Growth arrest of human gastric adenocarcinoma cells by bioactive compounds of Cordyceps jiangxiensis (CaoMuWang) through induction of apoptosis

Author: Jian-hui Xiao ^{1, 2*}, Dai-xiong Chen ¹, Ning Fang ¹, Zu-lin Liu ¹ and Tao Zhang ¹

Received 25 May 2006, accepted 21 August 2006.

Abstract

Cordyceps fungi are Chinese ethnomedicines and have recently been shown to be effective against certain cancers. In the present study, the growth inhibitory effect of Cordyceps jiangxiensis on human gastric adenocarcinoma cell line SGC-7901 was examined. Both chloroform and methanol extract of C. jiangxiensis were effective in inhibiting gastric cancer cell proliferation in a dose- and time-dependent manner. Chloroform extract of C. jiangxiensis (CECJ) is more potent, with IC50 of 10 µg ml^-¹, as compared to 200 µg ml^-¹ for methanol extract of C. jiangxiensis (MECJ). Flow cytometry analysis indicated that CECJ caused cell cycle arrest at the G2/M phase, similar to taxol. Both CECJ and MECJ induced gastric adenocarcinoma cell apoptosis, as evidenced by Hoechst 33528 staining for chromatin, annexin-V/propidium iodide double staining for early phase cell apoptosis and terminal deoxynucleotidyltransferase dUTP nick end labeling (TUNEL) for late phase cell apoptosis. CECJ was more potent than MECJ in inducing cancer cell apoptosis, comparable to the known anticancer agent taxol. Furthermore, taxol, CECJ and MECJ increased caspase-3 activity in cancer cells. Taken together, the growth inhibitory effect of CECJ on gastric adenocarcinoma cells is associated with induction of apoptotic cell death, at least in part through caspase-3 activation. CECJ may thus have therapeutic potential in the treatment of human gastric cancers.