CIRM grantees at UCSF have made a discovery that helps explain how stem cells in the body keep track of when to make more of themselves and when to produce non-stem cells. This work is important for scientists trying to harness stem cells in the body as disease therapies.
Their work involves a protein called BMI1, which is known to help stem cells replenish their populations, but also plays a role in cancer cells. It’s active in many kinds of cells, such as blood, brain and lungs. The researchers found that BMI1 also prevents misguided differentiation among stem cells – keeping them from maturing into the wrong kind of cells.
The group studied mouse incisors, which grow continuously throughout the mouse’s lifetime, unlike human teeth. In a paper published on Friday July 19 in the scientific journal Nature Cell Biology, they described how they found colonies of adult stem cells at the base of the incisor, which had high levels of the BMI1 protein. They found that BMI1 helps keep the stem cells in a stem cell state.
BMI1 might one day be incorporated into stem cell treatments, if scientists can find a way to harness its ability to marshal specialized cell development, according to Ophir Klein, the senior author of the study.
Stem cell scientists are also learning that cancers are probably caused by out-of-control adult stem cells or cells that take on stem-cell-like properties at the wrong time. Turning BMI1 off in these cells could prevent or slow cancer cell growth. In a press release, Klein said
“This new knowledge is useful in a fundamental way for understanding how cell differentiation is controlled, and may help us manipulate stem cells to get them to do what we want them to do.”
Klein and his research team plan to keep exploring this line of research, looking next at how stem cells are affected by signals they get from cells around them.