Interaction of hyperthermia and cytotoxic agents

Chinese hamster V79 cells in culture were used to investigate the temperature dependence of the cytotoxic action of 4 widely used chemotherapy agents, i.e., adriamycin, bleomycin, cis-platinum(II) diamminedichloride, and N-(phosphonacetyl)-L-aspartate. Cells were exposed to graded doses of each drug for 1 hour at a range of temperatures. Bleomycin showed the largest temperature dependence and N-(phosphonacetyl)-L-aspartate the least, with adriamycin and cis-platinum(II) diamminedichloride between the two extremes. The results presented demonstrated significant differences in the cytotoxicities of chemotherapy agents and their interactions with heat. The idea of combining localized hyperthermia with some chemotherapy agents allowed a targeting of the chemotherapy not otherwise possible.