ABSTRACT
BACKGROUND: Although human papillomavirus (HPV) infection has been shown to be a significant carcinogen in cervical squamous cell carcinoma (SCC), its significance in oral SCC remains unclear. METHODS: We developed highly sensitive detection methods for HPV to elucidate the prevalence and localization of HPV in paraffin sections from human oral SCC using modified in situ polymerase chain reaction (PCR) and in situ hybridization AT tailing (ISH-AT). Analyses revealed a high prevalence of several HPV types (HPV-16, -18, -22, -38 and -70) under optimal conditions. The ISH-AT method can be used as an alternative to in situ PCR. RESULTS: Various staining patterns were observed in the 20 cases examined, and HPV-positive cells were localized within the surface epithelium as well as in neoplastic cells. We demonstrated that HPV-DNA could be detected in paraffin sections using either the method of in situ PCR or ISH, providing an appropriate primer and probe are used. CONCLUSION: These results suggest that HPV infection could be one of several risk factors being involved in oral SCC.