shanghai, 200233, China
- Department of Radiology, University of Wisconsin-Madison, Room 7137, 1111 Highland Avenue, Madison, WI, 53705-2275, USA
| | - Emily B Ehlerding
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Xiaoli Lan
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, No. 1277 Jiefang Ave, Wuhan, 430022, China.
| | - Quanyong Luo
- Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600# Yishan Road, Shanghai, 200233, China.
| | - Weibo Cai
- Department of Radiology, University of Wisconsin-Madison, Room 7137, 1111 Highland Avenue, Madison, WI, 53705-2275, USA.
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, 53705, USA.
- University of Wisconsin Carbone Cancer Center, Madison, WI, 53705, USA.
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Krishnan HS, Ma L, Vasdev N, Liang SH. 18 F-Labeling of Sensitive Biomolecules for Positron Emission Tomography. Chemistry 2017; 23:15553-15577. [PMID: 28704575 PMCID: PMC5675832 DOI: 10.1002/chem.201701581] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Indexed: 12/21/2022]
Abstract
Positron emission tomography (PET) imaging study of fluorine-18 labeled biomolecules is an emerging and rapidly growing area for preclinical and clinical research. The present review focuses on recent advances in radiochemical methods for incorporating fluorine-18 into biomolecules via "direct" or "indirect" bioconjugation. Recently developed prosthetic groups and pre-targeting strategies, as well as representative examples in 18 F-labeling of biomolecules in PET imaging research studies are highlighted.
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Affiliation(s)
- Hema S. Krishnan
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Longle Ma
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Neil Vasdev
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Steven H. Liang
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
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Schirrmacher R, Wängler B, Bailey J, Bernard-Gauthier V, Schirrmacher E, Wängler C. Small Prosthetic Groups in 18F-Radiochemistry: Useful Auxiliaries for the Design of 18F-PET Tracers. Semin Nucl Med 2017; 47:474-492. [PMID: 28826522 DOI: 10.1053/j.semnuclmed.2017.07.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Prosthetic group (PG) applications in 18F-radiochemistry play a pivotal role among current 18F-labeling techniques for the development and availability of 18F-labeled imaging probes for PET (Wahl, 2002) (1). The introduction and popularization of PGs in the mid-80s by pioneers in 18F-radiochemistry has profoundly changed the landscape of available tracers for PET and has led to a multitude of new imaging agents based on simple and efficiently synthesized PGs. Because of the chemical nature of anionic 18F- (apart from electrophilic low specific activity 18F-fluorine), radiochemistry before the introduction of PGs was limited to simple nucleophilic substitutions of leaving group containing precursor molecules. These precursors were not always available, and some target compounds were either hard to synthesize or not obtainable at all. Even with the advent of recently introduced "late-stage fluorination" techniques for the 18F-fluorination of deactivated aromatic systems, PGs will continue to play a central role in 18F-radiochemistry because of their robust and almost universal usability. The importance of PGs in radiochemistry is shown by its current significance in tracer development and exemplified by an overview of selected methodologies for PG attachment to PET tracer molecules. Especially, click-chemistry approaches to PG conjugation, while furthering the historical evolution of PGs in PET tracer design, play a most influential role in modern PG utilization. All earlier and recent multifaceted approaches in PG development have significantly enriched the contingent of modern 18F-radiochemistry procedures and will continue to do so.
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Affiliation(s)
- Ralf Schirrmacher
- Medical Isotope and Cyclotron Facility, Cross Cancer Institute, University of Alberta, Alberta, Canada.
| | - Björn Wängler
- Molecular Imaging and Radiochemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Germany
| | - Justin Bailey
- Medical Isotope and Cyclotron Facility, Cross Cancer Institute, University of Alberta, Alberta, Canada
| | - Vadim Bernard-Gauthier
- Medical Isotope and Cyclotron Facility, Cross Cancer Institute, University of Alberta, Alberta, Canada
| | - Esther Schirrmacher
- Medical Isotope and Cyclotron Facility, Cross Cancer Institute, University of Alberta, Alberta, Canada
| | - Carmen Wängler
- Biomedical Chemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Germany
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Compounds for radionuclide imaging and therapy of malignant foci characterized by the increased angiogenesis. Russ Chem Bull 2016. [DOI: 10.1007/s11172-016-1309-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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12
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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] [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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Khoshbakht S, Beiki D, Geramifar P, Kobarfard F, Sabzevari O, Amini M, Shahhosseini S. 18FDG-labeled LIKKPF: a PET tracer for apoptosis imaging. J Radioanal Nucl Chem 2016. [DOI: 10.1007/s10967-016-4793-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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14
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Keinänen O, Li XG, Chenna NK, Lumen D, Ott J, Molthoff CFM, Sarparanta M, Helariutta K, Vuorinen T, Windhorst AD, Airaksinen AJ. A New Highly Reactive and Low Lipophilicity Fluorine-18 Labeled Tetrazine Derivative for Pretargeted PET Imaging. ACS Med Chem Lett 2016; 7:62-6. [PMID: 26819667 DOI: 10.1021/acsmedchemlett.5b00330] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 12/10/2015] [Indexed: 12/11/2022] Open
Abstract
A new (18)F-labeled tetrazine derivative was developed aiming at optimal radiochemistry, fast reaction kinetics in inverse electron-demand Diels-Alder cycloaddition (IEDDA), and favorable pharmacokinetics for in vivo bioorthogonal chemistry. The radiolabeling of the tetrazine was achieved in high yield, purity, and specific activity under mild reaction conditions via conjugation with 5-[(18)F]fluoro-5-deoxyribose, providing a glycosylated tetrazine derivative with low lipophilicity. The (18)F-tetrazine showed fast reaction kinetics toward the most commonly used dienophiles in IEDDA reactions. It exhibited excellent chemical and enzymatic stability in mouse plasma and in phosphate-buffered saline (pH 7.41). Biodistribution in mice revealed favorable pharmacokinetics with major elimination via urinary excretion. The results indicate that the glycosylated (18)F-labeled tetrazine is an excellent candidate for in vivo bioorthogonal chemistry applications in pretargeted PET imaging approaches.
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Affiliation(s)
- Outi Keinänen
- Laboratory
of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland
| | - Xiang-Guo Li
- Turku
Positron Emission Tomography (PET) Centre, University of Turku and Turku University Hospital, FI-20521 Turku, Finland
| | - Naveen K. Chenna
- Department
of Forest Products Technology, Aalto University School of Chemical Technology, FI-00076 Espoo, Finland
| | - Dave Lumen
- Laboratory
of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland
| | - Jennifer Ott
- Laboratory
of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland
| | - Carla F. M. Molthoff
- Department
of Radiology and Nuclear Medicine, VU University Medical Center, 1081 HV Amsterdam, The Netherlands
| | - Mirkka Sarparanta
- Laboratory
of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland
- Department
of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Kerttuli Helariutta
- Laboratory
of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland
| | - Tapani Vuorinen
- Department
of Forest Products Technology, Aalto University School of Chemical Technology, FI-00076 Espoo, Finland
| | - Albert D. Windhorst
- Department
of Radiology and Nuclear Medicine, VU University Medical Center, 1081 HV Amsterdam, The Netherlands
| | - Anu J. Airaksinen
- Laboratory
of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland
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15
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Flavell RR, Truillet C, Regan MK, Ganguly T, Blecha JE, Kurhanewicz J, VanBrocklin HF, Keshari KR, Chang CJ, Evans MJ, Wilson DM. Caged [(18)F]FDG Glycosylamines for Imaging Acidic Tumor Microenvironments Using Positron Emission Tomography. Bioconjug Chem 2015; 27:170-8. [PMID: 26649808 DOI: 10.1021/acs.bioconjchem.5b00584] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Solid tumors are hypoxic with altered metabolism, resulting in secretion of acids into the extracellular matrix and lower relative pH, a feature associated with local invasion and metastasis. Therapeutic and diagnostic agents responsive to this microenvironment may improve tumor-specific delivery. Therefore, we pursued a general strategy whereby caged small-molecule drugs or imaging agents liberate their parent compounds in regions of low interstitial pH. In this manuscript, we present a new acid-labile prodrug method based on the glycosylamine linkage, and its application to a class of positron emission tomography (PET) imaging tracers, termed [(18)F]FDG amines. [(18)F]FDG amines operate via a proposed two-step mechanism, in which an acid-labile precursor decomposes to form the common radiotracer 2-deoxy-2-[(18)F]fluoro-d-glucose, which is subsequently accumulated by glucose avid cells. The rate of decomposition of [(18)F]FDG amines is tunable in a systematic fashion, tracking the pKa of the parent amine. In vivo, a 4-phenylbenzylamine [(18)F]FDG amine congener showed greater relative accumulation in tumors over benign tissue, which could be attenuated upon tumor alkalinization using previously validated models, including sodium bicarbonate treatment, or overexpression of carbonic anhydrase. This new class of PET tracer represents a viable approach for imaging acidic interstitial pH with potential for clinical translation.
