Overexpression of CD9 in Human Breast Cancer Cells Promotes the Development of Bone Metastases

• Published in: Anticancer research Vol. 32; no. 12; pp. 5211 - 5220
• Main Authors: KISCHEL, Philippe, BELLAHCENE, Akeila, DEUX, Blandine, LAMOUR, Virginie, DOBSON, Rowan, DE PAUW, Edwin, CLEZARDIN, Philippe, CASTRONOVO, Vincent
• Format: Journal Article Web Resource
• Language: English
• Published: Attiki International Institute of Anticancer Research 01.12.2012
• Subjects: Aged; Aged, 80 and over; Animals; Antigens, CD9/biosynthesis; Biochemistry, biophysics & molecular biology; Biochimie, biophysique & biologie moléculaire; Biological and medical sciences; Biomarkers, Tumor - biosynthesis; Bone Neoplasms - metabolism; Bone Neoplasms - secondary; Bone Neoplasms/metabolism/secondary; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Breast Neoplasms/metabolism/pathology; Cell Line, Tumor; Female; Gynecology. Andrology. Obstetrics; Human health sciences; Humans; Immunoblotting; Life sciences; Mammary gland diseases; Medical sciences; Mice; Mice, Inbred BALB C; Mice, Nude; Middle Aged; Oncologie; Oncology; Sciences de la santé humaine; Sciences du vivant; Tetraspanin-29 - biosynthesis; Tumor Markers, Biological/biosynthesis; Tumors; Up-Regulation; Human; Cell proliferation; Membrane protein; Breast disease; Breast tumor; Diseases of the osteoarticular system; B02 cells; Gene overexpression; Breast cancer; cancer cells; Malignant tumor; Carcinogenesis; Mammary gland diseases; Bone metastasis; osteotropism; Cancerology; membrane proteins; Tumor cell; MDA-MB-231; Cancer; Tetraspanin
• ISSN: 0250-7005; 1791-7530; 1791-7530

Bone is a preferred target for circulating metastatic breast cancer cells. We found that the CD9 protein was up-regulated in the B02 osteotropic cell line, derived from the aggressive parental MDA-MB-231 breast cancer cell line. Here, we investigated the putative relationship between CD9 expression and the osteotropic phenotype. Overexpression of CD9 was analyzed by immunoblotting in different cell lines. Immunohistochemistry was used to assess CD9 expression in primary tumors and metastatic lesions. In vivo experiments were conducted in mice using a monoclonal antibody against CD9. CD9 overexpression was confirmed in osteotropic cells. CD9 was significantly overexpressed in bone metastases versus primary tumors and visceral metastatic lesions. Finally, in vivo experiments showed that an antibody against CD9 delays homing of B02 cells in bone marrow, slowing down bone destruction. Our study reveals a potential implication of CD9 in the formation of bony metastases from breast cancer cells.