miR-628-5p promotes growth and migration of osteosarcoma by targeting IFI44L

This study investigated the role of miR-628-5p and interferon-induced protein 44-like (IFI44L) in osteosarcoma (OS) and determined whether miR-628-5p modulated OS growth by regulating IFI44L. Based on the data downloaded from Gene Expression Omnibus (GEO) database, we revealed that the expression of IFI44L was downregulated in OS and low expression of IFI44L was correlated with better prognosis of patients with OS. Biological prediction of its upstream regulatory miRNAs on the miRWalk website found that miR-628-5p is a possible upstream regulatory miRNA of IFI44L. Luciferase activity assay demonstrated that miR-628-5p could bind to the 3' untranslated region (UTR) of IFI44L, which proved the above prediction. The expression of miR-628-5p is upregulated in OS and high expression of miR-628-5p is correlated with poor prognosis of patients with OS. The results of RT-qPCR showed that the expression of miR-628-5p in MG-63, U2OS, Saos-2, and SW1353 cells was significantly higher than that in the hFOB1.19 cells. Downregulation of miR-628-5p by miR-628-5p inhibitor significantly inhibited the proliferation, migration, and invasion of MG-63 cells. By rescue assay, we found that knockdown of IFI44L rescued the proliferation and motility of miR-628-5p depleted MG-63 cells. Collectively, our present data illustrated that miR-628-5p promoted the growth and motility of OS at least partly by targeting IFI44L. Moreover, miR-628-5p and IFI44L might be proposed as promising biomarkers in OS diagnosis and treatment.