Reciprocal Relationship of PTEN and p21 in Canine Cancer

An estimated one out of every two dogs alive today will get cancer in its lifetime, and as many as 50 percent of those will die from the disease. Despite significant gains in cancer treatment, a thorough understanding of why cancers arise and why they behave as they do is essential to improving prevention and treatment. For this project, researchers will investigate two proteins whose interactions appear to be intimately tied to the behavior of two serious cancers, melanoma and hemangiosarcoma. What they learn may help to test targeted therapies for these cancers and significantly improve the lives of affected dogs.


Cancer is the leading cause of disease-related death in dogs, which is why the Morris Animal Foundation and the Portuguese Water Dog Foundation have invested considerable resources to understand this group of diseases to develop more effective treatments. Cancer happens when genes that control the balance of division and survival cease to function normally in a cell and cause it to become malignant. One of these genes is called PTEN. The protein product of this gene generally restrains cell division, in part by controlling another protein called p21.

Scientists at the University of Minnesota and at the University of California, Davis have found that using compounds to lower the levels of p21 in some tumors decreased the resistance to conventional chemotherapy drugs. They also concluded that chemotherapy resistance is sometimes unrelated to abnormalities of PTEN, while it is often associated with elevations of p21. The results have allowed the investigators to justify efforts to move these compounds to the next step of clinical development.

Co-sponsored with the Morris Animal Foundation, Grant Number: D06CA-065


Jaime F. Modiano, VMD, PhD
University of Minnesota