ULEX-EUROPAEUS-I LECTIN INDUCES ACTIVATION OF MATRIX-METALLOPROTEINASE-2 IN ENDOTHELIAL-CELLS

In this report, we show that the lectin Ulex europaeus agglutinin I (U EA I), which binds to alpha-linked fucose residues on the surface of e ndothelial cells, mediates activation of the 72-kDa matrix metalloprot einase-2 (MMP-2). A dose-dependent increase in the active 62-kDa form of MMP-2 was observed in conditioned medium from monkey aortic endothe lial cells (MAEC) following incubation with concentrations of UEA I ra nging from 2 to 100 mu g/ml. The increase in the 62-kDa MMP-2 gelatino lytic activity was not reflected by a rise in MMP-2 gene expression. T he UEA I-mediated activation of MMP-2 was blocked by L-fucose, which c ompetes with UEA I for binding to alpha-fucose. These findings may sug gest that a similar in vivo mechanism exists, whereby adhesive interac tions between tumor cell lectins and endothelial cells can mediate MMP -2 activation. (C) 1995 Academic Press, Inc.