MiR-218 suppresses osteosarcoma proliferation by down-regulating BMI1

Osteosarcoma is the most frequent cancer of primary bone tissue and is associated with a high metastatic potential and poor prognosis. However, the molecular mechanisms underlying osteosarcoma progression are not well defined. MicroRNAs play important roles in cancer development and could serve as therapeutic targets. Although miR-218 has been reported to inhibit the tumorigenesis of some cancers, its role in osteosarcoma remains poorly defined. Here, we investigated the effects of miR-218 overexpression in osteosarcoma cell lines, finding that it severely suppresses the proliferation and tumorigenesis of these human cancer derived cells. Moreover, miR-218 silencing promoted the proliferation and tumorigenesis of osteosarcoma cells lines. Furthermore, BMI1 was found to be a direct target of miR-218 in human osteosarcoma. Collectively, these findings suggest that exogenous over-expression of miR-218 may be an effective therapeutic strategy for osteosarcoma treatment.