MicroRNA-100 inhibits osteosarcoma cell proliferation by targeting Cyr61

Increasing evidence indicates that microRNAs (miRNAs) participate in almost every step of cellular processes and are often aberrantly expressed in human cancer. Therefore, the discovery of miRNAs may provide a new and powerful tool for understanding the mechanism and treatment of carcinogenesis. The aim of this study was to investigate the functional significance of miR-100 and to identify its possible target genes in osteosarcoma (OS) cells. Here, we found that expression level of miR-100 was significantly decreased in osteosarcoma tissues in comparison with the adjacent normal tissues. The enforced expression of miR-100 was able to inhibit cell proliferation in Saos-2 and MG63 cells, while its antisense oligonucleotides (antisense miR-100) promoted cell proliferation. Moreover, our results further revealed that expression of Cyr61, an extracellular matrix-associated growth factor, was negatively regulated by miR-100. Therefore, we consider that miR-100 acts as a tumor suppressor for osteosarcoma. It may provide novel diagnostic and therapeutic options for human osteosarcoma in the future.