In order to gain insight into the molecular pathogenesis of the myelodysplastic syndromes (MDS), we performed global gene expression profiling and pathway analysis on the hematopoietic stem cells (HSC) of 183 MDS patients as compared with the HSC of 17 healthy controls. The most significantly deregulated pathways in MDS include interferon signaling, thrombopoietin signaling and the Wnt pathway. Among the most significantly deregulated gene pathways in early MDS are immunodeficiency, apoptosis and chemokine signaling, whereas advanced MDS is characterized by deregulation of DNA damage response and checkpoint pathways. We have identified distinct gene expression profiles and deregulated gene pathways in patients with del(5q), trisomy 8 or 7/del(7q). Patients with trisomy 8 are characterized by deregulation of pathways involved in the immune response, patients with 7/del(7q) by pathways involved in cell survival, whilst patients with del(5q) show deregulation of integrin signaling and cell cycle regulation pathways. This is the first study to determine deregulated gene pathways and ontology groups in the HSC of a large group of MDS patients. The deregulated pathways identified are likely to be critical to the MDS HSC phenotype and give new insights into the molecular pathogenesis of this disorder thereby providing new targets for therapeutic intervention.
Deregulated gene expression pathways in myelodysplastic syndrome hematopoietic stem cells.
Specimen part, Disease
View SamplesLong noncoding RNAs (lncRNAs) are emerging as powerful regulators of adipocyte differentiation and gene expression. However, their physiological role in adipose tissue biology and systemic energy metabolism has not been established. Here we show that adipose tissue expression of Blnc1, a conserved lncRNA regulator of thermogenic genes, is highly induced in obese mice. Fat-specific inactivation of Blnc1 impairs cold-induced thermogenesis and browning, exacerbates obesity-associated brown fat whitening, and worsens adipose tissue inflammation and fibrosis, leading to more severe insulin resistance and hepatic steatosis. On the contrary, transgenic expression of Blnc1 in adipose tissue elicits the opposite and beneficial metabolic effects, supporting a critical role of Blnc1 in driving adipose adaptation during obesity. Mechanistically, Blnc1 cell-autonomously attenuates proinflammatory cytokine signaling and promotes fuel storage in adipocytes through its protein partner Zbtb7b. This study illustrates a surprisingly pleiotropic and dominant role of lncRNA in driving adaptive adipose tissue remodeling and preserving metabolic health.
The long noncoding RNA Blnc1 orchestrates homeostatic adipose tissue remodeling to preserve metabolic health.
Sex, Age, Specimen part, Treatment
View SamplesIn the present study, we investigated the consequences of n-3 polyunsaturated fatty acids (PUFA) depletion on hepatic lipid metabolism in mice fed during three months with a diet presenting a high n-6/n-3 PUFA ratio to induce n-3 PUFA depletion. Microarray analyses were performed to identify the molecular targets involved in the development of hepatic steatosis associated with n-3 PUFA depletion.
Hepatic n-3 polyunsaturated fatty acid depletion promotes steatosis and insulin resistance in mice: genomic analysis of cellular targets.
Sex, Specimen part, Treatment
View SamplesAdipose tissue stromal cells contribute to the regulation of adipose tissue in lean and obese states. Myeloid cells such as adipose tissue macrophages (ATMs) and dendritic cells (ATDCs) undergo both quantitative and qualitative changes with obesity. Due to similarity in markers the identify of adipose tissue dendritic cells and macrophages has been elusive. We have refined prior protocols to unambiguously discern ATM and ATDC in mice. We used microarrays to compare the profiles of ATMs and ATDC from gonadal adipose tissue from lean, obese, and formerly obese mice. We also isolated preadipocytes (PA) from lean and obese mice for comparison.
Adipose Tissue Dendritic Cells Are Independent Contributors to Obesity-Induced Inflammation and Insulin Resistance.
Sex, Specimen part
View SamplesHIF-1 plays a crucial role in sustaining glioblastoma (GBM) cell growth and the maintenance of their undifferentiated phenotype. However, HIF-1 has been suggested to interplay with Wnt signaling components, thus activating a neuronal differentiation process in both GBM and normal brain. Here, we show that a -catenin/TCF1/HIF-1 complex directly controls the transcription of neuronal differentiation genes in hypoxia. Conversely, at higher oxygen levels, the increased expression of TCF4 exerts a transcriptional inhibitory function on the same genomic regions, thus counteracting differentiation. Moreover, we demonstrate the existence of a positive correlation between HIF-1, TCF1 and neuronal phenotype in GBM tumors, accompanied by the over-expression of several Wnt signaling components, finally impacting on patient prognosis. In conclusion, we unveil a mechanism by which TCF1 and HIF-1 induce a reminiscent neuronal differentiation of hypoxic GBM cells, which is hampered, in normoxia, by high levels of TCF4, thus de facto sustaining cell aggressiveness.
