Electrochemical Sensing of Cancer-related Global and Locus-specific DNA Methylation Events

Specific DNA methylation changes, both genome-wide and at specific gene loci in tissues and in biological fluids, have great potential as biomarkers for early detection, diagnosis, prognosis and therapeutic stratification of cancer. Although current classical methods are effective in studying DNA methylation patterns, they exhibit relatively low sensitivity and high false positive rates and require expensive instruments and complicated and time-consuming protocols. Here, we review basic information about relevance of DNA methylation in cancer, limitations of the conventional methodologies and promising features offered by electrochemical sensors to allow the determinations of methylated biomarkers in a straightforward, simple, sensitive, fast, portable and cost-effective way through highlighting selected examples described so far for sensing of cancer-related DNA methylation biomarkers. Major technical and biological challenges to be solved are also pointed out.