The article examines how bone tumors exploit macrophages to acquire essential iron, which concurrently promotes bone metastasis and causes anemia in cancer patients. Specifically, the research identifies a rare subpopulation of iron-recycling macrophages (iMac), resembling erythroblastic island macrophages, which are uniquely enriched near the tumor site and facilitate iron transfer to the malignant cells. This hijacking of the iron supply impairs normal red blood cell formation (erythropoiesis), leading to anemia, while simultaneously enabling tumor cells to survive the hypoxic bone environment by mimicking erythroblasts and upregulating hemoglobin through GATA1 signaling. Experimental depletion of these iron-rich macrophages impedes tumor growth and reverses the resulting anemia, suggesting that targeting this iron-transporting mechanism could be a dual therapeutic strategy for both metastasis and associated complications.

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.