title: Chemokine (C-C motif) ligand 2 mediates the prometastatic effect of dysadherin in human breast cancer cells.
abstract: Dysadherin, a cancer-associated membrane glycoprotein, down-regulates E-cadherin and promotes cancer metastasis. This study examined the role of dysadherin in breast cancer progression. Expression of dysadherin was found to be highest in breast cancer cell lines and tumors that lacked the estrogen receptor (ER). Knockdown of dysadherin caused increased association of E-cadherin with the actin cytoskeleton in breast cancer cell lines that expressed E-cadherin. However, knockdown of dysadherin could still suppress cell invasiveness in cells that had no functional E-cadherin, suggesting the existence of a novel mechanism of action. Global gene expression analysis identified chemokine (C-C motif) ligand 2 (CCL2) as the transcript most affected by dysadherin knockdown in MDA-MB-231 cells, and dysadherin was shown to regulate CCL2 expression in part through activation of the nuclear factor-kappaB pathway. The ability of dysadherin to promote tumor cell invasion in vitro was dependent on the establishment of a CCL2 autocrine loop, and CCL2 secreted by dysadherin-positive tumor cells also promoted endothelial cell migration in a paracrine fashion. Finally, experimental suppression of CCL2 in MDA-MB-231 cells reduced their ability to metastasize in vivo. This study shows that dysadherin has prometastatic effects that are independent of E-cadherin expression and that CCL2 could play an important role in mediating the prometastatic effect of dysadherin in ER-negative breast cancer.
authors.affiliation: Laboratory of Cell Regulation and Carcinogenesis, National Cancer Institute, Bethesda, MD 20892-5055, USA.
authors.forename: Jeong-Seok
authors.initials: JS
authors.lastname: Nam
authors.forename: Mi-Jin
authors.initials: MJ
authors.lastname: Kang
authors.forename: Adam M
authors.initials: AM
authors.lastname: Suchar
authors.forename: Takeshi
authors.initials: T
authors.lastname: Shimamura
authors.forename: Ethan A
authors.initials: EA
authors.lastname: Kohn
authors.forename: Aleksandra M
authors.initials: AM
authors.lastname: Michalowska
authors.forename: V Craig
authors.initials: VC
authors.lastname: Jordan
authors.forename: Setsuo
authors.initials: S
authors.lastname: Hirohashi
authors.forename: Lalage M
authors.initials: LM
authors.lastname: Wakefield
mesh_terms: D000199:Actins / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D015820:Cadherins / Q000378:metabolism; D045744:Cell Line, Tumor; D018932:Chemokine CCL2 / Q000378:metabolism*; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007473:Ion Channels; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D008840:Microfilament Proteins; D016328:NF-kappa B / Q000378:metabolism; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D011960:Receptors, Estrogen / Q000096:biosynthesis / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection; D015854:Up-Regulation
chemical_list: D000199:Actins; C111835:CCL2 protein, human; D015820:Cadherins; D018932:Chemokine CCL2; C451410:FXYD5 protein, human; D007473:Ion Channels; D008562:Membrane Glycoproteins; D008840:Microfilament Proteins; D016328:NF-kappa B; D009363:Neoplasm Proteins; D034741:RNA, Small Interfering; D011960:Receptors, Estrogen