DKK1 and colorectal carcinoma: To further validate the association between tumor budding and wnt beta catenin signaling, we analyzed the expression of positive regulators (CK1 and wnt5a) and the negative regulator (DKK1) of wnt beta catenin signaling in CRC tissues (n = 84) by immunohistochemistry (IHC) staining (Fig. 6E, Supplementary Figure S3 and Table S2).The results revealed significant elevation of CK1 and wnt5a in high-grade tumor budding tissues compared with low-grade tumor budding tissues, while DKK1 was highly expressed in low tumor budding group.