PGD and neoplasm: Certain downstream targets of the Keap1-Nrf2 pathway such as the malic enzyme 1 (ME1), involved in NADPH production, displayed elevated mRNA levels in the tumor ρ0 cell lines (S3 Fig) while other targets such as glucose-6-phosphate dehydrogenase (G6PD), phosphogluconate dehydrogenase (PGD), NAD(P)H quinone dehydrogenase 1 (NQO1, involved in quinone detoxification) and glutathione peroxidase 1 (GPX1) did not show altered mRNA expression levels for the ρ0 cells (S3 Fig).