Elephants and Cancer

Wondrous in a Whole New Way

Many of us are elephant fans. Whether we have seen them in films, on television, at zoos, or, if we are really lucky, in Africa or Asia, we are fascinated. We like the way they protect their young; we often like their matriarchal society, and we are moved by the descriptions of their grief when one of their family dies. There is also something compelling about their size. How can anything so immense move so quickly and quietly? How can anything so enormous be so much like us?

Having been to Africa several times, I have many wonderful memories of watching herds at water holes or moving together across the plains. I also have a not so wonderful memory of a young bull making a fake charge at our jeep. And I have a semi-wonderful memory of being reluctant to leave the tent for breakfast because of the mother and baby crunching on trees right along the path. We waited until they had moved on.

These thoughts are stimulated by a new report that elephants have a zombie gene that may help protect them from cancer. Called LIF6, it seems to shut down cells that have been threatened by cancer. Instead of those dangerous cells continuing to grow and divide, they die.

Elephants have evolved a way to make LIF6 (a non-functioning, or dead, gene in mammals) come back to life, and it's what makes the largest living land mammals nearly immune to cancer. In response to DNA damage, such as that caused by mistakes during cell division or by ultraviolet rays, the elephant version of the tumor-suppressing protein p53 prompts "zombie" LIF6 to efficiently kill cells poised to become cancerous. The research was published August 14 in the journal Cell Reports. "Elephants get cancer far less than we'd expect based on their size, so we want to understand the genetic basis for this cancer resistance," says senior author Vincent Lynch (@DevoEvoMed), a geneticist and evolutionary biologist at the University of Chicago. "We found that elephants and their relatives have many non-functioning copies of the LIF gene, but that elephants themselves evolved a way to turn one of these copies, LIF6, back on."

This is potentially hopeful science, but it is immediately wondrous news. Whether or not cancer researchers are ever able to move this discovery forward in ways that help cancer patients is not yet known. It is always a mistake to get too excited too quickly. There have been many other observations that have been interesting, but not clinically helpful. I love the idea, however, of elephants maybe giving us an important clue.

A caveat: We should be alert to schemes that use this information to sell products claiming to prevent or slow down cancer. Remember the hype some years ago about shark cartilage? The theory was that sharks don’t get cancer (not true; they just don’t get it very often), so that ingesting pills made of shark cartilage would benefit patients. As always, use common sense when considering such claims.

I am rooting for the elephants.