Plasminogen activator activity in human endometrial carcinoma.

Plasminogen activator activity (PAA) has been proposed as an indicator of aggressiveness of tumors and has been shown to be hormonally modulated. To test this hypotheses in human endometrial carcinoma, tumor explants were assayed for PAA secretion and the results correlated with histopathologic criteria of aggressiveness. The effect of medroxyprogesterone acetate (MPA) on PAA secretion was also investigated. Lower levels of PAA were found to be associated with tumors displaying aggressive tendencies. MPA generally decreased PAA secretion. No apparent correlation was found between estrogen or progesterone receptor concentrations and PAA levels.