Implantable device targets tumors using electric fields
Further to a list of side effects ranging from mildly unpleasant to just plain awful, the scattergun nature of chemotherapy often sees healthy tissue damaged along with the cancerous cells. Attacking these cancer cells with better precision would lead to more effective treatments and reduce harmful side effects, and has been a primary objective for researchers. Among this group is a team of scientists that has developed a way of administering cancer-fighting chemicals using an electric field that is claimed to enable a highly-targeted form of treatment.
"A big challenge with many drugs is getting them where they need to go," says Lissett Bickford, an assistant professor in the Department of Biomedical Engineering at Virginia Tech, one of the study's co-authors. "This technology basically forces drugs directly to and through the tumor, allowing all cancer cells in the treatment zone to get that exposure."
The technique, known as iontophoresis, involves a small device containing a reservoir of chemotherapy drugs that can be either implanted in the tumor or placed on the skin to create the electric field. In testing, mice suffering from human inflammatory breast cancer were treated with the iontophoresis method in addition to regular intravenous chemotherapy and experienced increased survival times compared with either treatment being administered on its own. Bringing radiation therapy into the mix served to boost this even further.
Also of note was that treating mice with iontophoresis after they had already been treated with intravenous chemotherapy served to boost the concentration of the drug in the tumor, while only bringing about a negligible difference in concentration in the blood plasma. Doing so could reduce common side effects of chemotherapy, which include everything from fatigue, to hair loss to nausea and vomiting.
The researchers say that the new technique has also proven to be effective at overcoming pressure built up around a tumor, a common complication in drug treatment strategies. This pressure is caused by leaks from the tumor blood vessels, which lead to a build up in fluid in the surrounding areas, making it more difficult to penetrate.
The new technique shows promise as a method that could complement more traditional forms of treatments. It could allow doctors to use more potent cancer-fighting drugs by localizing their effects, for example, or pave the way for new combinations of multi-drug cocktails by better aiming the more toxic compounds at the tumor and freeing the rest of the body from their harmful effects.
"This may ultimately lead to a reduction in the morbidity and mortality rates commonly found in different types of cancer," says first author of the study, James Byrne, a postdoctoral researcher and medical student at the University of North Carolina.
The research findings were published in the journal Science Translational Medicine.
Source: Virgina Tech