FIG. 2.

The bone marrow compartment demonstrates oxygen concentrations that range from 1% (furthest for the blood supply) to 7% (closest to the blood supply). Low oxygen concentrations have been referenced as a factor contributing to the protection and quiescence of HSCs. However, upon transformation, LSCs may demonstrate increased levels of metabolism and ROS levels, while maintaining a lower antioxidant capacity than their downstream progeny. This difference, a product of the oxygen environment, may allow for a differential redox insult and targeting of LSCs over normal HSCs driven by the introduction of a redox-active compound. HSC, hematopoietic stem cell; HSPC, hematopoietic stem/progenitor cell; LSC, leukemic stem cell; ROS, reactive oxygen species. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars