EFNA4 deletion suppresses the migration, invasion, stemness, and angiogenesis of gastric cancer cells through the inactivation of Pygo2/Wnt signaling.

ABSTRACT

Gastric cancer represents an aggressive malignancy and a leading contributor to cancer death. Ephrin-A4 (EFNA4) has been proposed to be related to the immune microenvironment and prognosis of gastric cancer. This study was undertaken to discuss the participation and mechanism of EFNA4 in the development of gastric cancer. RT-qPCR and western blot examined EFNA4 and Pygopus2 (Pygo2) expression in gastric cancer cells. After transfection of EFNA4 interference plasmids or co-transfection of EFNA4 interference plasmids and Pygo2 overexpression plasmids, cell proliferation was detected by the CCK-8 method and EDU staining. Wound healing, Transwell, TUNEL, and endothelial cell tube formation assays detected cell migration, invasion, apoptosis, and angiogenesis, respectively. Western blot examined the expression of metastasis-, apoptosis-, angiogenesis-, and Wnt signaling-associated proteins. Cell stemness was estimated by the sphere formation assay, RT-qPCR, and western blot. Through the experimental data, it was noticed that EFNA4 expression was increased in gastric cancer cells. Knockdown of EFNA4 suppressed the proliferation, migration, invasion, angiogenesis as well as stemness while aggravating the apoptosis of gastric cancer cells. Also, EFNA4 depletion reduced Pygo2 protein expression and then inactivated Wnt/ß-catenin signaling. Further elevation of Pygo2 reversed the impacts of EFNA4 silencing on Wnt/ß-catenin signaling, cell proliferation, apoptosis, migration, invasion, angiogenesis as well as stemness in gastric cancer. Accordingly, the knockdown of EFNA4 might downregulate Pygo2 and inactivate Wnt/ß-catenin signaling to exert protective effects against gastric cancer.