Erasing Boundaries (pdf)

Measure a human cell in meters, and its diameter will be about 10,000 to 20,000 nanometers. A nanometer is one billionth of a meter. Now, try to create a tool that works in that cell-a tool as small as 50 or 100 nanometers in size-and you begin to explore the possibilities of nanotechnology. That's what scientists, engineers, and clinicians from across Dartmouth are doing-joining forces and combining expertise to build incredibly tiny structures-because their potential for cancer medicine is huge.

"Nanotechnology will change the future of cancer diagnosis and treatment," says Dr. Mark Israel, director of Norris Cotton Cancer Center. "In the past ten years, we have learned a tremendous amount about cancer genetics, and the processes that change normal cells to cancerous ones. Using nanotechnology, we can develop tools to attack those processes- and turn the latest discoveries in cancer biology into promising new therapies for cancer patients."

Drs. Ursula Gibson and Jack Hoopes are working together to develop nanoparticles to be used in both imaging and treatment.

Ursula Gibson, an associate professor of engineering at Thayer School, has been interested in the possibilities of nanotechnology for awhile now. With colleagues from chemistry and physics, Gibson started the Center for Nanomaterials Research at Dartmouth eight years ago. She is interested in the ways materials can be manipulated at the atomic level to change the way they behave. "We're using known or plausible chemical reactions to change the structure of materials on a very fine scale, so that we can do things with those materials that might not otherwise be possible."

When Dr. Israel approached her about applying her knowledge to cancer, Gibson didn't need much convincing. She did need to learn the language of cancer biology to communicate with a diverse group of collaborators. "So many people are willing to go beyond their comfort zone to work with us," she says.

Gibson is working with professor of chemistry, Joseph Belbruno, to develop a nanoparticle through a process called molecular imprinting-molding a polymer to fit a molecule that's expressed in cancer cells. The result is an artificial antibody designed to attach to an antigen common in tumor cells. "Just being able to make something that attaches to the antigen isn't enough," Gibson says. "It has to be able to make it through the blood stream and penetrate the tumor, so we're working with people who can include contrast agents in our polymers, and with magnetic resonance imaging (MRI) expertise, so we can watch the particles go through the blood stream. It's an incredibly challenging project."

"Innovative collaborations between engineers and clinical researchers at Dartmouth are not unusual," says Jack Hoopes, associate professor of surgery and medicine at Dartmouth Medical School and adjunct professor of biomedical engineering at the Thayer School. "Imaging is a common and important area of focus in the Cancer Center's nanotechnology projects. We want to be able to see the nanoparticles before, and possibly even after, cancer treatment. This will give us a much better understanding of the location and volume of the tumor, and ultimately, the role that the nanoparticles play in treatment outcome."