CDKN2A and endothelial dysfunction: Since senescence has been identified as an early event promoting endothelial dysfunction [17], the expression level of the senescence markers p53, p21 and p16 was evaluated by Western blot analysis in the outer aortic arch curvature, an arterial site exposed to a high level of shear stress and at low risk, and the inner aortic arch curvature, an arterial site exposed to a low level of shear stress and at high risk [32].