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Ogawa K, Masuda R, Mizuno Y, Makino A, Kozaka T, Kitamura Y, Kiyono Y, Shiba K, Odani A. Development of a novel radiobromine-labeled sigma-1 receptor imaging probe. Nucl Med Biol 2018; 61:28-35. [PMID: 29704822 DOI: 10.1016/j.nucmedbio.2018.03.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 02/11/2018] [Accepted: 03/21/2018] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Sigma-1 receptor is a target for tumor imaging. In a previous study, we synthesized a vesamicol analog, (+)-2-[4-(4-bromophenyl)piperidino]cyclohexanol [(+)-pBrV], with a high affinity for sigma-1 receptor, and synthesized radiobrominated (+)-pBrV. This radiobrominated (+)-pBrV showed high tumor uptake in tumor-bearing mice; however, radioactivity accumulation in normal tissues, such as the liver, was high. We assumed that the accumulation of (+)-pBrV in the non-target tissues was partially derived from its high lipophilicity; therefore, we synthesized and evaluated (+)-4-[1-(2-hydroxycyclohexyl)piperidine-4-yl]-2-bromophenol [(+)-BrV-OH], which is a more hydrophilic compound. Although we aimed to develop a PET tracer using 76Br, in these initial studies, we used 77Br because of its longer half-life. METHODS (+)-[77Br]BrV-OH was synthesized using the chloramine-T method with a radiochemical purity of 95%. Lipophilicity and affinity for sigma-1 receptor of (+)-[77Br]BrV-OH were determined, and biodistribution experiments were performed. We also performed an in vivo blocking study by co-injecting excess amounts of the sigma-1 receptor ligand, SA4503, into mice. RESULTS The lipophilicity and affinity for sigma-1 receptor of (+)-[77Br]BrV-OH were lower than those of (+)-[77Br]pBrV. (+)-[77Br]BrV-OH also showed high tumor uptake in biodistribution experiments in DU-145 tumor-bearing mice,. Although (+)-[77Br]pBrV was retained in most tissues, (+)-[77Br]BrV-OH was cleared from these tissues. In blocking studies, the co-injection of SA4503 significantly decreased the tumor uptake of (+)-[77Br]BrV-OH. CONCLUSION These results indicate that (+)-[76Br]BrV-OH has potential as a PET probe for sigma-1 receptor imaging.
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Affiliation(s)
- Kazuma Ogawa
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan; Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan.
| | - Ryohei Masuda
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Yoshiaki Mizuno
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Akira Makino
- Biomedical Imaging Research Center, University of Fukui, Yoshida 910-1193, Japan
| | - Takashi Kozaka
- Advanced Science Research Center, Kanazawa University, Kanazawa 920-8640, Japan
| | - Yoji Kitamura
- Advanced Science Research Center, Kanazawa University, Kanazawa 920-8640, Japan
| | - Yasushi Kiyono
- Biomedical Imaging Research Center, University of Fukui, Yoshida 910-1193, Japan
| | - Kazuhiro Shiba
- Advanced Science Research Center, Kanazawa University, Kanazawa 920-8640, Japan
| | - Akira Odani
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan
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Dasargyri A, Kümin CD, Leroux JC. Targeting Nanocarriers with Anisamide: Fact or Artifact? ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1603451. [PMID: 27885719 DOI: 10.1002/adma.201603451] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/08/2016] [Indexed: 05/19/2023]
Abstract
Encapsulating chemotherapeutics in nanoparticles can reduce the side effects of intravenous administration and improve their antitumor efficacy. Additionally, surface decoration of the nanocarriers with tumor-targeting ligands may enhance their specificity for cancer cells overexpressing the corresponding ligand-binding counterpart. The focus here is on anisamide, a low-molecular-weight benzamide derivative used as a tumor-directing moiety in functionalized nanosystems, based on its alleged interaction with Sigma receptors. The scintigraphic agents that initially inspired the use of anisamide for tumor targeting are described, and the published anisamide-tethered nanocarrier formulations are reviewed, together with a critical overview of the ligand's tumor-targeting properties. Moreover, anisamide's putative but dubious cellular target, the Sigma-1 receptor, is discussed with regard to its subcellular localization and implications in cancer. Data from in vivo studies reveal that the effect of anisamide on the antitumor efficacy of the decorated nanosystems varies considerably among the published reports. Together with the evidence questioning the interaction of anisamide with the Sigma receptors, the variability of anisamide's effect on the tumor deposition and the antitumor efficacy of the decorated drug carriers calls into question the extent of the ligand's tumor-targeting effect. Further research is necessary to elucidate the ligand's utility in tumor targeting.
