Correlation between expression of cyclooxygenase-2 and angiogenesis in human gastric adenocarcinoma.
OBJECTIVE
To evaluate the expression of cyclooxygenase (COX-2) and the relationship with tumor angiogenesis and advancement in gastric adenocarcinoma.


METHODS
Immunohistochemical stain was used for detecting the expression of COX-2 in 45 resected specimens of gastric adenocarcinoma; the monoclonal antibody against CD34 was used for displaying vascular endothelial cells, and microvascular density (MVD) was detected by counting of CD34-positive vascular endothelial cells. Paracancerous tissues were examined as control.


RESULTS
Immunohistological staining with COX-2-specific polyclonal antibody showed cytoplasmic staining in the cancer cells, some atypical hyperplasia and intestinal metaplasia,as well as angiogenic vasculature present within the tumors and prexisting vasculature adjacent to cancer lesions. The rate of expression of COX-2 and MVD index in gastric cancers were significantly increased, compared with those in the paracancerous tissues (77.78 vs 33.33 %, 58.13+/-19.99 vs 24.02+/-10.28, P<0.01, P<0.05, respectively). In 36 gastric carcinoma specimens with lymph node metastasis, the rate of COX-2 expression and MVD were higher than those in the specimens without metostasis (86.11 vs 44.44 %, 58.60+/-18.24 vs 43.54+/-15.05, P<0.05, P<0.05, respectively). The rate of COX-2 expression and MVD in the specimens with invasive serosa were significantly higher than those in the specimens without invasion to serosa (87.88 vs 50.0 %, 57.01+/-18.79 vs 42.35+/-14.65, P<0.05, P<0.05). Moreover, MVD in COX-2-positive specimens was higher than that in COX-2-negative specimens (61.29+/-14.31 vs 45.38+/-12.42,P<0.05). COX-2 expression was positively correlated with MVD (r=0.63, P<0.05).


CONCLUSIONS
COX-2 expression might correlate with the occurance and advancement of gastric carcinoma and is involved in tumor angiogenesis in gastric carcinoma. It is likely that COX-2 by inducing angiogenesis can be one of mechanisms which promotes invasion and metastasis of gastric carcinoma. It may become a new therapeutic target for anti-angiogenesis.
Li
Hong-Xia
HX
Department of Gastroenterology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China. hx1105sina.com
Chang
Xin-Ming
XM
Song
Zheng-Jun
ZJ
He
Shui-Xiang
SX
D000230:Adenocarcinoma / Q000098:blood supply* / Q000473:pathology / Q000601:surgery; D051546:Cyclooxygenase 2; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism*; D008565:Membrane Proteins; D008833:Microcirculation / Q000473:pathology*; D009389:Neovascularization, Pathologic / Q000473:pathology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000098:blood supply* / Q000473:pathology / Q000601:surgery
D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases