An LXR agonist promotes glioblastoma cell death through inhibition of an EGFR/AKT/SREBP-1/LDLR-dependent pathway. Academic Article uri icon

Overview

abstract

  • Glioblastoma (GBM) is the most common malignant primary brain tumor of adults and one of the most lethal of all cancers. Epidermal growth factor receptor (EGFR) mutations (EGFRvIII) and phosphoinositide 3-kinase (PI3K) hyperactivation are common in GBM, promoting tumor growth and survival, including through sterol regulatory element-binding protein 1 (SREBP-1)-dependent lipogenesis. The role of cholesterol metabolism in GBM pathogenesis, its association with EGFR/PI3K signaling, and its potential therapeutic targetability are unknown. In our investigation, studies of GBM cell lines, xenograft models, and GBM clinical samples, including those from patients treated with the EGFR tyrosine kinase inhibitor lapatinib, uncovered an EGFRvIII-activated, PI3K/SREBP-1-dependent tumor survival pathway through the low-density lipoprotein receptor (LDLR). Targeting LDLR with the liver X receptor (LXR) agonist GW3965 caused inducible degrader of LDLR (IDOL)-mediated LDLR degradation and increased expression of the ABCA1 cholesterol efflux transporter, potently promoting tumor cell death in an in vivo GBM model. These results show that EGFRvIII can promote tumor survival through PI3K/SREBP-1-dependent upregulation of LDLR and suggest a role for LXR agonists in the treatment of GBM patients.

publication date

  • September 15, 2011

Research

keywords

  • Brain Neoplasms
  • Cell Death
  • ErbB Receptors
  • Glioblastoma
  • Orphan Nuclear Receptors
  • Proto-Oncogene Proteins c-akt
  • Receptors, LDL
  • Signal Transduction
  • Sterol Regulatory Element Binding Protein 1

Identity

PubMed Central ID

  • PMC3207317

Scopus Document Identifier

  • 84861101004

Digital Object Identifier (DOI)

  • 10.1158/2159-8290.CD-11-0102

PubMed ID

  • 22059152

Additional Document Info

volume

  • 1

issue

  • 5