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Affiliation(s)
- Robert R Flavell
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - Charles Truillet
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - Melanie K Regan
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - Tanushree Ganguly
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - Joseph E Blecha
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - Henry F VanBrocklin
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - Kayvan R Keshari
- Department of Radiology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center , New York, New York 10065, United States
| | - Christopher J Chang
- Departments of Chemistry and Molecular and Cell Biology and the Howard Hughes Medical Institute, University of California , Berkeley, California 94720, United States
| | - Michael J Evans
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
| | - David M Wilson
- Department of Radiology and Biomedical Imaging, University of California , San Francisco, California 94158, United States
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16
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Inkster JAH, Colin DJ, Seimbille Y. A novel 2-cyanobenzothiazole-based (18)F prosthetic group for conjugation to 1,2-aminothiol-bearing targeting vectors. Org Biomol Chem 2015; 13:3667-76. [PMID: 25678209 DOI: 10.1039/c4ob02637c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In a bid to find an efficient means to radiolabel biomolecules under mild conditions for PET imaging, a bifunctional (18)F prosthetic molecule has been developed. The compound, dubbed [(18)F]FPyPEGCBT, consists of a 2-substituted pyridine moiety for [(18)F]F(-) incorporation and a 2-cyanobenzothiazole moiety for coupling to terminal cysteine residues. The two functionalities are separated by a mini-PEG chain. [(18)F]FPyPEGCBT could be prepared from its corresponding 2-trimethylammonium triflate precursor (100 °C, 15 min, MeCN) in preparative yields of 11% ± 2 (decay corrected, n = 3) after HPLC purification. However, because the primary radiochemical impurity of the fluorination reaction will not interact with 1,2-aminothiol functionalities, the (18)F prosthetic could be prepared for bioconjugation reactions by way of partial purification on a molecularly imprinted polymer solid-phase extraction cartridge. [(18)F]FPyPEGCBT was used to (18)F-label a cyclo-(RGDfK) analogue which was modified with a terminal cysteine residue (TCEP·HCl, DIPEA, 30 min, 43 °C, DMF). Final decay-corrected yields of (18)F peptide were 7% ± 1 (n = 9) from end-of-bombardment. This novel integrin-imaging agent is currently being studied in murine models of cancer. We argue that [(18)F]FPyPEGCBT holds significant promise owing to its straightforward preparation, 'click'-like ease of use, and hydrophilic character. Indeed, the water-tolerant radio-bioconjugation protocol reported herein requires only one HPLC step for (18)F peptide purification and can be carried out remotely using a single automated synthesis unit over 124-132 min.
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Affiliation(s)
- James A H Inkster
- University Hospitals of Geneva, Cyclotron Unit, Geneva, Switzerland.
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17
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Abstract
The role of fluorine in drug design and development is expanding rapidly as we learn more about the unique properties associated with this unusual element and how to deploy it with greater sophistication. The judicious introduction of fluorine into a molecule can productively influence conformation, pKa, intrinsic potency, membrane permeability, metabolic pathways, and pharmacokinetic properties. In addition, (18)F has been established as a useful positron emitting isotope for use with in vivo imaging technology that potentially has extensive application in drug discovery and development, often limited only by convenient synthetic accessibility to labeled compounds. The wide ranging applications of fluorine in drug design are providing a strong stimulus for the development of new synthetic methodologies that allow more facile access to a wide range of fluorinated compounds. In this review, we provide an update on the effects of the strategic incorporation of fluorine in drug molecules and applications in positron emission tomography.
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Affiliation(s)
- Eric P Gillis
- Department of Discovery Chemistry, Bristol-Myers Squibb Research and Development , 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Kyle J Eastman
- Department of Discovery Chemistry, Bristol-Myers Squibb Research and Development , 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Matthew D Hill
- Department of Discovery Chemistry, Bristol-Myers Squibb Research and Development , 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - David J Donnelly
- Discovery Chemistry Platforms, PET Radiochemical Synthesis, Bristol-Myers Squibb Research and Development , P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Nicholas A Meanwell
- Department of Discovery Chemistry, Bristol-Myers Squibb Research and Development , 5 Research Parkway, Wallingford, Connecticut 06492, United States
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18
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Khoshbakht S, Kobarfard F, Beiki D, Sabzevari O, Amini M, Mehrnejad F, Tabib K, Shahhosseini S. HYNIC a bifunctional prosthetic group for the labelling of peptides with 99mTc and 18FDG. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-4259-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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19
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Richter S, Wuest M, Bergman CN, Way JD, Krieger S, Rogers BE, Wuest F. Rerouting the metabolic pathway of (18)F-labeled peptides: the influence of prosthetic groups. Bioconjug Chem 2015; 26:201-12. [PMID: 25572982 DOI: 10.1021/bc500599m] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Current translational cancer research is directed to the development of high affinity peptide ligands for targeting neuropeptide receptors overexpressed in different types of cancer. Besides their desired high binding affinity to the receptor, the suitability of radiolabeled peptides as targeting vectors for molecular imaging and therapy depends on additional aspects such as high tumor-to-background ratio, favorable clearance pattern from nontarget tissue, and sufficient metabolic stability in vivo. This study reports how a switch from the prosthetic group, N-succinimidyl-4-[(18)F]fluorobenzoate ([(18)F]SFB), to 2-deoxy-2-[(18)F]fluoro-d-glucose ([(18)F]FDG) effects the metabolic pathway of an (18)F-labeled bombesin derivative, QWAV-Sar-H-FA01010-Tle-NH2. (18)F-Labeled bombesin derivatives represent potent peptide ligands for selective targeting of gastrin-releasing peptide (GRP) receptor-expressing prostate cancer. Radiosynthesis of (18)F-labeled bombesin analogues [(18)F]FBz-Ava-BBN2 and [(18)F]FDG-AOAc-BBN2 was achieved in good radiochemical yields of ~50% at a specific activity exceeding 40 GBq/μmol. Both nonradioactive compounds FBz-Ava-BBN2 and FDG-AOAc-BBN2 inhibited binding of [(125)I]Tyr(4)-bombesin(1-14) in PC3 cells with IC50 values of 9 and 16 nM, respectively, indicating high inhibitory potency. Influence of each prosthetic group was further investigated in PC3 mouse xenografts using dynamic small animal PET imaging. In comparison to [(18)F]FBz-Ava-BBN2, total tumor uptake levels were doubled after injection of [(18)F]FDG-AOAc-BBN2 while renal elimination was increased. Blood clearance and in vivo metabolic stability were similar for both compounds. The switch from [(18)F]SFB to [(18)F]FDG as the prosthetic group led to a significant reduction in lipophilicity which resulted in more favorable renal clearance and increased tumor uptake. The presented single step radiolabeling-glycosylation approach represents an innovative strategy for site-directed peptide labeling with the short-lived positron emitter (18)F while providing a favorable pharmacokinetic profile of (18)F-labeled peptides.
