Cyclooxygenase-2 expression in colorectal adenomas.

Abstract

Cyclooxygenase-2 is an important target for nonsteroidal anti-inflammatory drugs in suppressing colorectal tumorigenesis. To evaluate the role of cyclooxygenase-2 in sporadic colorectal adenoma, we correlated cyclooxygenase-2 expression in adenomas with other adenoma characteristics. Cyclooxygenase-2 expression was evaluated immunohistochemically in 95 endoscopically resected colorectal adenomas. Cyclooxygenase-2 was expressed mainly in the cytoplasm of adenoma cells, where it was seen in 74 percent (70/95) of adenomas. Expression was related significantly to grade of dysplasia (P < 0.001) and tumor size (P = 0.028). Multivariate logistic regression analysis showed cyclooxygenase-2 expression in adenoma cells to be independently associated with grade of dysplasia (P = 0.001). Observed associations suggest that cyclooxygenase-2 plays an important role in progression of the adenoma-to-carcinoma sequence.