SMAD3 and cancer: Although we did not compare disease in Smad3/Rag-DKO mice to Rag2−/− control mice in the studies reported here, we and others have investigated inflammation-associated cancer development in Helicobacter-infected Rag2−/− mice indicating that tumor development in these control mice are minimal in the time frames over which our studies were completed [17], [46], [47], [48].