Apoptogenic activity of ethyl acetate extract of leaves of Memecylon edule on human gastric carcinoma cells via mitochondrial dependent pathway

Objective:To evaluate the anti-proliferative and apoptogenic activity of ethyl acetate extract from the leaves of Memecylon edule(EtAc-LME) in MKN-74,NUGC gastric cancer cells and non cancerous gastric mucous cells(GES-1),and to explore the mechanism of EtAc-LME induced apoptosis.Methods:The mechanism of EtAc-LME induced apoptosis was explored by analysing the activation of pro-caspases,PARP cleavage,expression of cytochrome-c (Cyt-c) was determined by western blotting,mRNA expression of Bcl-2,Bax by RT-PCR,loss of mitochondrial potential using DiOC6 dye,annexin binding assay and its influence on cell cycle arrest by flow cytometry.Results:The results indicated that EtAc-LME inhibited the gastric cancer cell growth in dose-dependent manner and cytotoxicity was more towards the gastric cancer cells(NUCC and MKN-74) compared to normal gastric cells(GES-1),suggesting more specific cytotoxicity to the malignant cells.Over expression of Cyt-c and subsequent activation of caspases-3 and down regulation of Bcl-2 and loss in mitochondrial potential in EtAc-LME treated MKN-74 and NUGC cells suggested that EtAc-LME induced apoptosis by mitochondrial dependent pathway.Conclusions:The present findings suggest that ethyl acetate extract of Memecylon edule induces apoptosis selectively in gastric cancer cells emphasizing the importance of this traditional medicine for its potential in the treatment of gastric cancer.