Cat lovers may have more in common with their feline companions than they realize.
New research published in the journal Science suggests that cats and humans develop similar cancers due to genetic mutations that cause comparable tumors. This discovery could lead to new treatments for cancer in both pets and people.
Researchers created a “feline oncogenome”—a profile of genetic mutations in cats that can lead to malignant tumors—using samples from nearly 500 cats from Canada, the United Kingdom, Germany, Austria and New Zealand. The study analyzed thirteen distinct types of cancer in cats, looking for 1,000 genes known to cause the disease in humans. Understanding the genetic basis of cancer across species is a crucial step toward developing more effective therapies.
The oncogenome revealed that half of the cat cancer samples had a mutation in the FBXW7 gene, which is associated with aggressive forms of breast cancer in humans. Slightly less than half of the samples showed mutations in PIK3CA, also linked to human breast cancer. The most frequent mutation found in cats was in the TP53 gene, also known as p53, a key factor in many human cancers.
A Better Model for Cancer Treatment?
Whereas laboratory rodents have long been used to study cancer and potential drugs, cats may offer a more suitable model for scientific research. “Here we have a model of tumors that develop spontaneously, just like in humans,” says Louise van der Weyden, lead researcher of the study from the Wellcome Sanger Institute in the United Kingdom.
“These pets—cats and dogs—are in the same environment as us, so they are exposed to the same pollution […] something you don’t get in the laboratory.”
By utilizing a large number of non-pedigree domestic cats, researchers were able to study a genetically diverse group to identify common mutations in both cats and humans. Van der Weyden notes that the group could be expanded to include cats from other countries to provide an even broader understanding of the shared causes of cancer in felines and humans.
One area of particular interest is the potential for the feline oncogenome project to help identify environmental risks within the home. For example, if a specific genetic change triggers breast cancer in a family cat, it could indicate similar risks for people living in the same house.
“There are many studies that are already starting to consider cats and dogs as sentinels of the environment—like the canary in the coal mine—because they are in exactly the same environment as us,” explains van der Weyden. “We observe mutations due to ultraviolet radiation [in cats] that were exactly the same as in humans, for example.”
What’s Next for the Oncogenome?
In 2025, a team from the University of California in the United States began testing potential cancer therapies on cats, with possible benefits for humans as well. Led by Daniel Johnson and Jennifer Grandis, the team tested a drug used to treat squamous cell carcinomas in humans on a group of cats with an oral form of the disease. Approximately one-third of the treated cats lived, on average, six months longer.
Although they did not participate in the new oncogenome research, the University of California team welcomed the findings. “This is truly an exciting paper that further supports the relevance to humans, as well as to pets, of studies like ours,” Johnson and Grandis wrote via email.
“It is remarkable that alterations in genes like p53 are found with high prevalence in both humans and cats. People can now begin to use studies like this to develop personalized cancer therapies for both cats and people.”
Van der Weyden hopes her group can continue to research cancer in pets to benefit both animals and humans. Because using “real-world” animals minimizes harm compared to laboratory animals, and with owner support, unnecessary harm could also be avoided, she says.
“Most [owners] sign a form to authorize that [biopsy samples] be used for research purposes, which I suppose is very open and really wonderful,” says van der Weyden. “It would be fantastic if something positive came of it. I think it is important to acknowledge all the owners who do this, because without them, we could not carry out this type of study.”
(md/ms)
