Zip folder with 8 Excel files containing the raw measurements of main RAW_Figure_1 (1A-C, G-I - Spectra were zero- and first-order phase corrected, and the peaks modelled with the AMARES toolbox), RAW_Figure_2 (Apparent malate production rates were calculated between 0 and 20 min following fumarate administration and plotted against the tumor fumarate concentration at 20 minutes. The curves can be fitted to the Michaelis-Menten equation to obtain an estimate of Km and Vmax), RAW_Figure_3 (3M,3N - Images were analyzed using a CytoNuclear v1.6 algorithm on HALO v3.0.311.293. Shown are percentage of positive cells), RAW_Figure_4 (4A-L - Pearson correlation analysis of histological markers of cell death, CC3 (A – F) and TUNEL (G – L) % positive cells, with the malate/fumarate ratio and malate concentration (mM) obtained by summing the spectra between 20 and 60 min after fumarate injection.) Supplementary_Figure_1 (S1A-C, G-I - Spectra were zero- and first-order phase corrected, and the peaks modelled with the AMARES toolbox, shown are ²H MR spectroscopic measurements of labeled fumarate, malate and water concentrations in MDA-MB-231 tumors following injection of increasing concentrations of [2,3-²H₂]fumarate), RAW_Supplementary_Figure 3 (Tumor malate concentrations before and after treatment with 0.1, 0.4, and 0.8 mg/kg MEDI3039 between 20 and 60 minutes after injecting increasing fumarate concentrations (0.1, 0.3 and 0.5 g/kg)), RAW_Supplementary_Figure_4 (S4A-C - Ratios were obtained by summing the fumarate and malate signals between 20 and 60 min after injection of [2,3-²H₂]fumarate at 0.1, 0.3 and 0.5 g/kg. The malate/fumarate ratio is the dependent variable and was assessed at increasing concentrations of fumarate at each of the MEDI3039 drug concentrations.), Supplementary_Figure_5 (S5A-C - Representative time course data for labeled fumarate, malate and water concentrations with the corresponding coefficients of variance, following injection of increasing concentrations of [2,3-²H₂]fumarate.)