title: BSP gene silencing inhibits migration, invasion, and bone metastasis of MDA-MB-231BO human breast cancer cells.
abstract: Bone sialoprotein (BSP) has been implicated in a variety of physiological and pathophysiological events, including tumor cell invasion, bone homing, adhesion, and matrix degradation. To explore the potential involvement of BSP in human breast cancer cell invasion and metastasis, we used retrovirus-mediated RNAi to deplete BSP levels in the human bone-seeking breast cancer cell line MDA-MB-231BO (231BO) and established the 231BO-BSP27 and 231BO-BSP81 cell clones. Cell proliferation, colony formation, wound healing, and the ability to invade into matrigel of these BSP-depleted clones were all decreased. Both 231BO-BSP27 cells and 231BO-BSP81 cells showed a significant (15.4% and 28.6% respectively) reduction of bone metastatic potential following intracardiac injection as determined by X-ray detection and by hematoxylin and eosin staining. Moreover, the expression of integrins αvβ3 and β3 was decreased in the BSP-silenced cells whereas ectopic BSP expression increased the integrins αvβ3 and β3 levels. These results together suggest that BSP silencing decreased the integrin αvβ3 and β3 levels, in turn inhibiting cell migration and invasion and decreasing the ability of the cells to metastasize to bone.
authors.affiliation: Department of Medical Research, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, Guangdong Province, China. jiew@tom.com
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Bing
authors.initials: B
authors.lastname: Xia
authors.forename: Chuanhong
authors.initials: C
authors.lastname: Yang
authors.forename: Huangwen
authors.initials: H
authors.lastname: Lai
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Chen
mesh_terms: D001859:Bone Neoplasms / Q000556:secondary*; D001943:Breast Neoplasms / Q000473:pathology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics*; D049109:Cell Proliferation; D002999:Clone Cells / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D020868:Gene Silencing; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D039661:Integrin beta3 / Q000378:metabolism; D058574:Integrin-Binding Sialoprotein / Q000172:deficiency* / Q000235:genetics* / Q000378:metabolism; D009361:Neoplasm Invasiveness; D013234:Stem Cells / Q000473:pathology
chemical_list: D039302:Integrin alphaVbeta3; D039661:Integrin beta3; D058574:Integrin-Binding Sialoprotein