A nanotech approach to overcoming the resistance of some cancer cells to radiation therapy has been successfully tested in mice. From the National Cancer Institute's Alliance for Nanotechnology in Cancer "Nanoparticle-Induced heating boosts antitumor radiation therapy":

Radiation therapy is a time-honored and effective component of modern cancer therapy, but its ultimate utility is limited by the fact that some cancer cells are resistant to ionizing radiation. Now, a research team led by Sunil Krishnan, M.D., of the University of Texas M.D. Anderson Cancer Center, has found that pretreating tumors with gold nanoparticles and near-infrared radiation dramatically improves the response of tumors to radiation therapy.

Reporting its work in the journal Nano Letters [abstract], the Texas investigators showed that inducing a mild temperature rise in tumors increases blood flow throughout tumors, particularly in those regions of a tumor that are normally deprived of oxygen that results from the disrupted network of blood vessels found deep within tumors. To produce the mild temperature rise, or hyperthermia, the researchers used gold nanoparticles and infrared light. Gold nanoparticles become warm, or even hot, when irradiated with near-infrared light, an effect that other researchers are exploring as an anticancer therapy.

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