Electrochemical biosensing strategies for DNA methylation analysis

Abstract

DNA methylation is one of the key epigenetic modifications of DNA that results from the enzymatic addition of a methyl group at the fifth carbon of the cytosine base. It plays a crucial role in cellular development, genomic stability and gene expression. Aberrant DNA methylation is responsible for the pathogenesis of many diseases including cancers. Over the past several decades, many methodologies have been developed to detect DNA methylation. These methodologies range from classical molecular biology and optical approaches, such as bisulfite sequencing, microarrays, quantitative real-time PCR, colorimetry, Raman spectroscopy to the more recent electrochemical approaches. Among these, electrochemical approaches offer sensitive, simple, specific, rapid, and cost-effective analysis of DNA methylation. Additionally, electrochemical methods are highly amenable to miniaturization and possess the potential to be multiplexed. In recent years, several reviews have provided information on the detection strategies of DNA methylation. However, to date, there is no comprehensive evaluation of electrochemical DNA methylation detection strategies. Herein, we address the recent developments of electrochemical DNA methylation detection approaches. Furthermore, we highlight the major technical and biological challenges involved in these strategies and provide suggestions for the future direction of this important field.

Graphene‐Oxide‐Loaded Superparamagnetic Iron Oxide Nanoparticles for Ultrasensitive Electrocatalytic Detection of MicroRNA

“…The heat‐released target miRNA was isolated by another magnetic separation step (See experimental for details) and directly adsorbed onto the GO/IO‐ modified SPCE using RNA‐ graphene oxide (GO) affinity interaction. We and others previously demonstrated a number of bioassays which rely on nucleic acid‐gold affinity interaction . Similar to the nucleic acid‐gold affinity interaction, direct physisorption of nucleotides (DNA/RNA) on graphene surface has been reported to be influenced by the polarizabilities of the individual nucleobases, where van der Wall (vdW) is considered to be the driving force for the adsorption process ,.…”

Rapid Electrochemical Assessment of Tumor Suppressor Gene Methylations in Raw Human Serum and Tumor Cells and Tissues Using Immunomagnetic Beads and Selective DNA Hybridization

“…Epigenetic modifications, such as specific DNA methylation changes, have great emerging potential as biomarkers for early detection, diagnosis, prognosis, and therapeutic stratification of cancer . DNA methylation, catalyzed by specific DNA methyltransferases (DNMTs), involves the covalent addition of a methyl group to the carbon‐5 position of a cytosine within CpG dinucleotides in clusters called CpG islands to yield 5‐methylcytosine (5‐mC), while keeping the original DNA sequences unchanged . 5‐mC hypermethylation by altered activity of DNMTs is closely associated with the transcription level of a gene and considered an early event in the development of cancer .…”

“…In this context, electrochemical biosensors offer unique advantages to overcome the aforementioned limitations for the detection of DNA methylation status . However, the electrochemical biosensors reported so far for this purpose, using both PCR and PCR independent approaches, have been mostly limited to synthesized DNA targets and scarcely explored in clinical samples.…”

Advances in Electrochemical (Bio)Sensing Targeting Epigenetic Modifications of Nucleic Acids

“…The rapidity with which this field moves has resulted in excellent reviews newly emerging, although they are mostly focused on electrochemical biosensors for DNA methylation [2][3][4][5] and/or miRNAs determination [6][7][8][9][10][11]. To provide the reader an updated overview of this highly relevant topic and the cutting-edge applications recently reported, this review article discusses the strategies and capabilities described in the last two years (from 2017 to the present) using electrochemical biosensing for the determination of epigenetic modifications in nucleic acids, including methylated bases (5-mC and 5-hmC in DNA and m6A in RNA), miRNAs and lncRNAs.…”