Gambogic acid induces the apoptosis and autophagic cell death in human hepatoma cells / 肿瘤研究与临床

ABSTRACT

Objective To study the effect of gambogic acid on apoptosis and autophagy in human hepatoma cells HepG2, and to detect its possible mechanism. Methods After exposure of HepG2 cells to gambogic acid at different concentration for 24 h, cell proliferation rates was determined by MTT assay, apoptosis rate was detected by the flow cytometry (FCM), formation of autophagic vacuoles was observed by the monodansyl cadaverine (MDC) fluorescence staining, expression level of apoptosis-related proteins Bax, bcl-2 and autophagy related protein Beclin 1 was detected by Western blot. Results HepG2 cell growth was inhibited by the gambogic acid dose dependence. After exposure to gambogic acid at 0, 2.0, 4.0 and 8.0 μmol/L for 24 h, cell apoptosis rate was significantly increased to 5.31 %, 29.18 %, 31.50 % and 46.09 %(P <0.05), MDC average fluorescence intensity was also significantly increased to 6.3 ±1.1, 82.6 ±4.5, 132.9±15.7 and 157.7±9.0 (P<0.01). Western blot showed that gambogic acid could promote the expression of apoptosis protein Bax (0.17 ±0.02, 0.75 ±0.06, 0.78 ±0.05, 0.89 ±0.10, P <0.05), and decrease the expression of anti-apoptosis protein bcl-2 (1.18 ±0.04, 0.90 ±0.06, 0.64 ±0.08, 0.57 ±0.05, P <0.05), meanwhile, it could also increase the expression of autophagy related protein Beclin (0.67±0.03, 0.92±0.04, 0.95±0.07, 1.04±0.06, P<0.05). Conclusion Gambogic acid can inhibit the growth of human hepatoma HepG2 cells by inducing apoptosis and autophagic cell death.