You think elections are stressful? They’re nothing compared to the threats faced every day by blind mole rats. According to Eviatar Nevo, from the University of Haifa, quoted in Nature News,
These animals are subject to terrific stresses underground: darkness, scarcity of food, immense numbers of pathogens and low oxygen levels. So they have evolved a range of mechanisms to cope with these difficulties.
One of these mechanisms is resistance to cancer. That’s right: blind mole rats and their subterranean cousins, naked mole rats, are the only mammals known never to develop cancer.
Three years ago, a team of researchers published a study of how naked mole rats avoid the disease. In these animals, cancerous cells get claustrophobic and stop multiplying. The 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.
Scientists figured it would be the same in blind mole rats. Nope!
A paper published this week in the Proceedings of the National Academy of Sciences finds that precancerous cells in blind mole rats commit suicide!
The researchers isolated cells from the animals, grew them on a culture plate, and forced them to proliferate in numbers beyond what occurs in the animal. After dividing approximately 15-20 times, all of the cells 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 protein kills both abnormal cells and their neighbors, resulting in a “clean sweep.”
“Not only were the cancerous cells killed off, but so were the adjacent cells, which may also be prone to tumorous behavior,” says co-author Andrei Seluanov of the University of Rochester.
Lead author Vera Gorbunova, also of the University of Rochester, believes the anti-cancer mechanism evolved as an adaptation to subterranean life. “Blind mole rats spend their lives in underground burrows protected from predators. Living in this environment, they could perhaps afford to evolve a long lifespan, which includes developing efficient anti-cancer defenses.
“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,” says Gorbunova.
Image: University of Rochester