Herbal medicine has been utilized to treat a variety of diseases, including cancer. Tetragonia tetragonoides (PALL.) KUNTZE (Aizoaceae) is commonly used in Chinese herbal medicine to treat patients with gastrointestinal disorders, especially in stomach and esophageal cancer. The present study, it is to evaluate the effect of the cytotoxic activity on human heptoma Hep G2 cells form extract of T. tetragonoides. Viability assays for extracts of T. tetragonoides showed that it had dose-dependent effect on Hep G2 human cancer cells. The in-vitro cytotoxic effects were investigated by cell cycle analysis and determination of apoptotic DNA fragmentation in Hep G2 cells. The cell cycle analysis showed that extracts of T. tetragonoides induced a significant increase in the number of cells in G2/M phase. The extract of T. tetragonoides -induced chromatin changes and apoptosis of Hep G2 cells also were confirmed by DAPI and PI staining that were measured by fluorescence microscopy and flow cytometry. These results promoted us to further evaluate apoptosis associated proteins and elucidate the possible signal pathway in Hep G2 cells by the extract of T. tetragonoides.
