For instance, AXIN2 and DKK1 are direct targets and feedback inhibitors of the Wnt pathway in normal cells, whereas their inhibitory effect on activated Wnt signaling in CRC cells is invalid, and instead they become the promoters of CRC metastasis by activating epithelial–mesenchymal transition (EMT) pathways (12). Here, DKK1 is linked to colorectal carcinoma.