This research reveals that metastatic tumor cells in the bone marrow actively hijack specialized macrophages to steal the iron supply typically used for blood production. These specific immune cells, known as erythroblastic island (EBI) macrophages, normally act as "nurse cells" by providing iron to developing red blood cells. By diverting these essential minerals to support their own growth and adaptation to low-oxygen environments, cancer cells effectively starve the blood-building process. This metabolic theft results in impaired erythropoiesis, explaining why patients with bone metastasis frequently suffer from severe anemia. The findings suggest that tumors mimic the features of developing red blood cells to exploit existing nutrient transport pathways within the bone niche. Knowledge of this interaction identifies a critical link between cancer progression and common hematologic complications, offering potential new targets for therapeutic intervention.

References:

• Han Y, Sarkar H, Xu Z, et al. Tumors hijack macrophages for iron supply to promote bone metastasis and anemia[J]. Cell, 2025, 188(22): 6335-6354. e26.