Human epidermal growth factor receptor-2 assessment in cancerous and precancerous lesions of the stomach in presence of Helicobacter pylori

Aims: Importance of human epidermal growth factor receptor-2 (HER-2) testing in cancer is increasing, and in the other hand, there is a hypothesis about roles of Helicobacter pylori (H. pylori) in gastric cancer (GC) development. We seek to investigate the HER-2 expression in the presence of H. pylori infection in patients with gastric GC and precancerous lesions. Subjects and Methods: From 224 archived blocks, 58 samples with chronic gastritis, 58 intestinal metaplasia (IM), 58 gastric dysplasias, and 50 gastric adenocarcinoma cases were selected as our principal groups. Each group was subdivided into H. pylori-positive and H. pylori-negative subgroups. Immunohistochemical method was performed for detection of HER-2 expression in gastric biopsies using a polyclonal antibody. The staining intensity was quantified and differences among groups were compared using Mann–Whitney U and Kruskal–Wallis tests. P < 0.05 was set as statistically significant. Results: Results showed that HER-2 expression among the four principal groups was statistically significant (P < 0.05). There was a significant increase of immunohistochemical expression of HER-2 in H. pylori-positive chronic gastritis in comparison with H. pylori-negative subgroup (P < 0.05). Difference of HER-2 expression between H. pylori-positive and H. pylori-negative subgroups in dysplasia, IM, and GC groups was not statistically significant (P > 0.05). Conclusion: The present study proposed that HER-2 overexpression in gastric tissues probably had important roles in the progression of cancer and above-mentioned process was probably associated with H. pylori infection in the early stages of precancerous lesions.