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Mechanism of Regulation of Adipocyte Numbers in Adult Organisms Through Differentiation and Apoptosis Homeostasis
Published on: June 3, 2016
Foxa2 may modulate hepatic apoptosis through the cIAP1 pathway
Kewei Wang1, John J Brems, Richard L Gamelli
1Departments of Surgery, University of Illinois College of Medicine at Peoria, IL 61605, USA. kewang@uic.edu
Cellular Signalling
|January 1, 2013
Summary
The liver transcription factor Foxa2 (forkhead box A2) protects against liver injury by inhibiting hepatocyte apoptosis. Foxa2 regulates the anti-apoptotic gene cIAP1, offering a therapeutic target for liver diseases.
Area of Science:
- Hepatology
- Molecular Biology
- Cell Death Research
Background:
- Hepatocyte apoptosis is a key feature of chronic liver injury.
- The precise molecular mechanisms driving this apoptosis are not fully understood.
- The liver-enriched transcription factor Foxa2 (forkhead box A2) is linked to inflammation and neoplasia and may regulate apoptosis.
Purpose of the Study:
- To investigate the relationship between Foxa2 and hepatic apoptosis.
- To elucidate the molecular mechanisms by which Foxa2 influences liver cell death.
Main Methods:
- Induction of apoptosis in liver cells using various factors.
- Measurement of caspase activity and TUNEL assay to quantify apoptosis.
- Analysis of Foxa2 expression, gene silencing (siRNA), and overexpression (vectors) in HepG2 cells.
- Correlation of Foxa2 levels with anti-apoptotic gene expression (cIAP1, cIAP2, XIAP, survivin).
- Electrophoretic mobility shift assay (EMSA), gel supershift assay, and chromatin immunoprecipitation (ChIP) assay to assess Foxa2 binding to the cIAP1 promoter.
Main Results:
- Apoptotic liver injury correlated with decreased Foxa2 expression.
- Foxa2 overexpression reduced apoptosis, while Foxa2 silencing increased apoptosis in HepG2 cells.
- Foxa2 expression levels were associated with anti-apoptotic genes, notably cIAP1.
- Foxa2 directly binds to the cIAP1 promoter, regulating its activity and expression.
Conclusions:
- Foxa2 transcription factor modulates hepatic apoptosis potentially via the cIAP1 signaling pathway.
- Foxa2 represents a potential therapeutic target for treating liver diseases characterized by apoptosis.
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