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Affiliation(s)
- Susan Richter
- Department of Oncology, University of Alberta, Cross Cancer Institute , 11560 University Avenue, Edmonton, Alberta T6G 2X4, Canada
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20
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Richter S, Wuest F. 18F-Labeled Peptides: The Future Is Bright. Molecules 2014; 19:20536-20556. [PMID: 25493636 PMCID: PMC6271677 DOI: 10.3390/molecules191220536] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 11/24/2014] [Accepted: 11/28/2014] [Indexed: 01/10/2023] Open
Abstract
Radiolabeled peptides have been the subject of intense research efforts for targeted diagnostic imaging and radiotherapy over the last 20 years. Peptides offer several advantages for receptor imaging and targeted radiotherapy. The low molecular weight of peptides allows for rapid clearance from the blood and non-target tissue, which results in favorable target-to-non-target ratios. Moreover, peptides usually display good tissue penetration and they are generally non-immunogenic. A major drawback is their potential low metabolic stability. The majority of currently used radiolabeled peptides for targeted molecular imaging and therapy of cancer is labeled with various radiometals like 99mTc, 68Ga, and 177Lu. However, over the last decade an increasing number of 18F-labeled peptides have been reported. Despite of obvious advantages of 18F like its ease of production in large quantities at high specific activity, the low β+ energy (0.64 MeV) and the favorable half-life (109.8 min), 18F-labeling of peptides remains a special challenge. The first part of this review will provide a brief overview on chemical strategies for peptide labeling with 18F. A second part will discuss recent technological advances for 18F-labeling of peptides with special focus on microfluidic technology, automation, and kit-like preparation of 18F-labeled peptides.
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Affiliation(s)
- Susan Richter
- Department of Oncology, University of Alberta, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada.
| | - Frank Wuest
- Department of Oncology, University of Alberta, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada.
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21
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Sweetening pharmaceutical radiochemistry by (18)f-fluoroglycosylation: a short review. BIOMED RESEARCH INTERNATIONAL 2014; 2014:214748. [PMID: 24991541 PMCID: PMC4058687 DOI: 10.1155/2014/214748] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 04/15/2014] [Indexed: 12/20/2022]
Abstract
At the time when the highly efficient [(18)F]FDG synthesis was discovered by the use of the effective precursor 1,3,4,6-tetra-O-acetyl-2-O-trifluoromethanesulfonyl- β -D-mannopyranose (mannose triflate) for nucleophilic (18)F-substitution, the field of PET in nuclear medicine experienced a long-term boom. Thirty years later, various strategies for chemoselective (18)F-labeling of biomolecules have been developed, trying to keep up with the emerging field of radiopharmaceutical sciences. Among the new radiochemical strategies, chemoselective (18)F-fluoroglycosylation methods aim at the sweetening of pharmaceutical radiochemistry by providing a powerful and highly valuable tool for the design of (18)F-glycoconjugates with suitable in vivo properties for PET imaging studies. This paper provides a short review (reflecting the literature not older than 8 years) on the different (18)F-fluoroglycosylation reactions that have been applied to the development of various (18)F-glycoconjugate tracers, including not only peptides, but also nonpeptidic tracers and high-molecular-weight proteins.
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22
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Yue X, Yan X, Wu C, Niu G, Ma Y, Jacobson O, Shen B, Kiesewetter DO, Chen X. One-pot two-step radiosynthesis of a new (18)F-labeled thiol reactive prosthetic group and its conjugate for insulinoma imaging. Mol Pharm 2014; 11:3875-84. [PMID: 24798315 PMCID: PMC4224565 DOI: 10.1021/mp5001857] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
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N-(2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethyl)-6-fluoronicotinamide ([18F]FNEM),
a novel prosthetic agent that is thiol-specific, was synthesized using
a one-pot two-step strategy: (1) 18F incorporation by a
nucleophilic displacement of trimethylammonium substrate under mild
conditions; (2) amidation of the resulting 6-[18F]fluoronicotinic
acid 2,3,5,6-tetrafluorophenyl ester with N-(2-aminoethyl)maleimide
trifluoroacetate salt. The radiosynthesis of the maleimide tracer
was completed in 75 min from [18F]fluoride with 26 ±
5% decay uncorrected radiochemical yield, and specific activity of
19–88 GBq/μmol (decay uncorrected). The in vitro cell uptake, in vivo biodistribution, and positron
emission tomography (PET) imaging properties of its conjugation product
with [Cys40]-exendin-4 were described. [18F]FNEM-Cys40-exendin-4 showed specific targeting of glucagon-like peptide
1 receptor (GLP-1R) positive insulinomas and comparable imaging results
to our recently reported [18F]FPenM-Cys40-exendin-4.
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Affiliation(s)
- Xuyi Yue
- National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , 35A Convent Drive, Bethesda, Maryland 20892, United States
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23
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Simeček J, Notni J, Kapp TG, Kessler H, Wester HJ. Benefits of NOPO as chelator in gallium-68 peptides, exemplified by preclinical characterization of (68)Ga-NOPO-c(RGDfK). Mol Pharm 2014; 11:1687-95. [PMID: 24669840 DOI: 10.1021/mp5000746] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The αvβ3-integrin addressing cyclic pentapeptide cyclo(RGDfK) was conjugated to NOPO, 1,4,7-triazacyclononane-1,4-bis[methylene(hydroxymethyl)phosphinic acid]-7-[methylene(2-carboxyethyl)phosphinic acid], a bifunctional chelator with exceptional gallium-68 labeling properties. NOPO-c(RGDfK) and its Ga(III) and Cu(II) complexes showed high affinity to αvβ3 integrin (IC50 = 0.94 ± 0.06, 1.02 ± 0.09, and 0.51 ± 0.06 nM, respectively). (68)Ga labeling of NOPO-c(RGDfK) in an automated GMP-compliant procedure was performed with near-quantitative radiochemical yield, using precursor amounts as low as 0.5 nmol (approximately 0.6 μg). (68)Ga-NOPO-c(RGDfK) was obtained with high purity (>99% by radio-HPLC/TLC) and, optionally, could be produced with specific activities up to 6 TBq/μmol. M21/M21L (human melanoma with high/low αvβ3 integrin expression) xenografted athymic CD-1 nude mice were used for biodistribution, in vivo stability studies, and PET imaging. (68)Ga-NOPO-c(RGDfK) showed rapid and specific uptake in M21 tumor xenografts (2.02 ± 0.34% ID/g at 60 min p.i.) and was found stable in vivo. Its high hydrophilicity is reflected by an octanol-water distribution coefficient (log D = -4.6) which is more than 1 order of magnitude lower compared to respective NOTA or DOTA analogues. As expected, (68)Ga-NOPO-c(RGDfK) thus showed fast renal clearance from nontargeted tissues. We conclude that NOPO might generally prove a useful means to improve renal clearance of corresponding radiopharmaceuticals by increasing the polarity of its bioconjugates. Favorable labeling properties render NOPO conjugates highly recommendable for reliable routine production of (68)Ga-radiopharmaceuticals in a clinical setting.
