Researchers have initiated animal trials for a potential cancer treatment using nanotechnology. The early results are promising. In the experiment, nanoshells built to heat up under a specific near-infrared frequency were injected into groups of mice with cancerous tumors in their tissues. After a few hours the skin above the tumors were irradiated with a near-infrared laser. The nanoshells apparently migrated to diseased tumor cells rather than healthy cells and killed these cells as they heated up. The healthy tissue around the tumors was unaffected.