"The gold nanoparticles have this ability to be activated by near-infrared lasers so that they can be heated quite rapidly," he says.

And Rosen adds that the nanoparticles travel to where they're needed, to the cancer, so the healthy tissue doesn't get heated up.

"You'll have those gold nanoparticles actually accumulating in the leaky blood vessels of the tumor, and then the laser can be used locally just to heat that area."

In this study, the tumor was heated to 42 degrees for 20 minutes. The actual target was breast cancer stem cells, the cells from which cancers grow and metastasize, and which tend to resist drug and radiation treatments.

Rosen says tests using laboratory mice suggest the heat treatments may be an effective way of augmenting radiation or chemotherapy for patients with some kinds of tumors, including breast cancer. But he cautions that it should not be considered a "magic bullet" in the fight against cancer.

"We think this is a proof of principle, that this type of approach will work, but it's a bit like the gene therapy field was maybe 15 years ago — we're going to have to still target to the right cells and the right place."

Baylor College of Medicine researcher Jeffrey Rosen's paper is published in the journal Science Translational Medicine.