by Lauren Claus
Approximately 254,000 United States citizens currently have leukemia, a type of cancer in which abnormal blood cells, such as white blood cells, crowd and interfere with normal bone marrow function (1). Despite the range of treatments, including chemotherapy and bone marrow transplants, it is estimated that 7.1 out of 100,000 adults die each year from this disease (2). However, a recent study published in Cell Stem Cell points to new areas of investigation for treatment. Written in part by Amy Wagers of Harvard’s Department of Stem Cell and Regenerative Biology, the research focused on the question of why the bone marrow of leukemia patients can only produce cancerous cells—and not healthy cells, as well (3).
Although it was previously believed that the cancerous growth of leukemia simply crowded out and overwhelmed healthy cells, Wagers and her colleagues discovered that leukemia cells actually remodel bone marrow. By signaling maintenance cells in bone marrow to emit collagen and inflammatory proteins—which contribute to the buildup of scar tissue in the bone cavity—leukemia cells exploit bone marrow to suit their own needs. This altered microenvironment in the bone marrow is much more hospitable to the production of leukemic stem cells than that of hematopoietic stem cells, those that normally occur in the bone marrow and develop into mature blood cells.
This understanding of how cancerous growth impacts the bone marrow microenvironment has implications for novel leukemia treatments. Emmanuelle Passegué, one of the researchers of this study, has demonstrated that eradicating malignant bone marrow cells can cause the bone marrow environment to begin to return to its normal state; Passegué is now researching ways to regenerate normal bone marrow microenvironments in people suffering from leukemia. The results of this research could open up a wide variety of possibilities to the researchers still searching for cures and the patients who are waiting for them.
1–(2013). Statistics. Leukemia Research Foundation. Retrieved from http://www.allbloodcancers.org/statistics
2–Seer Stat Fact Sheets. National Cancer Institute. Retrieved from: http://seer.cancer.gov/statfacts/html/leuks.html#incidence-mortality
3–Schepers, et al. (2013). Myeloproliferative Neoplasia Remodels the Endosteal Bone Marrow Niche into a Self-Reinforcing Leukemic Niche. Cell Stem Cell, 13(3), 285-99.
4–(2013). Cross-Country Collaboration Leads to New Leukemia Model. Science Daily. Retrieved from http://www.sciencedaily.com/releases/2013/07/130731122948.htm
Harvard Science Review 