Limited Environmental Serine and Glycine Confer Brain Metastasis Sensitivity to PHGDH Inhibition

Cancer Discov. 2020 Sep;10(9):1352-1373. doi: 10.1158/2159-8290.CD-19-1228. Epub 2020 Jun 22.


A hallmark of metastasis is the adaptation of tumor cells to new environments. Metabolic constraints imposed by the serine and glycine-limited brain environment restrict metastatic tumor growth. How brain metastases overcome these growth-prohibitive conditions is poorly understood. Here, we demonstrate that 3-phosphoglycerate dehydrogenase (PHGDH), which catalyzes the rate-limiting step of glucose-derived serine synthesis, is a major determinant of brain metastasis in multiple human cancer types and preclinical models. Enhanced serine synthesis proved important for nucleotide production and cell proliferation in highly aggressive brain metastatic cells. In vivo, genetic suppression and pharmacologic inhibition of PHGDH attenuated brain metastasis, but not extracranial tumor growth, and improved overall survival in mice. These results reveal that extracellular amino acid availability determines serine synthesis pathway dependence, and suggest that PHGDH inhibitors may be useful in the treatment of brain metastasis. SIGNIFICANCE: Using proteomics, metabolomics, and multiple brain metastasis models, we demonstrate that the nutrient-limited environment of the brain potentiates brain metastasis susceptibility to serine synthesis inhibition. These findings underscore the importance of studying cancer metabolism in physiologically relevant contexts, and provide a rationale for using PHGDH inhibitors to treat brain metastasis.This article is highlighted in the In This Issue feature, p. 1241.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / therapeutic use*
  • Brain / metabolism
  • Brain / pathology*
  • Brain Neoplasms / drug therapy*
  • Brain Neoplasms / secondary
  • Cell Line, Tumor
  • Datasets as Topic
  • Drug Resistance, Neoplasm
  • Female
  • Gene Knockdown Techniques
  • Glycine / analysis
  • Glycine / metabolism
  • Humans
  • Metabolomics
  • Mice
  • Phosphoglycerate Dehydrogenase / antagonists & inhibitors*
  • Phosphoglycerate Dehydrogenase / genetics
  • Phosphoglycerate Dehydrogenase / metabolism
  • Proteomics
  • RNA-Seq
  • Serine / analysis
  • Serine / metabolism
  • Tumor Microenvironment / drug effects
  • Xenograft Model Antitumor Assays


  • Antineoplastic Agents
  • Serine
  • Phosphoglycerate Dehydrogenase
  • Glycine

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