Tracer-based metabolic NMR-based flux analysis in a leukaemia cell line

High levels of reactive oxygen species (ROS) have a profound impact on acute myeloid leukaemia (AML) cells and can be used to specifically target AML cells with novel therapies. We have previously shown how the combination of two redeployed drugs (BaP), the contraceptive steroid medroxyprogesterone (MPA) and the lipid- regulating drug bezafibrate (BEZ) exert anti-leukaemic effects by producing ROS. Here we report a 13C-tracer-based NMR metabolic study to understand how drugs are working in K562 AML cells. Our study shows that [1,2-13C]glucose is incorporated into riboses, showing oxidative and non-oxidative pentose phosphate pathway activity alongside lactate production. There is little label incorporation into the TCA cycle from glucose, but much greater incorporations arising from [3-13C]glutamine. BaP treatment decreases the label incorporation from both glucose and glutamine for α-ketoglutarate and increased that for succinate consistent with ROS-mediated conversion of α-ketoglutarate to succinate. Most interestingly, BaP treatment drastically reduced the production of several pyrimidine synthesis intermediates.