SMAD4, also called SMAD family member 4, Mothers against decapentaplegic homolog 4, or DPC4 (Deleted in Pancreatic Cancer-4) is a central mediator of TGF-β signalling by forming complexes with receptor-activated SMADs (SMAD-2 and -3). The gene discussed is SMAD4; the disease is pancreatic neoplasm.