Head and neck squamous cell carcinoma (HNSCC), the sixth most prevalent cancer worldwide, remains a very difficult disease to treat and cure despite intensive investigation into molecular etiologies and tumor progression pathways. Due to public health efforts encouraging smoking cessation, the overall incidence of HNSCC has decreased in recent years in many countries. In contrast, the incidence of oropharyngeal squamous cell carcinoma (OPSCC) has increased significantly, and this subtype of HNSCC is commonly associated with human papillomavirus (HPV) infection. Moreover, individuals...