Ruminations

Dog-Human Symbiosis

"To me, it's one medicine. It always has been. One medicine. One cancer. One cure."
"Convincing big drug companies that we have relevant models that can be studied so much cheaper than human trials [has been a difficult sell]."
"[Also at risk is that] on rare occasions cats don't behave like people], so research continued to focus on mice and rats as laboratory models."
Stephen Withrow, veterinarian, Flint Animal Cancer Center, Colorado State University

"[Dogs with cancer are treated as compassionately] sometimes even nicer [than people]. Nobody is taking a dog and putting him in a kennel in a room somewhere, never to be seen again, and experimenting on them. These are pets that are getting genuine care."
"One of the fundamental challenges facing us in human oncology is the fact that we are learning so much more about cancer -- the structure of cancer cells and how they behave."
"By including our pets in clinical trials, we might get some very valuable clues."
Dr. Len Lichtenfeld, deputy chief medical officer, American Cancer Society

"These people who are looking for breakthroughs aren't interested in whether the breakthrough comes from a dog or a zebra fish."
"Just give us something we can work with that will help speed up the process of drug development, which is so long and expensive."
Dr. Larry Glickman, professor emeritus, Purdue University

James Bareham

The theory seems to be that many of the life-threatening diseases that afflict humans present in dogs and likely cats in the very same way. Biologists look at a co-dependency and shared development in the relationship that began an estimated 30,000 years ago between humans and what we now regard as intimate companion animals in their mutual exposure to the same environment, quality of air and water and even food consumption affecting our genetic inheritance.

And that when nature patterned animals, humans were merely one species among many. That the basic design is not that much different between rats, pigs, dogs, monkeys and humans. So that when one is afflicted with a potentially lethal disease, its type and the journey it takes in the body in attacking vital organs, challenging the immune system and ultimately wreaking its destined devastation is strikingly similar.

Treat the symptoms and the presence of the interloper or demented cells in one member of the species and you may have gained the formula for treatment -- or a version of treatment -- in the others as well. When our loved and valued companion pets become seriously ill, most of us would do just about anything to ease their discomfort and if we have the wherewithal and the opportunity, plan for professional intervention to bring them back to health.

In the development of tumours there is an identifiable and real commonality between humans and dogs; biopsy studies often find difficulty in differentiating between human and dog. So too is the cardiovascular systems of both dogs and people very similar, according to veterinarians. The second most common form of heart disease in dogs, dilated cardiomyopathy -- a deadly disease -- also represents the third most common in humans.

There has developed a link in research, services and findings between veterinarian colleges and medical establishments. Where even myoclonic epilepsy, one of the most common forms presenting in children and adults also afflicts dogs. By treating such conditions in dogs, a learning process has been brought to the table, with results that are completely applicable to human patients.

Bridgett vonHoldt, an assistant professor in ecology and evolutionary biology at Princeton University, cuddles with her Old English sheepdog, Marla. VonHoldt and her fellow researchers found two gene variations that seem to explain doggy friendliness. (Chris Fascenelli/Princeton University)

The first full genome of a dog was mapped in 2005, when it was discovered that humans share more of their ancestral DNA with dogs than they do with mice, yet it has mostly been those tiny rodents that much biological research has focused on. When speaking 'research' and living animal models, most people would wince at the most uncomfortable thought that dogs would be used as laboratory models. On the other hand, these are peoples' beloved pets suffering from end-stage disease.

Canine cancer treatments run between $10,000 to $20,000, a steep dollar figure that most people would blanch at. Now that veterinarians are collaborating with human medicine researchers studying the genetics of for example, fatal heart disorder both dogs and humans share -- along with epilepsy and stem-cell therapy for spinal cord injuries -- research and treatment have gone hand-in-hand focusing on dog laboratory models.

Studies point out that cancer drugs in particular that appear to give promise when tested on lab rodents, fail the test of efficacy when moved into human trials. The co-evolution of dogs and humans, though, make it far more likely that what proves successful as a treatment for dogs can be transferred with a greater degree of success to humans, given our long exposure to the same pollutants and pathogens capable of triggering mutant cells into cancer.

Not that dogs haven't up to the present been used in vital research meant to benefit humans. The point of the current thinking is that in helping dogs overcome massive health assaults, humans will also benefit, given our similarities in organ function and body design. Back in 1921 at labs at the University of Toronto, Drs. Banting and Best's experiments were carried out on dogs. But those dogs underwent a procedure that afflicted them deliberately with diabetes.

The discovery that Dr. Banting was later co-awarded the Nobel Prize for Medicine for, in isolating insulin and injecting it into a laboratory test dog did save its life, but it was the experiment that placed the dog in peril to begin with, in deliberately isolating the hormone in dogs. This new approach with dog models in the link between veterinarian services and human health research comes at a different angle, working to improve the health of dogs afflicted with disease, a process that benefits humankind.