STAT3-low tumors, in contrast, comprise mostly of low-grade gliomas (LGGs), and the proneural molecular subtype with enrichment of 1p/19q co-deletion and IDH-Mut (mutant) status, representing tumors of better prognosis and responsiveness to current chemotherapy (Fig. 1b, and additional clinical database TCGA, Supplementary Fig. 2a)20. This evidence concerns the gene IDH2 and central nervous system cancer.