Cucurbitacin E is a plant-derived triterpene that has diverse biological activities. At a concentration of 10 pM, it reduces MPP+-induced death of neuronal PC12 cells through inhibition of autophagy in vitro. Cucurbitacin E inhibits growth of T24 bladder, MDA-MB-468 and MCF-7 breast, PC3 prostate, and colorectal cancer cell lines (IC50s = 50-1,000 nM) through induction of G2/M arrest and apoptosis. It increases bilirubin binding to human serum albumin (HSA) in human plasma in a dose-dependent manner. Cucurbitacin E also inhibits depolymerization of actin filaments isolated from rabbit skeletal muscle actin and in HeLa cells.
