Glowing nanoparticles could light the way for cancer treatments
The U.S. Food and Drug Administration has approved the first human clinical trials of a diagnostic tool that uses nanoparticles to light up cancer cells, making it easier to find and treat small-cell cancers such as mesothelioma.
The technology uses Cornell Dots – tiny silica particles that glow when exposed to near-infrared light, serving as a beacon to identify targeted cancer cells. According to research to be published in the July issue of the Journal of Clinical Investigation, the technology can guide surgeons to the cancer as well as reveal the spread of the disease to lymph nodes and other organs in the body. The technology can also show how the cells respond to treatment.
Cornell Dots, also known as C dots, were developed in 2005 by Hooisweng Ow, then a graduate student at Cornell University, and Ulrich Wiesner, the Spencer T. Olin Professor of Materials Science and Engineering at Cornell.
A single C dot consists of dye molecules encased in a chemically inert silica shell as small as 5 nanometers in diameter (a nanometer is one-billionth of a meter). The dots are coated with polyethylene glycol, which prevents them from being recognized by the body as foreign substances, giving them more time to find targeted tumors.
Small enough to pass through the body and out in urine, the C dots may also be able to deliver radioactivity or drugs to tumors.
The current research is a collaboration between Cornell University, Sloan-Kettering Institute for Cancer Research and Hybrid Silica Technologies, an Ithaca, NY company started by Ow and Wiesner to commercialize the C dot technology.
The clinical trials will involve five patients at Sloan-Kettering and will seek to verify that the technology is safe as well as to provide data that will guide future applications. The dots will be labeled with radioactive iodine, which makes them visible via positron emission tomography, or PET scans, to show how many dots are taken up by tumors and where else in the body they go and for how long.
Michelle Bradbury, a radiologist at Sloan-Kettering Institute for Cancer Research and assistant professor of radiology at Weill Cornell Medical College, said the trials will mark the first FDA-approved use of inorganic material in the same manner as a drug in humans.
"This is the first product of its kind. We want to make sure it does what we expect it to do," Bradbury said.