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NHERF1/EBP50 as a Target for Modulation of MRP Function in HepG2 Cells
Atsushi Kawase1, Miho Hirosoko1, Yuka Sugihara1
1Department of Pharmacy, Faculty of Pharmacy, Kindai University, Osaka 577-8502, Japan.
Pharmaceuticals (Basel, Switzerland)
|April 3, 2021
Summary
This study shows that EBP50 knockdown in liver cancer cells reduces the activity of key drug efflux transporters, P-gp and MRP. A TAT-PDZ1 peptide was also found to modulate these transporter activities.
Area of Science:
- Biochemistry
- Molecular Biology
- Cancer Research
Background:
- Increased expression of efflux transporters (ETs) is a major cause of drug resistance in cancer.
- Scaffold proteins like ezrin/radixin/moesin (ERM) and NHERF1/EBP50 are involved in regulating cellular processes, including transporter activity.
Purpose of the Study:
- To investigate whether EBP50 modulates ET activities in human liver cancer HepG2 cells.
- To explore the potential of targeting EBP50-ET interactions for overcoming drug resistance.
Main Methods:
- Utilized EBP50 siRNA for gene knockdown in HepG2 cells.
- Employed a designed TAT-PDZ1 peptide to interfere with EBP50-ET interactions.
- Measured intracellular accumulation of specific ET substrates: Rho123 (P-gp), CDF (MRP), and H33342 (BCRP).
Main Results:
- EBP50 knockdown led to significantly higher intracellular accumulation of Rho123 and CDF, indicating decreased P-gp and MRP activity.
- BCRP activity was not affected by EBP50 knockdown.
- TAT-PDZ1 peptide treatment significantly increased CDF accumulation, suggesting modulation of MRP activity.
Conclusions:
- EBP50 plays a role in modulating the activity of efflux transporters, specifically P-gp and MRP, in liver cancer cells.
- This study is the first to report the use of a competitive peptide to modulate EBP50-MRP interactions.
- Targeting EBP50 interactions presents a potential novel strategy for overcoming cancer multidrug resistance.
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