Induction of apoptosis of SW480 human colon cancer cells by (-)-epicatechin isolated from Bulnesia sarmienti

摘要

Background/Aim: (-)-Epicatechin is a major constituent of Bulnesia sarmienti, which is known to possess anticancer properties. Here we report that (-)-epicatechin isolated from B. Sarmienti inhibited growth and induced apoptosis of SW480 human colon cancer cells. Materials and Methods: Cells were treated with different concentrations (0, 25, 50, and 100 μmol/ml) of (-)-epicatechin. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, 40,6-diamidine-20-phenylindole dihydrochloride (DAPI) staining, colony-forming assay, DNA fragmentation analysis, reverse transcription- polymerase chain reaction (RTPCR), annexin V- fluorescein isothiocyanate (FITC) staining, and immunoblot analyses were then carried out. Results: (-)-Epicatechin was found to have cytotoxic activity, and cells treated with this compound had fragmented nuclei, fragmented DNA, and underwent apoptosis. mRNA and protein expression levels of BCL2-associated X protein (BAX) and p53 were up-regulated and those of B-cell lymphoma-2 (BCL2) were down-regulated, while p21 mRNA levels were significantly increased in cells treated with (-)-epicatechin in a concentration-dependent manner. Conclusion: (-)-Epicatechin from B. Sarmienti inhibited colon cancer cell growth and induced apoptosis.