Cyclooxygenase (COX)-1, Cyclooxygenase (COX)-2 and E-cadherin Expression in Colorectal Cancer Patients with Hepatic Metastasis

ABSTRACT

PURPOSE: Recent studies have shown that cyclooxygenase (COX)-2 may be involved in colorectal carcinogenesis. In this study, we evaluate the differences of COX-2 expression in patients with synchronous and metachronous hepatic metastasis of colorectal cancer. In addition, the expression of COX-1 and E-cadherin were also evaluated. METHODS: Paraffin embedded blocks were obtained from 41 patients who underwent surgery for colorectal cancer with hepatic metastasis. Samples from primary colorectal cancer, synchronous and metachronous hepatic lesions were stained by immunohistochemistry for monoclonal antibody against COX-1, COX-2, and E-cadherin. RESULTS: In colonic COX-1 expression, there was no significant difference in the degree of COX-1 expression between primary colorectal cancer with synchronous hepatic metastasis and that of metachronous hepatic metastasis (P=0.507). In colonic COX-2 and E-cadherin expression, the degree of COX-2 expression was not different between the two groups. But, the patient survival rate in the positive group of COX-1 and COX-2 expression was lower than in the negative group, respectively (P=0.023, P=0.006). CONCLUSION: The degree of colonic COX-1 and COX-2 expression has an impact on prognosis in synchronous and metachronous hepatic metastasis. Further large-scale study is necessary to determine the meaning of COX-2 expression in colorectal cancer.