Embelin induces apoptosis through down-regulation of XIAP in human leukemia cells.

The present study was undertaken to determine the molecular mechanisms by which embelin induces apoptosis in human leukemia cells. Embelin resulted in loss of cell viability and inhibition of proliferation in a dose- and time-dependent manner, which was largely attributed to apoptosis. Embelin caused depolarization of mitochondrial membrane potential. Western blot analysis showed that the expression of anti-apoptotic proteins X-linked inhibitor of apoptosis (XIAP) was down-regulated by embelin. Embelin induced activation of caspase-9 and embelin-induced apoptosis was prevented by caspase inhibitors. Taken together, these findings suggest that embelin results in human leukemia cells apoptosis through caspase-dependent mechanisms involving down-regulation of XIAP.