The safety and efficacy of magnetic nano-iron hyperthermia therapy on rat brain glioma.

Gliomas are a group of heterogeneous primary central nervous system tumors arising from glial cells. These tumors are associated with high morbidity and mortality. New opportunities for the development of effective therapies for malignant gliomas are urgently needed. Magnetic nano-particles can heat up tumor tissues and induce the killing of cancer cells. However, the in vivo action of magnetic nano-iron hyperthermia on brain gliomas has not been widely investigated. The safety, efficacy, and suitable dose of hyperthermia therapy remain unknown. We successfully established a rat model of brain glioma by injecting C6 glioma cells into the right caudate nuclei of rats. Fixed doses (2.5, 5, or 10 mg) of magnetic nano-iron were then injected into the tumors of tumor-bearing rats. The survival time of tumor-bearing rats was subsequently observed, and imaging studies were conducted on the brain tumors. Of the 80 rats that underwent C6 glioma cell implantation, 70 exhibited decreased mobility and appetite, and wasting. Establishment of this brain glioma model was confirmed to be successful by magnetic resonance imaging. After injection of different doses of magnetic nano-iron, the survival times of the different dose groups of tumor-bearing rats were not significantly different. However, the tumor size exhibited a significant decrease with magnetic nano-iron hyperthermia therapy. Injection of various doses of magnetic nano-iron was safe in tumor-bearing rats. The effective doses were 2.5 and 5 mg. Magnetic nano-iron hyperthermia significantly shrank the brain gliomas in tumor-bearing rats.