Journal Image
Recent Patents on Anti-Cancer Drug Discovery
ISSN (Print): 1574-8928
ISSN (Online): 2212-3970
DOI: 10.2174/1574892811308010066

Persistent Current Blockers of Voltage-Gated Sodium Channels: A Clinical Opportunity for Controlling Metastatic Disease

Author(s): Mustafa B.A. Djamgoz and Rustem Onkal
Pages 66-84 (19)
A range of experimental and clinical data suggests strongly (i) that metastatic progression in carcinomas is accompanied (maybe even preceded) by upregulation of functional voltage-gated sodium channels (VGSCs) and (ii) that VGSC activity enhances cancer cell invasiveness. First, this review outlines the available in vitro and in vivo evidence for the VGSC expression and its proposed pathophysiological role. Second, we question the mechanism(s) whereby VGSC activity can induce such a cancer-promoting effect. We advance the hypothesis that it is the hypoxia-sensitive persistent component of the VGSC current (INaP) that is central to the phenomenon. Indeed, blockers of INaP are very effective in suppressing cancer cell invasiveness in vitro. Based upon these data, UK and international patent applications have been filed which describe the use of INaP blockers, like ranolazine (“Ranexa”) and riluzole (“Rilutex”), as anti-metastatic agents. Importantly, since these drugs are already in clinical use, against conditions like cardiac angina and amyotrophic lateral scelerosis, there are no issues of dosage, unacceptable side effects or long-term use. Thus, INaP blockers have the potential to turn cancer into a chronic condition.
Hypoxia, metastasis, persistent current, ranolazine, riluzole, voltage-gated sodium channel
Division of Cell & Molecular Biology, Neuroscience Solutions to Cancer Research Group, Sir Alexander Fleming Building, South Kensington Campus, Imperial College London, London SW7 2AZ, UK.