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Updated: Aug 8, 2026
09:24
3-D Cell Culture System for Studying Invasion and Evaluating Therapeutics in Bladder Cancer
Published on: September 13, 2018
Membrane potassium channels and human bladder tumor cells: II. Growth properties
R Wondergem1, M Cregan, L Strickler
1Department of Physiology, James H. Quillen College of Medicine, East Tennessee State University, Johnson City 37614-0576, USA.
The Journal of Membrane Biology
|March 11, 1998
Summary
Glibenclamide inhibits human bladder cancer cell growth by affecting cell cycle progression. Diazoxide, however, stimulates growth without increasing cell numbers, indicating KATP channels
Area of Science:
- Cell Biology
- Pharmacology
- Oncology
Background:
- Human bladder carcinoma (HTB-9) cell growth regulation is not fully understood.
- Membrane KATP channels are implicated in various cellular processes.
- The role of KATP channels in bladder cancer progression requires further investigation.
Purpose of the Study:
- To investigate the effects of glibenclamide and diazoxide on HTB-9 cell growth in vitro.
- To determine the involvement of membrane KATP channels in bladder cancer cell proliferation.
Main Methods:
- Cell growth was assessed using cell counts, protein accumulation, and 3H-thymidine uptake.
- Dose-inhibition curves were established for glibenclamide.
- Cell cycle distribution was analyzed by flow cytometry using bromodeoxyuridine.
Main Results:
- Glibenclamide significantly reduced HTB-9 cell proliferation at concentrations as low as 1 microM (IC50 = 73 microM).
- Glibenclamide treatment altered cell cycle distribution, increasing G0/G1 phase and decreasing S phase.
- Diazoxide stimulated protein accumulation but did not increase cell number in HTB-9 cells.
Conclusions:
- The sulfonylurea receptor and membrane KATP channels are involved in regulating HTB-9 cell growth.
- KATP channels are not the rate-limiting factor in the signaling pathways controlling the cell cycle in these cells.
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