Mutations in isocitrate dehydrogenases (IDHs) have a gainof-function effect leading to R(À)-2-hydroxyglutarate (R-2HG) accumulation. By using biochemical, structural and cellular assays, we show that either or both R-and S-2HG inhibit 2-oxoglutarate (2OG)-dependent oxygenases with varying potencies. Half-maximal inhibitory concentration (IC 50 ) values for the R-form of 2HG varied from approximately 25 lM for the histone N e -lysine demethylase JMJD2A to more than 5 mM for the hypoxia-inducible factor (HIF) prolyl hydroxylase. The results indicate that candidate oncogenic pathways in IDH-associated malignancy should include those that are regulated by other 2OG oxygenases than HIF hydroxylases, in particular those involving the regulation of histone methylation.

The non-essential amino acid serine supports several metabolic processes that are crucial for the growth and survival of proliferating cells, including protein, amino acid and glutathione synthesis. As an important one-carbon donor to the folate cycle, serine contributes to nucleotide synthesis, methylation reactions and the generation of NADPH for antioxidant defence. Many cancer cells are highly dependent on serine, a trait that provides several novel therapeutic opportunities, either through the inhibition of de novo serine synthesis or by limiting the availability or uptake of exogenous serine.

No abstract