Cancer was thought to originate from alterations in intercellular signaling that resulted in the transformation of cells, their uncontrolled proliferation and metastasis. There is now an increasing body of evidence demonstrating that the surrounding matrix and cell-matrix interactions are also major players in this process. Cells adhere and receive signals from various extracellular matrices via transmembrane receptors, the best known of which are the heterodimeric glycoproteins, integrins.