Using magnets to deliver cancer drugs

Being able to deliver cytotoxic agents directly to a tumor is a longstanding goal of oncologists. A new technique that relies on magnets is now being tested by Sylvain Martel of École Polytechnique de Montréal and a team of researchers from the Université de Montréal.

Using magnets to deliver drugs is not a new idea. The trouble is that as the drugs are needed deeper inside the body, the magnetic field used to steer them becomes less powerful. The Montreal researchers evaded this problem by using an upgraded MRI scanner and specially designed ‘therapeutic magnetic microcarriers’ (TMMC). The TMMC are essentially tiny biodegradable balls loaded with both magnetic nanoparticles and a drug.

In a proof of concept test published in Biomaterials, the scientists were able to send TMMC loaded with the anti-cancer drug doxorubicin through a live rabbit’s bloodstream and directly to a predetermined target site in the animal’s liver. The doxorubicin was successfully released at that site.

Left: Navigation using magnetic resonance in the hepatic artery.

Right: Image of liver using magnetic resonance.

Blue dots represent therapeutic magnetic microcarriers (TMMC);

+ represent anticancer agents;

Red oval is part of the liver (foie in French);

Red bar is the catheter

Credit: Image courtesy of Polytechnique Montréal.

Obviously, this work is still in the early stages. It’s hard to extrapolate data from tests with rabbits to predict how the technique will fare in human trials. Still, I don’t doubt that human trials are on the horizon for magnetic drug targeting.