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PI3K(p110alpha) inhibitors as anti-cancer agents: minding the heart

Julie R McMullen1, Patrick Y Jay

  • 1Experimental Cardiology and Heart Failure Division, Baker Heart Research Institute, Melbourne, Victoria, Australia. Julie.mcmullen@baker.edu.au

Cell Cycle (Georgetown, Tex.)
|April 4, 2007
PubMed

Insights

Targeting phosphatidylinositol 3-kinase (PI3K) in cancer may harm the heart. PI3K inhibition accelerated heart failure in mice, suggesting risks for cancer patients with cardiovascular issues.

Area of Science:

  • Oncology
  • Cardiology
  • Molecular Biology

Background:

  • Phosphatidylinositol 3-kinase (PI3K) signaling, particularly the p110alpha isoform, is crucial for cancer cell growth and survival.
  • The PI3K pathway has diverse roles in various cell types, presenting challenges for targeted therapies.
  • Recent studies highlight the PI3K pathway's protective role in cardiac function.

Purpose of the Study:

  • To investigate the cardiac consequences of inhibiting PI3K(p110alpha) activity.
  • To understand the link between PI3K inhibition and cardiomyopathy observed in cancer patients.
  • To explore potential therapeutic strategies for cancer treatment with reduced cardiac risk.

Main Methods:

  • Utilized genetically modified mice with deficient PI3K(p110alpha) activity specifically in the heart.
  • Assessed cardiac function and response to pathological insults, including dilated and hypertrophic cardiomyopathy.
  • Compared the effects of PI3K(p110alpha) inhibition with a downstream effector inhibitor, targeting the mammalian target of rapamycin (mTOR).

Main Results:

  • Mice lacking PI3K(p110alpha) activity in the heart showed accelerated heart failure when subjected to cardiomyopathy.
  • These findings provide a mechanistic explanation for cardiac dysfunction in cancer patients treated with tyrosine kinase inhibitors.
  • In contrast, inhibiting mTOR, a downstream PI3K pathway component, did not result in adverse cardiac effects.

Conclusions:

  • PI3K(p110alpha) signaling is essential for protecting the heart against pathological stress.
  • Targeting PI3K(p110alpha) in cancer therapy may pose significant risks for patients with pre-existing cardiovascular conditions.
  • Further research into the complex PI3K pathway interactions is needed to develop safer anti-cancer drugs with minimal cardiac toxicity.

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