Background:

Embelin, a natural benzoquinone from plants of the genus Embelia, is an inhibitor of X-linked inhibitor of apoptosis protein (XIAP) with IC50 of 4.1 μM.
XIAP is a member of the inhibitor of apoptosis family of proteins. This protein modulates signaling pathways involved in cell apoptosis and stops cell apoptosis induced by viral infection or overproduction of caspases.
Embelin was shown to exhibit anti-tumor and anti-inflammatory activity in cells. For instance, embelin inhibits cell growth and activates caspases to promote apoptosis in cancer cells with high expression of XIAP [1]. Additionally, embelin was reported to prevent NF-κB activation by inhibiting IKK and thus resulted in suppression of NF-κB-regulated anti-apoptotic and metastatic gene expression [2].
Embelin has also been used extensively in various animal models to study the role of XIAP. In the azoxymethane/dextran sulfate sodium (AOM/DSS) induced colitis-associated cancer (CAC) model, embelin reduced both incidence and tumor size in mice by inhibiting proliferation of tumor epithelial cells and suppressing IL6 expression and IL6-activated STAT3 in vivo [3].
参考文献
1.Nikolovska-Coleska Z, Xu L, Hu Z, Tomita Y, Li P, Roller PP, et al. Discovery of embelin as a cell-permeable, small-molecular weight inhibitor of XIAP through structure-based computational screening of a traditional herbal medicine three-dimensional structure database. J Med Chem 2004,47:2430-2440.
2.Ahn KS, Sethi G, Aggarwal BB. Embelin, an inhibitor of X chromosome-linked inhibitor-of-apoptosis protein, blocks nuclear factor-kappaB (NF-kappaB) signaling pathway leading to suppression of NF-kappaB-regulated antiapoptotic and metastatic gene products. Mol Pharmacol 2007,71:209-219.
3.Dai Y, Jiao H, Teng G, Wang W, Zhang R, Wang Y, et al. Embelin reduces colitis-associated tumorigenesis through limiting IL-6/STAT3 signaling. Mol Cancer Ther 2014,13:1206-1216.