Interestingly, while acting in cancer cells as a KAP1 stabilizing factor, in untransformed IMR90 and BJ1 cells, SMURF2 showed a negative impact on KAP1 expression (Figure 4A–D), the phenomenon that was also observed in certain Smurf2KO tissues (Figure 4E–G). This evidence concerns the gene SMURF2 and cancer.