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Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
PIDDosome-independent tumor suppression by Caspase-2
C Manzl1, L Peintner, G Krumschnabel
1Division of Developmental Immunology, BIOCENTER, Medical University Innsbruck, Austria.
Cell Death and Differentiation
|May 19, 2012
Summary
The PIDDosome complex, involving PIDD and Caspase-2, plays a role in tumor suppression. Gene ablation of Pidd or Caspase-2 failed to prevent lymphoma and fibrosarcoma development, but Caspase-2 suppressed c-Myc-driven tumors.
Area of Science:
- Molecular Biology
- Cellular Biology
- Oncology
Background:
- The PIDDosome is a protein complex that activates Caspase-2, a protease involved in apoptosis.
- PIDD participates in p53-mediated cell death, DNA repair, and NF-κB activation, processes crucial for tumor suppression.
- Dysregulation of PIDDosome components is observed in human cancers.
Purpose of the Study:
- To investigate the role of PIDDosome components (PIDD and Caspase-2) in oncogenesis induced by DNA damage or oncogenic stress.
- To analyze the tumor suppressive functions of PIDD and Caspase-2 in gene-ablated mouse models.
Main Methods:
- Gene ablation of Pidd or Caspase-2 in mice.
- Induction of oncogenesis via gamma-irradiation, 3-methylcholanthrene, or aberrant c-Myc expression.
- Assessment of tumor formation, p53 status, and tumor cell dissemination.
Main Results:
- Pidd or Caspase-2 deficiency did not prevent lymphoma or fibrosarcoma development following DNA damage.
- Caspase-2 exhibited tumor suppressive activity against c-Myc-induced tumors, independent of PIDD, Bid, or Trail.
- Pidd deficiency led to abnormal M-phase progression and delayed disease onset in c-Myc-driven tumors.
Conclusions:
- PIDD and Caspase-2 play distinct roles in tumor suppression under different oncogenic stresses.
- Caspase-2's tumor suppressive function in c-Myc-driven oncogenesis is linked to reduced p53 loss and altered tumor cell spread.
- PIDD influences M-phase progression and disease onset, suggesting differential engagement in oncogenesis.
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