MicroRNA-320 inhibits osteosarcoma cells proliferation by directly targeting fatty acid synthase.

Increasing evidence has demonstrated that small noncoding microRNAs (miRNAs) could contribute to cancer development and progression. Besides, they are differentially expressed in human tumor tissues. In the current study, we found that miR-320 was significantly downregulated in human osteosarcoma tissues, compared with adjacent normal tissues. Introduction of miR-320 mimics into U2OS and MG63 cells inhibited cell proliferation, while cell apoptosis rate remained unaltered. Additionally, miR-320 overexpression could also suppress tumor growth in the nude mice. At the molecular level, our results further revealed that the expression of fatty acid synthase (FASN), a key enzyme for de novo biosynthesis of fatty acids, was negatively regulated by miR-320. Therefore, our results suggest that miR-320 may act as a tumor suppressor for osteosarcoma.