Seeing the small picture

July 17th, 2014

U of T scientist uses tiny technology to aid in the fight against cancer

Sarah McDonald

This year’s McLean award winner Aaron Wheeler believes the solution to the colossal challenge of personalizing medicine for cancer patients may be a tiny one.

The McLean award is funded jointly by U of T alumnus William McLean and U of T’s Connaught Fund. The $100,000 prize is awarded annually to support outstanding basic scientific research at the University of Toronto in the fields of physics, chemistry, computer science, mathematics, engineering sciences, and the theory and methods of statistics.

Wheeler is an analytical chemist and professor at the University of Toronto whose research is primarily focused on digital microfluidics, a technology that allows scientists to work with minuscule volumes of fluids. Digital microfluidics takes a programming approach to microfluidics, allowing scientists to be precise in their work with tiny volumes of substances.

Among other advantages such as the ability to work with tiny, precious samples (tissue collected from a biopsy, for example), the ability to manipulate and study such tiny volumes of fluid makes it easier to work with three-dimensional clumps of cells, something Wheeler says could be beneficial particularly when developing treatment plans for people with cancer. “Everyone agrees across the board that we should all be culturing cells in three dimensions because cells grown in 3D are much more similar to cells grown in in vivo systems like humans. If I wanted to evaluate, say, how a drug interacts with cells, I’d like those cells to copy us as much as possible.”

Unfortunately, growing and working with cells in three dimensions creates unique challenges. “Coaxing the cells to grow is difficult. It often requires expensive reagents (external compounds or mixtures). You need some kind of gel scaffold for the cells to grow in, and some of those gels are expensive,” Wheeler explains.  “Some of those gels are very soft, such that you put those cells in them and you coax them to grow and then it all falls apart.”

This expense and difficulty in growing these cells means that despite the advantages of working in 3D, most scientists are still working primarily with 2D cells grown on dishes.

Wheeler and his team are hoping to change that. “We’ve developed a microfluidic platform that allows us to grow cells in three dimensions and to do it in an automated fashion,” he says.

Using their digital microfluidics technology, Wheeler’s team is able to grow 3D cells in tiny gel pockets and digitally program the delivery of reagents to the cells. “It turns out that that’s very gentle,” Wheeler explains.

“So even if I’m working with a soft gel, I can deliver fresh reagents. I can pull reagents away and the gel doesn’t fall apart, and the cells are happy. We think this is going to make it a lot easier for folks to do 3D cell culture.”

Wheeler’s next challenge, with the help of the Connaught award funding, is to apply this approach to designing cancer treatments. He plans to take biopsies of tumour tissue and use that tissue to grow cells on the digital microfluidics device where he can then test various drugs on the cells before giving them to the patient the biopsy was taken from.

“We’re going to look to find a personalized approach to treating that patient to find the combination of drugs and concentrations that’s perfectly tailored for that person. We can build this little device, take it into the doctor’s office, collect the sample, press a few buttons and ideally get some answers back. It tells us how to treat the patient,” he says.

“It’s a radical idea. We’re not the first to have it by any means. Personalized medicine is something that everyone’s talking about, but how do you implement it? No one’s really making it happen yet, and we think this may be an interesting way to make it happen.”

“Professor Wheeler’s work perfectly embodies the spirit of the McLean award,” says Judith Chadwick, U of T’s assistant vice president (research services).

“We are thrilled to recognize his achievements in a way that will help him continue his exciting research.”

Wheeler credits both the Connaught Fund and his team of researchers for the opportunity to move his unique approach to treating cancer patients forward. “It’s a phenomenal opportunity to work on this. This is such a kind of crazy, out-there idea. We might find it difficult to get this idea funded without the McLean Award,” he says.

“I’m very fortunate to work with an independent, creative group of people who have their own ideas and I’m always eager to follow them into areas that I initially don’t know much about, such as the biology of 3D cell constructs in tumour tissue. If this award is a recognition of my work, it certainly is a recognition of my research group and I’m eager to share that honour with them because they are a really amazing group of scientists.”

For more information on Wheeler and his Digital Microfluidics research, click here.

Professor Aaron Wheeler has won the 2014 McLean Award for his work in digital microfluidics. - Photo courtesy of the Faculty of Arts and Sciences

Professor Aaron Wheeler has won the 2014 McLean Award for his work in digital microfluidics. - Photo Diana Tyszko, Faculty of Arts and Science