[Effect of Helicobacter pylori on gastric epithelial cell kinetics and expression of apoptosis-related proteins in gastric carcinogenesis].
OBJECTIVE
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-X(L) 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.
Lee
Kang Moon
KM
Department of Internal Medicine, College of Medicine, The Catholic University of Korea.
Lee
Dong Soo
DS
Yang
Jin Mo
JM
Ahn
Byung Min
BM
Lee
Eun Hee
EH
Yoo
Jin Young
JY
Kim
You Joung
YJ
Chung
In Sik
IS
Sun
Hee Sik
HS
Park
Doo Ho
DH
D000230:Adenocarcinoma / Q000378:metabolism / Q000382:microbiology; D000236:Adenoma / Q000378:metabolism / Q000382:microbiology; D000328:Adult; D017209:Apoptosis; D002455:Cell Division; D002908:Chronic Disease; D005260:Female; D005753:Gastric Mucosa / Q000737:chemistry / Q000382:microbiology / Q000473:pathology*; D005756:Gastritis / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D016480:Helicobacter pylori; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*; D011518:Proto-Oncogene Proteins / Q000032:analysis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D013274:Stomach Neoplasms / Q000378:metabolism / Q000382:microbiology* / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000032:analysis; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein
C494826:BAX protein, human; C494811:BCL2L1 protein, human; D019394:Ki-67 Antigen; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein