Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

HOB Transcriptome after HUVEC-Cocultivation

ABSTRACT: Vascularization represents an important issue in bone development, fracture healing and engineering of artificial bone tissue. In the context of bone tissue engineering, it was shown that coimplantation of human primary umbilical vein endothelial cells (HUVECs) and human osteoblasts (hOBs) results in the formation of functional blood vessels and enhanced bone regeneration. Implanted endothelial cells do not only contribute to blood vessel formation, but also support proliferation, cell survival and osteogenic differentiation of coimplanted hOBs. These effects are partially mediated by direct heterotypic cell contacts. In a previous report we could show that cocultivated hOBs strongly increase the expression of genes involved in extracellular matrix (ECM) formation in HUVECs, suggesting that ECM may be involved in the intercellular communication between hOBs and HUVECs. The present study aimed at investigating whether comparable changes occur in hOBs. We therefore performed a microarray analysis of hOBs cultivated in direct contact with HUVECs, revealing 1121 differentially expressed genes. The differentially expressed genes could be assigned to the functional clusters ECM, proliferation, apoptosis and osteogenic differentiation. In summary, our data demonstrate that HUVECs provoke complex changes in gene expression patterns in cocultivated hOBs and that ECM plays and important role in this interaction.

ORGANISM(S): Homo sapiens

SUBMITTER: Dietmar Pfeifer

PROVIDER: E-MTAB-4152 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:Apoptosis plays a pivotal role in embryogenesis and postnatal cell homeostasis, involving DNA or subcellular fragmentation, and shedding of small membranous microvesicles termed apoptotic bodies (AB). Following DNA damage, hypoxia, or vascular injury, the chemokine CXCL12 has been implicated in the recruitment of progenitor cells for tissue regeneration through its receptor CXCR4 and in mechanisms counteracting apoptosis. Whether AB deliver alarm signals for regenerative responses to neighbouring cells beyond recruitment or eat-me signals for phagocytes and relevance to diseases with abundant apoptosis, eg atherosclerosis, remains unknown. Here we show that endothelial cell-derived AB are generated during diet-induced atherosclerosis and can be transferred to recipient endothelial or smooth muscle cells to induce functional expression of CXCL12. This is mediated through miRNA-126 enriched in AB, which acts by silencing RGS16 translation and unlocking CXCR4 to unleash an auto-regulatory feedback loop inducing CXCL12. Injection of AB promoted mobilization and incorporation of progenitor cells, reducing diet-induced atherosclerosis in apolipoprotein E-deficient mice, and local transfer of microRNA-126 inhibited collar-induced arterial plaque formation. This was associated with increased smooth muscle content but decreased macrophage and apoptotic cell content, all features of plaque stability. Our data identify a new mechanism, by which AB confer microRNA-126 as a paracrine alarm messenger to enhance CXCR4 signals and CXCL12 expression, thereby limiting or repairing vascular damage. This adds to the important functions of microRNAs in health and disease and may extend to progenitor cell recruitment during other forms of tissue repair or homeostasis. AB were isolated from supernatants of apoptotic, serum-starved human umbilical vein endothelial cells (HUVECs) by sequential centrifugation steps. Total RNA was isolated from AB or HUVECs and microRNA was purified using the mirVanaTM miRNA Isolation Kit (Ambion). microRNA obtained from 10 µg of total RNA was labeled using the mirVanaTM miRNA Labeling Kit (Ambion) and fluorescent Cy3 (Molecular Probes), and hybridized to the Ambion mirVanaTM miRNA Bioarray (1566 v.1). Hybridized mirVana miRNA Bioarrays were scanned and quantified by using ImaGene 5.5.4 (Bio Discovery). Resulted signal intensities were background corrected and then normalized using variance stabilization normalization. (Huber, 2002).

Project description:Metastasizing tumor cells exit the vascular system through dynamic interactions with endothelial cells that line the internal surface of vessels. While extravasation is a key event within the metastatic cascade, the signals regulating tumor cell adhesion to the endothelium and their subsequent transendothelial migration are poorly understood. Here, we combined Stable Isotope Labeling by Amino acids in Cell culture (SILAC) and phosphoproteomic analysis to identify cell-specific signaling pathways regulated between interacting breast cancer cells and endothelial cells (see PRIDE repository PXD001558). Further co-culture experiments were performed alongside the phosphoproteomic analysis in order to control for the protein quantity. These are presented here. Using SILAC, cell-specific labels were introduced into MDA-MB-231-LM2 cells (Human Breast cancer) and HUVECs (Human endothelial cells) to ensure each cell type had a distinct and traceable phosphoproteome when tumor and endothelial cells were co-cultured. To probe regulatory signaling events triggered in cancer cells following contact with endothelial cells, we labeled LM2 cells with medium or heavy isotopomers of arginine and lysine (Arg+6 Da, Lys+4 Da and Arg+10 Da, Lys+8 Da respectively). Heavy-labeled LM2 cells were collected by enzyme-free cell dissociation buffer, thereby preserving membrane proteins and adhesion receptors, and seeded onto a monolayer of light-labeled (Arg+0 Da, Lys+0 Da) HUVECs. Following 15 min of co-culture, non-adherent LM2 cells were gently removed and cancer cells that had attached to the endothelial layer were lysed together with the HUVECs. In parallel, medium-labeled LM2 cells were collected under the same conditions and maintained as suspension cells in monoculture to represent circulating tumor cells prior to any contact with the endothelium. These were then added to the harvested LM2-HUVEC co-culture in a 1:1 ratio of heavy:medium-labeled cells to provide a point of reference. Based on the SILAC labeling of the different cell populations, light-labeled peptides were assigned to HUVECs, medium-labeled peptides to monocultured LM2 cells in suspension, and heavy-labeled peptides to LM2 cells that had made contact with HUVECs. As such, the heavy/medium ratio for each peptide was used to quantify phosphorylation-dependent signaling changes occurring specifically in the LM2 cells upon contact with HUVECs. Conversely, to elucidate signaling events in HUVECs that were initiated by contacting cancer cells, light-labeled LM2 cells were seeded on top of a confluent monolayer of heavy-labeled HUVECs, while medium-labeled HUVECs were maintained in monoculture. Following 15 min of co-culture, the unattached LM2 cells were removed. Cells were lysed, mixed in a 1:1 ratio of heavy:medium HUVECs, followed by membrane fractionation and phosphoproteomic analysis as described above. A variation in phospho-peptide quantity could be due to the experimental difficulties in mixing heavy and medium labels in a 1:1 ratio or a quick regulation of the protein quantity through modification of its expression/degradation balance. Thus, we performed relative quantification of non-phosphorylated peptides in parallel with the phosphoproteomic analysis to account for changes in total protein abundance (data presented here) or correct for experimental bias. Cytoplasmic fractions were analyzed by LC-MS/MS before TiO2 enrichment and their median log2(H/M) were used for normalization of the phosphoproteomic dataset. In order to increase the number of proteins quantified in the LM2 cells, we performed a supplementary co-culture experiment and fractionated the peptides by SDS-PAGE. In order to get a confident relative quantification of Ephrin type-A receptor 2 (EPHA2), we performed 2 independent experiments followed by EPHA2 IP and LC-MSMS.

Dataset Information

HOB Transcriptome after HUVEC-Cocultivation

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets