FASN and obesity due to melanocortin 4 receptor deficiency: Inhibitors of enzymes of lipid metabolism (FASN, ACC, CPT1) have been intensively studied and several compounds have shown efficacy in experimental settings: (i) With respect to FASN inhibitors, orlistat, a clinically used anti-obesity drug (a pancreatic lipase blocker), shows anticancer effectivity in multiple cancer models (170).