IAP Antagonists Selectively Eliminate Therapy-Induced Senescent Cancer Cells via TNFα-Independent Apoptosis. (PubMed, Cancer Sci)
Here, we show that AZD5582 and AT406, potent antagonists of cellular inhibitor of apoptosis proteins 1 and 2 (cIAP1 and cIAP2) and X-linked inhibitor of apoptosis protein (XIAP), selectively eliminated HCT116 and RKO cells that had undergone senescence following treatment with a chemotherapeutic agent such as trifluridine, camptothecin, or doxorubicin. At physiological concentrations, TNFα sensitized non-senescent, proliferating cancer cells, but not TIS and nutlin-3a-induced senescent cancer cells, to apoptosis in the presence of IAP antagonists. Collectively, these findings suggest that IAP antagonists could serve as effective concomitant agents to TIS-inducing chemotherapy that promotes TNFα secretion within tumors, functioning not only as TNFα-independent senolytics but also as potentiators of TNFα-mediated apoptosis in adjacent non-senescent, proliferating cancer cells.