The use of biomarkers to study pathogenesis and mechanisms of cancer: oesophagus and skin cancer as models.

Recent advances in molecular biology have made it possible to use genetic alterations associated with cancer as biomarkers to study the pathogenesis and mechanisms of cancer. However, the lessons that can be drawn from the analysis of alterations in a particular cancer gene are extremely dependent upon the biological context in which they arise. In this article, we discuss the biological significance of alterations in the p53 tumour suppressor gene in cancers of the oesophagus and of the skin. In both tissues, different forms of cancer occur at high frequency (squamous-cell carcinoma and adenocarcinoma in the oesophagus; squamous-cell carcinoma, basal-cell carcinoma and melanoma in the skin). We show that specific patterns of p53 alteration occur in these various cancers and that analysis of these alterations is useful to make inferences about the etiopathogenesis of cancers of the oesophagus and of the skin.