The role of her2 gene in pathogenesis of gastric cancer and its prognostic effects

BACKGROUND: Gastric cancer is the one of common gastrointestinal cancer tumors. Incidance of gastric tumors changes due to ethnic groups, geographic distribution, diets, economic status, prevalance of h.pylori infections and lifestyle. Genetic factors have an important role in the pathogenesis of gastric cancer and Her2/neu (c-erb B2) gene is one of these genetic factors. AIM: In this study, we aimed to compare level of Her2/neu gene expression of normal and tumoral gastric biopsy tissues by using Real-Time PCR and level of Her2 protein overexpression of the same tissue by using IHC. If there is a positivity we aimed to detect the association between all known prognostic factors such as; age, sex, stage of disease, localization of tumor and histological type of the gastric carcinoma patients. Also, we want to evaluate if this gene expression is a prognostic factor, it can be used as a therapeutical target. METHODS: We evaluated prospectively, 50 newly diagnosed gastric cancer patients into this study. Her2 gene expression of normal and tumoral tissues in mRNA level was obtained by using Real-Time PCR technic and immunohistochemical evaluation was made for Her2 protein overexpression from parafinized tumoral tissues. We compared them with each other. RESULTS: In IHC evaluation result; we detected 5 patients (10 %) had Her2 protein overexpression. In Real-Time PCR reaction datas, we detected that 5 patients (10 % ) had Her2 gene amplification. There was no correlation (0 %) between two methods and there is no relationship statistically (p> 0.05).There is no statistically relationship between prognostic factors and gene expressions (p> 0.05). CONCLUSIONS: Her2 gene amplification and protein overexpression may be related to potential oncogenetic factors.We need extra studies to detect the false negative rate, to evaluate the survey of the patients, and to supply our hypothesis.