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Du Y, Coughlin JM, Brosnan MK, Chen A, Shinehouse LK, Abdallah R, Lodge MA, Mathews WB, Liu C, Wu Y, Minn I, Finley P, Hall AW, Lesniak WG, Dannals RF, Horti AG, Pomper MG. First-in-human imaging using [ 11C]MDTC: a radiotracer targeting the cannabinoid receptor type 2. Eur J Nucl Med Mol Imaging 2023; 50:2386-2393. [PMID: 36877235 DOI: 10.1007/s00259-023-06170-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 02/18/2023] [Indexed: 03/07/2023]
Abstract
PURPOSE We report findings from the first-in-human study of [11C]MDTC, a radiotracer developed to image the cannabinoid receptor type 2 (CB2R) with positron emission tomography (PET). METHODS Ten healthy adults were imaged according to a 90-min dynamic PET protocol after bolus intravenous injection of [11C]MDTC. Five participants also completed a second [11C]MDTC PET scan to assess test-retest reproducibility of receptor-binding outcomes. The kinetic behavior of [11C]MDTC in human brain was evaluated using tissue compartmental modeling. Four additional healthy adults completed whole-body [11C]MDTC PET/CT to calculate organ doses and the whole-body effective dose. RESULTS [11C]MDTC brain PET and [11C]MDTC whole-body PET/CT was well-tolerated. A murine study found evidence of brain-penetrant radiometabolites. The model of choice for fitting the time activity curves (TACs) across brain regions of interest was a three-tissue compartment model that includes a separate input function and compartment for the brain-penetrant metabolites. Regional distribution volume (VT) values were low, indicating low CB2R expression in the brain. Test-retest reliability of VT demonstrated a mean absolute variability of 9.91%. The measured effective dose of [11C]MDTC was 5.29 μSv/MBq. CONCLUSION These data demonstrate the safety and pharmacokinetic behavior of [11C]MDTC with PET in healthy human brain. Future studies identifying radiometabolites of [11C]MDTC are recommended before applying [11C]MDTC PET to assess the high expression of the CB2R by activated microglia in human brain.
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Affiliation(s)
- Yong Du
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Jennifer M Coughlin
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins Medical Institutions, Baltimore, MD, 21287, USA
| | - Mary Katherine Brosnan
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Allen Chen
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Laura K Shinehouse
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Rehab Abdallah
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Martin A Lodge
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - William B Mathews
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Chen Liu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Yunkou Wu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Il Minn
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Paige Finley
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Andrew W Hall
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Wojciech G Lesniak
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Robert F Dannals
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Andrew G Horti
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA
| | - Martin G Pomper
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St., JHOC 3223, Baltimore, MD, 21287, USA.
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins Medical Institutions, Baltimore, MD, 21287, USA.
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Ellison PA, Olson AP, Barnhart TE, Hoffman SLV, Reilly SW, Makvandi M, Bartels JL, Murali D, DeJesus OT, Lapi SE, Bednarz B, Nickles RJ, Mach RH, Engle JW. Improved production of 76Br, 77Br and 80mBr via CoSe cyclotron targets and vertical dry distillation. Nucl Med Biol 2020; 80-81:32-36. [PMID: 31575457 PMCID: PMC9066421 DOI: 10.1016/j.nucmedbio.2019.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 08/11/2019] [Accepted: 09/04/2019] [Indexed: 01/11/2023]
Abstract
