Epigenetically reprogrammed methylation landscape drives the DNA self-assembly and serves as a universal cancer biomarker
Menée à l'aide de lignées cellulaires de cancer mammaire, d'échantillons tumoraux et d'échantillons plasmatiques prélevés sur des patientes atteintes d'un cancer du sein, cette étude montre que l'évolution du profil de méthylation de l'ADN génomique lors de la carcinogenèse modifie les propriétés physico-chimiques de cet ADN, puis évalue la performance de tests électrochimiques ou colorimétriques exploitant cette modification pour détecter un cancer
Epigenetic reprogramming in cancer genomes creates a distinct methylation landscape encompassing clustered methylation at regulatory regions separated by large intergenic tracks of hypomethylated regions. This methylation landscape that we referred to as Methylscape is displayed by most cancer types, thus may serve as a universal cancer biomarker. To-date most research has focused on the biological consequences of DNA Methylscape changes whereas its impact on DNA physicochemical properties remains unexplored. Herein, we examine the effect of levels and genomic distribution of methylcytosines on the physicochemical properties of DNA to detect the Methylscape biomarker. We find that DNA polymeric behaviour is strongly affected by differential patterning of methylcytosine, leading to fundamental differences in DNA solvation and DNA-gold affinity between cancerous and normal genomes. We exploit these Methylscape differences to develop simple, highly sensitive and selective electrochemical or colorimetric one-step assays for the detection of cancer. These assays are quick, i.e., analysis time ≤10 minutes, and require minimal sample preparation and small DNA input.
Nature Communications , article en libre accès, 2018