Relationship between expression and distribution of cyclooxygenase-2 and bcl-2 in human gastric adenocarcinoma.
OBJECTIVE
To explore expression and distribution features of COX-2 and bcl-2 in human gastric adenocarcinoma tissues and to study its biological significance.


METHODS
Totally 36 human gastric carcinoma samples were enrolled in this study (cardiac adenocarcinoma 16 cases, distal gastric adenocarcinoma 20 cases). The expressions of COX-2 and bcl-2 in cancerous tissues and corresponding para-cancerous tissues were investigated by immunohistochemistry using COX-2 polyclonal antibody and bcl-2 monoclonal antibody. The normal gastric mucosa tissues were used as control.


RESULTS
The expressions of COX-2 and bcl-2 in gastric carcinoma were significantly higher than that in the para-cancerous tissues (77.8% vs 47.2%, P<0.01, 80.56% vs 58.33%, P<0.05). The expression of COX-2 in cardiac adenocarcinoma was remarkably higher than that in the distal gastric carcinoma (93.8% vs 65.0%, P<0.01). The expression of COX-2 was mainly localized in the cytoplasm of tumor cells and partly in the nucleus. There is a transition of the COX-2 cytoplasmic positivity to nucleic in tumor cells with the increase of gastric carcinoma pathological grade. Interstitial macrophages, fibroblasts and vascular endothelial cells also expressed COX-2. The tissues with higher expression of COX-2 also expressed high level of bcl-2 protein.


CONCLUSIONS
Abnormal expression pattern of COX-2 within the tissues of human gastric cancer is correlated with tumor location and lymph node metastasis. COX-2 may regulate expression of apoptosis suppressor gene (bcl-2) through interaction of tumor cells and stromal cells and play an important role in the generation and development of tumors, which will be of great help in developing new methods for antitumor therapy.
Chen
Xiao-Li
XL
Department of Pathology, Second Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China. chenxiaoli64.student@sina.com
Su
Bao-Shan
BS
Sun
Run-Qin
RQ
Zhang
Jun
J
Wang
Yi-Li
YL
D000230:Adenocarcinoma / Q000378:metabolism* / Q000556:secondary; D051546:Cyclooxygenase 2; D005753:Gastric Mucosa / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008207:Lymphatic Metastasis; D008565:Membrane Proteins; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology
D008565:Membrane Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases