Characterization and study on the anti-breast cancer activity of polysaccharides from red ginseng

Red ginseng polysaccharide (RGP) has increasingly attracted attention in the field of anti-tumor, due to its ability to directly kill tumor cells and improve the immune function. Nevertheless, studies on RGP of its extraction, purification, structural characterization, and activity of anti-breast cancer are still inadequate. In this research, the polysaccharide was extracted from red ginseng, purified and named RGP-45. Results indicated that the yield, relative molecular weight and total sugar content of RGP-45 are 12.59%, 27.8 kDa and 91.57%, respectively. RGP-45 is linked by α-type pyranose, and its main component, mass ratio are as follows: glucose (44.9%), glucuronic acid (34.6%), galactose (9.5%), galacturonic acid (6.8%) and arabinose (4.3%). RGP-45 could significantly inhibit the proliferation of 4T1 cells, promote the apoptosis of 4T1 cells and block 4T1 cells in the G0/G1 phase. These effects were accompanied by the up-regulation expression of Bax and down-regulation expression of Bcl-2. In vivo, the tumor growth of 4T1 breast cancer mice was inhibited by RGP-45 of 150 mg/kg. When combined with cisplatin, RGP-45 could effectively alleviate the inflammatory injury of liver and lung tissues. Meanwhile, RGP-45 could reduce the level of IL-10 in serum of tumor-bearing mice, up-regulate the expression of p53 and Bax, and down-regulate the expression of Bcl-2 in tumor of breast cancer mice. As mentioned above, RGP-45 showed good anti-breast cancer activity in vitro and in vivo. Therefore, RGP-45 possesses the potential to be used as a candidate for the treatment of breast cancer in the future.