MiR-199a-3p/5p participate in TGF-β and EGF induced EMT in pterygium by targeting DUSP5/MAP3K11
Abstract Background: Recently, it has been reported that miRNA is correlated with pterygium, however its exact mechanism in pterygium is unrevealed and require further investigation. Methods: The differential expression of miRNA in pterygium was profiled using microarray and validated with quantitative real-time PCR (qRT-PCR). Human conjunctival epithelial cells (HCEs) were cultured and treated with TGF-b and EGF. Western blot and immunohistochemistry were carried out to detect epithelial-mesenchymal transition (EMT) markers. Wound healing and transwell assay were used to determine cell migration ability, while apoptosis was determined by flow cytometry. The target genes of miR-199a were confirmed by the dual-luciferase reporter assay. Results: TGF-b and EGF induced EMT in HCEs to mimic the pathogenesis of pterygium. MiR-199a-3p and miR-199a-5p induced EMT in HCEs, whose respectively downstream targets DUSP5 and MAP3K11 hindered EMT in EMT-HCEs in turn. TGF-b and EGF induced EMT promotion and target genes suppression, could be promoted by miR-199a-3p and miR-199a-5p, while impeded by miR-199a-3p and miR-199a-5p inhibitors. The expression levels of miR-199a and target genes were further validated in pterygium tissues, which were consistent the results in cell model. Bioinformatics analysis indicated the miR-199a-3p/5p-DUSP5/MAP3K11 was belong to MAPK signalling pathway in pterygium. Conclusions: TGF-b and EGF probably induced EMT of HCEs through miR-199a-3p/5p-DUSP5/MAP3K11 axis, which explained the pathogenesis of EMT in pterygium and might provide new targets for pterygium prevention and therapy.