APOPTOSIS OF HEPATOCARCINOMA CELLS HepG2 INDUCED BY HUAIER EXTRACT THROUGH REGULATION OF HBx and CEACAM1 GENE EXPRESSION

Huaier can effectively inhibit the growth of tumor cells by enhancing the immune system. However, the mechanism of its function is still not clear. The current study aimed to explore the possible mechanism of Huaier in inhibiting human hepatocarcinoma cells by observing its effect on proliferation and invasion in hepatocarcinoma cells, HepG(2) and HepG(2)-X, which stably express the HBx gene, and by comparing the levels of mRNA transcription and protein expression of HBx and CEACAM1 in HepG(2) cells and HepG(2)-X cells when treated with different concentrations of Huaier. HepG(2) cells and HepG(2)-X cells were treated with 0, 1.5, 3.0, and 6.0 g/L-1 Huaier extract in vitro. MTT assay was used to measure the inhibition of cell proliferation. The transwell cell model coated with Matrigel glue was used to detect the invasion of HepG(2) and HepG(2)-X cells in vitro. Flowcytometry was used to observe changes in cell cycle. Real-time PCR and Western blot were used to detect HBx and CEREAM1 mRNA transcription and protein expression separately. Huaier extract can inhibit HepG(2) and HepG(2)-X cell proliferation in a time- and dose-dependent manner. The A value of HepG(2)-X cells in each group was higher than that of HepG(2) cells. Compared with the control group, the invasion ability of HepG(2) and HepG(2)-X cells decreased significantly after treatment with Huaier extract, in a dose-dependent manner. The cell cycle of HepG(2) and HepG(2)-X was arrested at S phase. The distribution of G0/G1 phase decreased gradually with the increase of the concentration of Huaier extract, and the proportion of G0/G1 phase distribution declined. After treating with Huaier extract, mRNA transcription and protein expression of HBx in HepG(2) and HepG(2)-X declined, while those of CEACAM1 increased, reflecting a dose-dependent manner (P<0.05). Therefore, we concluded that the inhibitory effect of Huaier extract on hepatocarcinoma cell proliferation might function through down regulation of HBx gene expression and upregulation of CEACAM1 gene expression.