Expression of Cyclooxygenase-2 in Colorectal Cancer and Adenoma

Kim, Jeong Wook; Jung, Gyu; Han, Seong Hyeock; Jeong, Hyun Joo; Do, Jae Hyuk; Chang, Sae Kyung

Abstract

BACKGROUND/AIMS
Several epidemiological and animal studies suggest that the use of nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and sulindac, decreases the risk of colorectal cancer and adenoma. A likely mechanism by NSAIDs is a cyclooxygenase-2 (Cox-2) related inhibition of cell proliferation. The aim of our study was to evaluate the incidence of Cox-2 expression in colorectal carcinoma, as well as adenoma, and its clinicopathologic significance. MERHODS: We investigated the expression of Cox-1 and Cox-2 in 20 colorectal adenomas, 21 colorectal carcinomas and paired normal tissues of large intestine. The levels of Cox-1 and Cox-2 mRNA were determined by reverse transcription-polymerase chain reaction and Digoxigenin-labelled probe.
RESULTS
Cox-1 mRNA was expressed in all examined tissues including the adenomas, carcinomas and paired normal tissues. On the other hand, Cox-2 mRNA was expressed in some colorectal carcinomas (33.3%, 7/21) and adenomas (15.0%, 3/20), but not in paired normal tissues. Cox-2 expression rates in colorectal carcinomas and adenomas were lower in this study than in other previous studies. CONCLUSIONS: The expression rate of Cox-2 mRNA was higher in colorectal adenocarcinoma than in the adenoma and normal mucosa.