Effect of miR-505 on proliferation and metastasis of osteosarcoma cells and its related mechanisms

Abstract:

Objective：To investigate the effect of miR-505 on proliferation and metastasis of osteosarcoma cells and its mechanisms. Methods：The miR-505 level in human osteoblast of hFOB1.19 and osteosarcoma of cell MG63 was determined by q-PCR. The miR-505 mimics group and the negative control group（miR-NC） were set. Both miR-505 mimics and miR-NC were transfected into MG63 cells with Lipofectamine TM 2000 and cell proliferation rate and invasive cells were compared between two groups. Proteins and mRNA levels of MMP-9，CDK4，Cyclin-D1，HMGB-1，β-catenin and GSK-3β in MG63 cells transfected with miR-505 was further detected via Western blot and q-PCR technologies. Results：The expression level of miR-505 in osteosarcoma cell of MG63 was 0.57±0.06，which was significantly lower than that of 1.03±0.12 in human osteoblast of hFOB1.19（P<0.01）. After transfecting miR-505，expression level in the miR-505 mimics group was 3.59±0.37，which was significantly higher than that of 1.09±0.12 in the miR-NC group（P<0.01）. After transfecting 48 h and 72 h，A450 nm values in the miR-505 mimics group were 0.84±0.09 and 1.29±0.13，respectively，which were significantly lower than those in the miR-NC group（P<0.05）. Invasive cells in the miR-505 mimics group was （42.84±4.35），which was significantly lower than that of （66.84±6.85） in miR-NC group（P<0.05）. Protein lev－els of MMP-9，CDK4，Cyclin-D1 and HMGB-1 in the miR-505 mimics group were lower than those in the miR-NC group（P<0.05）. The mRNA levels of MMP-9，CDK4，Cyclin-D1 and HMGB-1 in the miR-505 mimics group were lower than those in the miR-NC group（P<0.05）. Meanwhile，protein and gene expressions of β-catenin and GSK-3β in Wnt signaling pathway in the miR-505 mim－ics group were significantly lower than those in the miR-NC group（P<0.05）. Conclusion：The miR-505 can down-regulate the expres－sion of MMP-9，CDK4，Cyclin-D1 and HMGB-1 by inhibiting Wnt signaling pathway，so as to inhibit the proliferation and metastasis of osteosarcoma cells.