INTRODUCTION The radioisotopes of bromine are uniquely suitable radiolabels for small molecule theranostic radiopharmaceuticals but are of limited availability due to production challenges. Significantly improved methods were developed for the production and radiochemical isolation of clinical quality 76Br, 77Br, and 80mBr. The radiochemical quality of the radiobromine produced using these methods was tested through the synthesis of a novel 77Br-labeled inhibitor of poly (ADP-ribose) polymerase-1 (PARP-1), a DNA damage response protein. METHODS 76Br, 77Br, and 80mBr were produced in high radionuclidic purity via the proton irradiation of novel isotopically-enriched Co76Se, Co77Se, and Co80Se intermetallic targets, respectively. Radiobromine was isolated through thermal chromatographic distillation in a vertical furnace assembly. The 77Br-labeled PARP inhibitor was synthesized via copper-mediated aryl boronic ester radiobromination. RESULTS Cyclotron production yields were 103 ± 10 MBq∙μA-1∙h-1 for 76Br, 88 ± 10 MBq∙μA-1∙h-1 for 80mBr at 16 MeV and 17 ± 1 MBq∙μA-1∙h-1 for 77Br at 13 MeV. Radiobromide isolation yields were 76 ± 11% in a small volume of aqueous solution. The synthesized 77Br-labeled PARP-1 inhibitor had a measured apparent molar activity up to 700 GBq/μmol at end of synthesis. CONCLUSIONS A novel selenium alloy target enabled clinical-scale production of 76Br, 77Br, and 80mBr with high apparent molar activities, which was used to for the production of a new 77Br-labeled inhibitor of PARP-1. ADVANCES IN KNOWLEDGE New methods for the cyclotron production and isolation of radiobromine improved the production capacity of 77Br by a factor of three and 76Br by a factor of six compared with previous methods. IMPLICATIONS FOR PATIENT CARE Preclinical translational research of 77Br-based Auger electron radiotherapeutics, such as those targeting PARP-1, will require the production of GBq-scale 77Br, which necessitates next-generation, high-yielding, isotopically-enriched cyclotron targets, such as the novel intermetallic Co77Se.
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Affiliation(s)
- Paul A Ellison
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
| | - Aeli P Olson
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Todd E Barnhart
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sabrina L V Hoffman
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sean W Reilly
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Mehran Makvandi
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Jennifer L Bartels
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Dhanabalan Murali
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Onofre T DeJesus
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Suzanne E Lapi
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Bryan Bednarz
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA; Department of Engineering Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Robert J Nickles
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Robert H Mach
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Jonathan W Engle
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA; Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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3
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Swastika, Chaturvedi S, Kaul A, Hazari PP, Jha P, Pal S, Lal S, Singh B, Barthélémy P, Mishra AK. Evaluation of BBB permeable nucleolipid (NLDPU): A di-C15-ketalised palmitone appended uridine as neuro-tracer for SPECT. Int J Pharm 2019; 565:269-282. [DOI: 10.1016/j.ijpharm.2019.04.074] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 04/16/2019] [Accepted: 04/27/2019] [Indexed: 12/17/2022]
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Chaturvedi S, Mishra AK. Small Molecule Radiopharmaceuticals - A Review of Current Approaches. Front Med (Lausanne) 2016; 3:5. [PMID: 26942181 PMCID: PMC4763069 DOI: 10.3389/fmed.2016.00005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 01/15/2016] [Indexed: 12/24/2022] Open
Abstract
Radiopharmaceuticals are an integral component of nuclear medicine and are widely applied in diagnostics and therapy. Though widely applied, the development of an “ideal” radiopharmaceutical can be challenging. Issues such as specificity, selectivity, sensitivity, and feasible chemistry challenge the design and synthesis of radiopharmaceuticals. Over time, strategies to address the issues have evolved by making use of new technological advances in the fields of biology and chemistry. This review presents the application of few advances in design and synthesis of radiopharmaceuticals. The topics covered are bivalent ligand approach and lipidization as part of design modifications for enhanced selectivity and sensitivity and novel synthetic strategies for optimized chemistry and radiolabeling of radiopharmaceuticals.
