Could tumours help us explain the explosion of life of Earth? Scientists have typically explained the period of history when large animal species became much more diverse very quickly as the result of the planet’s rising oxygen levels.
There are trillions of cells in the human body and we renew as many cells of them every year. The stem cells reside quietly in our tissues until new cells are needed. Stem cells generally don’t like oxygen because it causes them to lose their ability to make new cells. Tumours are groups of cells with uncontrollable growth, that start as a single cells and successfully make the leap to multicellular entities. Tumours also have their own cancer stem cells that help them whether or not there is lots of oxygen present.
To maintain these stem cell properties, especially when oxygen is plentiful, they get help from a specific biological mechanism, a protein referred to has HIF-2a. Our idea is that these proteins allowed multicellular organisms to finally cope with lots of oxygen.