A standardized extract from Paeonia lactiflora and Astragalus membranaceus induces apoptosis and inhibits the proliferation, migration and invasion of human hepatoma cell lines

Paeonia lactiflora and Astragalus membranaceus are two traditional Chinese medicines, which are commonly used in Chinese herb prescription to treat liver diseases. The protective effects of the extract prepared from the roots of Paeonia lactiflora and Astragalus membranaceus (PAE) on liver fibrosis have been demonstrated in previous studies. However, its effect on hepatocellular carcinoma (HCC) has not been investigated to date. In this study, the effects of PAE on the apoptosis, proliferation, migration and invasion of the human hepatoma cell lines HepG2 and SMMC-7721 were investigated. Our data demonstrated that treatment with PAE (50-200 mg/l) caused an inhibitory effect on the proliferation of the hepatoma cell lines HepG2 and SMMC-7721. Furthermore, PAE induced apoptosis of HepG2 cells and SMMC-7721 cells, which was demonstrated by PI staining. In addition, immunocytochemistry and western blotting showed that PAE significantly decreased the expression of Bcl-2, while the expression of Bax and cleaved caspase-3 in HepG2 cells and SMMC-7721 cells was significantly increased after treatment with PAE. These results clearly demonstrated that PAE induced hepatoma cell apoptosis through increasing the Bax-to-Bcl-2 ratio and upregulating the activation of caspase-3. In addition, the results of wound healing assay and Matrigel invasion assay showed that PAE displayed inhibitory activity on the migration and invasion of HCC cells. Taken together, the present data provides evidence that PAE is a potent antineoplastic drug candidate for the treatment of HCC.