Pediatrics. The research was supported by the Cancer Prevention and Research Institute of
Texas (RP170114 and RP180778), the National Institutes of Health (R35 CA220449; U01
CA228608) and the Robert A. Welch Foundation (I-1733). A.T. was supported by the Else Kröner-
Forschungskolleg and the Leopoldina Fellowship Program (LPDS 2016-16) of the German
National Academy of Sciences. B.F. was supported by a postdoctoral fellowship from the
Canadian Institutes of Health Research (MFE 140911). B.S. and A.S. were supported by Ruth L.
Kirschstein National Research Service Award Postdoctoral Fellowships from the National
Heart, Lung, and Blood Institute (F32 HL139016-01) and the National Institute of Child Health
and Human Development (F32 HD096786-01). We thank A. Gross for mouse colony
management as well as N. Loof and the Moody Foundation Flow Cytometry Facility.
Author contributions A.T., R.J.D. and S.J.M. conceived the project, and designed and
interpreted experiments. A.T. performed most of the experiments. B.F., A.S., W.G. and R.J.D.
participated in the design, analysis and interpretation of isotope tracing and metabolomics
experiments. B.F., T.P.M. and R.J.D. developed methods for metabolomics and isotope tracing
in vivo. V.R. and J.M.U. helped A.T. to perform the in vivo tumorigenesis assays. J.M.U.
performed the melanoma cell migration experiments in culture. B.S., Z.G. and S.Y.K. helped to
design the CRISPR gene-targeting and MCT1 overexpression constructs, and generated the
constructs. D.S. and T.V. helped with the assessment and interpretation of MCT1 expression
patterns in patient specimens. T.P.M. and M.M. performed all of the mass spectrometric
analysis of metabolomic and isotope tracing specimens. M.M.M. performed the
immunofluorescence analysis of MCT1 expression. Z.Z. performed statistical analyses. A.T.,
B.F., R.J.D. and S.J.M. wrote the manuscript.Competing interests R.J.D. is an advisor for Agios Pharmaceuticals. S.J.M. is an advisor for
Frequency Therapeutics and Protein Fluidics
Additional information
Supplementary information is available for this paper at https://doi.org/10.1038/s41586-019-
1847-2.
Correspondence and requests for materials should be addressed to R.J.D. or S.J.M.
Peer review information Nature thanks John Cleveland, Markus Ralser and the other,
anonymous, reviewer(s) for their contribution to the peer review of this work.
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