Fig. 6. MiR-342-3p modulates osteosarcoma (OS) characteristics by targeting FOSL2. (A) Prediction of potential binding sites between miR-342-3p and FOSL2 on Targetscan Human. (B) Luciferase reporter assay was performed to determine the luciferase activity of 293T cells transfected with miR-342-3p mimics/miR-NC mimic (miR-342-3p/NC) and FOSL2-wt/FOSL2-mut. (C) RNA immunoprecipitation was conducted to determine FOSL2 expressions in MG-63 cell samples. (D and E) Determination of FOSL2 expression both at the mRNA level and protein level in MG-63 cells after transfection with miR-342-3p/NC, anti-miR-342-3p/anti-NC. Restoration of FOSL2 in U2OS and MG-63 cells was induced by co-transfection with miR-342-3p mimic and empty plasmid (Vector), and defective FOSL2 restoration was obtained by incubation of miR-342-3p mimic and FOSL2 overexpression plasmid (FOSL2). (F and G) qPCR detected FOSL2 mRNA expression in OS tissues and cell lines. (H) Cell proliferation was assessed by cell activity with MTT staining. (I) Cell apoptosis was detected with flow cytometry. (J) Activity of caspase 3 was measured using western blotting. (K) Cell migration was determined using Transwell assay. GAPDH was the loading control. (L) Cell invasion was determined using Transwell assay. (M) Positive cells of GFP-LC3 were calculated. (N) Expressions of Beclin 1, LC3-I and LC3-II were detected with western blotting. GAPDH was the loading control. All experiments were carried out in triplicate. ^*p<0.05.