A natural killer of cancer cells

20 September 2017

The immune system is the body’s natural defense mechanism against foreign and potentially harmful cells and organisms. A natural killer (NK) cell is a type of immune cell that patrols the body for unhealthy cells, including cancer cells. Once they detect cancer cells, NK cells often become activated to kill them directly or alert other immune cells to mount an immune attack. Because of these functions, NK cells are an important focus for immunotherapy research.

With the help of donors’ support, the Canadian Cancer Society proudly awards grants to world-renowned researchers who are leading cutting-edge cancer research. Valued together at more than $740,000, 3 ongoing grants are supporting researchers who are using NK cells for the treatment and prevention of cancer.
Understanding immune evasion
Some cancers, including those of the breast and blood, can avoid or evade immune detection by NK cells, resulting in the growth and survival of tumours. At the University of Ottawa, Dr Andrew Makrigiannis and his team suspect that these tumours can lack specific proteins that normally allow NK cells to recognize them. Using animal models and computer analyses, the team hopes to learn more about these proteins and their relationship with breast and blood cancers. They will also combine NK-enhancing drugs with other chemotherapy drugs to improve therapeutic outcomes. The researchers hope to bring a new NK cell-based immunotherapy to clinical trials.
Boosting NK cells by starving tumour cells
Part of an effective immune response is making sure immune cells have enough nutrients, like the sugar glucose, to survive. However, tumour cells can divide quickly and take up all the glucose in their environment, supporting their growth and starving immune cells. Some studies have proposed that fasting (abstaining from food and drink) may help prevent and treat cancer because there may be less glucose available for tumour cells to consume. Under low-glucose conditions, Dr Seung-Hwan Lee and his colleagues at the University of Ottawa discovered that NK cells can consume a different molecule to survive, one that does not support tumour cell survival. By placing animals with cancer on a special diet and treatment plan, the team hopes to boost NK cell survival in these animals, which could improve the immune response and stop the tumour from growing. This research could potentially translate into a simple but effective treatment and prevention strategy for a variety of cancers.
A new hand-selected therapy for pancreatic cancer
Cancer can be difficult to treat because each tumour is unique, as is the ability of each person’s unique immune system to fight it; even NK cells vary in how effectively they can kill tumour cells. For aggressive cancers like pancreatic cancer, perhaps selecting the most potent NK cells can successfully eliminate the tumour. With this in mind, Dr Jeanette Boudreau and her team from Dalhousie University are studying if selecting specific NK cells to kill pancreatic cancer is an effective treatment strategy. In the future, this could lead to a computer program that can choose the best NK cells to kill a particular person’s pancreatic cancer.

Exploiting NK cells in the immune system is an emerging area in cancer research, and our researchers are helping to lead the way. Thanks to our generous donors, the Canadian Cancer Society is investing over $2.6 million towards cancer immunotherapy research so far this year. With your support, we hope to bring the goal of beating cancer closer to reality.

Learn more about the impact of our research.

The writing of this story/article was supported by a BioCanRx research communications internship.