ME1 and neoplasm: Moreover, lactate and glutamine support NADPH production via isocitrate dehydrogenase 1 (IDH1) and malic enzyme 1 (ME1), respectively, under glucose-deprived conditions, and ME1 can synergize with mitochondrial IDH2 to maintain antioxidant systems to support tumor growth and metastasis (Shao et al., 2020; Ying et al., 2021).