Tag Archives: cancer

Elevated cholesterol’s link with canine osteosarcoma includes a better prognosis

Note from Doggy Mom:  I follow lots of areas of research in the canine field, but anything to do with osteosarcoma is interesting to me since greyhounds are known for suffering from this type of cancer.  Izzy is a greyhound!


Usually thought of as a health detriment, elevated cholesterol may play a role in longer survival times for dogs with a common form of bone cancer.

In addition to their veterinary significance, the findings by Oregon State University researchers advance the understanding of a type of malignant tumor, osteosarcoma, that’s often diagnosed in humans as well, typically afflicting teenagers and young adults.

Dog with cancer

A dog with osteosarcoma; Photo courtesy of Oregon State University

“This is one of the first steps into identifying cholesterol as a potential biomarker for canine osteosarcoma,” said Haley Leeper, a veterinary oncology resident at the OSU College of Veterinary Medicine. “We don’t have answers as to why high cholesterol is associated with this disease and with a better prognosis, but we’re hoping to advance these findings in future research.”

Leeper and collaborators at OSU and Iowa State University compared 64 dogs with osteosarcoma against two control groups: 30 dogs that had suffered traumatic bone fractures and 31 healthy dogs similar in age and weight to the animals with cancer.

Researchers found nearly half of the dogs with cancer – 29 of the 64 – had elevated levels of total serum cholesterol, a dramatically higher rate than occurred in either control population; just three of the 30 dogs with broken bones, and only two of the 31 healthy animals, showed high cholesterol.

Of the dogs stricken with osteosarcoma, 35 had the cancer in a leg which was subsequently amputated, followed by chemotherapy, which is the standard-of-care treatment; the dogs with elevated total cholesterol had a median survival time of 455 days, more than 200 days greater than the median survival time  for dogs with normal cholesterol.

“When people think of cholesterol they think of cheeseburgers and heart attacks,” Leeper said. “However, cholesterol is involved with many key processes and structures in the body like cell membranes, bone health and the immune system.”

Future studies that follow dogs long term and look at specific lipid content in the blood may shed light on the mechanisms behind cholesterol’s role in enhanced survival, Leeper said.

“There are a lot of things we plan on investigating,” she said. “This is exciting and fascinating, partly due to the comparative medical aspects between human research and our research.”

Source:  Oregon State University media release

Dogs help in breast cancer research

Cancer is one of the most frequent diseases not only in people, but in pets as well. Like people, dogs can also suffer from cancer of the mammary glands (mammary tumors). Dog mammary tumors are very similar to breast carcinoma in humans, and much more so than those of rats or mice, for example. For this reason, research on canine mammary tumors is important for human medicine as well. A study performed at the University of Zurich has now shown how similar mammary tumors are in both people and dogs.

Enni Markkanen, Vetsuisse-Fakultät Zürich, Untersuch Hund

Cancerous cells reprogram healthy cells

For the development of tumors and the progression of a carcinoma, not only the characteristics of the cancer cells themselves are decisive, but also the cells surrounding the tumor play a major role in this. Many tumors even have the capability to reprogram healthy cells in the tumor environment in a way that they start to support the growth of the cancerous cells. This mechanism plays an essential role in human breast carcinoma – but is it the same for dogs? The similarity of breast carcinoma in dogs and humans has been known for a long time. “But whether these tumor cells also influence the surrounding tissue in dogs the same way they do in humans was unknown until now”, explains Enni Markkanen of the Institute of Pharmacology and Toxicology of the Vetsuisse Faculty of the University of Zurich.

Archived tissues are of great value to the research

The researchers analyzed the surrounding tissue of canine mammary tumors using molecular biology and immunohistological methods. To do this, they could access the tissue archive of the Institute of Veterinary Pathology located at the Animal Hospital. “With the permission of our patient’s owners, we conduct pathological tests to better understand diseases,” says animal pathologist Alexandra Malbon. “In the process, we archive samples of various organs and tissues as these samples can be of great value to answer future research questions.”

Dogs suffering from cancer aid cancer research for humans

In the archived samples of mammary tumors from dog patients, Enni Markkanen and her team were able to prove that some cells in the vicinity of tumors behave the same way as the corresponding cells in humans: In the healthy tissue surrounding the tumor, substances are produced that promote tumor growth. “Simply speaking, the tumor enslaves its environment: It forces the surrounding cells to work for its benefit,” Markkanen adds. This mechanism works the same in both humans and dogs. For research on breast carcinoma, tumor tissue of dogs is therefore, among other reasons, much better suitable than tissue from rats or cells cultivated in the laboratory. “Importantly, however, we don’t view our dog patients as test subjects for cancer research,” Markkanen says. “But they can help us to better understand breast carcinoma in both dogs and humans and fight it more effectively.”

