title: Disruption of laminin-integrin-CD151-focal adhesion kinase axis sensitizes breast cancer cells to ErbB2 antagonists.
abstract: Resistance to anti-ErbB2 agents is a significant problem in the treatment of human ErbB2+ breast cancers. We show here that adhesion of human ErbB2+ breast cancer cells to basement membrane laminin-5 provides substantial resistance to trastuzumab and lapatinib, agents that respectively target the extracellular and kinase domains of ErbB2. Knockdown of laminin-binding integrins (alpha6beta4, alpha3beta1) or associated tetraspanin protein CD151 reversed laminin-5 resistance and sensitized ErbB2+ cells to trastuzumab and lapatinib. CD151 knockdown, together with trastuzumab treatment, inhibited ErbB2 activation and downstream signaling through Akt, Erk1/2, and focal adhesion kinase (FAK). Hence, ErbB2 function in mammary tumor cells is promoted by integrin-mediated adhesion to laminin-5, with strong support by CD151, leading to signaling through FAK. Consequently, removal or inhibition of any of these components (laminin-5, integrin, CD151, FAK) markedly sensitizes cells to anti-ErbB2 agents. These new insights should be useful when devising strategies for overcoming drug resistance in ErbB2+ cancers.
authors.affiliation: Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute and Harvard Medical School, University of Massachusetts, Boston, Massachusetts, USA. xya222@uky.edu
authors.forename: Xiuwei H
authors.initials: XH
authors.lastname: Yang
authors.forename: Ludmila M
authors.initials: LM
authors.lastname: Flores
authors.forename: Qinglin
authors.initials: Q
authors.lastname: Li
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Zhou
authors.forename: Fenghui
authors.initials: F
authors.lastname: Xu
authors.forename: Ian E
authors.initials: IE
authors.lastname: Krop
authors.forename: Martin E
authors.initials: ME
authors.lastname: Hemler
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D015703:Antigens, CD / Q000378:metabolism*; D000970:Antineoplastic Agents / Q000494:pharmacology; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D045744:Cell Line, Tumor; D004357:Drug Synergism; D004789:Enzyme Activation; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism*; D006801:Humans; D039201:Integrin alpha3beta1 / Q000378:metabolism; D039161:Integrin alpha6beta4 / Q000378:metabolism; D000077341:Lapatinib; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011799:Quinazolines / Q000494:pharmacology; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors*; D015398:Signal Transduction; D060185:Tetraspanin 24; D000068878:Trastuzumab; D000097794:Kalinin
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D015703:Antigens, CD; D000970:Antineoplastic Agents; D015815:Cell Adhesion Molecules; D051416:Focal Adhesion Protein-Tyrosine Kinases; D039201:Integrin alpha3beta1; D039161:Integrin alpha6beta4; D000077341:Lapatinib; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D018719:Erb-b2 Receptor Tyrosine Kinases; D060185:Tetraspanin 24; D000068878:Trastuzumab; D000097794:Kalinin; C554715:CD151 protein, human