Differential regulation of the p73 cistrome by mammalian target of rapamycin reveals transcriptional programs of mesenchymal differentiation and tumorigenesis

Proc Natl Acad Sci U S A. 2011 Feb 1;108(5):2076-81. doi: 10.1073/pnas.1011936108. Epub 2011 Jan 18.

Abstract

The transcription factor p73 plays critical roles during development and tumorigenesis. It exhibits sequence identity and structural homology with p53, and can engage p53-like tumor-suppressive programs. However, different pathways regulate p53 and p73, and p73 is not mutated in human tumors. Therefore, p73 represents a therapeutic target, and there is a critical need to understand genes and noncoding RNAs regulated by p73 and how they change during treatment regimens. Here, we define the p73 genomic binding profile and demonstrate its modulation by rapamycin, an inhibitor of mammalian target of rapamycin (mTOR) and inducer of p73. Rapamycin selectively increased p73 occupancy at a subset of its binding sites. In addition, multiple determinants of p73 binding, activity, and function were evident, and were modulated by mTOR. We generated an mTOR-p73 signature that is enriched for p73 target genes and miRNAs that are involved in mesenchymal differentiation and tumorigenesis, can classify rhabdomyosarcomas by clinical subtype, and can predict patient outcome.

Publication types

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

MeSH terms

  • Cell Transformation, Neoplastic*
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Genome, Human
  • Humans
  • Mesoderm / pathology*
  • MicroRNAs / genetics
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism
  • Protein Binding
  • Rhabdomyosarcoma / classification
  • Rhabdomyosarcoma / genetics
  • Rhabdomyosarcoma / pathology
  • TOR Serine-Threonine Kinases / genetics*
  • Transcription, Genetic*
  • Tumor Protein p73
  • Tumor Suppressor Proteins / genetics*
  • Tumor Suppressor Proteins / metabolism

Substances

  • DNA-Binding Proteins
  • MicroRNAs
  • Nuclear Proteins
  • TP73 protein, human
  • Tumor Protein p73
  • Tumor Suppressor Proteins
  • TOR Serine-Threonine Kinases

Associated data

  • GEO/GSE15719