Effect of human papillomavirus on cell cycle-related proteins p16INK4A, p21waf1/cip1, p53 and cyclin D1 in sinonasal inverted papilloma and laryngeal carcinoma. An in situ hybridization study.

Human papillomavirus (HPV) infection is implicated as an important risk factor in the development of head and neck cancers. Many studies focusing on the relationships between HPV infection and cell cycle proteins immunoexpression in laryngeal lesions have provided contradictory results. The aim of this study was to evaluate the relationships between HPV DNA presence and p16INK4a, p21waf1/cip1, p53 and cyclin D1 immunoexpression in heterogenous HPV-positive and HPV-negative groups of laryngeal cancers and inverted papillomas. The HPV DNA expression was detected using an in situ hybridization method and immunoexpression of p16INK4a, p21waf1/cip1, p53 and cyclin D1 using immunohistochemistry. The immunoexpression of p21waf1/ /cip1 and p53 proteins was lower in the HPV-positive group compared to the HPV-negative group, although only the difference of p53 staining was statistically significant. The immunoexpression of p16INK4a and cyclin D1 was significantly increased in the HPV-positive group compared to the HPV-negative group. The increased immunoexpression of p16INK4a and cyclin D1, and the lower immunoexpression of p21waf1/cip1 and p53 in the HPV-positive group compared to the HPV-negative group, supports the hypothesis that HPV may play an important role in cell cycle dysregulation.