Head and neck cancer belongs to the most common types of cancer in both males and females with a mortality rate of approximately 50%. More than 90% of head and neck cancers are squamous cell carcinoma (HNSCC). Carcinogenesis of this disease involves activation of proto-oncogenes and inactivation of tumor suppressor genes. Among them, aberrations of p53 tumor suppressor gene are common events. The aim of this study was to assess the frequency of the tumor suppressor p53 aberrations in Czech population by using a functional test in yeast (FASAY) and by two immunochemical methods. We compared results of the methods and assessed the relationship between the presence of p53 aberration and some clinico-pathological parameters. The following observations were made: i) the accumulated p53 protein was detected in 33 of 50 tested samples (66%) by immunohistochemical analysis and in 27 of 49 tested samples (55.1%) by immunoblotting; ii) the presence of p53 mutation was detected in 36 of 50 tested samples (72%); iii) 6 of 36 p53 mutations detected by FASAY were temperature sensitive (16.7%); iv) 2 independent p53 mutations were found in at least 2 of the 36 positive cases; v) no statistically significant relationship was found between p53 aberration and overall survival.

Department of Anatomy and Pathology University Hospital Brno 625 00 Brno Czech Republic

High frequency of temperature-sensitive mutants of p53 in glioblastoma