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Updated: May 19, 2026

Vasodilation of Isolated Vessels and the Isolation of the Extracellular Matrix of Tight-skin Mice
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Published on: March 24, 2017

The decline and fall of the IGF-I receptor

Renato Baserga1

  • 1Department of Cancer Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.

Journal of Cellular Physiology
|August 29, 2012
PubMed

Insights

Targeting the insulin-like growth factor 1 receptor (IGF-IR) in human cancers has yielded disappointing results. This review discusses reasons for failure and explores IGF-IR's potential as a secondary cancer target.

Area of Science:

  • Oncology
  • Molecular Biology
  • Drug Development

Background:

  • The insulin-like growth factor 1 receptor (IGF-IR) pathway is implicated in various human cancers.
  • Targeting IGF-IR has been investigated as a therapeutic strategy for cancer treatment.

Purpose of the Study:

  • To review the clinical efficacy of targeting IGF-IR in human cancers.
  • To analyze the reasons behind the limited success of IGF-IR-targeted therapies.
  • To explore alternative roles for IGF-IR in cancer treatment.

Main Methods:

  • Systematic literature review of preclinical and clinical studies.
  • Analysis of clinical trial data for IGF-IR inhibitors.
  • Discussion of biological mechanisms underlying IGF-IR function in cancer.

Main Results:

  • Clinical trials targeting IGF-IR as a primary agent have shown disappointing outcomes.
  • Several factors contribute to the failure, including pathway redundancy and tumor heterogeneity.
  • Limited efficacy observed in monotherapy settings.

Conclusions:

  • Directly targeting IGF-IR as a sole therapeutic strategy in cancer has largely failed.
  • Further investigation is warranted to explore IGF-IR's role as a secondary target in combination therapies.
  • Understanding resistance mechanisms is crucial for future therapeutic development.

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