In the present study, we assessed the suppressive effects of Ucn1 on the inflammatory response and proliferation of human ECs, human macrophage foam cell formation, the migration, proliferation, and ECM production in human VSMCs in vitro, and the development of atherosclerotic lesions in apolipoprotein E-deficient (Apoe−/−) mice, an animal model of atherosclerosis, in vivo. The gene discussed is UCN; the disease is atherosclerosis.