Human papillomavirus infections in lung cancer. Detection of E6 and E7 transcripts and review of the literature

Lung cancer is the leading cause of cancer related death in Western countries. Several factors have been implicated in its aetiology: cigarette smoking, environmental pollution, asbestos and genetic factors. The possible involvement of human papillomavirus (HPV) in bronchial squamous cell lesions was first suggested in 1979 by Syrjänen. Since then, several studies have confirmed the presence of HPV DNA in about 20% of lung cancer cases examined, with HPV16 and 18 as the two most frequently found oncogenic viral types. More recently, these data have been supported by the detection of E6 and E7 transcripts in HPV-positive lung cancer cases, reinforcing the hypothesis that oncogenic HPVs could act as cofactors in bronchial carcinogenesis. This published literature is briefly reviewed and new data of the authors on detection of E6 and E7 transcripts in lung cancer samples are presented.