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Nekolla SG, Rischpler C, Higuchi T. Preclinical Imaging of Cardiovascular Disesase. Semin Nucl Med 2023; 53:586-598. [PMID: 37268498 DOI: 10.1053/j.semnuclmed.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/24/2023] [Accepted: 04/26/2023] [Indexed: 06/04/2023]
Abstract
Noninvasive imaging techniques, such as SPECT, PET, CT, echocardiography, or MRI, have become essential in cardiovascular research. They allow for the evaluation of biological processes in vivo without the need for invasive procedures. Nuclear imaging methods, such as SPECT and PET, offer numerous advantages, including high sensitivity, reliable quantification, and the potential for serial imaging. Modern SPECT and PET imaging systems, equipped with CT and MRI components in order to get access to morphological information with high spatial resolution, are capable of imaging a wide range of established and innovative agents in both preclinical and clinical settings. This review highlights the utility of SPECT and PET imaging as powerful tools for translational research in cardiology. By incorporating these techniques into a well-defined workflow- similar to those used in clinical imaging- the concept of "bench to bedside" can be effectively implemented.
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Affiliation(s)
- Stephan G Nekolla
- Nuklearmedizinische Klinik der TU München, Munich, Germany; DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany.
| | | | - Takahiro Higuchi
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany; Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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2
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Renard I, Domarkas J, Poty S, Burke BP, Roberts DP, Goze C, Denat F, Cawthorne CJ, Archibald SJ. In vivo validation of 68Ga-labeled AMD3100 conjugates for PET imaging of CXCR4. Nucl Med Biol 2023; 120-121:108335. [PMID: 37068392 DOI: 10.1016/j.nucmedbio.2023.108335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 03/13/2023] [Accepted: 03/21/2023] [Indexed: 04/19/2023]
Abstract
INTRODUCTION The chemokine receptor CXCR4 has been shown to be over-expressed in multiple types of cancer and is usually associated with aggressive phenotypes and poor prognosis. Successfully targeting and imaging the expression level of this receptor in tumours could inform treatment selection and facilitate patient stratification. METHODS Known conjugates of AMD3100 that are specific to CXCR4 have been radiolabelled with gallium-68 and evaluated in naïve and tumour-bearing mice. Tumour uptake of the radiotracers was compared to the known CXCR4-specific PET imaging agent, [68Ga]Pentixafor. RESULTS Ex vivo biodistribution in naïve animals showed CXCR4-mediated uptake in the liver with both radiotracers, confirmed by blocking experiments with the high affinity CXCR4 antagonist Cu2CB-Bicyclam (IC50 = 3 nM). PET/CT imaging studies revealed one tracer to have a higher accumulation in the tumour (SUVMean of 0.89 ± 0.14 vs 0.32 ± 0.11). CXCR4-specificity of the best performing tracer was confirmed by administration of a blocking dose of Cu2CB-Bicyclam, showing a 3- and 6-fold decrease in tumour and liver uptake, respectively. CONCLUSION AND ADVANCES IN KNOWLEDGE This initial study offers some interesting insights on the impact of some structural features on the pharmacokinetics and metabolic stability of the radiotracer. Additionally, as Pentixafor only binds to human CXCR4, the development of CXCR4-targeted imaging agents that bind to the receptor across different species could significantly help with preclinical evaluation of new CXCR4-specific therapeutics.
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Affiliation(s)
- Isaline Renard
- Centre for Biomedicine and PET Research Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK
| | - Juozas Domarkas
- Centre for Biomedicine and PET Research Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK
| | - Sophie Poty
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université Bourgogne Franche-Comté, Dijon, France
| | - Benjamin P Burke
- Centre for Biomedicine and PET Research Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK
| | - David P Roberts
- Centre for Biomedicine and PET Research Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK
| | - Christine Goze
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université Bourgogne Franche-Comté, Dijon, France.
| | - Franck Denat
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université Bourgogne Franche-Comté, Dijon, France.
| | - Christopher J Cawthorne
- Centre for Biomedicine and PET Research Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK; Nuclear Medicine & Molecular Imaging, Department of Imaging & Pathology, KU Leuven, 3000 Leuven, Belgium.
| | - Stephen J Archibald
- Centre for Biomedicine and PET Research Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK.
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Myocardial Uptake of 68Ga-Pentixafor in a Patient With Systemic Amyloidosis. Clin Nucl Med 2022; 47:1118-1120. [PMID: 36342801 DOI: 10.1097/rlu.0000000000004406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
ABSTRACT A 55-year-old man presented with chest tightness and lower-limb edema for 1 year. Laboratory and imaging examinations suggested cardiac amyloidosis. Both 18F-FDG and 68Ga-pentixafor PET/CT showed increased uptake in the myocardium of the left ventricle, whereas the bone marrow had diffusely mild uptake of 68Ga-pentixafor without bone destruction. 99mTc-MDP bone scintigraphy also detected extraosseous uptake in the heart, gut, kidneys, and soft tissue. The biopsy of the abdominal subcutaneous fat confirmed amyloid deposits, and the patient was finally diagnosed with primary systemic amyloidosis. This case demonstrated that cardiac amyloidosis might show increased 68Ga-pentixafor uptake in myocardium.
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Rischpler C, Seifert R. Combined PET and MRI for the masses! : At least for the cardiac ones. J Nucl Cardiol 2022; 29:1518-1519. [PMID: 34935109 PMCID: PMC9351608 DOI: 10.1007/s12350-021-02881-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 10/31/2021] [Indexed: 11/15/2022]
Affiliation(s)
- Christoph Rischpler
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - Robert Seifert
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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5
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Nuclear Molecular Imaging of Cardiac Remodeling after Myocardial Infarction. Pharmaceuticals (Basel) 2022; 15:ph15020183. [PMID: 35215296 PMCID: PMC8875369 DOI: 10.3390/ph15020183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 01/28/2022] [Accepted: 01/28/2022] [Indexed: 12/03/2022] Open
Abstract
The role of molecular imaging technologies in detecting, evaluating, and monitoring cardiovascular disease and their treatment is expanding rapidly. Gradually replacing the conventional anatomical or physiological approaches, molecular imaging strategies using biologically targeted markers provide unique insight into pathobiological processes at molecular and cellular levels and allow for cardiovascular disease evaluation and individualized therapy. This review paper will discuss currently available and developing molecular-based single-photon emission computed tomography (SPECT) and positron emission tomography (PET) imaging strategies to evaluate post-infarction cardiac remodeling. These approaches include potential targeted methods of evaluating critical biological processes, such as inflammation, angiogenesis, and scar formation.
