We previously identified metabolic aberrations in phospholipid, energy and oxidative stress regulation in IDHm gliomas.10 Notably, despite a drop in the NADPH/NADP+ ratio, GSH levels were barely affected in IDH1m tumors, while enzymes related to cysteine metabolism and de novo GSH production such as cystathionine-β-synthase (CBS) and Glutamate-cysteine ligase catalytic subunit (GCLC) showed increased gene expression, suggesting that de novo GSH synthesis might be active in these tumors.10 The gene discussed is CBS; the disease is central nervous system cancer.