The Mechanism of Blind Mole Rat Cancer Immunity

Blind mole rats, like naked mole rats, do not appear to suffer from cancer - an aspect of their biology that probably drives more research interest at the moment than their exceptional longevity. The cancer suppression mechanism in naked mole rats has been explored in recent years, but here researchers discover that blind mole rats have evolved a different method of achieving the same end:

Blind mole rats and naked mole rats - both subterranean rodents with long life spans - are the only mammals never known to develop cancer. Three years ago, [researchers] determined the anti-cancer mechanism in the naked mole rat. Their research found that a specific gene - p16 - makes the cancerous cells in naked mole rats hypersensitive to overcrowding, and stops them from proliferating when too many crowd together.

"We expected blind mole rats to have a similar mechanism for stopping the spread of cancerous cells. Instead, we discovered they've evolved their own mechanism."

[The researchers] made their discovery by isolating cells from blind mole rats and forcing them to proliferate in culture beyond what occurs in the animal. After dividing approximately 15-20 times, all of the cells in the culture dish died rapidly. The researchers determined that the rapid death occurred because the cells recognized their pre-cancerous state and began secreting a suicidal protein, called interferon beta. The precancerous cells died by a mechanism which kills both abnormal cells and their neighbors, resulting in a "clean sweep." [The next step is] to find out exactly what triggers the secretion of interferon beta after cancerous cells begin proliferating in blind mole rats.

"Not only were the cancerous cells killed off, but so were the adjacent cells, which may also be prone to tumorous behavior. While people don't use the same cancer-killing mechanism as blind mole rats, we may be able to combat some cancers and prolong life, if we could stimulate the same clean sweep reaction in cancerous human cells."

Link: http://phys.org/news/2012-11-mole-rat-wards-cancer.html