Here we examine the therapeutic potential of Nox2 inhibition on superoxide generation in saphenous vein ECs (SVECs) from patients with advanced atherosclerosis and type 2 diabetes and on vascular function, vascular damage, and lipid deposition in apolipoprotein E-deficient (ApoE−/−) mice with EC-specific insulin resistance (ESMIRO). The gene discussed is CYBB; the disease is type 2 diabetes mellitus.