Cytoplasmic HuR expression correlates with epithelial cancer cell but not with stromal cell cyclooxygenase-2 expression in mucinous ovarian carcinoma.

Unlabelled: Cyclooxygenase-2 (COX-2) expression has been found to associate with poor prognosis in several types of carcinomas. HuR is an mRNA stability protein and it regulates the expression of COX-2.

Objectives And Methods: We analyzed the expression of COX-2 and HuR in 64 mucinous ovarian carcinoma specimens by immunohistochemistry.

Elevated cyclooxygenase-2 expression is associated with altered expression of p53 and SMAD4, amplification of HER-2/neu, and poor outcome in serous ovarian carcinoma.

Purpose And Experimental Design: Cyclooxygenase-2 (COX-2) is frequently expressed in human adenocarcinomas and inhibition of COX-2 suppresses tumor formation in various animal models of carcinogenesis. We analyzed expression of COX-2 protein in human serous ovarian carcinomas by immunohistochemistry (n = 442) and by Western blotting (n = 12) and COX-2 mRNA by reverse transcriptase PCR (n = 12). COX-2 immunoreactivity was correlated to clinicopathological variables and to expression of p53 and SMAD4 as detected by immunohistochemistry and to amplification of HER-2/neu as detected by in situ hybridization.

Cytoplasmic HuR expression correlates with poor outcome and with cyclooxygenase 2 expression in serous ovarian carcinoma.

Cyclooxygenase-2 (COX-2) expression has been shown to associate with poor prognosis in ovarian cancer, and an mRNA stability protein HuR has been shown to enhance expression of COX-2 in tissue culture conditions. We found cytoplasmic immunoreactivity for HuR protein in 52% (233 of 445) of serous-type ovarian carcinoma specimens, and it associated with high COX-2 expression (P = 0.0045) and with clinicopathological variables, including poor prognosis (P < 0.