Human papillomavirus infection in oral squamous cell carcinomas from Chilean patients

Human papillomavirus (HPV) is the causal agent of cervical, anogenital and a subset of oropharyngeal carcinomas. In addition, the role of HPV in oral carcinogenesis has been suggested, although the findings are inconclusive. In this study, using conventional polymerase chain reaction (PCR) and genotyping by specific PCR and DNA sequencing, we analyzed the HPV presence in 80 oral squamous cell carcinomas (OSCCs) from Chilean subjects. In addition, we determined the expression of p16, p53, pRb and Ki-67 using immunohistochemistry (IHC). The CDKN2A (p16) promoter methylation was evaluated using methylation-specific PCR (MSP). HPV sequences were found in 9/80 (11%) OSCCs. Non-statistically significant association with p53, pRb, Ki-67 and p16 levels were found (p=0.77; 0.29; 0.83; 0.21, respectively). HPV-16 and 18 were the most prevalent HPV genotypes in 8/9 (89%) OSCCs. In addition, CDKN2A (p16) was methylated in 39% of OSCCs. No association with HPV presence (p=0.917) was found. These results suggest that HPV positive OSCCs are entities that do not resemble the molecular alterations of HPV-associated tumors in a Chilean population. More studies are warranted to determine the role of HPV in OSCCs.