gene expression database and algorithm to define cell expression modules
Identifying gene expression modules that define human cell fates.
Specimen part
View SamplesThe classical concept of bone marrow-derived mesenchymal stem cells (BM-MSC), intended as a uniform, broad potent population, is progressively being substituted by the idea that the bone marrow harbors heterogeneous populations of non-hematopoietic stem cells. This in vivo heterogeneity is also amplified by the different experimental strategies used to isolate/culture them. Among the exogenous factors described to affect MSC in vitro growth, basic-fibroblast growth factor (bFGF) is one of the most common growth factors used to expand stem cells. Moreover, it has been reported that its signaling is associated with the mainteinance of stemness of a variety of stem cells, included MSC. Using an ectopic model of bone regeneration, we have previously described that the implantation of cells with different commitment levels, differentially influences the capacity to recruit host cells, activating endogenous regenerative mechanisms. Due to its properties, we here demonstrate that the addition of bFGF to primary BM cultures, leads to the selection of specific subpopulations able to induce a different host regenerative response, when in vivo implanted in association with suitable ceramic scaffolds. Moreover, taking advantage of a multiparametric and comparative genomic and proteomic approach, it has been evaluated how different culture conditions combine to bring about appreciable changes in the secretome of the cells, that consequently influence their in vivo regenerative behaviour. The full comprehension of the regulatory mechanisms that rule the host response depending on the type and differentiative stage of the transplanted cells could help us to develop novel clinical strategies where host cells could directly contribute to regenerate the appropriate tissue.
The role of bFGF on the ability of MSC to activate endogenous regenerative mechanisms in an ectopic bone formation model.
Specimen part, Disease
View SamplesThe balance between glycolytic and oxidative metabolism shifts during differentiation of human embryonic stem cells (hESCs) and during reprogramming of somatic cells into pluripotent stem cells. However the contribution of glycolytic metabolism to various stages of pluripotency is not well understood. Additionally, few tools have been developed that modulate pluripotent stem cell glycolytic metabolism to influence self-renewal or differentiation. Here we show that the degree of human pluripotency is associated with glycolytic rate, whereby naive hESCs exhibit higher glycolytic flux, increased MYC transcriptional activity, and elevated nuclear N-MYC levels relative to primed hESCs. Consistently, the inner cell mass of human blastocysts also exhibits increased MYC transcriptional activity relative to primed hESCs and elevated nuclear N-MYC levels. Expression of the lactate transporter, monocarboxylate transporter 1 (MCT1), is strongly associated with the pluripotent state, and reduction of glycolysis using a small molecule inhibitor towards MCT1 decreases self-renewal of nave hESCs and feeder-free cultured primed hESCs, but not that of primed hESCs grown in feeder-supported conditions. Lastly, reduction of glycolytic metabolism via MCT1 inhibition in feeder-free primed hESCs enhances neural lineage specification. These findings validate the association between glycolytic metabolism and pluripotency, reveal differences in the glucose metabolism of feeder- versus feeder-free cultured hESCs, and show that pharmacologic regulation of glycolysis can influence self-renewal and initial cell fate specification of human pluripotent stem cells.
Glycolytic Metabolism Plays a Functional Role in Regulating Human Pluripotent Stem Cell State.
Cell line, Treatment
View SamplesSeveral studies have described a crosstalk between the tumour cells of cHL, the Hodgkin- and Reed-Sternberg (HRS) cells, and cancer-associated fibroblasts (CAF). However, to date a deep molecular characterization of these fibroblasts is lacking. Aim of the present study therefore was a comprehensive characterization of these fibroblasts.
Fibroblasts in Nodular Sclerosing Classical Hodgkin Lymphoma Are Defined by a Specific Phenotype and Protect Tumor Cells from Brentuximab-Vedotin Induced Injury.
Disease
View SamplesIn order to understand the consequences of miR-210 blocking on the ischemia response, the transcriptomic changes were investigated by microarray technology in gastrocnemius muscles of ANTI-210 and SCR treated mice, 7 days after ischemia.
Hypoxia-Induced miR-210 Is Necessary for Vascular Regeneration upon Acute Limb Ischemia.
No sample metadata fields
View SamplesHypoxia augments human embryonic stem cell self-renewal via hypoxia-inducible factor 2 (HIF2) activated OCT4 (POU5F1) transcription. Hypoxia also increases the efficiency of reprogramming differentiated cells to a pluripotent-like state. Combined, these findings suggest that low oxygen (O2) tension would impair the purposeful differentiation of pluripotent stem cells. Here, we show that low O2 tension and HIF activity instead promotes appropriate hESC differentiation. Through gain and loss of function studies, we implicate O2 tension as a modifier of a key cell fate decision, namely whether neural progenitors differentiate towards neurons or glia. Furthermore, our data show that even transient changes in O2 concentration can affect cell fate through HIF by regulating the activity of MYC, a regulator of LIN28/let-7 that is critical for fate decisions in the neural lineage. We also identify key small molecules that can take advantage of this pathway to quickly and efficiently promote the development of mature cell types.
