We observed that TGF-β1 stimulated upregulation of α-SMA and accompanied by downregulation of E-Cad (Figure 4a,4g,4h), indicating that TGF-β1 initiated renal fibrosis via epithelial mesenchymal transition (EMT) in HK-2 cells, which was in accordance with previous reports 40, 41. The gene discussed is ACTA1; the disease is renal fibrosis.