Source:  University of Zurich media statement

Scientists test nanoparticle drug delivery in dogs with osteosarcoma

At the University of Illinois, an engineer teamed up with a veterinarian to test a bone cancer drug delivery system in animals bigger than the standard animal model, the mouse. They chose dogs – mammals closer in size and biology to humans – with naturally occurring bone cancers, which also are a lot like human bone tumors.

wikimedia-commons-photo-of-bmd

Dogs with naturally occurring cancers are more similar in size and biology to humans than are other mammals, such as mice. Public domain photo: Wikimedia Commons

In clinical trials, the dogs tolerated the highest planned doses of cancer-drug-laden nanoparticles with no signs of toxicity. As in mice, the particles homed in on tumor sites, thanks to a coating of the drug pamidronate, which preferentially binds to degraded sites in bone. The nanoparticles also showed anti-cancer activity in mice and dogs.

The researchers report their results in the Proceedings of the National Academy of Sciences.

These findings are a proof-of-concept that nanoparticles can be used to target bone cancers in large mammals, the researchers said. The approach may one day be used to treat metastatic skeletal cancers, they said.

The dogs were companion animals with bone cancer that were submitted for the research trials by their owners, said U. of I.  Professor Dr Timothy Fan, who led the study with materials science and engineering Professor Jianjun Cheng.  All of the dogs were 40 to 60 kilograms (88 to 132 pounds) in weight, he said.

“We wanted to see if we could evaluate these drug-delivery strategies, not only in a mouse model, but also at a scale that would mimic what a person would get,” Fan said. “The amount of nanoparticle that we ended up giving to these dogs was a thousand-fold greater in quantity than what we would typically give a mouse.”

Using nanoparticles with payloads of drugs to target specific tissues in the body is nothing new, Cheng said. Countless studies test such approaches in mice, and dozens of “nanopharmaceuticals” are approved for use in humans. But the drug-development pipeline is long, and the leap from mouse models to humans is problematic, he said.

“Human bone tumors are much bigger than those of mice,” Cheng said. “Nanoparticles must penetrate more deeply into larger tumors to be effective. That is why we must find animal models that are closer in scale to those of humans.”

Mice used in cancer research have other limitations. Researchers usually inject human or other tumor cells into their bodies to mimic human cancers, Fan said. They also are bred to have compromised immune systems, to prevent them from rejecting the tumors.

“That is one of the very clear drawbacks of using a mouse model,” Fan said. “it doesn’t recapitulate the normal immune system that we deal with every day in the person or in a dog.”

There also are limitations to working with dogs, he said. Dogs diagnosed with bone cancer often arrive at the clinic at a very advanced stage of the disease, whereas in humans, bone cancer is usually detected early because people complain about the pain and have it investigated.

“On the flip side of that, I would say that if you are able to demonstrate anti-cancer activity in a dog with very advanced disease, then it would be likely that you would have equivalent or better activity in people with a less advanced stage of the disease,” Fan said.

Many more years of work remain before this or a similar drug-delivery system can be tested in humans with inoperable bone cancer, the researchers said.

Source:  Illinois News Bureau media release

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

The history of canine transmissible venereal cancer

Researchers at the University of Cambridge have produced this interesting YouTube video about how canine transmissible venereal cancer has spread over time.  If you are interested in evolution, genetics or DNA research – this video is for you.

See also my previous posts:

A dog cancer that is 11,000 years old

Global snapshot of infectious canine cancer

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

 

Clinical trials to help beat cancer

Raelene Wouda’s passion for improving cancer treatment starts with our four-legged friends.

Dog cancer photo
Wouda, Kansas State University assistant professor of clinical sciences, is conducting clinical trials to treat cancers in dogs, cats and other companion animals.

When pet owners bring their dogs, cats, horses and other animals to the College of Veterinary Medicine’s Veterinary Health Center for treatment, Wouda and the Oncology Service can offer groundbreaking new treatments often at a lower cost to pet owners.

Wouda also is able to study important topics, such as improved diagnostic testing, monitoring approaches and innovative treatment options, including anti-cancer vaccines, t-cell transfer, combination chemotherapy and nanoparticle drug formulations. She has recently published her research in Veterinary Comparative Oncology and the Journal of the American Veterinary Medical Association.

“Although surgery, radiation therapy, chemotherapy and, more recently, immunotherapy have improved patient outcomes, many cancers still do not have a long-term cure,” said Wouda, a clinical veterinary oncologist. “These clinical trials are a crucial step.”

