MicroRNA-744 promotes proliferation of osteosarcoma cells by targeting PTEN

Abstract

Micrornas (mirnas/mirs) are non-coding rnas that regulate protein synthesis by targeting mrnas for translational repression or degradation. Previous studies have reported that aberrant expression of mir-744 may be involved in human osteosarcoma; however, the underlying mechanisms remain elusive. in the present study, the expression levels of mir-744 and its downstream signals were determined by reverse transcription-quantitative Pcr and western blotting. cell proliferation was assessed using the bromodeoxyuridine assay, and the target of mir-744 was investigated using a dual-luciferase activity assay. The present study identified a significant upregulation of mir-744 in osteosarcoma tissues compared with adjacent non-tumor tissues. Furthermore, it was demonstrated that ectopic overexpression of mir-744 induced by a mir-744 precursor significantly enhanced proliferation of the osteosarcoma cell line MG63, whereas opposite results were observed following suppression of mir-744 with its inhibitor. Moreover, as a unique anti-oncogene, PTEN was identified as a direct target of miR-744. It was confirmed that miR-744 downregulated PTen expression in MG63 cells by targeting the PTen 3'untranslated region, and that the downstream aKT signal was also regulated by mir-744. collectively, the present results suggested that mir-744 promoted proliferation of human osteosarcoma cells by directly regulating the PTen/aKT signaling pathway.