Objective: To explore the correlation of human papillomavious (HPV) infection with expression of p53 and proliferating cell nuclear antigen (PCNA) in patients with different ethnicity in Xinjiang, China.
Methods: 166 biopsy specimens from 83 laryngeal squamous cell carcinomas (LSCC), 63 laryngeal papillomas (LP), and 20 laryngeal inflammatory polyps (LIP) were included in this study. HPV infection was determined by polymerase chain reaction (PCR) using specific types of HPV primers. Expression of p53 and PCNA was assessed using immunohistostaining.
Results: The frequency of HPV 6/11 was higher in LP (33.3%) than in LSCC (9.6%) (P<0.0005), whereas the frequency of HPV 16/18 was higher in LSCC (37.3%) than in LP (6.3%) (P<0.0005). Patients of the Han ethnic group with LSCC had a higher infection rate with HPV 6/11 or HPV 6/11 and HPV 16/18 coinfection than those of Uygur and Kazak ethnicity (P<0.05). Overexpression of p53 and PCNA were higher in LSCC (62.7%, 57.8%) than in LP (38%, 33.3%) (P<0.005, and P<0.005, respectively). That of p53 was not associated with lymph-node metastases and clinical stages, but overexpression of PCNA closely correlated with clinical stage.
Conclusions: These results strongly implicate HPV6/11 infection in the carcinogenesis of LSCC and LP, respectively. There was a higher coincidence of increased malignancy of laryngeal tumors with overexpression of p53 and PCNA. Overexpression of p53 may serve as an early risk marker for malignant transformation in HPV infected cells while the overexpression of PCNA may serve as a late marker for progression of LSCC.