IFNB1 and coronary stenosis: Recently, genome-wide expression analysis in patients with coronary artery stenosis and insufficient coronary collateral artery development was performed, and it was reported that interferon (IFN)-β signaling is enhanced in the patients.1 Thereafter, the efficacy of IFN-β on the vascular diseases was shown in a mouse model.2 However, the mechanisms related to the efficiency are not elucidated sufficiently, although antiproliferative effect against advanced smooth muscle cell (SMC) growth was shown.