ArticleNaunyn-Schmiedeberg's archives of pharmacology2003
Inhibition of cloned HERG potassium channels by the antiestrogen tamoxifen.
Article in Naunyn-Schmiedeberg's archives of pharmacology, 2003. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers.
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Who cites it
22 citing papers in PubMed, 49 citations in OpenAlex.
- Hydrogel-Based Delivery of Ion Channel Modulators for Cancer Therapy: Current Advances and Future Perspectives.Gels (Basel, Switzerland) · 2026Review
- Drug Proarrhythmic Evaluation in a High Throughput Cardiac New Approach Methodology.bioRxiv : the preprint server for biology · 2026Article
- Effect of VSOR/VRAC blocker tamoxifen on contractile activity of primary neonatal cardiomyocytes and isolated perfused heart.BMC research notes · 2026Article
- Bazedoxifene and Beyond: Identifying This SERM's Targets and Deciphering Its Molecular Mechanisms.Advances in pharmacological and pharmaceutical sciences · 2026Review
- Blocking the voltage-gated sodium channel hNaFEBS open bio · 2025Article
- Review
- Enhancing Tamoxifen Therapy with α-Mangostin: Synergistic Antiproliferative Effects on Breast Cancer Cells and Potential Reduced Endometrial Impact.Pharmaceuticals (Basel, Switzerland) · 2023Article
- Targeting Ion Channels for Cancer Treatment: Current Progress and Future Challenges.Reviews of physiology, biochemistry and pharmacology · 2022Review
- Focus on Triple-Negative Breast Cancer: Potassium Channel Expression and Clinical Correlates.Frontiers in pharmacology · 2020Review
- The Risk of QTc-Interval Prolongation in Breast Cancer Patients Treated with Tamoxifen in Combination with Serotonin Reuptake Inhibitors.Pharmaceutical research · 2019Article
- Increased long QT and torsade de pointes reporting on tamoxifen compared with aromatase inhibitors.Heart (British Cardiac Society) · 2018Article
- Anticancer drugs-related QTc prolongation, torsade de pointes and sudden death: current evidence and future research perspectives.Oncotarget · 2018Review
- Review
- hERG1 Potassium Channels: Novel Biomarkers in Human Solid Cancers.BioMed research international · 2015Review
- HERG K+ channel-dependent apoptosis and cell cycle arrest in human glioblastoma cells.PloS one · 2014Article
- Mechanisms of zolpidem-induced long QT syndrome: acute inhibition of recombinant hERG K(+) channels and action potential prolongation in human cardiomyocytes derived from induced pluripotent stem cells.British journal of pharmacology · 2013Article
- Voltage-dependent open-channel block of G protein-gated inward-rectifying K(+) (GIRK) current in rat atrial myocytes by tamoxifen.Naunyn-Schmiedeberg's archives of pharmacology · 2012Article
- Identification of quaternary ammonium compounds as potent inhibitors of hERG potassium channels.Toxicology and applied pharmacology · 2011Article
- Prognostic significance of hERG1 expression in gastric cancer.Digestive diseases and sciences · 2010Article
- Inhibition of cardiac HERG currents by the DNA topoisomerase II inhibitor amsacrine: mode of action.British journal of pharmacology · 2004Article
Corrections and comments
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Authors and funding
12 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Tamoxifen is a nonsteroidal antiestrogen that is commonly used in the treatment of breast cancer. Although antiestrogenic drugs are generally believed not to cause acquired long QT syndrome (LQTS), concerns have been raised by recent reports of QT interval prolongation associated with tamoxifen treatment. Since blockade of human ether-a-go-go-related gene (HERG) potassium channels is critical in the development of acquired LQTS, we investigated the effects of tamoxifen on cloned HERG potassium channels to determine the electrophysiological basis for the arrhythmogenic potential of this drug. HERG channels were heterologously expressed in Xenopus laevis oocytes, and currents were measured using the two-microelectrode voltage clamp technique. Tamoxifen blocked HERG potassium channels with an IC(50) value of 45.3 microM. Inhibition required channel opening and unblocking occurred very slowly. Analysis of the voltage-dependence of block revealed loss of inhibition at positive membrane potentials, indicating that strong channel inactivation prevented block by tamoxifen. No marked changes in electrophysiological parameters such as voltage-dependence of activation or inactivation, or inactivation time constant could be observed, and block was not frequency-dependent. This study demonstrates that HERG potassium channels are blocked by the antiestrogenic drug tamoxifen. We conclude that HERG current inhibition might be an explanation for the QT interval prolongation associated with this drug.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.