Korean J Gastroenterol.  2003 Jul;42(1):12-19.

Effect of Helicobacter pylori on Gastric Epithelial Cell Kinetics and Expression of Apoptosis-related Proteins in Gastric Carcinogenesis

• Lee KM
• Lee DS
• Yang JM
• Ahn BM
• Lee EH
• Yoo JY
• Kim YJ
• Chung IS
• Sun HS
• Park DH

Abstract

BACKGROUND/AIMS: We investigated apoptosis, cell proliferation and the expression of apoptosis-related proteins in the gastric epithelial cells of Helicobacter pylori (H. pylori)-negative and positive patients. METHODS: TUNEL staining, immunohistochemical staining for Ki-67, p53, Bcl-2, Bcl-XL and Bax were performed on paraffin-embedded specimens obtained from 11 H. pylori-negative controls, 20 H. pylori-positive chronic gastritis, 10 chronic gastritis with intestinal metaplasia (IM), 11 adenoma, and 7 adenocarcinoma patients. Apoptosis and proliferation were expressed as apoptosis index (AI) and proliferation index (PI). RESULTS: In H. pylori-positive groups, apoptosis and proliferation were increased compared with controls. However, an AI/PI ratio was highest in chronic gastritis cases and then gradually reduced according to the progress from IM to cancer. p53 was expressed in 28.6% of adenocarcinoma cases. Expression of Bax was significantly increased in chronic gastritis and IM patients compared with controls. CONCLUSIONS: H. pylori infection induces marked increase in apoptosis and proliferation of gastric mucosa. In the premalignant lesions, the balance between apoptosis and proliferation is altered, and this imbalance may play a key role in the gastric carcinogenesis.

Keyword

Helicobacter pylori; Apoptosis; Gastric carcinogenesis; Protein p53; Bax

MeSH Terms

Adenocarcinoma/metabolism/microbiology
Adenoma/metabolism/microbiology
Adult
*Apoptosis
Cell Division
Chronic Disease
Female
Gastric Mucosa/chemistry/microbiology/*pathology
Gastritis/microbiology/pathology
Helicobacter Infections/complications/metabolism/*pathology
*Helicobacter pylori
Humans
Immunohistochemistry
In Situ Nick-End Labeling
Ki-67 Antigen/analysis
Male
Middle Aged
Precancerous Conditions/metabolism/microbiology/*pathology
Proto-Oncogene Proteins/analysis
Proto-Oncogene Proteins c-bcl-2/analysis
Stomach Neoplasms/metabolism/*microbiology/pathology
Tumor Suppressor Protein p53/analysis
bcl-2-Associated X Protein
bcl-X Protein