Antitumor Activity of Triterpenoid Saponin-Rich Adisia gigantifolia Extract on Human Breast Adenocarcinoma Cells in Vitro and in Vivo

The aim of this study was to explore whether the ethanolic extract of Ardisia gigantifolia rhizomes (AGB-5), a traditional herbal medicine from China, could affect the proliferation of human breast adenocarcinoma (MCF-7) cells in vitro and to explore the antitumor effects of AGB-5 in BALB/c mice engrafted with MCF-7 cells. The results showed that AGB-5 markedly inhibited the proliferation of MCF-7 cells with an IC50 value of 11.89±1.12 µg/mL, increased the S phase and decreased the G2/M phase without influence on G1 phase. MCF-7 cells treated with AGB-5 presented a dose-dependent increase of apoptosis compared with the control group. AGB-5 also significantly increased the activity of caspase-3 and -9 in a dose-dependent manner in MCF-7 cells. Furthermore, in an in vivo model, AGB-5 reduced tumor volume, brought back the red blood cell (RBC) and white blood cell (WBC) count near to normal value, enhanced superoxide dismutase and catalase level of MCF-7 bearing mice. This is the first study to verify the antitumor activity of A. gigantifolia in vivo. The results suggest that AGB-5 may have potential beneficial effects against human breast adenocarcinoma.