THE P53 TUMOR-SUPPRESSOR GENE AND ITS SIGNIFICANCE FOR DERMATOLOGY

The product of the p53 tumour suppressor gene is a sequence-specific DNA-binding protein that acts as a transcription factor and can inhibit transformation in vitro. Mutational inactivation of p53 is the most frequent genetic alteration found in human cancer. Point mutations of the p53 gene have been detected in about 50% of squamous cell carcinomas, basaliomas and cases of Bowen's disease. A significant portion of these mutations were CC --> TT or C --> T transitions suggestive of UV involvement in mutagenesis. Increased concentrations of p53 protein were immunohistochemically detected in cutaneous malignant melanomas, but p53 mutations are rare in this tumour.