Epidemiology of HPV in head and neck cancer: Variant strains, discrete protein function

Human papillomavirus (HPV) infection has emerged as a major causative agent for cancers of the head and neck. HPV-positive cancers of the oropharynx are associated with better survival rates than HPV-negative cancers of the oropharynx, which appears likely to be associated with differences in the biology of the two diseases. We will discuss the role of HPV-encoded proteins in host infection and carcinogenesis. HPV infection is increasing worldwide, with recent data showing a dramatic increase in HPV-associated oropharyngeal head and neck cancer incidence, and contrasting infection rates in developed and developing nations. Finally, we will review the emerging biology of intratypic variants of HPV, with different variants associated with different potential for malignancy, and suggest potential areas of further study.