Purpose: Osteosarcoma causes extensive human mortality and there is urgent need to develop novel therapies or to identify efficient therapeutic targets for its management. Herein the role and therapeutic potential of miR-17 was explored in osteosarcoma.
Methods: The normal hFOB.19 cell line and the osteosarcoma cell lines SAOS-2, HOS, 143B, T1-73 and mG63 were used in the present study. The expression analysis of miR-17 was carried out by quantitative Real-Time polymerase chain reaction (qRT-PCR). Lipofectamine 2000 reagent (Invitrogen, Carlsbad, CA, USA) was used for transfection. WST-1 assay was used for determination of cell proliferation and autophagy was detected by transmission electron microscopy (TEM). Wound healing and transwell assays were used for the determination of cell migration and invasion. Protein expression was determined by western blot analysis.
Results: The expression of miR-17 was significantly elevated in all the osteosarcoma cells. Suppression of miR-17 resulted in decrease of the viability and colony formation of the SAOS-2 osteosarcoma cells. The inhibition of SAOS-2 cell proliferation upon miR-17 suppression was found to be due to induction of autophagy which was accompanied with enhancement in the expression of LC3B II and Beclin-1. Suppression of miR-17 was also accompanied by inhibition of the SAOS-2 cell migration and invasion. The in silico analysis showed that miR-187 targets PTEN in the SAOS-2 cells. The expression of PTEN was found to be downregulated in all the osteosarcoma cells and suppression of miR-17 expression caused enhancement in the expression of PTEN. Overexpression of miR-17 caused inhibition of the proliferation and colony formation of the SAOS-2 cells. Additionally, silencing of miR-17 could abolish the effects of miR-17 inhibition in the SAOS-2 cells.
Conclusion: MiR-17 may be proven a therapeutic target in the management of osteosarcoma.