These collective findings indicate that SPOP contributes to β-catenin ubiquitination and promotes its proteasomal degradation in CRC cells.Since the MATH domain of SPOP binds to β-catenin and the MATH domain recognizes the SBC motif of the substrate proteins [27], we inferred the two SBC motifs of β-catenin and constructed two β-catenin truncation plasmids (SBC1 and SBC2) (Fig. 5E). Here, SPOP is linked to colorectal carcinoma.