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CCAAT/enhancer binding protein ? (C/EBP?) isoforms as transcriptional regulators of the pro-invasive CDH3/P-cadherin gene in human breast cancer cells.

ABSTRACT: P-cadherin is a cell-cell adhesion molecule codified by the CDH3 gene, which expression is highly associated with undifferentiated cells in normal adult epithelial tissues, as well as with poorly differentiated carcinomas. In breast cancer, P-cadherin is frequently overexpressed in high-grade tumours and is a well-established indicator of aggressive tumour behaviour and poor patient prognosis. However, till now, the mechanisms controlling CDH3 gene activation have been poorly explored. Since we recently described the existence of several CCAAT/Enhancer Binding Protein ? (C/EBP?) transcription factor binding sites at the CDH3 promoter, the aim of this study was to assess if the distinct C/EBP? isoforms were directly involved in the transcriptional activation of the CDH3 gene in breast cancer cells. DNA-protein interactions, mutation analysis and luciferase reporter assay studies have been performed. We demonstrated that C/EBP? is co-expressed with P-cadherin in breast cancer cells and all the three isoforms function as transcriptional regulators of the CDH3 gene, directly interacting with specific regions of its promoter. Interestingly, this transcriptional activation was only reflected at the P-cadherin protein level concerning the LIP isoform. Taken together, our data show that CDH3 is a newly defined transcriptional target gene of C/EBP? isoforms in breast cancer, and we also identified the binding sites that are relevant for this activation.

SUBMITTER: Albergaria A

PROVIDER: S-EPMC3566012 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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CCAAT/enhancer binding protein β (C/EBPβ) isoforms as transcriptional regulators of the pro-invasive CDH3/P-cadherin gene in human breast cancer cells.

Albergaria André A Resende Carlos C Nobre Ana Rita AR Ribeiro Ana Sofia AS Sousa Bárbara B Machado José Carlos JC Seruca Raquel R Paredes Joana J Schmitt Fernando F Schmitt Fernando F

PloS one 20130206 2

P-cadherin is a cell-cell adhesion molecule codified by the CDH3 gene, which expression is highly associated with undifferentiated cells in normal adult epithelial tissues, as well as with poorly differentiated carcinomas. In breast cancer, P-cadherin is frequently overexpressed in high-grade tumours and is a well-established indicator of aggressive tumour behaviour and poor patient prognosis. However, till now, the mechanisms controlling CDH3 gene activation have been poorly explored. Since we ...[more]

PMID: 23405208

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Dataset Information

CCAAT/enhancer binding protein ? (C/EBP?) isoforms as transcriptional regulators of the pro-invasive CDH3/P-cadherin gene in human breast cancer cells.

Publications

CCAAT/enhancer binding protein β (C/EBPβ) isoforms as transcriptional regulators of the pro-invasive CDH3/P-cadherin gene in human breast cancer cells.

Similar Datasets

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