HIF-1α/Wnt signaling-dependent control of gene transcription regulates neuronal differentiation of glioblastoma stem cells.
Specimen part
View SamplesGlioblastoma (GBM) is the most devastating tumour of the brain, endowed with a fatal prognosis. Indeed, the complete eradication of cancer cell disseminated outside the GBM mass still remains a crucial issue. Given the reported strong association existing between Annexin 2A (ANXA2) expression and cell dissemination in many cancers, we evaluated the effects exerted by the modulation of ANXA2 levels in GBM cells and assessed its potential in predicting patient outcome. Here, we show that expression of ANXA2 positively correlates with metastatic gene signatures and demonstrates to be prognostic by itself. Indeed, we prove that ANXA2 is involved in cell migration, invasion, cytoskeletal remodeling and proliferation in GBM cells. Moreover, we were able to construct a gene signature representative of ANXA2 inhibition, which showed a significant prognostic potential in different GBM patient cohorts.
Annexin 2A sustains glioblastoma cell dissemination and proliferation.
Specimen part
View Samplesphenotypic reprogramming ability of teh zebtafish brain microenviroment on GBM derived cells controlled by the activation of endogenous Wnt pathway
Wnt activation promotes neuronal differentiation of glioblastoma.
Specimen part, Time
View Samplesin the present study, we evaluated whether microbiota modulation is able to restore hepatic steatosis induced by n-3 PUFA depletion in mice. For this purpose, mice were fed during three months with a n-3 PUFA-depleted diet (presenting a high n-6/n-3 PUFA ratio), and then supplemented with fructooligosaccharides (FOS, 0.25g/day/mice), a prebiotic, during the last ten days of the experiment (DEF/FOS). In the same time, some n-3 PUFA-depleted mice were returned on a control diet during the last 10 days of treatment (DEF/CT) to compare the effect of FOS supplementation to a restored intake in n-3 PUFA. Microarray analyses were performed to identify the molecular targets modified by FOS supplementation in the liver of n-3 PUFA depleted mice. These mice were compared to control mice (fed a control diet during the 112 days of experiment) and to n-3 PUFA-depleted mice (fed a n-3 PUFA-depleted diet during the 112 days of experiment) for which the results have been previously published (Pachikian B.D. et al. PLoS One. 2011;6(8):e23365, accession number GSE26986)
Prebiotic approach alleviates hepatic steatosis: implication of fatty acid oxidative and cholesterol synthesis pathways.
Sex, Specimen part, Treatment
View SamplesThis is a transcriptomics analysis contributing to a bigger project that tries to shed light on the role of type 2 diabetes mellitus (T2DM) as a risk factor for colon cancer (CC). Here we present a gene expression screening of paired tumor and normal colon mucosa samples in a cohort of 42 CC patients, 23 of them with T2DM. Using gene set enrichment, we identified an unexpected overlap of pathways over-represented in diabetics compared to non-diabetics, both in tumor and normal mucosa, including diabetes-related metabolic and signaling processes. An integration with other -omic studies suggests that in diabetics, the local micro-environment in normal colon mucosa may be a factor driving field cancerization which may promote carcinogenesis. Several of these pathways converged on the tumor initiation axis TEAD/YAP-TAZ. Cell culture studies confirmed that high glucose concentrations upregulate this pathway in non-tumor colon cells. In conclusion, diabetes is associated to deregulation of cancer-related processes in normal colon mucosa adjacent to tissue which has undergone a malignant transformation. These data support the existence of the field of cancerization paradigm in diabetes and set a new framework to study link between diabetes and cancer.
Molecular evidence of field cancerization initiated by diabetes in colon cancer patients.
Specimen part
View SamplesThis is a transcriptomics analysis contributing to a bigger project that tries to shed light on the role of type 2 diabetes mellitus (T2DM) as a risk factor for colon cancer (CC). Here we present a gene expression screening of 7 colon tumor xenograft samples, 2 with diabetic mice and 5 with normal blood glucose levels. For xenograft model details see: Prieto I, et al. (2017) Colon cancer modulation by a diabetic environment: A single institutional experience. PLoS One 12(3):e0172300
Molecular evidence of field cancerization initiated by diabetes in colon cancer patients.
Specimen part
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