Protein tyrosine non-receptor type 23 (PTPN23) plays a critical role in signal transduction events involved in cell differentiation, proliferation, adhesion, migration and invasion. PTPN23 deletion has been associated with a number of epithelial cancers but its role in the development of colorectal cancer CRC has not yet been studied. Our preliminary data strongly suggests that PTPN23 controls intestinal epithelial homeostasis and proliferation, and that its loss might promote metastasic behavior of cancer cells. The main aim of this project is to investigate the role of PTPN23 in the development of intestinal cancer and to study how intestinal epithelial cell (IEC)- or immune cell-specific PTPN23 deletion affects IEC/cancer cell proliferation, differentiation, and survival. Further, we will establish how loss of PTPN23 affects the intestinal immune cell landscape, anti-tumor immune responses and the development of intestinal inflammation.