IDH2 and central nervous system cancer: To assess whether circulating miRNAs can mirror the mutation status of IDH genes, the serum-miRNome of glioma patients was analysed by small RNA-Sequencing in preoperative serum samples of a cohort of 37 glioma patients with different IDH mutation status (n = 27 IDH-wild type and n = 10 IDH-mutant), matched by gender and age (Table 1; Fig. 1a).