EphA5 knockdown enhances the invasion and migration ability of esophageal squamous cell carcinoma via epithelial-mesenchymal transition through activating Wnt/β-catenin pathway

Abstract

Background: The erythropoietin-producing hepatocellular (Eph) receptor A5 (EphA5) has been found to be overexpressed in some malignant tumors and is associated with disease prognosis. However, the role of EphA5 in esophageal squamous cell carcinoma (ESCC) is not clear. Methods: In the present study, we measured the expression of EphA5 in ESCC tissues and cell lines including KYSE150 and KYSE450 cells. siRNA transfection was used to interfere with EphA5 expression in ESCC cell lines. Cell viability, colony formation, scratch and invasion assays were performed to explore the roles of EphA5 in ESCC cell lines. Flow cytometry analysis was performed to investigate whether EphA5 could affect the cell apoptosis and cycle. The biomarkers related to epithelial-mesenchymal transition (EMT) and molecules associated with Wnt/β catenin signaling were also measured by western blot and immunofluorescence. Results: The protein and mRNA expression of EphA5 were significantly higher in fresh ESCC tissues and cell lines compared with normal control groups and human normal esophageal epithelial cells (HEEC). The cell viability assay and colony formation assay revealed that EphA5 knockdown enhanced the proliferation of KYSE150 and KYSE450 cells in vitro. The invasion and migration of ESCC cells were accelerated after EphA5 knockdown. The expression of EMT biomarkers was altered in ESCC cells transfected with siRNA targeting EphA5. Moreover, EphA5 downregulation enhanced the protein levels of β catenin and p-GSK-3βSer9, which play a key role in the Wnt/β catenin pathway. Conclusions: EphA5 knockdown promotes the proliferation of esophageal squamous cell carcinoma,enhances invasion and migration ability via epithelial-mesenchymal transition through activating Wnt/β catenin pathway.