Smad3 has been shown or suggested to have tumor suppressor functions in pediatric T-cell acute lymphoblastic leukemia, gastric cancer, colon cancer, pancreatic cancer, and hepatocellular carcinoma [9–13], and Smad3 point mutations have been identified in colon and pancreatic cancers [14–16 and references therein]. Here, SMAD3 is linked to gastric cancer.