Tumor Necrosis Factor-?? Induces p53-dependent Apoptosis in Rat Glioma Cells

IN THIS STUDY, we demonstrated that tumor necrosis factor (TNF)-α inhibited the viability of rat glioma (C6) cells and induced apoptosis but did not affect the viability of rat newborn brain, mainly astroglial cells. The antitumor activity of TNF-α against C6 cells was partially inhibited by actinomycin D and cycloheximide, suggesting that it is possibly dependent upon new ribonucleic acid and protein synthesis. The results of immunoblotting assay demonstrated that TNF-α decreased the expression of mutant p53 protein but induced the expression of wild-type p53 in C6 cells during apoptosis. We suggest that TNF-α may activate the function of wild-type p53 protein by the suppression of mutant p53, at least indirectly, and induce p53-dependent apoptosis in glioma cells.