They show that differentiated adipocytes and the peritumoral adipose tissue from RCC patients with obesity have higher expression of ADAM12 and CYP1B1 genes and proteins compared to overweight and lean patients and suggest that the differential expression of these genes can be related to the ability of AT to worsen tumor invasiveness. The gene discussed is CYP1B1; the disease is obesity due to melanocortin 4 receptor deficiency.