H. pylori infection increases gastric mucosal COX2 and mTOR expression in chronic gastritis: Implications for cancer progression?

• Published in: Pathophysiology (Amsterdam) 2017-09, Vol.24 (3), p.205-211
• Main Authors: Badary, Dalia M., Rahma, Mohammed Zakaria Ali Abu, Ashmawy, Ahmed M., Hafez, Mohamed Z.
• Format: Article
• Language: English
• Subjects: COX2; Gastritis; H. pylori; mTOR
• ISSN: 0928-4680; 1873-149X
• DOI: 10.1016/j.pathophys.2017.05.004

Helicobacter Pylori is a Gram-negative bacterium that infects the human stomach and plays an important role in the pathogenesis of chronic gastritis. H. pylori associated chronic gastritis affects various molecular markers related to gastric cancer development. The aim of this study to assess the effect of H. pylori infection on gastric mucosa and to explore its role in gastric carcinogenesis via COX2 and mTOR mucosal expression. This study comprised archival blocks from 60 dyspeptic patients who underwent gastric endoscopic biopsies for histopathological examination. The blocks were cut at 4 μm thicknesses, stained with hematoxylin and eosin to score, using updated Sydney system, and subjected to Giemsa stain to assess H. pylori infection. Then, immunohistochemical method was carried out to determine the expression of COX2 and mTOR. Increased H. pylori colonization was significantly correlated with increased severity of inflammation, activity, atrophy, intestinal metaplasia, and the presence of high-grade dysplasia. Also, studied molecular markers were significantly associated with increased H. pylori colonization and presence of severe metaplasia, atrophy, and dysplasia. These findings suggest that there is a positive feedback loop between H. pylori infection and the pathogenesis of gastric mucosal changes. Also, mTOR and COX2 over expression cause premalignant changes and subsequent tumor occurrence. This may help in providing innovative approaches for the detection of patients-with a higher chance of cancer development, and in trying to introduce effective therapy preventing tumor occurrence, or even using these molecular markers as potential targets for tumors treatment strategies.