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Affiliation(s)
- Jakub Simeček
- Pharmaceutical Radiochemistry and ‡Institute for Advanced Study and Center of Integrated Protein Science, Technische Universität München , München, Germany
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24
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Laverman P, McBride WJ, Sharkey RM, Goldenberg DM, Boerman OC. Al18F labeling of peptides and proteins. J Labelled Comp Radiopharm 2014; 57:219-23. [DOI: 10.1002/jlcr.3161] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/29/2013] [Indexed: 12/29/2022]
Affiliation(s)
- Peter Laverman
- Department of Nuclear Medicine; Radboud University Medical Center; Nijmegen The Netherlands
| | | | | | | | - Otto C. Boerman
- Department of Nuclear Medicine; Radboud University Medical Center; Nijmegen The Netherlands
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25
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Using 5-deoxy-5-[18F]fluororibose to glycosylate peptides for positron emission tomography. Nat Protoc 2013; 9:138-45. [PMID: 24356772 DOI: 10.1038/nprot.2013.170] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
So far seven peptide-based (18)F-radiopharmaceuticals for diagnostic applications with positron emission tomography (PET) have entered into clinical trials. Three candidates out of these seven are glycosylated peptides, which may be explained by the beneficial influence of glycosylation on in vivo pharmacokinetics of peptide tracers. This protocol describes the method for labeling peptides with 5-deoxy-5-[(18)F]fluororibose ([(18)F]FDR) as a prosthetic group. The synthesis of [(18)F]FDR is effected by a nucleophilic fluorination step by using dried Kryptofix 2.2.2-K2CO3-K(18)F complex and a subsequent HCl-catalyzed hydrolysis. The conjugation of [(18)F]FDR to the N-terminus aminooxy (-ONH2)-functionalized peptides is carried out in anilinium buffer at pH 4.6 and at room temperature (RT, 21-23 °C), with the concentration of peptide precursors being 0.3 mM. The procedure takes about 120 min and includes two cartridge isolation steps and two reversed-phase (RP) HPLC purification steps. The quaternary methyl amine (QMA) anion exchange cartridge and the hydrophilic-lipophilic balanced (HLB) cartridge are used for the isolation of (18)F-fluoride and [(18)F]FDR-conjugated peptides, respectively. The first HPLC purification provides the (18)F-fluorinated precursor of [(18)F]FDR and the second HPLC purification is to separate labeled peptides from their unlabeled precursors. The final product is formulated in PBS ready for injection, with a radiochemical purity of >98% and a radiochemical yield (RCY) of 27-37% starting from the end of bombardment (EOB). The carbohydrate nature of [(18)F]FDR and the operational convenience of this protocol should facilitate its general use.
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26
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Maschauer S, Haubner R, Kuwert T, Prante O. 18F-Glyco-RGD Peptides for PET Imaging of Integrin Expression: Efficient Radiosynthesis by Click Chemistry and Modulation of Biodistribution by Glycosylation. Mol Pharm 2013; 11:505-15. [DOI: 10.1021/mp4004817] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Simone Maschauer
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University, 91054 Erlangen, Germany
| | - Roland Haubner
- Department
of Nuclear Medicine, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Torsten Kuwert
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University, 91054 Erlangen, Germany
| | - Olaf Prante
- Department
of Nuclear Medicine, Molecular Imaging and Radiochemistry, Friedrich Alexander University, 91054 Erlangen, Germany
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27
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Bouvet VR, Wuest F. Application of [18F]FDG in radiolabeling reactions using microfluidic technology. LAB ON A CHIP 2013; 13:4290-4294. [PMID: 24056916 DOI: 10.1039/c3lc50797a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Radiolabeling of peptides with the short-lived positron emitter fluorine-18 is usually a challenging endeavour. Conventional radiolabeling reactions mostly require fairly large amounts of peptides as labeling precursors, and extensive synthesis times. Intrinsic advantages of microfluidic technology permit to overcome these hurdles. Herein, we describe how microfluidic technology combined with [(18)F]FDG as readily available PET radiotracer allows for fast and high yielding radiolabeling reactions of peptides with fluorine-18.
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Affiliation(s)
- Vincent R Bouvet
- Department of Oncology, University of Alberta, Edmonton, AB, Canada.
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28
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Flook AM, Yang J, Miao Y. Effects of amino acids on melanoma targeting and clearance properties of Tc-99m-labeled Arg-X-Asp-conjugated α-melanocyte stimulating hormone peptides. J Med Chem 2013; 56:8793-802. [PMID: 24131154 DOI: 10.1021/jm4012356] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The purpose of this study was to examine the effects of amino acids on melanoma targeting and clearance properties of new (99m)Tc-labeled Arg-X-Asp-conjugated α-melanocyte stimulating hormone (α-MSH) peptides. RSD-Lys-(Arg(11))CCMSH {c[Arg-Ser-Asp-DTyr-Asp]-Lys-Cys-Cys-Glu-His-dPhe-Arg-Trp-Cys-Arg-Pro-Val-NH2}, RNleD-Lys-(Arg(11))CCMSH, RPheD-Lys-(Arg(11))CCMSH, and RdPheD-Lys-(Arg(11))CCMSH peptides were synthesized and evaluated for their melanocortin-1 (MC1) receptor binding affinities in B16/F1 melanoma cells. The biodistribution of (99m)Tc-RSD-Lys-(Arg(11))CCMSH, (99m)Tc-RFD-Lys-(Arg(11))CCMSH, and (99m)Tc-RfD-Lys-(Arg(11))CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The substitution of Gly with Ser, Phe, and dPhe increased the MC1 receptor binding affinities of the peptides, whereas the substitution of Gly with Nle decreased the MC1 receptor binding affinity of the peptide. (99m)Tc-RSD-Lys-(Arg(11))CCMSH exhibited the highest melanoma uptake (18.01 ± 4.22% ID/g) and the lowest kidney and liver uptake among these (99m)Tc-peptides. The B16/F1 melanoma lesions could be clearly visualized by SPECT/CT using (99m)Tc-RSD-Lys-(Arg(11))CCMSH as an imaging probe. It is desirable to reduce the renal uptake of (99m)Tc-RSD-Lys-(Arg(11))CCMSH to facilitate its potential therapeutic application.
