TGFB1 and focal segmental glomerulosclerosis: Interestingly, in biopsies diagnosed as MCD, FSGS, MN, and DRD, mRNA of alpha-actinin-4, podocin, and podocalyxin were downregulated and, at the same time, the mRNA of TGF-β1, CTGF, and VEGF-A were upregulated, suggesting that, after acute podocyte injury, the inductors of tissue fibrosis were highly activated.