Cyclooxygenase-2 overexpression inhibits cathepsin D-mediated cleavage of plasminogen to the potent antiangiogenic factor angiostatin.

Overexpression of cyclooxygenase (COX)-2 and enhanced synthesis of prostaglandin E2 (PGE2) have been implicated in human endometrial pathologies. To investigate the molecular role of COX-2, the Ishikawa human endometrial epithelial cell line was stably transfected with the pIRES2 vector containing COX-2 cDNA in either the sense or antisense directions. PGE2 concentrations were significantly elevated in the cells transfected with the COX-2 sense compared with wild-type cells or cells transfected with the antisense cDNA (P < 0.