Oral testing for high-risk human papillomavirus DNA and E6/E7 messenger RNA in healthy individuals at risk for oral infection

Background: Testing for oral high-risk human papillomavirus (HPV) DNA may be useful for identifying individuals at increased risk for HPV-driven oropharyngeal cancer (OPC). However, positivity for HPV DNA provides no information on the transforming potential of the infection. In contrast, the detection of high-risk HPV E6/E7 messenger RNA (mRNA) may help to identify clinically significant infections because of the indispensable role of E6/E7 viral oncoproteins in the carcinogenic process. Methods: Oral rinses were collected with a mouthwash from cancer-free individuals at increased risk for oral HPV infection. High-risk HPV DNA and mRNA were evaluated via the testing of the oral rinses with the Linear Array HPV genotyping test and the Aptima HPV assay, respectively. Results: Overall, 310 subjects with no clinical evidence of lesions of the oral cavity and oropharynx were included in the study. Thirty-three (10.6%) harbored high-risk HPV DNA in their oral rinse. These cases, together with 10 random samples negative for high-risk HPV DNA, were tested with the Aptima assay. A valid result was obtained for 41 of the 43 specimens (95.3%). Among the 31 cases that were positive for high-risk HPV DNA and had a valid Aptima result, 4 (12.9%) were positive for HPV mRNA. HPV mRNA was not detected in any of the samples negative for high-risk HPV DNA. Conclusions: HPV mRNA is detectable in oral rinses of cancer-free subjects. Oral HPV mRNA testing may be useful in the screening and/or early detection of HPV-driven OPC by possibly identifying active and transforming oral infections. The testing of individuals at increased risk for HPV-related OPC via simply and noninvasively collected oral specimens is an attractive option for future screening strategies.