Therefore, to better describe the integrin involvement in CF on the basis of different rigidity of growth substrates, Western blot analyses for integrin ανβ5 (Fig. 5a, b) and collagen I (Fig. 5a, c) were performed on total protein extracts of CF seeded on two different substrates and then treated with TGF-β1 and/or cilengitide. This evidence concerns the gene TGFB1 and cystic fibrosis.