AMCs home specifically to MM-enriched BM niches. (A) Expression of CD31, CD34, and CXCR7 on HUVECs, as a model for AMCs. (B) Migration of HUVECs to BM supernatant from normal subjects and MM patients normalized to the average of migration of normal subjects. (C) Migration of HUVEC cells to conditioned culture media from MM cell lines that were incubated in the media for 24 hours before the migration test, normalized to migration to nonconditioned culture media. (D) A schematic description of the procedure. (E) MM tumor progression in the right and left tibias after intratibial injection of MM1.S cells into the right tibia. (F) Differential homing of HUVECs to tibias with higher involvement of MM after IV injection.