UPMODULATION OF ALPHA-V-BETA-1INTEGRIN EXPRESSION ON HUMAN TUMOR-CELLS BY HUMAN INTERLEUKIN FOR DA-CELLS LEUKEMIA INHIBITORY FACTOR AND ONCOSTATIN-M - CORRELATION WITH INCREASED CELL-ADHESION ON FIBRONECTIN

Integrins belong to a large family of heterodimeric membrane glycoprot eins which mediate cell-cell or cell-extracellular matrix interactions . These interactions could play a major role during the migration of t umor cells across the extracellular matrix and vascular endothelium an d would thus appear to be requisite for the metastatic process. Pretre atment of the Foss human melanoma cell line with HILDA/LIF or OSM, two cytokines involved in acute-phase response, increased the expression of membrane alpha nu beta 1 1.5-2-fold. The same phenomenon was observ ed on the SK-N-SH human neuroblastoma cell line. alpha nu beta 1 upmod ulation was concomitant with improved tumor cells attachment to the fi bronectin matrix. This greater adhesion oi tumor cells to fibronectin was inhibited by specific monoclonal antibodies against alpha nu or be ta 1 integrin subunits. Similar results were obtained after TNF-alpha treatment. Our findings demonstrate the ability of HILDA/LIF and OSM t o modulate tumor cell capacity to adhere to the matrix component, sugg esting a potential role for these cytokines in modulation of tumoral p rogression. (C) 1995 Wiley-Liss, Inc.