[VLA and alpha6, beta4 integrins. Expression in normal and neoplastic human tissues]

Among the cellular adhesion molecules, the integrin family, more particularly the VLA (Very late antigen) integrins, is currently the subject of numerous investigations in pathology. These integrins are involved in cell-cell contact or cell-matrix adhesions. During neoplastic diseases, cellular expression of integrins changes and a study of the modifications could allow a new etiopathogenic approach carcinogenesis and metastatic phenomena. New prognostic factors may be defined in tumor pathology. We describe the general structure of integrins and the mechanisms of their binding with matricial ligands and with cytoskeleton. The expression of VLA integrins and the alpha6beta4 heterodimer on normal and neoplastic human tissues is then described. Finally, we describe the involvement of these proteins in tumor progression and tissue invasion.