Zapping cancer cells with magnets

October 10, 2012

Magnet setup showing a simulated magnetic field pattern. The sample region where cells are placed is indicated. (Credit: Mi Hyeon Cho, et al./Nature Materials)

Magnetic nanoparticles can be used to kill cancer cells by controlling cell signaling pathways, researchers from Yonsei University in South Korea have demonstrated.

They developed magnetic nanoparticles that turn on apoptosis cell signaling (commands to kill cells) in cancer cells by using a remote, non-invasive magnetic field.

The magnetic switch uses zinc-doped iron oxide magnetic nanoparticles (Zn0.4Fe2.6O4), combined with a targeting antibody for death receptor 4 (DR4, a protein on the surface of certain cells — in this case. of colon cancer cells).

When a magnetic field is “on” (applied to aggregate magnetic nanoparticle-bound DR4s), it promotes apoptosis signaling pathways (kills the cell).

The researchers tried the approach with a dish of colon cancer cells. Within 24 hours, more than half of the cells exposed to the magnetic field were dead, the team reports online October 7 in Nature Materials.

They also demonstrated that the magnetic switch is operable at the micron (millionth of a meter) scale and that it can be applied in an in vivo (live) system to induce apoptotic morphological (shape) changes in zebrafish.


a, Bright field image of zebrafish with magnetic field application only. b, fluorescence image. (Credit: )