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Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry
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Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry

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Biological characterization of ETP-46321 a selective and efficacious inhibitor of phosphoinositide-3-kinases

Teresa G Granda1, David Cebrián, Sonia Martínez

  • 1Health Research Institut Biocruces, Cruces Hospital, Plaza Cruces s/n, Baracaldo 48903, Spain.

Investigational New Drugs
|May 25, 2012
PubMed

Insights

A novel compound, ETP-46321, potently inhibits phosphoinositide-3-kinase alpha (PI3Kα) signaling, showing anti-cancer effects. This PI3K inhibitor demonstrates therapeutic potential by halting tumor growth and synergizing with existing cancer treatments.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Phosphoinositide-3-kinase (PI3K) signaling is frequently dysregulated in various cancers, making it a key therapeutic target.
  • Developing selective PI3K inhibitors is crucial for effective cancer treatment with minimized off-target effects.

Purpose of the Study:

  • To identify and characterize a novel imidazopyrazine derivative, ETP-46321, as a potent PI3K inhibitor.
  • To evaluate the anti-cancer efficacy and synergistic potential of ETP-46321 in preclinical models.

Main Methods:

  • In vitro kinase assays were performed to determine the inhibitory potency of ETP-46321 against PI3K isoforms and related kinases.
  • Cell-based assays assessed the compound's effects on PI3K signaling, cell cycle, and angiogenesis.
  • In vivo xenograft models were used to evaluate ETP-46321's anti-tumor activity and its synergy with other therapeutics.

Main Results:

  • ETP-46321 demonstrated potent and selective inhibition of PI3Kα (IC50 < 5 μM), with significantly lower potency against PI3Kδ, β, and γ.
  • The compound effectively inhibited PI3K signaling, induced cell cycle arrest, and reduced VEGF-dependent sprouting in vitro.
  • In vivo studies showed ETP-46321 reduced Akt phosphorylation, delayed tumor growth in colon and lung cancer xenografts, and synergized with Doxotaxel in ovarian cancer models.

Conclusions:

  • ETP-46321 is a highly selective PI3Kα inhibitor with demonstrated anti-proliferative and anti-angiogenic properties.
  • The compound exhibits significant anti-tumor efficacy in vivo and synergizes with conventional chemotherapeutics, highlighting its therapeutic potential in oncology.

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