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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Overcoming hypoxia-induced apoptotic resistance through combinatorial inhibition of GSK-3β and CDK1

Patrick A Mayes1, Nathan G Dolloff, Colin J Daniel

  • 1Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.

Cancer Research
|June 8, 2011
PubMed

Insights

This study identified small molecules that inhibit GSK-3β and CDK1, reversing cancer cell resistance to apoptosis under hypoxia. This approach enhances chemotherapy efficacy by blocking tumor growth and angiogenesis.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Tumor hypoxia is a major obstacle in cancer treatment, leading to resistance to apoptosis.
  • Identifying therapeutic strategies to overcome hypoxia-induced resistance is crucial for improving cancer therapy outcomes.

Purpose of the Study:

  • To identify small molecules capable of reversing apoptotic resistance in hypoxic cancer cells.
  • To investigate the therapeutic potential of inhibiting glycogen synthase kinase 3 beta (GSK-3β) and cyclin-dependent kinase 1 (CDK1) in hypoxic tumors.

Main Methods:

  • Conducted a cell-based screen to identify small molecules targeting hypoxic cancer cells.
  • Investigated the effects of inhibiting GSK-3β and CDK1 on apoptotic sensitivity, c-Myc, c-IAP2, and hypoxia-inducible factor 1-alpha (HIF-1α) levels.
  • Evaluated the efficacy of identified compounds in preclinical mouse models, assessing tumor cell death, angiogenesis, and tumor growth.

Main Results:

  • Identified a class of small molecules that inhibit GSK-3β and CDK1, sensitizing hypoxic cancer cells to apoptosis.
  • Combinatorial inhibition led to increased c-Myc and decreased c-IAP2 and HIF-1α expression in hypoxic cells and tumors.
  • In vivo studies demonstrated augmented tumor cell death, inhibited angiogenesis, and reduced tumor growth when combined with chemotherapy.

Conclusions:

  • Combinatorial inhibition of GSK-3β and CDK1 effectively sensitizes hypoxic tumors to apoptosis.
  • This strategy offers a promising preclinical validation for a novel and translatable approach to enhance cancer therapy.

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