Expression of cyclooxygenase-2 in chronic hepatitis B and the effects of anti-viral therapy
Article first published online: 18 JAN 2002
Alimentary Pharmacology & Therapeutics
Volume 16, Issue 2, pages 251–260, February 2002
How to Cite
Cheng, A. S. L., Chan, H. L. Y., Leung, N. W. Y., Liew, C. T., To, K. F., Lai, P. B. S. and Sung, J. J. Y. (2002), Expression of cyclooxygenase-2 in chronic hepatitis B and the effects of anti-viral therapy. Alimentary Pharmacology & Therapeutics, 16: 251–260. doi: 10.1046/j.1365-2036.2002.01163.x
- Issue published online: 18 JAN 2002
- Article first published online: 18 JAN 2002
Cyclooxygenase-2 may play a role in the development of hepatocellular carcinoma, but the relationship between cyclooxygenase-2 and chronic hepatitis B is unknown.
To investigate the expression and cellular localization of cyclooxygenase-2 in chronic hepatitis B patients and the effects of anti-viral therapy.
Using immunohistochemistry, in situ hybridization, Western blot and reverse transcription polymerase chain reaction, protein and messenger RNA expression and cellular localization of cyclooxygenase-2 in 35 chronic hepatitis B patients were assessed. Fourteen histologically normal and non-viral-infected livers were used as controls. The cyclooxygenase-2 immunoreactivities of paired liver biopsies from 12 patients receiving anti-viral therapy were compared.
Immunohistochemistry and in situ hybridization revealed that cyclooxygenase-2 expression was confined to hepatocytes. Patients with chronic hepatitis B had significantly higher cyclooxygenase-2 expression compared with controls. The cyclooxygenase-2 expression of hepatitis B e antigen-positive and -negative chronic hepatitis B patients was not significantly different, although the necro-inflammatory activity of the latter group was significantly lower. Over-expression of cyclooxygenase-2 in patients with chronic hepatitis B was further confirmed by Western blot and reverse transcription polymerase chain reaction. Twelve hepatitis B e antigen-positive chronic hepatitis B patients received anti-viral therapy: lamivudine in seven and interferon in five. Despite hepatitis B e antigen seroconversion, disappearance of hepatitis B virus DNA in serum, normalization of liver enzymes and a significant reduction in necro-inflammatory activity in all 12 patients, no significant change in cyclooxygenase-2 expression was found.
Chronic hepatitis B is associated with elevated cyclooxygenase-2 levels in hepatocytes, and the over-expression of this enzyme does not reflect inflammatory activity. Up-regulation of cyclooxygenase-2 persists after successful anti-viral therapy.