miR-522 stimulates TGF-β/Smad signaling pathway and promotes osteosarcoma tumorigenesis by targeting PPM1A.

Osteosarcoma (OS) is identified as an aggressive malignancy of the skeletal system and normally occurs among young people. It is well accepted that microRNAs are implicated in biological activities of diverse tumors. Although miR-522 has been proved to elicit oncogenic properties in a wide range of human cancers, the physiological function and latent mechanism of miR-522 in OS tumorigenesis remain largely to be probed. In the current study, we certified that miR-522 was highly expressed in OS cells and presented carcinogenic function by contributing to cell proliferation, migration, and EMT progression whereas dampening cell apoptosis. In addition, miR-522 provoked TGF-β/Smad pathway through targeting PPM1A. Finally, the results of mechanism experiments elucidated that miR-522 stimulated TGF-β/Smad pathway to induce the development of OS via targeting PPM1A, which exposed that miR-522 may become a promising curative target for OS patients.