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Affiliation(s)
- Adam M Flook
- College of Pharmacy, ‡Cancer Research and Treatment Center, §Department of Dermatology, University of New Mexico , Albuquerque, New Mexico, 87131, United States
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29
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Dijkgraaf I, Terry SYA, McBride WJ, Goldenberg DM, Laverman P, Franssen GM, Oyen WJG, Boerman OC. Imaging integrin alpha-v-beta-3 expression in tumors with an 18F-labeled dimeric RGD peptide. CONTRAST MEDIA & MOLECULAR IMAGING 2013; 8:238-45. [PMID: 23606427 DOI: 10.1002/cmmi.1523] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 10/19/2012] [Accepted: 11/19/2012] [Indexed: 01/26/2023]
Abstract
Integrin αv β3 receptors are expressed on activated endothelial cells during neovascularization to maintain tumor growth. Many radiolabeled probes utilize the tight and specific association between the arginine-glycine-aspartatic acid (RGD) peptide and integrin αv β3 , but one main obstacle for any clinical application of these probes is the laborious multistep radiosynthesis of (18)F. In this study, the dimeric RGD peptide, E-[c(RGDfK)]2, was conjugated with NODAGA and radiolabeled with (18)F in a simple one-pot process with a radiolabeling yield of 20%, the whole process lasting only 45 min. NODAGA-E-[c(RGDfK)]2 labeled with (18)F at a specific activity of 1.8 MBq nmol(-1) and a radiochemical purity of 100% could be achieved. The logP value of (18)F-labeled NODAGA-E-[c(RGDfK)]2 was -4.26 ± 0.02. In biodistribution studies, (18)F-NODAGA-E-[c(RGDfK)]2 cleared rapidly from the blood with 0.03 ± 0.01 percentage injected dose per gram (%ID g(-1)) in the blood at 2 h p.i., mainly via the kidneys, and showed good in vivo stability. Tumor uptake of (18)F-NODAGA-E-[c(RGDfK)]2 (3.44 ± 0.20 %ID g(-1), 2 h p.i.) was significantly lower than that of reference compounds (68) Ga-labeled NODAGA-E-[c(RGDfK)]2 (6.26 ± 0.76 %ID g(-1) ; p <0.001) and (111) In-labeled NODAGA-E-[c(RGDfK)]2 (4.99 ± 0.64 %ID g(-1) ; p < 0.01). Co-injection of an excess of unlabeled NODAGA-E-[c(RGDfK)]2 along with (18)F-NODAGA-E-[c(RGDfK)]2 resulted in significantly reduced radioactivity concentrations in the tumor (0.85 ± 0.13 %ID g(-1)). The αv β3 integrin-expressing SK-RC-52 tumor could be successfully visualized by microPET with (18)F-labeled NODAGA-E-[c(RGDfK)]2 . In conclusion, NODAGA-E-[c(RGDfK)]2 could be labeled rapidly with (18)F using a direct aqueous, one-pot method and it accumulated specifically in αv β3 integrin-expressing SK-RC-52 tumors, allowing for visualization by microPET.
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Affiliation(s)
- Ingrid Dijkgraaf
- Department of Biochemistry, Cardiovascular Research Institute, Maastricht University, Maastricht, The Netherlands
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Flook AM, Yang J, Miao Y. Evaluation of new Tc-99m-labeled Arg-X-Asp-conjugated α-melanocyte stimulating hormone peptides for melanoma imaging. Mol Pharm 2013; 10:3417-24. [PMID: 23885640 DOI: 10.1021/mp400248f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The purpose of this study was to examine the melanoma targeting and imaging properties of two new (99m)Tc-labeled Arg-X-Asp-conjugated α-melanocyte stimulating hormone (α-MSH) peptides. RTD-Lys-(Arg(11))CCMSH {c[Asp-Arg-Thr-Asp-DTyr]-Lys-Cys-Cys-Glu-His-DPhe-Arg-Trp-Cys-Arg-Pro-Val-NH2} and RVD-Lys-(Arg(11))CCMSH peptides were synthesized, and their melanocortin-1 (MC1) receptor binding affinities were determined in B16/F1 melanoma cells. The biodistribution and melanoma imaging properties of (99m)Tc-RTD-Lys-(Arg(11))CCMSH and (99m)Tc-RVD-Lys-(Arg(11))CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The IC50 values of RTD-Lys-(Arg(11))CCMSH and RVD-Lys-(Arg(11))CCMSH were 0.7 ± 0.07 and 1.0 ± 0.3 nM in B16/F1 melanoma cells. Both (99m)Tc-RTD-Lys-(Arg(11))CCMSH and (99m)Tc-RVD-Lys-(Arg(11))CCMSH displayed high melanoma uptake. (99m)Tc-RTD-Lys-(Arg(11))CCMSH exhibited the highest tumor uptake of 18.77 ± 5.13% ID/g at 2 h postinjection, whereas (99m)Tc-RVD-Lys-(Arg(11))CCMSH reached the highest tumor uptake of 19.63 ± 4.68% ID/g at 4 h postinjection. Both (99m)Tc-RTD-Lys-(Arg(11))CCMSH and (99m)Tc-RVD-Lys-(Arg(11))CCMSH showed low accumulation in normal organs (<1.7% ID/g) except for the kidneys at 2 h postinjection. The renal uptake of (99m)Tc-RTD-Lys-(Arg(11))CCMSH and (99m)Tc-RVD-Lys-(Arg(11))CCMSH was 135.14 ± 23.62 and 94.01 ± 18.31% ID/g at 2 h postinjection, respectively. The melanoma lesions were clearly visualized by single-photon emission computed tomography (SPECT)/CT using either (99m)Tc-RTD-Lys-(Arg(11))CCMSH or (99m)Tc-RVD-Lys-(Arg(11))CCMSH as an imaging probe at 2 h postinjection. Overall, the introduction of Thr or Val residue retained high melanoma uptake of (99m)Tc-RTD-Lys-(Arg(11))CCMSH and (99m)Tc-RVD-Lys-(Arg(11))CCMSH. However, high renal uptake of (99m)Tc-RTD-Lys-(Arg(11))CCMSH and (99m)Tc-RVD-Lys-(Arg(11))CCMSH need to be reduced to facilitate their future applications.
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Affiliation(s)
- Adam M Flook
- College of Pharmacy, ‡Cancer Research and Treatment Center, and §Department of Dermatology, University of New Mexico , Albuquerque, New Mexico 87131, United States
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Li XG, Autio A, Ahtinen H, Helariutta K, Liljenbäck H, Jalkanen S, Roivainen A, Airaksinen AJ. Translating the concept of peptide labeling with 5-deoxy-5-[18F]fluororibose into preclinical practice: 18F-labeling of Siglec-9 peptide for PET imaging of inflammation. Chem Commun (Camb) 2013; 49:3682-3684. [PMID: 23536117 DOI: 10.1039/c3cc40738a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Peptide glycosylation with 5-deoxy-5-[(18)F]fluororibose was translated into preclinical settings. The novel (18)F-labeled Siglec-9 peptide was produced using an automated synthesis procedure. The (18)F-labeled Siglec-9 peptide showed favorable binding in the animal model of inflammation in vivo.
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Affiliation(s)
- Xiang-Guo Li
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, FI-20014 Turku, Finland. and Turku PET Centre, University of Turku and Turku University Hospital, FI-20521 Turku, Finland.
| | - Anu Autio
- Turku PET Centre, University of Turku and Turku University Hospital, FI-20521 Turku, Finland.
| | - Helena Ahtinen
- Turku PET Centre, University of Turku and Turku University Hospital, FI-20521 Turku, Finland.
| | - Kerttuli Helariutta
- Laboratory of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland.
| | - Heidi Liljenbäck
- Turku PET Centre, University of Turku and Turku University Hospital, FI-20521 Turku, Finland. and Turku Center for Disease Modeling, University of Turku, FI-20014 Turku, Finland
| | - Sirpa Jalkanen
- MediCity Research Laboratory and Department of Medical Microbiology and Immunology, University of Turku, FI-20014 Turku, Finland
| | - Anne Roivainen
- Turku PET Centre, University of Turku and Turku University Hospital, FI-20521 Turku, Finland. and Turku Center for Disease Modeling, University of Turku, FI-20014 Turku, Finland
| | - Anu J Airaksinen
- Laboratory of Radiochemistry, Department of Chemistry, University of Helsinki, FI-00014 Helsinki, Finland.
