Cyclooxygenase-1 and 2 in normal and malignant human ovarian epithelium.
OBJECTIVE
Cyclooxygenase-1 and 2 (COX-1 and COX-2) play important roles in normal physiology and are often dysregulated in neoplastic tissues. The present study determines whether COX-1 and COX-2 are expressed in ovarian cancers and whether the pattern of expression of these enzymes reveals clues to their roles in this cancer.


METHODS
The expression of COX-1 and COX-2 proteins in 9 normal human ovaries, in 137 cases of ovarian cancers of epithelial origin (83 primary and 54 metastatic), and in 7 ovarian cancer cell lines was examined by immunohistochemistry and western analysis.


RESULTS
COX-1 protein was present in 95/137 (69.3%) of the total cancers studied, with 55/83 (66.3%) of the primary cancers and 40/54 (74.1%) of the metastatic cancers positive for protein. COX-2 was present in 97/137 (70.8%) of all cancers studied, with 53/83 (63.9%) of the primary cancers and 44/54 (81.5%) of the metastatic cancers positive for protein. Notably, the quickscores for COX-2-positive staining were significantly higher in metastatic cancers. Moreover, COX-2 immunostaining was frequently found at the advancing margin of tumor invasion or in new metastatic loci. COX-1 protein expression was observed in the ovarian surface epithelial cells, especially that of the inclusion cysts. COX-1 was also detected by western blot in seven of nine ovarian cancer cell lines. However, no COX-2 was detected in either normal epithelium or cancer cell lines.


CONCLUSIONS
COX-1 and COX-2 were expressed in every type of ovarian epithelial cancer, suggesting that each may contribute to the cancer development or progression.
Li
Shuanfang
S
Laboratory of Women's Health, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
Miner
Kelly
K
Fannin
Rick
R
Carl Barrett
J
J
Davis
Barbara J
BJ
D000328:Adult; D045744:Cell Line, Tumor; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D004848:Epithelium / Q000201:enzymology; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007527:Isoenzymes / Q000096:biosynthesis* / Q000502:physiology; D008565:Membrane Proteins; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000201:enzymology* / Q000473:pathology; D010053:Ovary / Q000201:enzymology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000502:physiology
D007527:Isoenzymes; D008565:Membrane Proteins; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases