Cyclooxygenase-2 Expression in Bile Duct Cancer / 한국간담췌외과학회지

ABSTRACT

PURPOSE: Epidemiological studies have shown that regular ingestion of a nonsteroidal anti-inflammatory drug reduces the risk of fatality from colon cancer. Cyclooxygenase-2 (COX-2) has been found to be overexpressed in various types of tumor, including colorectal cancer. It has been suggested that the COX-2 enzyme may play an important role in carcinogenesis and tumor progression. The aims of this study were to find the relationship between COX-2 expression and bile duct carcinogenesis and its clinical significance in bile duct cancer. METHODS: The COX-2 expression was determined using three methods, reverse transcription polymerase chain reaction (RT-PCR), Western blotting and immunohistochemical staining. mRNA and proteins were extracted from the tissue specimens of 22 bile duct cancer patients. RESULTS: RT-PCR and western blotting found COX-2 expressions in all the cancers and their paired noncancerous tissues. Immunohistochemistry revealed the highest levels of COX-2 expressed in bile duct carcinoma cells, mainly in the cytoplasm, and a weak reactivity of the COX-2 protein was observed in noncancerous bile duct epithelial cells. CONCLUSION: Based on this study, it is postulated that the carcinogenesis mechanism of COX-2 expression may be initiated from a noncancerous condition, such as chronic inflammation, and may advance to bile duct cancer progression.