Cyclotrons, radioisotopes, positron emission tomography, golden nanocages—no, we're not describing the set of the next Star Trek. These are all part of Dr. Michael Welch's pioneering history in the imaging field. When the professor of radiology was recruited to Washington University School of Medicine over 40 years ago, he worked with the first cyclotron installed for medical use in a medical school in United States, using radioisotopes for positron emission tomography (what's used to detect breast cancer and other tumors today). Now Welch is working on research, funded largely by the National Institute of Health, that will again change how we see cancer—but this time, the research focuses on treatment rather than detection.
Working with Dr. Younan Xia, Welch is researching nanoparticles and their application in the diagnosis and treatment of cancer. Using an injection of golden nanocages—small golden boxes that collect selectively in tumors—the team is testing mice. Theoretically, once the nanocages collect in high enough concentrations in the tumors, a laser can be used to heat and destroy the nanocages and, thus, the tumors. "It is in the realm of possibility that this could be a new approach to cancer therapy by destroying cells this way," says Welch. "There's an enormous amount of potential." The method is called passive targetting, where nanocages collect on tumors close to the service in smaller concentrations. Next, the researchers hope to apply higher concentrations of nanocages in tumors by attaching personal molectules to the nanocages, which will then bind to receptors and antigens.
"There is a lot of talk of personalized medicine, and we are finally on the road to truly implement that," says Welch. "We just have to get the gold to the tumor. So far the results have been pleasing."