But Wouda’s research benefits humans, too. Many cancers in animals — especially dogs — are similar to those in humans, which means that the diagnosis, monitoring, treatment and response to treatment are also similar.

“Any research that we do in our patients has the potential to provide important information for how the disease can be better diagnosed, monitored and treated in human patients,” Wouda said. “That’s what I would like to do with our research. I would like to continue to improve outcomes for our veterinary patients and, by extension, help human cancer patients.”

Companion animals offer several research advantages. Wouda’s clinical trial program focuses primarily on dogs because of the similarities between their cancers and human cancers, such as osteosarcoma, melanoma, lung cancer and urogenital cancers. Osteosarcoma, for example, is both clinically and genetically almost identical in dogs and human pediatric patients.

Dogs also live with us and are exposed to the same environmental factors. Additionally, because dogs age faster than humans — one dog year is equivalent to seven human years — their diseases progress faster, which is a practical advantage for rapidly evaluating a new treatment’s efficacy and clinical benefit, Wouda said.

“We get clinical answers more quickly in dogs,” Wouda said. “The benefit of a particular therapy becomes evident in dogs more rapidly compared to people, and because of this we can preserve research and development finances, but more importantly, we save valuable time and resources.”

Animal clinical trials are structured similarly to human clinical trials and are tightly regulated and overseen. Wouda works with Mary Lynn Higginbotham, associate professor of clinical sciences, their graduate students and oncology technicians as well as the Veterinary Health Center’s referring veterinarians to conduct these clinical trials. They also collaborate with human medical researchers to discuss how the research can best be applied in the field of human oncology.

“For many pet owners, cancer is a terminal diagnosis for their beloved family member,” Wouda said. “These studies provide owners an opportunity to trial a cutting-edge therapy for their pets at a reasonable price. Moreover, owners participating in these clinical trials take comfort and are pleased to know that they are helping to achieve better treatments and outcomes for pets that may be diagnosed with cancer in the future.”

Source:  Kansas State University

The companionship of dogs helps kids undergoing cancer treatment

Although survival rates for children diagnosed with cancer have increased dramatically over the past 40 years, hard evidence of proven psychosocial benefits to improve quality of life among patients and families during treatment has remained elusive.

Many hospitals have therapy dogs who visit with patients, and anecdotal evidence underscores the positive impact these programs have on children with cancer and their families.

Preliminary findings from a new, multi-center trial provides some of the first quantitative data to validate these claims.  The study, to be presented at the American Academy of Pediatrics (AAP) National Conference & Exhibition in Washington, DC, collected data on blood pressure, pulse rates and anxiety levels of children before and after a weekly visit from a therapy dog. During the visits, children pet or talk to the dog, brush its fur, view the dog’s photos, watch the dog practicing tricks or commands, and learn about dog breeds.

Photo courtesy of University of Texas Health Science Center

Photo courtesy of University of Texas Health Science Center

Preliminary findings show that blood pressure readings in the group receiving animal-assisted interventions remains more stable across all sessions than in the control group, said lead researcher Amy McCullough, Ph.D., National Director of Humane Research and Therapy for the American Humane Association. Similarly, there was a higher degree of variability in heart rate within the control group patients than with the treatment group patients.

“These findings suggest that the dog may have a calming effect on the patient,” Dr. McCullough said.

In addition to the effects on pulse and heart rate to date, preliminary results indicate the canine encounters appear to improve anxiety levels among parents. Parents in the control group report fluctuating anxiety levels with peaks and valleys; parents in the treatment group show more consistency in anxiety levels, and even a small decline in anxiety levels by the end of their participating in the study. Overall, children in both groups saw a decrease in anxiety over the course of their study enrollment. Researchers are also gauging the therapy dogs’ temperament and behavior during the visits.

“This study will be a milestone in understanding of the benefits of the vital bond shared between people and animals,” Dr. McCullough said.

Source:  American Academy of Pediatrics media release

Puppy Up to Cancer

You’ve probably heard the terms ‘man up’ or ‘woman up’ – but how about ‘puppy up’?

That’s the origin of the name for the Puppy Up to Cancer initiative founded by the 2 Million Dogs Foundation.  Through every Puppy Up walk, funds are raised to help with cancer research.

Walks are usually led by human and canine survivors of cancer and often dogs who are infirm or who can’t walk for long distances participate by riding in wagons and carts.

Dogs are often used in comparative oncology studies because their cancers have commonalities with human cancers.

I think this  is a great idea and since we have many dogs in New Zealand who also fall to cancer, fundraising in this way would be a way of contributing to the body of knowledge.

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, Canine Catering Ltd, Christchurch, New Zealand