Analysis of mutations in tumour supressor gene p53 in breast cancer patients from poznan area

Abstract

The p53 is transcriptional factor that enhances the rate of transcription of six or seven known genes which play important role in cell cycle regulation. The human p53 protein contains 393 amino acids and has been divided structurally and functionally into four domains. The p53 gene and its protein product have been studied since it became clear that slightly more than 50% of human cancers contain mutations in this gene. A study of mutational spectrum at the p53 gene are localized predominantly in the DNA-binding domain of the protein (exons 4–9). The nature of this changes is most commonly a missense mutation in one allele followed by a reduction to homozygosity, producing a faulty protein. Deletions or chain termination mutations are more rarely.

Mutations in p53 gene have been also found in breast cancer in 30–40% of cases. Kind of these mutations suggest that enviromental mutagens may play important role in arising of this type of cancer. It is observed that in West Poland breast cancer occures more frequently then in other areas of the country; the highest numbers of cases are found in GreatPoland still now for unknown reasons. In this work 48 cases of breast cancer were studied. 12 different mutations in p53 were found. This mutations were then compared with datebase catalogs containing mutations in p53. Only 3 from 12 found mutations are the same as reported in datebase. Nine of them were not observed before what may suggest that specific mutational spectrum in patients with breast cancer from GreatPoland exists. Futher studies involving greater number of cases are needed to confirm this observation.