DNA methylation profiling for molecular classification of adult diffuse lower‑grade gliomas

DNA methylation profiling has become a powerful tool for neuro-oncology diagnostics. We investigated the value of using DNA methylation profiling to achieve molecular diagnosis in adult primary diffuse lower-grade gliomas according to WHO 2016 classification system of central nervous system tumors. We further evaluated the use of methylation profiling for improved molecular characterization of the tumors and identify prognostic differences beyond histological grade and molecular markers (IDH mutation and 1p/19q codeletion status). We investigated genome-wide DNA methylation profiles of 106 IDH-mutant gliomas using the Infinium MethylationEPIC BeadChip (Illumina, San Diego, USA) according to the manufacturer's instructions.