Accumulating evidence showed that TGF-β1 could lead to epigenetic changes such as H3Kme [25] and H3K9/14Ac [10] in RMCs at p21 gene promoter, which participated in p21 gene upregulation associated with MC hypertrophy in the pathogenesis of DN. This evidence concerns the gene TGFB1 and liver dysplastic nodule.