IBD patients have an increased risk of developing colorectal cancer, however, the immune cells and cytokines that mediate the transition from intestinal inflammation to cancer are poorly understood. Mucosal IL-33 is increased in UC patients, in addition, IL-33 and its receptor, ST2, are expressed in polyps in AOM/DSS models of colitis-associated cancer. Therefore, several studies have implicated IL-33, which is also an important activator of Innate Lymphoid Cells type 2 (ILC2s), in the formation of tumors.