Antranik H. Shahinian

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UNLABELLED Overexpression of gastrin-releasing peptide (GRP) receptor (GRPR) in both androgen-dependent (AD) and androgen-independent (AI) human neoplastic prostate tissues provides an attractive target for prostate cancer imaging and therapy. The goal of this study was to develop (64)Cu-radiolabeled GRP analogs for PET imaging of GRPR expression in(More)
The predictive utility of several biochemical parameters of 5fluorouracil (5-FUra) action was evaluated in four murine coIonic adenocarcinomas: 5-FUra-sensitive Tumor 38 and 5FUra-resistant Tumors 07/A, 51, and 06/A. Thymidylate synthetase (TS) was determined by a tritiated 5-fluoro-2'-deoxyuridylate (FdUMP)-binding assay. Bolus 5-FUra (80 mg/kg, i.p.)(More)
The predictive utility of several biochemical parameters of 5-fluorouracil (5-FUra) action was evaluated in four murine colonic adenocarcinomas: 5-FUra-sensitive Tumor 38 and 5-FUra-resistant Tumors 07/A, 51 and 06/A. Thymidylate synthetase (TS) was determined by a tritiated 5-fluoro-2'-deoxyuridylate (FdUMP)-binding assay. Bolus 5-FUra (80 mg/kg, i.p.)(More)
The thymidine analog 2'-fluoro-5-methyl-1-beta-D-arabinofuranosyluracil (FMAU) is incorporated into DNA and is resistant to catabolism. We performed pharmacokinetic measurements with [(14)C]FMAU and PET studies with [(11)C]FMAU using rats bearing several different syngeneic tumors. Among normal tissues, FMAU uptake reflected relative cell turnover rates.(More)
A method for determination of levels of incorporation of nonradiolabeled 5-fluorouracil (FUra) into RNA (F-RNA) in tissue samples is shown to be applicable to tissues in vivo. BDF1 mice bearing L1210 ascites cells were injected intraperitoneally with [14C]FUra, 100 mg/kg. The time course of F-RNA levels in L1210 cells was determined by following the(More)
2'-Fluoro-5-[(14)C]-methyl-1-beta-D-arabinofuranosyluracil (FMAU) is an analog of thymidine (TdR) that is resistant to catabolism, is incorporated into DNA, and has been labeled with (11)C for use with positron emission tomography. We compared the uptake and metabolism of [(14)C]FMAU with that of [(3)H]TdR in fast- and slow-growing cell lines of a rat(More)
We hypothesized that the glucose metabolism of prostate cancer is modulated by androgen. We performed in vivo biodistribution and imaging studies of [F-18] fluorodeoxyglucose (FDG) accumulation in androgen-sensitive (CWR-22) and androgen-independent (PC-3) human prostate cancer xenografts implanted in castrated and noncastrated male athymic mice. The growth(More)
The purpose of this study was to investigate the effects of castration and tracer uptake time interval on the level of radiolabeled choline accumulation in murine-implanted human prostate tumor xenografts using quantitative autoradiography. We implanted androgen-dependent (CWR22) and androgen-independent (PC3) human prostate cancer cells in castrated (n =(More)
The competitive basis and specificity of deoxyuridylate (dUMP)-mediated decreases in thymidylate synthase-5'-fluorodeoxyuridylate-folate (TS-FdUMP-folate) ternary complex formation at low concentrations of folates were investigated using charcoal isolation of protein-bound [3H]FuUMP ligand. Reaction conditions used 0.02 microM TS (Lactobacillus casei) and(More)
INTRODUCTION Many fluorinated analogues of adenosine nucleoside have been synthesized and studied as potential antitumor and antiviral agents. Earlier, we reported radiosynthesis of 2'-deoxy-2'-[(18)F]fluoro-1-beta-D-arabinofuranosyl-adenine ([(18)F]-FAA) and 3'-deoxy-3'-[(18)F]fluoro-1-beta-d-xylofuranosyl-adenine ([(18)F]FXA). Now, we report their in vivo(More)