TY - JOUR
T1 - Endothelin-1 promotes epithelial-to-mesenchymal transition in human ovarian cancer cells
AU - Rosanò, Laura
AU - Spinella, Francesca
AU - Di Castro, Valeriana
AU - Nicotra, Maria Rita
AU - Dedhar, Shoukat
AU - Garcia De Herreros, Antonio
AU - Natali, Pier Giorgio
AU - Bagnato, Anna
PY - 2005/12/15
Y1 - 2005/12/15
N2 - Despite considerable efforts to improve early detection and advances in chemotherapy, metastatic relapses remain a major challenge in the management of ovarian cancer. The endothelin A receptor (ETAR)/endothelin-1 (ET-1) axis has been shown to have a significant role in ovarian carcinoma by promoting tumorigenesis. Here we show that the ET-1/ETAR autocrine pathway drives epithelial-to-mesenchymal transition (EMT) in ovarian tumor cells by inducing a fibroblastoid and invasive phenotype, down-regulation of E-cadherin, increased levels of β-catenin, Snail, and other mesenchymal markers, and suppression of E-cadherin promoter activity. Activation of ETAR by ET-1 triggers an integrin-linked kinase (ILK)-mediated signaling pathway leading to glycogen synthase kinase-3β (GSK-3β) inhibition, Snail and β-catenin stabilization, and regulation of transcriptional programs that control EMT. Transfection of dominant negative ILK or exposure to an ILK inhibitor suppresses the ET-1-induced phosphorylation of GSK-3β as well as Snail and β-catenin protein stability, activity, and invasiveness, indicating that ET-1/ETAR-induced EMT-promoting effects depend on ILK. ETAR blockade by specific antagonists or reduction by ET AR RNA interference reverses EMT and cell invasion by inhibiting autocrine signaling pathways. In ovarian carcinoma xenografts, ABT-627, a specific ETAR antagonist, suppresses EMT determinants and tumor growth. In human ovarian cancers, ETAR expression is associated with E-cadherin downregulation, N-cadherin expression, and tumor grade. Collectively, these findings provide evidence of a critical role for the ET-1/ETAR axis during distinct steps of ovarian carcinoma progression and identify novel targets of therapeutic intervention.
AB - Despite considerable efforts to improve early detection and advances in chemotherapy, metastatic relapses remain a major challenge in the management of ovarian cancer. The endothelin A receptor (ETAR)/endothelin-1 (ET-1) axis has been shown to have a significant role in ovarian carcinoma by promoting tumorigenesis. Here we show that the ET-1/ETAR autocrine pathway drives epithelial-to-mesenchymal transition (EMT) in ovarian tumor cells by inducing a fibroblastoid and invasive phenotype, down-regulation of E-cadherin, increased levels of β-catenin, Snail, and other mesenchymal markers, and suppression of E-cadherin promoter activity. Activation of ETAR by ET-1 triggers an integrin-linked kinase (ILK)-mediated signaling pathway leading to glycogen synthase kinase-3β (GSK-3β) inhibition, Snail and β-catenin stabilization, and regulation of transcriptional programs that control EMT. Transfection of dominant negative ILK or exposure to an ILK inhibitor suppresses the ET-1-induced phosphorylation of GSK-3β as well as Snail and β-catenin protein stability, activity, and invasiveness, indicating that ET-1/ETAR-induced EMT-promoting effects depend on ILK. ETAR blockade by specific antagonists or reduction by ET AR RNA interference reverses EMT and cell invasion by inhibiting autocrine signaling pathways. In ovarian carcinoma xenografts, ABT-627, a specific ETAR antagonist, suppresses EMT determinants and tumor growth. In human ovarian cancers, ETAR expression is associated with E-cadherin downregulation, N-cadherin expression, and tumor grade. Collectively, these findings provide evidence of a critical role for the ET-1/ETAR axis during distinct steps of ovarian carcinoma progression and identify novel targets of therapeutic intervention.
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U2 - 10.1158/0008-5472.CAN-05-2123
DO - 10.1158/0008-5472.CAN-05-2123
M3 - Article
C2 - 16357176
AN - SCOPUS:29144495415
VL - 65
SP - 11649
EP - 11657
JO - Journal of Cancer Research
JF - Journal of Cancer Research
SN - 0008-5472
IS - 24
ER -