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Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis
Published on: February 16, 2015
Increased cell surface protease activity in UV-irradiated cells undergoing apoptosis
T J Piva1, C M Davern, C M Winterford
1Cancer Unit, Queensland Institute of Medical Research, Brisbane, Australia. t.piva@cqu.edu.au
Redox Report : Communications in Free Radical Research
|August 12, 2000
Summary
UVB radiation increases cell surface protease (CSP) activity during apoptosis. However, inhibiting caspase 3 did not affect CSP activation, suggesting this process is independent of caspase 3 in apoptotic cells.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- UVB irradiation induces apoptosis in HeLa cells.
- Apoptotic cells exhibit elevated cell surface protease (CSP) activity.
- Caspase 3 is a key enzyme in apoptosis signaling pathways.
Purpose of the Study:
- To investigate the role of caspase 3 in the activation of CSP during UVB-induced apoptosis.
- To determine if caspase 3 directly influences CSP activity in apoptotic cells.
Main Methods:
- HeLa cell cultures were exposed to UVB radiation.
- Cells were pre-treated with the caspase inhibitor DEVD.
- Caspase 3 activity and CSP activity were measured in treated and untreated cells.
Main Results:
- UVB-irradiated cells showed increased CSP activity compared to viable or necrotic cells.
- DEVD significantly inhibited caspase 3 activity in apoptotic cells.
- CSP activation remained unaffected by DEVD treatment in apoptotic cells.
Conclusions:
- Caspase 3 activity is not required for the activation of CSP in UVB-induced apoptotic cells.
- The findings indicate that CSP activation during apoptosis is independent of caspase 3.
- Further research is needed to identify the specific pathways regulating CSP activation in apoptosis.
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