Hyperthermia enhanced chemosensitivity of human malignant glioma cells.

In an effort to overcome chemoresistance of human malignant glioma cells, the modulation of drug-induced cell death by hyperthermia was assessed in 4 human malignant glioma cells lines, LN-18, LN-229, T98G and U87MG. Compared to normothermic conditions, pulsed 24 h drug exposure enhanced the sensitivity of glioma cells most strikingly with teniposide, treosulfan, topotecan and cisplatin, moderately with vincristine, CCNU and doxorubicin, but not with gemcitabine. Susceptibility to hyperthermia-mediated drug sensitization, varied significantly with T98G and LN-229 being strongly sensitized and U87MG being most resistant to the effects of hyperthermia. Hyperthermia did not significantly modulate drug-induced changes in cell cycle distribution. The degree of sensitization was independent of p53 status and of multidrug resistance (mdr) activity. Hyperthermia may thus be a useful approach to overcome, chemoresistance of human malignant glioma cells.