Expression of c-Met and hepatocyte growth factor in various gastric pathologies and its association with Helicobacter pylori infection.

Activation of the hepatocyte growth factor (HGF)/c-Met signaling pathway was identified to be associated with malignant tumors. The present study aimed at determining the expression of HGF and c-Met in gastric carcinogenesis and its association with Helicobacter pylori infection. Gastric biopsies were obtained from 160 H. pylori-negative and -positive patients, including those with chronic gastritis, intestinal metaplasia, dysplasia and gastric cancer (GC). Proteins were extracted from GES-1, gastric epithelial, and AGS, gastric adenocarcinoma, cells following co-culture with H. pylori in vitro. The expression of HGF and c-Met in gastric tissues or cells was determined using immunohistochemistry and western blot analysis. The expression of c-Met increased in GC tissues (72.5%) compared with that in pre-cancerous lesions (17.5, 17.5 and 30%). Additional analysis identified that the expression of HGF and c-Met was significantly increased in the presence of H. pylori infection in dysplasia and gastric cancer samples. Furthermore, H. pylori may activate the HGF/c-Met signaling pathway in vitro, which may contribute to gastric carcinogenesis.