Fig. 6

MEG3 promoted the expression of LAMA4 via sponging miR-30e-3p, and reversed the promoting effect of miR-30e-3p on the proliferation of SKOV3 and OVCAR3 cells. a The binding scheme between MEG3 and miR-30e-3p. The binding sequences were predicted using LncBase Experimental V.2. b The relative expression of MEG3 in healthy and cancerous ovarian tissues. c The relative expression of MEG3 in IOSE80 and HOSEpiC cell lines contrasting to SKOV3, OVCAR3 and Caov-4 cell lines. *P < 0.05, **P < 0.01 vs. IOSE80. d The relative luciferase activity decreased after the 293T cells were co-transfected with miR-30e-3p mimic and pGL3-MEG3-Wt. MEG3-WT + NC, the cells were transfected with pGL3-MEG3-Wt. MEG3-WT + miRNA, the cells were co-transfected with pGL3-MEG3-Wt and miR-30e-3p mimic. MEG3-MU + miRNA, the cells were co-transfected with pGL3-MEG3-Mut and miR-30e-3p mimic. MEG3-MU + NC, the cells were transfected with pGL3-MEG3-Mut. **P < 0.01 vs. MEG3-WT + NC. e MEG3 over-expression plasmid transfection successfully resulted in the significant upregulation of MEG3 in both cell lines, which was reversed by miR-30e-3p mimc. MEG3 over-expression plasmid was constructed using the pcDNA3.1 vector. f, g The mRNA and protein expression of LAMA4 were respectively detected using qRT-PCR and western-blot assay in SKOV3 and OVCAR3 cells with MEG3 over-expression alone or MEG3 over-expression with miR-30e-3p mimic. h The proliferation of SKOV3 and OVCAR3 cells with MEG3 over-expression or MEG3 over-expression with miR-30e-3p mimic using CCK8 assay. OD450 optical density at 450 nm. i A scheme showing the mechanism involving MEG3, miR-30e-3p and LAMA4 in OC. Control group is the blank group. NC, the cells were transfected with empty plasmids. MEG3 OE, the cells were transfected with MEG3 over-expression plasmids. Mimic + MEG3 OE, the cells were co-transfected with miR-30e-3p mimic and MEG3 over-expression plasmids. *P < 0.05, **P < 0.01 vs. Control. ^#P < 0.05, ^##P < 0.01 vs. MEG3 OE group