Experimental data show that although expression of both VCAM-1 and ICAM-1 is upregulated in atherosclerotic lesions, VCAM-1, but not ICAM-1, plays a dominant role in the initiation process of atherosclerosis, since VCAM-1 is found in inflammatory regions predisposed to atherosclerotic lesions, while low levels of ICAM-1 are found in normal arterial segments expressed by normal endothelial cells [44]. This evidence concerns the gene ICAM1 and atherosclerosis.