Toronto, ON – University of Toronto biomedical engineering professor Molly Shoichet has been named the L’Oréal-UNESCO For Women in Science North American laureate for 2015.
Already the only person ever elected to all three of Canada’s science academies and a university professor (the highest distinction U of T awards its faculty), Shoichet is the senior advisor to the U of T president on science and engineering engagement. She is also the innovative mind behind breakthroughs ranging from ‘space suits’ for fragile stem cells to polymer-based ‘vehicles’ that could let cancer drugs ‘drive’ to affected areas.
The award – which includes a $140,000 prize – recognizes accomplished female researchers and encourages more young women to enter science and technology careers.
“Since I can remember, my mom encouraged me to have a profession,” says Shoichet. “I did well in math and science in high school and was lucky to be able to dream about what I could contribute. Now I’m following that dream for a living.”
For Shoichet, the key to that dream lies in Jell-O-like materials called hydrogels – networks of polymer chains that swell in water, can thin and flow when forced through a needle, and then set almost immediately. These hydrogels allow stem cells or drugs a better chance of getting to and integrating into the parts of the body where they’re needed.
“If you have a series of wires that are all broken, just throwing in more wires won’t fix things,” says Shoichet. “In the nervous system, for example, we need those wires to be connected to a circuit to work…. We need the stem cells to survive long enough to integrate, but we need the cells to integrate in order to survive.”
Shoichet and her team have solved this chicken-and-the-egg dilemma with a delivery system that acts as a sort of space-suit, incorporating fragile stem cells in a hydrogel that has survival-promoting ‘life-support’ cells inside the gel. This enables the stem cells to survive long enough to give them a fighting chance to integrate – a stage which most stem cells implanted into the body fail to reach.
Such transplants could someday lead to treatments for spinal cord injuries, stroke and blindness, to name a few – where hydrogel-based ‘vehicles’ could transport specifically-engineered cell groups more safely directly to damaged tissue that needs repairing.
Shoichet and team are also designing polymers to deliver specially-engineered nano-scale drugs to specific areas of the brain and spinal cord, stimulating existing stem cells to mend damaged tissue.
To do this without damaging the brain or spinal cord, Shoichet and her colleagues take a hydrogel containing the stem-cell-stimulating drug and nano-spheres filled with an additional drug to slow the release of the stem-cell-stimulating drug and inject it directly on top of the brain or spinal cord for a local, sustained release to the damaged tissue.
This allows the stem-cell-stimulating drug to be carefully laid onto the brain (or spinal cord), safely getting around the blood barrier (or the blood-spinal-cord barrier), beyond which the drug is able to act to promote repair.
“If I knew how complex the central nervous system was, I wouldn’t have gotten into this field,” Shoichet jokes. “But it’s this complexity that makes my field so exhilarating and full of promise.”
Cancer research caught Shoichet’s attention after a good friend died of breast cancer ten years ago. Now, Shoichet and her team are creating materials that will deliver drugs directly to cancer cells, aiming to overcome some of the horrible side effects of current cancer treatments.
To do so, they deliver potent drugs to the centre of a cancerous area where the drugs disperse throughout the area and stay around long enough to kill cancer cells, leaving healthy cells largely untouched.
Riding inside the polymers that carry these drugs, nano-beads spread through cancer-stricken areas via the vascular system. At 1/1000 the thickness of a human hair, the beads are small enough to cross the leaky cancerous vasculature but large enough to stop at the more solid healthy vasculature.
Shoichet hopes these discoveries and many others her team is working on – such as microscopic scaffolding that guides where cells will grow tissues for transplantation – will soon help improve our quality of life.
When those real-world benefits come (some of Shoichet’s work has already been commercialized), she insists that it’s all been possible only through connections with hundreds of colleagues and students.
“Molly is a fantastic collaborator who never gives up on people or ideas,” says Dr. Cindi Morshead, colleague and Anatomy Chair at the U of T’s Donnelly Centre for Cellular & Biomolecular Research. “She just has such an incredible energy.”
In addition to the honour for Shoichet, U of T and Hospital for Sick Children postdoctoral researcher Vanessa D’Costa received one of this year’s 15 L’Oréal-UNESCO For Women in Science Rising Talent grants for her research into new drug-resistant strains of salmonella.
Reported by Peter McMahon, University of Toronto