Correlation between P53, P63 expression and HPV infection with staging and grading of oral squamous cell carcinoma

Squamous cell carcinoma is the eighth common cancer and forms 94% of oral malignancies. Nowadays, many molecular and genetic changes have been known to affect tumoral behavior which might be good for drug production and gene therapy. It has been known that mutated P53, overexpression of P63 as an oncogene and HPV infection are correlated with clinicopathological behavior of oral squamous cell carcinoma (OSCC) and it’s prognosis and overall survival rate. The aim of this study is to determine the correlation between the expression of P53, P63 and HPV infection with oral squamous cell carcinoma and it’s clinical staging and microscopical grading. Forty paraffin blocks with diagnosis of OSCC were collected from the pathology department, Shahid Beheshti School of Dentistry and the Department of general pathology, Taleghani hospital. Immunohistochemical staining was performed with antibodies against P53 and P63 and for detection of high risk types of HPV (HPV16, 18) polymerized chain reaction (PCR) was used. Spearman correlation test was used for data analyzing. In this analytical cross-sectional study, we found significant correlation between P53 total score and staging (P=0.0001) and P53 total score and grading (P=0.013). There was also significant correlation between P63 proportional score and grading (P=0.049). HPV16 also had significant correlation with P53 total score (P=0.003). The mean nuclear staining of P53 was 33.04±25.66% (CI=24.94-41.14) and P 63 was 39.25±19.35 (CI 33.13-45.37). HPV frequency was 40% (HPV 16=20% and HPV18=7.5%). There was no significant correlation between P63 and HPV infection (P>0.05). We concluded that P63 could be a diagnostic marker for grading of OSCC and P53 and P63 expression might have some role in progression of OSCC and its clinicopathological behavior. Presence of HPV especially HPV 16 may be regarded as a risk factor in OSCC.