Higher concentrations of N-Shh (human recombinant form of Shh) enhanced cell motility and invasiveness in gastric cancer cells; moreover, treatment of cells with N-Shh led to enhanced TGF-β1 secretion, TGF-β-mediated transcriptional response, expression of ALK5 protein and phosphorylation of SMAD3. The gene discussed is SMAD3; the disease is gastric cancer.