We found that mice with ER-expressing E0771/Bone-derived tumors had significantly increased percentages of Sca-1-positive HSCs (64.4-fold increase) and endomucin-positive vasculature (2.8-fold increase) within the bone marrow when compared with TN E0771/Bone tumors (Supplemental Figure S8b). The gene discussed is ESR1; the disease is bone neoplasm.