MYC is a positive regulator of choline metabolism and impedes mitophagy-dependent necroptosis in diffuse large B-cell lymphoma

Blood Cancer J. 2017 Jul 7;7(7):e0. doi: 10.1038/bcj.2017.61.

Abstract

The activation of oncogenes can reprogram tumor cell metabolism. Here, in diffuse large B-cell lymphoma (DLBCL), serum metabolomic analysis revealed that oncogenic MYC could induce aberrant choline metabolism by transcriptionally activating the key enzyme phosphate cytidylyltransferase 1 choline-α (PCYT1A). In B-lymphoma cells, as a consequence of PCYT1A upregulation, MYC impeded lymphoma cells undergo a mitophagy-dependent necroptosis. In DLBCL patients, overexpression of PCYT1A was in parallel with an increase in tumor MYC, as well as a decrease in serum choline metabolite phosphatidylcholine levels and an International Prognostic Index, indicating intermediate-high or high risk. Both in vitro and in vivo, lipid-lowering alkaloid berberine (BBR) exhibited an anti-lymphoma activity through inhibiting MYC-driven downstream PCYT1A expression and inducing mitophagy-dependent necroptosis. Collectively, PCYT1A was upregulated by MYC, which resulted in the induction of aberrant choline metabolism and the inhibition of B-lymphoma cell necroptosis. Referred as a biomarker for DLBCL progression, PCYT1A can be targeted by BBR, providing a potential lipid-modifying strategy in treating MYC-High lymphoma.

MeSH terms

  • Berberine / pharmacology
  • Cell Line, Tumor
  • Choline / biosynthesis*
  • Choline / genetics
  • Choline-Phosphate Cytidylyltransferase / genetics
  • Choline-Phosphate Cytidylyltransferase / metabolism
  • Humans
  • Lymphoma, Large B-Cell, Diffuse / genetics
  • Lymphoma, Large B-Cell, Diffuse / metabolism*
  • Lymphoma, Large B-Cell, Diffuse / pathology
  • Mitophagy*
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism*

Substances

  • MYC protein, human
  • Proto-Oncogene Proteins c-myc
  • Berberine
  • Choline-Phosphate Cytidylyltransferase
  • PCYT1A protein, human
  • Choline