Living cells consist of ions, charged molecules, membranes and organelles, which are responsive to electrical fields and currents and sometimes even generate electrical activity. When a non-uniform electric field is generated near living cells, polar molecules will move towards the higher field intensity. When an altering current is generated the molecules stay in place, their reaction being only vibration. However, in dividing cells the altering field causes the molecules to move towards the furrow, which is the narrow place between the two daughter cells. Using this principle the scientists had a way to tell apart normal cells from dividing cells, which are normally cancerous cells.
The procedure achieved good results when tested on tissue cultures and animal tumors. When tried on several cancerous tissue cultures the treatment was found effective. While the control culture roughly doubled itself every 24 hours, the exposed cultures’ proliferation rate was slowed down. After its efficiency was proved on culture, the treatment was tried on a living animal. Rats with Intracranial Glioblastoma, a type of brain cancer, were used to test the treatment. A group of rats were treated with an electric field while another one was kept as control. The rats treated with the electric field showed a tumor half the size of the control on average after a treatment of six days. The successful results led to clinical tests.
The treatment then was successfully tested on human Glioblastoma multiforme (GBM), a deadly form of brain tumor. Ten patients, all with recurrent GBM were treated using the method. The patients treated showed continued living more than twice longer than other patients suffering from GBM, and at least in one case ten months after the treatment the tumor wasn’t detected using MRI. Other clinical tests with the new method are currently underway.
The treatment is supposed to have very few side-effects and since it is done using external electrodes it is non invasive. The risks include seizures or cardiac arrhythmias, but since the frequency used is larger than 10kHz no such side-effects are expected to happen. Current cancer treatments that target dividing cells, such as chemotherapy or radiotherapy have the problem of killing frequently dividing normal cells like bone marrow cells. Because the bone protects the bone marrow from electrical charges, the AC electric charge will have a significantly lower affect (100 fold less!) on the bone marrow than in other treatments where the cells are not protected by the bone. Using electrical fields seems to be a promising way to cure cancer, being both effective and free of side-effects.
In 2006, TFOT covered a similar research conducted by Luca Cucullo and Damir Janigro from the Cleveland Clinic Lerner College of Medicine in Ohio. In their study, tumor cells resistant to chemotherapeutic drugs were subjected to very low intensity electrical stimulation. As a result, these cells acquired sensitivity to the anti-cancer drug doxorubicin. The hope now is that combination of electrical stimulation and chemotherapy will result in better treatment for cancer patients.
More information on the recent Technion research can be found on the PNAS magazine.