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Updated: May 11, 2026
08:47
Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
p14ARF induces apoptosis via an entirely caspase-3-dependent mitochondrial amplification loop
Ana Milojkovic1, Philipp G Hemmati, Annika Müer
1Clinical and Molecular Oncology, Max Delbrück Centrum für Molekulare Medizin, Berlin-Buch, Germany.
International Journal of Cancer
|May 21, 2013
Summary
The tumor suppressor p14(ARF) induces cell death in breast cancer cells by inhibiting cell cycle arrest, promoting apoptosis via a caspase-3 dependent pathway. This finding highlights a novel therapeutic strategy for overcoming resistance to cancer cell death.
Area of Science:
- Oncology
- Molecular Biology
- Cell Biology
Background:
- The p14(ARF) tumor suppressor is known to induce apoptosis or cell cycle arrest in response to oncogenic stress.
- MCF-7 breast carcinoma cells expressing p14(ARF) typically exhibit G1 and G2 cell cycle arrest rather than apoptosis.
Purpose of the Study:
- To investigate the role of cell cycle arrest in p14(ARF) -induced cell death.
- To determine the involvement of caspase-3 in p14(ARF) -mediated apoptosis in MCF-7 cells.
Main Methods:
- Expression of p14(ARF) in MCF-7 cells with varying caspase-3 proficiency.
- Inhibition of cell cycle arrest.
- Assessment of apoptosis induction, cell cycle progression, and mitochondrial pathway activation (membrane potential, cytochrome c release).
Main Results:
- Inhibition of cell cycle arrest in caspase-3 proficient MCF-7 cells led to p14(ARF) -induced apoptosis, independent of S-phase or mitotic entry.
- Caspase-3 deficient MCF-7 cells were resistant to p14(ARF) -induced apoptosis.
- Apoptosis involved mitochondrial membrane potential dissipation and cytochrome c release, dependent on caspase-3.
- Caspase-3 may act upstream of mitochondria or amplify the apoptotic signal.
Conclusions:
- Cell cycle checkpoint abrogation overcomes resistance to p14(ARF) -induced cell death.
- Caspase-3 is essential for p14(ARF) -induced apoptosis in MCF-7 cells, potentially acting in a non-canonical pathway or amplifying mitochondrial signaling.
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