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Cai H, Conti PS. RGD-based PET tracers for imaging receptor integrin αv β3 expression. J Labelled Comp Radiopharm 2013; 56:264-79. [PMID: 24285371 DOI: 10.1002/jlcr.2999] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 11/02/2012] [Accepted: 11/06/2012] [Indexed: 12/20/2022]
Abstract
Positron emission tomography (PET) imaging of receptor integrin αv β3 expression may play a key role in the early detection of cancer and cardiovascular diseases, monitoring disease progression, evaluating therapeutic response, and aiding anti-angiogenic drugs discovery and development. The last decade has seen the development of new PET tracers for in vivo imaging of integrin αv β3 expression along with advances in PET chemistry. In this review, we will focus on the radiochemistry development of PET tracers based on arginine-glycine-aspartic acid (RGD) peptide, present an overview of general strategies for preparing RGD-based PET tracers, and review the recent advances in preparations of (18) F-labeled, (64) Cu-labeled, and (68) Ga-labeled RGD tracers, RGD-based PET multivalent probes, and RGD-based PET multimodality probes for imaging receptor integrin αv β3 expression.
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Affiliation(s)
- Hancheng Cai
- PET Center, Children's Hospital of Michigan, Detroit Medical Center, Detroit, MI, 48201, USA; Wayne State University School of Medicine, Detroit, MI, 48201, USA
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33
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Ribeiro Morais G, Falconer RA, Santos I. Carbohydrate-Based Molecules for Molecular Imaging in Nuclear Medicine. European J Org Chem 2013. [DOI: 10.1002/ejoc.201201457] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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34
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Dall'Angelo S, Zhang Q, Fleming IN, Piras M, Schweiger LF, O'Hagan D, Zanda M. Efficient bioconjugation of 5-fluoro-5-deoxy-ribose (FDR) to RGD peptides for positron emission tomography (PET) imaging of αvβ3 integrin receptor. Org Biomol Chem 2013; 11:4551-8. [DOI: 10.1039/c3ob40550h] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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35
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Li XG, Haaparanta M, Solin O. Oxime formation for fluorine-18 labeling of peptides and proteins for positron emission tomography (PET) imaging: A review. J Fluor Chem 2012. [DOI: 10.1016/j.jfluchem.2012.07.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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36
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Fani M, Maecke HR. Radiopharmaceutical development of radiolabelled peptides. Eur J Nucl Med Mol Imaging 2012; 39 Suppl 1:S11-30. [PMID: 22388624 DOI: 10.1007/s00259-011-2001-z] [Citation(s) in RCA: 155] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Receptor targeting with radiolabelled peptides has become very important in nuclear medicine and oncology in the past few years. The overexpression of many peptide receptors in numerous cancers, compared to their relatively low density in physiological organs, represents the molecular basis for in vivo imaging and targeted radionuclide therapy with radiolabelled peptide-based probes. The prototypes are analogs of somatostatin which are routinely used in the clinic. More recent developments include somatostatin analogs with a broader receptor subtype profile or with antagonistic properties. Many other peptide families such as bombesin, cholecystokinin/gastrin, glucagon-like peptide-1 (GLP-1)/exendin, arginine-glycine-aspartic acid (RGD) etc. have been explored during the last few years and quite a number of potential radiolabelled probes have been derived from them. On the other hand, a variety of strategies and optimized protocols for efficient labelling of peptides with clinically relevant radionuclides such as (99m)Tc, M(3+) radiometals ((111)In, (86/90)Y, (177)Lu, (67/68)Ga), (64/67)Cu, (18)F or radioisotopes of iodine have been developed. The labelling approaches include direct labelling, the use of bifunctional chelators or prosthetic groups. The choice of the labelling approach is driven by the nature and the chemical properties of the radionuclide. Additionally, chemical strategies, including modification of the amino acid sequence and introduction of linkers/spacers with different characteristics, have been explored for the improvement of the overall performance of the radiopeptides, e.g. metabolic stability and pharmacokinetics. Herein, we discuss the development of peptides as radiopharmaceuticals starting from the choice of the labelling method and the conditions to the design and optimization of the peptide probe, as well as some recent developments, focusing on a selected list of peptide families, including somatostatin, bombesin, cholecystokinin/gastrin, GLP-1/exendin and RGD.
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Affiliation(s)
- Melpomeni Fani
- Department of Nuclear Medicine, University Hospital Freiburg, Hugstetterstrasse 55, 79106 Freiburg, Germany.
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37
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Smith TAD. [18F]Fluoride labelling of macromolecules in aqueous conditions: silicon and boroaryl-based [18F]fluorine acceptors, [18F]FDG conjugation and Al18F chelation. J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.2940] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Tim A. D. Smith
- Biomedical Physics Building, Division of Applied Medicine; University of Aberdeen; Foresterhill; Aberdeen; AB; 25 2TN, 01224 553481; UK
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Li XG, Dall'Angelo S, Schweiger LF, Zanda M, O'Hagan D. [18F]-5-Fluoro-5-deoxyribose, an efficient peptide bioconjugation ligand for positron emission tomography (PET) imaging. Chem Commun (Camb) 2012; 48:5247-9. [PMID: 22476360 DOI: 10.1039/c2cc31262j] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
[(18)F]-5-Fluoro-5-deoxyribose ([(18)F]-FDR) conjugates much more rapidly than [(18)F]-FDG under mild reaction conditions to peptides and offers new prospects for mild and rapid bioconjugation for fluorine-18 labelling in PET imaging.
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Affiliation(s)
- Xiang-Guo Li
- University of St Andrews, School of Chemistry and Centre for Biomolecular Science, North Haugh, St Andrews, Fife KY16 9ST, UK.
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39
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Yang J, Miao Y. Substitution of Gly with Ala enhanced the melanoma uptake of technetium-99m-labeled Arg-Ala-Asp-conjugated alpha-melanocyte stimulating hormone peptide. Bioorg Med Chem Lett 2012; 22:1541-5. [PMID: 22297112 DOI: 10.1016/j.bmcl.2012.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 01/03/2012] [Accepted: 01/03/2012] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to determine the melanoma targeting property of (99m)Tc-RAD-Lys-(Arg(11))CCMSH in B16/F1 melanoma-bearing C57 mice and compare with (99m)Tc-RGD-Lys-(Arg(11))CCMSH we previously reported. (99m)Tc-RAD-Lys-(Arg(11))CCMSH exhibited rapid and high tumor uptake (19.91±4.02% ID/g at 2h post-injection) in B16/F1 melanoma-bearing C57 mice. The tumor uptake of (99m)Tc-RAD-Lys-(Arg(11))CCMSH was 1.51, 1.34 and 1.43 times the tumor uptake of (99m)Tc-RGD-Lys-(Arg(11))CCMSH at 0.5, 2 and 4h post-injection, respectively. Flank B16/F1 melanoma lesions were clearly imaged at 2h post-injection using (99m)Tc-RAD-Lys-(Arg(11))CCMSH as an imaging probe. The substitution of Gly with Ala significantly enhanced the melanoma uptake of (99m)Tc-RAD-Lys-(Arg(11))CCMSH compared to (99m)Tc-RGD-Lys-(Arg(11))CCMSH in B16/F1 melanoma-bearing C57 mice, providing a new insight into the design of α-MSH peptides for melanoma targeting.
