Brief Reports
Copyright ©The Author(s) 2005. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 7, 2005; 11(37): 5899-5901
Published online Oct 7, 2005. doi: 10.3748/wjg.v11.i37.5899
Effect of Helicobacter pylori infection on Bax protein expression in patients with gastric precancerous lesions
Hai-Feng Liu, Wei-Wen Liu, Guo-An Wang, Xiao-Chun Teng
Hai-Feng Liu, Department of Gastroenterology, General Hospital of Chinese People’s Armed Police Forces, Beijing 100039, China
Wei-Wen Liu, Guo-An Wang, Xiao-Chun Teng, Department of Gastroenterology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China
Author contributions: All authors contributed equally to the work.
Supported by the fund for Key Projects in the Army Medical and Health 9th 5-year Plan (No. 96Z047), and the Fund for Chongqing Applied Base Research
Correspondence to: Dr. Hai-Feng Liu, Department of Gastroe-nterology, General Hospital of Chinese People’s Armed Police Forces, 69 Yongding Road, Beijing 100039, China. haifengliu333@hotmail.com
Received: November 16, 2004
Revised: February 13, 2005
Accepted: February 18, 2005
Published online: October 7, 2005
Abstract

AIM: To investigate the effect of Helicobacter pylori (H pylori) infection on Bax protein expression, and explore the role of H pylori in gastric carcinogenesis.

METHODS: H pylori was assessed by rapid urease test and Warthin-Starry method, and expression of Bax protein was examined immunohistochemically in 72 patients with pre-malignant lesions.

RESULTS: Bax protein was differently expressed in intestinal metaplasia and gastric dysplasia, and showed 63.99% positivity. The positivity of Bax protein expression in H pylori-positive gastric precancerous lesions (72.3%) was significantly higher than that in H pylori-negative gastric precancerous lesions (48.0%, c2 = 4.191, P < 0.05). H pylori infection was well correlated with the expression of Bax protein in gastric precancerous lesions (r = 0.978, P < 0.01). After eradication of H pylori, the positivity of Bax protein expression significantly decreased in H pylori-positive gastric precancerous lesions (c2 = 5.506, P < 0.05). In the persisting H pylori-infected patients, the positivity of Bax protein expression was not changed.

CONCLUSION: H pylori infection may be involved in the upregulation of Bax gene, which might be one of the mechanisms of H pylori infection-induced gastric epithelial cell apoptosis. H pylori might act as a tumor promoter in the genesis of gastric carcinoma and eradication of H pylori could inhibit gastric carcinogenesis.

Keywords: Helicobacter pylori; Bax protein; Gastric precancerous lesions