They are called "natural killer cells" for a reason and Ottawa researchers are working to enhance the body's own use of these cells to kill cancer.

Immunotherapy is revolutionizing our approach to cancer treatment but so far, success has been limited to certain types of cancer.  The hope is that the research into these "natural killer" cells could unlock a mystery as to why immunotherapy has worked in only certain kinds of cancer.  Ultimately, the hope is to gear cancer treatment based around on a person's own immune system.

As a professor of Economics, Dr. David Gray is used to working with numbers, so he knew the stats on his survival rate were grim.

“I was given a probability of zero point three, zero point three five,” says Gray, “which was 1 in 3 perhaps of reaching the 5 year survival rate.”

That was March of 2013, more than five years ago.  Gray was diagnosed with a deadly melanoma in his cheek.

The traditional treatment regime didn't improve those odds much.  But timing is everything. Gray happened to qualify for a trial using his own immune cells to kill off the cancer. 

“A year or two before” says Gray, “and it's quite possible I wouldn't be standing here today.”

Immunotherapy is revolutionizing the treatment of cancer, waking up the body's own immune system to attack cancer cells.   The focus has been on what's called anti-tumor T cells but researchers at the Ottawa Hospital Research Institute are examining how to unleash the power of what's called "natural killer" cells, our body’s own white blood cells,  to target cancers that "T" cells haven't been able to.

The tough part is trying to figure out how to activate or "turn on" these cells.

Dr. Michele Ardolino  is a tumor immunologist at the Ottawa Hospital and an assistant professor at the University of Ottawa.

“In patients with cancer, they (the Natural Killer cells) are often in an inactivated state and we don't really know the mechanisms that regulate the inactivation but we are finding more about this while the study progresses.”

Dr. Ardolino is leading a study into these often-overlooked immune cells with Dr. David Raulet, a professor at the University of California at Berkeley. The research was published in the prestigious Journal of Clinical Investigation.

The aim, explains Dr. Ardolino, is eventually to tailor an immunotherapy treatment based on each individual patient.

“Every tumor is different,” he says, “and if we can personalize a treatment to the patient level, then immunotherapy will be way more effective.”

Professor Gray has been cancer free for 5 years.  He beat incredible odds and hopes the numbers remain in his favor.

“The last time I had bad news,” says Gray, “was with the awful pathology report back in the spring of 2013.  So after being very unlucky, I've been lucky ever since.”

There has been a lot of really interesting research around immunotherapy coming out of the Ottawa Hospital and the Ottawa Hospital Research Institute, considered a leader in this field.