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Affiliation(s)
- Jianquan Yang
- College of Pharmacy, University of New Mexico, Albuquerque, NM 87131, USA
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40
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Optimized labeling of NOTA-conjugated octreotide with F-18. Tumour Biol 2011; 33:427-34. [PMID: 22009690 PMCID: PMC3296034 DOI: 10.1007/s13277-011-0250-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 10/05/2011] [Indexed: 11/22/2022] Open
Abstract
We recently reported a facile method based on the chelation of [18F]aluminum fluoride (Al18F) by NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid). Here, we present a further optimization of the 18F labeling of NOTA-octreotide (IMP466). Octreotide was conjugated with the NOTA chelate and was labeled with 18F in a two-step, one-pot method. The labeling procedure was optimized with regard to the labeling buffer, ionic strength, peptide concentration, and temperature. Radiochemical yield, specific activity, in vitro stability, and receptor affinity were determined. Biodistribution of 18F-IMP466 was studied in AR42J tumor-bearing mice. In addition, microPET/CT images were acquired. IMP466 was labeled with Al18F in a single step with 97% yield in the presence of 80% (v/v) acetonitrile or ethanol. The labeled product was purified by HPLC to remove unlabeled peptide and unbound Al18F. The radiolabeling, including purification, was performed for 45 min. Specific activities of 48,000 GBq/mmol could be obtained. 18F-IMP466 showed a high tumor uptake and excellent tumor-to-blood ratios at 2 h post-injection. In addition, the low bone uptake indicated that the Al18F–NOTA complex was stable in vivo. PET/CT scans revealed excellent tumor delineation and specific accumulation in the tumor. Uptake in receptor-negative organs was low. NOTA-octreotide could be labeled with 18F in quantitative yields using a rapid two-step, one-pot, method. The compound was stable in vivo and showed rapid accretion in SSTR2-receptor-expressing AR42J tumors in nude mice. This method can be used to label other NOTA-conjugated compounds such as RGD peptides, GRPR-binding peptides, and Affibody molecules with 18F.
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41
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Carberry P, Carpenter AP, Kung HF. Fluoride-18 radiolabeling of peptides bearing an aminooxy functional group to a prosthetic ligand via an oxime bond. Bioorg Med Chem Lett 2011; 21:6992-5. [PMID: 22024031 DOI: 10.1016/j.bmcl.2011.09.124] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 09/26/2011] [Accepted: 09/28/2011] [Indexed: 11/27/2022]
Abstract
We have developed a novel F-18 prosthetic ligand named fluoro-PEG-benzaldehyde (FPBA) 1. [(18)F]-FPBA 1 is formed in situ from its radiolabeled precursor [(18)F]6. Compound 6 is efficiently synthesized in four steps starting from commercially available 6-bromo-3-pyridine carbaldehyde 2. [(18)F]-FPBA was evaluated as a prosthetic ligand to radiolabel three cyclic peptides bearing an aminooxy functional group at the N-terminus position. Acetal [(18)F]6 is purified by either solid-phase extraction (SPE) or reverse-phase HPLC with the overall radiochemical yields (RCY) and radiochemical purity (RCP) in very close agreement. The SPE purification process has the advantage of shorter reaction times (71-87 min for entire reaction sequence), while the use of the reverse-phase HPLC purification process allows the use of up to fifty times less of the expensive synthetic peptides (~ 50 nmol) in the oxime coupling reaction. We have demonstrated an efficient methodology in the production of [(18)F]-FPBA 1 and demonstrated its use as a prosthetic ligand for the labeling of peptides possessing an aminooxy functional group.
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Affiliation(s)
- Patrick Carberry
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
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Carberry P, Lieberman BP, Ploessl K, Choi SR, Haase DN, Kung HF. New F-18 prosthetic group via oxime coupling. Bioconjug Chem 2011; 22:642-53. [PMID: 21452846 DOI: 10.1021/bc1004262] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A novel fluorine-18 prosthetic ligand, 5-(1,3-dioxolan-2-yl)-2-(2-(2-(2-fluoroethoxy)ethoxy)ethoxy)pyridine [(18)F]2, has been synthesized. The prosthetic ligand is formed in high radiochemical yield (rcy = 71 ± 2%, n = 3) with excellent radiochemical purity (rcp = 99 ± 1%, n = 3) in a short reaction time (10 min). [(18)F]2 is a small, neutral, organic complex, easily synthesized in four steps from a readily available starting material. It can be anchored onto a target molecule containing an aminooxy functional group under acidic conditions by way of an oxime bond. We report herein two examples [(18)F]23 and [(18)F]24, potential imaging agents for β-amyloid plaques, which were labeled with this prosthetic group. This approach could be used for labeling proteins and peptides containing an aminooxy group. Biodistribution in male ICR mice for both oxime labeled complexes [(18)F]23 and [(18)F]24 were compared to that of the known β-amyloid plaque indicator, [(18)F]-AV-45, florbetapir 1. Oximes [(18)F]23 and [(18)F]24 are larger in size and therefore should reduce the blood-brain barrier (BBB) penetration. The brain uptake for oxime [(18)F]23 appeared to be reduced, but still retained some capability to cross the BBB. Oxime [(18)F]24 showed promising results after 2 min post injection (0.48% dose/gram); however, the uptake increased after 30 min post injection (0.92% dose/gram) suggesting an in vivo decomposition/metabolism of compound [(18)F]24. We have demonstrated a general protocol for the fluoride-18 labeling with a new prosthetic ligand [(18)F]2 that is tolerant toward several functional groups and is formed via chemoselective oxime coupling.
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Affiliation(s)
- Patrick Carberry
- Department of Radiology, University of Pennsylvania , 3700 Market Street, Room 305, Philadelphia, Pennsylvania 19104, United States
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Simpson M, Trembleau L, Cheyne RW, Smith TA. One-pot production of 18F-biotin by conjugation with 18F-FDG for pre-targeted imaging: Synthesis and radio-labelling of a PEGylated precursor. Appl Radiat Isot 2011; 69:418-22. [DOI: 10.1016/j.apradiso.2010.10.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 10/12/2010] [Accepted: 10/17/2010] [Indexed: 11/15/2022]
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Haubner R, Beer AJ, Wang H, Chen X. Positron emission tomography tracers for imaging angiogenesis. Eur J Nucl Med Mol Imaging 2010; 37 Suppl 1:S86-103. [PMID: 20559632 PMCID: PMC3629959 DOI: 10.1007/s00259-010-1503-4] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Position emission tomography imaging of angiogenesis may provide non-invasive insights into the corresponding molecular processes and may be applied for individualized treatment planning of antiangiogenic therapies. At the moment, most strategies are focusing on the development of radiolabelled proteins and antibody formats targeting VEGF and its receptor or the ED-B domain of a fibronectin isoform as well as radiolabelled matrix metalloproteinase inhibitors or alpha(v)beta(3) integrin antagonists. Great efforts are being made to develop suitable tracers for different target structures. All of the major strategies focusing on the development of radiolabelled compounds for use with positron emission tomography are summarized in this review. However, because the most intensive work is concentrated on the development of radiolabelled RGD peptides for imaging alpha(v)beta(3) expression, which has successfully made its way from bench to bedside, these developments are especially emphasized.
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Affiliation(s)
- Roland Haubner
- Department of Nuclear Medicine, Medical University Innsbruck, Austria.