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Affiliation(s)
- Shubhra Chaturvedi
- Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organisation , Delhi , India
| | - Anil K Mishra
- Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organisation , Delhi , India
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Faheem A, Bokhari T, Roohi S, Mushtaq A, Sohaib M. 99mTc-Daunorubicin a potential brain imaging and theranostic agent: synthesis, quality control, characterization, biodistribution and scintigraphy. Nucl Med Biol 2013; 40:148-52. [DOI: 10.1016/j.nucmedbio.2012.08.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 08/19/2012] [Accepted: 08/27/2012] [Indexed: 11/30/2022]
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Morgenroth A, Vogg AT, Mottaghy FM, Schmaljohann J. Targeted endoradiotherapy using nucleotides. Methods 2011; 55:203-14. [PMID: 21782950 DOI: 10.1016/j.ymeth.2011.06.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 06/24/2011] [Accepted: 06/28/2011] [Indexed: 11/15/2022] Open
Abstract
Increased cellular proliferation is an integral part of the cancer phenotype. Hence, the sustained and continued demand on supply of DNA building blocks during the DNA replication presents a potential target for therapeutic intervention. For this propose, the α and Auger electron emitting nucleotides analogs are attractive for targeted endoradiotherapy, given that DNA of malignant cells is selectively addressed. This review summarizes development and preclinical and clinical studies of endoradiotherapeutic acting nucleoside analogs with a special focus on thymidine analogs.
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Affiliation(s)
- Agnieszka Morgenroth
- Department of Nuclear Medicine, University Hospital Aachen, RWTH, Pauwelsstraße 30, D-52074 Aachen, Germany.
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Szajek LP, Kao CHK, Kiesewetter DO, Sassaman MB, Lang L, Plascjak P, Eckelman WC. Semi-remote production of Br-76 and preparation of high specific activity radiobrominated pharmaceuticals for PET studies. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.92.4.291.35605] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The PET radionuclide 76Br (t1/2=16.2 h) can be easily produced utilizing the nuclear reaction As(3He,2n)76Br. We use high-purity arsenic targets and isolate radioactive bromide by chromic acid oxidation followed by simple distillation of [76Br] hydrogen bromide using a semi-remote apparatus. Use of reagents with little or no carrier bromine yields high specific activity radiobrominated pharmaceuticals prepared from the distilled [76Br] hydrogen bromide.
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Nimmagadda S, Shields AF. The role of DNA synthesis imaging in cancer in the era of targeted therapeutics. Cancer Metastasis Rev 2008; 27:575-87. [PMID: 18512023 DOI: 10.1007/s10555-008-9148-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Non-specific targets such as DNA and microtubules have been the mainstay of cancer therapeutics and the most effective clinical agents until a decade ago. Advances in genetics, molecular and cellular biology over the past decade led to the development of a new generation of agents that are far more specific and effective. In contrast to progress seen with therapeutic agents, general monitoring targets such as proliferation imaging are just gaining momentum and targeted imaging is still in its infancy. In these paradoxical times, this review assesses the role of proliferation imaging in monitoring the efficacy of targeted therapeutics.
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Affiliation(s)
- Sridhar Nimmagadda
- Russel H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231, USA.
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9
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Kao CHK, Xie HL, Liao CH, Chen WM, Kao PF. [18F]FBAU 3′,5′-dibenzoate, a lipophilic prodrug, enhances brain uptake of the cell proliferation tracer [18F]FBAU. Nucl Med Biol 2008; 35:635-43. [DOI: 10.1016/j.nucmedbio.2008.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Revised: 04/02/2008] [Accepted: 04/05/2008] [Indexed: 12/17/2022]
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10
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Vogg ATJ, Buck AK, Schmid M, Neumaier B, Wczasek K, Zlatopolskiy BD, Reske SN. Synthesis and biodistribution of 3′-fluoro-5-[131I]iodo-2′-deoxyuridine: a comparative study of [131I]FLIdU and [18F]FLT. Nucl Med Biol 2007; 34:273-81. [PMID: 17383577 DOI: 10.1016/j.nucmedbio.2006.12.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2006] [Revised: 11/20/2006] [Accepted: 12/25/2006] [Indexed: 10/23/2022]
Abstract
The radioiodinated 3'-fluorothymidine (FLT) analogue 3'-fluoro-5-[(131)I]iodo-2'-deoxyuridine ([(131)I]FLIdU) was synthesized, with iodine mimicking the methyl group of pyrimidine. [(131)I]FLIdU was accessible by direct electrophilic iodination using Iodogen as oxidant. Optimized amounts of the oxidant allowed radiochemical yields of about 70% after a reaction time of 10 min in an aqueous buffer medium at 90 degrees C. The uptake of [(131)I]FLIdU in a DoHH2 leukemia xenograft mouse model and in healthy mice revealed moderate FLIdU accumulation, followed by a significant washout of activity in proliferating tissues such as splenic and tumor tissues. In contrast, intraperitoneal coinjection with [(18)F]FLT showed high uptake and high activity retention up to 2 h, in both splenic and tumor tissues. Uptake in stomach tissues and increasing fractions of [(131)I]iodide in urine indicated metabolic instability of [(131)I]FLIdU due to rapid deiodination. Therefore, [(131)I]FLIdU alone does not seem to be a promising compound, neither for diagnostic imaging nor for potential therapeutic applications.
