ELEVATED PLASMA-LEVELS OF UROKINASE PLASMINOGEN-ACTIVATOR RECEPTOR INNONSMALL CELL LUNG-CANCER PATIENTS

The urokinase plasminogen activator (uPA) is involved in extracellular matrix degradation during cancer invasion. Binding of uPA to a specif ic cell surface receptor (uPAR) is a key step in this process. We have previously reported that high levels of uPAR in squamous cell lung ca ncer tissue extracts are associated with poor prognosis (Pedersen et a l., Cancer Res 1994, 54, 4671-4675). Recently we found that uPAR is pr esent in blood plasma from healthy donors as determined by enzyme-link ed immunosorbent assay (ELISA) and chemical cross-linking. We now repo rt that uPAR in plasma from 17 patients with non-small cell lung cance r (NSCLC) was significantly higher than in 30 healthy controls (P = 0. 0004), while no significant increase was found in plasma from 14 patie nts with small cell lung cancer (SCLC). The increased levels of uPAR i n the plasma from NSCLC patients is likely to be due to release of uPA R from the tumour tissue, and may, therefore, be related to prognosis. (C) 1997 Elsevier Science Ltd.