Comparative Biology: Naked Ambition

See Inside

A subterranean species that seems to be cancer-proof is providing promising clues on how we might prevent the disease in humans

The naked mole rat has been extensively studied, but no cancer has ever been spotted in this species.

PHOTOTAKE/ALAMY

There is a lot not to envy about the life of the naked mole rat: imagine passing your days in a stuffy, pitch-black system of tunnels two or three metres underground with 100 of your closest relatives. But there is one thing that humans might covet: as far as anyone knows, the animal never gets cancer.

Native to the Horn of Africa, this small rodent (Heterocephalus glaber) is neither a mole nor a rat; it is actually more closely related to porcupines and guinea pigs. The animal's pale-pink, wrinkled skin is nearly hairless, the better to slip through those narrow burrows. But there is yet another more compelling fact: in all the thousands of naked mole rats that have lived and died in research labs and zoos over the past several decades, not a single instance of spontaneous cancer has been recorded1.

So far, the animal provides little more than a footnote to the vast body of cancer literature based largely on studies of laboratory mice. But the species has a few fierce advocates in the scientific community, who say that to truly defeat cancer we need to pay a lot more attention to naked mole rats and species like them.

If we want to learn what naturally occurring resistance mechanisms protect from cancer, we may not find them in mice because mice are even more prone to cancer than humans, says biologist Vera Gorbunova, who co-leads naked-mole-rat studies at the University of Rochester in New York. In some strains of mice, for example, cancer kills 90% of animals.

In other words, although mice are an excellent model for cancer development, progression and treatment, naked mole rats may be better for prevention. We have to study species that are more resistant, Gorbunova explains.

Researchers have found it tough to induce cancer in naked mole rats. Working in culture, they have infected cells from the creatures with a genetically engineered virus that contains a pair of oncogenes, or cancer-promoting genes, that reliably turns mouse cells malignant2,3. This common oncogenic cocktail had no effect on the naked-mole-rat cells, says Rochelle Buffenstein, a physiologist at the University of Texas, San Antonio, and a pioneer of naked-mole-rat research. They did not become tumorigenic, they didn't rapidly proliferate, they didn't invade tissues.

View original post here:
Comparative Biology: Naked Ambition