title: Effect of drug exposure duration and sequencing on hyperthermic potentiation of mitomycin-C and cisplatin.
abstract: The effects of drug exposure duration and of heat and drug sequencing on hyperthermic potentiation of mitomycin-C (MMC) and cisplatin (DDP) were studied. Heating for 1 h at 42 degrees C was combined with drug exposure times of 1, 2, 4, or 8 h. For both DDP and MMC, hyperthermic potentiation was greatest when heating was done during drug exposure. Dose enhancement ratios for both drugs at 1% survival were highest with the shortest drug exposure times and decreased as the drug exposure time increased from 1 to 8 h. For DDP, the dose enhancement ratio decreased from 1.9 with a 1-h drug exposure to 1.2 with an 8-h drug exposure. For MMC, the dose enhancement ratio decreased from 1.8 to 1.5 as the drug exposure duration was increased from 1 to 8 h. Our results suggest that thermochemotherapy in vivo is likely to be most effective with rapid infusions of DDP or MMC.
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects*; D002945:Cisplatin / Q000008:administration & dosage*; D006224:Cricetinae; D004334:Drug Administration Schedule; D004357:Drug Synergism; D006358:Hot Temperature; D016685:Mitomycin; D008937:Mitomycins / Q000008:administration & dosage*
chemical_list: D008937:Mitomycins; D016685:Mitomycin; D002945:Cisplatin