title: Potentiation of chemotherapy cytotoxicity following iododeoxyuridine incorporation in Chinese hamster cells.
abstract: This study reports on the potentiation of selected chemotherapy drugs following halogenated pyrimidine incorporation into cellular DNA. Exponentially growing cultures of Chinese hamster V79 cells were exposed to 10(-5) M IdUrd or BrdUrd for 17 hr (approximately 2 cell doublings). This exposure resulted in approximately 16% replacement of thymidine by IdUrd or BrdUrd in the cellular DNA. Following the IdUrd exposure, dose response curves were determined for a 1 hr exposure to the various drugs. IdUrd pre-treatment was shown to enhance the cytotoxicity of melphalan, adriamycin, cisplatin, and neocarzinostatin with enhancement ratios at 1% survival of 1.5, 1.8, 1.5, and 1.4 respectively. BrdUrd pre-treatment also enhanced cisplatin cytotoxicity. A combination of BrdUrd pretreatment, cisplatin, and X rays was shown to yield additive survival effects. These findings are discussed in the context of possible clinical application of local drug perfusion of tumor-containing organs.
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001973:Bromodeoxyuridine / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D006224:Cricetinae; D004247:DNA / Q000378:metabolism; D004357:Drug Synergism; D007065:Idoxuridine / Q000378:metabolism / Q000494:pharmacology*; D066298:In Vitro Techniques
chemical_list: D000970:Antineoplastic Agents; D004247:DNA; D001973:Bromodeoxyuridine; D007065:Idoxuridine