Bone marrow stromal and niche cells (BMSC)

Bone marrow stromal and niche cells constitute the specialized microenvironment within the bone cavity that governs the maintenance, self-renewal, and differentiation of hematopoietic stem cells (HSCs) (Morrison & Scadden, 2014). This niche is a complex assembly of various cell types, including mesenchymal stromal cells (MSCs), osteoblasts, endothelial cells, and sympathetic neurons, which provide essential physical support and regulatory signals such as CXCL12 and Stem Cell Factor (SCF) (Crane et al., 2017). Beyond normal physiology, these cells play a critical role in the progression of hematologic malignancies like leukemia and multiple myeloma by creating a "sanctuary" that protects cancer cells from chemotherapy and immune surveillance (Swerdlow et al., 2016). Therapeutic strategies targeting this niche include the use of CXCR4 antagonists like plerixafor to mobilize HSCs or malignant cells into the peripheral blood, and the administration of MSCs for their potent immunomodulatory properties in treating graft-versus-host disease (Le Blanc & Mougiakakos, 2012). Understanding the niche's molecular landscape is vital for improving stem cell transplantation outcomes and developing therapies that disrupt the protective environment of bone marrow-resident cancers (Nakamura-Ishizu et al., 2014). While the niche itself is a cellular compartment rather than a single molecular target, its components are increasingly targeted to overcome drug resistance in oncology.

Other names

Mesenchymal stromal cellsBone marrow microenvironmentHematopoietic stem cell nicheBMSCsMSCsBone marrow niche

Disruption of cell-cell adhesion (e.g., CXCR4/CXCL12 axis), mobilization of hematopoietic stem cells into peripheral blood, and modulation of the cytokine environment to inhibit the protective effects of the niche on malignant cells.