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Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer

VEGF plays a central role in angiogenesis in cancer. Non-small cell lung cancer (NSCLC) tumors have increased microvascular density, localized hypoxia, and high VEGF expression levels; however, there is a lack of understanding of how oncogenic and tumor microenvironment changes such as hypoxia lead...

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Autores principales: Deacon, Karl, Onion, David, Kumari, Rajendra, Watson, Susan A., Knox, Alan J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Society for Biochemistry and Molecular Biology 2012
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3501049/
https://www.ncbi.nlm.nih.gov/pubmed/22992725
http://dx.doi.org/10.1074/jbc.M112.397042
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author Deacon, Karl
Onion, David
Kumari, Rajendra
Watson, Susan A.
Knox, Alan J.
author_facet Deacon, Karl
Onion, David
Kumari, Rajendra
Watson, Susan A.
Knox, Alan J.
author_sort Deacon, Karl
collection PubMed
description VEGF plays a central role in angiogenesis in cancer. Non-small cell lung cancer (NSCLC) tumors have increased microvascular density, localized hypoxia, and high VEGF expression levels; however, there is a lack of understanding of how oncogenic and tumor microenvironment changes such as hypoxia lead to greater VEGF expression in lung and other cancers. We show that NSCLC cells secreted higher levels of VEGF than normal airway epithelial cells. Actinomycin D inhibited all NSCLC VEGF secretion, and VEGF minimal promoter-luciferase reporter constructs were constitutively active until the last 85 base pairs before the transcription start site containing three SP-1 transcription factor-binding sites; mutation of these VEGF promoter SP-1-binding sites eliminated VEGF promoter activity. Furthermore, dominant negative SP-1, mithramycin A, and SP-1 shRNA decreased VEGF promoter activity, whereas overexpression of SP-1 increased VEGF promoter activity. Chromatin immunoprecipitation assays demonstrated SP-1, p300, and PCA/F histone acetyltransferase binding and histone H4 hyperacetylation at the VEGF promoter in NSCLC cells. Cultured NSCLC cells expressed higher levels of SP-1 protein than normal airway epithelial cells, and double-fluorescence immunohistochemistry showed a strong correlation between SP-1 and VEGF in human NSCLC tumors. In addition, hypoxia-driven VEGF expression in NSCLC cells was SP-1-dependent, with hypoxia increasing SP-1 activity and binding to the VEGF promoter. These studies are the first to demonstrate that overexpression of SP-1 plays a central role in hypoxia-induced VEGF secretion.
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spelling pubmed-35010492012-11-19 Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer Deacon, Karl Onion, David Kumari, Rajendra Watson, Susan A. Knox, Alan J. J Biol Chem Gene Regulation VEGF plays a central role in angiogenesis in cancer. Non-small cell lung cancer (NSCLC) tumors have increased microvascular density, localized hypoxia, and high VEGF expression levels; however, there is a lack of understanding of how oncogenic and tumor microenvironment changes such as hypoxia lead to greater VEGF expression in lung and other cancers. We show that NSCLC cells secreted higher levels of VEGF than normal airway epithelial cells. Actinomycin D inhibited all NSCLC VEGF secretion, and VEGF minimal promoter-luciferase reporter constructs were constitutively active until the last 85 base pairs before the transcription start site containing three SP-1 transcription factor-binding sites; mutation of these VEGF promoter SP-1-binding sites eliminated VEGF promoter activity. Furthermore, dominant negative SP-1, mithramycin A, and SP-1 shRNA decreased VEGF promoter activity, whereas overexpression of SP-1 increased VEGF promoter activity. Chromatin immunoprecipitation assays demonstrated SP-1, p300, and PCA/F histone acetyltransferase binding and histone H4 hyperacetylation at the VEGF promoter in NSCLC cells. Cultured NSCLC cells expressed higher levels of SP-1 protein than normal airway epithelial cells, and double-fluorescence immunohistochemistry showed a strong correlation between SP-1 and VEGF in human NSCLC tumors. In addition, hypoxia-driven VEGF expression in NSCLC cells was SP-1-dependent, with hypoxia increasing SP-1 activity and binding to the VEGF promoter. These studies are the first to demonstrate that overexpression of SP-1 plays a central role in hypoxia-induced VEGF secretion. American Society for Biochemistry and Molecular Biology 2012-11-16 2012-09-19 /pmc/articles/PMC3501049/ /pubmed/22992725 http://dx.doi.org/10.1074/jbc.M112.397042 Text en © 2012 by The American Society for Biochemistry and Molecular Biology, Inc. Author's Choice—Final version full access. Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) applies to Author Choice Articles
spellingShingle Gene Regulation
Deacon, Karl
Onion, David
Kumari, Rajendra
Watson, Susan A.
Knox, Alan J.
Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer
title Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer
title_full Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer
title_fullStr Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer
title_full_unstemmed Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer
title_short Elevated SP-1 Transcription Factor Expression and Activity Drives Basal and Hypoxia-induced Vascular Endothelial Growth Factor (VEGF) Expression in Non-Small Cell Lung Cancer
title_sort elevated sp-1 transcription factor expression and activity drives basal and hypoxia-induced vascular endothelial growth factor (vegf) expression in non-small cell lung cancer
topic Gene Regulation
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3501049/
https://www.ncbi.nlm.nih.gov/pubmed/22992725
http://dx.doi.org/10.1074/jbc.M112.397042
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