SMAD6 and colorectal cancer: For example, hsa-miR-425-5p may promote tumor occurrence and metastasis by activating CTNND1 related pathway (Liu et al., 2020), hsa-miR-186-5p regulates TGFβ signaling pathway through expression suppression of SMAD7 and SMAD6 genes in colorectal cancer (Bayat et al., 2021).