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Alauddin MM, Shahinian A, Park R, Tohme M, Fissekis JD, Conti PS. Synthesis of 2′-deoxy-2′-[18F]fluoro-5-bromo-1-β-D-arabinofuranosyluracil ([18F]-FBAU) and 2′-deoxy-2′-[18F]fluoro-5-chloro-1-β-D-arabinofuranosyl-uracil ([18F]-FCAU), and their biological evaluation as markers for gene expression. Nucl Med Biol 2004; 31:399-405. [PMID: 15093809 DOI: 10.1016/j.nucmedbio.2003.12.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2003] [Accepted: 12/26/2003] [Indexed: 10/26/2022]
Abstract
[(18)F]-FBAU and [(18)F]-FCAU have been synthesized and evaluated in vivo as markers for HSV1-tk gene expression. At 2 hours, uptake of [(18)F]-FBAU and [(18)F]-FCAU in HSV1-tk-positive tumors was 7.9-fold and 6.0-fold higher than the control tumors, respectively. Micro-PET images also showed very high uptake in HSV-tk tumors. Compared to [(14)C]-FMAU, total uptake of [(18)F]-FBAU and [(18)F]-FCAU was similar in tk-positive cells, but the uptake ratio (tk+/wild) was higher. [(18)F]-FBAU and [(18)F]-FCAU appear to be potential PET imaging agents for gene expression.
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Affiliation(s)
- Mian M Alauddin
- Department of Radiology, PET Imaging Science Center, University of Southern California, 2250 Alcazar Street, Suite 135V, Los Angeles, CA 90033, USA.
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Toyohara J, Hayashi A, Sato M, Gogami A, Tanaka H, Haraguchi K, Yoshimura Y, Kumamoto H, Yonekura Y, Fujibayashi Y. Development of radioiodinated nucleoside analogs for imaging tissue proliferation: comparisons of six 5-iodonucleosides. Nucl Med Biol 2003; 30:687-96. [PMID: 14499326 DOI: 10.1016/s0969-8051(03)00081-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of this study was to determine the most suitable iodonucleoside analogs for use in tissue proliferation imaging by means of single photon emission tomography (SPECT). In this study, 5-[(125)I]iodo-(2-deoxy-2-fluoro-4-thio-beta-D-arabinofuranosyl)uracil ([(125)I]FITAU, 1E) and 5-[(125)I]iodo-1-methyl-(2-deoxy-2-bromo-beta-D-arabinofuranosyl)uracil ([(125)I]IMBAU, 1F) were synthesized and their biological data were compared with previously published results regarding 4'-thio nucleoside analogs and the reference compound 5-[(125)I]iodo-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)uracil ([(125)I]FIAU, 1D). 5-Iodo-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)uracil (FIAU, 2D), 5-iodo-(2-deoxy-2-fluoro-4-thio-beta-D-arabinofuranosyl)uracil (FITAU, 2E), and 5-iodo-1-methyl-(2-deoxy-2-bromo-beta-D-arabinofuranosyl)uracil (IMBAU, 2F) were successfully labeled with (125)I and their in vitro cytosolic thymidine kinase (TK(1)) phosphorylation, recombinant thymidine phosphorylase enzymatic catabolism, TK(1)-dependent cell uptake, and in vivo biodistribution in normal mice were evaluated. Five compounds (1B, 1C, 1D, 1E, and 1F) were stable against C-N glycoside degradation induced by recombinant thymidine phosphorylase. However, 5-[(125)I]iodo-2'-deoxyuridine ([(125)I]IUdR, 1A) was not shown to be stable against such degradation. The TK(1) assay showed that [(125)I]FIAU (1D) expressed 16% of the phosphorylation potential of [(125)I]IUdR (1A). Furthermore, [(125)I]FITAU (1E) was shown to have reduced phosphorylation potential, in comparison with that of [(125)I]IUdR (1A) (<0.01). [(125)I]IMBAU (1F) did not show any phosphorylation. In vitro cell uptake and in vivo proliferation-selective uptake of each nucleoside was largely dependent on its potential as a TK(1) substrate. Neither [(125)I]FITAU (1E) nor [(125)I]IMBAU (1F) were shown to have distinct TK(1)-dependent cell uptake and retention in the proliferating tissues. From these results, we concluded that [(125)I]FITAU (1E) and [(125)I]IMBAU (1F) are not effective as imaging agents of cell proliferation. The biological data obtained with these nucleosides were compared, and requirements for the design of pharmaceutically useful radioiodinated nucleoside analogs were also considered.
