TNF and obesity due to melanocortin 4 receptor deficiency: Exposure of differentiated human podocytes to factors associated with obesity, insulin resistance and type 2 diabetes did not increase the expression of FOXC2 as observed by quantitative RT-PCR for tumor necrosis factor-α (TNF-α) and transforming growth factor β (TGF-β) (Fig. 2A and B), and by quantitative Western blotting for angiotensin II and a combination of glucose and palmitate (Fig. 2C-F).