The urokinase plasminogen activator and its inhibitors PAI-1 and PAI-2 in primary cutaneous melanoma.

Abstract

Background. We investigated the differences in urokinase plasminogen activator (uPA) and its inhibitors type1 and 2 (PAI-1/2) concentrations in clinically suspected nevi, primary cutaneous melanoma and normal skin and correlations with histopathological prognostic factors of primary melanoma.

Patients and methods. Fifty-one patients were enrolled. The tissue concentrations of uPA, PAI-1 and PAI- 2 were quantified by enzyme-linked immunosorbent assay (ELISA).

Results. Mean uPA and PAI-1 concentrations in melanomas were higher than in normal surrounding skin (uPA: 1.08; vs. 0.48 ng/mgp; PAI-1: 14.07 vs. 2.07 ng/mgp; p < 0.001). uPA and PAI-1 concentrations were higher in melanomas than in nevi, and higher in nevi than in normal surrounding skin (uPA: p > 0.05; PAI-1: p = 0.02). PAI-2 concentration was higher in normal surrounding skin than in nevi and melanomas (p > 0.05). Melanoma uPA, PAI-1 and PAI-2 concentrations correlated significantly with normal skin (r = 0.73, 0.54, 0.38 respectively). PAI-1 was significantly lower in melanomas of Breslow thickness £ 0.75 mm, Clark invasion of 0+I, without microscopic ulceration, without vascular invasion (p < 0.01) than in melanomas of Breslow thickness > 0.75 mm, Clark invasion > II, with ulceration and vascular invasion.

Conclusions. Determination of uPA and PAI-1 can provide significant additional prognostic information for melanoma patients.