[Molecular mechanism in cell migration].

Lena Claesson-Welsh was awarded the Anders Jahre Prize for young scientists in 1996 in recognition of her research into growth factors and their regulation, knowledge of which is important for an understanding of cancer and angiogenesis. The ability of cells to move along a chemical concentration gradient (chemotaxis) is an important property in many physiological and pathological processes, such as embryogenesis, wound healing and angiogenesis. In angiogenesis, whereby new microcapillaries are formed as sprouts from existing vessels, vascular endothelial cells undergo a complex three-step process. The first step consists in focal degeneration mediated by proteases produced by growth factor-stimulated endothelial cells. The next step is concomitant proliferation and migration of cells into the surrounding tissue. Finally, the cells differentiate to form a continuous lumen. Tumour growth is strictly dependent on angiogenesis. Many tumours produce the growth factor. VEGF, which exerts its effect on receptor tyrosine kineases which are expressed on endothelial cells, thus stimulating endothelial cell chemotaxis toward the tumour. The regulation of endothelial cell migration in this pathological process would be of great therapeutic value.