In search of an explanation, the scientists combed through the African elephant genome and found at least 40 copies of genes that code for p53, a protein well known for its cancer-inhibiting properties.
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The researchers uncovered one of the elephant’s secrets – it has nearly 20 times as many copies of a cancer-protective gene – called p53 – as people. In comparison, 11 percent to 25 percent of humans die of cancer. It was like cell death or cell suicide.
“These findings, if replicated, could represent an evolutionary-based approach for understanding mechanisms related to cancer suppression”, the study authors wrote.
Schiffman’s patients in clude children with incomp lete p53 genes because of a condition called Li-Fraume ni syndrome, which increa ses their chances of develo ping cancer. Lynch thinks that the extra copies evolved as the lineage that led to elephants expanded in size.
“We looked closely at our results”, says Schiffman “What we saw astounded us but made a lot of sense”.
Scientists have always been looking to animals for answers to cancer; first, studying why a few breeds of dogs exhibited a high level of cancer, while in others, it was a rare occurrence.
“These genes actually kill more than twice as many damaged cells as our genes do”, Schiffman said. These bonus genes might enable elephants to weed out potentially cancerous cells before they can grow into tumors.
Schiffman told the Los Angeles Times the next step will be to learn how TP53 can help human defenses and may create drugs that mimic the actions of TP553.
Dr. Schiffman is now investigating how to apply the new findings on human beings suffering from cancer. “If you just kill the cell, that’s the ultimate way of getting rid of the risk for cancer”, he says. The scientists extracted white blood cells from elephant blood drawn during routine wellness checks.
He points out, however, that modern humans are particularly vulnerable to cancer, which is more down to lifestyle factors – such as smoking – that are not seen in other animals.
The team at the University of Utah said “nature has already figured out how to prevent cancer” and plan to devise new treatments. “It is as if these elephant cells are on a high alert for any type of mutation, and as soon as they see it, they will get rid of that cell, so that it won’t go on to develop cancer”, sayd Schiffman. He also suggests that new technology such as nanoparticles might be able to deliver elephant p53 into human cells as a means for cancer prevention or treatment.
“The animal kingdom undoubtedly holds information that could help lead to cures for many human illnesses”, said Craig Dinsmore, executive director, Utah’s Hogle Zoo.
The study was done by researchers at Huntsman Cancer Institute (HCI) at the University of Utah and Arizona State University, as well as researchers from the Ringling Bros. and Barnum & Bailey Center for Elephant Conservation.
Naked mole rats and elephants protect against cancer in different ways, Seluanov notes.
To test the efficiency of these extra copies, researchers bombarded elephant cells with radiation, ultraviolet rays, and DNA-damaging chemicals.
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“Perhaps the main message from this innovative investigation is to bring into focus the question of why humans appear to be so ill-adapted to cancer, given the average size and life span. The human genome is replete with footprints of positive selection in the not-too-distant historical past”.