Defining the role of oxygen tension in human neural progenitor fate.
Specimen part
View SamplesThe aim of the project was to characterize the transcriptional landscape of human HUVEC cells exposed to oxidative stress (oxstress). In order to do so cell cultures have been exposed to 200uM H2O2 for either 16 hours or 36 hours to induce oxstress. Total ribodepleted RNA obtained from both time points have been sequenced and small RNA for the 16 hours time point have been sequenced as well. Datasets have been characterized and overlapped. This entry contains the dataset of small RNA. Overall design: Two conditions are available: control untreated HUVEC cells and HUVEC cells exposed to 200uM H2O2 for 16 hours. Each condition is available in triplicate. All samples underwent two unpooled rounds of sequencing, for a total of 24 samples.
Central role of the p53 pathway in the noncoding-RNA response to oxidative stress.
Cell line, Treatment, Subject
View SamplesThe short-lived turquoise killifish Nothobranchius furzeri (Nfu) is a valid model for aging studies. Here, we investigated its age-associated cardiac function. We observed oxidative stress accumulation and an engagement of microRNAs (miRNAs) in the aging heart. MiRNA-sequencing of 5 week (young), 12-21 week (adult) and 28-40 week (old) Nfu hearts revealed 23 up-regulated and 18 down-regulated miRNAs with age. MiR-29 family turned out as one of the most up-regulated miRNAs during aging. MiR-29 family increase induces a decrease of known targets like collagens and DNA methyl transferases (DNMTs) paralleled by 5´methyl-cytosine (5mC) level decrease. To further investigate miR-29 family role in the fish heart we generated a transgenic zebrafish model where miR-29 was knocked-down. In this model we found significant morphological and functional cardiac alterations and an impairment of oxygen dependent pathways by transcriptome analysis leading to hypoxic marker up-regulation. To get insights the possible hypoxic regulation of miR-29 family, we exposed human cardiac fibroblasts to 1% O2 levels. In hypoxic condition we found miR-29 down-modulation responsible for the accumulation of collagens and 5mC. Overall, our data suggest that miR-29 family up-regulation might represent an endogenous mechanism aimed at ameliorating the age-dependent cardiac damage leading to hypertrophy and fibrosis. Overall design: RNA was isolated from zebrafish heart samples (3 wt and 3 miR-29-sponge) and sequenced.
Age-dependent increase of oxidative stress regulates microRNA-29 family preserving cardiac health.
Specimen part, Subject
View SamplesRNA-binding proteins (RBPs) facilitate post-transcriptional control of eukaryotic gene expression at multiple levels. The RBP tristetraprolin (TTP/Zfp36) is a signal-induced phosphorylated anti-inflammatory protein guiding unstable mRNAs of pro-inflammatory proteins for degradation and preventing translation. Using iCLIP, we have identified numerous mRNA targets bound by wild-type TTP and by a non-MK2-phosphorylatable TTP mutant (TTP-AA) in 1h LPS-stimulated macrophages and correlated their interaction with TTP to changes at the level of mRNA abundance and translation in a transcriptome-wide manner. The close similarity of the transcriptome of TTP-deficient and TTP-expressing macrophages upon short LPS stimulation suggested an effective inactivation of TTP by MK2 under these conditions whereas retained RNA-binding capacity of TTP-AA to 3’UTRs caused profound changes in the transcriptome and translatome, altered NF-?B-activation and induced cell death. Increased TTP binding to the 3''UTR of feedback inhibitor mRNAs, such as Ier3, Dusp1 or Tnfaip3, in the absence of MK2-dependent TTP neutralization resulted in a strong reduction of their protein synthesis contributing to the deregulation of the NF-?B-signaling pathway. Taken together, our study uncovers a role for TTP in NF-?B-signaling and highlights the importance of fine-tuned TTP activity-regulation by MK2 in order to control feedback signaling during the inflammatory response. Overall design: Comparison of the transcriptomes of TTP knockout macrophages inducibly expressing GFP, GFP-TTP or GFP-TTP-AA (S52A, S178A) phosphorylation mutant during 1h LPS stimulation. 3 biological replicates per genotype and condition.
The RNA-binding protein TTP is a global post-transcriptional regulator of feedback control in inflammation.
Specimen part, Subject
View SamplesCurrent prognostic gene expression profiles for breast cancer mainly reflect proliferation status and are most useful in ER-positive cancers. Triple-negative breast cancers (TNBCs) are clinically heterogeneous, and prognostic markers and biology-based therapies are needed to better treat this disease.
A clinically relevant gene signature in triple negative and basal-like breast cancer.
Specimen part
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