Assessment and prognostic analysis of EGFR, HER2, and HER3 protein expression in surgically resected gastric adenocarcinomas

Abstract

Aim: To investigate the significance of epidermal growth factor receptor (EGFR), human epidermal growth factor receptor (HER)2, and HER3 expression on survival outcomes in Chinese gastric cancer patients. Conclusion: The HER family members showed a high expression in gastric cancer. EGFR protein expression was associated with overall survival. Materials and methods: Formalin-fixed, paraffn-embedded specimens from 121 patients who underwent gastrectomy at Shanghai Renji Hospital from 2007–2010 were retrospectively examined. Fluorescence in situ hybridization and immunohistochemistry techniques were used to identify gene amplification and protein over expression. Correlations between the expression or amplification of HER family genes and clinicopathological parameters were then determined using statistical analysis. Results: EGFR protein over expression, an increase in HER2 copy number and gene amplifca-tion, and HER3 protein over expression were identified in 3 3.1%, 1 7.4%, and 6 2.0% of samples, respectively. Statistical analysis showed a significant association between EGFR expression and tumor invasion depth or tumor stage. HER2 was also shown to be significantly associated with the tumor grade. In addition, EGFR protein over expression was found to be significantly associated with worse overall survival (P=0.03).