Global gene expression analysis of primary head and neck cancer cases

This study addressed the assumption that in addition to somatic mutations epigenetic silencing of cancer-related genes by promoter hyper-methylation is a common event in head and neck cancer. A multi-scale omics approach based on whole-exome sequencing, global DNA methylation and gene expression profiling data derived from tumor samples of the HIPO-HNC cohort was conducted and new findings were confirmed with data from TCGA-HNC. Results provide experimental evidence that the ryanodine receptor 2 (RYR2) exhibits variable promoter methylation and expression in both tumor samples and HNSCC cell lines. Moreover, immunohistochemical staining of tissue sections unraveled a gradual loss of RYR2 expression from normal mucosa via dysplastic lesions to cancer, and indicated that reduced RYR2 expression in adjacent tissue and precancer lesions might serve as a risk factor for unfavorable prognosis and upcoming malignant conversion. Total RNA obtained from primary head and neck cancer of the HIPO-HNC cohort