SOX2 and neoplasm: In conclusion, our findings demonstrate that miR-126 acts as a tumor suppressor in OS through targeting Sox2. Re-introduction of miR-126 in MG-63 cells can down-regulate Sox2, which dampens cell growth, inhibits cell migration and invasion, and induces cell apoptosis, however, all these activities could be suppressed through over-expression of Sox2. Collectively, this finding not only furthers our understanding of the molecular mechanisms of OS carcinogenesis, but also provides a strong rationale to further investigate miR-126 as a potential biomarker and therapeutic target for OS.