Third, a molecular analysis of aggressive behavior in HPV tumors revealed an enriched signature of apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like (APOBEC), in HPV-infected head–neck cancers, causing DNA damage due to the APOBEC3A/B activity that occurs in response to viral infections [31]. The gene discussed is APOBEC3A; the disease is head and neck cancer.