P226 Lack of Exon 19 and 21 EGFR Mutations in Squamous Cell Head and Neck Cancer Specimens and Cell Lines

Abstract

termined the global gene expression profiles of primary OSCCs and identified a subset of deregulated genes that correlated with more advanced-stage tumors. A subset of these genes are involved in signal transduction genetic networks. Our objective is thus to examine the expression of these genes in OSCCs. Design: Tissue samples were obtained at the time of surgery from the Toronto General Hospital and snap frozen in liquid nitrogen for RNA extraction. Quantitative real-time reverse-transcriptase polymerase chain reaction using the ABI PRISM 7700 Sequence Detection System and the Sequence Detection System software (PE Applied Biosystems, Foster City, Calif) was used for relative quantification of gene expression. Data analysis was performed using the Delta Delta Ct method. Patients: Sixty-eight patients with OSCC who had surgery as primary treatment were included in this study. Results: Deregulated expression of -catenin, a gene involved in maintaining cell-to-cell adhesion in normal cells mediating the Wnt signal transduction pathway was detected. WISP1, WISP2, TCF4, and LEF1 genes are also associated with the Wnt pathway and were thus included in this study to further investigate whether the Wnt/b-catenin pathway is deregulated in head and neck cancer. Conclusion: Deregulated expression of genes involved the Wnt/beta-catenin pathway in OSCC.