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07:02
In Vivo Inhibition of MicroRNA to Decrease Tumor Growth in Mice
Published on: August 23, 2019
p16(INK4a) translation suppressed by miR-24
Ashish Lal1, Hyeon Ho Kim, Kotb Abdelmohsen
1Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, Maryland, United States of America. alal@cbrinstitute.org
Plos One
|March 28, 2008
Summary
MicroRNA 24 (miR-24) suppresses the tumor suppressor p16INK4a in aging cells. Decreased miR-24 levels during senescence correlate with increased p16, suggesting miR-24 regulates p16 translation.
Area of Science:
- Molecular Biology
- Cellular Senescence
- Gene Regulation
Background:
- The tumor suppressor p16INK4a is upregulated during cellular aging and senescence.
- Understanding the regulatory mechanisms of p16INK4a is crucial for aging research.
Purpose of the Study:
- To investigate the role of microRNA 24 (miR-24) in regulating p16INK4a expression.
- To elucidate the mechanism by which miR-24 affects p16INK4a levels.
Main Methods:
- Utilized human diploid fibroblasts and cervical carcinoma cells.
- Manipulated miR-24 levels through overexpression and antisense inhibition.
- Assessed p16INK4a protein and mRNA levels.
- Employed EGFP-p16 reporter assays to study translation.
Main Results:
- miR-24 was found to suppress p16INK4a expression in tested cell lines.
- Replicative senescence was associated with reduced miR-24 levels and increased p16INK4a.
- Overexpression of miR-24 decreased p16INK4a protein but not mRNA.
- Inhibition of miR-24 enhanced p16INK4a protein levels and translation.
Conclusions:
- miR-24 acts as a repressor of p16INK4a translation.
- The findings suggest miR-24 regulates both initiation and elongation phases of p16INK4a translation.
- miR-24 is a key regulator in the context of cellular senescence and aging.
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