[The combined effect of hyperthermia and irradiation on cultured human glioma cell line].

The effects of hyperthermia (HT) and irradiation (RT) on a cultured human glioma cell line (KC) was examined by a colony formation assay and immuno-histochemical methods using monoclonal antibody (MoAb) against bromodeoxyuridine (BrdU) and MoAb Ki-67. The colony formation assay revealed that HT inhibited the cell survival in time and temperature dependent fashion. RT also inhibited the cell survival depending on the irradiation doses. The combination of HT and RT showed an additive effect. The immunohistochemical examination indicated that both HT and RT reduced the BrdU labeling index and Ki-67 positive rate of the surviving cells. HT mainly affected the cells in the S-phase and RT seemed to affect the cells in the G2+ M phase. The combination of HT and RT also showed an additive effect. These results suggest that the combined therapy will be useful in the treatment of malignant gliomas.