Abstract
The impact of myeloid malignancies on the nonhematopoietic components of the bone marrow remains poorly understood. In this issue of Cell Stem Cell, Schepers et al. (2013) describe how malignant myeloid cells alter the endosteal hematopoietic stem cell (HSC) niche, resulting in the expansion of osteoblastic lineage cells that preferentially support malignant HSCs.