(A-J) Isotope-labeled carbon tracing experiment showing glucose and lactate metabolism in HBVPs. HBVPs were treated with isotope-labeled nutrients (­­CON: control, [13C6]-glu : 5mM [13C6]-glucose, [13C3]-Lac : 2mM [13C3]-Lactate, [13C3]-Lac-20 : 20mM [13C3]-Lactate in glucose free media) for 12hr and analyzed by a Q-exactive MS spectrometry. Barplots show relative fraction of unlabeled (M0) and labeled forms (M1~6) in various metabolites including A. Glucose, B. Lactate, C. Citrate, D. Aconitate, E. α-ketoglutarate (αKG), F. Succinate, G. Malate, H. Aspartate, I. Alanine, J. Glutamate. (n=3 from independent experiments.) 