Hence, inactivation of SAG either by siRNA silencing of itself [11, 38], or by overexpression of its upstream E3 ligase, NEDD4-1 (this study), or by its small molecule inhibitor, MLN4924 [39], all induces apoptosis, further supporting the notion that SAG E3 ligase is an attractive anti-cancer target. Here, NEDD4 is linked to cancer.