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Affiliation(s)
- Athanasia Dasargyri
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich (ETHZ), Zurich, 8093, Switzerland
| | - Carole D Kümin
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich (ETHZ), Zurich, 8093, Switzerland
| | - Jean-Christophe Leroux
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich (ETHZ), Zurich, 8093, Switzerland
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Abstract
This review compares the biological and physiological function of Sigma receptors [σRs] and their potential therapeutic roles. Sigma receptors are widespread in the central nervous system and across multiple peripheral tissues. σRs consist of sigma receptor one (σ1R) and sigma receptor two (σ2R) and are expressed in numerous regions of the brain. The sigma receptor was originally proposed as a subtype of opioid receptors and was suggested to contribute to the delusions and psychoses induced by benzomorphans such as SKF-10047 and pentazocine. Later studies confirmed that σRs are non-opioid receptors (not an µ opioid receptor) and play a more diverse role in intracellular signaling, apoptosis and metabolic regulation. σ1Rs are intracellular receptors acting as chaperone proteins that modulate Ca2+ signaling through the IP3 receptor. They dynamically translocate inside cells, hence are transmembrane proteins. The σ1R receptor, at the mitochondrial-associated endoplasmic reticulum membrane, is responsible for mitochondrial metabolic regulation and promotes mitochondrial energy depletion and apoptosis. Studies have demonstrated that they play a role as a modulator of ion channels (K+ channels; N-methyl-d-aspartate receptors [NMDAR]; inositol 1,3,5 triphosphate receptors) and regulate lipid transport and metabolism, neuritogenesis, cellular differentiation and myelination in the brain. σ1R modulation of Ca2+ release, modulation of cardiac myocyte contractility and may have links to G-proteins. It has been proposed that σ1Rs are intracellular signal transduction amplifiers. This review of the literature examines the mechanism of action of the σRs, their interaction with neurotransmitters, pharmacology, location and adverse effects mediated through them.
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Affiliation(s)
- Colin G Rousseaux
- a Department of Pathology and Laboratory Medicine , University of Ottawa , Ottawa , ON , Canada and
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Banister SD, Manoli M, Kassiou M. The development of radiotracers for imaging sigma (σ) receptors in the central nervous system (CNS) using positron emission tomography (PET). J Labelled Comp Radiopharm 2014; 56:215-24. [PMID: 24285328 DOI: 10.1002/jlcr.3010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 11/19/2012] [Accepted: 11/20/2012] [Indexed: 11/10/2022]
Abstract
Sigma (σ) receptors are unique mammalian proteins, distributed in the central nervous system and elsewhere, which are increasingly implicated in the pathophysiology of virtually all major central nervous system disorders. The heterogeneous but wide distribution of σ1 in the brain has prompted the development of selective radiotracers for imaging these sites using positron emission tomography (PET). To date, some 50 carbon-11-labelled and fluorine-18-labelled candidate PET radioligands targeting σ receptors have been reported. The historical development of selective σ1 receptor ligands as potential PET imaging agents, as well as the radiochemistry and application of the most recently developed examples, is described herein.
