Influence of Bax on apoptosis and drug sensitivity of HCC-9204 cells

Objective To investigate the role of Ba x in apoptotic pathways and the response of human HCC-9204 cells to cell death induced by adriamycin. Methods The whole length of Bax cDNA was transfected into human hepatocellular car cinoma cell line HCC-9204 by lipofectamine transfection. Expression of Bax in protein was analyzed by immunohistochemistry. TUNEL and flow cytometry were used to assess the effect of Bax on apoptosis. Tetrazolium blue (MTT) assay was used to evaluate drug sensitivity of HCC-9204 cells. Re sults The expression of Bax protein increased in Bax transfected cells at 24~48h after the addition of ZnSO_4. Apoptotic index sig nificantly increased in HCC-9204/Bax cells at 24h and 48h (3.6±5.3 vs 27 .2±10.5, t=63.45, P0.05;4.2±4.1 vs 32.3±8.6, t=93.27, P0.05), respectively. Flow cytometry showed a significant sub-G1 peak an d apoptosis in 15.36% HCC-9204/Bax cells at 48h after treatment. MTT assay showed that the effects of Bax on cell viability following ADR exposure were sig nificant as compared to the vehicle-transfected HCC-9204/pMD cells. Conclusion Overexpression of Bax co uld not only induce apoptosis, but also sensitize HCC-9204 cells to cell death induced by adriamycin.