Cyclooxgenase-2 Expression in Chronic Inflammatory Bowel Disease:Comparing of Immunohistochemical Stain to Real-time PCR

ABSTRACT

BACKGROUND/AIMS: This study compared the results of cyclooxygenase-2 (COX-2) expression in inflammatory bowel disease and tuberculous colitis as evident by immunochemical staining and real time polymerase chain reaction (PCR). METHODS: Patients with ulcerative colitis (n=18), Crohn's disease (n=7), tuberculous colitis (n=7) and 10 normal controls were included. Biopsied colonic mucosa was simultaneously used for immunohistochemical staining and real time PCR. RESULTS: Patients with inflammatory bowel disease and tuberculous colitis showed high COX-2 expression by both methods compared to the normal controls. In Crohn's disease patients, the real time PCR value correlated well staining grade; this correlation was not evident in ulcerative colitis patients. In real time PCR, grossly normal colonic mucosa in ulcerative colitis also showed higher expression of COX-2 than normal mucosa. CONCLUSIONS: Real time PCR value of COX-2 is more representative of inflammation state in inflammatory bowel disease than the value from immunohistochemical staining.