Human papillomavirus infection and immunohistochemical expression of cell cycle proteins pRb, p53, and p16 INK4a in sinonasal diseases (Infectious Agents and Cancer)

Background: We aimed to clarify the possible role of human papillomavirus (HPV) infection in the malignant transformation of sinonasal inverted papilloma (IP). Methods: Subjects comprised 32 patients with chronic rhinosinusitis (CRS), 17 with IP, 5 with IP and squamous cell carcinoma (IP + SCC), and 16 with primary sinonasal SCC. HPV presence, viral loads, and physical status were investigated using polymerase chain reaction. Retinoblastoma (pRb), p53, and p16 INK4a gene products were investigated by immunohistochemistry. Results: HPV DNA was detected in 6.3 % of cases with CRS, 29.4 % with IP, 40 % with IP + SCC, and 25 % with SCC. IP cases had significantly higher HPV presence than CRS cases (p = 0.04). High-risk HPV-16 was the most frequently encountered subtype (10/13, 76.9 %). HPV-16 viral loads varied from 2.5 to 7953 E6 copies/50 ng genomic DNA. Patients in the SCC and IP + SCC groups had significantly higher viral loads than those in the IP and CRS groups (p