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Affiliation(s)
- Jun Toyohara
- Research Center, Research and Development Division, Nihon Medi-Physics, Co., Ltd., Chiba, Japan
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Beattie BJ, Finn RD, Rowland DJ, Pentlow KS. Quantitative imaging of bromine‐76 and yttrium‐86 with PET: A method for the removal of spurious activity introduced by cascade gamma rays. Med Phys 2003; 30:2410-23. [PMID: 14528963 DOI: 10.1118/1.1595599] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Positron Emission Tomography of bromine-76 and yttrium-86 results in the detection of coincident events that are not strictly associated with annihilation photon pairs. Instead, these coincidences occur because prompt gamma rays emitted by these nuclides result in cascades of photons that are emitted within the timing window of the PET scanner. Pairs of detected photons from these cascades are not angularly correlated and therefore contain little information regarding the location of their source. Furthermore, these coincidences are not removed by correction procedures (e.g., randoms, scatter) routinely applied to PET data. If left uncorrected, the cascade coincidences will result in spurious apparent activity within the PET images. A correction, applied within projection space, that removes the cascade coincidence signal from septa-in (i.e., two-dimensional) datasets is proposed and tested on phantom data.
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Affiliation(s)
- Bradley J Beattie
- Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
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Saturnino C, Buonerba M, Boatto G, Pascale M, Moltedo O, de Napoli L, Montesarchio D, Lancelot JC, de Caprariis P. Synthesis and preliminary biological evaluation of a new pyridocarbazole derivative covalently linked to a thymidine nucleoside as a potential targeted antitumoral agent. I. Chem Pharm Bull (Tokyo) 2003; 51:971-4. [PMID: 12913238 DOI: 10.1248/cpb.51.971] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The therapy of human cancer is one of the more pursued goals by medicinal chemistry research. Most of the compounds clinically used as a treatment owe their efficacy to their cytotoxic interaction (direct or indirect) with nuclear DNA. This interaction results in the inhibition of DNA synthesis and the degradation of nucleic strands. Ellipticine is a naturally occurring 6H-pyrido[4,3-b]carbazole alkaloid endowed with antitumor activity, and several ellipticine derivatives have been used in clinical trials. We previously reported some 1,4-dimethyl-9H-carbazole derivatives structurally related to ellipticine. The purpose of our research was to transform the pyridocarbazole in a prodrug so that it would have more penetration in the tumor cells and block their replication. Our prodrug is slowly hydrolyzed in human plasma in the corresponding acid. From these preliminary results, we deduce that our compound can block cellular replication. Our hypothesis is that the antitumoral activity is probably related to the induction of damage to DNA, without cellular lysis in the short term.
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Affiliation(s)
- Carmela Saturnino
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Salerno, Salerno, Italy
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