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Zacherl MJ, Todica A, Wängler C, Schirrmacher R, Hajebrahimi MA, Pircher J, Li X, Lindner S, Brendel M, Bartenstein P, Massberg S, Brunner S, Lehner S, Hacker M, Huber BC. Molecular imaging of cardiac CXCR4 expression in a mouse model of acute myocardial infarction using a novel 68Ga-mCXCL12 PET tracer. J Nucl Cardiol 2021; 28:2965-2975. [PMID: 32676914 PMCID: PMC8709820 DOI: 10.1007/s12350-020-02262-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 06/08/2020] [Indexed: 01/16/2023]
Abstract
BACKGROUND The chemokine receptor CXCR4 and its ligand CXCL12 have been shown to be a possible imaging and therapeutic target after myocardial infarction (MI). The murine-based and mouse-specific 68Ga-mCXCL12 PET tracer could be suitable for serial in vivo quantification of cardiac CXCR4 expression in a murine model of MI. METHODS AND RESULTS At days 1-6 after MI, mice were intravenously injected with 68Ga-mCXCL12. Autoradiography was performed and the infarct-to-remote ratio (I/R) was determined. In vivo PET imaging with 68Ga-mCXCL12 was conducted on days 1-6 after MI and the percentage of the injected dose (%ID/g) of the tracer uptake in the infarct area was calculated. 18F-FDG-PET was performed for anatomical landmarking. Ex vivo autoradiography identified CXCR4 upregulation in the infarct region with an increasing I/R after 12 hours (1.4 ± 0.3), showing a significant increase until day 2 (4.5 ± 0.6), followed by a plateau phase (day 4) and decrease after 10 days (1.3 ± 1.0). In vivo PET imaging identified similar CXCR4 upregulation in the infarct region which peaked around day 3 post MI (9.7 ± 5.0 %ID/g) and then subsequently decreased by day 6 (2.8 ± 1.0 %ID/g). CONCLUSION Noninvasive molecular imaging of cardiac CXCR4 expression using a novel, murine-based, and specific 68Ga-mCXCL12 tracer is feasible both ex vivo and in vivo.
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Affiliation(s)
| | - Andrei Todica
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Carmen Wängler
- Biomedical Chemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Mannheim, Germany
| | - Ralf Schirrmacher
- Department of Oncology, Division of Oncological Imaging, University of Alberta, Edmonton, AB, Canada
| | | | - Joachim Pircher
- Department of Cardiology, University Hospital of Munich, LMU Munich, Munich, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
| | - Xiang Li
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Simon Lindner
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Matthias Brendel
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Peter Bartenstein
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Steffen Massberg
- Department of Cardiology, University Hospital of Munich, LMU Munich, Munich, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
| | - Stefan Brunner
- Department of Cardiology, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Sebastian Lehner
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
- Ambulatory Healthcare Center Dr. Neumaier & Colleagues, Radiology, Nuclear Medicine, Radiation Therapy, Regensburg, Germany
| | - Marcus Hacker
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.
| | - Bruno C Huber
- Department of Cardiology, University Hospital of Munich, LMU Munich, Munich, Germany
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MacAskill MG, Stadulyte A, Williams L, Morgan TEF, Sloan NL, Alcaide-Corral CJ, Walton T, Wimberley C, McKenzie CA, Spath N, Mungall W, BouHaidar R, Dweck MR, Gray GA, Newby DE, Lucatelli C, Sutherland A, Pimlott SL, Tavares AAS. Quantification of Macrophage-Driven Inflammation During Myocardial Infarction with 18F-LW223, a Novel TSPO Radiotracer with Binding Independent of the rs6971 Human Polymorphism. J Nucl Med 2021; 62:536-544. [PMID: 32859708 PMCID: PMC8049364 DOI: 10.2967/jnumed.120.243600] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/28/2020] [Indexed: 01/09/2023] Open
Abstract
Myocardial infarction (MI) is one of the leading causes of death worldwide, and inflammation is central to tissue response and patient outcomes. The 18-kDa translocator protein (TSPO) has been used in PET as an inflammatory biomarker. The aims of this study were to screen novel, fluorinated, TSPO radiotracers for susceptibility to the rs6971 genetic polymorphism using in vitro competition binding assays in human brain and heart; assess whether the in vivo characteristics of our lead radiotracer, 18F-LW223, are suitable for clinical translation; and validate whether 18F-LW223 can detect macrophage-driven inflammation in a rat MI model. Methods: Fifty-one human brain and 29 human heart tissue samples were screened for the rs6971 polymorphism. Competition binding assays were conducted with 3H-PK11195 and the following ligands: PK11195, PBR28, and our novel compounds (AB5186 and LW223). Naïve rats and mice were used for in vivo PET kinetic studies, radiometabolite studies, and dosimetry experiments. Rats underwent permanent coronary artery ligation and were scanned using PET/CT with an invasive input function at 7 d after MI. For quantification of PET signal in the hypoperfused myocardium, K1 (rate constant for transfer from arterial plasma to tissues) was used as a surrogate marker of perfusion to correct the binding potential for impaired radiotracer transfer from plasma to tissue (BPTC). Results: LW223 binding to TSPO was not susceptible to the rs6971 genetic polymorphism in human brain and heart samples. In rodents, 18F-LW223 displayed a specific uptake consistent with TSPO expression, a slow metabolism in blood (69% of parent at 120 min), a high plasma free fraction of 38.5%, and a suitable dosimetry profile (effective dose of 20.5-24.5 μSv/MBq). 18F-LW223 BPTC was significantly higher in the MI cohort within the infarct territory of the anterior wall relative to the anterior wall of naïve animals (32.7 ± 5.0 vs. 10.0 ± 2.4 cm3/mL/min, P ≤ 0.001). Ex vivo immunofluorescent staining for TSPO and CD68 (macrophage marker) resulted in the same pattern seen with in vivo BPTC analysis. Conclusion:18F-LW223 is not susceptible to the rs6971 genetic polymorphism in in vitro assays, has favorable in vivo characteristics, and is able to accurately map macrophage-driven inflammation after MI.
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Affiliation(s)
- Mark G MacAskill
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Agne Stadulyte
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Lewis Williams
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Timaeus E F Morgan
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Nikki L Sloan
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Carlos J Alcaide-Corral
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Tashfeen Walton
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Catriona Wimberley
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Chris-Anne McKenzie
- MRC Edinburgh Brain Tissue Bank, University of Edinburgh, Edinburgh, United Kingdom
| | - Nick Spath
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - William Mungall
- Bioresearch and Veterinary Services, University of Edinburgh, Edinburgh, United Kingdom
| | - Ralph BouHaidar
- Forensic Pathology, University of Edinburgh, Edinburgh, United Kingdom
| | - Marc R Dweck
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Gillian A Gray
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - David E Newby
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Andrew Sutherland
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Sally L Pimlott
- School of Medicine, University of Glasgow, Glasgow, United Kingdom; and
- NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
| | - Adriana A S Tavares
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
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8
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Imaging Inflammation with Positron Emission Tomography. Biomedicines 2021; 9:biomedicines9020212. [PMID: 33669804 PMCID: PMC7922638 DOI: 10.3390/biomedicines9020212] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 01/28/2021] [Accepted: 02/12/2021] [Indexed: 12/19/2022] Open
Abstract
The impact of inflammation on the outcome of many medical conditions such as cardiovascular diseases, neurological disorders, infections, cancer, and autoimmune diseases has been widely acknowledged. However, in contrast to neurological, oncologic, and cardiovascular disorders, imaging plays a minor role in research and management of inflammation. Imaging can provide insights into individual and temporospatial biology and grade of inflammation which can be of diagnostic, therapeutic, and prognostic value. There is therefore an urgent need to evaluate and understand current approaches and potential applications for imaging of inflammation. This review discusses radiotracers for positron emission tomography (PET) that have been used to image inflammation in cardiovascular diseases and other inflammatory conditions with a special emphasis on radiotracers that have already been successfully applied in clinical settings.
