Correlation of tissue and blood plasminogen activation system in breast cancer

The plasminogen activation system plays a crucial role during cancer invasi on and metastasis. In the solid tumor, urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor type-1 (PAI-1) and uPA receptor (uP AR) are considered as prognostic factors. In this study, we have investigat ed whether secretion of the uPA, PAI-1 and uPAR from the primary breast can cer tissue can be detected in the blood of the patients using the ELISA ass ay. We have found that the plasminogen activation system (uPA, PAI-1, uPAR) of tumor tissue is activated from the early stage of breast cancer. Howeve r, only a number of metastatic lymph nodes was a prognostic factor in multi variate analysis for relapse. The blood level of the plasminogen activation system correlated with that of tissue in an order of uPAR (r(2) = 0.61; P = 0.001), uPA (r(2) = 0.35; P = 0.001) and PAI-1 (r(2) = 0.11; P = 0.001). We conclude that the total uPAR level of cancer tissue can be substituted b y that which is detected in the blood for further clinical applications. (C ) 2000 Elsevier Science Ireland Ltd. All rights reserved.