Pets can change cancer care for humans
Our animal companions bring us joy and love us unconditionally. But what might surprise people is that our pets may hold the key to a cure for human diseases, including cancer.
Cancer is one of the leading causes of death worldwide, killing 230 Canadians each day. Traditionally, when a researcher develops a cancer therapy, it is first tested in lab-grown cancer cells to determine whether the treatment will have any effects against the tumour.
Next, the therapy is tested on mice by artificially inducing the disease and assessing the ability of the therapy to kill the cancer. If the therapy appears to work, it is then taken to human patients in an initial safety and efficacy trial.
We are becoming acutely aware that this approach is flawed. A staggering 94 per cent of cancer therapies developed using mice fail to show any clinical benefit in people.
Additionally, taking just one experimental therapy to clinical trials in people can cost millions of dollars.
The Ontario Veterinary College at the University of Guelph is home to a very busy Animal Cancer Centre that treats more than 5,000 companion animals for cancer annually. In contrast to lab rodents, companion animals like dogs and cats develop cancer spontaneously, just like humans. And they live in the same environment we do and are faced with the same environmental pressures.
Tumours from companion animals similar genetic diversity to those seen in humans in contrast to the genetic homogeneity seen in mice. Our pets are almost perfect models to test disease treatments.
Our research team treats pets with conventional and cuttingedge cancer therapies. These include anti-cancer viruses, therapies to restrict blood flow to tumours and treatments to activate the immune system.
We are now partnering with clinicians that treat people with cancer. With these partnerships, we can take a therapy from testing in cancer cells and mice to companion animal cancer trials, and ultimately to humans. This is known as translational research.
With translational research, we can identify and discontinue therapies that are unlikely to have a clinical benefit. This could dramatically reduce the high failure rate we are currently seeing in cancer therapies tested in people. For therapies that show promise, we can revise, refine and improve the therapeutic approach, both in the companion animal trials, and in preclinical rodent models.
Revised therapies can be further tested in companion animal trials, and then moved to human clinical trials.
A translational approach with companion animal models represents a shift in how we develop cancer therapies and provides an exciting opportunity to develop effective therapies in both people and pets.
And the promise of this approach extends beyond cancer to other conditions.
There are several other medical conditions that show a similarity of causes between humans and companion animals, such as osteoarthritis of the knee and hip and some psychiatric conditions such as obsessive-compulsive disorder.
From the kennel to a cure, translational research will change the landscape of disease therapy in Canada and could dramatically improve the lives of Canadians and their pets.
• Jim Petrik is professor of biomedical sciences
• Lauren Grant is assistant professor of environmental and public health
• Michelle Oblak is associate professor of soft tissue and oncologic surgery
• Shayan Sharif is professor of immunology and associate dean for research and graduate studies at the University of Guelph.