FASN

Class

small molecule

Notes

original target text: FASN inhibitor

Fatty acid synthase (FASN) is a large, multi-enzyme protein that carries out de novo lipogenesis: the stepwise construction of long-chain fatty acids, principally palmitate, from the small building blocks acetyl-CoA and malonyl-CoA, using energy and reducing equivalents supplied by NADPH. Most normal adult tissues obtain fatty acids mainly from the diet and rely relatively little on this internal synthesis pathway, but many cancer cells switch on FASN strongly to generate the lipids needed for rapidly built cell membranes, signaling molecules, and energy stores, a shift sometimes described as reprogrammed lipid metabolism. The liver and fat tissue also depend on FASN activity, and excess de novo lipogenesis contributes to fat accumulation in conditions such as non-alcoholic fatty liver disease. Small-molecule inhibitors block the enzyme's catalytic activity, aiming to starve lipid-dependent tumor cells of a self-made fuel and building-block source, or to reduce pathological fat synthesis in the liver. Because FASN sits at a metabolic crossroads rather than in a single disease-specific pathway, its inhibition has been explored across oncology and metabolic disease, wherever excessive internal fatty acid production drives pathology.