title: The role of multicellular aggregation in the survival of ErbB2-positive breast cancer cells during extracellular matrix detachment.
abstract: The metastasis of cancer cells from the site of the primary tumor to distant sites in the body represents the most deadly manifestation of cancer. In order for metastasis to occur, cancer cells need to evade anoikis, which is defined as apoptosis caused by loss of attachment to extracellular matrix (ECM). Signaling from ErbB2 has previously been linked to the evasion of anoikis in breast cancer cells but the precise molecular mechanisms by which ErbB2 blocks anoikis have yet to be unveiled. In this study, we have identified a novel mechanism by which anoikis is inhibited in ErbB2-expressing cells: multicellular aggregation during ECM-detachment. Our data demonstrate that disruption of aggregation in ErbB2-positive cells is sufficient to induce anoikis and that this anoikis inhibition is a result of aggregation-induced stabilization of EGFR and consequent ERK/MAPK survival signaling. Furthermore, these data suggest that ECM-detached ErbB2-expressing cells may be uniquely susceptible to targeted therapy against EGFR and that this sensitivity could be exploited for specific elimination of ECM-detached cancer cells.
authors: From the Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556.
authors: Raju R
authors: RR
authors: Rayavarapu
authors: From the Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556.
authors: Brendan
authors: B
authors: Heiden
authors: From the Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556.
authors: Nicholas
authors: N
authors: Pagani
authors: From the Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556.
authors: Melissa M
authors: MM
authors: Shaw
authors: From the Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556.
authors: Sydney
authors: S
authors: Shuff
authors: From the Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556.
authors: Siyuan
authors: S
authors: Zhang
authors: From the Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556 zschafe1@nd.edu.
authors: Zachary T
authors: ZT
authors: Schafer
mesh_terms: D001943:Breast Neoplasms / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D005109:Extracellular Matrix / Q000378:metabolism / Q000473:pathology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D006801:Humans; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D048049:Extracellular Signal-Regulated MAP Kinases; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: aggregation; anoikis; breast cancer; epidermal growth factor receptor (EGFR); extracellular matrix; metastasis