Thermosensitization by methylglyoxal bis(guanylhydrazone) in Chinese hamster cells.
The modification of methylglyoxal bis(guanylhydrazone) (MGBG) by 42 degrees C hyperthermia-and/or radiation-induced cell killing was examined in Chinese hamster V-79 cells. At concentrations of more than 10 microM, cell survival decreased exponentially with increased MGBG exposure times. Cell lethality of MGBG (10 microM) was not specific for cell-cycle phases tested from G1/S through G2. When cells were treated with MGBG (10 microM) for 6 hr and then exposed to 42 degrees C hyperthermia with or without a 24-hr interval, cell survival decreased markedly compared with that for 42 degrees C alone. Cells became thermosensitive after MGBG treatment. Cells exposed to MGBG (10 microM) for 6 hr before or after X irradiation were slightly radiosensitive. When X irradiation was combined with MGBG and 42 degrees C hyperthermia, cells became more radiosensitive. From these results, it is suggested that MGBG may change the intracellular state to sensitize cells to the cytotoxic action(s) of hyperthermia.
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D006146:Guanidines / Q000494:pharmacology*; D006918:Hydroxyurea / Q000494:pharmacology; D006979:Hyperthermia, Induced; D008935:Mitoguazone / Q000494:pharmacology*; D011836:Radiation Tolerance; D013997:Time Factors
D006146:Guanidines; D008935:Mitoguazone; D006918:Hydroxyurea