Abstract 4415: Utilization of MBD-seq to elucidate differentially methylated regions in cfDNA across healthy and cancer patients

Abstract

Abstract 5-Methylcytosine (5-mC) is the most abundant epigenetic DNA modification in eukaryotes. The presence of 5-mC alters gene expression and genome metabolism, and its deregulation is associated with many human diseases. Cell-free DNA (cfDNA) released from apoptotic cells has recently gained attention, as mutations or epimutations (e.g. 5-mC variations) detected in cfDNA were shown to have high diagnostic potential to assess the presence, stage and outcome of several cancers. However, 5-mC detection in cfDNA remains a challenge as input material is often very scarce. MBD-Seq is a method that leverages the ability of Methyl-CpG-binding domain protein 2 (MBD2) to capture and detect highly methylated regions of DNA genome-wide. We evaluated MBD-Seq for the detection of aberrant methylation patterns in cfDNA from healthy and diseased patients. We found MBD-seq on cfDNA to be specific (over 100-fold mC:C detection ratio) and sensitive (5 ng of input cfDNA). Applying MBD-seq to samples from healthy vs colorectal and breast cancer patients showed striking differences in methylation of key tumor-associated genes. Hence, MBD-Seq can elucidate aberrant methylation patterns from cfDNA, highlighting its potential as a diagnostics tool for the detection of cancer. Citation Format: Camille Michelon, Brian Egan, Benjamin Delatte. Utilization of MBD-seq to elucidate differentially methylated regions in cfDNA across healthy and cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4415.