Methylation specific enzyme-linked oligonucleotide assays (MS-ELONA) for ultrasensitive DNA methylation analysis

Methylation of the promoter region of cancer related genes plays a crucial role in the occurrence and devel-opment of cancer, and the degree of methylation has great potential for the early cancer diagnosis. At present, the technology used to quantify DNA methylation is mainly based on the DNA sequencing which are time-consuming and high-cost in the relating application. We have developed an ultrasensitive method of methylation specific enzyme-linked oligonucleotide assays (MS-ELONA) to detect and quantify the level of DNA methylation. We could detect as little as 2 pg of methylated DNA in the 100000-fold excess of unmethylated genes, and discriminate prostate cancer from benign prostatic hyperplasia (BPH) and control with serum samples. We also demonstrate the reversibility of DNA methylation modification by treatment with demethylation drugs. With 16-channel electrochemical work station, our research reveals a simple and inexpensive method to quantify the methylation level of specially appointed genes, and have the potential to be applied in the clinical research.

Automated summary

Methylation of cancer related genes' promoter region is crucial in cancer occurrence and development, with high potential for early diagnosis. Current quantification methods are time-consuming and expensive. We developed a ultrasensitive MS-ELONA method to detect and quantify DNA methylation level, with the ability to detect as little as 2 pg of methylated DNA in excess unmethylated genes, and differentiate prostate cancer from BPH and control samples. Our research demonstrates a simple and inexpensive method to quantify methylation levels of specific genes, with potential for clinical applications.