[CAS NO. 481-42-5]  Plumbagin

Plumbagin exhibits cell proliferation inhibition by inducing cells to undergo G2-M arrest and autophagic cell death. Blockade of the cell cycle is associated with increased p21/WAF1 expression and Chk2 activation, and reduced amounts of cyclin B1, cyclin A, Cdc2, and Cdc25C. Plumbagin also reduces Cdc2 function by increasing the association of p21/WAF1/Cdc2 complex and the levels of inactivated phospho-Cdc2 and phospho-Cdc25C by Chk2 activation. Plumbagin triggers autophagic cell death but not pre-dominantly apoptosis. It inhibits survival signaling through the phosphatidylinositol 3-kinase/AKT signaling pathway by blocking the activation of AK Tand downstream targets, including the mammalian target of rapamycin, forkhead transcription factors, and glycogen synthase kinase 3B. Phosphorylation of both of mammalian target of rapamycin downstream targets, p70 ribosomal protein S6 kinase and 4E-BP1, are also diminished.