The research, published in Science, is the first large-scale effort to genetically profile cancers in cats. Researchers believe the findings could improve understanding of cancer in both animals and humans while also creating a valuable open resource for future feline cancer studies.

Cancer is one of the leading causes of disease and death in cats, yet scientists have historically known very little about the genetic changes driving these illnesses.

"Despite domestic cats being common pets, there was very little known about the genetics of cancer in these animals," said Dr. Geoffrey Wood, a professor of pathobiology at the University of Guelph and co-senior author of the study, "until now."

Cat Tumors Show Strong Genetic Similarities to Human Cancers

Researchers analyzed tumor samples from nearly 500 domestic cats collected across five countries. The team investigated the genetic mutations involved in cancer development and discovered many of the same cancer-driving genes seen in human and dog cancers.

Among the most important findings were mutations linked to aggressive mammary cancers in cats.

The gene most frequently altered in feline mammary tumors was FBXW7, with mutations appearing in more than half of the tumors studied.

In human breast cancer, mutations in FBXW7 are associated with poorer outcomes, closely matching what researchers observed in cats.

Scientists also identified similarities between feline and human cancers affecting the blood, bones, lungs, skin, gastrointestinal tract, and central nervous system.

Because cats often share the same environments as their owners, researchers believe some cancer risks could stem from common environmental exposures.

"This study 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," Wood said.

Chemotherapy Discovery Raises Hope for Future Treatments

Researchers were especially encouraged to find that certain chemotherapy drugs appeared to work better in cat mammary tumors carrying the mutated FBXW7 gene.

Although the results were observed only in tissue samples, scientists say the discovery could point toward new treatment possibilities for breast cancer in both animals and humans.

"Having access to such a large set of donated tissues allowed us to assess drug responses across tumor types," said Dr. Sven Rottenberg, co-senior author at the University of Bern, "in a way that hasn't been possible at this scale before."

Bailey Francis, co-first author at the Wellcome Sanger Institute, said the research may also provide benefits for dogs.

"When knowledge and data flows between different disciplines, we can all benefit."

"One Medicine" Approach Connects Human and Animal Health

The international project brought together researchers from the Wellcome Sanger Institute, the Ontario Veterinary College at the University of Guelph, the University of Bern, and several additional institutions.

Scientists sequenced DNA from tissue samples that veterinarians had previously collected for diagnostic purposes.

The findings suggest treatments already used in humans could eventually be tested in cats. At the same time, information gained through cancer trials involving domestic cats could help guide future human clinical research.

This collaborative strategy is known as the One Medicine approach, which encourages the exchange of knowledge between veterinary and medical researchers to improve health outcomes across species.

Dr. Louise Van Der Weyden, senior author at the Wellcome Sanger Institute, said the study opens the door for future advances in feline cancer care.

"We can now begin to take the next steps forwards 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."

The research received funding support from EveryCat Health Foundation, the CVS Group, Wellcome, the Natural Sciences and Engineering Research Council of Canada, and the Swiss National Science Foundation.