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9
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Congestive Heart Failure. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00050-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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10
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Manabe O, Oyama-Manabe N, Tamaki N. Positron emission tomography/MRI for cardiac diseases assessment. Br J Radiol 2020; 93:20190836. [PMID: 32023123 DOI: 10.1259/bjr.20190836] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Functional imaging tools have emerged in the last few decades and are increasingly used to assess the function of the human heart in vivo. Positron emission tomography (PET) is used to evaluate myocardial metabolism and blood flow. Magnetic resonance imaging (MRI) is an essential tool for morphological and functional evaluation of the heart. In cardiology, PET is successfully combined with CT for hybrid cardiac imaging. The effective integration of two imaging modalities allows simultaneous data acquisition combining functional, structural and molecular imaging. After PET/CT has been successfully accepted for clinical practices, hybrid PET/MRI is launched. This review elaborates the current evidence of PET/MRI in cardiovascular imaging and its expected clinical applications for a comprehensive assessment of cardiovascular diseases while highlighting the advantages and limitations of this hybrid imaging approach.
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Affiliation(s)
- Osamu Manabe
- Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Japan
| | - Noriko Oyama-Manabe
- Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Japan
| | - Nagara Tamaki
- Department of Radiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
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Osl T, Schmidt A, Schwaiger M, Schottelius M, Wester HJ. A new class of PentixaFor- and PentixaTher-based theranostic agents with enhanced CXCR4-targeting efficiency. Am J Cancer Res 2020; 10:8264-8280. [PMID: 32724470 PMCID: PMC7381729 DOI: 10.7150/thno.45537] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 06/05/2020] [Indexed: 02/07/2023] Open
Abstract
Non-invasive PET imaging of CXCR4 expression in cancer and inflammation as well as CXCR4-targeted radioligand therapy (RLT) have recently found their way into clinical research by the development of the theranostic agents [68Ga]PentixaFor (cyclo(D-Tyr1-D-[NMe]Orn2(AMBS-[68Ga]DOTA)-Arg3-Nal4-Gly5) = [68Ga]DOTA-AMBS-CPCR4) and [177Lu/90Y]PentixaTher (cyclo(D-3-iodo-Tyr1-D-[NMe]Orn2(AMBS-[177Lu/90Y]DOTA)-Arg3-Nal4-Gly5) = [177Lu/90Y]DOTA-AMBS-iodoCPCR4). Although convincing clinical results have already been obtained with both agents, this study was designed to further investigate the required structural elements for improved ligand-receptor interaction for both peptide cores (CPCR4 and iodoCPCR4). To this aim, a series of DOTA-conjugated CPCR4- and iodoCPCR4-based ligands with new linker structures, replacing the AMBA-linker in PentixaFor and PentixaTher, were synthesized and evaluated. Methods: The in vitro investigation of the novel compounds alongside with the reference peptides PentixaFor and PentixaTher encompassed the determination of hCXCR4 and mCXCR4 affinity (IC50) of the respective natGa-, natLu-, natY- and natBi-complexes in Jurkat and Eμ-myc 1080 cells using [125I]FC-131 and [125I]CPCR4.3 as radioligands, respectively, as well as the evaluation of the internalization and externalization kinetics of selected 68Ga- and 177Lu-labeled compounds in hCXCR4-transfected Chem-1 cells. Comparative small animal PET imaging studies (1h p.i.) as well as in vivo biodistribution studies (1, 6 and 48h p.i.) were performed in Daudi (human B cell lymphoma) xenograft bearing CB17 SCID mice. Results: Based on the affinity data and cellular uptake studies, [68Ga/177Lu]DOTA-r-a-ABA-CPCR4 and [68Ga/177Lu]DOTA-r-a-ABA-iodoCPCR4 (with r-a-ABA = D-Arg-D-Ala-4-aminobenzoyl-) were selected for further evaluation. Both analogs show app. 10-fold enhanced hCXCR4 affinity compared to the respective references [68Ga]PentixaFor and [177Lu]PentixaTher, four times higher cellular uptake in hCXCR4 expressing cells and improved cellular retention. Unfortunately, the improved in vitro binding and uptake characteristics of [68Ga]DOTA-r-a-ABA-CPCR4 and -iodoCPCR4 could not be recapitulated in initial PET imaging studies; both compounds showed similar uptake in the Daudi xenografts as [68Ga]PentixaFor, alongside with higher background accumulation, especially in the kidneys. However, the subsequent biodistribution studies performed for the corresponding 177Lu-labeled analogs revealed a clear superiority of [177Lu]DOTA-r-a-ABA-CPCR4 and [177Lu]DOTA-r-a-ABA-iodoCPCR4 over [177Lu]PentixaTher with respect to tumor uptake (18.3±3.7 and 17.2±2.0 %iD/g, respectively, at 1h p.i. vs 12.4±3.7%iD/g for [177Lu]PentixaTher) as well as activity retention in tumor up to 48h. Especially for [177Lu]DOTA-r-a-ABA-CPCR4 with its low background accumulation, tumor/organ ratios at 48h were 2- to 4-fold higher than those obtained for [177Lu]PentixaTher (except for kidney). Conclusions: The in-depth evaluation of a series of novel CPCR4- and iodoCPCR4 analogs with modified linker structure has yielded reliable structure-activity relationships. It was generally observed that a) AMBA-by-ABA-substitution leads to enhanced ligand internalization, b) the extension of the ABA-linker by two additional amino acids (DOTA-Xaa2-Xaa1-ABA-) provides sufficient linker length to minimize the interaction of the [M3+]DOTA-chelate with the receptor, and that c) introduction of a cationic side chain (Xaa2) greatly enhances receptor affinity of the constructs, obliterating the necessity for Tyr1-iodination of the pentapeptide core to maintain high receptor affinity (such as in [177Lu]PentixaTher). As a result, [177Lu]DOTA-r-a-ABA-CPCR4 has emerged from this study as a powerful second-generation therapeutic CXCR4 ligand with greatly improved targeting efficiency and tumor retention and will be further evaluated in preclinical and clinical CXCR4-targeted dosimetry and RLT studies.
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12
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Schwaiger M, Nekolla SG. What did we learn from PET/MR? J Nucl Cardiol 2020; 27:899-902. [PMID: 31385222 DOI: 10.1007/s12350-019-01815-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 05/23/2019] [Indexed: 11/26/2022]
Affiliation(s)
| | - Stephan G Nekolla
- Department of Nuclear Medicine, Technical University of Munich, Munich, Germany
- DZHK (Deutsches, Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany
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13
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Rischpler C, Siebermair J, Kessler L, Quick HH, Umutlu L, Rassaf T, Antoch G, Herrmann K, Nensa F. Cardiac PET/MRI: Current Clinical Status and Future Perspectives. Semin Nucl Med 2020; 50:260-269. [PMID: 32284112 DOI: 10.1053/j.semnuclmed.2020.02.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Combined PET/MRI has now been in clinical routine for almost 10 years. Since then, it has not only had to face validation, comparison and research questions, it has also been increasingly used in clinical routine. A number of cardiovascular applications have become established here, whereby viability imaging and assessment of inflammatory and infiltrative processes in the heart are to be emphasized. However, further interesting applications are expected in the near future. This review summarizes the most important clinical applications on the one hand and mentions interesting areas of application in research on the other.
