Effects of quercetin on the apoptosis of the human gastric carcinoma cells

Quercetin, a natural constituent abundantly present in grapes, red wine, and other food products, is known to possess potent antiproliferative effects against various malignant cells. The present study aims to investigate the effect of quercetin on the apoptosis and morphology of gastric carcinoma BGC-823 cells, as well as the probable mechanism, in an effort to identify an effective drug as a potential candidate for gastric cancer. Gastric carcinoma BGC-823 cells were treated with quercetin, and cell morphology was determined by light microscopy and transmission electron microscopy. Apoptosis and cell cycle were measured by flow cytometry, using propidium iodide staining. The apoptotic protein expression of caspase-3, Bcl-2 and Bax was detected by Western blot. Quercetin induced apoptosis in BGC-823 cell. Some morphologic features of apoptosis were found, such as cell shrinkage or even apoptosis body. Quercetin changed the apoptotic protein expression. These results indicate that quercetin can induce apoptosis of the BGC-823 cells. A decrease in Bcl-2/Bax ratio with the increased expression of caspase-3 provides evidence that quercetin-induced apoptosis may be mediated via the mitochondrial pathway. (C) 2011 Elsevier Ltd. All rights reserved.