Antitumor mechanisms of systemically administered epidermal growth factor receptor antisense oligonucleotides in combination with docetaxel in squamous cell carcinoma of the head and neck

Mol Pharmacol. 2008 Mar;73(3):627-38. doi: 10.1124/mol.107.041160. Epub 2007 Nov 19.

Abstract

Squamous cell carcinoma of the head and neck (SCCHN) is one of the most common malignancies worldwide, with low 5-year survival rates. Current strategies that block epidermal growth factor receptor (EGFR) have limited effects when administered as single agents. Targeting EGFR via intratumoral administration of phosphorothioate-modified antisense oligonucleotides has antitumor efficacy in xenograft models of SCCHN. Because intratumoral delivery of therapeutic agents has limited clinical application, the present study was undertaken to examine the therapeutic mechanisms of systemically delivered phosphorothioate-modified EGFR antisense oligonucleotides alone, or in combination with docetaxel, in a SCCHN xenograft model. EGFR antisense oligonucleotides were administered at 5 mg/kg i.p. daily in athymic mice bearing 1483 human SCCHN xenografts alone or in combination with docetaxel at 2.5 mg/kg i.p. once a week for 4 weeks. Administration of EGFR antisense oligonucleotides in combination with docetaxel improved antitumor efficacy and resulted in lower expression levels of EGFR, fewer proliferating cells, and more apoptotic cells in the tumors compared with controls. Systemic administration of phosphorothioated EGFR antisense oligonucleotides for 30 days increased the retention of docetaxel in the tumor by approximately 4-fold compared with tumors treated with docetaxel alone or docetaxel and EGFR sense oligonucleotides (P < 0.05). Combination of EGFR antisense oligonucleotides with low doses of docetaxel has antitumor efficacy, and it may be an effective treatment strategy for SCCHN.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antineoplastic Agents / administration & dosage
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / blood
  • Antineoplastic Agents / pharmacokinetics
  • Antineoplastic Agents / therapeutic use*
  • Apoptosis / drug effects
  • Carcinoma, Squamous Cell / drug therapy*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Docetaxel
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Drug Therapy, Combination
  • ErbB Receptors / metabolism*
  • Female
  • Head and Neck Neoplasms / drug therapy*
  • Humans
  • Immunohistochemistry
  • Injections, Intraperitoneal
  • Mice
  • Mice, Nude
  • Models, Biological
  • Oligonucleotides, Antisense / administration & dosage
  • Oligonucleotides, Antisense / adverse effects
  • Oligonucleotides, Antisense / pharmacology*
  • Oncogene Protein v-akt / metabolism
  • Random Allocation
  • Statistics as Topic
  • Taxoids / administration & dosage
  • Taxoids / adverse effects
  • Taxoids / blood
  • Taxoids / pharmacokinetics
  • Taxoids / therapeutic use*
  • Time Factors
  • Tumor Burden / drug effects
  • Xenograft Model Antitumor Assays

Substances

  • Antineoplastic Agents
  • Oligonucleotides, Antisense
  • Taxoids
  • Docetaxel
  • ErbB Receptors
  • Oncogene Protein v-akt