LncRNA FEZF1-AS1 promotes pulmonary fibrosis via up-regulating EZH2 and targeting miR-200c-3p to regulate the ZEB1 pathway

The role and detailed mechanisms of lncRNAs in idiopathic pulmonary fibrosis (IPF) are not fully understood. qPCR was conducted to verify lncRNA FEZF1-AS1 expression in the transforming growth factor-beta 1 (TGF-β1)-stimulated human lung fibroblasts (HLF) and A549. The EMT-related proteins were performed by western blotting. Cell proliferation, migration, and transition were detected by CCK-8, colony formation, wound-healing and transwell assays. A dual-luciferase reporter assay was conducted to validate the target relationship of FEZF1-AS1 and miR-200c-3p. FEZF1-AS1 is highly expressed in the fibrotic A549 and HLF. in vitro experiments revealed that FEZF1-AS1 facilitates cell proliferation, migration and invasion. Knockdown of FEZF1-AS1 attenuated TGF-b1-induced fibrogenesis both in vitro. Moreover, silencing FEZF1-AS1 inhibited fibrogenesis through modulation of miR-200c-3p. In addition, inhibition of miR-200c-3p promoted fibrogenesis by regulation of Zinc finger E-box binding homeobox 1 (ZEB1). Mechanistically, FEZF1-AS1 promoted lung fibrosis by acting as a competing endogenous RNA (ceRNA) for miR-200c-3p. FEZF1-AS1 silencing increased the expression and activity of miR-200c-3p to inhibit ZEB1 and alleviate lung fibrogenesis in A549 and HLF. In addition, our study showed that FEZF1-AS1 can regulate enhancer of zeste homolog2 (EZH2) to upregulate fibrosis-related proteins and promote lung fibrosis. In summary, the results of our study revealed the pulmonary fibrogenic effect of FEZF1-AS1 in cellular experiments, demonstrating the potential roles and mechanisms of the FEZF1-AS1/miR-200c-3p/ZEB1 and FEZF1-AS1/EZH2 pathways, which provides a novel and potential therapeutic target to lung fibrosis.