Anti-Epilepsy Drug May Reduce Cancer Spread

Repurposing drugs that block sodium channels may offer a novel therapy for cancer.

A drug widely used to treat epilepsy may also be effective in halting the spread of cancer, according to a recent study.

Recently published in Molecular Cancer, the study examined how the use of phenytoin could potentially reduce the growth and spread of breast cancer. The drug is able to inhibit epilepsy by blocking sodium channels.

These channels, called VGSCs, are located within the membranes of excitable cells, such as neurons, where they play a role in transmitting electrical impulses. These channels are also found in breast cancer cells and are believed to halt the spread of tumors.

The researchers found that repurposing anti-epilepsy drugs may effectively block the sodium channels, which subsequently provides a novel cancer therapy.

While extensive prior research has been performed in defining the molecular mechanisms for the expression of VGSCs and their “pro-invasive” role in treating cancer cells, little clinically relevant in vivo data has been extrapolated regarding their value as potential treatment targets.

In the current study, researchers found that doses of phenytoin that are equivalent to those used in epilepsy treatment significantly decreased tumor growth in a preclinical model. Additionally, phenytoin reduced the proliferation of cancer cells in vivo and the invasion into surrounding mammary tissue.

"This is the first study to show that phenytoin reduces both the growth and spread of breast cancer tumor cells,” lead researcher Will Brackenbury, MD, said in a press release. “This indicates that re-purposing antiepileptic and antiarrhythmic drugs is worthy of further study as a potentially novel anti-cancer therapy."