The potential of oncogene products as tumour markers.

This paper discusses the possibilities of using the altered expression of oncogenes and their products in neoplastic tissues as markers for the diagnosis, prognosis and monitoring of human malignant disease. Results from our studies of the c-myc oncogene and its product in human solid tumours, using DNA and RNA hybridization and a set of monoclonal antibodies (MCAs) raised against synthetic peptides, are presented. These illustrate three important principles. Firstly, the level of expression of the gene correlates closely with histological grading. Secondly, the increased expression of an oncogene in a tumour can be used as a marker for imaging with radiolabelled MCA. Thirdly, the detection of a 40,000 dalton serum protein, which is immunologically related to the p62c-myc oncoprotein, and its quantitative analysis in patients with cancer and normal controls, suggests that oncogene-related serum proteins may provide novel markers for monitoring tumour activity. These data support the view that the detailed analysis of oncogene expression has the potential to predict a tumour's behaviour and response to different therapeutic modalities.