Tiny gold rods could be used to attack hard-to-reach cancers
May 16, 2013 | by Nicole White
Gold has been used for jewelry, to fill teeth and to garnish desserts. Now, the precious metal may also prove to be an important tool for fighting cancer.
Already, doctors have many ways to kill cancer cells. The trick is not damaging the rest of the body in the process, says Jacob Berlin, Ph.D., an assistant professor in the Department of Molecular Medicine at City of Hope.
Thermal ablation – zapping tumors with intense heat – is one strategy that has shown considerable promise. But like other physical strategies, it requires probes or other means to access the cancer site. And in some cases, the tumor cannot be reached or may have spread, creating stray malignant cells. In other cases, there may be many tumors.
Now, working with researchers in the laboratory of Karen Aboody, M.D., an associate professor in the Department of Neurosciences and the Division of Neurosurgery, Berlin and his colleagues believe they’ve found a method of delivering blasts of thermal ablation directly to tumor sites, using tiny gold rods embedded in neural stem cells.
The strategy is outlined in a paper published by, and soon to be featured on a cover of, Advanced Healthcare Materials. It builds on pioneering work by Aboody showing that neural stem cells migrate naturally to tumor sites. This natural tendency makes the cells an excellent vehicle for the gold nanorods, which are about the size of a virus.
There’s much to like about gold, therapeutically speaking. Gold is nontoxic, and gold nanoparticle rods are relatively easy to make. Most important, the rods vibrate at a certain frequency, which turns them into tiny antennae.
This frequency allows physicians to use a special laser that targets only those spots where the nanorods are vibrating – leaving the healthy tissue unharmed.
So far, Berlin, Aboody and their team have demonstrated the promise of this method in cell models and mouse models of breast cancer. They were able to show that the gold nanorods could be carried by the neural stem cells without affecting the cells’ ability to naturally migrate to cancer cells. Further, they were able to show that the rods would heat up sufficiently to ablate the surrounding cancerous tissue.
Ultimately, the method could prove valuable for treating not just breast cancer but other types of cancer as well, such as head and neck, bladder and ovarian.
The work was supported by STOP CANCER, the Rosalinde and Arthur Gilbert Foundation, Mary Kay Foundation, California Institute of Regenerative Medicine, the Alvarez Family Foundation and the Accelerated Brain Cancer Cures Foundation.