Structural and biologic properties of integrin-mediated cell adhesion.

The integrins are a family of proteins that mediate cellular adhesion mechanisms involved in development, differentiation, wound healing, immune recognition, and inflammation. In addition, these adhesion receptors also potentiate disease states including cancer, thrombosis, and inflammatory diseases. To understand the role of integrins in these processes, it is important to define their structural and functional properties. It is also imperative to understand the distribution of integrins on normal and malignant cell types. Integrins are regulated on the cell surface, and these events likely promote specific cellular adhesion mechanisms. This is of particular concern among tumor cells, which not only attach to the extracellular matrix but must invade and migrate through it. Integrins are surface-expressed proteins that mediate a linkage to the cytoskeleton within the cell, and thus cell morphology and traction during migration. Thus, by understanding the structural basis of integrin--ligand and integrin--cytoskeleton interactions we will gain insight into the molecular basis of cancer, thrombosis, wound healing, and inflammation.