TLR4 and cancer: Degradation of IAP proteins alone by an IAP antagonist is not sufficient to kill cancer cells (Figure 1), as we reported (28), but enables LPS to rapidly induce the apoptosis of cancer cells expressing a high level of cIAP1/2 through TLR4- and MyD88-mediated production of TNFα (Figures 3, 4, 6), which causes the cancer cell apoptosis when IAP proteins are degraded by an IAP antagonist (28).