Human papillomaviruses and carcinogenesis: well-established and novel models.

•The HPV family includes over 200 members that infect skin and mucosal epithelia.•HR HPV types are linked to genital and upper respiratory tract cancers.•HR HPV E6 and E7 are essential for initiation and maintenance of carcinogenesis.•Beta HPV types cooperate with UV radiation in promoting skin cancer.•Beta HPV E6 and E7 may act only at an early stage of carcinogenesis.