Dogs share many aspects of their lives with humans – such as loving a warm fire, a good dinner and regular belly rubs. But man's best friend also shares a darker trait with its owners – the ability to spontaneously develop cancer, which is the most common cause of doggy death. While the genomes of several breeds of dogs have now been sequenced, helping to shed light on many diseases that affect both humans and canines, less is known about the epigenome – the molecular switches that control when genes are turned on or off.
Writing in the journal Cancer Research this month, Spanish researchers have characterised the dog epigenome, in this case from the cocker spaniel, in unprecedented depth. They also found that when the dog cells undergo a change that is critical in the development of cancer, known as the epithelial to mesenchymal transition, there are key epigenetic changes. Importantly, similar changes are seen in human cells when they undergo this transformation, suggesting pathways that are conserved during evolution. Researchers around the world are currently developing drugs that can manipulate the epigenome, which may hold promise for treating cancer not only in ourselves, but in our four-legged friends too.