Stabilization of HIF-1α and HIF-2α, up-regulation of MYCC and accumulation of stabilized p53 constitute hallmarks of CNS-PNET animal model

PLoS One. 2017 Mar 1;12(3):e0173106. doi: 10.1371/journal.pone.0173106. eCollection 2017.

Abstract

Recently, we described a new animal model of CNS primitive neuroectodermal tumors (CNS-PNET), which was generated by orthotopic transplantation of human Radial Glial (RG) cells into NOD-SCID mice's brain sub-ventricular zone. In the current study we conducted comprehensive RNA-Seq analyses to gain insights on the mechanisms underlying tumorigenesis in this mouse model of CNS-PNET. Here we show that the RNA-Seq profiles derived from these tumors cluster with those reported for patients' PNETs. Moreover, we found that (i) stabilization of HIF-1α and HIF-2α, which are involved in mediation of the hypoxic responses in the majority of cell types, (ii) up-regulation of MYCC, a key onco-protein whose dysregulation occurs in ~70% of human tumors, and (iii) accumulation of stabilized p53, which is commonly altered in human cancers, constitute hallmarks of our tumor model, and might represent the basis for CNS-PNET tumorigenesis in this model. We discuss the possibility that these three events might be interconnected. These results indicate that our model may prove invaluable to uncover the molecular events leading to MYCC and TP53 alterations, which would be of broader interest considering their relevance to many human malignancies. Lastly, this mouse model might prove useful for drug screening targeting MYCC and related members of its protein interaction network.

MeSH terms

  • Animals
  • Basic Helix-Loop-Helix Transcription Factors / genetics
  • Basic Helix-Loop-Helix Transcription Factors / metabolism*
  • Brain Neoplasms / genetics
  • Brain Neoplasms / metabolism*
  • Cells, Cultured
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism*
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID
  • Neuroectodermal Tumors, Primitive / genetics
  • Neuroectodermal Tumors, Primitive / metabolism*
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism*
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • Up-Regulation

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • Hif1a protein, mouse
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Proto-Oncogene Proteins c-myc
  • Tumor Suppressor Protein p53
  • endothelial PAS domain-containing protein 1