MiR-30a regulates the proliferation, migration, and invasion of human osteosarcoma by targeting Runx2

Osteosarcoma (OS) is the most common primary malignant bone tumor in young patients. However, treatment paradigms and survival rates have not improved in decades. MicroRNAs have been shown to be critical regulators of physiological homeostasis and pathological process, including bone disease. Nearly half of the microRNA (miRNA) genes are located at genomic regions and fragile sites known to be frequently deleted or amplified in various kinds of cancers. In this study, we investigated the role miR-30a in OS. A negative correlation between miR-30a expression and malignant grade was observed in OS cell lines. The overexpression of miR-30a reduced proliferation, migration, and invasion in 143B cells and the inhibitor of miR-30a increased proliferation, migration, and invasion in Saos2 cells. Further studies revealed that runt-related transcription factors 2 (Runx2) was a regulative target gene of miR-30a. Rescue assay significantly reversed the effects of overexpressing or inhibiting miR-30a. miR-30a also suppressed tumor formation and pulmonary metastasis in vivo. All the results suggest a critical role of miR-30a in suppressing proliferation, migration, and invasion of OS by targeting Runx2.