Inhibition of enhancer of zeste homolog 2 prevents corneal myofibroblast transformation in vitro

Purpose: Corneal fibroblast can be transformed into corneal myofibroblasts by TGF-131. Enhancer of zeste homolog 2 (EZH2) upregulation has been observed in the occurrence of other fibrotic disorders. We investigated the role of EZH2 in the progression of corneal fibrosis and the antifibrotic effect of EZH2 inhibition in corneal fibroblasts (CFs). Methods: Primary CFs were isolated from corneal limbi and the CFs were treated with TGF-131 to induce fibrosis. EPZ-6438 and EZH2 siRNA were used to inhibit EZH2 expression. Myofibroblast activation and extracellular matrix (ECM) protein synthesis was detected by quantitative real-time PCR, western blotting, and immunofluorescence staining assay. The functions of myofibroblast were evaluated by cell migration and collagen gel contraction assays. Molecular mechanisms involved in EZH2 inhibition were investigated by RNA sequencing. Results: TGF-131 activated EZH2 expression in CFs. Treatment with EPZ-6438 (5 mu M) and EZH2 siRNA considerably suppressed corneal myofibroblast activation and ECM protein synthesis in CFs induced by TGF-131 when compared to the control group. EPZ-6438 (5 mu M) suppressed cell migration and gel contraction in CFs. RNA sequencing results revealed that antifibrotic genes were activated after EZH2 inhibition to suppress corneal myofibroblast activation. Conclusion: Inhibition of EZH2 suppresses corneal myofibroblast activation and ECM protein synthesis, and could serve as a novel therapeutic target for preventing corneal scarring.

Automated summary

The study demonstrated that the inhibition of EZH2 effectively suppresses corneal fibrosis induced by TGF-131, including reducing myofibroblast activation and ECM protein synthesis, as well as inhibiting cell migration and gel contraction. RNA sequencing analysis revealed that antifibrotic genes were activated after EZH2 inhibition, leading to the suppression of corneal myofibroblast activation.