Funded in memory of Tony Smith, EdD, Member of the V Foundation Board, 2003-2017
Blood cancers, such as leukemia, often begin in the bone marrow where rare blood-forming stem cells regenerate normal blood cells throughout life. Many blood cancers can be eliminated with chemotherapy, but chemotherapy also destroys normal stem cells. Thus, many cancer patients depend on receiving stem cell transplants after therapy. Sadly, many patients are unable to receive life-saving transplants because of insufficient numbers of available stem cells. One way we can overcome this challenge is to develop ways to grow and expand blood-forming stem cells outside the body, but previous efforts to do so have been unsuccessful. Recently, we discovered that stem cells make new proteins much more slowly than other blood cells, and this slow rate of protein production is crucial for stem cell function. Proteins are the functional products of genes and perform many specialized tasks within cells. Making proteins too quickly increases assembly errors leading to the production of dysfunctional and toxic proteins. In contrast, producing proteins slowly helps ensure that new proteins are precisely assembled, are of high quality and function correctly. We found that growing stem cells outside the body increases the rate of protein assembly and decreases protein quality, which impairs stem cells. We are using new and innovative strategies to enhance protein quality within stem cells that could, for the first time, enable expansion of blood-forming stem cells in the laboratory. These discoveries could provide new therapeutic possibilities for numerous cancer patients.