Abstract: AIM: To study the effects and mechanism of Lycium barbarum polysaccharide on the proliferation and apoptosis of osteosarcoma HOS cells. METHODS: Osteosarcoma HOS cells were divided into four groups: control group, LBP-I group, LBP-II group and LBP-III group. MTT was used to detect cell proliferation; PI single staining was used to detect cell cycle; Annexin V-FITC/PI double staining was used to detect apoptosis; Western blot was used to detect the expression of Cleaved Caspase-3, Cleaved PARP, cyclin-dependent kinase 4 (CDK4), cyclin D1, Shh and Gli1. Shh signal activator and Lycium barbarum polysaccharide treated osteosarcoma HOS cells together; the changes of cell proliferation, cell cycle and apoptosis were observed. RESULTS: Compared with the control group, the proliferation ability of LBP-I group, LBP-II group and LBP-III group decreased, the proportion of cells in G0/G1 phase increased[(51.2±4.1)% vs. (59.1±3.2)%, (66.8±2.0)%, (72.3±3.2)%, F=72.76, P<0.001], the level of apoptosis increased[(3.9±0.3)% vs. (13.2±1.2)%, (17.6±1.3)%, (24.8±2.1)%, F=364.50, P<0.001], the expression levels of Cleaved Caspase-3, Cleaved PARP protein increased, the expression levels of CDK4, cyclin D1, Shh and Gli1 decreased (P<0.05). Compared with cells not treated with Shh signal activator, the cells treated with Shh signal activator could reverse the effect of Lycium barbarum polysaccharide on the proliferation, cycle arrest and apoptosis of osteosarcoma HOS cells. CONCLUSION: Lycium barbarum polysaccharides blocked the cell cycle of osteosarcoma HOS cells, inhibited cell proliferation and promoted cell apoptosis by inhibiting Shh signaling pathway.

Key words: lycium barbarum polysaccharide, osteosarcoma, Sonic Hedgehog signal, apoptosis