The comparison of her2 gen amplification and CERBB-2 protein expression in undifferentiated nasopharyngeal carcinoma and the condition of apoptosis in ebv positive nasopharyngeal carcinoma and in ebv positive chronic nasopharyngitis

Nasopharyngeal carcinoma (NPC) is a significantly rare tumor. Undifferentiated nasopharyngeal carcinoma (UNPC) is the more frequently seen histological subtype which also shows a prominent susceptibility to radiotherapy. The therapeutic effect of radiation is related to apoptosis and cell cycle. Recent studies are concentrated on the apoptotic markers and protooncogenes which indicate the treatment response. 17 UNPC and 10 chronic nasopharyngitis patients (a total of 27 patients) have been included in this study. Immunohistochemical staining and chromogenic in situ hybridization (CISH) techniques were applied to 17 UNPC cases, in order to evaluate cerbB-2 protein expression and HER2 gene amplification. In 27 patients, with immunohistochemical staining, EBV and p53 positivity, Bcl-2 and c-myc expression and Ki-67 proliferation index and with terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) technique apoptosis were evaluated. All of 10 chronic nasopharyngitis patients and 6 (%35.3) out of 17 UNPC patients were EBV positive. There was a significant difference between two groups regarding EBV positivity (p=0.001). A significant relation between EBV and gender was detected in UNPC group (p=0.029). Statistically significant differences between two groups regarding Bcl-2 and c-myc expression, p53 positivity and Ki-67 proliferation index were determined (p<0.001, p=0.003, p<0.001, p<0.001 respectively). No healthy results could be obtained from the TUNEL technique, therefore the results were not included in statistical analysis. No staining with cerbB-2 and no HER2 gene amplification with CISH method was detected in all 17 UNPC cases. In this study p53 positivity, Bcl-2 and c-myc expression and also Ki-67 proliferation index were significantly higher in UNPC cases comparing to chronic nasopharyngitis patient group. In UNPC group, along with p53 positivity high Ki-67 proliferation index were observed. Investigation of presence of HER2 gene amplification and its product cerbB-2 protein with IHC and CISH techniques, showed no cerbB-2 protein expression and HER2 gene amplification in all UNPC cases that were diagnosed in our department.