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Therapeutic implications of intrinsic or induced angiogenic growth factor redundancy in tumors revealed

Robert S Kerbel1

  • 1Sunnybrook & Women's College Health Sciences Centre and Department of Medical Biophysics, University of Toronto, Canada. robert.kerbel@swri.ca

Cancer Cell
|October 18, 2005
PubMed

Insights

Tumors can develop resistance to anti-angiogenic drugs by activating alternative blood vessel growth pathways, especially when tumor hypoxia increases. This study provides preclinical evidence for this evasion mechanism, impacting cancer treatment strategies.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cancer Research

Background:

  • Tumors utilize numerous pro-angiogenic growth factors, often amplified by hypoxia.
  • Redundancy in angiogenic pathways is a suspected cause of acquired resistance to targeted anti-angiogenic drugs.
  • Tumor hypoxia can increase in response to anti-angiogenic therapy.

Purpose of the Study:

  • To provide preclinical evidence for tumor cell evasion of anti-angiogenic drugs via alternate angiogenesis pathways.
  • To investigate the role of tumor hypoxia in mediating this drug resistance.
  • To explore implications for anti-angiogenic drug therapy and combination strategies.

Main Methods:

  • Preclinical tumor models were used to investigate mechanisms of acquired resistance.
  • Analysis focused on the activation of alternate angiogenesis pathways.
  • The impact of tumor hypoxia on drug resistance was assessed.

Main Results:

  • Definitive preclinical evidence demonstrates tumor cells evade anti-angiogenic drugs.
  • Alternate pathways of angiogenesis are activated, likely induced by increased tumor hypoxia.
  • This evasion mechanism has significant implications for treatment efficacy.

Conclusions:

  • Anti-angiogenic drug resistance can occur through activation of alternative angiogenesis pathways.
  • Increased tumor hypoxia plays a crucial role in mediating this resistance.
  • Findings impact strategies for prolonging anti-angiogenic drug effectiveness and combination therapies.

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