Epstein-Barr Virus and Human Papillomavirus Co-Infections in Epithelial Carcinomas.

Co-infection of EBV and HPV is reported across head-and-neck, cervical, and breast carcinomas, though prevalence estimates vary due to regional differences, low viral copy numbers, and spatial heterogeneity of infected cells. Although more studies are needed, viral co-infection can influence the tumor immune microenvironment and replace mutations through viral oncogene activity or epigenetic changes in tumor progression. A few studies have shown that HPV-immortalization alters the outcome of EBV epithelial infections. In turn, EBV infection may enhance HPV integration and persistence. Thus, understanding the molecular and clinical contexts of co-infections, even if rare, may lead to context-specific interventions that include epigenetic therapy, therapeutic vaccines, and identification of biomarkers that can improve patient prognosis and therapeutic responses.