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Updated: Jun 2, 2026
11:39
Assessing Autophagic Flux by Measuring LC3, p62, and LAMP1 Co-localization Using Multispectral Imaging Flow Cytometry
Published on: July 21, 2017
Oncogene-induced autophagy and the Goldilocks principle
1Molecular Cell Biology Laboratory, The Smurfit Institute of Genetics, Trinity College, Dublin, Ireland. martinsj@tcd.ie
Autophagy
|May 10, 2011
Summary
Oncogenic H-Ras promotes cell death by upregulating autophagy via Beclin 1 and Noxa. This oncogene-induced cell death is reduced by inhibiting autophagy or increasing Bcl-2 family proteins.
Area of Science:
- Cell Biology
- Molecular Oncology
Background:
- Oncogenes can influence cellular autophagy, but the precise mechanisms and outcomes are not fully understood.
- Autophagy plays a complex role in cancer, potentially acting as a tumor suppressor or promoter depending on context.
Purpose of the Study:
- To elucidate the molecular mechanisms by which oncogenic H-Ras (V12) induces autophagy.
- To investigate the role of autophagy in oncogene-induced cell death and its regulation by Bcl-2 family proteins.
Main Methods:
- Utilized cell culture models expressing oncogenic H-Ras (V12).
- Assessed autophagic flux, Beclin 1, Noxa, Mcl-1, and Bcl-xL expression levels.
- Employed gene knockdown (BECLIN 1, ATG5, ATG7) and overexpression (Mcl-1, Bcl-2, Bcl-xL) strategies.
Main Results:
- Oncogenic H-Ras (V12) expression upregulates Beclin 1 and Noxa, promoting autophagic flux.
- Noxa mediates H-Ras-induced autophagic cell death by displacing Mcl-1 and Bcl-xL from Beclin 1.
- Inhibition of autophagy or increased expression of Mcl-1, Bcl-2, or Bcl-xL attenuates H-Ras-induced cell death.
Conclusions:
- High-intensity oncogene activation can trigger excessive autophagy, leading to cell death.
- Cells may evolve mechanisms to reduce autophagy capacity, such as Beclin 1 loss or Bcl-2 family protein upregulation, to counteract oncogene-induced death.
- Autophagy regulation is a critical factor in the cellular response to oncogenic stress.
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