SMAD3 and gastric carcinoma: Decreased TGF-β responsiveness was observed when Smad3 expression was lost in gastric carcinoma cells, however, TGF-β-mediated tumor suppressor activity was restored when ectopic expression of Smad3 was reintroduced in gastric carcinoma cells, suggests the Smad3 not only acts as tumor suppressor but might also be the target for epigenetic inactivation in gastric carcinoma (Li et al., 2015).