In vitro modulation of adriamycin and mitoxantrone cytotoxicity by hyperthermia and diazepam, in human chronic myeloid leukemia cells.

Adriamycin and mitoxantrone are known antitumor agents. The use of these agents is limited by their toxicity to normal body tissue. This paper shows that it is possible to achieve greater log cell-kill by using these drugs in combination with hyperthermia and diazepam. Experiments were carried out on 22 human chronic myeloid leukemia samples. 10 micrograms/ml adriamycin and 1 microgram/ml mitoxantrone were used in combination with hyperthermia 42 degrees C, for 3 h and 1 h respectively, with and without diazepam (1 microgram/ml). Inhibition of incorporation of radiolabeled nucleic acid precursor (3H-thymidine) in treated cells as compared to the untreated cells was used as a measure of cytotoxicity. The statistical evaluation of the data shows that the enhancement of drug cytotoxicity due to hyperthermia and diazepam is highly significant (p less than 0.001) in case of both the drugs.