The potent inhibitory effects of cisapride, a specific blocker for human ether-a-go-go-related gene (HERG) channel, on gastric cancer cells

Background: Ion channels may play a role in carcinogenesis. Human ether-go-go-related gene (HERG) encoding one of the components of delayed rectifier potassium currents has been indicated with involvement in tumor cell growth and death.Our aim is to investigate the effects of cisapride, a specific blocker for HERG channel, on human gastric cancer cells. Methods: The effects of cisapride on the proliferation, clonogenicity, cell cycle andapoptosis of gastric cancer cells were evaluated by MTT assay, clonogenicity assay, flow cytometry and transmission electron microscopy. The expression of HERG mRNA and protein in gastric cancer cells and tissues was measured by RT-PCR, Western blot and immunohistochemistry, respectively. Results: HERG mRNA and protein were exclusively expressed in gastric cancer cells. The HERG protein was localized in the cytoplasm and membrane of the gastric cancer cells. The proliferation of gastric cancer cells expressing HERG protein was inhibited in a time- and dose-dependent manner...