Disruption of the protein interaction between FAK and IGF-1R inhibits melanoma tumor growth

Cell Cycle. 2012 Sep 1;11(17):3250-9. doi: 10.4161/cc.21611. Epub 2012 Aug 16.

Abstract

FAK (focal adhesion kinase) and IGF-1R (insulin-like growth factor receptor-1) directly interact with each other and thereby activate crucial signaling pathways that benefit cancer cells. Inhibition of FAK and IGF-1R function has been shown to significantly decrease cancer cell proliferation and increase sensitivity to chemotherapy and radiation treatment. As a novel approach in human melanoma, we evaluated the effect of a small-molecule compound that disrupts the protein interaction of FAK and IGF-1R. Previously, using virtual screening and functional testing, we identified a lead compound (INT2-31) that targets the known FAK-IGF-1R protein interaction site. We studied the ability of this compound to disrupt FAK-IGF-1R protein interactions, inhibit downstream signaling, decrease human melanoma cell proliferation, alter cell cycle progression, induce apoptosis and decrease tumor growth in vivo. INT2-31 blocked the interaction of FAK and IGF-1R in vitro and in vivo in melanoma cells and tumor xenografts through precluding the activation of IRS-1, leading to reduced phosphorylation of AKT upon IGF-1 stimulation. As a result, INT2-31 significantly inhibited cell proliferation and viability (range 0.05-10 μM). More importantly, 15 mg/kg of INT2-31 given for 21 d via intraperitoneal injection disrupted the interaction of FAK and IGF-1R and effectively decreased phosphorylation of tumor AKT, resulting in significant melanoma tumor regression in vivo. Our data suggest that the FAK-IGF-1R protein interaction is an important target, and disruption of this interaction with a novel small molecule (INT2-31) has potential anti-neoplastic therapeutic effects in human melanoma.

Publication types

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

MeSH terms

  • Apoptosis / drug effects
  • Blotting, Western
  • Cell Line
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Flow Cytometry
  • Focal Adhesion Kinase 1 / metabolism*
  • Humans
  • Immunohistochemistry
  • Immunoprecipitation
  • In Situ Nick-End Labeling
  • Melanoma / drug therapy
  • Melanoma / metabolism
  • Melanoma / physiopathology*
  • Protein Kinase Inhibitors / pharmacology*
  • Protein Kinase Inhibitors / therapeutic use
  • Purine Nucleosides / pharmacology*
  • Purine Nucleosides / therapeutic use
  • RNA, Small Interfering / genetics
  • Receptor, IGF Type 1 / metabolism*
  • Signal Transduction / drug effects*
  • Signal Transduction / physiology

Substances

  • 4-(methylthio)-7-(5-O-phosphonoribofuranosyl)-7H-pyrrolo(2,3-d)pyrimidine
  • Protein Kinase Inhibitors
  • Purine Nucleosides
  • RNA, Small Interfering
  • Receptor, IGF Type 1
  • Focal Adhesion Kinase 1
  • PTK2 protein, human