High uniform fluid shear stress (FSS) is atheroprotective and preserves the endothelial phenotype and function through activation of downstream mediators such as MAPK7 (Erk5). Endothelial cells respond to FSS thanks to mechanotransduction. However, how the resulting signaling is integrated and resolved at the epigenetic level, remains elusive. We hypothesized that Polycomb methyltransferase EZH2 is involved in the effects of FSS in human endothelial cells. We showed that FSS decreases the expression of the Polycomb methyltransferase EZH2. Despite simultaneous activation of MAPK7, MAPK7 pathway does not directly influence the transcription of EZH2. Interestingly though, the knock down of EZH2 activates the protective MAPK7 signaling in endothelial cells, even in the absence of FSS. To understand the influence of the FSS-decreased expression of EZH2 on endothelial transcriptome, we performed RNA-seq and differential gene expression analysis. We identified candidate groups of genes dependent on both EZH2 and FSS. Among those, Gene Ontology overrepresentation analysis revealed highly significant enrichment of the cell cycle-related genes, suggesting changes in proliferation. Indeed, the depletion of EZH2 strongly inhibited endothelial proliferation, indicating cell cycle arrest. The concomitant decrease in CCNA expression suggests the transition of endothelial cells into a quiescent phenotype. Further bioinformatical analysis suggested TXNIP as a possible mediator between EZH2 and cell cycle-related gene network. Our data show that EZH2 is a FSS-responsive gene. Decreased EZH2 levels enhance the activation of the atheroprotective MAPK7 signaling. Decrease in EZH2 under FSS mediates the decrease in the expression of the network of cell cycle-related genes, which allows the cells to enter quiescence. EZH2 is therefore important for the protective effects of FSS in endothelium. Overall design: Puromycin-selected HUVEC (Human Umbilical Vein Endothelial Cells, Lonza, Switzerland) cells, expressing either scrambled control (SCR) or anti-EZH2 short-hairpin (shEZH2) constructs (at total 7 days after the first viral transduction), were used in FSS experiments (72h of control static culture or exposure to 20 dynes/cm2 of fluid shear stress, using Ibidi pump system (in µ-Slides I 0.4 Luer, Ibidi, Planegg/Martinsried, Germany)). Each replicate experiment consisted of viral transductions and puromycin selection of a separate HUVEC batch, followed by the FSS experiment. Two FSS experimental sets of the same HUVEC batch were run every time in parallel and lysed at the same end time point, one in RNAse-free conditions with RNA-Easy Mini Plus kit RLT Plus lysis buffer (QIAGEN, Venlo, The Netherlands), and one with RIPA buffer. The RIPA-lysates were analyzed with Western blotting and confirmed the complete (no protein present) knock-down of EZH2. From the RNA-lysates, RNA was isolated using the RNA-Easy Mini Plus kit (QIAGEN, Venlo, The Netherlands). High quality RNA samples (pre-assessed by Nanodrop measurements) were further processed in the Genome Analysis Facility of the University Medical Center Groningen. The RNA quality and integrity were verified using PerkinElmer Labchip GX with a cut-off value of 9 (scale 1 to 10, where 9 is very high quality RNA). RNA library was created in accordance with the TruSeqTM RNA Sample Preparation v2 Guide (Illumina, San Diego, CA, USA), using the PerkinElmer Sciclone liquid handler, resulting in 330bp cDNA fragments. The paired-end sequencing (100bp reads) was performed using the Illumina HiSeqTM 2500. (Quoted from the Materials and Methods of the related manuscript, with adjustments).
The decrease in histone methyltransferase EZH2 in response to fluid shear stress alters endothelial gene expression and promotes quiescence.
No sample metadata fields
View SamplesDmrt1 (doublesex and mab-3 related transcription factor 1) is a conserved transcriptional regulator of male differentiation required for testicular development in vertebrates. In mice of the 129Sv strain, loss of Dmrt1 causes a high incidence of teratomas. Mutant 129Sv germ cells undergo apparently normal differentiation up to embryonic day 13.5 (E13.5), but some cells fail to arrest mitosis and ectopically express pluripotency markers. Expression analysis and chromatin immunoprecipitation identified DMRT1 target genes whose misexpression may underly teratoma formation.
The DM domain protein DMRT1 is a dose-sensitive regulator of fetal germ cell proliferation and pluripotency.
Specimen part
View SamplesIn this study, zebrafish ZF4 and PAC2 cells were seeded in 0.5% or 1% FCS, respectively, and grown to 85% confluence and subsequently cultured for 24 hours without serum. Then they were treated with either medium without serum or medium with serum (ZF4 in 10% FCS and PAC2 in 15% FCS).After 6 hours, RNA was extracted from the cells and analyzed using the Affymetrix GeneChip Zebrafish Genome Array (GeneChip 430). There are 15502 oligonucleotide sets on each Affymetrix chip, 14895 of which can be linked to a UniGene assignment (Unigene data set 06-12-2005).