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Affiliation(s)
- Christoph Rischpler
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - Johannes Siebermair
- Department of Cardiology and Vascular Medicine, University Hospital Essen, West German Heart and Vascular Center, University of Duisburg-Essen, Essen, Germany
| | - Lukas Kessler
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Harald H Quick
- High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany; Erwin L Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany
| | - Lale Umutlu
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Tienush Rassaf
- Department of Cardiology and Vascular Medicine, University Hospital Essen, West German Heart and Vascular Center, University of Duisburg-Essen, Essen, Germany
| | - Gerald Antoch
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Düsseldorf, Düsseldorf, Germany
| | - Ken Herrmann
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Felix Nensa
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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15
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Adlere I, Caspar B, Arimont M, Dekkers S, Visser K, Stuijt J, de Graaf C, Stocks M, Kellam B, Briddon S, Wijtmans M, de Esch I, Hill S, Leurs R. Modulators of CXCR4 and CXCR7/ACKR3 Function. Mol Pharmacol 2019; 96:737-752. [DOI: 10.1124/mol.119.117663] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/14/2019] [Indexed: 02/06/2023] Open
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16
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Heo GS, Zhao Y, Sultan D, Zhang X, Detering L, Luehmann HP, Zhang X, Li R, Choksi A, Sharp S, Levingston S, Reichert DE, Sun G, Razani B, Li S, Weilbaecher KN, Dehdashti F, Wooley KL, Liu Y. Assessment of Copper Nanoclusters for Accurate in Vivo Tumor Imaging and Potential for Translation. ACS APPLIED MATERIALS & INTERFACES 2019; 11:19669-19678. [PMID: 31074257 PMCID: PMC7811435 DOI: 10.1021/acsami.8b22752] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Nanoparticles have been widely used for preclinical cancer imaging. However, their successful clinical translation is largely hampered by potential toxicity, unsatisfactory detection of malignancy at early stages, inaccurate diagnosis of tumor biomarkers, and histology for imaging-guided treatment. Herein, a targeted copper nanocluster (CuNC) is reported with high potential to address these challenges for future translation. Its ultrasmall structure enables efficient renal/bowel clearance, minimized off-target effects in nontargeted organs, and low nonspecific tumor retention. The pH-dependent in vivo dissolution of CuNCs affords minimal toxicity and potentially selective drug delivery to tumors. The intrinsic radiolabeling through the direct addition of 64Cu to CuNC (64Cu-CuNCs-FC131) synthesis offers high specific activity for sensitive and accurate detection of CXCR4 via FC131-directed targeting in novel triple negative breast cancer (TNBC) patient-derived xenograft mouse models and human TNBC tissues. In summary, this study not only reveals the potential of CXCR4-targeted 64Cu-CuNCs for TNBC imaging in clinical settings, but also provides a useful strategy to design and assess the translational potential of nanoparticles for cancer theranostics.
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Affiliation(s)
- Gyu Seong Heo
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - Yongfeng Zhao
- Department of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39217, United States
| | - Deborah Sultan
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - Xiaohui Zhang
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - Lisa Detering
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - Hannah P. Luehmann
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - Xiangyu Zhang
- Department of Medicine, Washington University, St. Louis, MO 63110, United States
| | - Richen Li
- Department of Chemistry, Department of Chemical Engineering, Department of Materials Science & Engineering, and Laboratory for Synthetic-Biologic Interactions, Texas A&M University, College Station, TX 77842, United States
| | - Ankur Choksi
- University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | | | - Sidney Levingston
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - David E. Reichert
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - Guorong Sun
- Department of Chemistry, Department of Chemical Engineering, Department of Materials Science & Engineering, and Laboratory for Synthetic-Biologic Interactions, Texas A&M University, College Station, TX 77842, United States
| | - Babak Razani
- Department of Medicine, Washington University, St. Louis, MO 63110, United States
| | - Shunqiang Li
- Department of Medicine, Washington University, St. Louis, MO 63110, United States
| | | | - Farrokh Dehdashti
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
| | - Karen L. Wooley
- Department of Chemistry, Department of Chemical Engineering, Department of Materials Science & Engineering, and Laboratory for Synthetic-Biologic Interactions, Texas A&M University, College Station, TX 77842, United States
| | - Yongjian Liu
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, United States
- Corresponding Author:
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18
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Beitzke D, Wielandner A, Wollenweber T, Vraka C, Pichler V, Uyanik-Uenal K, Zuckermann A, Greiser A, Hacker M, Loewe C. Assessment of sympathetic reinnervation after cardiac transplantation using hybrid cardiac PET/MRI: A pilot study. J Magn Reson Imaging 2019; 50:1326-1335. [PMID: 30892777 PMCID: PMC6766915 DOI: 10.1002/jmri.26722] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/01/2019] [Accepted: 03/02/2019] [Indexed: 12/12/2022] Open
Abstract
Background Sympathetic reinnervation after heart transplantation (HTX) is a known phenomenon, which has an impact on patient heart rate variability and exercise capacity. The impact of reinnervation on myocardial structure has not been evaluated yet. Propose To evaluate the feasibility of simultaneous imaging of cardiac reinnervation and cardiac structure using a hybrid PET/MRI system. Study type Prospective / pilot study. Subjects Ten patients, 4–21 years after cardiac transplantation. Field Strength/Sequence 3 T hybrid PET/MRI system. Cine SSFP, T1 mapping (modified Look–Locker inversion recovery sequence) pre/postcontrast as well as dynamic [11C]meta‐hydroxyephedrine ([11C]mHED) PET. Assessment All MRI and PET parameters were evaluated by experienced readers using dedicated postprocessing software packages for cardiac MRI and PET. For all parameters a 16‐segment model for the left ventricle was applied. Statistical Tests Mann–Whitney U‐test; Spearman correlations. Results Thirty‐six of 160 myocardial segments showed evidence of reinnervation by PET. On a segment‐based analysis, mean native T1 relaxation times were nonsignificantly altered in segments with evidence of reinnervation (1305 ± 151 msec vs. 1270 ± 112 msec; P = 0.1), whereas mean extracellular volume (ECV) was significantly higher in segments with evidence of reinnervation (35.8 ± 11% vs. 30.9 ± 7%; P = 0.019). There were no significant differences in wall motion (WM) and wall thickening (WT) between segments with or without reinnervation (mean WM: 7.6 ± 4 mm vs. group B: 9.3 ± 7 mm [P = 0.13]; WT: 79 ± 63% vs. 94 ± 74% [P = 0.27]) under resting conditions. Data Conclusion The assessment of cardiac reinnervation using a hybrid PET/MRI system is feasible. Segments with evidence of reinnervation by PET showed nonsignificantly higher T1 relaxation times and a significantly higher ECV, suggesting a higher percentage of diffuse fibrosis in these segments, without impairment of rest WM and WT. Level of Evidence: 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:1326–1335.
