Scientists have just discovered similarities between feline mammary cancers and human breast cancers that could possibly lead to a cure for both.
Despite cancer being one of the leading causes of illness and death in cats, very little was known about its genetics, until now.
In their study, experts at the Wellcome Sanger Institute, the Ontario Veterinary College in Canada, the University of Bern, and their collaborators have identified genetic changes that could help treat the condition not only in cats but in humans too.
The researchers analyzed almost 500 pet cats across five countries to compare the genetic changes to those seen in humans.
By sequencing DNA from tissue samples that had already been collected by their veterinarians for diagnostic purposes, the team found that, for some types, the genetic changes that drive cancer development in domestic cats are comparable to those observed in humans.
"Our household pets share the same spaces as us, meaning that they are also exposed to the same environmental factors that we are," paper author professor Geoffrey Wood of the Ontario Veterinary College, Canada said in a statement.
"This can help us understand more about why cancer develops in cats and humans, how the world around us influences cancer risk, and possibly find new ways to prevent and treat it."
In the new study, the first to genetically profile cat cancer tumors at scale, researchers looked for around 1,000 human cancer-associated genes in both tumors and healthy tissue samples -- including 13 different types of cat cancer -- to then compare the genetic changes to those seen in human and dog cancers.
"By comparing cancer genomics across different species, we gain a greater understanding of what causes cancer. One of our major findings was that the genetic changes in cat cancer are similar to some that are seen in humans and dogs," said paper author Bailey Francis of the Wellcome Sanger Institute in a statement.
The study identified seven driver genes which mutations led to the development of cancer. The most common driver gene was FBXW7; over 50 percent of the cat tumors had a change in this gene. In humans, changes in the FBXW7 gene in breast cancer tumors are associated with worse prognosis.
Another major finding of this study was that certain chemotherapy drugs were more effective in the cat mammary tumors with changes in the FBXW7 gene.
While this research was conducted in tissue samples only, which means it still requires further investigation, it may offer a potential avenue to cure both cats with mammary carcinoma and human breast cancer patients.
The second most common driver gene identified in the study was PIK3CA, seen in 47 percent of cat mammary carcinoma tumors—a genetic change that is also found in human breast cancer, where it is treated with PI3K inhibitors.
Other similarities to human driver mutations were seen across blood, bone, lung, skin, gastrointestinal and central nervous system tumors.
The researchers now suggest that successful therapeutic approaches in humans could then be trialed in cats. This is known as the "One Medicine" approach, which promotes the two-way flow of data and knowledge between medical and veterinary disciplines to benefit both human and animal health.
Dr Louise Van Der Weyden, senior author at the Wellcome Sanger Institute, said: "This is one of the biggest ever developments in feline oncology and means the genetics of domestic cat tumors are no longer a 'black box'.
"We can now begin to take the next steps forward towards precision feline oncology, to catch up with the diagnostic and therapeutic options that are available for dogs with cancer, and ultimately one day, humans."