Objective: To determine the inhibitory effects of anti-bone sialoprotein(BSP) antibody on human breast cancer cells adhering to bone matrix in vitro.Methods: Expression of BSP in 3 different cancer cell lines(bone seeking breast cancer cell MDA-MB-231-BO,lung adenocarcinoma cell SPCA-1 and colon carcinoma cell LOVO)was detected immunohistochemically.Cells adhering test was carried out to investigate the adhering of the 3 different cancer cell lines to mouse bone matrix in vitro and the inhibitory effect of anti-BSP antibody on MDA-MB-231-BO cells adhering to mouse bone matrix;Enzyme-linked immunosorbent assay was carried out for quantitative detection of TGF-?.Results: BSP immunostaining was positive in MDA-MB-231-BO cells and negative in SPCA-1 and Lovo cells.The number of MDA-MB-231-F10 cells adhering to mouse bone matrix was significantly more than SPCA-1 or Lovo cells(P