Gene silencing for epidermal growth factor receptor variant III induces cell-specific cytotoxicity

Farnaz Yamoutpour, Vidya Bodempudi, Shay E. Park, Weihong Pan, Mary Jean Mauzy, Robert A. Kratzke, Arkadiusz Dudek, David A. Potter, Richard A. Woo, Donald M. O'Rourke, Donald J. Tindall, Faris Farassati

Research output: Contribution to journalArticlepeer-review

27 Scopus citations

Abstract

Epidermal growth factor receptor variant III (EGFRvIII) is a constitutively active mutant form of EGFR that is expressed in 40% to 50% of gliomas and several other malignancies. Here, we describe the therapeutic effects of silencing EGFRvIII on glioma cell lines in vitro and in vivo. A small interfering RNA molecule against EGFRvIII was introduced into EGFRvIII-expressing glioma cells (U87Δ) by electroporation resulting in complete inhibition of expression of EGFRvIII as early as 48 h post-treatment. During EGFRvIII silencing, a decrease in the proliferation and invasiveness of U87Δ cells was accompanied by an increase in apoptosis (P < 0.05). Notably, EGFRvIII silencing inhibited the signal transduction machinery downstream of EGFRvIII as evidenced by decreases in the activated levels of Ras and extracellular signal-regulated kinase. A lentivirus capable of expressing anti-EGFRvIII short hairpin RNA was also able to achieve progressive silencing of EGFRvIII in U87Δ cells in addition to inhibiting cell proliferation, invasiveness, and colony formation in a significant manner (P < 0.05). Silencing EGFRvIII in U87Δ cultures with this virus reduced the expression of factors involved in epithelial-mesenchymal transition including N-cadherin, β-catenin, Snail, Slug, and paxillin but not E-cadherin. The anti-EGFRvIII lentivirus also affected the cell cycle progression of U87Δ cells with a decrease in G1 and increase in S and G2 fractions. In an in vivo model, tumor growth was completely inhibited in severe combined immunodeficient mice (n = 10) injected s.c. with U87Δ cells treated with the anti-EGFRvIII lentivirus (P = 0.005). We conclude that gene specific silencing of EGFRvIII is a promising strategy for treating cancers that contain this mutated receptor.

Original languageEnglish (US)
Pages (from-to)3586-3597
Number of pages12
JournalMolecular cancer therapeutics
Volume7
Issue number11
DOIs
StatePublished - Nov 1 2008

ASJC Scopus subject areas

  • Oncology
  • Cancer Research

Fingerprint

Dive into the research topics of 'Gene silencing for epidermal growth factor receptor variant III induces cell-specific cytotoxicity'. Together they form a unique fingerprint.

Cite this