Abstract 3198: Ron tyrosine kinase synergizes with EGFR to confer aggressive phenotype in head and neck cancers

Background: Data generated over the past 20 years strongly support a critical role for EGFR in head and neck squamous cell carcinomas (HNSCC). While there have been successes with EGFR inhibitors in the treatment of this cancer, results have not been dramatic and additional molecular targets are needed. We previously showed that the loss of Ron activity negatively impacted squamous cell tumor growth in a murine model. Based on these results, we hypothesized that high Ron expression confers an aggressive phenotype in HNSCC. To test this hypothesis, we analyzed 73 primary HNSCC for Ron and correlated its expression with clinical and pathological features. We also assessed the biological and biochemical response of altering Ron in HNSCC cells. Methods: Snap frozen primary HNSCC were collected through the Cooperative Human Tissue Network (CHTN). When patients presented to the CHTN institutions for surgery, informed consents to procure tumors were obtained; patients’ medical charts were reviewed to retrieve clinical and pathological data. Frozen tumors were analyzed for EGFR and Ron by immunoprecipitation followed by western blot (IPW) and immunohistochemistry (IHC). Only histologically confirmed, untreated HNSCC of the primary sites were included in the correlation analysis; samples with