CDP-choline accumulation in breast and colorectal cancer cells treated with a GSK-3-targeting inhibitor

PurposeGlycogen synthase kinase 3 (GSK3) is a key controlling element of many cellular processes including cell-cycle progression and recent studies suggest that GSK3 is a potential anticancer target. Changes in glucose metabolism associated with GSK3 inhibition may impact on lipid synthesis, whilst lipid metabolites can act as molecular response markers.MethodsHere, SKBr3 breast and HCT8 colorectal cancer cells were treated with the GSK3 inhibitor SB216763, and [C-14 (U)] glucose and [H-3] choline incorporation into lipids was determined. Cell extracts from treated cells were subject to P-31 NMR spectroscopy.ResultsSB216763 treatment decreased choline incorporation into lipids and caused an accumulation of CDP-choline which was accompanied by decreased conversion of glucose into lipid components.ConclusionSB216763 profoundly inhibits phospholipid synthesis in cancer cells which demonstrate accumulation of CDP-choline detectable by P-31 NMR spectroscopy. Metabolic changes in lipid metabolism present potential response markers to drugs targeting GSK3.