Lack of clinical usefulness of Das-1 monoclonal antibody and mucin expression as risk markers of gastric carcinoma in patients with gastric intestinal metaplasia

Biomarkers predicting development of metachronous gastric cancer after endoscopic resection: an analysis of molecular pathology of Helicobacter pylori eradication

Metachronous gastric cancer (MGC) after endoscopic resection (ER) of gastric cancer still occurs to some degree even after Helicobacter pylori (H. pylori) treatment. We evaluated whether two biomarkers related to carcinogenesis expressed in intestinal metaplasia (IM) become predictors for MGC development after eradication. We performed a hospital-based, case-control study of 75 patients, including 50 mucosal cancer patients who had undergone ER (Group DYS), and 25 age- and sex-matched chronic gastritis patients for whom H. pylori had been successfully eradicated (control). Additionally, Group DYS patients were divided into two groups: 25 successfully H. pylori-eradicated (eradicated group) and 25 un-eradicated patients (persistent group). All patients were followed for 1 year. We analyzed microsatellite instability (MSI) and immunoperoxidase assays using a monoclonal antibody for the colonic phenotype (Das-1). Both MSI and Das-1 reactivity in IM were significantly higher in Group DYS than in the control (p < 0.05 and p < 0.01, respectively). MSI and Das-1 reactivity were strong and independent predictors for gastric cancer (OR = 7.09, 95% CI 1.27-39.6, p = 0.03 for MSI and OR = 4.96, 95% CI 1.64-15.0, p = 0.005 for Das-1 reactivity). The incidence of MSI tended to decrease in the eradicated group (p = 0.07), but not in the persistent group. The Das-1 immunoreactivity in IM also declined in both the eradicated group and the control. Interestingly, all MGCs after ER were positive for MSI or Das-1 reactivity. MSI or Das-1 reactivity in IM strongly predicts the development of MGC. Patients in whom these biomarkers persist after eradication may therefore have a high risk of developing MGC.

Gastric diseases in Mongolian gerbils infected with different strains of Helicobacter pylori

Helicobacter pylori (H.pylori) is a bacterium responsible for one of the most widespread infections found in humans. It colonizes the gastric mucosa and can result in chronic gastritis and gastric cancer. The incidence of spontaneous gastric gastritis is low in Mongolian gerbils, and spontaneous H.pylori infection can not be detected in this animal. Since H.pylori-related gastric diseases in Mongolian gerbils are very similar to those in humans, they have been considered as ideal animals to establish H.pylori infection models. However, different strains of H.pylori may induce different types of pathologic changes in Mongolian gerbils. Clarification of the pathogenic mechanisms of different strains of H.pylori may provide a theoretical basis for screening appropriate H.pylori strains and directing individualized treatment in patients with H.pylori-related gastric diseases. In this paper, we review the recent progress in research of gastric diseases in Mongolian gerbils infected with different strains of H.pylori.