Cetuximab promotes anticancer drug toxicity in rhabdomyosarcomas with EGFR amplification in vitro

Oncol Rep. 2013 Sep;30(3):1081-6. doi: 10.3892/or.2013.2588. Epub 2013 Jul 4.

Abstract

Overexpression of human epidermal growth factor receptor (EGFR) has been detected in various tumors and is associated with poor outcomes. Combination treatment regimens with EGFR-targeting and cytotoxic agents are a potential therapeutic option for rhabdomyosarcoma (RMS) with EGFR amplification. We investigated the effects of combination treatment with actinomycin D and the EGFR-targeting agent cetuximab in 4 RMS cell lines. All 4 RMS cell lines expressed wild-type K-ras, and 2 of the 4 overexpressed EGFR, as determined by flow cytometry, real-time PCR and direct sequencing. Combination of cetuximab and actinomycin D was highly effective, synergistically inhibiting cell growth with a combination index of less than 1. Moreover, combination treatment with these two reagents increased the rate of apoptosis in EGFR-positive cells. Cetuximab has antitumor activity in EGFR-amplified RMS cells when combined with antitumor reagents, indicating that cetuximab is a potential therapeutic reagent for RMS with EGFR amplification.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal, Humanized / administration & dosage
  • Antineoplastic Combined Chemotherapy Protocols / pharmacology*
  • Apoptosis / drug effects*
  • Blotting, Western
  • Cell Proliferation / drug effects
  • Cetuximab
  • Dactinomycin / administration & dosage
  • Drug Synergism*
  • ErbB Receptors / genetics*
  • ErbB Receptors / metabolism
  • Flow Cytometry
  • Gene Amplification*
  • Humans
  • In Vitro Techniques
  • Mutation / genetics
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins p21(ras)
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Rhabdomyosarcoma / drug therapy*
  • Rhabdomyosarcoma / genetics
  • Rhabdomyosarcoma / pathology*
  • Tumor Cells, Cultured
  • ras Proteins / genetics
  • ras Proteins / metabolism

Substances

  • Antibodies, Monoclonal, Humanized
  • KRAS protein, human
  • Proto-Oncogene Proteins
  • RNA, Messenger
  • Dactinomycin
  • EGFR protein, human
  • ErbB Receptors
  • Proto-Oncogene Proteins p21(ras)
  • ras Proteins
  • Cetuximab