BACKGROUND: As an induced enzyme, COX-2 expression is elevated under stimuli from inflammatory mediator or growth factor product. Ki-67, a cell cycle-related proliferative antigen, reflects the tissue proliferative activity. This study analyzed the expressional profile of cyclooxygenase-2 (COX-2) and Ki-67 in hepatolithiasis and bile duct carcinoma tissues, in an attempt to provide evidence for diagnosis and prognosis prediction of disease.

MATERIAL AND METHODS: A cohort of tissue samples from hepatolithiasis with bile duct carcinoma (N=47) patients were analyzed using immunohistochemical (IHC) staining method for the expression of COX-2 and Ki-67, in parallel with hepatolithiasis (N=44) and normal bile duct tissues (N=30). The relationship between expression pattern of COX-2 and Ki-67 and pathological conditions was also analyzed, in addition to the correlation with positive expression in hepatolithiasis samples.

RESULTS: The positive expression rate of COX-2 and Ki-67 in bile duct carcinoma was 76.6% and 80.9%, respectively, and was significantly higher than those in the hepatolithiasis group, which was also higher than the control group. Expression of both COX-2 and Ki-67 is closely related to TNM staging, lymph node metastasis, and differentiation stage. They were also correlated with the mortality rate of patients.

CONCLUSIONS: Both COX-2 and Ki-67 are abundantly expressed in hepatolithiasis and bile duct carcinoma tissues and may play an important role in the disease occurrence, progression, and metastasis.

Keywords: Bile Duct Neoplasms - pathology, Bile Ducts - pathology, Carcinoma - pathology, Cohort Studies, Cyclooxygenase 2 - metabolism, Gene Expression Profiling, Gene Expression Regulation, Enzymologic, Ki-67 Antigen - metabolism, Lithiasis - pathology, Regression Analysis