Magnetic fields could guide experimental cancer-killing viruses to tumours

In collaboration with the Press Association
Visualising a magnetic field (Image from Flickr)

A new technique using magnetic fields from an MRI scanner to move cancer-fighting viruses towards tumours could improve an experimental cancer treatment, according to UK scientists.

“It’s a fascinating idea - but more studies are needed to see if this approach could work in people"Dr Nick Peel, Cancer Research UK

MRIs are not normally used to treat cancer. They are generally used to provide an image of the tumour, giving information about its size and location.

The new technique involves adding tiny magnetic particles – called super-paramagnetic iron oxide nanoparticles – to modified immune cells that carry the virus, then uses magnets to direct them to the tumour.

In studies with mice, the researchers from the University of Sheffield discovered that the MRI scanner improved delivery of these magnetic cells to tumours in the prostate and tumours that had spread to the lungs. 

The study used a virus – called an oncolytic virus – held within a type of immune cell called a macrophage. The macrophage delivers the virus, which can then infect and kill the cancer cells.

Publishing their findings in the journal Nature Communications, the researchers found that, when they guided the virus-carrying immune cells towards prostate tumours in mice, it caused tumours to shink more effectively than if no guidance was used. 

Dr Nick Peel, senior science information officer at Cancer Research UK, said: “Using viruses to kill tumour cells is one of many ways researchers are using the immune system to attack cancer. But getting the virus precisely on target is a real challenge.” 

And Dr Munitta Muthana, an author on the study, said the team’s findings could help overcome this.

"Our results suggest that it is possible to use a standard MRI scanner to naturally deliver cell-based therapies to both primary and secondary tumours which would normally be impossible to reach by injection,” she said.

But Dr Peel cautioned that while the approach was interesting, it was still in its early stages, and further work would be needed before this could benefit patients.

“It’s a fascinating idea - but more studies are needed to see if this approach could work in people, especially for tumours located deeper within the body,” he said.

“And we need even more research to show whether this could actually improve treatment.”

References

  • Muthana, M., et al. (2015). Directing cell therapy to anatomic target sites in vivo with magnetic resonance targeting Nature Communications, 6 DOI: 10.1038/ncomms9009