Secreted protein profile from HepG2 cells incubated by S(-) and R(+) enantiomers of chiral drug warfarin - An analysis in cell-based system and clinical samples.

warfarin is a commonly prescribed oral anticoagulant with narrow therapeutic index. It interferes with the vitamin K cycle to achieve anti-coagulating effects. Warfarin has two enantiomers, S(-) and R(+) and undergoes stereoselective metabolism, with the S(-) enantiomer being more effective. Our target is to discover the biological differences of the two enantiomers for better warfarin therapy. we reported the extracellular protein profile in HepG2 cells incubated with S(-) and R(+) warfarin, using iTRAQ-coupled 2-D LC-MS/MS. In addition, clinical sera from 30 patients taken warfarin were also analyzed by the same method as a long-term batch. in cell line batch in samples incubated with S(-) and R(+) warfarin alone, inter-α-trypsin inhibitor heavy chain H4, apolipoprotein A-I and α-2-HS-glycoprotein showed variations in cells incubated with S(-) warfarin and R(+) warfarin. For other proteins like α-2-macroglobulin and Fibrinogen γ chain, the expressions each were found to be the same in cells incubated with either S(-) or R(+) warfarin. Clinical results showed the same trends for protein ratio changes. our results indicated that those proteins may interfere with blood coagulation process, as well as contribute to the warfarin's side-effect response. Taken together, our findings provided molecular evidence on a comprehensive protein profile on warfarin-cell interaction which may shed new lights on future improvement of warfarin therapy.