title: Uptake of 153Sm-DTPA-bis-biotin and 99mTc-DTPA-bis-biotin in rat as-30D-hepatoma cells.
abstract: Labeled biotin has been used mainly for pretargeted therapy, an approach for increasing the amount of radioactivity delivered to a cancer cell. The aim of this investigation was to prepare (153)Sm-DTPA-bis-biotin and (99m)Tc-DTPA-bis-biotin in order to study their in vitro and in vivo uptake in rat AS-30D hepatoma cells found in ascites and in implanted tumor. DTPA-bis-biotin (pH 8) was (153)Sm labeled with (153)SmCl(3) and (99m)Tc-DTPA-bis-biotin was prepared via SnCl(2) reduction. Radiochemical purity was >98% in both cases. AS-30D hepatoma cells were obtained from ascites of a rat with hepatoma and were propagated in the peritoneum cavity of normal rats. In vitro ascites cell (153)Sm-DTPA-bis-biotin uptake was compared with (153)SmCl(3) cell uptake. The ratio cell (153)Sm-DTPA-bis-biotin/(153) SmCl(3) was 39.6 and when avidin was added it increased to 50. The ratio (99m)Tc-DTPA-bis-biotin/TcO(4)Na was 8.7. Concentration of (153)Sm-DTPA-bis-biotin in tumor 2, 3 and 24 h after administration, was 5, 15 and 3 times higher than in normal muscle (T/nT). Biodistribution in a 0.083-24 h time period showed that (153)Sm-DTPA-bis-biotin was taken up only by ascites tumor cells and hepatoma cells. Two and 3 h ratio ascites/liver (As/Lv) was 6.4 and 6.0. For (99m)Tc-DTPA-bis-biotin 2 and 3 h T/nT was 15.7 and 4.7 and 2 h As/Lv was 1.4. In conclusion, both radiopharmaceuticals show high uptake in rat AS-30D hepatoma cells in ascites and in implanted tumor. Since lung, thyroid, kidney, liver or pancreas carcinomas are ascites producing cancers (153)Sm-DTPA-bis-biotin would be an adequate therapeutic radiopharmaceutical for these patients whose life quality would be enhanced with control of ascites, and a reduction of the primary tumor and its metastases.
authors.affiliation: Servicio de Medicina Nuclear, Hospital de Especialidades, Instituto Mexicano del Seguro Social, Centro Médico Nacional Siglo XXI, Mexico.
authors.forename: Luis
authors.initials: L
authors.lastname: Correa-González
authors.forename: Consuelo
authors.initials: C
authors.lastname: Arteaga de Murphy
authors.forename: Guillermina
authors.initials: G
authors.lastname: Ferro-Flores
authors.forename: Martha
authors.initials: M
authors.lastname: Pedraza-López
authors.forename: Eduardo
authors.initials: E
authors.lastname: Murphy-Stack
authors.forename: Dolores
authors.initials: D
authors.lastname: Mino-León
authors.forename: Graciela
authors.initials: G
authors.lastname: Pérez-Villaseñor
authors.forename: Yaneth
authors.initials: Y
authors.lastname: Díaz-Torres
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Muñóz-Olvera
mesh_terms: D000818:Animals; D001710:Biotin / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D009368:Neoplasm Transplantation; D009928:Organ Specificity; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics*; D004369:Pentetic Acid / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured
chemical_list: C400052:DTPA-bis-biotin; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C478095:technetium 99m DTPA-bisbiotin; D001710:Biotin; D004369:Pentetic Acid