National Cancer Institute funds new nanotechnology center

Sam Gambhir

Imagine if a device were small enough to slip into living cancer cells and report on what's going on inside of them. The National Cancer Institute has envisioned just this scenario and has established eight centers for honing the tiny tools of nanotechnology—devices that can be 1/10,000th of a cross-section of human hair—to reveal, monitor and treat cancer. One of these Centers of Cancer Nanotechnology Excellence is to be based at the medical school.

On Feb. 27, the NCI announced that it has allotted roughly $20 million over five years to a center to be led by professor of radiology and bioengineering Sanjiv Sam Gambhir, MD, PhD, who directs the Molecular Imaging Program at Stanford. Associate professor of materials science and of electrical engineering Shan Wang, PhD, will be working closely with him on this grant.

NCI Centers of Cancer Nanotechnology Excellence are research alliances of cancer centers, medical institutions, schools of engineering and physical sciences, nonprofit organizations and private corporations. Their mission is to integrate nanotechnology into cancer research. "It's the team science approach," said Gambhir.

The groups that will be included with the Stanford Center for Cancer Nanotechnology Excellence Focused on Therapy Response are: UCLA, Cedars-Sinai Medical Center, Fred Hutchinson Cancer Research Center, the University of Texas-Austin, General Electric Global Research and Intel Corp. Within Stanford, faculty from the Schools of Humanities & Sciences, Engineering and Medicine will combine their collective expertise to develop novel methods to use nanotechnology to detect cancer and evaluate therapies. In addition, outreach to the community will be done through the Canary Foundation, which is focused on early cancer detection.

"There's a shift in science and medicine now toward saying 'Look, we can't just have individual labs doing their individual research,'" said Gambhir. "This is the other extreme—a large diverse team of scientists and physicians."

The team, said Gambhir, was chosen to represent scientists from more than a dozen disciplines, including chemistry, materials science, cancer biology, immunology, clinical oncology, radiology and molecular imaging. He added that more than half of the team has already been actively involved in nanotechnology research, and that the new center gives them the opportunity to interact with investigators whose primary focus is cancer research.

"The first year, the biggest challenge is going to be getting these people working together," he said, referring to how unusual it is for people of such divergent scientific backgrounds to be collaborating. "It involves people speaking different languages."

Gambhir's background has prepared him to lead such an interdisciplinary venture. He has training in physics, applied mathematics, cell and molecular biology, medicine, nuclear medicine and molecular imaging. He runs a research lab in the Clark Center and sees patients in the nuclear medicine clinic.

The Stanford center will not be developing nanodevices that will be used to treat people. It will aim its efforts at either imaging disease (in vivo) or detecting what is going on inside patients by evaluating blood or tissue samples (ex vivo, or in vitro).

"There are a lot of people at work already on in vitro diagnostics—taking blood and other samples and trying to determine what disease state you are in—and others who are involved with in vivo molecularly imaging a living person," Gambhir explained. "The marriage between the two subdisciplines gives this grant a lot of potential." In its grant application, the group wrote, "Either the ex vivo or in vivo strategy alone will not be optimal; both together will likely provide significant synergy."

Gambhir's work to date has focused on the in vivo side, working on new molecular imaging strategies for small animals and patients. Becoming involved with a nanotechnology center will add another aspect to his multipronged attack on uncovering the mysteries of the things that go wrong in cancer.

Gambhir's lab has already begun exploring some of the frontiers of nanotechnology research, progressing the furthest with quantum dots, or qdots—tiny crystals that have pieces of protein attached to their surfaces that allow them to latch on to cancer cells and produce multicolored signals.

Much of his current work using qdots is in predicting and monitoring the response to therapy in animal models. He said that this work should lead to new ways to test drug efficacy in small-animal cancer models, thereby accelerating the process of bringing better drugs to the clinic.

If approved for human use, the same nanoparticles should also become useful for assessing a patient's response to therapy and in the early diagnosis of cancer, when maybe only a few cells are cancerous. The best methods available now can detect cancer only when a million or so cells have turned malignant.

Gambhir and his team of more than 15 research labs will pursue a number of avenues for diagnosing cancer, in ways that Gambhir said he couldn't even imagine yet. "Just by bringing these teams of scientists together in our planning meetings," he said, "we have come up with ideas for going after cancer detection that we would not have thought of individually."

The center will receive $3.83 million for 2006, with the NCI to decide later the exact amount for each remaining year. Other Stanford researchers involved in the project are: Hongji Dai of the Department of Chemistry; Rob Tibshirani of the Departments of Health Research & Policy and of Statistics; Michael Kelly, Bob Sinclair and Robert Wilson of the Department of Materials Science and Engineering; Dean Felsher and P.J. Utz of the Department of Medicine; Garry Nolan of the Departments of Microbiology & Immunology and of Molecular Pharmacology; Xiaoyuan Chen, Samira Guccione, David Paik, Sylvia Plevritis, Jianghong Rao and Meike Schipper of the Department of Radiology, and Ed Myers, Yoshio Nishi and Mary Tang of the Stanford Nanofabrication Facility.