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Affiliation(s)
- Dietrich Beitzke
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University of Vienna, Vienna, Austria
| | - Alice Wielandner
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University of Vienna, Vienna, Austria
| | - Tim Wollenweber
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Chrysoula Vraka
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Verena Pichler
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Keziban Uyanik-Uenal
- Department of Surgery, Division of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Andreas Zuckermann
- Department of Surgery, Division of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | | | - Marcus Hacker
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Christian Loewe
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University of Vienna, Vienna, Austria
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Molecular Imaging to Monitor Left Ventricular Remodeling in Heart Failure. CURRENT CARDIOVASCULAR IMAGING REPORTS 2019. [DOI: 10.1007/s12410-019-9487-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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20
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Rischpler C, Nekolla SG, Heusch G, Umutlu L, Rassaf T, Heusch P, Herrmann K, Nensa F. Cardiac PET/MRI-an update. Eur J Hybrid Imaging 2019; 3:2. [PMID: 34191143 PMCID: PMC8212244 DOI: 10.1186/s41824-018-0050-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 12/17/2018] [Indexed: 12/21/2022] Open
Abstract
It is now about 8 years since the first whole-body integrated PET/MRI has been installed. First, reports on technical characteristics and system performance were published. Early after, reports on the first use of PET/MRI in oncological patients were released. Interestingly, the first article on the application in cardiology was a review article, which was published before the first original article was put out. Since then, researchers have gained a lot experience with the PET/MRI in various cardiovascular diseases and an increasing number on auspicious indications is appearing. In this review article, we give an overview on technical updates within these last years with potential impact on cardiac imaging and summarize those scenarios where PET/MRI plays a pivotal role in cardiovascular medicine.
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Affiliation(s)
- C Rischpler
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - S G Nekolla
- Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.) partner site Munich Heart alliance, Munich, Germany
| | - G Heusch
- Institute for Pathophysiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - L Umutlu
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - T Rassaf
- Department of Cardiology and Vascular Medicine, University Hospital Essen, West German Heart and Vascular Center, University of Duisburg-Essen, Essen, Germany
| | - P Heusch
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Düsseldorf, Düsseldorf, Germany
| | - K Herrmann
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - F Nensa
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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Kircher M, Herhaus P, Schottelius M, Buck AK, Werner RA, Wester HJ, Keller U, Lapa C. CXCR4-directed theranostics in oncology and inflammation. Ann Nucl Med 2018; 32:503-511. [PMID: 30105558 PMCID: PMC6182637 DOI: 10.1007/s12149-018-1290-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 08/08/2018] [Indexed: 12/17/2022]
Abstract
Given its prominent role in inflammation and cancer biology, the C-X-C motif chemokine receptor 4 (CXCR4) has gained a lot of attention in the recent years. This review gives a short overview of the physiology and pathology of chemokines and chemokine receptors and then focuses on the current experience of targeting CXCR4, using radiolabeled receptor ligands suitable for positron emission tomography (PET) imaging, in both hematologic and solid malignancy as well as in inflammatory conditions. Additionally, CXCR4-directed endoradiotherapy (ERT) as a new treatment option is discussed.
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Affiliation(s)
- Malte Kircher
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Peter Herhaus
- Internal Medicine III, Hematology and Medical Oncology, Technische Universität München, Munich, Germany
| | - Margret Schottelius
- Pharmaceutical Radiochemistry, Technische Universität München, Munich, Germany
| | - Andreas K Buck
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Rudolf A Werner
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
- Division of Nuclear Medicine and Molecular Imaging, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, Technische Universität München, Munich, Germany
| | - Ulrich Keller
- Internal Medicine III, Hematology and Medical Oncology, Technische Universität München, Munich, Germany
| | - Constantin Lapa
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany.
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22
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Kim DY, Cho SG, Bom HS. Emerging Tracers for Nuclear Cardiac PET Imaging. Nucl Med Mol Imaging 2018; 52:266-278. [PMID: 30100939 PMCID: PMC6066491 DOI: 10.1007/s13139-018-0521-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/05/2018] [Accepted: 04/12/2018] [Indexed: 12/16/2022] Open
Abstract
Myocardial perfusion imaging using positron emission tomography (PET) has several advantages over single photon emission computed tomography (SPECT). The recent advances in SPECT technology have shown promise, but there is still a large need for PET in the clinical management of coronary artery disease (CAD). Especially, absolute quantification of myocardial blood flow (MBF) using PET is extremely important. In spite of considerable advances in the diagnosis of CAD, novel PET radiopharmaceuticals remain necessary for the diagnosis of CAD because clinical use of current cardiac radiotracers is limited by their physical characteristics, such as decay mode, emission energy, and half-life. Thus, the use of a radioisotope that has proper characteristics and a proper half-life to develop myocardial perfusion agents could overcome these limitations. In this review, the current state of cardiac PET and a general overview of novel 18F or 68Ga-labeled radiotracers, including their radiosynthesis, in vivo characterization, and evaluation, are provided. The future perspectives are discussed in terms of their potential usefulness based on new image analysis methods and hybrid imaging.
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Affiliation(s)
- Dong-Yeon Kim
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, 322 Seoyang-ro Hwasun-eup, Hwasun-gun, Jeollanam-do 58128 Republic of Korea
| | - Sang-Geon Cho
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, 322 Seoyang-ro Hwasun-eup, Hwasun-gun, Jeollanam-do 58128 Republic of Korea
| | - Hee-Seung Bom
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, 322 Seoyang-ro Hwasun-eup, Hwasun-gun, Jeollanam-do 58128 Republic of Korea
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23
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Feng M, Li Z, Wang D, Wang F, Wang C, Wang C, Ding F. MicroRNA-210 aggravates hypoxia-induced injury in cardiomyocyte H9c2 cells by targeting CXCR4. Biomed Pharmacother 2018; 102:981-987. [PMID: 29710553 DOI: 10.1016/j.biopha.2018.03.151] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 03/23/2018] [Accepted: 03/26/2018] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Myocardial infarction (MI), a leading cause of mortality, is identified as the myocardial necrosis due to prolonged ischemia. Hypoxia, resulting from ischemia, induces cell apoptosis during MI. Since miR-210 is a hypoxia inducible factor, we aimed to explore the functional role of miR-210 in hypoxic H9c2 cells. METHODS Hypoxia-induced cell injury was evaluated according to cell viability, apoptosis and expression of apoptosis-associated proteins. miR-210 expression after hypoxia was tested. Then, miR-210 was overexpressed or silenced, and its effects on viability and apoptosis of H9c2 cells under normoxia and hypoxia were measured. Utilizing bioinformatics method, possible target genes of miR-210 were screened, and the interaction between miR-210 and target gene was investigated. Moreover, the effect of co-transfections with microRNAs and small interfering RNAs on hypoxia-induced cell injury as well as the possible involved signaling pathways was also determined. RESULTS Hypoxia induced cell injury and up-regulation of miR-210 in H9c2 cells. Hypoxia-induced cell injury was aggravated by miR-210 overexpression but was attenuated by miR-210 suppression. CXC chemokine receptor 4 (CXCR4) was a target gene of miR-210, and CXCR4 inhibition could reverse the effects of miR-210 inhibition on H9c2 cells. Furthermore, the key kinases involved in the SMAD and mTOR signaling pathways were down-regulated by hypoxia, and the down-regulations were reversed by miR-210 suppression through modulating CXCR4. CONCLUSION miR-210 was up-regulated in hypoxic H9c2 cells. Suppression of miR-210 attenuated hypoxia-induced cell injury in H9c2 cells by targeting CXCR4, along with activations of the SMAD and mTOR signaling pathways.