Genetic and transcriptome characterization of model zebrafish cell lines.
Cell line, Compound
View SamplesKruppel-like factors are a subclass of zinc finger transcription factors that play important roles in different aspects of cell growth, development, and differentiation. Our group have identified KLF13 as an essential transcription factor for the late expression of chemokine RANTES in T lymphocytes. However, very little is known about the role of KLF13 in T cells and other potential transcriptional targets. To address this, we sought to identify genes that are regulated by KLF13 in mouse T cells. Using microarray analysis, we compared gene expression in activated CD3+ T lymphocytes from wild type and Klf13-/- animals.
KLF13 cooperates with c-Maf to regulate IL-4 expression in CD4+ T cells.
Sex, Age, Specimen part
View SamplesDerivation and expansion of human umbilical cord blood-derived endothelial colony forming cells under serum-free conditions - a transcriptome analysis.
Optimization of the culturing conditions of human umbilical cord blood-derived endothelial colony-forming cells under xeno-free conditions applying a transcriptomic approach.
Specimen part
View SamplesMemory-like T cells are a subset of thymic cells that acquire effector function through the maturation process rather than interaction with specific antigen. Disruption of genes encoding T cell signaling proteins or transcription factors have provided insights into the differentiation of such cells. We show here that in BALB/c but not C57BL/6 mice, a large portion of thymic CD4-CD8+ T cells exhibit a memory-like phenotype. In BALB/c mice, IL-4 secreted by invariant natural killer T (iNKT) cells is both essential and sufficient for the generation of memory-like T cells. In C57BL/6 mice, iNKT cells are less abundant, producing IL-4 that is insufficient to induce thymic memory-like CD8+ T cells. BALB/c mice deficient in the transcription factor Kruppel-like factor (KLF) 13 have comparable numbers of iNKT cells to C57BL/6 mice and extremely low levels of thymic memory-like CD8+ T cells. This work documents the dramatic impact of a small number of KLF13-dependent iNKT cells.
KLF13 sustains thymic memory-like CD8(+) T cells in BALB/c mice by regulating IL-4-generating invariant natural killer T cells.
Specimen part
View SamplesPancreatic cancer is an aggressive malignancy, often diagnosed at metastatic stages. Several studies have implicated systemic factors, such as extracellular vesicle release and myeloid cell expansion, in the establishment of pre-metastatic niches in cancer. The Rab27a GTPase is overexpressed in advanced cancers, can regulate vesicle trafficking, and has been previously linked to non-cell autonomous control of tumor growth and metastasis, however, the role of Rab27a itself in the metastatic propensity of pancreatic cancer is not well understood. Here, we have established a model to study how Rab27a directs formation of the pre-metastatic niche. Loss of Rab27a in pancreatic cancer cells did not decrease tumor growth in vivo, but resulted in altered systemic myeloid cell expansion, both in the primary tumors and at the distant organ sites. In metastasis assays, loss of Rab27a expression in tumor cells injected into circulation compromised efficient outgrowth of metastatic lesions. However, Rab27a knockdown cells had an unexpected advantage at initial steps of metastatic seeding, suggesting that Rab27a may alter cell-autonomous invasive properties of the tumor cells. Gene expression analysis of gene expression revealed that downregulation of Rab27a increased expression of genes involved in epithelial-to-mesenchymal transition pathways, consistent with our findings that primary tumors arising from Rab27a knockdown cells were more invasive. Overall, these data reveal that Rab27a can play divergent roles in regulating pro-metastatic propensity of pancreatic cancer cells: by generating pro-metastatic environment at the distant organ sites, and by suppressing invasive properties of the cancer cells.
Rab27a plays a dual role in metastatic propensity of pancreatic cancer.
Cell line
View SamplesBackground: Macrophages are important cells in pathogenesis of obstructive lung diseases including asthma and chronic obstructive pulmonary disease (COPD). The aim of the study was a multivariate, genetic, comparative analysis of macrophages from patients with asthma and COPD.
Genetic characterization of macrophages from induced sputum of patients with asthma and chronic obstructive pulmonary disease.
Specimen part, Disease
View SamplesIPH-926 is an anticancer drug-resistant tumor cell line derived from a chemo-refractory human infiltrating lobular breast cancer (ILBC). IPH-926 ILBC cells were subjected to gene expression profiling using an Affymetrix HG U133 Plus 2.0 array.
ABCB1/MDR1 contributes to the anticancer drug-resistant phenotype of IPH-926 human lobular breast cancer cells.
Specimen part, Cell line
View SamplesGene expression profile based classification of colonic diseases are suitable for identification of diagnostic mRNA expression patterns which can establish the basis of a new molecular biological diagnostic method
Diagnostic mRNA expression patterns of inflamed, benign, and malignant colorectal biopsy specimen and their correlation with peripheral blood results.
No sample metadata fields
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