Behind the science of cancer-fighting immunotherapy

Cancer affects hundreds of thousands of Canadians every year. Many patients are treated using the three pillars of cancer care: surgery, radiation and chemotherapy – treatments that often come with risks and often debilitating side effects.

READ MORE: ‘This is it’: the cancer treatment that has doctors talking about a cure

Now scientists and researchers are working to develop ways to harness the power of the body’s immune system to fight cancer. The treatment is called immunotherapy. Doctors are enthusiastic about some of the results they are seeing.

Here’s why, in their own words, experts believe the immune system is key to killing cancer.

WATCH BELOW: Dr. Pamela Ohashi is the director of the tumor immunotherapy program at Princess Margaret Cancer Centre in Toronto. She explains the role T-cells play in the fight against cancer

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16×9: How much does technology play a part in advancing this type of treatment?

Dr. Pamela Ohashi: The role of technology has a critical place in advancing different types of immunotherapy. The ones that we have been working on right now, where we grow patients’ tumour-fighting t-cells directly from the tumour, has often thought to be not something that can be achieved on a mass production level. Recently, because new approaches have proven very, very successful in different kinds of blood tumours, industry has taken on the challenge to figure out how to get the cell therapy, how to get this very, very personalized medicine to patients in the clinic.

WATCH BELOW: Dr. John Bell is a senior scientist at the Ottawa Hospital Research Institute in Ottawa. He is discussing the science behind oncolytic virus therapy and why cancer cells are so vulnerable to virus

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16×9: Before you inject the virus into a patient, do you have to modify it in any way so that it doesn’t spread or infect the person receiving the treatment?

Dr. John Bell: Absolutely. We do a lot of what we call genetic engineering and what we do is, understanding virus biology and understanding cancer biology. We tailor the virus so they can only infect the cancer cell.

READ MORE: Viruses that can destroy cancer? Canadians leading the way in new research

We actually debilitate it so when it enters a normal cell it’s really ineffective. It becomes like a vaccine in that it has no impact on normal tissue. But when it enters a cancer cell which has gotten rid of this, and evolved programs, then the virus can grow quite well there. So it’s sort of like throwing the seeds on the ground and if they land on the pavement which would be the normal cells which can’t grow, if they land on the dirt where the tumour is, they grow quite well.

WATCH BELOW: Dr. Marcus Butler is a medical oncologist and director of the immune monitoring lab at the Princess Margaret Cancer Centre in Toronto. He is discussing the successes of immunotherapy

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16×9: Why is this area of treatment (immunotherapy) so promising?

Dr. Marcus Butler: Well, first of all, it’s a new area that’s showing a lot of clinical benefit in the last few years. It is not a new area from the standpoint of science. People have been working on immune therapy since the late 1800s, but in the last 20 years some very important basic understanding of the way the immune system works has been discovered, and that’s resulted in new therapies and new treatments that have come to the clinic that are making an impact on patients.