Most cells in an organism can detect when they become cancerous and know how to shut them self-down (called apoptosis). However, the blind mole rat and the naked mole rat have an immune system that attacks tumors cells to shut them down (called necrosis). New genetic research show that genes involved in this immune defence have been favored by evolution.
Some of those genes are mutated in the mole rats as part of their adaptation to low oxygen. Some mutations produce for example lower P53 protein levels.
The mole rat species have spent their entire lives under the ground, where oxygen is scarce.
In other animals, this would increase p53 levels which would mean that some cells would die from apoptosis, but not in blind mole rats. They have evolved a unique evolutionair trade-off, weakening p53 and boosting the immune system’s defence (increasing necrosis), an immune system in over-drive eliminate all cancer cells in the mole rat.
This mechanism has fascinated researchers all over the world who study aging and cancer. Mole rats can live up to 30 years, about nine times longer than mice of the same size.
Scientist have studied mole rats for many years and they never reported a mole rat with cancer
. That is way long have been thought that mole rats cannot get cancer. Until a 22-year-old male mole rat at the Brookfield Zoo in Chicago developed a mass on its upper right chest. The mass measured 1.5 cm in diameter. Scientist removed and studied the mass, and reported that it looked like a malignant tumor from the mammary or salivary gland.
Even though we know now, that also mole rates get cancer scientist are still interested in the its defence mechanisms like the P53 protein. It is extraordinary that they can life for 30 years without developing cancer. Therefore, both the blind mole rat and the naked mole rat genome are sequenced. And both show interesting mutations and gene duplications.