Study on gallic acid induced human hepatoma SMMC-7721 cells apoptosis and its mechanism

Aim To investigate the proliferative effect and the apoptosis of human hepatoma SMMC-7721 cells induced by gallic acid( GA),and its underlying mechanism. Methods SMMC-7721 cells were cultured in vitro. MTT assay was used to observe the proliferation of SMMC-7721 cells induced on GA 24,48, 72 h. The morphological and ultra structural changes of the SMMC-7721 cells were observed by inverted microscope and transmission electron microscope respectively. Annexin V-FITC / PI staining was used to quantify the percentages of apoptosis in the total cell population. The expression of p53 mRNA was investigated by RT-PCR. Western blot was used to determine the protein expression of p53. Results GA( 6. 25 ~ 50 μmol ·L- 1) markedly inhibited the activity of proliferation and induced apoptosis of SMMC-7721 cells after 48h in a dose-dependent manner. GA significantly induced cell nuclear condensation and fragmentation. RT-PCR and Western blot results showed that GA could improve the expression of p53 mRNA and protein. Conclusion GA can inhibit the proliferation of human hepatoma SMMC-7721 cells and induce cells apoptosis. The mechanism may be associated with improving tumor suppressor gene p53 expression.