E2F5 and oropharynx squamous cell carcinoma: At the mRNA level, E2F5 expression was assessed through mRNA expression profiling, and at the protein level, expression was validated using immunohistochemistry (IHC) on tissue specimens, including 10 LSCC cases (laryngeal, hypopharyngeal, and oropharyngeal squamous cell carcinomas) and 10 non-LSCC controls (benign lesions such as mucoceles, hemangiomas, and polyps).