DDB1 and colorectal carcinoma: Furthermore, we found that endogenous UTX protein levels were increased upon depletion of CUL4B in CRC cell line SW620 (Fig. 5B) Additionally, ectopic expression of CUL4B, DDB1 and DET1, the components of the CRL4 complex, reduced UTX expression in a dose-dependent manner (Additional file 5: Fig. S4D-F).