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Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
Role for p53 in selenium-induced senescence
Min Wu1, Ryan T Y Wu, Thomas T Y Wang
1Department of Nutrition and Food Science, University of Maryland, College Park, Maryland 20742, United States.
Journal of Agricultural and Food Chemistry
|October 7, 2011
Summary
The tumor suppressor p53 is crucial for selenium-induced cell senescence in normal fibroblasts. Depleting p53 disrupts cell cycle arrest and increases genome instability, highlighting its critical role in this process.
Area of Science:
- Cellular senescence
- DNA damage response
- Cancer prevention
Background:
- Tumor suppressor p53 and ATM kinase are key in senescence.
- Selenium compounds activate ATM-dependent senescence in fibroblasts.
- The role of p53 in selenium-induced senescence requires further investigation.
Purpose of the Study:
- To investigate the role of p53 in selenium-induced senescence.
- To determine if p53 is essential for the senescence response to methylseleninic acid (MSeA).
Main Methods:
- shRNA knockdown to deplete p53 in MRC-5 cells.
- Methylseleninic acid (MSeA) treatment to induce senescence.
- Assays for senescence markers (β-galactosidase), cell cycle arrest, and genome instability.
- Inhibition of ATM and DNA-PK kinases.
Main Results:
- p53 depletion reduced senescence markers and disrupted cell cycle arrest (S and G2/M phases).
- p53-depleted cells showed increased sensitivity to MSeA and heightened genome instability.
- ATM and DNA-PK inhibitors reduced MSeA cytotoxicity in control cells but not in p53-depleted cells.
Conclusions:
- p53 is essential for inducing senescence in response to selenium compounds in MRC-5 cells.
- The p53 pathway is critical for mediating the anti-cancer effects of selenium.
- These findings underscore the importance of p53 in cellular defense mechanisms against genotoxic stress.
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