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

• Published in: Gynecologic oncology 2005-10, Vol.99 (1), p.14-19
• Main Authors: Erkinheimo, Tiina-Liisa, Sivula, Anna, Lassus, Heini, Heinonen, Mira, Furneaux, Henry, Haglund, Caj, Butzow, Ralf, Ristimäki, Ari
• Format: Article
• Language: English
• Subjects: Adenocarcinoma, Mucinous - enzymology; Adenocarcinoma, Mucinous - metabolism; Adenocarcinoma, Mucinous - pathology; Adult; Aged; Aged, 80 and over; Antigens, Surface - biosynthesis; COX-2; Cyclooxygenase 2; Cytoplasm - enzymology; Cytoplasm - metabolism; ELAV Proteins; ELAV-Like Protein 1; Epithelial Cells - enzymology; Epithelial Cells - metabolism; Epithelial Cells - pathology; Female; Humans; HuR; Immunohistochemistry; Inhibin-α; Membrane Proteins; Middle Aged; Mucinous; Ovarian cancer; Ovarian Neoplasms - enzymology; Ovarian Neoplasms - metabolism; Ovarian Neoplasms - pathology; Prostaglandin-Endoperoxide Synthases - biosynthesis; RNA-Binding Proteins - biosynthesis; Stromal Cells - enzymology; Stromal Cells - metabolism; Stromal Cells - pathology
• ISSN: 0090-8258; 1095-6859
• DOI: 10.1016/j.ygyno.2005.04.047

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. We analyzed the expression of COX-2 and HuR in 64 mucinous ovarian carcinoma specimens by immunohistochemistry. In mucinous tumors, high COX-2 protein expression was found in epithelial cancer cells in 39% (22/56) and in stromal cells in 24% (13/55) of the specimens. The expression of COX-2 in cancer cells correlated with high grade ( P = 0.0285), but stromal COX-2 expression had no correlation with any clinical parameter tested. Cytoplasmic HuR protein expression was observed in cancer cells in 47% (27/57) and in stromal cells in 7% (4/56) of the mucinous tumors, and it correlated with COX-2 expression in the cancer cells ( P = 0.0162) but not in the stroma. Our results support the hypothesis that cytoplasmic HuR is connected to COX-2 expression in ovarian carcinoma, but that its role is restricted to the transformed epithelial cancer cells.