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Affiliation(s)
- Min Feng
- Department of Cardiology, Binzhou Medical University Hospital, Binzhou, 256603, China.
| | - Zongqing Li
- Department of Cardiology, Binzhou Medical University Hospital, Binzhou, 256603, China
| | - Dong Wang
- Department of Cardiology, Binzhou Medical University Hospital, Binzhou, 256603, China.
| | - Fang Wang
- Department of State-owned Assets Management, Binzhou Medical University Hospital, Binzhou, 256603, China
| | - Chenyan Wang
- Department of Cardiology, Binzhou Medical University Hospital, Binzhou, 256603, China
| | - Chunfang Wang
- Department of Cardiology, Binzhou Medical University Hospital, Binzhou, 256603, China
| | - Faming Ding
- Department of Cardiology, Binzhou Medical University Hospital, Binzhou, 256603, China
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Prospective of 68Ga Radionuclide Contribution to the Development of Imaging Agents for Infection and Inflammation. CONTRAST MEDIA & MOLECULAR IMAGING 2018. [PMID: 29531507 PMCID: PMC5817300 DOI: 10.1155/2018/9713691] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
During the last decade, the utilization of 68Ga for the development of imaging agents has increased considerably with the leading position in the oncology. The imaging of infection and inflammation is lagging despite strong unmet medical needs. This review presents the potential routes for the development of 68Ga-based agents for the imaging and quantification of infection and inflammation in various diseases and connection of the diagnosis to the treatment for the individualized patient management.
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Walenkamp AME, Lapa C, Herrmann K, Wester HJ. CXCR4 Ligands: The Next Big Hit? J Nucl Med 2017; 58:77S-82S. [PMID: 28864616 DOI: 10.2967/jnumed.116.186874] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 06/02/2017] [Indexed: 12/12/2022] Open
Abstract
The G protein-coupled protein receptor C-X-C chemokine receptor 4 (CXCR4) is an attractive target for cancer diagnosis and treatment, as it is overexpressed in many solid and hematologic cancers. Binding of its ligand, C-X-C chemokine ligand 12 (CXCL12), results in receptor internalization and activation of several signal transduction pathways, such as phosphoinositide 3-kinase/protein kinase B, which are critical in cell proliferation, angiogenesis, development of metastasis, and survival. Also, the CXCR4-CXCL12 axis is involved in the interaction between hematopoietic stem cells (as well as hematologic and solid tumor cells) and their protective microenvironment. This interaction can be disrupted by CXCR4 antagonists. This concept is being used clinically to harvest hematopoietic stem or progenitor cells from bone marrow and to sensitize cancer cells to conventional chemotherapy and radiotherapy, and the potential to overcome tumor microenvironment-driven immunosuppression is being explored. This review focuses on new strategies for improvement of cancer treatment by targeting of the CXCR4-CXCL12 interaction. Because of its critical role in cancer, many peptidic and nonpeptidic ligands with different modes of antagonistic activity against the CXCR4-CXCL12 axis have been developed, with some of them reaching clinical trials. Molecular imaging with recently developed radiolabeled CXCR4 ligands could facilitate the selection of patients who might benefit from directed targeted therapy, including CXCR4-directed endoradiotherapy.
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Affiliation(s)
- Annemiek M E Walenkamp
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Constantin Lapa
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Ken Herrmann
- Department of Nuclear Medicine, University Hospital Essen, Essen, Germany.,Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, Los Angeles, California
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, Technische Universität München, Munich, Germany; and.,Scintomics GmbH, Fuerstenfeldbruck, Germany
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26
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Nekolla SG, van Marwick S, Schachoff S, Kunze KP, Rischpler C. Cardiovascular PET/MRI: Technical Considerations and Outlook. CURRENT CARDIOVASCULAR IMAGING REPORTS 2017. [DOI: 10.1007/s12410-017-9435-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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27
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Jackson IM, Scott PJ, Thompson S. Clinical Applications of Radiolabeled Peptides for PET. Semin Nucl Med 2017; 47:493-523. [DOI: 10.1053/j.semnuclmed.2017.05.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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28
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Schottelius M, Osl T, Poschenrieder A, Hoffmann F, Beykan S, Hänscheid H, Schirbel A, Buck AK, Kropf S, Schwaiger M, Keller U, Lassmann M, Wester HJ. [ 177Lu]pentixather: Comprehensive Preclinical Characterization of a First CXCR4-directed Endoradiotherapeutic Agent. Theranostics 2017; 7:2350-2362. [PMID: 28744319 PMCID: PMC5525741 DOI: 10.7150/thno.19119] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 03/11/2017] [Indexed: 12/30/2022] Open
Abstract
Purpose: Based on the clinical relevance of the chemokine receptor 4 (CXCR4) as a molecular target in cancer and on the success of [68Ga]pentixafor as an imaging probe for high-contrast visualization of CXCR4-expression, the spectrum of clinical CXCR4-targeting was expanded towards peptide receptor radionuclide therapy (PRRT) by the development of [177Lu]pentixather. Experimental design: CXCR4 affinity, binding specificity, hCXCR4 selectivity and internalization efficiency of [177Lu]pentixather were evaluated using different human and murine cancer cell lines. Biodistribution studies (1, 6, 48, 96h and 7d p.i.) and in vivo metabolite analyses were performed using Daudi-lymphoma bearing SCID mice. Extrapolated organ doses were cross-validated with human dosimetry (pre-therapeutic and during [177Lu]pentixather PRRT) in a patient with multiple myeloma (MM). Results: [177Lu]pentixather binds with high affinity, specificity and selectivity to hCXCR4 and shows excellent in vivo stability. Consequently, and supported by >96% plasma protein binding and a logP=-1.76, delaying whole-body clearance of [177Lu]pentixather, tumor accumulation was high and persistent, both in the Daudi model and the MM patient. Tumor/background ratios (7d p.i.) in mice were 499±202, 33±7, 4.0±0.8 and 116±22 for blood, intestine, kidney and muscle, respectively. In the patient, high tumor/kidney and tumor/liver dose ratios of 3.1 and 6.4 were observed during [177Lu]pentixather PRRT (7.8 GBq), with the kidneys being the dose-limiting organs. Conclusions: [177Lu]pentixather shows excellent in vivo CXCR4-targeting characteristics and a suitable pharmacokinetic profile, leading to high tumor uptake and retention and thus high radiation doses to tumor tissue during PRRT, suggesting high clinical potential of this [68Ga]pentixafor/[177Lu]pentixather based CXCR4-targeted theranostic concept.
