Induction of apoptosis and cell cycle arrest in glioma cells by GL331 (a topoisomerase II inhibitor)

Background: GL331 is a topoisomerase II inhibitor and, in this study, the effects of GL331 upon rat C6 glioma cells were investigated. Materials and Methods: The glioma cells were treated with GL331, then a cytotoxicity assay was done to evaluate the cytotoxic effects of GL331 and flow-activated cell sorter analysis was performed to analyze the cellular apoptosis and cell cycle distribution of the glioma cells. The expressions of p53, p21 and 14-3-3σ in glioma cells treated with GL331 were investigated by Western blot analysis. Results: GL331 was demonstrated to exert cytotoxic effects upon and induce apoptosis of the C6 glioma cells in a concentration- and time-dependent manner (p < 0.05). GL331 also caused the glioma cells to accumulate in the G2/M-phase of the cell cycle and increased the expressions of p53, p21 and 14-3-3σ. Conclusion: GL331 exerts cytotoxic effects and induces apoptosis in C6 glioma cells, accompanied by cell accumulation in the G2/M-phase and activation of p53, p21 and 14-3-3σ.