IDH2 and cancer: Oncogenic mutations in the IDH1 and IDH2 enzymes in cancer facilitate the biochemical reaction transforming alpha-ketoglutarate (α-KG) into the oncometabolite 2-hydroxyglutarate (2-HG)—the overproduction of 2-HG results in metabolic abnormalities, including significantly diminished basal levels of NAD+ [77].