The Relation Between the Expression of Cyclooxygenase-2 and Biologic Behavior of Human Pancreatic Cancer

Objectives To investigate the expression of cyclooxygenase-2(COX-2) in different pancreatic tissues in order to explore its role and significance in development of pancreatic cancer. Methods Immunohistochelistry staining (Picture TM two steps method) was used to detect expression of COX-2 in 47 cases of paraffin-embedded pancreatic carcinomas tissue, 12 of pancreatic intraductal neoplasias(PIN) and 10 of normal pancreatic tissues. Results The positive expression of COX-2 was noted in 2 out of 10 cases of normal pancreatic tissues; the high expressions of COX-2 were found in PIN and pancreatic carcinomas(75%,68% respectively), which were significantly higher than that in normal pancreatic tissues respectively (P0.05). The rastes of COX-2 expression in well-differentiated, moderately-differentiated and poorly-differentiated pancreatic carcinoma tissues were 40%,69% and 81%. The significant difference was observed between well-differentiated and poorly-differentiated pancreatic carcinomas tissues (P0.05). The expression of COX-2 was as high as 84% in pancreatic carcinomas with lymph node metastasis, which was significantly higher than those without lymph node metastasis (P0.05). Otherwise, no significant correlation was noted between COX-2 expression and the location, size, adjacent tissues invasion, and distant metastasis of pancreatic carcinomas(P0.05). The positive expression of COX-2 was 38% among those patients suffering from pancreatic carcinoma with 1-year post-operation survival, which was lower than those with less than 1-year post-operation survival(P0.05). Conclusion COX-2 expression in PIN and pancreatic carcinomas may be involved in the carcinogenesis of pancreatic cancer. COX-2 may be an useful index to predict the differentiated level, lymphoid metastasis and prognosis of pancreatic cancer.