THE ROLE OF ALPHA-V-INTEGRINS IN TUMOR PROGRESSION AND METASTASIS

Metastatic tumour spread is a pathologic process which can be describe d as altered cell growth associated with a series of adhesion/de-adhes ion events which are coupled with regulated tissue degradation. Adhesi on to, and migration through, the extracellular matrix (ECM) is necess ary for the tumour invasion which is an important part of the metastat ic process. Efficient proteolytic digestion of the molecules of the EC M appears to be facilitated by the localization of proteases at the ce ll surface-tissue interface (see also review by Stetler-Stevenson). In deed, there is evidence from in-vitro studies to suggest that restrict ion of these enzymes to focal contact sites (areas of cell-substratum contact) may occur and that this sub-cellular juxtaposition of recepto rs and enzymes co-ordinates regulation of adhesion and proteolysis by the neoplastic cells. How such coordinated regulation is achieved and how this dynamic interplay is controlled during tumour development and progression are important areas of investigation.