Titrimetric immunohistochemical evaluation of DNA hypomethylation in uterine tumours

Background: Global DNA hypomethylation is a well established feature of many common cancers. Aims: To establish a simple semi-quantitative, titrimetric immunohistochemical method in order to exploit this trait for prognostic purposes, in uterine cancers. Methods: A monoclonal antibody against 5-methylcytidine was used for immunohistochemical staining of methylated DNA in tumour cells. The degree of methylated DNA in the tumour tissue was visually compared and matched to that of normal tissues stained by serial decreasing concentrations of antibody to 5-methylcytidine. Results: Using this method a significant correlation was found between the histological stage and the reduction in DNA methylation in uterine adenocarcinoma (n = 39) and uterine squamous cell carcinoma (n = 23). Conclusions: A simple titrimetric immunohistochemical method has been developed for quantitative evaluation of ligands. This method should be further employed in follow-up studies, in order to establish the prognostic value of DNA hypomethylation in uterine cancer.