By Monika Joshi
Their eyes and ears seem to be missing, but that’s not the only thing that makes blind mole rats an odd bunch.
The furry rodents are also highly resistant to cancer, a new study says—raising the possibility of new cancer treatments for humans.A lesser mole-rat in Bulgaria. Photograph by Emil Enchev, Alamy
Researchers Aaron Avivi, Imad Shams, and Irena Manov of the University of Haifa in Israel conducted a two-part study to determine whether blind mole rats are resistant to chemically induced cancers and if their bodies can suppress tumors.
Twelve blind mole rats were treated with two potent carcinogens, 3MCA and DMBA/TPA, and only one of them developed a tumor. When the same experiment was conducted on mice and rats, those animals all developed malignant tumors, according to the study, published August 9 in the journal BMC Biology.
In the second part of the study, when cancer cells were placed into a medium with healthy blind mole rat cells, the cancer cells stopped dividing and even decreased in number. This did not occur in the case of mice and rat cells, leading the team to conclude that blind mole rat cells release a substance that inhibits cancer cells from growing. The next step is to pinpoint this unknown substance.
“If we succeed to identify, isolate, and clean the substance [their cells] secrete, we are on the way to testing it clinically and hopefully reaching a medicine” for people, Avivi said by email. (Also see “Putting the Brakes on Cancer’s Evolution.”)
Living Long and Prospering
Previous studies on blind mole rats and their relatives, naked mole rats, have revealed similar cancer resistance.
“Investigating these cancer-resistant creatures is extremely important,” Vera Gorbunova, of the University of Rochester, said by email. In 2012, Gorbunova’s team—which was not involved in the new study—found that blind mole rat cells were able to eliminate precancerous cells by secreting a protein called interferon-beta.
A more recent paper by the same group identified a protein they believe is responsible for stopping tumor growth in naked mole rats.
So why did mole rats evolve to beat cancer? To live long and withstand the low-oxygen, underground environment in which they live.
Mole rats can live for more than 20 years—about five times longer than lab mice and rats—and show no clear signs of aging. The burrowers can thrive in low-oxygenated areas, making them extremely tolerant of hypoxia, a condition in which the body is deprived of oxygen.
“Burrowing animals are safe from predation, and evolutionary theory predicts that, as a result, natural selection will yield animals that can breed later in life,” Jonathan Licht of Northwestern University said by email. “Evolution has achieved what are two goals of modern biomedical research: life extension and freedom from cancer.”
Who knew rats could teach us so much about defeating cancer?
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