Nearly complete regression of tumors via collective behavior of magnetic nanoparticles inhyperthermia

Abstract

One potential cancer treatment selectively deposits heat to the tumor through activation ofmagnetic nanoparticles inside the tumor. This can damage or kill the cancer cells withoutharming the surrounding healthy tissue. The properties assumed to be most important forthis heat generation (saturation magnetization, amplitude and frequency of externalmagnetic field) originate from theoretical models that assume non-interactingnanoparticles. Although these factors certainly contribute, the fundamental assumption of‘no interaction’ is flawed and consequently fails to anticipate their interactions withbiological systems and the resulting heat deposition. Experimental evidence demonstratesthat for interacting magnetite nanoparticles, determined by their spacing and anisotropy,the resulting collective behavior in the kilohertz frequency regime generates significantheat, leading to nearly complete regression of aggressive mammary tumors in mice.