Overexpression of p53 and bcl-2 proteins and the presence of HPV infectionare independent events in head and neck cancer

The expression of p53 and bcl-2 proteins by immunohistochemistry and the id entification of human papillomavirus (HPV) infection by a non-isotopic poly merase chain reaction (PCR)-based method were investigated in 30 patients w ith head and neck cancer. Ten cases were HPV-positive (33%), mostly as doub le or multiple infections by high- or intermediate-risk types. Twenty-one p atients were p53-positive (70%), 9/10 with HPV-positive tumours and 12/20 w ith HPV-negative tumours; this difference was not statistically significant . Only four cases were bcl-2-positive, irrespective of the presence of eith er HPV or p53. No correlation was found between these biological factors an d tumour stage, differentiation grade, and alcohol or tobacco use. Our find ings indicate that p53 is involved in the majority of cases, bcl-2 is rare, and high-risk HPV could play a key role, especially in tumours of tongue a nd tonsil. In conclusion p53 and bcl-2 protein expression and the presence of HPV infection are independent events in these malignancies.