Unlike in many immune-deficient nude-mice xenograft tumor models in which MLN4924 showed impressive anti-tumor activity by targeting neddylation and CRLs [47–49], MLN4924 had no effect on tumor growth in this immunocompetent syngeneic tumor model, indicating that its immune suppressive activity, as evidenced by induction of PD-L1 and reduction of toxic T cells in tumor tissues, counteracted its regular anti-cancer effect as a neddylation inhibitor [6, 32]. Here, CD274 is linked to cancer.