Based on these findings, as well as the established role of A3B activity in HNSCC, we investigated the immunohistochemical expression of the PKCα, NF-κΒ, and A3B proteins in a cohort of non-HPV related human oral SSC (OSSC) and oropharyngeal SCC (OPSCC). The gene discussed is APOBEC3B; the disease is head and neck squamous cell carcinoma.