Prostaglandin E2 production in ovarian cancer cell lines is regulated by cyclooxygenase-1, not cyclooxygenase-2

Prostaglandins Leukot Essent Fatty Acids. 2005 Aug;73(2):103-11. doi: 10.1016/j.plefa.2005.04.014.


The significance of cyclooxygenase-2 (COX-2) expression in ovarian cancer has been discussed. In this study, we found increased expression of COX-1 mRNA and protein in three out of 10 ovarian cancer cell lines. Prostaglandin E 2 (PGE2) production was elevated in these three cell lines, but not in other seven cell lines. COX-2 protein was not detected in any of the cell lines. Cytosolic prostaglandin E synthase (cPGES) mRNA and protein were detected in all 10 cell lines. Membrane-associated PGES-1 (mPGES-1) was detected in some of the ovarian cell lines, but its presence did not correspond with PGE2 production. In contrast, mPGES-2 mRNA and protein were detected in all 10 cell lines. A nonselective COX inhibitor (indometacin) and a selective COX-1 inhibitor (SC-560) strongly inhibited PGE2 production by the three cell lines, while selective COX-2 inhibitors (NS-398 and rofecoxib) did not inhibit PGE2 production. In addition, increased expression of COX-1, not COX-2 protein was observed in the mass of ovarian cancer tissues from 22 patients when compared with that in normal tissue. These findings suggest that COX-1 might be a major enzyme regulating PGE2 production in ovarian cancer cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Inflammatory Agents, Non-Steroidal / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Dinoprostone / biosynthesis*
  • Dinoprostone / genetics
  • Female
  • Humans
  • Ovarian Neoplasms / enzymology*
  • RNA, Messenger / analysis
  • RNA, Messenger / metabolism


  • Anti-Inflammatory Agents, Non-Steroidal
  • RNA, Messenger
  • Dinoprostone