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Affiliation(s)
- Samuel D Banister
- Brain and Mind Research Institute, The University of Sydney, NSW, 2050, Australia; School of Chemistry, The University of Sydney, NSW, 2006, Australia
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Malewski T, Milewicz T, Krzysiek J, Gregoraszczuk EL, Augustowska K. Regulation of Msx2 Gene Expression by Steroid Hormones in Human Nonmalignant and Malignant Breast Cancer Explants Cultured in Vitro. Cancer Invest 2009; 23:222-8. [PMID: 15945508 DOI: 10.1081/cnv-200055958] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Muscle segment homeobox genes, which regulate developmental programs and are expressed in embryonic and adult tissue, play a role in development of some malignancies. There are no reports on the expression of these families of genes in breast cancer tissue. The aim of this study was to compare expression of Msx2 gene in breast cancer of different genotypes as well as in surrounding nonmalignant tissues. Explants obtained during surgery were divided according to their sex steroid receptor status determined by immunocytochemistry. Four explants obtained from malignant and nonmalignant tissue of each individual patient were incubated in a control medium or with the addition of progesterone (10(-7) M) alone, estradiol 17 beta (10(-5) M) or both. The relative level of Msx2 transcripts was evaluated by a semiquantitative RT-PCR and cell proliferation by Alamar Blue test. Results of RT-PCR analysis showed that the relative expression of Msx2 gene depended on the presence of ER/PR receptors both in nonmalignant and malignant tissues Relative amount of Msx2 mRNA was the highest in surrounding nonmalignant ER+/PR- and ER-/PR+ tissue, whereas in ER-/PR- and ER+/PR+ tissue it was 1.4-1.6-fold lower. Tumorigenesis led to about a twofold decrease in the relative amount of Msx2 mRNA except for ER+/PR+ immunophenotype, where no changes were observed. Addition of estradiol or progesterone to the culture of ER-/PR- type tissue explants did not change significantly the relative amount of Msx2 gene mRNA. An opposite effect was observed in ER+/PR- type of tissue. Addition of estradiol alone, or estradiol and progesterone together to tissue culture explants decreased two to three fold the relative amount of Msx2 gene mRNA in both, malignant and surrounding tissues. Progesterone alone had no effect on Msx2 gene expression in this type of tissue. The most complicated regulation was observed in ER+/PR+ type of tissue. Culture of tissue explants supplemented with estradiol significantly increased the relative amount of Msx2 gene mRNA in the surrounding tissue. Progesterone enhanced the stimulatory effect of estradiol in surrounding tissues but not in the malignant tissue. Increased expression of Msx2 correlated with an increased proliferation in ER-/PR- and ER+/PR+ types, but not in ER+/PR- type of tissues. In conclusion, obtained results provide evidence that estrogen affects Msx2 gene expression. Significant changes in the relative amount of Msx2 gene mRNA and lack of canonical ERE element in 5'-upstream sequence of this gene suggest that regulation takes place indirectly probably by protein-protein interaction. The decrease in the relative amount of Msx2 gene mRNA in ER+/PR- type tumor suggests that progesterone also affects Msx2 gene expression by an indirect mechanism(s).
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Affiliation(s)
- T Malewski
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzêbiec, Poland
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Lu J, Kong D, Jia H, Deuther-Conrad W, Brust P, Wang X. Preparation and biological evaluation of99mTcN-4-(cyclohexylpiperazin-1-yl)-dithioformate as a potential sigma receptor imaging agent. J Labelled Comp Radiopharm 2007. [DOI: 10.1002/jlcr.1438] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Fan C, Jia H, Deuther-Conrad W, Brust P, Steinbach J, Liu B. Novel 99mTc labeled σ receptor ligand as a potential tumor imaging agent. ACTA ACUST UNITED AC 2006. [DOI: 10.1007/s11426-006-0169-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Kawamura K, Kubota K, Kobayashi T, Elsinga PH, Ono M, Maeda M, Ishiwata K. Evaluation of [11C]SA5845 and [11C]SA4503 for imaging of sigma receptors in tumors by animal PET. Ann Nucl Med 2005; 19:701-9. [PMID: 16444997 DOI: 10.1007/bf02985120] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Sigma receptors are expressed in a wide variety of tumor cell lines, and are expressed in proliferating cells. A radioligand for the visualization of sigma receptors could be useful for selective detection of primary tumors and their metastases, and for non-invasive assessment of tumor proliferative status. To this end we evaluated two sigma receptor ligands, [11C]SA5845 and [11C]SA4503. In an in vitro study, AH109A hepatoma showed moderate densities of sigma1 and sigma2 receptors, and VX-2 carcinoma showed a high density of sigma2 receptors: Bmax (fmol/mg protein) for sigma1 vs. sigma2, 1,700 vs. 1,200 for AH109A hepatoma and 800 vs. 10,000 for VX-2 carcinoma. In a cell growth assay in vitro, neither SA5845 nor SA4503 (<10 microM) showed any inhibitory effect on proliferation of the AH109A hepatoma cells. In rats, the uptake of [11C]SA5845 and [11C]SA4503 in AH109A tissues was accumulated over the first 60 minutes; however, the uptake of both tracers increased by co-injection with haloperidol as a sigma receptor ligand. On the other hand, in the PET studies of rabbits, the uptake of [11C]SA5845 in the VX-2 carcinoma was relatively higher than that of [11C]SA4503, because of a much higher density of sigma2 receptors compared to sigma1 receptors in the VX-2 tissue, and the uptake of both tracers in the VX-2 tissue was decreased by carrier-loading and pre-treatment with haloperidol ([11C]SA5845, 53% and 26%, respectively; [11C]SA4503, 41% and 22%, respectively at 30 minutes after injection). Therefore, [11C]SA5845 and [11C]SA4503 may be potential ligands for PET imaging of sigma receptor-rich tumors.
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Affiliation(s)
- Kazunori Kawamura
- Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Naka-cho 1-1, Itabashi-ku, Tokyo 173-0022, Japan.
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Bénard F, Turcotte É. Imaging in breast cancer: Single-photon computed tomography and positron-emission tomography. Breast Cancer Res 2005; 7:153-62. [PMID: 15987467 PMCID: PMC1175073 DOI: 10.1186/bcr1201] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Although mammography remains a key imaging method for the early detection and screening of breast cancer, the overall accuracy of this test remains low. Several radiopharmaceuticals have been proposed as adjunct imaging methods to characterize breast masses by single-photon-emission computed tomography (SPECT) and positron-emission tomography (PET). Useful in characterizing indeterminate palpable masses and in the detection of axillary metastases, these techniques are insufficiently sensitive to detect subcentimetric tumor deposits. Their role in staging nodal involvement of the axillary areas therefore currently remains limited. Several enzymes and receptors have been targeted for imaging breast cancers with PET. [18F]Fluorodeoxyglucose is particularly useful in the detection and staging of recurrent breast cancer and in assessing the response to chemotherapy. Several other ligands targeting proliferative activity, protein synthesis, and hormone and cell-membrane receptors may complement this approach by providing unique information about biological characteristics of breast cancer across primary and metastatic tumor sites.
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Affiliation(s)
- François Bénard
- Metabolic and Functional Imaging Center, Clinical Research Center, Centre hospitalier universitaire de Sherbrooke, Fleurimont, QC, Canada
| | - Éric Turcotte
- Metabolic and Functional Imaging Center, Clinical Research Center, Centre hospitalier universitaire de Sherbrooke, Fleurimont, QC, Canada
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Shiue CY, Welch MJ. Update on PET radiopharmaceuticals: life beyond fluorodeoxyglucose. Radiol Clin North Am 2004; 42:1033-53, viii. [PMID: 15488556 DOI: 10.1016/j.rcl.2004.08.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Twenty-eight years after its inception, 2-[18F]FDG- is still the most widely used radiopharmaceutical for PET studies, but numerous more specific radiotracers have been developed and applied in neuroscience and oncology. The advances in radiotracer chemistry, especially the nucleophilic substitution reaction, have played the pivotal role in synthesizing various no-carrier-added 18F-labeled radiotracers for PET studies of various receptor systems. This article lists some of the radiotracers that are available for PET studies in neuroscience and oncology. The prospects for developing other new radiotracers for imaging other organ diseases also seem to be promising.
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Affiliation(s)
- Chyng-Yann Shiue
- Department of Radiology, University of Pennsylvania School of Medicine, 1 Silverstein, 3400 Spruce Street, Philadelphia, PA 19104, USA.
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Abstract
The sigma (sigma) receptor and its agonists have been implicated in a myriad of cellular functions, biological processes and diseases. Whereas the precise molecular mechanism(s) of sigma receptors and their involvement in cancer cell biology have not been elucidated, recent work has started to shed some light on these issues. A molecular model has been proposed for the cloned sigma1 receptor; the precise molecular nature of the sigma2 receptor remains unknown. sigma receptors have been found to be frequently up-regulated in human cancer cells and tissues. sigma2 receptor drugs particularly have been shown to have antiproliferative effects. An interesting possibility is that sigma and/or sigma1 drugs could produce anticancerous effects by modulating ion channels. As well as proliferation, a variety of other metastatic cellular behaviors such as adhesion, motility, and secretion may also be affected. Other mechanisms of sigma receptor action may involve interaction with ankyrin and modulation of intracellular Ca(2+) and sphingolipid levels. Although more research is needed to further define the molecular physiology of sigma receptors, their involvement in the cellular pathophysiology of cancer raises the possibility that sigma drugs could be useful as novel therapeutic agents.
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Affiliation(s)
- Ebru Aydar
- Department of Biological Sciences, Sir Alexander Fleming Building, Imperial College, South Kensington Campus, London SW7 2AZ, United Kingdom.
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Zheng QH, Stone KL, Mock BH, Miller KD, Fei X, Liu X, Wang JQ, Glick-Wilson BE, Sledge GW, Hutchins GD. [11C]Choline as a potential PET marker for imaging of breast cancer athymic mice. Nucl Med Biol 2002; 29:803-7. [PMID: 12453589 DOI: 10.1016/s0969-8051(02)00339-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[11C]Choline has been evaluated as a potential positron emission tomography (PET) marker for imaging of breast cancer. The biodistribution of [11C]choline was determined at 45 min post iv injection in MCF-7's transfected with IL-1alpha implanted athymic mice and MDA-MB-435 implanted athymic mice. The results showed the uptake of [11C]choline in these tumors was high, 2.0% dose/g in MCF-7's transfected with IL-1alpha implanted mice and 1.8% dose/g in MDA-MB-435 implanted mice; the ratios of tumor/muscle (T/M) and tumor/blood (T/B) were 1.7 (T/M, MCF-7's), 2.1 (T/M, MDA-MB-435) and 6.9 (T/B, MCF-7's), 12.5 (T/B, MDA-MB-435), respectively; the tumor/muscle ratios are moderate, and the tumor/blood ratios are high. The micro-PET imaging of [11C]choline in both breast cancer athymic mice was acquired for 15 min from a MCF-7's transfected with IL-1alpha and/or MDA-MB-435 implanted mouse at 45 min post iv injection of 1 mCi of the tracer using a dedicated high resolution (<3 mm full-width at half-maximum) small FOV (field-of-view) PET imaging system, Indy-PET II scanner, developed in our laboratory, which showed the uptake of [11C]choline in MCF-7's transfected with IL-1alpha tumor or MDA-MB-435 tumor implanted in a nude athymic mouse. These results suggest that [11C]choline may be a potential PET breast cancer imaging agent.
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Affiliation(s)
- Qi-Huang Zheng
- Department of Radiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Marrazzo A, Prezzavento O, Pappalardo MS, Bousquet E, Iadanza M, Pike VW, Ronsisvalle G. Synthesis of (+)- and (-)-cis-2-[(1-adamantylamino)-methyl]-1-phenylcyclopropane derivatives as high affinity probes for sigma1 and sigma2 binding sites. FARMACO (SOCIETA CHIMICA ITALIANA : 1989) 2002; 57:45-53. [PMID: 11902645 DOI: 10.1016/s0014-827x(01)01170-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Selective ligands for either sigma1 (sigma1) or sigma2 binding sites are potentially useful for gaining a better understanding of the physiological functions of these proteins. Moreover, potent and selective homochiral sigma1 and sigma2 binding site ligands represent leads to potential radioligands for tumour imaging with positron emission tomography (PET). On the basis of their structural similarity to previous leads, new (+)- and (-)-cis-2-[(1-adamantylamino)-methyl]-1-phenylcyclopropane derivatives were synthesised and their binding affinities for sigma1 and sigma2 binding sites were determined. Each enantiomer showed high affinity for both sigma1 and sigma2 binding sites, but only (-)-cis-methyl-2-[[1-adamantyl(methyl)amino]methyl]-1-phenylcyclopropane-carboxylate, (-)-4, showed appreciable selectivity for binding to sigma1 versus sigma2 sites. The enantiomers of cis-(2-[[1-adamantyl(methyl)amino]methyl]-1-phenylcyclopropyl)methanol, 6, expressed the highest affinity for sigma1 and sigma2 binding sites. Ligands (-)-4, (+)-6 and (-)-6 might be rapidly labelled in their N-methyl groups by methylation of the N-desmethyl analogues with [11C]iodomethane to provide prospective radioligands for PET. The N-desmethyl analogues, which are also high affinity ligands, were prepared and shown to undergo satisfactory methylation with iodomethane.
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Affiliation(s)
- Agostino Marrazzo
- Department of Pharmaceutical Sciences, University of Catania, Catana, Italy
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