Zoledronic acid reverses the epithelial-mesenchymal transition and inhibits self-renewal of breast cancer cells through inactivation of NF-κB.
Mol Cancer Ther
; 12(7): 1356-66, 2013 Jul.
Article
em En
| MEDLINE
| ID: mdl-23619300
ABSTRACT
Zoledronic acid, a third-generation bisphosphonate, has been shown to reduce cell migration, invasion, and metastasis. However, the effects of zoledronic acid on the epithelial-mesenchymal transition (EMT), a cellular process essential to the metastatic cascade, remain unclear. Therefore, the effects of zoledronic acid on EMT, using triple-negative breast cancer (TNBC) cells as a model system, were examined in more detail. Zoledronic acid treatment decreased the expression of mesenchymal markers, N-cadherin, Twist, and Snail, and subsequently upregulated expression of E-cadherin. Zoledronic acid also inhibited cell viability, induced cell-cycle arrest, and decreased the proliferative capacity of TNBC, suggesting that zoledronic acid inhibits viability through reduction of cell proliferation. As EMT has been linked to acquisition of a self-renewal phenotype, the effects of zoledronic acid on self-renewal in TNBC were also studied. Treatment with zoledronic acid decreased expression of self-renewal proteins, BMI-1 and Oct-4, and both prevented and eliminated mammosphere formation. To understand the mechanism of these results, the effect of zoledronic acid on established EMT regulator NF-κB was investigated. Zoledronic acid inhibited phosphorylation of RelA, the active subunit of NF-κB, at serine 536 and modulated RelA subcellular localization. Treatment with zoledronic acid reduced RelA binding to the Twist promoter, providing a direct link between inactivation of NF-κB signaling and loss of EMT transcription factor gene expression. Binding of Twist to the BMI-1 promoter was also decreased, correlating modulation of EMT to decreased self-renewal. On the basis of these results, it is proposed that through inactivation of NF-κB, zoledronic acid reverses EMT, which leads to a decrease in self-renewal.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Neoplasias da Mama
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NF-kappa B
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Difosfonatos
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Transição Epitelial-Mesenquimal
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Imidazóis
Tipo de estudo:
Prognostic_studies
Limite:
Female
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Humans
Idioma:
En
Revista:
Mol Cancer Ther
Ano de publicação:
2013
Tipo de documento:
Article