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


OBJECTIVE
We analyzed the expression of COX-2 and HuR in 64 mucinous ovarian carcinoma specimens by immunohistochemistry.


RESULTS
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.


CONCLUSIONS
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.
Erkinheimo
Tiina-Liisa
TL
Department of Obstetrics and Gynecology, University of Helsinki, Helsinki, Finland. tiina-liisa.erkinheimo@helsinki.fi
Sivula
Anna
A
Lassus
Heini
H
Heinonen
Mira
M
Furneaux
Henry
H
Haglund
Caj
C
Butzow
Ralf
R
Ristimäki
Ari
A
D002288:Adenocarcinoma, Mucinous / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000954:Antigens, Surface / Q000096:biosynthesis*; D051546:Cyclooxygenase 2; D003593:Cytoplasm / Q000201:enzymology / Q000378:metabolism; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; D004847:Epithelial Cells / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis*; D016601:RNA-Binding Proteins / Q000096:biosynthesis*; D017154:Stromal Cells / Q000201:enzymology / Q000378:metabolism / Q000473:pathology
D000954:Antigens, Surface; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; C098770:ELAVL1 protein, human; D008565:Membrane Proteins; D016601:RNA-Binding Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases