Regulation of epidermal growth factor receptor signaling and erlotinib sensitivity in head and neck cancer cells by miR-7

PLoS One. 2012;7(10):e47067. doi: 10.1371/journal.pone.0047067. Epub 2012 Oct 24.

Abstract

Elevated expression and activity of the epidermal growth factor receptor (EGFR)/protein kinase B (Akt) signaling pathway is associated with development, progression and treatment resistance of head and neck cancer (HNC). Several studies have demonstrated that microRNA-7 (miR-7) regulates EGFR expression and Akt activity in a range of cancer cell types via its specific interaction with the EGFR mRNA 3'-untranslated region (3'-UTR). In the present study, we found that miR-7 regulated EGFR expression and Akt activity in HNC cell lines, and that this was associated with reduced growth in vitro and in vivo of cells (HN5) that were sensitive to the EGFR tyrosine kinase inhibitor (TKI) erlotinib (Tarceva). miR-7 acted synergistically with erlotinib to inhibit growth of erlotinib-resistant FaDu cells, an effect associated with increased inhibition of Akt activity. Microarray analysis of HN5 and FaDu cell lines transfected with miR-7 identified a common set of downregulated miR-7 target genes, providing insight into the tumor suppressor function of miR-7. Furthermore, we identified several target miR-7 mRNAs with a putative role in the sensitization of FaDu cells to erlotinib. Together, these data support the coordinate regulation of Akt signaling by miR-7 in HNC cells and suggest the therapeutic potential of miR-7 alone or in combination with EGFR TKIs in this disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Cell Line, Tumor
  • ErbB Receptors / genetics
  • ErbB Receptors / metabolism*
  • Erlotinib Hydrochloride
  • Head and Neck Neoplasms / pathology*
  • Humans
  • MicroRNAs / physiology*
  • Oligonucleotide Array Sequence Analysis
  • Protein Kinase Inhibitors / pharmacology*
  • Proto-Oncogene Proteins c-akt / metabolism
  • Quinazolines / pharmacology*
  • RNA, Messenger / genetics
  • Signal Transduction*

Substances

  • 3' Untranslated Regions
  • MIRN7 microRNA, human
  • MicroRNAs
  • Protein Kinase Inhibitors
  • Quinazolines
  • RNA, Messenger
  • Erlotinib Hydrochloride
  • ErbB Receptors
  • Proto-Oncogene Proteins c-akt

Grants and funding

This work was supported by the National Health and Medical Research Council of Australia and the Medical Research Commercialization Fund of Australia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.