TY - JOUR
T1 - Wnt-5a-CKlα signaling promotes β-catenin/E-cadherin complex formation and intercellular adhesion in human breast epithelial cells
AU - Medrek, Catharina
AU - Landberg, Göran
AU - Andersson, Tommy
AU - Leandersson, Karin
PY - 2009/4/17
Y1 - 2009/4/17
N2 - Wnt-5a is a non-transforming Wnt protein that is implicated in cell polarity, adhesion, and motility. We have previously shown that low expression of Wnt-5a is a predictor of shorter disease-free survival in human breast cancer. Here, we investigated whether β-catenin/ E-cadherin-mediated cell-cell adhesion was affected by loss of Wnt-5a in breast carcinomas, thereby promoting a metastatic behavior of the tumor. We show that Wnt-5a stimulation of human breast epithelial cells leads to an increased Ca2+-dependent cell-cell adhesion. Furthermore, Wnt-5a/casein kinase Iα (CKIα)-specific Ser-45 phosphorylation of β-catenin is associated with an increased complex formation of β-catenin/E-cadherin. Mutation of Ser-45 decreases the β-catenin/E-cadherin association. Also, the inhibitory effect of Wnt-5a on breast epithelial cell invasion is reduced upon mutation of β-catenin-Ser-45. The Wnt-5a-CKIα-induced Ser-45 phosphorylation does not lead to degradation of β-catenin. Finally we show that human breast cancers lacking Wnt-5a protein have a significantly lower level of membrane-associated β-catenin. Down-regulation of Wnt-5a expression and subsequent reduction of membrane-associated β-catenin in invasive breast cancer, can therefore contribute to a decreased cell-cell adhesion and increased motility resulting in a higher probability for metastatic disease. © 2009 by The American Society for Biochemistry and Molecular Biology, Inc.
AB - Wnt-5a is a non-transforming Wnt protein that is implicated in cell polarity, adhesion, and motility. We have previously shown that low expression of Wnt-5a is a predictor of shorter disease-free survival in human breast cancer. Here, we investigated whether β-catenin/ E-cadherin-mediated cell-cell adhesion was affected by loss of Wnt-5a in breast carcinomas, thereby promoting a metastatic behavior of the tumor. We show that Wnt-5a stimulation of human breast epithelial cells leads to an increased Ca2+-dependent cell-cell adhesion. Furthermore, Wnt-5a/casein kinase Iα (CKIα)-specific Ser-45 phosphorylation of β-catenin is associated with an increased complex formation of β-catenin/E-cadherin. Mutation of Ser-45 decreases the β-catenin/E-cadherin association. Also, the inhibitory effect of Wnt-5a on breast epithelial cell invasion is reduced upon mutation of β-catenin-Ser-45. The Wnt-5a-CKIα-induced Ser-45 phosphorylation does not lead to degradation of β-catenin. Finally we show that human breast cancers lacking Wnt-5a protein have a significantly lower level of membrane-associated β-catenin. Down-regulation of Wnt-5a expression and subsequent reduction of membrane-associated β-catenin in invasive breast cancer, can therefore contribute to a decreased cell-cell adhesion and increased motility resulting in a higher probability for metastatic disease. © 2009 by The American Society for Biochemistry and Molecular Biology, Inc.
U2 - 10.1074/jbc.M804923200
DO - 10.1074/jbc.M804923200
M3 - Article
C2 - 19244247
SN - 1083-351X
VL - 284
SP - 10968
EP - 10979
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 16
ER -