Abstract
MicroRNAs (miRNAs) perform important roles in the development and progression of human malignancy. miR-874, as a tumor suppressor, is decreased in malignant tumors, including osteosarcoma. However, the potential mechanism of miR-874 in osteosarcoma remains largely unknown. In the present study, a dual-luciferase reporter system supported cyclin-dependent kinase 9 (CDK9) as a direct target gene of miR-874. miR-874 mimics evidently repressed CDK9 expression in osteosarcoma. Furthermore, osteosarcoma tissues and cell lines exhibited increased expression of CDK9, and CDK9 expression levels were inversely correlated (R=-0.725) with that of miR-874 in osteosarcoma tissues. Finally, CDK9 overexpression reversed the potential effect of miR-874 on the proliferation and invasion of osteosarcoma cells. Overall, the results revealed that miR-874, as a tumor suppressor, is involved in osteosarcoma progression and metastasis by targeting CDK9, indicating that the miR-874/CDK9 pathway may serve as a potential therapeutic target for the treatment of osteosarcoma.