Preclinical evaluation of radiation and perifosine in a genetically and histologically accurate model of brainstem glioma.

Published

Journal Article

Brainstem gliomas (BSG) are a rare group of central nervous system tumors that arise mostly in children and usually portend a particularly poor prognosis. We report the development of a genetically engineered mouse model of BSG using the RCAS/tv-a system and its implementation in preclinical trials. Using immunohistochemistry, we found that platelet-derived growth factor (PDGF) receptor alpha is overexpressed in 67% of pediatric BSGs. Based on this observation, we induced low-grade BSGs by overexpressing PDGF-B in the posterior fossa of neonatal nestin tv-a mice. To generate high-grade BSGs, we overexpressed PDGF-B in combination with Ink4a-ARF loss, given that this locus is commonly lost in high-grade pediatric BSGs. We show that the likely cells of origin for these mouse BSGs exist on the floor of the fourth ventricle and cerebral aqueduct. Irradiation of these high-grade BSGs shows that although single doses of 2, 6, and 10 Gy significantly increased the percent of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive nuclei, only 6 and 10 Gy significantly induce cell cycle arrest. Perifosine, an inhibitor of AKT signaling, significantly induced TUNEL-positive nuclei in this high-grade BSG model, but in combination with 10 Gy, it did not significantly increase the percent of TUNEL-positive nuclei relative to 10 Gy alone at 6, 24, and 72 hours. Survival analysis showed that a single dose of 10 Gy significantly prolonged survival by 27% (P = 0.0002) but perifosine did not (P = 0.92). Perifosine + 10 Gy did not result in a significantly increased survival relative to 10 Gy alone (P = 0.23). This PDGF-induced BSG model can serve as a preclinical tool for the testing of novel agents.

Full Text

Cited Authors

  • Becher, OJ; Hambardzumyan, D; Walker, TR; Helmy, K; Nazarian, J; Albrecht, S; Hiner, RL; Gall, S; Huse, JT; Jabado, N; MacDonald, TJ; Holland, EC

Published Date

  • March 2, 2010

Published In

Volume / Issue

  • 70 / 6

Start / End Page

  • 2548 - 2557

PubMed ID

  • 20197468

Pubmed Central ID

  • 20197468

Electronic International Standard Serial Number (EISSN)

  • 1538-7445

International Standard Serial Number (ISSN)

  • 0008-5472

Digital Object Identifier (DOI)

  • 10.1158/0008-5472.CAN-09-2503

Language

  • eng