What do elephants and humans have in common? When it comes to deadly diseases, very little.
A study by the U, in collaboration with Arizona State University, examined cancer in the context of elephant DNA. Though 100 times larger than humans, elephants seldom develop the disease. Because of their size, “all elephants should be developing cancer … but they rarely, rarely do,” said Joshua Schiffman, an associate professor in the U’s Department of Pediatrics.
TP53 genes are responsible for the varying cancer rates in humans and elephants. The genes are essentially “spell checkers,” Schiffman said, as they identify and attempt to repair broken DNA pieces. If the DNA is unable to be repaired the genes coordinate cell death, known as apoptosis.
While humans have two copies of the TP53 genes, elephants have 40. The larger number of genes may be one of the ways the elephants are avoiding cancer, the study found. Schiffman said the researchers also found that elephant cells are “exquisitely sensitive to DNA damage.”
The study was conducted in collaboration with Utah’s Hogle Zoo, as well as with the Ringling Brothers Circus.
In 2013, Schiffman gave a presentation on the research done using the African elephants from the Hogle Zoo. Elephant scientists and veterinarians from the Ringling Brothers Circus, who attended, expressed interest in elephant research and began to regularly share the blood drawn from the circus’s elephants for cancer research.
“Because Ringling Brothers has the largest herd of Asian elephants in the Western Hemisphere, the Feld family felt compelled to help support this research,” said Sabrina Cullen, National Public Relations manager for Ringling Brothers at Feld Entertainment Inc., in an emailed statement.
The collaboration with the Ringling Brothers, as well as the circus’s interest in pediatric cancer, has resulted in the company providing donations to research at each show, through the Ringling Brothers Children’s Fund. The Feld family, which owns Ringling, will also donate $1 million to support cancer research, Cullen said.
Though the initial study has been completed and published, the researchers are now working with a collaborator from Israel. The next step is to understand how “we take this discovery and … use it therapeutically,” Schiffman said.
The TP53 gene is the most commonly mutated gene in all of human cancer. Many of the patients Schiffman works with as a pediatric oncologist have only one, meaning they have an almost 100 percent chance of developing cancer. In the general population, about half of all men and a third of all women will develop cancer at some point in their life. An increased number of TP53 genes in humans could potentially decrease the percentage of people suffering from the disease.
“This is a discovery 55 million years in the making,” Schiffman said. “We’re very excited in our lab … to be working to try to figure [this] out.”
@sarahnlegg