Hsa_circ_0000285 functions as a competitive endogenous RNA to promote osteosarcoma progression by sponging hsa-miRNA-599

Circular RNA (circRNA) is important in the pathogenesis of many diseases. By analyzing the GSE96964 microarray, hsa_circ_0000285 (circ-0000285) was found to be highly expressed in osteosarcoma. Recent studies have shown that circ-0000285 is capable of regulating proliferative and migratory potentials. Here, we investigated the potential functions in regulating osteosarcoma cells to proliferate and migrate. First of all, qRT-PCR data revealed a higher level of circ-0000285 in osteosarcoma cell lines relative to normal osteoblasts. Through dual-luciferase reporter gene assay and RIP assay, we confirmed that both circ-0000285 and TGFB2 could directly bind to miRNA-599. Regulatory effects of circ-0000285 and miRNA-599 on proliferative and migratory potentials were evaluated by EdU assay and transwell migration assay. It is indicated that circ-0000285 overexpression enhanced the proliferative and migratory potentials of osteosarcoma, which could be reversed by miRNA-599 overexpression. This study revealed a vital role of circ-0000285/miRNA-599/TGFB2 axis in regulating the progression of osteosarcoma, providing a novel perspective for clarifying its pathogenesis.