Increase of proliferating cell nuclear antigen (PCNA) expression in HPV-18 positive oral squamous cell carcinomas

Several studies have established a probable relationship between HPV infections and oral neoplasia. The present study analyze the importance of the integration of DNA of HPV type 18 on the proliferative capability of oral squamous cell carcinoma (OSCC) by the study of PCNA expression. Thirty seven patients with OSCC were studied. A complete clinical history and histopathological study was performed. DNA of HPV-18 was found in 7 of the 37 oral OSCCs (19.1%). PCNA expression appeared in 75.7% of OSCCs (28 cases). 9 OSCCs (24.3%) were completely negative, whereas 13 (35.1%), 8 (21.6%) and 7 (18.9%) show minimal, moderate and intense PCNA expression. 4 HPV-18 positive OSCCs showed a intense PCNA expression, 1 OSCC showed moderate PCNA expression, whereas 2 OCSSs showed minimal PCNA expression. Statistical correlations between PCNA expression and DNA HPV-18 amplification showed a more intense PCNA expression in HPV-18 positive OSCCs (p = 0.023). Further studies are needed to establish whether the increase of cellular proliferation induced by HPV-18 has prognostic consequences.