Published February 07, 2012
Man’s best friend may help out their human cohorts by bringing in the paper or fetching someone's slippers. But now our canine companions may help us find improved cancer drugs.
Researchers from the University of Texas MD Anderson Children’s Cancer Hospital in Houston, in collaboration with the Texas A&M University College of Veterinary Medicine in College Station, used an innovative type of T-cell therapy in addition to routine chemotherapy treatment. The researchers saw a nearly four-fold improvement in survival rates for the dogs that received both therapies in comparison to the dogs who just received chemotherapy treatment.
Ultimately, they were able to increase the dogs’ tumor-free survival by nine months. In a human life, that could equate to seven years.
Dr. Laurence Cooper, section chief of cell therapy at MD Anderson and senior investigator on the study, said their treatment on dogs could potentially be a very close mirror to human treatment, more so than other animal models.
“For years we’ve used mice and rodents as the model, but that’s reached the point of diminishing returns,” Cooper told FoxNews.com. “A mouse model in terms of human biology can be very helpful, but can have limitations when understanding the human immune system.”
The problem with mice and rodent models lies in the complexity of humans. Not only are humans so dissimilar from rodents, but individual people are also genetically dissimilar from one another. The dog mirrors that complexity with its diverse background in terms of breeds and intermingling.
To test their new therapy, the researchers extracted T-cells – a type of white blood cell needed for immune response – from blood samples taken from each dog. They were then able to recreate and grow many more T-cells outside of the dogs’ bodies as they underwent chemotherapy. This allowed the synthetically generated T-cells to remain unharmed.
“The problem with chemotherapy is that it doesn’t just wipe out the tumor, but it also wipes out the immune system, just as it would in humans,” Cooper said. “Chemotherapy kills replicating cells, and one of the facets of your body that replicates often is your immune system.”
If a cancer cell isn’t killed by chemotherapy, it is instead transformed into what is known as an immunogenic cell. Immunogenic cells release antigens that basically act as red flags that help the immune system locate and destroy the remaining cancer cells. But since chemotherapy typically kills most of a person’s T-cells, this process usually doesn’t take place and relapse inevitably occurs.
To counteract this problem, Cooper and his team reinserted the healthy T-cells into the dogs after they had received their chemotherapy treatments. Just as the team had expected, the healthy T-cells were able to hunt down the remaining cancer cells and essentially eradicated the cancer.
Cooper said that the next step is to move this process from the canine patient to the human patient.
“We have several clinical trials based on this ‘add back’ of T-cells in clients,” Cooper said. “Those trials have been reviewed by the FDA, and we have our first patients lined up to go.”
Another success of their research, according to Cooper, is the creation of a new type of animal model that could prove more effective than any other type of animal model that has come before.
“What’s so compelling is this system that’s been set up has paved the way for canine therapy to be used as a model for human therapy,” Cooper said. “It’s a safer method in that we have to be careful because these are people’s precious pets. We treated the canine patient at the same level as if they were a human patient. We manufactured the cells at the same level of integrity as if they were being used for human application.”
Cooper added, “The dog is a man’s best friend, and now a dog with cancer is a human with cancer’s best friend. They’re so alike and so similar, that each helps one another.”
The team’s research was published this week in the journal Scientific Reports.