Figure 1

The PennVet Shelter Mammary Tumor Program was founded to save homeless dogs with mammary tumors while at the same time advance clinical and translational research on breast cancer. Our studies have enabled us to 1) develop a more accurate and personalized prognostication system for dogs with mammary tumors, 2) undertake a comparative analysis of the molecular changes associated with breast carcinogenesis in canines and humans, and 3) evaluate changes in the tumor microenvironment (TME) associated with malignant transformation and poor outcomes. Understanding the global and diverse effect of estrogen has become a central theme in this work; it influences the biological behavior of the tumors due to its carcinogenic and anticarcinogenic effects, as well as modulating the TME. Recently, we have shown that high serum estrogen levels are associated with formation of a tumor-restrictive tumor stroma. This finding complements our previous work that identified both tumor-restrictive and -permissive collagen signatures that regulate biochemical, biophysical and biomechanical signaling in the tumor microenvironment. Collectively, this collaborative program aims to improve the clinical care of both canine and human breast cancer patients by unraveling the complex and dynamic relationship between tumor, tumor microenvironment and hormonal factors.

About Dr. Sorenmo: Karin Sorenmo, DACVIM (Oncology), DECVIM (Oncology) is an Emeritus Professor of Oncology, School of Veterinary Medicine at the University of Pennsylvania, and Cofounder and Chief Medical Director of Lesley’s Place, a non-profit foundation caring for homeless dogs with mammary tumors. Her research interests and publications span across a relatively wide range of cancers, both in dogs and cats. Mammary tumors or breast cancer, however, has always been her main research interest and publications within this area represent her most significant part of her scientific contribution to the literature.

About Dr. Volk: Susan Volk VMD, PhD, DACVS is an Associate Professor of Small Animal Surgery at the University of Pennsylvania School of Veterinary Medicine. Her laboratory is focused on developing innovative strategies through basic science discoveries which close clinical gaps in patient care, particularly when “the scalpel doesn’t cut it.” She has developed a research program focused on understanding dynamic reciprocity between cells and their surrounding extracellular matrix in both regenerative and tumor microenvironments.