Ovol2 gene inhibits the Epithelial-to-Mesenchymal Transition in lung adenocarcinoma by transcriptionally repressing Twist1

Background: Associated with recent achievements in therapy for advanced lung adenocarcinoma, there will still be an unmet medical need for effective treatment of stage IIIb/IV, and the prognosis of lung cancer is not optimistic till now. Objective: In order to obtain some essential evidences for a potential targeted therapy in lung adenocarcinoma, the effects of Ovol2 gene on Epithelial-to-Mesenchymal Transition (EMT) was observed and the probable mechanisms were analyzed. Methods: Ovol2 expression was previously evaluated by immunochemistry in lung adenocarcinoma tissue, and Ovol2 was overexpressed by lentivirus infection in A549 cells. Subsequently, the migration and invasion ability of A549 cells was tested by Transwell and Wound healing experiments. The mRNA level of genes correlated to EMT was detected by Real-time PCR, and the expression of reasonable makers was probed by Western Blot. Finally, rescue experiment, Luciferase assay, and chromatin immunoprecipitation assay were performed to explore the probable mechanisms. Results: After treated with Ovol2 overexpression, the expression level of E-cadherin was increased, while the expression level of Vimentin and Twist1 was declined not only in the mRNA level but also in the protein level. Moreover, we found that Ovol2 represses transcription of Twist1 by binding to its promoter directly. Wound healing and Transwell assays indicate that the migration and invasion ability were downregulated by Ovol2 in A549 cells. Conclusion: Ovol2 can suppress migration and invasion ability of A549 cells, and prevent EMT by inhibition of Twist1 transcription directly. (C) 2016 Published by Elsevier B.V.