Anticancer effect of Lycium barbarum polysaccharides on colon cancer cells involves G0/G1 phase arrest

Colorectal cancer is one of the most common cancers worldwide. The anticancer effect of Wolfberry ( Lycium barbarum ) polysaccharide (LBP) on colon cancer cells is largely unknown. To investigate the growth effect of LBP on human colon cancer cell and its possible mechanisms, human colon cancer SW480 and Caco-2 cells were treated with 100–1,000 mg/l LBP for 1–8 days. Cell growth was measured by MTT assay and crystal violet assay. Distribution of the cell cycle was analyzed by flow cytometry. Western blotting was used to indicate changes in the level of cyclins and cyclin-dependent kinases (CDKs). LBP treatment inhibited both colon cancer cell lines in a dose-dependent manner. At concentrations from 400 to 1,000 mg/l, LBP significantly inhibited the growth of SW480 cells (400 mg/l, P