COLUMBIA – Sometimes, Jeffrey Bryan treats sick dogs whose owners have had their own painful experiences with cancer.
Survivors bring their pets to see him hoping the dogs, too, will be cancer survivors.
Bryan said he sees cases where those who have lost family members to cancer are unwilling to give up on their pets.
"One of my favorite things is to be able to keep people and their dogs together," said Bryan, 46, an associate professor of oncology with the Veterinary Medical Teaching Hospital.
These stories have been a motivation for Bryan to continue his research on cancer in animals.
Bryan was the first to discover Y chromosome DNA in the blood of female dogs. This was surprising, he said, because, in fact, a female should not have the Y chromosome.
His research has found that one-third of female golden retrievers carry male cells in their bodies. The females picked up the cells from their babies during pregnancy. This occurrence has also been found in dachshunds and mixed-breed dogs.
"When I first heard about it, it was just a mind-blowing thing," Bryan said. "It never occurred to me that more than one person would live inside another person."
Scientifically, this is known as fetal microchimerism, the persistence of fetal cells in the mother's body for years after pregnancy.
He said the cells can contribute to autoimmune diseases and some cancers, and they can also be useful in preventing cancer. He is using his results to develop treatment options.
As an illustration, he described a mother diagnosed with lymphoma, a type of blood cancer. If she has cells from her son in her body, those cells could be infused into her blood to provoke an immune response against the cancer.
"I think the dog's immune system is ideal for testing this strategy to see if this would work in treating cancer," Bryan said.
He is a graduate of the University of California, Davis, School of Veterinary Medicine. He spent nine years in general veterinary practice in San Francisco before coming to MU in 2002 for a residency in medical oncology.
Bryan earned his master of science in biomedical sciences and a doctorate in pathobiology at MU. In the teaching hospital, his focus is on comparative oncology.
"Of everything I did in practice, treating cancer patients is the most rewarding thing." he said.