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Affiliation(s)
- Margret Schottelius
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meissner-Strasse 3, 85748 Garching, Germany
| | - Theresa Osl
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meissner-Strasse 3, 85748 Garching, Germany
| | - Andreas Poschenrieder
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meissner-Strasse 3, 85748 Garching, Germany
| | - Frauke Hoffmann
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meissner-Strasse 3, 85748 Garching, Germany
| | - Seval Beykan
- Department of Nuclear Medicine, Universität Würzburg, Oberdürrbacher Str. 6, 97080 Würzburg, Germany
| | - Heribert Hänscheid
- Department of Nuclear Medicine, Universität Würzburg, Oberdürrbacher Str. 6, 97080 Würzburg, Germany
| | - Andreas Schirbel
- Department of Nuclear Medicine, Universität Würzburg, Oberdürrbacher Str. 6, 97080 Würzburg, Germany
| | - Andreas K. Buck
- Department of Nuclear Medicine, Universität Würzburg, Oberdürrbacher Str. 6, 97080 Würzburg, Germany
| | - Saskia Kropf
- Scintomics GmbH, Lindach 4, 82256 Fürstenfeldbruck, Germany
| | - Markus Schwaiger
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany
- Deutsches Konsortium für translationale Krebsforschung (DKTK) and Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Ulrich Keller
- III. Medical Department, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany
- Deutsches Konsortium für translationale Krebsforschung (DKTK) and Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Michael Lassmann
- Department of Nuclear Medicine, Universität Würzburg, Oberdürrbacher Str. 6, 97080 Würzburg, Germany
| | - Hans-Jürgen Wester
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meissner-Strasse 3, 85748 Garching, Germany
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Schwaiger M, Kunze K, Rischpler C, Nekolla SG. PET/MR: Yet another Tesla? J Nucl Cardiol 2017; 24:1019-1031. [PMID: 27659455 DOI: 10.1007/s12350-016-0665-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 08/19/2016] [Indexed: 12/20/2022]
Abstract
After the successful introduction of PET/CT as a multimodality imaging technique, PET/MR has subsequently emerged as an attractive instrumentation for applications in neurology, oncology, and cardiology. Simultaneous data acquisition combining structural, functional, and molecular imaging provides a unique platform to link various aspects of cardiac performance for the non-invasive characterization of cardiovascular disease phenotypes. Specifically, tissue characterization by MR techniques with and without contrast agents allows for functional parameters such as LGE, myocardial perfusion, and T1 maps as well as an estimate of extracellular volume. PET tracers excel by their high sensitivity and specificity, thus supplementing the functional tissue characterization by MRI. Although the clinical applications are yet to be validated , the first experience with PET/MR suggests future applications in the area of vascular imaging (unstable plaque) as well as in the characterization of inflammatory processes involving the heart. Ischemic heart disease can be comprehensively assessed by integrating regional function, perfusion, and viability. Future technical improvements leading to less costly PET/MR instrumentation are necessary to support routine clinical application of this promising technique in cardiology.
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Affiliation(s)
- Markus Schwaiger
- Department of Nuclear Medicine, Klinikum rechts der Isar der Technischen Universität München, Ismaninger Straße 22, 81675, Munich, Germany.
| | - Karl Kunze
- Department of Nuclear Medicine, Klinikum rechts der Isar der Technischen Universität München, Ismaninger Straße 22, 81675, Munich, Germany
| | - Christoph Rischpler
- Department of Nuclear Medicine, Klinikum rechts der Isar der Technischen Universität München, Ismaninger Straße 22, 81675, Munich, Germany
| | - Stephan G Nekolla
- Department of Nuclear Medicine, Klinikum rechts der Isar der Technischen Universität München, Ismaninger Straße 22, 81675, Munich, Germany
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Abstract
Cardiovascular diseases are a consequence of genetic and environmental risk factors that together generate arterial wall and cardiac pathologies. Blood vessels connect multiple systems throughout the entire body and allow organs to interact via circulating messengers. These same interactions facilitate nervous and metabolic system's influence on cardiovascular health. Multiparametric imaging offers the opportunity to study these interfacing systems' distinct processes, to quantify their interactions, and to explore how these contribute to cardiovascular disease. Noninvasive multiparametric imaging techniques are emerging tools that can further our understanding of this complex and dynamic interplay. Positron emission tomography/magnetic resonance imaging and multichannel optical imaging are particularly promising because they can simultaneously sample multiple biomarkers. Preclinical multiparametric diagnostics could help discover clinically relevant biomarker combinations pivotal for understanding cardiovascular disease. Interfacing systems important to cardiovascular disease include the immune, nervous, and hematopoietic systems. These systems connect with classical cardiovascular organs, such as the heart and vasculature, and with the brain. The dynamic interplay between these systems and organs enables processes, such as hemostasis, inflammation, angiogenesis, matrix remodeling, metabolism, and fibrosis. As the opportunities provided by imaging expand, mapping interconnected systems will help us decipher the complexity of cardiovascular disease and monitor novel therapeutic strategies.
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Affiliation(s)
- Katrien Vandoorne
- From the Center for Systems Biology (K.V., M.N.) and Department of Imaging (K.V., M.N.), Massachusetts General Hospital and Harvard Medical School, Boston; and Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston (M.N.)
| | - Matthias Nahrendorf
- From the Center for Systems Biology (K.V., M.N.) and Department of Imaging (K.V., M.N.), Massachusetts General Hospital and Harvard Medical School, Boston; and Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston (M.N.).
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AlJaroudi W, Hage FG. Review of Cardiovascular Imaging in the Journal of Nuclear Cardiology in 2016. Part 1 of 2: Positron Emission Tomography, Computed Tomography and Magnetic Resonance. J Nucl Cardiol 2017; 24:649-656. [PMID: 28194727 DOI: 10.1007/s12350-017-0820-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 01/23/2017] [Indexed: 11/27/2022]
Abstract
Several original articles and editorials have been published in the Journal of Nuclear Cardiology last year. It has become a tradition at the beginning of each year to summarize some of these key articles (AlJaroudi and Hage in J Nucl Cardiol 22:507-512, 2015, 23:122-130, 2016; Hage and AlJaroudi in J Nucl Cardiol 22:714-719, 2015; 23:493-498, 2016). In this part one, we will discuss some of the progress made in patients with infiltrative disease, cardiomyopathies (non-ischemic, ischemic, and diabetic), hybrid and molecular imaging, using advancement in positron emission tomography, computed tomography, and magnetic resonance imaging.
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Affiliation(s)
- Wael AlJaroudi
- Division of Cardiovascular Medicine, Clemenceau Medical Center, Beirut, Lebanon.
| | - Fadi G Hage
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Lyons Harrison Research Building 314, 1900 University BLVD, Birmingham, AL, 35294, USA
- Section of Cardiology, Birmingham Veterans Affairs Medical Center, Birmingham, AL, USA
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Bailey DL, Pichler BJ, Gückel B, Barthel H, Beer AJ, Botnar R, Gillies R, Goh V, Gotthardt M, Hicks RJ, Lanzenberger R, la Fougere C, Lentschig M, Nekolla SG, Niederdraenk T, Nikolaou K, Nuyts J, Olego D, Riklund KÅ, Signore A, Schäfers M, Sossi V, Suminski M, Veit-Haibach P, Umutlu L, Wissmeyer M, Beyer T. Combined PET/MRI: from Status Quo to Status Go. Summary Report of the Fifth International Workshop on PET/MR Imaging; February 15-19, 2016; Tübingen, Germany. Mol Imaging Biol 2016; 18:637-50. [PMID: 27534971 PMCID: PMC5010606 DOI: 10.1007/s11307-016-0993-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This article provides a collaborative perspective of the discussions and conclusions from the fifth international workshop of combined positron emission tomorgraphy (PET)/magnetic resonance imaging (MRI) that was held in Tübingen, Germany, from February 15 to 19, 2016. Specifically, we summarise the second part of the workshop made up of invited presentations from active researchers in the field of PET/MRI and associated fields augmented by round table discussions and dialogue boards with specific topics. This year, this included practical advice as to possible approaches to moving PET/MRI into clinical routine, the use of PET/MRI in brain receptor imaging, in assessing cardiovascular diseases, cancer, infection, and inflammatory diseases. To address perceived challenges still remaining to innovatively integrate PET and MRI system technologies, a dedicated round table session brought together key representatives from industry and academia who were engaged with either the conceptualisation or early adoption of hybrid PET/MRI systems. Discussions during the workshop highlighted that emerging unique applications of PET/MRI such as the ability to provide multi-parametric quantitative and visual information which will enable not only overall disease detection but also disease characterisation would eventually be regarded as compelling arguments for the adoption of PET/MR. However, as indicated by previous workshops, evidence in favour of this observation is only growing slowly, mainly due to the ongoing inability to pool data cohorts from independent trials as well as different systems and sites. The participants emphasised that moving from status quo to status go entails the need to adopt standardised imaging procedures and the readiness to act together prospectively across multiple PET/MRI sites and vendors.
