Gene expression profiling of African American vs European American HPV-negative oropharyngeal squamous cell carcinomas

Head and neck cancer (HNC) is the fifth most common malignancy worldwide with an annual mortality rate of 200,000. About 90% of HNC can be classified as head and neck squamous cell carcinomas (HNSCC), of which approximately 75% are attributed to alcohol and tobacco consumption and 25% are associated with human papillomavirus (HPV), predominantly HPV16. HPV-associated OPC have better prognosis and a more favorable response to therapy as compared to HPV-negative tumors. Differences in risk factors, age of presentation, clinical behavior and gene expression profiles indicate that HPV-positive and HPV-negative tumors develop via different molecular mechanisms and are biologically distinct. African American (AA) males have a higher incidence of HNC than any other racial/gender group, and a mortality rate almost three-fold that observed in European American (EA) males. Overall, AA patients tend to present with more HPV-negative OPC and have worse prognosis as compared to both HPV-positive and HPV-negative HNSCC in EA patients. Despite the unveiling of differential gene expression patterns, genetic and epigenetic profiles and the compilation of a mutational landscape along with preliminary TCGA data of HPV-related and unrelated HNC, the molecular determinants of the racial disparity in HNC are yet to be identified. This study aimed to compare the gene expression profiles of HPV-negative HNSCC from AA and EA patients, and determine their biological differences. ANALYSIS 2: Two-condition, on-color experiment: African American (AA) vs European American (EA) HPV-negative oropharyngeal squamous cell carcinomas. Biological replicates: 8 African American and 8 European American.