title: AND-34/BCAR3 regulates adhesion-dependent p130Cas serine phosphorylation and breast cancer cell growth pattern.
abstract: NSP protein family members associate with p130Cas, a focal adhesion adapter protein best known as a Src substrate that integrates adhesion-related signaling. Over-expression of AND-34/BCAR3/NSP2 (BCAR3), but not NSP1 or NSP3, induces anti-estrogen resistance in human breast cancer cell lines. BCAR3 over-expression in epithelial MCF-7 cells augments levels of a phosphorylated p130Cas species that migrates more slowly on SDS-PAGE while NSP1 and NSP3 induce modest or no phosphorylation, respectively. Conversely, reduction in BCAR3 expression in mesenchymal MDA-231 cells by inducible shRNA results in loss of such p130Cas phosphorylation. Replacement of NSP3's serine/proline-rich domain with that of AND-34/BCAR3 instills the ability to induce p130Cas phosphorylation. Phospho-amino acid analysis demonstrates that BCAR3 induces p130Cas serine phosphorylation. Mass spectrometry identified phosphorylation at p130Cas serines 139, 437 and 639. p130Cas serine phosphorylation accumulates for several hours after adhesion of MDA-231 cells to fibronectin and is dependent upon BCAR3 expression. BCAR3 knockdown alters p130Cas localization and converts MDA-231 growth to an epithelioid pattern characterized by striking cohesiveness and lack of cellular projections at colony borders. These studies demonstrate that BCAR3 regulates p130Cas serine phosphorylation that is adhesion-dependent, temporally distinct from previously well-characterized rapid Fak and Src kinase-mediated p130Cas tyrosine phosphorylation and that correlates with invasive phenotype.
authors.affiliation: Department of Medicine, Section of Hematology and Oncology, Boston Medical Center, Boston, Massachusetts 02118, USA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Makkinje
authors.forename: Richard I
authors.initials: RI
authors.lastname: Near
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Infusini
authors.forename: Pierre
authors.initials: P
authors.lastname: Vanden Borre
authors.forename: Alexander
authors.initials: A
authors.lastname: Bloom
authors.forename: Dongpo
authors.initials: D
authors.lastname: Cai
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Costello
authors.forename: Adam
authors.initials: A
authors.lastname: Lerner
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002448:Cell Adhesion; D050719:Crk-Associated Substrate Protein / Q000378:metabolism*; D005260:Female; D055785:Gene Knockdown Techniques; D020662:Guanine Nucleotide Exchange Factors; D006801:Humans; D008969:Molecular Sequence Data; D010766:Phosphorylation; D034622:RNA Interference; D012694:Serine / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D018909:src Homology Domains
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C118588:BCAR3 protein, human; D050719:Crk-Associated Substrate Protein; D020662:Guanine Nucleotide Exchange Factors; C118587:SH2D3A protein, human; C118589:SH2D3C protein, human; D012694:Serine