Human papillomavirus type 38 infection in oral squamous cell carcinomas.

In this study, 53 paraffin-embedded oral squamous cell carcinoma (OSCC) biopsy specimens were used. Human papillomavirus type 38 (HPV-38) infection was demonstrated in OSCCs using the PCR technique, DNA sequencing analysis, in situ hybridization, and immunohistochemical techniques. Additionally, the correlation between HPV-38 infection and expressions of proliferating cell nuclear antigens (PCNA) or p53 protein was analyzed immunohistochemically. Using consensus primers for the L1 region (L1-PCR), we identified 35 of 53 specimens (66%) as positive for HPV-38 DNA. Furthermore, specimens from patients over 60 years of age revealed a lower prevalence for the HPV-38 (56.7%) than did those below that age (78.3%). Immunohistochemically, positive stainings for PCNA and p53 protein were more frequently detected in HPV-38 positive OSCCs than HPV negative ones. These results indicate that HPV-38 positive OSCCs were higher in proliferative cellular activity than HPV negative ones. Moreover, the findings suggest that HPV-38 infection may cause malignant transformation of the oral mucosal epithelium.