Nature - USA (2020-01-02)

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nature research | reporting summary

April 2018

Data

Policy information about availability of data

All manuscripts must include a data availability statement. This statement should provide the following information, where applicable:

• Accession codes, unique identifiers, or web links for publicly available datasets


• A list of figures that have associated raw data


• A description of any restrictions on data availability
  Data supporting the findings of this study are available within the article and its Supplementary Information files ore from the corresponding author on request.

Field-specific reporting

Please select the best fit for your research. If you are not sure, read the appropriate sections before making your selection.

Life sciences Behavioural & social sciences Ecological, evolutionary & environmental sciences

For a reference copy of the document with all sections, see nature.com/authors/policies/ReportingSummary-flat.pdf

Life sciences study design

All studies must disclose on these points even when the disclosure is negative.

Sample size Samples sizes were not pre-determined based on statistical power calculations but were based on our experience with these assays. For

assays in which variability is commonly high, we typically used n>10. For assays in which variability is commonly low, we typically used n<10.

Data exclusions No data were excluded; however, mice sometimes died during experiments, presumably due to the growth of metastatic tumors. In those

instances, data that had already been collected on the mice in interim analyses were included (such as subcutaneous tumor growth

measurements over time) even if it was not possible to perform the end-point analysis of metastatic disease burden (due to the premature

death of the mice).

Replication The experimental findings were reproduced in multiple independent experiments. The number of independent experiments and biological

replicates for each data panel is indicated in the figure panel itself, in the figure legends, and in the source data files. Data shown in the figures

represent the aggregate of all independent experiments in most cases. Data shown in a minority of panels are from a representative

experiment (e.g. for western blots) and in those cases the number of independent experiments that reproduced the finding is also indicated in

the figure legends. Tumor growth curves also show representative experiments because it is difficult to combine together tumor growth curve

data from multiple different experiments.

Randomization No formal randomization techniques were used; however, samples were allocated randomly to experiments and processed in an arbitrary

order.

Blinding During all isotope tracing experiments, the data were analyzed in a manner blinded to sample identity or treatment. A.T. performed all of the

infusions, collected tumor specimens, and performed mass spectrometry, then passed the de-identified data files to B.F. and A.S., who

analyzed the isotope tracing patterns. After the patterns had been analyzed for individual mice, the samples were re-identified so the results

could be interpreted.

Reporting for specific materials, systems and methods

Materials & experimental systems

n/a Involved in the study

Unique biological materials

Antibodies

Eukaryotic cell lines

Palaeontology

Animals and other organisms

Human research participants

Methods

n/a Involved in the study

ChIP-seq

Flow cytometry

MRI-based neuroimaging

Antibodies

Antibodies used The following antibodies have been used in this study: