Abstract: Objective To explore the role of phospholipase C-γ1(PLC-γ1) in tumor necrosis factor-α(TNF-α)-induced apoptosis of human glioma SWO cells.Methods The PLC-γ1 pathway was blocked by U73122 in SWO cells,and the inhibitory effect of TNF-α on SWO glioma cell proliferation with or without U73122 treatment was investigated by MTT assay.The cell apoptosis induced by TNF-α along or in combination with U73122 was detected by flow cytometry with PI staining.The expression of caspase-3 and Bcl-2 was detected by Western blotting.Results and Conclusion U73122 can sensitize SWO glioma cells to TNF-α-induced apoptosis.Blocking the PLC-γ1 pathway may not induce apoptosis of SWO glioma cells,but can sensitize SWO glioma cells to small-dose TNF-α-induced apoptosis,the mechanism of which may involve down-regulation of bcl-2.