Big grant for small science
By Jim Oldfield
Dr. Robert Nam was one of many who noticed Dr. Shana Kelley's 2009 Nature Nanotechnology paper on cancer-detecting microchips-Scientific American covered the publication; Peter Mansbridge interviewed Kelley for "Mansbridge One On One"-but he was one of the few to launch a collaboration based on it.
Kelley, a professor in the departments of biochemistry and pharmaceutical sciences at the University of Toronto, and Nam, a clinical epidemiologist at Sunnybrook Research Institute (SRI) and head of the genitourinary cancer group at the Odette Cancer Centre, turn down more offers to collaborate than they initiate. But when Nam approached Kelley about working together, they each found a match.
"Boom. It just fell into place," says Nam, who is also an associate professor of surgery at U of T. "Our goals were the same."
The main goal the two shared was to transform prostate cancer screening. Now, the Canadian Institutes of Health Research has awarded them an emerging team grant to do just that.
Worth $1.6 million over four years, the grant will fund a team led by Nam and Kelley that includes Dr. Ted Sargent, Canada Research Chair in Nanotechnology and Dr. Aaron Wheeler, Canada Research Chair in Bioanalytical Chemistry, both faculty at U of T. Nam and colleagues will refine Kelley's microchip technology to develop a prostate cancer screening device that is fast, inexpensive and noninvasive.
The technology consists of finely structured electrode probes, grouped into blossoms and arrayed on a chip of silicon. Each probe is coated in molecules designed to bind with the ribonucleic acid in cancer cells. The chip enables detection of small numbers of circulating cancer cells--a feat previously possible only with a roomful of computer technology.
The chip's sensitivity is a major breakthrough, but a remaining challenge is specificity: it must distinguish cancer cells from an increasingly complex background of molecular material, as the researchers shift their experiments from cancerous cell lines to human tissue biopsies and blood.
To detect prostate cancer reliably, and to establish whether it is slow-growing or aggressive, the researchers will need a well-developed panel of prostate-cancer-specific biomarkers. Nam will look for those markers-which he and other scientists are discovering with increasing efficiency-using SRI's newly acquired next-generation DNA sequence analyzer and Sunnybrook's tumour bank. Meanwhile, Kelley, Sargent and Wheeler will streamline the chip-based nanotechnology. If all goes according to plan, says Nam, "We can throw out the PSA [prostate-specific antigen] test."
The PSA test is the standard noninvasive screening tool for prostate cancer, but its accuracy is limited. Moreover, it doesn't discriminate between slow-growing and metastatic cancer-a crucial distinction for catching aggressive forms of the disease at a treatable stage and making therapeutic decisions. "Watchful waiting," for example, where a physician closely monitors a patient for signs of disease progression, is often a better choice for preserving quality of life than are radical alternatives like surgery.
Despite the tantalizing promise of better screening, Kelley says clinicians need to decide if they're willing to adopt new diagnostics like the microchip. Having a clinical collaborator like Nam, she says, helps her understand the challenges in gaining acceptance for her technology, and provides a critical link to the community that she hopes will use it.
"Rob is a great collaborator because he is so excited about the science-the potential for impact-and he's the right combination of pushy but realistic in terms of timelines," says Kelley. "He always has good ideas about the next step. For me it's been just a fantastic new relationship."
