Expression of somatostatin receptor subtype 3 in the gastric mucosa of dyspeptic patients in relation to Helicobacter pylori infection and a family history of gastric cancer.

BACKGROUND AND AIM

The cytotoxic activity of Helicobacter pylori contributes significantly to the pathogenesis of gastric carcinoma. A preliminary study suggested that somatostatin receptor subtype 3 (SSTR3) might play a role in cell apoptosis and the growth of gastric cancer. The aim of the present study was to determine the influence of H. pylori infection and a family history of gastric cancer on the expression of SSTR3 in the gastric mucosa of non-cancer patients with dyspepsia.

METHODS

The expression of the SSTR3 gene in the gastric mucosa of the stomach antrum and corpus of 53 patients was determined by the use of quantitative reverse transcription-polymerase chain reaction.

RESULTS

The SSTR3 mRNA level was lower in the H. pylori-infected patients, as compared to the non-infected patients, independently of a family history of gastric cancer and stomach topography. The greatest decrease of approximately 40% and 35% (P < 0.05) was observed for the antrum of the H. pylori-positive patients without and with a family history of gastric cancer, respectively. In the corpus, these differences were much smaller, regardless of a family history of gastric cancer. Interestingly, for H. pylori-negative patients, the density (at the mRNA level) of the SSTR3 receptor in the antrum was higher than in the corpus mucosa.

CONCLUSIONS

A decrease in the density of SSTR3 (especially in the antrum) in individuals with H. pylori infection and particularly with a family history of gastric cancer may point to an environmental and inherited predisposition in the development of distal gastric cancer.