Expression of RAGE in Helicobacter pylori infested gastric biopsies

Inflammation is a common phenomenon present in gastric mucosa of patients infected with H. pylori. Activation of the RAGE/multiligand axis is thought to be a relevant factor in cancer-mediated inflammation. RAGE is a membrane receptor, belonging to the immunoglobulin family, and the over-expression of RAGE has been associated with increased invasiveness and metastasis generation in different types of cancer, including gastric cancer. Furthermore recent experiences show that the use of its soluble form (sRAGE) or silencing of the gene coding for this receptor could provide therapeutic benefits in cancer. To evaluate the immunohistochemical expression of RAGE, MUC-1, β-Catenin free and phosphorylated, Cyclin-D1 and GSK3 in gastric biopsy specimens infected with H. pylori. Immunohistochemical analysis was carried out in gastric biopsies from 138 patients: 55 with inflammatory injury (no atrophic gastritis), 42 with pre-cancerous conditions (atrophy or intestinal metaplasia) and 41 with dysplastic lesions or in situ adenocarcinoma. There was a high rate of positive RAGE expression in the three groups of biopsies. Biopsies with dysplasia or in situ carcinoma had a significantly higher percentage of RAGE expression than the other groups of biopsies. The increased RAGE expression reported in both dysplasia and incipient cancer support the role of the multiligand/RAGE axis in gastric carcinogenesis.