Normal Mucosae of Human Urinary Bladder Comparative Study of Plasminogen Activators in Cancers and Updated Version

We have developed a highly sensitive sandwich enzyme immunoassay for determination of urokinase-type plasminogen activator (u-PA) and tissue-type plasminogen activator (t-PA) antigen levels in extracts of human tissues. We determined antigen levels of PAs in extracts of 31 primary cancers and 15 normal mucosa! tissues of the urinary bladder using this method. U-PA antigen levels in extracts of bladder cancers were significantly higher than those in normal tissues (p < 0.005). U-PA antigen levels significantly increased as histolÃ3gica!grading of malig nancy advanced. There was no correlation between t-PA antigen level and malignancy. These results indicate that an increase of u-PA antigen level may be a parameter of malignant transformation and may play an important role in invasiveness of cancer.