Expression of COX-2 proteins in gastric mucosal lesions.
OBJECTIVE
To investigate the expression of COX-2 proteins in gastric mucosal lesions and to assess the relationship between COX-2 expression and type, pathologic stage, differentiation, or lymph node metastasis in gastric cancer and the relationship between COX-2 expression and H pylori infection in gastric mucosal lesions.


METHODS
Thirty patients with gastric carcinoma underwent surgical resection. Samples were taken from tumor site and paracancerous tissues, and ABC immunohistochemical staining was used to detect the expression of COX-2 proteins. H pylori was determined by rapid urea test combined with pathological stating/14C urea breath test.


RESULTS
The positive rate and staining intensity of mutant COX-2 gene expression in gastric cancer were significantly higher than those in paracancerous tissues (66.7% vs 26.7%) (P<0.01, P<0.001). There was a significant correlation between COX-2 and pathologic stage or lymph node metastasis type of gastric carcinoma (76.0% vs 20.0%, 79.2% vs 16.7%) (P<0.05). No correlation was found between COX-2 expression and type or grade of differentiation (P>0.05). COX-2 expression of intestinal metaplasia (IM) or dysplasia (DYS) with positive H pylori was significantly higher than that with negative H pylori (50.6% vs 18.1%, 60.0% vs 33.3%) (P<0.05).


CONCLUSIONS
COX-2 overexpression was found in a large proportion of gastric cancer tissues compared with matched non-cancerous tissues and was significantly associated with advanced tumor stage and lymph node metastasis. Overexpression of COX-2 plays an important role in tumor progression of gastric cancer. COX-2 may also play a role in the early development/promotion of gastric carcinoma and is associated with H pylori infection.
Yu
Lian-Zhen
LZ
Department of Gastroenterology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.
Gao
Heng-Jun
HJ
Bai
Jian-Feng
JF
Sun
Gu
G
Zhao
Han-Lin
HL
Sun
Liang
L
Miu
Kun
K
Zhao
Zhi-Quan
ZQ
D002454:Cell Differentiation; D051546:Cyclooxygenase 2; D005753:Gastric Mucosa / Q000201:enzymology* / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000378:metabolism* / Q000473:pathology; D016480:Helicobacter pylori; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism*; D008207:Lymphatic Metastasis; D008565:Membrane Proteins; D009367:Neoplasm Staging; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000556:secondary
D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases