ARTICLES Preferential Adhesion of Prostate Cancer Cells to a

cancer, the disease metastasizes to bone and causes osteo-blastic growth. However, the mechanisms that contribute to bone metastasis are poorly understood. It has been hypoth-esized that the bone provides a favorable growth environ-ment for prostate cancer cells, which nonselectively seed the bone marrow from the bloodstream. Alternatively, prostate cancer cells may preferentially bind to bone marrow endo-thelial cells. We developed an in vitro model of bone endo-thelium and tested the hypothesis that prostate cancer cells adhere preferentially to bone marrow endothelial cells. Methods: We isolated and characterized a human bone mar-row endothelial (HBME-1) cell line. Cells were transfected with the simian virus 40 large T antigen for immortalization. Cell surface receptors were characterized by immunohisto-chemistry and flow cytometry. The adhesion of cancer cell