Zhu et al. found that nicotine-stimulated macrophage exosomal miR-21-3p increases the migration and proliferation of vascular smooth muscle cells by targeting phosphatase and tension homology deleted on chromosome ten (PTEN), thus accelerating the development of atherosclerosis, revealing the partial role of nicotine in atherosclerosis 121. This evidence concerns the gene PTEN and atherosclerosis.