Our data indicated that the caspase-9 inhibitor ZVAD completely blocked apoptosis induced by PI3K inhibitor, and suggested that AKT conferred resistance to LY294002-induced apoptosis ultimately through suppressing caspase activation pathways in CNE-2Z cells. The results of specific caspase inhibitor demonstrated that blocking caspase-9 pathway exerted a much greater protective effect against apoptosis. Conclusion In summary, Akt played a critical role in regulating the sensitivity of CNE-2Z cells to the induction of apoptosis by LY294002. This kinase pathway conferred resistance by suppressing caspase-9

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