Tag Archives: lymphoma

Drug trials in pet dogs with cancer

Physiological similarities between dogs and humans, and conserved genetics between some dog and human cancers, can allow pet dogs to serve as useful models for studying new cancer drugs, says Dr Timothy Fan of the University of Illinois.

Timothy Fan, professor of veterinary clinical medicine. With his personal dog, Ember

Timothy Fan, professor of veterinary clinical medicine. With his personal dog, Ember  photo by L. Brian Stauffer

In a meeting sponsored by the National Cancer Policy Forum of the National Academies’ Institute of Medicine in Washington, D.C., Fan and 15 other experts in the field described the benefits of using pet dogs with naturally occurring (rather than laboratory-induced) tumors in early cancer drug trials.

“We have a lot of dogs in the United States, approximately 70 million of them, and it’s believed that about 25 percent of pet dogs will develop some form of cancer in their lifetime,” he said. “We’re using dogs to help guide drug development for people, but at the same time we’re offering new, innovative therapies that would otherwise never be available to dogs, to help them as well.”

Several attributes make pet dogs attractive subjects for such studies, Fan said.

“Dogs tend to develop cancer as a geriatric population, just like people,” he said. “Because the tumors develop spontaneously, there is heterogeneity in that tumor population, as a human being would have. The size of the tumors and the speed of growth of those tumors are comparable in dogs and human beings. So there are many attributes of a dog that develops cancer spontaneously that recapitulate the biology that we see in people.”

Some studies have already begun using dogs to test new cancer therapies. Starting in 2007, for example, Fan began testing an anti-cancer drug called PAC-1  in pet dogs with naturally occurring lymphomas and osteosarcomas. The results in dogs allowed the scientists to advance PAC-1 as a potential therapy against human cancers. The drug is now in phase I human clinic trials.

“Another example in which dogs have been important in demonstrating drug activity was an anti-cancer compound produced by the pharmaceutical company Gilead Sciences,” he said. “The company produced a pro-drug, which must be activated by a naturally occurring enzyme in human leukocytes before it can become effective. Mice and rats lack this enzyme, but dogs have it, so the compound was tested in dogs.”

There also are limitations to the use of pet dogs in cancer drug trials.

“There are some tumors that will not be that relevant,” Fan said. “Colon cancer, for example, is heavily driven by diet, and we don’t see much colon cancer in dogs. So pet dogs might not be a suitable model for colon cancer in humans.”

“There is heterogeneity in the human population and in dogs. So I would argue that if your drug agent produces positive results in dogs, that would give me greater confidence that those findings would be translatable to people.”

Source:  University of Illinois media release

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Diagnosing lymphoma in dogs

Nearly one out of four dogs will develop cancer in their lifetime and 20 per cent of those will be lymphoma cases.

A team of researchers from the University of Leicester has helped Avacta Animal Health Ltd to develop a new user-friendly electronic system for diagnosing lymphoma in dogs in the early stages, and for remission monitoring.

Marketed as cLBT (canine lymphoma blood test), this is the first test of its kind to track the remission monitoring status of a dog after undergoing chemotherapy.

Photo by Avacta Animal Health Ltd

Photo by Avacta Animal Health Ltd

Led by Professor Alexander Gorban from the University’s Department of Mathematics, the University team together with experts from Avacta elaborated technology for differential diagnosis of canine lymphoma and for remission monitoring.

This technology is based on the cLBT, which detects the levels of two biomarkers, the acute phase proteins C-Reactive Protein and Haptoglobin.

The paper ‘Computational diagnosis and risk evaluation for canine Lymphoma’ by E.M. Mirkes, I. Alexandrakis, K. Slater, R. Tuli and A.N. Gorban has been published in the academic journal Computers for Biology and Medicine and is available at the following location: http://dx.doi.org/10.1016/j.compbiomed.2014.08.006

Source:  University of Leicester media release

New Cancer Drug for Dogs Also Helps Humans

Dogs suffering from certain types of blood cancers may have a new treatment alternative thanks to the collaborative work of cancer experts looking for options that can help both humans and their pets.

