Lack of association between high-risk human papillomaviruses and oral squamous cell carcinoma in young Japanese patients.

BACKGROUND

Human papillomaviruses (HPV) may play an important role as one of the possible etiologies of oral squamous cell carcinoma (OSCC). The present study aimed to investigate the association between HPV and OSCC in young Japanese patients by examining the presence of HPV DNA and surrogate markers in OSCC tissues.

MATERIALS AND METHODS

Forty young patients with OSCC whose surgical specimens were available were analyzed and compared with 40 patients randomly recruited from a pool of patients aged >40 years. HPV DNA was detected using the polymerase chain reaction-based AMPLICOR(®) HPV test, and surrogate markers of HPV infection were analyzed using immunohistochemical techniques to detect p16(INK4a) and p53.

RESULTS

Only two (5%) young patients and one (2.5%) older patient were positive for HPV DNA. p16(INK4a) overexpression was identified in six (15%) young patients. p53 staining levels were not high in tissues of most young patients (27 patients, 67.5%). HPV DNA status did not significantly correlate with p16(INK4a) expression levels. Profiles of increased levels of p16(INK4a) expression with diminished levels of p53 staining were not associated with the presence of HPV DNA. The combined p53 with p16(INK4a) profiles were significantly correlated with alcohol consumption in younger patients (p=0.006).

CONCLUSIONS

RESULTS of the present study indicate that HPV is less likely to cause OSCC in young Japanese patients, and the p16(INK4a) expression level is not an appropriate surrogate marker for HPV infection in OSCC.