Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Gene expression profiling of Human Umbilical Vein Endothelial Cells (HUVEC) after treatment with Erg or control antisense (GeneBloc)

ABSTRACT: The endothelial transcription factor Erg (Ets Related Gene) plays an important role in homeostasis and angiogenesis by regulating many endothelial functions including survival and junction stability. Here we show that Erg regulates endothelial cell migration. Transcriptome profiling of Erg-deficient endothelial cells (EC) identified 80 genes involved in cell migration as candidate Erg targets, including regulators of the Rho GTPases. Inhibition of Erg expression in human umbilical vein endothelial cells (HUVEC) resulted in decreased migration in vitro, whilst Erg over-expression using adenovirus caused increased migration. Live-cell imaging of Erg-deficient HUVEC showed a reduction in lamellipodia, in line with decreased motility. Both actin and tubulin cytoskeletons were disrupted in Erg-deficient EC, with a dramatic increase in tubulin acetylation. Amongst the most significant microarray hit was the cytosolic histone deacetylase (HDAC)-6, a regulator of cell migration. Rescue experiments confirmed that HDAC6 mediates the Erg-dependent regulation of tubulin acetylation and actin localization. The functional role of Erg in EC was studied by gene expressing profiling using three separate HUVEC isolates treated with either control antisense or Erg-specific antisense for 24 or 48 hours.

ORGANISM(S): Homo sapiens

SUBMITTER: Graeme Birdsey

PROVIDER: E-GEOD-32984 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

The transcription factor Erg regulates expression of histone deacetylase 6 and multiple pathways involved in endothelial cell migration and angiogenesis.

Birdsey Graeme M GM Dryden Nicola H NH Shah Aarti V AV Hannah Rebecca R Hall Matthew D MD Haskard Dorian O DO Parsons Maddy M Mason Justin C JC Zvelebil Marketa M Gottgens Berthold B Ridley Anne J AJ Randi Anna M AM

Blood 20111123 3

The endothelial ETS transcription factor Erg plays an important role in homeostasis and angiogenesis by regulating many endothelial functions including survival and junction stability. Here we show that Erg regulates endothelial cell (EC) migration. Transcriptome profiling of Erg-deficient ECs identified ∼ 80 genes involved in cell migration as candidate Erg targets, including many regulators of Rho- GTPases. Inhibition of Erg expression in HUVECs resulted in decreased migration in vitro, while ...[more]

PMID: 22117042

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Project description:Chronic lymphocytic leukemic B cells (CLL) reside in close contact with activated endothelial cells (EC) in infiltrated tissues. Here, we investigated the interactions between EC and CLL cells, highlighting molecular networks involved in this cellular crosstalk. We co-cultured purified CLL cells on HUVEC monolayer (HC) or in medium alone. We found that EC protected CLL from spontaneous apoptosis. A 2.2-fold increase in relative viability in IGHV mutated CLL and a 6.1-fold increase in IGHV unmutated CLL was detected in co-culture. Moreover, the endothelial cell layer decreased the in vitro sensitivity of CLL cells to Fludarabine-induced apoptosis. Physical contact with EC is essential for protection to apoptosis. The insertion of a microporous membrane or blocking adhesion with anti-CD106 and anti-CD18 antibodies determined the complete abrogation of apoptosis protection. On the other hand, a reduction of apoptosis was measured in CLL cells cultured with conditioned medium collected from HC, implying that survival is partially mediated by soluble factors. Overall 1944 genes were modulated in CLL by co-culture. The EC contact seem to determine on CLL a kind of microenvironmental-driven angiogenic switch, improve the secretion of cytokines regulating tissue elements such as stromal cells and macrophages and also increase anti-apoptotic molecules. Our study support the line of evidence indicating endothelial cells as a major player in the CLL-infiltrated microenvironments are able to create a vicious cycle of cooperation that strongly sustains leukemic cell survival, protects CLL from drug-induced apoptosis and widely modifies CLL phenotype. Large-scale gene expression profiling (GEP) was performed on total RNA extracted from purified CD19+ cells isolated from 9 individual CLL patients which were separated in 3 experimental subsets: (i) freshly isolated cells (CLL baseline), (ii) CLL cells cultured in medium alone for 48 hours (CLL only) and (iii) CLL cells co-cultured 48h on HUVEC layer (CLL HC).

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Dataset Information

Gene expression profiling of Human Umbilical Vein Endothelial Cells (HUVEC) after treatment with Erg or control antisense (GeneBloc)

Publications

The transcription factor Erg regulates expression of histone deacetylase 6 and multiple pathways involved in endothelial cell migration and angiogenesis.

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