Although the exact pathogenesis of DN cannot be fully elucidated, studies have suggested that the renin-angiotensin-aldosterone system (RAAS), oxidative stress, and TGF-β are relatively common pathogenic mechanisms in the complex pathogenesis of DN (15, 16), and that a more comprehensive blockade of the RAAS may have more clinical benefits for DN (17, 18). This evidence concerns the gene REN and liver dysplastic nodule.