PTEN dosage is essential for neurofibroma development and malignant transformation Academic Article uri icon


MeSH Major

  • Cell Transformation, Neoplastic
  • Gene Dosage
  • Neurofibroma
  • PTEN Phosphohydrolase


  • Patients with neurofibromatosis type 1 (NF1) carry approximately a 10% lifetime risk of developing a malignant peripheral nerve sheath tumor (MPNST). Although the molecular mechanisms underlying NF1 to MPNST malignant transformation remain unclear, alterations of both the RAS/RAF/MAPK and PI3K/AKT/mTOR signaling pathways have been implicated. In a series of genetically engineered murine models, we perturbed RAS/RAF/MAPK or/and PTEN/PI3K/AKT pathway, individually or simultaneously, via conditional activation of K-ras oncogene or deletion of Nf1 or Pten tumor suppressor genes. Only K-Ras activation in combination with a single Pten allele deletion led to 100% penetrable development of NF lesions and subsequent progression to MPNST. Importantly, loss or decrease in PTEN expression was found in all murine MPNSTs and a majority of human NF1-associated MPNST lesions, suggesting that PTEN dosage and its controlled signaling pathways are critical for transformation of NFs to MPNST. Using noninvasive in vivo PET-CT imaging, we demonstrated that FDG can be used to identify the malignant transformation in both murine and human MPNSTs. Our data suggest that combined inhibition of RAS/RAF/MAPK and PTEN/PI3K/AKT pathways may be beneficial for patients with MPNST.

publication date

  • November 17, 2009



  • Academic Article



  • eng

PubMed Central ID

  • PMC2765459

Digital Object Identifier (DOI)

  • 10.1073/pnas.0910398106

PubMed ID

  • 19846776

Additional Document Info

start page

  • 19479

end page

  • 84


  • 106


  • 46