UROKINASE-TYPE PLASMINOGEN-ACTIVATOR (UPA) AND PLASMINOGEN-ACTIVATOR INHIBITOR TYPE-1 (PAI-1) IN TISSUE AND SERUM OF HEAD AND NECK SQUAMOUS-CELL CARCINOMA PATIENTS

The aim of this study was to determine urokinase-type plasminogen acti vator (uPA) and plasminogen activator inhibitor type 1 (PAI-1) concent rations in tumour and adjacent normal tissue samples from 58 patients, and in serum samples from 40 of 58 patients with squamous cell carcin oma of the head and neck obtained at diagnosis and after completion of therapy, uPA and PAI-1 serum concentrations were also measured in 28 healthy volunteers who served as controls. Measurements were made usin g enzyme-linked immunosorbent assay (ELISA) techniques. For both uPA a nd PAI-1, significantly elevated concentrations were measured in tumou r tissue as compared with normal tissue (uPA: 8.89 versus 0.41 ng/mg t otal protein (mgp), P < 0.0001; PAI-1: 23.9 versus 1.47 ng/mgp, P< 0.0 001). A statistically significant difference in uPA concentrations was found between normal laryngeal and nonlaryngeal tissue (0.52 versus 0 .3 ng/mgp, P = 0.008), and in PAI-1 concentrations between T1+2 and T3 +4 Stage of disease (17.32 versus 35.63 ng/mgp, P = 0.04). The uPA con centrations positively correlated with those of PAI-1 measured in both tumour (R-S = 0.62, P< 0.0001) and normal tissue (R-S = 0.30, P = 0.0 2). In serum samples, lower concentrations of PAI-1 were measured in t he control group than in patients with cancer (412.0 versus 680.5 ng/m l serum (mls), P = 0.0006). The time of collection of the serum sample did not influence uPA and PAI-1 concentrations, and no association wa s observed between their concentrations and any clinical and histopath ological prognostic factors tested. Our results indicate that both uPA and PAI-1 may play a specific role in the process of invasion and met astasis, and might also be of prognostic value in squamous cell carcin oma of the head and neck. (C) 1998 Elsevier Science Ltd. All rights re served.