Intestinal epithelial SNAI1 promotes the occurrence of colorectal cancer by enhancing EMT and Wnt/β-catenin signaling

Colorectal cancer (CRC) is a prevalent cause of cancer and mortality on a global scale. SNAI1, a member of the zinc finger transcription superfamily, is a significant contributor to embryonic development and carcinogenesis through the process of epithelial–mesenchymal transition (EMT). While prior research utilizing CRC cells and clinical data has demonstrated that SNAI1 facilitates CRC progression through diverse mechanisms, the precise manner in which epithelial SNAI1 regulates CRC development in vivo remains unclear. In this study, colitis and colitis-associated CRC were induced through the use of intestinal epithelium-specific Snai1 knockout (Snai1 cKO) mice. Our findings indicate that Snai1 cKO mice exhibit a reduced susceptibility to acute colitis and colitis-associated CRC compared to control mice. Western-blot analysis of colon tissues revealed that Snai1 cKO mice exhibited a higher overall apoptosis level during tumor formation than control mice. No significant differences were observed in the activation of the classical p53 signaling pathway. However, Snai1 cKO mice exhibited weakened EMT and Wnt/β-catenin pathway activation. In summary, our study has provided evidence in vivo that the intestinal epithelial SNAI1 protein suppresses apoptosis, amplifies the EMT, and activates the Wnt/β-catenin signaling pathways in both early and late phases of CRC formation, thus promoting the development and progression of colitis-associated CRC.