The chloroform fraction of guava (Psidium cattleianum sabine) leaf extract inhibits human gastric cancer cell proliferation via induction of apoptosis

The antiproliferative activities of the chloroform fraction (CF) of guava (Psidium cattleianum Sabine) leaf extract were evaluated using several cancer cell lines. Maximum cytotoxicity was observed in SNU-16, a human gastric carcinoma cell line, at concentrations of 50-100 mu g/ml. Flow cytometric analysis demonstrated that CF treatment resulted in a marked accumulation of SNU-16 cells in the sub-G1 phase at concentrations of 100-200 mu g/ml. The induction of apoptosis in SNU-16 cells was confirmed by immunoblotting using antibodies against Bcl-2, Bax, poly (ADP-ribose) polymerase (PARP), caspase-8, and caspase-3. The major CF phytochemicals were identified as ferulic acid, genistein, 3', 4', 5' trimethoxy flavone, phlorizin, and oleanolic acid by high performance liquid chromatography coupled with a photo diode array and electrospray ionisation mass spectrometry (HPLC-PDA-ESI-MS). The results suggest that phytochemicals in the CF of guava (P. cattleianum) leaf extract induce apoptosis in SNU-16 cells. These findings may lead to new strategies for treating human gastric cancer. (C) 2010 Elsevier Ltd All rights reserved.