Blind Mole Rat Evolves Different Way to Fight off Cancer
Subterranean rodents are known to have built-in mechanism to fight off cancer.
Until now, it was believed that different rodent species follow the same mechanism that cancer-resistant naked mole rats use to ward off cancer. But a new study has found that rodents have evolved more than one way to avoid cancer.
Three years ago, biologists Vera Gorbunova and Andrei Seluanov at the University of Rochester studied the anti-cancer mechanism in naked mole rats by multiplying their cells in a culture dish.
Cells from most animals that are developed in a culture dish divide until they form a single layer of cells covering the base of the dish. While healthy cells stop dividing, cells affected by cancer continue to divide. However, experts noticed that the cells belonging to naked mole rats ceased division much faster than cells from other species, a report in Nature said.
They found that the rats used a specific gene called p16, which makes the cancerous cells oversensitive to the crowd and stops them from multiplying further.
Gorbunova and Seluanov believed that subterranean rodents will follow the same mechanism as the naked mole rats. But they found that the blind mole rats, which are a subterranean species and relatives of the naked mole rats, have developed a different mechanism to fight cancer.
Researchers isolated the cells from the blind mole rats and forced them to multiply on the culture dish. They found that the cells in the culture dish died rapidly, after dividing for about 20 times.
Experts noticed that the cells secreted a suicidal protein called interferon beta once they identified their pre-cancerous state. The protein killed pre-cancerous 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," Seluanov said in a statement.
It is not clear how the cells were able to sense when they are likely to overproliferate. Experts hope the discovery will help in developing new cancer therapies in humans. They are further planning to study what triggers the cells to secrete the protein.
"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," said Gorbunova.
Researchers believe that the rats might have developed the anti-cancer mechanism to adapt to their subterranean life, where they live in burrows protected from predators. "Living in this environment, they could perhaps afford to evolve a long lifespan, which includes developing efficient anti-cancer defenses," said Gorbunova.
The findings of the study, "Cancer resistance in the blind mole rat is mediated by concerted necrotic cell death mechanism," will be published this week in the Proceedings of the National Academy of Sciences.