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Affiliation(s)
- D L Bailey
- Department of Nuclear Medicine, Royal North Shore Hospital, and Faculty of Health Sciences, University of Sydney, Sydney, Australia
| | - B J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard-Karls-Universität, Tübingen, Germany
| | - B Gückel
- Department of Interventional and Diagnostic Radiology, Eberhard-Karls-Universität, Tübingen, Germany
| | - H Barthel
- Department of Nuclear Medicine, University Clinic, Leipzig, Germany
| | - A J Beer
- Department of Nuclear Medicine, Ulm University, Ulm, Germany
| | - R Botnar
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK
| | | | - V Goh
- Division of Imaging Sciences and Biomedical Engineering, Department of Cancer Imaging, King's College London, London, UK
| | - M Gotthardt
- Department of Nuclear Medicine, Radboud University, Nijmegen, The Netherlands
| | - R J Hicks
- Peter MacCallum Cancer Centre, Melbourne, Australia
| | - R Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - C la Fougere
- Division of Nuclear Medicine and clinical Molecular Imaging, Department of Radiology, University of Tübingen, Tübingen, Germany
| | - M Lentschig
- ZEMODI, Zentrum für Moderne Diagnostik, Bremen, Germany
| | - S G Nekolla
- Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - T Niederdraenk
- Strategy and Innovation Technology Center, Siemens Healthcare GmbH, Erlangen, Germany
| | - K Nikolaou
- Department of Interventional and Diagnostic Radiology, Eberhard-Karls-Universität, Tübingen, Germany
| | - J Nuyts
- Department of Imaging and Pathology, Nuclear Medicine and Molecular Imaging, KU Leuven - University of Leuven, Leuven, Belgium
| | - D Olego
- Philips, 3000 Minuteman Road, Andover, MA, 01810, USA
| | - K Åhlström Riklund
- Department of Diagnostic Radiology, Radiation Sciences, Umeå University/Norrlands University Hospital, Umeå, Sweden
| | - A Signore
- Nuclear Medicine Unit, Departments of Medical-Surgical Sciences and Translational Medicine, "Sapienza" University of Rome, Rome, Italy
| | - M Schäfers
- Department of Nuclear Medicine, University Hospital Münster and European Institute for Molecular Imaging, University of Münster, Münster, Germany
| | - V Sossi
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
| | | | - P Veit-Haibach
- Department of Nuclear Medicine, University Hospital Zurich, Zurich, Switzerland
| | - L Umutlu
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - M Wissmeyer
- Department of Nuclear Medicine, University Hospital of Geneva, Geneva, Switzerland
| | - T Beyer
- Center for Medical Physics and Biomedical Engineering, General Hospital Vienna, Medical University Vienna, 4L, Waehringer Guertel 18-20, 1090, Vienna, Austria.
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Poschenrieder A, Schottelius M, Schwaiger M, Wester HJ. Preclinical evaluation of [(68)Ga]NOTA-pentixafor for PET imaging of CXCR4 expression in vivo - a comparison to [(68)Ga]pentixafor. EJNMMI Res 2016; 6:70. [PMID: 27655427 PMCID: PMC5031577 DOI: 10.1186/s13550-016-0227-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 09/17/2016] [Indexed: 01/20/2023] Open
Abstract
Background Due to its overexpression in a variety of tumor types, the chemokine receptor 4 (CXCR4) represents a highly relevant diagnostic and therapeutic target in nuclear oncology. Recently, [68Ga]pentixafor has emerged as an excellent imaging agent for positron emission tomography (PET) of CXCR4 expression in vivo. In this study, the corresponding [68Ga]-1,4,7-triazacyclononane-triacetic acid (NOTA) analog was preclinically evaluated and compared to the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) parent compound [68Ga]pentixafor. Methods NOTA-pentixafor was synthesized by combining solid and solution-phase peptide synthesis. The CXCR4 receptor affinities of [68Ga]pentixafor and [68Ga]NOTA-pentixafor were determined in competitive binding assays using the leukemic CXCR4-expressing Jurkat T-cell line and [125I]FC131 as the radioligand. Internalization and cell efflux assays were performed using CXCR4-transfected Chem-1 cells. Small-animal PET and biodistribution studies were carried out using Daudi-tumor bearing SCID mice. Results [68Ga]NOTA-pentixafor showed a 1.4-fold improved affinity towards CXCR4 (IC50). However, internalization efficiency into CXCR4+-Chem-1 cells was substantially decreased compared to [68Ga]pentixafor. Accordingly, small-animal PET imaging and biodistribution studies revealed a 9.5-fold decreased uptake of [68Ga]NOTA-pentixafor in Daudi lymphoma xenografts (1.7 ± 0.4 % vs 16.2 ± 3.8 % ID/g at 90 min p.i.) and higher levels of non-specific accumulation, primarily in the excretory organs such as the liver, intestines, and kidneys (2.3 ± 0.9 % vs 2.0 ± 0.3 % ID/g, 1.9 ± 0.8 % vs 0.7 ± 0.2 % ID/g, and 2.7 ± 1.1 % vs 1.7 ± 0.9 % ID/g, respectively). Conclusions Despite enhanced CXCR4-affinity in vitro, the [68Ga]NOTA-analog of pentixafor showed reduced CXCR4 targeting efficiency in vivo. In combination with enhanced background accumulation, this resulted in significantly inferior PET imaging contrast, and thus, [68Ga]NOTA-pentixafor offers no advantages over [68Ga]pentixafor.
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Affiliation(s)
- Andreas Poschenrieder
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748, Garching, Germany.
| | - Margret Schottelius
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748, Garching, Germany
| | - Markus Schwaiger
- Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, München, Germany
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748, Garching, Germany
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Abstract
Hybrid PET/MR imaging is a complex imaging modality that has raised high expectations not only for oncological and neurologic imaging applications, but also for cardiac imaging applications. Initially, physicians and physicists had to become accustomed to technical challenges including attenuation correction, gating, and more complex workflow and more elaborate image analysis as compared with PET/CT or standalone MR imaging. PET/MR imaging seems to be particularly valuable to assess inflammatory myocardial diseases (such as sarcoidosis), to cross-validate PET versus MR imaging data (eg, myocardial perfusion imaging), and to help validate novel biomarkers of various disease states (eg, postinfarction inflammation).
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