Researchers in the Department of Biology at York studied phenytoin, a drug which inhibits epilepsy by targeting sodium channels.
These channels, known as VGSCs, exist in the membranes of excitable cells, such as neurons, where they are involved in transmission of electrical impulses. They are also present in breast cancer cells where they are thought to help the spread of tumours.
In research published in Molecular Cancer, the York team found that "repurposing" antiepileptic drugs, such as phenytoin, that effectively block the sodium channels, could provide a novel therapy for cancer.
Despite extensive work to define the molecular mechanisms underlying the expression of VGSCs and their pro-invasive role in cancer cells, there is little clinically relevant in vivo data exploring their value as potential therapeutic targets.
The researchers found that treatment with phenytoin, at doses equivalent to those used to treat epilepsy significantly reduced tumour growth in a preclinical model. Phenytoin also reduced cancer cell proliferation in vivo and invasion into surrounding mammary tissue.
Dr Will Brackenbury, who led the research, said: "This is the first study to show that phenytoin reduces both the growth and spread of breast cancer tumour cells. This indicates that re-purposing antiepileptic and antiarrhythmic drugs is worthy of further study as a potentially novel anti-cancer therapy."
The research was funded by the Medical Research Council and the University of York. Some of the analysis was carried out by the proteomics team in the University's Bioscience Technology Facility. The research team also included Michaela Nelson, Ming Yang, Adam A Dowle and Dr Jerry Thomas.