The promise of stem cells

Regenerative medicine: It sounds like something straight out of science fiction, but you’ll be hearing a lot about this field of medicine in years to come. While you can’t see them without a microscope, tiny stem cells are likely to play a huge role in how we will treat illness and injury in the future — namely, how we can help the body heal itself.

It’s also a field that is moving forward at an incredible pace, and many of the innovations are happening at the McEwen Centre in Toronto.

“We’re pushing the barriers more and more,” says Dr. Gordon Keller, Director at the McEwen Centre for Regenerative Medicine and Senior Scientist, Division of Stem Cell and Developmental Biology with the Ontario Cancer Institute. “Stem cells are going to impact advances in medicine.”

Regenerative medicine isn’t just about regenerating and replacing damaged cells and tissues. We may not hear about them as often, but projects that focus on studying the origins of disease and those aimed at developing new tools for research are also key components. For example, stem cells can help researchers understand what causes disease — and how to create better treatments.

So what hope can regenerative medicine offer for the issues we worry about — like cancer, diabetes and heart disease? Here are a few highlights of work currently being done at the McEwen Centre.

Heart disease

Contrary to the cliché, time won’t heal a broken heart — but stem cells may be able to combat the damage caused by disease and defects. For example, current research at the McEwen Centre includes:

– Studying how heart cells divide, so future therapies can stimulate healthy heart cells to reproduce and replace lost or damaged tissue.

– Examining how stem cells develop into the different types of cells that make up the heart. In the future, this knowledge could be used to develop and provide cells for transplants and research.

“For the first time ever, we can create human heart cells in a dish and send them anywhere in the world for study,” reports Dr. Keller.

New drugs can be tested on the heart cells made from stem cells. This will enable pharmaceutical companies to determine if the new drugs are safe — saving time, effort and money in an expensive research and development cycle.

– Developing a “patch” or scaffold to repair and restore the heart and correct congenital heart defects. Doctors have even been able to create a “beating heart patch”. This progress, combined with research on how heart cells communicate with one another, could one day lead to new approaches to repair the damage caused by a heart attack.


Today, a diagnosis of type 1 diabetes usually means a lifetime of careful management and medication — but tomorrow, stem cell research could lead to better treatments or even a cure. Investigators at the McEwen Centre are studying how stem cells can be directed to become what are called pancreatic beta cells — that is, cells that sense glucose and produce insulin. These specially-developed cells can then be transplanted into patients with diabetes.

“In the past few years we have answered the question: Can we create pancreatic beta cells in the lab?” says Cheryl McEwen, co-founder of McEwen Centre. “Not only that, but today these cells secrete insulin in the lab environment. The new Harry Rosen Chair in Diabetes Stem Cell Research, made possible by public donations, will take this work to the next level. We foresee the day when the implantation of stem cell-derived beta cells in the body will be used to treat certain types of diabetes.”


Not all stem cell lines are destined for future transplants. McEwen researchers are carefully looking at “cancer stem cells” — the small population of cells in a tumour that could be behind the disease’s progression and reoccurrence — in order to develop treatments to target these rogue cells.

“There is lots of excitement in the area of modelling disease in a Petri dish and recreating the events that lead to cancer,” Dr. Keller notes. “When you identify the earliest changes that can lead to disease, you can identify targets for new therapies.”

Lung disease

Healthy lungs are vital for life — but donor organs are in short supply because many of them are rejected due to signs of inflammation or injury. However, stem cell therapies can literally “breath new life” into these organs.

“In just a few years, one of our investigators, Dr. Shaf Keshavjee, has made a dramatic difference in lung transplantation by rolling out his innovative approach to using gene therapy to repair human donor lungs,” reports Ms. McEwen. “This work has dramatically increased the number of lungs available for transplant. Since early 2009, dozens of seriously ill patients in Toronto have benefited from receiving the repaired lungs.”

Blood cell disorders

Many people forget that one stem cell therapy has been in use for decades: Bone marrow transplants. Today, McEwen investigators continue to examine how leukemia cells form and propagate — and how to identify and target these dangerous cells.

Of course, leukemia isn’t the only focus. Researchers are also looking at how different types of blood cells form and communicate as well as how blood vessels develop in normal versus pathological conditions.

Spinal cord injuries and neurodegenerative diseases

It was once thought that people with spinal cord injuries or neurodegenerative diseases like Alzheimer’s, ALS or Parkinson’s disease had no hope for a cure. After all, the spinal cord can’t repair itself, and the brain can’t replace those all-important neurons.

However, specialized stems cells may be able to fill in the gaps to restore function. For example, a developing a variety of strategies to treat neurodegenerative diseases or the damage done by a stroke.

Other investigators are working on ways to “bridge” lesions in the spinal cord with specially-developed stem cells, or to build scaffolding that will help heal spinal injuries or deliver stem cells and medications directly to the affected area.

(Want more information? Visit the McEwen Centre Research webpage for more details about ongoing research.)

What about the controversy?

It all sounds promising, but stem cell research has been dogged by controversy and misconceptions in the past. However, public perception is changing along with the science — and people are becoming more aware of the ethical standards in place.

“Our monitoring of both research and the media indicates that while there have been significant misconceptions regarding stem cell research and regenerative medicine, the level of controversy is actually decreasing,” says Ms. McEwen. “This may be in part due to increasing awareness by the public that in the future, much of this research may be performed using induced pluripotent stem cells, which are basically adult skin cells that are reverse engineered into stem cells. So, there is less concern regarding the source of stem cells used in research.”

In addition to adhering to tight ethical standards set out by research facilities and granting agencies, scientists (including the experts at the McEwen Centre) are now adopting the principles outlined in the Stem Cell Charter. The charter — which outlines principles covering responsibilities, protection from harm, intellectual freedom, transparency and integrity — was developed by the Canadian Stem Cell Foundation, a charitable organization established in 2008. (For more information, visit

Ultimately, successful treatments speak for themselves.

“When people realize that some types of stem cell therapy, such as those used to treat leukemia, are successful and in widespread use today, their perspective becomes still more positive,” explains Ms. McEwen.

More about the McEwen Centre

The McEwen Centre, part of the Toronto-based University Health Network, was established with the goal to become a world-renowned centre for stem cell biology and regenerative medicine. While it’s easy to be wowed by the research potential, it’s the people that make medical advancements possible — including the team of 15 world-class experts and the centre’s co-founders, Rob and Cheryl McEwen. The McEwens’ support helped establish the centre in 2003, and it’s a cause with a personal connection.

“A little less than 10 years ago, my husband Rob lost two members of his family to serious illness during the same year. Like many people who suffer deep personal loss, we wanted to make a difference,” says Ms. McEwen. “As we investigated giving opportunities, we were drawn to the innovative frontiers of science — the areas that would have the best chance to drive huge breakthroughs in the next 10 to 20 years.”

It isn’t just the McEwens’ generous gifts or government grants that make a difference. Ms. McEwen advocates that support from the public also plays a crucial role in stem cell research. Anyone can make a contribution to fund the research, or participate in the centre’s fundraising and educational events, like the recent Hats off to Harry event to honour Canadian icon Harry Rosen. (The McEwen Centre receives donations from around the world and issues tax receipts for US and Canadian donors.)Keep your eyes open for upcoming events including the 2nd Annual Day of Science in September, and the Gentle Ben Golf Classic Tournament this October.

For more information about the McEwen Centre, visit, and watch this introduction featuring Dr. Keller.

Photograph courtesy of the McEwen Centre