IDH2 and angioimmunoblastic T-cell lymphoma: Mutations in the metabolic enzymes isocitrate dehydrogenase (IDH) isoforms IDH1 and IDH2 are common in gliomas,16, 67 AML17, 68, 69 and angioimmunoblastic T-cell lymphoma.70 IDH1/2 are Nicotinamide Adenine Dinucleotide Phosphate (NADP)+-dependent metabolic enzymes that participate in the TCA cycle, catalyzing a two-step reaction for oxidative decarboxylation of isocitrate to α-KG.71 Mutations in IDH1/2 occur at substrate binding sites (IDH1: R132; IDH2: R140/172).