SENSITIZATION OF HUMAN GLIOBLASTOMA T98G CELLS TO VP16 AND VM26 BY HUMAN TUMOR-NECROSIS-FACTOR

The effect of Tumor Necrosis Factor (TNF) on VP16 or VM26 cytotoxicity was studied in a human glioblastoma cell line T98G, which expresses T NF-receptors. Although T98G cells did not produce TNF endogenously the y were resistant to the cytolytic effect of TNF. T98G cells were also moderately sensitive to the action of VP16 or VM26. TNF given at 1000 U/ml was able to increase the cell drug-sensitivity significantly. Thi s effect was due to an increase in the VP 16-induced cleavable-complex es by TNF. These findings suggest that TNF specifically sensitizes hum an glioma T98G cells to the effects of VP16 of VM26.