IDH1 and leukemia: Moreover, FTO plays a role in response to all-trans-retinoic acid (ATRA) and, interestingly, D-2-hydroxyglutarate (D2-HG) (the metabolite accumulated in isocitrate dehydrogenase 1 and 2 (IDH1/2)-mutant leukemias (20% of AMLs)) functions as an inhibitor of FTO demethylase, meaning that FTO expression is context-dependent and has to be interpreted according to IDH mutational status [81,82].