For centuries, dogs were important to humans as both companions and staff. Today, the hunt for a cure for brain cancer could be critical.
One common form of brain cancer is diffuse gliomas. They form within the central nervous system, which affect the brain’s glial cells.
These tumors are notoriously difficult for doctors to treat, and survival rates are low, with only 5 percent of people surviving 5 years or more.
Knowledge of these cancers is clearly gaping. Scientists do not understand their molecular biology or the development of the glial cells to malignance.
Dogs and cancer
Dogs have played an important role in the development of human society, and remain as close to humans as ever in modern times.
But dogs are as vulnerable as humans to developing gliomas.
Previous research has shown that these cancers are often acquired by adult dogs at around the same age in human years as children, indicating a correlation between brain age and glioma development could exist.
Studies of diffuse gliomas have hitherto focused on models of mouse in vivo. Nevertheless, the developmental pathology of glioma in the brain of a mouse is very different from that in the brain of a human or dog.
There are many parallels between human and dog glioma pathology, suggesting dogs could provide the best model yet to help scientists understand these cancer types.
At Jackson Laboratories in Maine, Prof. Roel Verhaak has found that gliomas in dogs may help scientists understand the complex pathology of diffuse gliomas better.
The team also reported results in Cancer Cell.
Brain tumors in dogs similar to humans
The team sought to determine whether glioma tumors in dogs and humans formed in the same way.
So, we analyzed the molecular signatures of 83 posthumous dog glioma samples and compared them with adult and child human biopsies.
To get this information, the team employed a wide variety of molecular sequencing technologies. We found that both humans and dogs shared mutations in genes which belong to well-known pathways of the cell cycle.
We found that the human and canine samples displayed many mutations. For the first time, this indicated that dogs and humans grow equally such forms of tumours.
The researchers also noted that the gliomas in dogs were more like gliomas in children than they were in humans, and found that the mutations occurred in canines as well as children at similar times of life.
For example, samples of adult tumors harbored mutations in the IDH1 gene, but these occurred only at a low rate in pediatric and canine samples.
Researchers have also found other differences between dog and child tumor samples. These included variations in chromosome numbers.
Eventually, the team found that improvements in the immune system were identical between human and canine samples in the tissue surrounding the tumors.
Treating dogs to help people
The researchers believe that the use of existing therapies to cure glioma in dogs can lead to advances in the care of the human condition.
Using immunotherapy on dogs will allow researchers to find ways to make it more humanly effective.
These findings may help scientists understand the relationship that occurs between other human cancers and dogs. That, in effect, could lead to better treatment developed for both species.
If the knowledge from this new study contributes to cancer research and treatment improvements, dogs may really be a best friend of a human.