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PPARα and PPARγ regulate the nucleoside transporter hENT1
Trinidad D Montero1, Dusan Racordon, Loreto Bravo
1Department of Hematology-Oncology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
Biochemical and Biophysical Research Communications
|February 22, 2012
Summary
Peroxisome proliferator-activated receptors (PPARs) influence human equilibrative nucleoside transporter 1 (hENT1) expression and activity. PPARα activation, but not PPARγ, enhances hENT1-mediated nucleoside transport via a PPRE-dependent mechanism.
Area of Science:
- Molecular biology
- Pharmacology
- Cancer research
Background:
- Human equilibrative nucleoside transporter 1 (hENT1) is crucial for nucleoside analog chemotherapy efficacy.
- Peroxisome proliferator-activated receptors (PPARs) are implicated in regulating hENT1.
- Understanding this regulation is key to optimizing cancer treatment.
Purpose of the Study:
- To investigate the role of PPARs (specifically PPARα and PPARγ) in modulating hENT1 expression and activity.
- To determine if PPAR-mediated regulation of hENT1 is dependent on Peroxisome proliferator response elements (PPREs).
Main Methods:
- Utilized A2780 cancer cells to study PPARs' effects on hENT1.
- Administered PPARα and PPARγ agonists (Wy14,643 and RGZ).
- Performed promoter analysis, including luciferase reporter assays with hENT1 promoter constructs containing putative PPREs.
Main Results:
- Both PPARα and PPARγ agonists increased hENT1 expression.
- Only PPARα activation or overexpression led to enhanced hENT1 transport activity.
- Promoter analysis indicated that PPARα-mediated hENT1 regulation is PPRE-dependent, while PPARγ's is not.
Conclusions:
- PPARα and PPARγ activation differentially modulate hENT1 expression and activity.
- PPARα significantly enhances hENT1 function through a PPRE-dependent mechanism.
- These findings highlight PPARs as potential targets for improving nucleoside analog chemotherapy.
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