UPDATED: Dog data at AACR cancer confab may point to personalized treatments

The annual meeting of the American Association for Cancer Research (AACR) is dedicated to presenting the latest results of promising trials in people--but this year one study that may help both human and canine cancer patients made a splash. During the closely watched conference, held in Philadelphia, researchers from the University of Colorado Cancer Center and Colorado State University Flint Animal Cancer Center presented a gene expression model that veterinarians can use to predict how dogs with osteosarcoma will respond to the commonly used chemo drug doxorubicin.

The researchers used a model developed at the CU Cancer Center called COXEN (CO-eXpression gEne aNalysis). It's based on the notion that cancer should be defined by its genetic alterations, rather than its location in the body. The model evaluates genes known to be important in the development of cancer, then compares the "genetic signature" of particular cancers to signatures of cancers for which data exists on how patients responded to treatment regimens, according to CU Cancer Center's blog.

If the genetic signature of a particular patient's cancer matches that of patients who responded positively in the past to a specific treatment, the oncologist could make a better-informed choice of drug regimen. The same is true of dogs and their veterinarians, said Daniel Gustafson, CU Cancer Center investigator and director for basic research at the Flint Animal Cancer Center, in the blog story.

The two most widely used treatments for bone cancer in dogs are doxorubicin and carboplatin. Some dogs respond better to one or the other, but it's difficult for veterinarians to know which choice is best until they actually try one.

"This study shows that we can use the COXEN model to accurately predict our patients' responses to doxorubicin," Gustafson said. "But the key here is that in addition to it being a personalized medicine approach for dogs, we are using veterinary science to further validate this tool that could help human cancer patients."

CU is currently conducting human trials comparing tumor samples evaluated with COXEN to the results of the chosen treatments.

Pet dogs with osteosarcoma are considered to be among the most realistic models of human bone cancer. So studies in one species invariably end up helping the other. And several companies investigating potential treatments for human bone cancers have turned to veterinarians for help validating their ideas. Among those companies is Princeton, NJ-based Advaxis ($ADXS), which reported positive Phase I results for its drug candidate in canine osteosarcoma late last year.

Advaxis has partnered with Aratana Therapeutics ($PETX) to move the drug (ADXS-HER2/AT-014) forward in dogs, while it continues to study the compound as a potential treatment for pediatric osteosarcoma. During the AACR meeting, the lead investigator for Advaxis' dog trial presented data showing that the drug combined with radiation maintained or improved limb function and that the median survival among 10 dogs treated was 285 days to date, compared with 136 days in dogs treated with radiation alone.

The data "were quite compelling and demonstrate the significant value that AT-014 offers as a potential treatment for canine osteosarcoma," said Steven St. Peter, CEO of Aratana, in a press release issued April 27.  

- here's the University of Colorado blog item
- read Aratana's press release

Editor's note: This story was updated to include the AACR data on ADXS-HER2/AT-014.

Read more on