The auricular VX2 carcinoma is a suitable animal model for identifying biomarkers for HNSCC therapy response

Abstract

Background/Aim: The rabbit auricular VX2 carcinoma is an established animal model for human head and neck squamous cell carcinoma (HNSCC). Previously, we observed that intraperitoneal oxidative (O3/O2) stress induced tumor remission. Our aim was to evaluate candidate genes associated with tumor regression. Materials and Methods: For identification of tumor remission-related genes, microarray analysis was performed with subsequent validation by polymerase chain reaction (PCR), in situ hybridization, immunohistochemistry and western blot analysis. Results: Microarray analysis indicated a prominent reduction of epidermal growth factor receptor (Egfr, Erbb1) expression levels in regressing tumors. Quantitative PCR confirmed a significant (p<0.005) down-regulation of Erbb1-3 mRNA in regressing VX2 tumors. Histological localization of Erbb1-3 mRNA transcript and protein indicated reduced Erbb gene expression occurring at the level of individual VX2 tumor cells rather than solely being an effect of tumor shrinkage. This study highlights changes in the Erbb gene signature of regressing VX2 carcinomas as a predictor for therapy response. The VX2 carcinoma animal model, therefore, appears suitable for the identification and evaluation of new diagnostic, prognostic and therapeutic biomarkers prior to their application in patients with HNSCC.