Gooey Sugar Cells Key to Naked Mole Rats' Cancer Immunity

If the animal kingdom were to hold a beauty pageant, the naked mole rat, with its buck teeth and wrinkled skin, would have a hard time making it past the qualifying round. Still, scientists have long paid attention to the ugly rodent because of its seeming inability to get cancer. And the latest breakthrough in mole rat research indicates the same molecules that give the rodent its wrinkles also prevent it from getting cancer.

Technically a closer relative of the porcupine than the rat, the naked mole rat is an oddity of the natural world. They can live as long as 32 years and are one of only two known mammals to live in a colony in the service of a queen. The subterranean rodent does not feel the burn of chili pepper or the sting of acid and, according to Nature, scientists have never observed a naked mole rat with cancer.

The latest research points to a sugary substance in the rodent's skin cells as key to its cancer-fighting abilities. The naked mole rats' skin tissue is rich in high molecular weight hyaluronan (HMW-HA), a gooey sugar involved in tissue repair.

Researchers were tipped off to the potential importance of HMW-HA because cell cultures from mole rats would often be so full of HMW-HA that it clogged equipment in the lab. Other cell cultures from mice, humans and guinea pigs did not seem to have the same effect.

"We needed to understand what the goo was," said Andrei Seluanov, a University of Rochester researcher who led the mole rat study with colleague Vera Gorbunova.

In an experiment, the researchers removed HMW-HA from mole rat cells and found that, in its absence, the cells were susceptible to tumors, which confirmed that the sugary molecule did play a role in the mole rats' anti-cancer attributes. Researchers were able to identify the gene responsible for making HMW-HA, as well as observe that the mole rats were very slow in recycling their supply of the molecule, which is likely why it is found in such great quantities on the rodents.

Researchers also think the substance gives the mole rats their elastic, wrinkly skin, which is needed to squeeze through underground tunnels.

Later research will focus on whether HMW-HA is effective in preventing cancer in lab mice. If successful, the researchers hope to test the substance on human cells.

"There's indirect evidence that HMW-HA would work in people," said Seluanov. "It's used in anti-wrinkle injections and to relieve pain from arthritis in knee joints, without any adverse effects. Our hope is that it can also induce an anti-cancer response."

Commenting on the research, Oliver Childs of Cancer Research UK told BBC News that the research is fascinating, but not to expect any great breakthroughs in cancer prevention any time soon.

"It's a long way off, but it will be interesting to see if further research can find a way to use hyaluronan to help prevent or treat cancer in humans."