ZEB2 promotes tumor metastasis and correlates with poor prognosis of human colorectal cancer.

Colorectal cancer remains the most common cause of cancer-related deaths worldwide and it continues to lack an effective treatment. Here, we found that zinc finger E-box binding homeobox 2 (ZEB2) was overexpressed in several colorectal cancer cell lines and colorectal cancer specimens relative to adjacent non-cancerous tissues. Although ZEB2 has been reported to be associated with several tumors, its involvement in colorectal cancer progression remains unclear. In this study, we investigated the biological functions and molecular mechanisms of ZEB2 underlying colorectal carcinoma metastasis and angiogenesis. HCT116 colorectal cancer cells were treated with ZEB2 shRNA or recombinant ZEB2, and the expression of ZEB2 was assessed using reverse transcriptase polymerase chain reaction (RT-PCR) and immunoblotting, respectively. Ectopic expression of ZEB2 induced proliferation and epithelial-mesenchymal transition (EMT), and increased the metastatic capacity of HCT116 cells in vitro and in vivo. Furthermore, endothelial cell tube formation and angiogenesis in chick embryo chorioallantoic membrane (CAM) were accelerated by conditioned medium from ZEB2-overexpressing HCT116 cells. Further, overexpression of ZEB2 accelerated tumor growth and angiogenesis in xenotransplantation models. However, silencing endogenous ZEB2 caused an opposite outcome. Our results provide new evidence that ZEB2 promotes the progression of colon cancer, and thereby might represent a novel therapeutic target for colorectal carcinoma.