Antitumor activity of polysaccharide extracted from Pleurotus ostreatus mycelia against gastric cancer in vitro and in vivo.

The present study aimed to determine the antitumor effects of polysaccharides extracted from Pleurotus ostreatus mycelium on gastric cancer in vitro and in vivo. Polysaccharides were extracted from Pleurotus ostreatus mycelium and an antitumor component, known as Pleurotus ostreatus mycelium polysaccharides 2 (POMP2), with a relative molecular weight of 29 kDa, was then sequentially purified using Sephadex G200 size-exclusion chromatography and diethylaminoethyl-52 cellulose ion-exchange chromatography. The MTT method was used to determine the proliferation of BGC-823 cells treated with POMP2; cell migration assay, colony formation assay and in vivo antitumor tests were used to assess the effect of POMP2 on migration, cell survival and the in vivo tumor formation of BGH-823 cells. Results of the MTT assay indicated that POMP2 had a marked inhibitory effect on the BGC-823 human gastric cancer cell line; when administered at a concentration of 400 mg/l for 72 h, the rate of inhibition was 35.6%. In addition, the colony forming capacity of the BGC-823 cells was significantly reduced following treatment with POMP2. A migration assay indicated that the invasive capabilities of the BGC-823 cells were also significantly inhibited by POMP2. Furthermore, in vivo tests of mice engrafted with BGC-823 cancer cells demonstrated that both tumor weight and volume were markedly reduced following two weeks of treatment with POMP2. The results of the present study suggested that the polysaccharide POMP2 may have a potential application as a natural antitumor treatment for gastric cancer.