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Updated: Jun 17, 2026
15:53
Cell Death Associated with Abnormal Mitosis Observed by Confocal Imaging in Live Cancer Cells
Published on: August 21, 2013
An essential role for p73 in regulating mitotic cell death
W H Toh1, S Y Nam, K Sabapathy
1Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore.
Cell Death and Differentiation
|December 17, 2009
Summary
The tumor suppressor p73 protein regulates programmed cell death during mitosis, independent of p53. It induces the expression of Bim, a pro-apoptotic protein, to promote cell death during mitotic arrest.
Area of Science:
- Cell Biology
- Molecular Biology
- Cancer Research
Background:
- The molecular mechanisms governing cell death during mitosis are not fully understood.
- Mitotic cell death is a critical process that can be dysregulated in cancer.
Purpose of the Study:
- To investigate the role of p73 in regulating cell death during mitosis.
- To elucidate the molecular pathway through which p73 influences mitotic cell death.
Main Methods:
- Utilized various methods to induce mitotic arrest and cell death.
- Assessed the expression levels of p73 and Bim.
- Investigated the binding of p73 to the Bim gene.
- Evaluated the impact of p73 and Bim silencing on mitotic cell death.
Main Results:
- p73, but not p53, plays a crucial role in mitotic cell death.
- p73 induces the expression of the pro-apoptotic protein Bim by directly binding to its regulatory elements.
- Silencing of p73 or Bim abrogated or rescued mitotic cell death, respectively.
- The p73-mediated pathway is independent of spindle checkpoint proteins BubR1 and Mad2.
Conclusions:
- The p73-Bim axis is a key regulator of mitotic cell death.
- p73 promotes apoptosis during mitotic arrest by upregulating Bim expression.
- This pathway is distinct from p53-mediated apoptosis and spindle checkpoint regulation.
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