Why Do Elephants Not Get Cancer In Spite Of Their Huge Bodies?

Elephants are friends of humans, and scientists have discovered something that could be a bigger help. One genetic mechanism makes these pachyderms fight tumor growth.

This discovery can help us to develop cancer treatment, according to Live Science.

Scientists examined 14 years of "necropsy data" gathered from the San Diego Zoo. Usually, the risk of cancer increases with body size and longer lives. Yet, it is low for elephants. They found that 4.8 percent of elephants are killed by cancer, which is surprisingly low as compared with the 11 to 25 percent of humans who are killed by cancer, according to natureworldnews.

When scientists examined its TP53 gene, they found that it suppresses tumor growth. However, for humans, this gene is mutated, which leads humans to increased cell reproduction and genome mutations.

Usually, humans get a pair of TP53 gene copies, one from either parent. Sometimes, just one copy works in a case called the Li-Fraumeni syndrome, which makes people 90 percent likelier to develop cancer than those who don't.

On the other hand, elephants tend to inherit 20 copies of the TP53 gene from each parent!

"We think that making more TP53 is nature's way of keeping this species alive," said Dr. Joshua Schiffman, lead study author and pediatric oncologist at the Huntsman Cancer Institute, University of Utah, in a press release.

There were three samples of blood taken and exposed to radiation from people with Li-Fraumeni syndrome---those who did not have Li-Fraumeni syndrome as well as elephants.

The scientists are aware that TP53 would attack and kill cells exposed to radiation. Researchers found after showing them to radiation that in those who had the Li-Fraumeni syndrome, just 2.7 percent of the cells died, while in those who did not have the syndrome, 7.2 percent of the cells were killed.

On the other hand, in elephants, 14.6 percent of the cells died, which totalled to twice as much as those in healthy humans.

"These findings, if replicated, could represent an evolutionary-based approach for understanding mechanisms related to cancer suppression," the study authors wrote.

The study was published in the Oct. 8 online issue of the journal JAMA.