In the human mammary MDA-MB-231 cancer cells, the premature polyadenylation of MAGI3 produces a truncated protein depleted of PDZ2-PDZ5 (MAGI3pPA, Figure 1) that acts in a dominant-negative manner to prevent full-length MAGI3 from interacting and impairing YAP1 nuclear translocation (Figure 3) [42,90]. This evidence concerns the gene YAP1 and cancer.