At 400 million years old, the shark animal group is one of the oldest on the planet. So it’s no surprise it’s picked up some impressive tricks along the way.
Scientists know the ancient creatures are super effective wound healers, and they suspect they have a greater resistance to cancer too.
Now a new study suggests a link between sharks’ natural survival mechanisms and their fine-tuned immune systems, and it could pave the way for new approaches to treatments in humans.
Researchers identified two immune genes, legumanin and Bag1, which if over-expressed in humans are associated with cancer, but in sharks appear to have been modified as a result of natural selection.
It’s thought that the protein produced by the genes in sharks may have a new function, potentially protecting the animals from even acquiring cancer.
In people, the Bag1 gene is often involved in inhibiting cells’ death, preventing those that are dysfunctional from being eliminated.
But in sharks it’s suspected that the gene may have evolved to remove its tendency to inhibit programmed cell death.
“Several studies have demonstrated anti-tumor properties of shark-derived compounds in lab studies,” said Mahmood Shivji, the study’s co-lead and director of Nova Southeastern University’s Save Our Seas Shark Research Center.
“It’s intriguing that we are now seeing evidence of evolutionary adaptation in these specific shark immunity genes, which just happen also to be involved in promoting cancer in humans,” Shivji added.
He said that more research was required to confirm the notion that sharks are more resistant to cancers, stressing that eating shark meat would not cure or prevent cancer. The meat’s high mercury content could even damage our health.
“Now we have another important reason to make sure we don’t lose these marvellous and ecologically critical animals to overfishing, as is currently occurring in many parts of the world,” Shivji said. “We’ve just scratched the surface in terms of learning what these ancient animals can teach us, as well as possibly provide us in terms of direct biomedical benefits.”
Sharks aren’t the only creatures which could hold the clue to revolutionary cancer treatments. Earlier this month, scientists in the US announced they were looking at elephant DNA to determine whether certain proteins could kill cancerous cells, and even stop the disease from developing.