All types of cancers seen in humans also show up in dogs. For example, take breast cancer: Like women, female dogs (those not neutered, or are at a breeder) also come down with breast cancer, generally called mammary cancer in dogs.
Further, not only the biology of cancer is similar in dogs and man, the dogs also respond to same cancer drugs that are used for humans.
On March 31st, 2014, The New York Times profiled the Penn Vet Shelter Canine Mammary Tumor Program on its website. This innovative program, run by Dr Karin Sorenimo, the Professor of Oncology at the University of Pennsylvania, takes in shelter dogs for cancer treatment and care; the dogs in turn help advance research into the biology of cancer by ways that are impossible to do in humans.
(From nytimes.com, March 31, 2014)
By comparing the molecular profile of these breast cancer tumors which are at various stages of development, but all with same genetic background, researchers can ask specific questions, such as:
- What are the switches (or signaling pathway changes) that occur when cancer advances from benign to malignant stage
- What are the specific biomarkers for various stages of cancer
- Can those biomarkers be used for targeted therapies in clinic (for humans) or in development
- Or, can these biomarkers be used to try out therapies in dogs first before going to humans
NIH-NCI Comparative Oncology Program
Ten years ago, in 2003, the National Cancer Institute's Center of for Cancer Research (CCR) launched the Comparative Oncology Program (COP).
The purpose of this program was:
- to understand the biology of cancer
- to promote clinical research on novel therapies for humans by treating pets (dogs and cats) with naturally-occurring cancers, and
- to bring innovative therapies to veterinary care
The clinical trials sponsored by the NCI's comparative oncology program are listed here.
Why so much much effort and tax-payer dollars have gone into comparative oncology program can be summed up by Dr Chand Khanna's statement to New York Times: “Every cancer that develops in a dog develops in a human, and for the most part, the reverse is true as well.”
Therefore, what we learn by treating man's best friend can ultimately help humans themselves.
Dr. Chand Khanna developed the comparative oncology program at the National Cancer Institute’s Center for Cancer Research.
Different breeds of dogs are predisposed to different types of cancers. For example, Belgian shepherd are more likely to get gastric carcinoma, whereas prostate cancers are more common in Doberman pinscher. One of the reasons for high rate of cancer and predispositon to certain cancer type in different dog breeds is the loss of genetic diversity in these breeds.
The domestication of wild wolves and breeding of specific dog breeds while helping man create beautiful and prized canine friends, has also led to a loss of up to 35% of genetic diversity in pet dogs compared to their ancestors, the wild wolves.
Nonetheless, the molecular analysis of tumors from these dog breeds has created an opportunity for researchers to investigate signaling pathways involved in tumor progression by providing multiple samples often from the same animal.
Dr Olga Troyanskaya, the Professor of bioinformatics at Princeton, is collaborating with Dr Sorenimo of UPenn, the chief oncologist of the shelter dog cancer program (Penn Vet mammary tumor program) to delineate cancer pathways in breast cancer.
Below are the similarities between dog and human breast cancer pathways (Source: Dobson JM. ISRN Veterinary Science, 2013, Article ID 941275)
|Human breast cancer||Canine mammary tumor|
|Gene sets/signaling pathways|
Beyond Breast Cancer
About 12 million American homes experience the anguish of their pets coming down with cancer every year, that's 6 million dogs and similar number of cats. These four-legged companions come down with all kinds of cancers as in humans. By promoting the research and cancer drug development for dogs, the NIH and other programs help both the pet owners as well as help understand human cancer.
- From Dogs, Answers About Breast Cancer. By Roni Caryn Rabin. New York Times. March 31, 2014. Available at: http://well.blogs.nytimes.com/2014/03/31/by-treating-dogs-helping-humans/ (In print: By Treating Dogs, Helping Humans. By Roni Caryn Rabin, New York Times, New York edition. April 1, 2014. Page D6)
- Common Mutations Drive 12 Different Cancer Types. October 20, 2013.
- 1000 Genomes, Clan Genomics and Cancer Biomarkers. September 30, 2011.
- Oncology Focused Pharmacogenomic "Predictive" Biomarkers. February 6, 2011.
- Friday Grand Rounds: Harold Varmus Discusses Cancer Cell Biology and Clinical Translation. February 11, 2011.
- Posts on Cancer Mechanisms." http://www.missiontumor.com/search/label/cancer%20moa
- Posts on Breast Cancer. http://www.missiontumor.com/search/label/breast%20cancer
Paoloni M, Webb C, Mazcko C, Cherba D, Hendricks W, Lana S, Ehrhart EJ, Charles B, Fehling H, Kumar L, Vail D, Henson M, Childress M, Kitchell B, Kingsley C, Kim S, Neff M, Davis B, Khanna C, & Trent J (2014). Prospective Molecular Profiling of Canine Cancers Provides a Clinically Relevant Comparative Model for Evaluating Personalized Medicine (PMed) Trials. PloS One, 9 (3) PMID: 24637659
Dobson JM (2013). Breed-predispositions to cancer in pedigree dogs. ISRN Veterinary Science, 2013 PMID: 23738139