However, low NOX1 expression has also been reported in atherosclerotic coronary arteries of patients undergoing bypass grafting while NOX2 and NOX4 expression were significantly higher in vessels with coronary artery disease (CAD) vs. non-CAD [27,28] (Table 1); thus, whether NOX1 is involved in human atherogenesis is unclear. Here, NOX4 is linked to coronary artery disorder.