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Updated: Jun 1, 2026
11:44
Analysis of Combinatorial miRNA Treatments to Regulate Cell Cycle and Angiogenesis
Published on: March 30, 2019
MiRNA-27a controls FBW7/hCDC4-dependent cyclin E degradation and cell cycle progression
Mikael Lerner1, Josefin Lundgren, Shahab Akhoondi
1Department of Oncology-Pathology; Cancer Center Karolinska (CCK), Karolinska Institutet, Stockholm, Sweden.
Cell Cycle (Georgetown, Tex.)
|May 21, 2011
Summary
MicroRNA-27a suppresses the tumor suppressor FBW7, impacting cell cycle progression and cyclin E degradation. This microRNA regulation is implicated in pediatric B-ALL cancer.
Area of Science:
- Molecular Biology
- Cancer Research
- Cell Cycle Regulation
Background:
- FBW7 (F-box protein 7) is a crucial tumor suppressor.
- It functions in an SCF ubiquitin ligase complex, degrading oncoproteins.
- Regulation of FBW7 by microRNAs is largely unexplored.
Purpose of the Study:
- To investigate microRNA regulation of FBW7.
- To identify specific microRNAs targeting FBW7.
- To understand the functional consequences of FBW7 microRNA regulation in cell cycle and cancer.
Main Methods:
- Bioinformatic analysis and microRNA screening.
- Luciferase reporter assays to validate microRNA targets.
- Western blotting for protein levels and ubiquitylation assays.
- Cell cycle analysis and DNA replication stress assays.
- Analysis of microRNA and FBW7 expression in pediatric B-ALL patient samples.
Main Results:
- MicroRNA-27a (miR-27a) was identified as a key suppressor of FBW7.
- miR-27a inhibits FBW7-mediated ubiquitylation and degradation of cyclin E.
- miR-27a's suppression of FBW7 is cell-cycle-dependent, with relief at the G1/S transition.
- Overexpression of miR-27a leads to cell cycle defects and DNA replication stress.
- miR-27a is overexpressed in pediatric B-ALL, inversely correlating with FBW7 in hyperdiploid cases.
Conclusions:
- MicroRNA-27a plays a significant role in regulating FBW7 activity.
- This regulation fine-tunes cell cycle progression, particularly cyclin E turnover.
- Dysregulation of the miR-27a/FBW7 axis contributes to pediatric B-ALL pathogenesis.
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