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Apoptotic proteins with non-apoptotic activity: expression and function in cancer
Varda Shoshan-Barmatz1,2, Tasleem Arif3, Anna Shteinfer-Kuzmine4
1Department of Life Sciences, Ben-Gurion University of the Negev, 84105, Beer Sheva, Israel. vardasb@bgu.ac.il.
Summary
Apoptosis proteins have dual roles, participating in programmed cell death and other physiological functions like cell cycle regulation. Some apoptotic proteins, like VDAC1 and SMAC/Diablo, are overexpressed in cancers, exhibiting non-cell death activities.
Area of Science:
- Cell Biology
- Molecular Biology
- Cancer Biology
Background:
- Apoptosis, or programmed cell death, is crucial for tissue homeostasis.
- Two main pathways initiate apoptosis: extrinsic (death receptors) and intrinsic (mitochondrial).
- Apoptotic proteins are increasingly recognized for non-cell death functions.
Purpose of the Study:
- To review the unconventional, non-cell death roles of apoptotic proteins.
- To focus on mitochondrial proteins VDAC1 and SMAC/Diablo.
- To discuss their dual pro-apoptotic and non-apoptotic functions in cancer.
Main Methods:
- Literature review of apoptosis pathways and protein functions.
- Analysis of studies reporting non-conventional roles of apoptotic proteins.
- Focus on VDAC1 and SMAC/Diablo overexpression in cancer.
Main Results:
- Apoptotic proteins regulate cell cycle, differentiation, metabolism, and immunity.
- VDAC1 and SMAC/Diablo exhibit dual roles, promoting apoptosis and other functions.
- These proteins are overexpressed in cancers, presenting a paradox.
Conclusions:
- Apoptotic proteins possess significant non-cell death functions.
- The overexpression of VDAC1 and SMAC/Diablo in cancer warrants further investigation.
- Understanding the switch between apoptotic and non-apoptotic activities is critical.
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