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Updated: Aug 8, 2026
08:35
Examining BCL-2 Family Function with Large Unilamellar Vesicles
Published on: October 5, 2012
Involvement of hTERT in apoptosis induced by interference with Bcl-2 expression and function
D Del Bufalo1, A Rizzo, D Trisciuoglio
1Experimental Chemotherapy Laboratory, Experimental Research Center, Regina Elena Cancer Institute, Rome 00158, Italy.
Cell Death and Differentiation
|May 28, 2005
Summary
Telomerase (hTERT) plays a crucial role in Bcl-2-dependent apoptosis, inhibiting it independently of its catalytic activity. Overexpression of hTERT prevents mitochondrial dysfunction and apoptosis triggered by Bcl-2 inhibition.
Area of Science:
- Molecular Biology
- Cell Biology
- Cancer Research
Background:
- Bcl-2 family proteins are critical regulators of apoptosis (programmed cell death).
- Telomerase, particularly its catalytic subunit human telomerase reverse transcriptase (hTERT), is often upregulated in cancer.
- The precise role of telomerase in Bcl-2-dependent apoptosis remains incompletely understood.
Purpose of the Study:
- To investigate the involvement of telomerase (hTERT) in Bcl-2-dependent apoptosis.
- To elucidate the mechanisms by which hTERT influences apoptosis induced by Bcl-2 inhibition.
Main Methods:
- Utilized a Bcl-2/Bcl-xL bispecific antisense oligonucleotide (4625) and a Bcl-2 inhibitor (HA14-1).
- Assessed protein expression, telomerase activity, and subcellular localization of hTERT.
- Employed RNA interference for hTERT downregulation and overexpression of wild-type and mutant hTERT.
- Evaluated mitochondrial dysfunction and apoptosis induction.
Main Results:
- Apoptosis induced by 4625 correlated with decreased Bcl-2 and telomerase activity.
- HA14-1 induced apoptosis without altering Bcl-2 or telomerase levels but caused hTERT relocalization to the cytoplasm.
- hTERT downregulation enhanced apoptosis, while hTERT overexpression (including inactive mutants) blocked apoptosis, mitochondrial dysfunction, and nuclear translocation of hTERT.
Conclusions:
- hTERT plays a significant role in regulating mitochondrial apoptosis.
- hTERT inhibits apoptosis induced by targeted Bcl-2 inhibition, irrespective of its telomere-lengthening activity.
- These findings highlight a novel non-canonical function of hTERT in apoptosis regulation.
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