Bone marrow vascular and stromal niche (BM niche)

The bone marrow vascular and stromal niche is a specialized microenvironment within the bone marrow that regulates the maintenance, proliferation, and differentiation of hematopoietic stem cells (HSCs) (Sugiyama & Nagasawa, 2012). It is anatomically and functionally organized into two primary compartments: the endosteal niche, located near the bone surface, and the vascular (perivascular) niche, centered around sinusoidal blood vessels (Frontiers in Oncology, 2022). These niches are composed of a diverse array of cell types, including mesenchymal stromal cells (MSCs), endothelial cells, osteoblasts, and CXCL12-abundant reticular (CAR) cells, which provide essential physical support and biochemical signals such as CXCL12 and stem cell factor (SCF) (NIH, 2023). In diseases like acute myeloid leukemia and multiple myeloma, the niche is often remodeled to create a protective environment that shields malignant cells from chemotherapy and promotes their survival (Nature Reviews Cancer, 2020). Therapeutic strategies targeting this niche aim to disrupt the adhesive interactions between cancer cells and the stroma, such as the CXCR4/CXCL12 or VLA-4/VCAM-1 axes, to mobilize malignant cells into the peripheral circulation where they are more susceptible to treatment (Blood, 2023).

Other names

Hematopoietic stem cell nicheBone marrow microenvironmentVascular nicheEndosteal nicheStromal nichePerivascular niche

Disruption of retention signals (CXCL12/CXCR4, VCAM-1/VLA-4), mobilization of hematopoietic stem cells, and modulation of the bone marrow microenvironment to enhance chemosensitivity.