J Korean Soc Coloproctol.  2001 Oct;17(5):259-266.

Expression of Cyclooxygenase-2 in Colorectal Adenocarcinoma

• Kim HS
• Heo TG
• Hong SW
• Joo M
• Jang YG
• Kweon DS
• Paik IW
• Lee H

Abstract

PURPOSE
Several studies indicate that nonsteroidal anti-inflammatory drugs including aspirin and sulindac reduce the risk of colon cancer. Futhermore, nonsteroidal anti-inflammatory drugs that inhibit the cyclooxygenase (COX) are shown to inhibit the development colon cancer in animal models of carcinogenesis. COX-1 is constitutively expressed to fulfill its beneficial housekeeping roles. COX-2 is not constitutively expressed by most normal tissues, but it is rapidly induced by certain inflammatory cytokines, tumor promoters, growth factors and oncogenes. The purpose of this study is to evaluate the role of COX-2 in colorectal carcinoma development and the correlation between COX-2 expression and tumor angiogenesis and p53 overexpression.
METHODS
Immunohistochemical analyses using antibodies against COX-2, factor VIII-related antigen, vascular endothelial growth factor (VEGF) and p53 were carried out on archival specimens of 15 colorectal adenoma and 41 adenocarcinoma.
RESULTS
COX-2 expression was increased in 5/15 (33.3%) adenomas and 24/41 (58.5%) adenocarcinomas. COX-2 expression in adenocarcinoma was nearly significantly higher than in adenoma (P=0.050). In adenocarcinoma, COX-2 expression was increased in early cancer (TNM stage) (P=0.028) and well differentiated tumor (P=0.029). COX- 2 expression was not correlated with VEGF expression, microvessel density and p53 overexpression.
CONCLUSIONS
These findings indicate that enhanced expression of COX-2 occurs early during colorectal cancer progression. However, further investigations are needed to evaluate the relationship of COX-2 and tumor angiogenesis using other laboratory methods.

Keyword

COX-2; Colorectal cancer; Immunohistochemical staining

MeSH Terms

Adenocarcinoma*
Adenoma
Antibodies
Aspirin
Carcinogenesis
Carcinogens
Colonic Neoplasms
Colorectal Neoplasms
Cyclooxygenase 2*
Cytokines
Housekeeping
Intercellular Signaling Peptides and Proteins
Microvessels
Models, Animal
Oncogenes
Prostaglandin-Endoperoxide Synthases
Sulindac
Vascular Endothelial Growth Factor A
von Willebrand Factor
Antibodies
Aspirin
Carcinogens
Cyclooxygenase 2
Cytokines
Intercellular Signaling Peptides and Proteins
Prostaglandin-Endoperoxide Synthases
Sulindac
Vascular Endothelial Growth Factor A
von Willebrand Factor