NFKB1 and cancer: Despite the comparable ability of bivalent and monovalent IAP antagonists to deplete cIAP1 with subsequent cancer cell death in sensitive cell lines, only bivalent IAP antagonists, such as birinapant, were able to inhibit the TNF-mediated activation of p65/NF-κB, that is, nuclear translocation of p65/NF-κB and the activation of NF-κB promoter-linked luciferase reporter gene (see Figure 1).