In the CRC cell lines HCT-116 and SW480, which express mutated Apc or β-catenin genes, PP (10–100 nM) was found to inhibit the Wnt signaling by interacting with and activating casein kinase 1 alpha (CK1α), which in turn, bound to and phosphorylated β-catenin [55]. This evidence concerns the gene CSNK1A1 and colorectal carcinoma.