The drug, Verdinexor (KPT-335), works by preventing powerful tumor suppressing proteins from leaving the nucleus of cells, an exodus which allows cancer to grow unchecked. It’s the first new therapeutic option for dog lymphoma in more than two decades, potentially offering vets another alternative for treating the disease, which is the most common form of canine cancer.

“Verdinexor is a really different from chemotherapy, the current standard of care for lymphoma. It works by blocking a protein in the cells responsible for shuttling other proteins in and out of the nucleus, resulting in disruption of cell survival and eventual cell death ,” said veterinary oncologist Cheryl London, DVM, PhD, The Ohio State University College of Veterinary Medicine, who led preclinical, Phase I and Phase II studies of Verdinexor. “Verdinexor could give veterinarians another option if first-line chemotherapy fails or as a potent adjunctive therapy.”

Lead researcher Cheryl London with her dog, photo courtesy of The Ohio State University College of Veterinary Medicine

Lead researcher Cheryl London with her dog, photo courtesy of The Ohio State University College of Veterinary Medicine

“A cancer diagnosis is tough on dogs and their owners. Dogs with lymphoma must go to a veterinary office weekly to receive chemotherapy infusions,” said London. “Since Verdinexor is a pill that can be given at home, it could help make treatment less traumatic for everyone.”

The similarities in the ways human and canine cancer drugs are researched and used are not coincidental. Many types of human and canine cancers are identical at both the cellular and molecular levels, making companion animal studies an ideal place to test drive experimental compounds that appear to have anti-cancer characteristics.

When it comes to cancer, dogs and humans have so much in common,” said London. “I think as human medicine becomes more personalized through the use of genomics, I think we’ll see the same happening in vet medicine.”

Source:  Newswise media release

Lymphomas in humans and dogs have similarities

A team of scientists from the University of North Carolina School of Medicine, North Carolina State University’s College of Veterinary Medicine and Duke University have conducted one of the first studies to directly compare canine and human B-cell lymphoma by examining molecular similarities and differences between the two species.

B-cell lymphomas are very common in both humans and dogs.

“Pet dogs get cancer the same way humans do: at similar rates, and for unknown reasons.  Like humans, dogs’ tumors are spontaneously occurring, rather than genetically created as they are in mice, so canine tumors may more accurately mimic the situation in human cancer patients. Dogs are good models to study, because it will also be possible to study shared risk factors, in the environment, for example, that might predispose both humans and dogs to get lymphoma. Our knowledge helps dogs and humans with lymphoma.” says Kristy Richards, MD, PhD, and co-author of the research which has been published in the journal Cancer Research.

“Veterinarians treating dogs for lymphoma can offer clinical trials to their owners. Clinical trials in dogs are similar to those done in humans, with safety protections in place to minimize harm.”

Molecular analyses of canine and human tumors were completed at NCSU and at UNC Lineberger. The team used gene expression profiling and found that canine B-cell lymphoma expression profiles were similar in many ways to human B-cell lymphoma, thus paving the way for future studies, including therapeutic clinical trials in dogs and humans.

Source:  UNC School of Medicine media statement

New research into virus infection in dogs

Researchers at the University of Pennsylvania School of Veterinary Medicine and the Perelman School of Medicine have published new research into an Epstein Barr-like virus that can infect and may cause lymphomas in dogs.

The findings means that humans and dogs share a similar biology – at least when it comes to the infection by the virus.  (Epstein Barr is the cause of diseases such as mononucleosis and is linked to the development of more serious diseases including non-Hodgkins and Hodgkins lymphomas.)

How does infection occur?

In humans, the Epstein Barr virus infects B cells.  After an acute phase of infection, which passes in many people without them even being aware of it,  the virus goes into a latent phase.  Most people show no symptoms during this phase.  In some, however the virus promotes unnatural growth of B cells and this contributes to the development of lymphoma.

Dogs develop lymphomas that share some characteristics with human lymphomas.  These conditions are relatively common in certain breeds such as the golden retriever.

Researchers think this line of enquiry is promising because they may be able to study the rates of infection and responses to treatment in dogs and this may have spinoffs for human treatment.

You can read the entire University of Pennsylvania media statement here.