Ligands for these receptor proteins, such as collagens, fibronectins, and laminins, and cellular receptors, such as vascular cell adhesion molecule-1 (VCAM-1) and the intercellular cell adhesion molecule (ICAM) family bind integrins and mediate a variety of cell-matrix and cell–cell adhesion functions, affecting endothelial cells, leukocytes, and leukemia or other tumor cells behavior. This evidence concerns the gene FN1 and leukemia.