Free and bound plasmin in esophageal tumors and surrounding tissues in men and women.

Abstract

84 Background: Esophageal squamous cell carcinoma (ESCC) is 2 to 8 times more frequent in men than in women. Tumor progression is directly connected with plasmin participation in destruction of the extracellular matrix and the basement membrane surrounding tumor. The purpose of the study was a comparative analysis of plasminogen (PG), free plasmin (P) and plasmin bound in complex with α2-antiplasmin (PAP) in ESCC tissues of men (M) and women (W). Methods: ESCC tumor tissue (T) and its perifocal zone (PZ) were studied by the ELISA (19 men and 8 menopausal women aged 58-72, st II, G2, T2-3N0-1M0-1). The results were compared to the histologically unchanged tissue from the resection line (RL). PG, P and PAP were measured in 10% homogenates prepared in sterile saline, with recalculation per 1 g wet tissue). Data were processed using Statistica 10. Results: PG content in RL was 1.5 times higher in M than in W. PG in T of M was decreased by 2 times, in W by 3.3 times, in PZ of M – by 2.9 times, in W – by 2.3 times. PG in T and PZ of M was 2.5 and 1.2 times higher than in W. P content in RL of all patients was significantly lower than in other samples, but 1.4 times higher in M than in W. P in T and PZ of M was 3 and 2.5 times higher than in RL, in T and PZ of W – 3.5 and 2.8 times higher than in RL. Significant differences were observed between P levels in T (but not in PZ): 1.3 times higher in M than in W. PAP content was relatively constant in all tissues, with a slight prevalence in T and PZ of W. P/PAP ratio was elevated in all tissues compared to RL, but in T and PZ of M it was 1.4 and 1.2 times higher than in W. P/PAP in RL of M was 1.4 times higher than in W. Conclusions: The results show a higher aggressiveness of P in PZ and T of M, while P formation in T of W was less active. We reported on a higher content of PG activators in T and PZ of M, and taking into account the morbidity statistics and literature data we suppose the effect of androgens on the conditions of PG activation into P and manifestation of its biological features. P in PZ of both M and W can contribute in the expansion of a “tumor field”. P binding in PAP complex was similar in all studied tissues.