CSNK1A1 and neoplasm: Furthermore, conditional knock-out of CK1α in the intestinal epithelium leads to activation of p53 and Wnt-signaling, while in p53 deficient gut, loss of heterozygosity of the CK1α gene causes a highly invasive carcinoma, indicating that CK1α acts as a tumor suppressor when p53 is inactivated (336).