Human Beta-papillomavirus infection and keratinocyte carcinomas.

Although the role of oncogenic human Alpha-papillomaviruses (HPVs) in the development of mucosal carcinomas at different body sites (eg cervix, anus, oropharynx) is fully recognized, a role for HPV in keratinocyte carcinomas (KCs; basal and squamous cell carcinomas) of the skin is not yet clear. KCs are the most common cancers in Caucasians, with the major risk factor being ultraviolet (UV) light exposure. A possible role for Beta-HPV types (BetaPV) in the development of KC was suggested several decades ago, supported by a number of epidemiological studies. Our current review summarizes the recent molecular and histopathological evidence in support of a causal association between BetaPV and the development of KC, and outlines the suspected synergistic effect of viral gene expression with UV radiation and immune suppression. Further insights into the molecular pathways and protein interactions used by BetaPV and the host cell is likely to extend our understanding of the role of BetaPV in KC.