Cyclooxigenase-2 and osteopontin in gastric pre-neoplastic lesions in relation to H-pylori infection and grade of inflammation

Abstract

The association between Helicobacter-pylori-induced inflammation and gastric adenocarcinoma is well documented and it has been suggested that the pro-mitotic and apoptotic effect of Cyclooxygenase-2 and Osteopontin on the epithelial cells of the gastric mucosa may have a role in carcinogenesis of the gastric mucosa.The aim of this study was to determine the expression of Cyclooxygenase-2 and Osteopontin in normal gastric mucosa, mucosa with gastritis and gastric mucosa with intestinal metaplasia, in relation to Helicobacter-pylori infection and grade of inflammation. Immunohistochemistry was performed on 108 gastric biopsies in order to detect Cyclooxygenase-2 and Osteopontin expression. The intensity and percentage of staining were evaluated using the H-Score, and its association with grade of inflammation, Helicobacter pylori infection and intestinal metaplasia was determined. Expression of Cyclooxygenase-2 and Osteopontin was higher in gastric biopsies (values shown respectively) with Helicobacter-pylori infection (179.9/142.3), intestinal metaplasia (208.8/179.3) or higher grades of inflammation (190/135.7) in comparison to normal gastric mucosa (100.7/80) or mild grade of inflammation (128.4/128.4), (p<0.05).There is an overexpression of Cyclooxygenase-2 and Osteopontin in gastric mucosa with H. pylori infection, intestinal metaplasia and high grades of inflammation, suggesting a constant up-regulation of protein expression in response to the inflammatory process generated by a Helicobacter-pylori infection, leading to the development of intestinal metaplasia.