Abstract
The present study aimed to investigate the expression levels of microRNA (miR)‑503 in osteosarcoma (OS), as well as to assess the effects and underlying mechanisms of miR‑503 on cell proliferation, apoptosis, migration and invasion of OS cells. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to determine the expression levels of miR‑503 in OS and adjacent normal bone tissue samples. Proliferation, apoptosis, migration and invasion assays were performed to determine the effects of miR‑503 on OS cells. The expression levels of miR‑503 were significantly decreased in OS tissue samples, as compared with normal tissue samples (P<0.0001). Upregulation of miR‑503 significantly inhibited proliferation and induced cell apoptosis, as compared with the negative controls. The results of the present study also demonstrated that miR‑503 significantly decreased the migration and invasion ability of the OS cells, which may be mediated by the inhibition of fibroblast growth factor 2 (FGF2). In conclusion, the present study demonstrated that expression of miR-503 was involved in the inhibition of cellular proliferation, and induced apoptosis of the OS cells. In addition, miR‑503 was able to inhibit the migration and invasion ability of OS cells, likely via the inhibition of FGF2 expression.