An oncogenic MYB feedback loop drives alternate cell fates in adenoid cystic carcinoma

Nat Genet. 2016 Mar;48(3):265-72. doi: 10.1038/ng.3502. Epub 2016 Feb 1.

Abstract

Translocation events are frequent in cancer and may create chimeric fusions or 'regulatory rearrangements' that drive oncogene overexpression. Here we identify super-enhancer translocations that drive overexpression of the oncogenic transcription factor MYB as a recurrent theme in adenoid cystic carcinoma (ACC). Whole-genome sequencing data and chromatin maps highlight distinct chromosomal rearrangements that juxtapose super-enhancers to the MYB locus. Chromosome conformation capture confirms that the translocated enhancers interact with the MYB promoter. Remarkably, MYB protein binds to the translocated enhancers, creating a positive feedback loop that sustains its expression. MYB also binds enhancers that drive different regulatory programs in alternate cell lineages in ACC, cooperating with TP63 in myoepithelial cells and a Notch program in luminal epithelial cells. Bromodomain inhibitors slow tumor growth in ACC primagraft models in vivo. Thus, our study identifies super-enhancer translocations that drive MYB expression and provides insight into downstream MYB functions in alternate ACC lineages.

Publication types

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

MeSH terms

  • Carcinoma, Adenoid Cystic / genetics*
  • Carcinoma, Adenoid Cystic / pathology
  • Cell Line, Tumor
  • Cell Lineage / genetics
  • Chromatin / genetics
  • Enhancer Elements, Genetic*
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Oncogene Proteins v-myb / biosynthesis*
  • Oncogene Proteins v-myb / genetics
  • Oncogene Proteins, Fusion / biosynthesis
  • Oncogene Proteins, Fusion / genetics
  • Transcription Factors / biosynthesis
  • Translocation, Genetic*
  • Tumor Suppressor Proteins / biosynthesis

Substances

  • Chromatin
  • Oncogene Proteins v-myb
  • Oncogene Proteins, Fusion
  • TP63 protein, human
  • Transcription Factors
  • Tumor Suppressor Proteins