An Antioxidant Polysaccharide from Ganoderma lucidum Induces Apoptotic Activity in Breast Cancer Cell Line

The purpose of this study is to elucidate the apoptotic activity of Ganoderma lucidum polysaccharide (GLP) in a human breast cancer cell line MCF-7 in vitro. According to DPPH assay, GLP showed a good antioxidant (IC50 value is 202.4 g/mL). Based on MTT assay, the results showed that GLP inhibits MCF-7 cells proliferation in a dose- and time-dependent manner (p<0.001). IC50 values of the cytotoxicity of GLP and doxorubin were 110.907 g/mL and 58.206 g/mL respectively. The results from the flow cytometry indicated that GLP could induce apoptotic activity through inducing the up-regulation of the Bax and Caspase-9 and the down-regulation of the BcL-2 in MCF-7 cells. At 2xIC50, GLP increased the early-apoptotic and dead cells of MCF-7 from 18.23% to 34.76% and 8.45% to16.34% respectively. In conclusion, the GLP shows anticancer activity against MCF-7 through preventing the proliferation and inducing the apoptosis of MCF-7 cells. Our data provide the potential molecular targets in cancer prevention and reveal the key barriers in the current anticancer drugs development.