Antiproliferative Effect of Polysaccharide Fraction of Astragalus Ovinus Against MCF-7 Cancer Cell Line

Background: The effect of Astragalus has been recognized in traditional Chinese medicine, and the roots are believed to have anti-cancer properties. This study investigated the effects of the ethanolic extract and polysaccharide fraction of Astragalus ovinus roots on MCF7 cell line. Methods: We used MTT assay to evaluate the cytotoxicity of A. ovinus roots. The status of cell cycle and apoptosis were examined, using flow cytometry. The gene expressions related to the extrinsic and intrinsic apoptotic pathways (caspases 8 & 9) were also examined by real-time polymerase chain reaction (PCR). Results: The cytotoxicity data showed that the A. ovinus extract inhibited the proliferation of MCF7 cancer cells in a dose-dependent manner. The IC50 of Cisplatin , ethanolic extract and polysaccharides fraction were 22.42, 560.9, and 961.2 in µg/ml, respectively. Also, the cell cycle analysis showed that the ethanolic extract and polysaccharide fractions arrested the cell cycle in the G1 phase. Examination of the apoptotic effects showed that treatment with either the A. ovinus extract or the polysaccharide fraction induced apoptosis in MCF-7 cancer cells. The expression of caspases 8 and 9 genes was inhibited after exposure to either cisplatin or the polysaccharide fraction (PFA). However, treatment with the extract inhibited only the caspase-8 gene expression. Conclusion: The results confirmed that treatment with the extract and polysaccharide fraction caused anti-proliferative effect and apoptosis of MCF-7 cell line. Therefore, it can be concluded that the A. ovinus extract and the polysaccharides have potential therapeutic effects against human breast cancer cells.