EVIDENCE OF INVOLVEMENT OF CD44 IN ENDOTHELIAL-CELL PROLIFERATION, MIGRATION AND ANGIOGENESIS IN-VITRO

Angiogenesis is essential for tumor growth and metastasis. In the proc ess of angiogenesis, the interaction between adhesive proteins of endo thelial cells and extracellular matrix components plays an important r ole by mediating cell attachment, which is indispensable for their mot ility, and by transmitting the regulatory signals for cell locomotion and proliferation. In this study, we examined the hypothesis that CD44 expressed on the endothelial cell surface is involved in the angiogen esis process. The experiments using calf pulmonary artery endothelial cells (CPAE) and a human microvascular endothelial cell line (HMEC-1) show that a monoclonal antibody against CD44 (clone J 173) inhibits en dothelial cell proliferation by about 30% and migration by 25-50%, and abolishes the stimulating effect of hyaluronan polysaccharides on end othelial cell migration and proliferation, This antibody also suppress es the capillary formation of CPAE in an in vitro model of angiogenesi s using fibrin matrix. These results provide evidence of the involveme nt of endothelial-cell-associated CD44 in angiogenesis. (C) 1996 Wiley -Liss, Inc.