General primer-mediated polymerase chain reaction for simultaneous detection and typing of human papillomavirus DNA in laryngeal squamous cell carcinomas.

The aim of this study was to investigate the prevalence of different human papillomavirus (HPV) types in laryngeal squamous cell carcinomas using general primer-mediated polymerase chain reaction (PCR). Tumour sections from 42 patients with laryngeal carcinomas were investigated. For HPV DNA amplification, consensus primers were used which were directed to the L1 coding region of the HPV genome. Analysis of the PCR products was done using 2% agarose gel electrophoresis followed by restriction enzyme analysis to identify different HPV types. Amplification of the human TGF-beta 1 DNA was successfully performed in 36/42 (85.7%) of samples confirming the presence of sufficient DNA for viral amplification. HPV DNA was detected in 8/36 (22.2%) of the tumours examined (three HPV-6, two HPV-16, one HPV-11, two unknown HPV types). HPV DNA was not detected in any of the non-neoplastic laryngeal mucosa which was used as control (n = 15). Fifty per cent of women had HPV-positive tumours compared with 8% of men (chi2 = 5.8, P < 0.05). Our data indicate that while the overall prevalence of HPV in laryngeal carcinomas is fairly high (22.2%), the frequency of high-risk types (HPV-16 & HPV-18) is low (5.5%). HPV probably acts as a promoter in the multistep process of carcinogenesis in squamous mucosal cells of the larynx.