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Yang J, Guo H, Miao Y. Technetium-99m-labeled Arg-Gly-Asp-conjugated alpha-melanocyte stimulating hormone hybrid peptides for human melanoma imaging. Nucl Med Biol 2010; 37:873-83. [PMID: 21055617 DOI: 10.1016/j.nucmedbio.2010.05.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 05/07/2010] [Accepted: 05/17/2010] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The purpose of this study was to examine whether (99m)Tc-labeled Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone (α-MSH) hybrid peptide targeting both melanocortin-1 (MC1) and α(v)β(3) integrin receptors was superior in melanoma targeting to (99m)Tc-labeled α-MSH or RGD peptide targeting only the MC1 or α(v)β(3) integrin receptor. METHODS RGD-Lys-(Arg(11))CCMSH, RAD-Lys-(Arg(11))CCMSH and RGD-Lys-(Arg(11))CCMSHscramble were designed to target both MC1 and α(v)β(3) integrin receptors, MC1 receptor only and α(v)β(3) integrin receptor only, respectively. The MC1 or α(v)β(3) integrin receptor binding affinities of three peptides were determined in M21 human melanoma cells. The melanoma targeting properties of (99m)Tc-labeled RGD-Lys-(Arg(11))CCMSH, RAD-Lys-(Arg(11))CCMSH and RGD-Lys-(Arg(11))CCMSHscramble were determined in M21 human melanoma-xenografted nude mice. Meanwhile, the melanoma uptake of (99m)Tc-RGD-Lys-(Arg(11))CCMSH was blocked with various non-radiolabeled peptides in M21 melanoma xenografts. RESULTS RGD-Lys-(Arg(11))CCMSH displayed 2.0 and 403 nM binding affinities to both MC1 and α(v)β(3) integrin receptors, whereas RAD-Lys-(Arg(11))CCMSH or RGD-Lys-(Arg(11))CCMSHscramble lost their α(v)β(3) integrin receptor binding affinity by greater than 248-fold or MC1 receptor binding affinity by more than 100-fold, respectively. The melanoma uptake of (99m)Tc-RGD-Lys-(Arg(11))CCMSH was 2.49 and 2.24 times (P < .05) the melanoma uptakes of (99m)Tc-RAD-Lys-(Arg(11))CCMSH and (99m)Tc-RGD-Lys-(Arg(11))CCMSHscramble at 2 h post-injection, respectively. Either RGD or (Arg(11))CCMSH peptide co-injection could block 42% and 57% of the tumor uptake of (99m)Tc-RGD-Lys-(Arg(11))CCMSH, whereas the coinjection of RGD+(Arg(11))CCMSH peptide mixture could block 66% of the tumor uptake of (99m)Tc-RGD-Lys-(Arg(11))CCMSH. CONCLUSIONS Targeting both MC1 and α(v)β(3) integrin receptors enhanced the melanoma uptake of (99m)Tc-RGD-Lys-(Arg(11))CCMSH in M21 human melanoma xenografts. Flank M21 human melanoma tumors were clearly visualized by single photon emission computed tomography/computed tomographic imaging using (99m)Tc-RGD-Lys-(Arg(11))CCMSH as an imaging probe, highlighting its potential use as a dual-receptor-targeting imaging probe for human melanoma detection.
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Affiliation(s)
- Jianquan Yang
- College of Pharmacy, University of New Mexico, Albuquerque, NM 87131, USA
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Laverman P, McBride WJ, Sharkey RM, Eek A, Joosten L, Oyen WJG, Goldenberg DM, Boerman OC. A novel facile method of labeling octreotide with (18)F-fluorine. J Nucl Med 2010; 51:454-61. [PMID: 20150268 DOI: 10.2967/jnumed.109.066902] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Several methods have been developed to label peptides with (18)F. However, in general these are laborious and require a multistep synthesis. We present a facile method based on the chelation of (18)F-aluminum fluoride (Al(18)F) by 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA). The method is characterized by the labeling of NOTA-octreotide (NOTA-d-Phe-cyclo[Cys-Phe-d-Trp-Lys-Thr-Cys]-Throl (MH(+) 1305) [IMP466]) with (18)F. METHODS Octreotide was conjugated with the NOTA chelate and labeled with (18)F in a 2-step, 1-pot method. The labeling procedure was optimized with regard to the labeling buffer, peptide, and aluminum concentration. Radiochemical yield, specific activity, in vitro stability, and receptor affinity were determined. Biodistribution of (18)F-IMP466 was studied in AR42J tumor-bearing mice and compared with that of (68)Ga-labeled IMP466. In addition, small-animal PET/CT images were acquired. RESULTS IMP466 was labeled with Al(18)F in a single step with 50% yield. The labeled product was purified by high-performance liquid chromatography to remove unbound Al(18)F and unlabeled peptide. The radiolabeling, including purification, was performed in 45 min. The specific activity was 45,000 GBq/mmol, and the peptide was stable in serum for 4 h at 37 degrees C. Labeling was performed at pH 4.1 in sodium citrate, sodium acetate, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, and 2-(N-morpholino)ethanesulfonic acid buffer and was optimal in sodium acetate buffer. The apparent 50% inhibitory concentration of the (19)F-labeled IMP466 determined on AR42J cells was 3.6 nM. Biodistribution studies at 2 h after injection showed a high tumor uptake of (18)F-IMP466 (28.3 +/- 5.2 percentage injected dose per gram [%ID/g]; tumor-to-blood ratio, 300 +/- 90), which could be blocked by an excess of unlabeled peptide (8.6 +/- 0.7 %ID/g), indicating that the accumulation in the tumor was receptor-mediated. Biodistribution of (68)Ga-IMP466 was similar to that of (18)F-IMP466. (18)F-IMP466 was stable in vivo, because bone uptake was only 0.4 +/- 0.2 %ID/g, whereas free Al(18)F accumulated rapidly in the bone (36.9 +/- 5.0 %ID/g at 2 h after injection). Small-animal PET/CT scans showed excellent tumor delineation and high preferential accumulation in the tumor. CONCLUSION NOTA-octreotide could be labeled rapidly and efficiently with (18)F using a 2-step, 1-pot method. The compound was stable in vivo and showed rapid accretion in somatostatin receptor subtype 2-expressing AR42J tumors in nude mice. This method can be used to label other NOTA-conjugated compounds with (18)F.
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Affiliation(s)
- Peter Laverman
- Department of Nuclear Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Maschauer S, Einsiedel J, Haubner R, Hocke C, Ocker M, Hübner H, Kuwert T, Gmeiner P, Prante O. Markierung und Glycosylierung von Peptiden mithilfe der Klick-Chemie: ein allgemeiner Ansatz zur Synthese von18F-Glycopeptiden, leistungsstarken Tracern für die Positronenemissionstomographie. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.200904137] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Colombo M, Bianchi A. Click chemistry for the synthesis of RGD-containing integrin ligands. Molecules 2010; 15:178-97. [PMID: 20110882 PMCID: PMC6256992 DOI: 10.3390/molecules15010178] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 12/19/2009] [Accepted: 12/31/2009] [Indexed: 12/26/2022] Open
Abstract
In the last few years click chemistry reactions, and in particular copper-catalyzed cycloadditions, have been used intensively for the preparation of new bioconjugate molecules and materials applicable to biomedical and pharmaceutical areas. This review will be focused on conjugates of the tripeptide Arg-Gly-Asp formed by means of click chemistry reactions. This sequence is a well known binding motif for specific transmembrane proteins and is involved in cellular adhesion to the extracellular matrix, allowing the selective recognition of the biomolecule or polymer in which it is incorporated.
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Affiliation(s)
- Matteo Colombo
- NiKem Research, via Zambeletti 25, 20021 Baranzate, Milan, Italy
- Author to whom correspondence should be addressed; E-Mail: ; Fax: +39-235694-7606
| | - Aldo Bianchi
- Consorzio Interdisciplinare di Studi Biomolecolari ed Applicazioni Industriali (CISI), Via Fantoli 16/15, 20138 Milan, Italy; E-Mail: (A.B.)
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Maschauer S, Einsiedel J, Haubner R, Hocke C, Ocker M, Hübner H, Kuwert T, Gmeiner P, Prante O. Labeling and Glycosylation of Peptides Using Click Chemistry: A General Approach to 18F-Glycopeptides as Effective Imaging Probes for Positron Emission Tomography. Angew Chem Int Ed Engl 2009; 49:976-9. [DOI: 10.1002/anie.200904137] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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