Several reports indicate that mesalazine (5-aminosalicylic acid or 5-ASA) is a promising candidate for the chemoprevention of Colo-Rectal Cancer (CRC) due to its ability to reach the purpose, yet avoiding at the same time the side effects that are usually determined by prolonged administrations of Non Steroidal Anti-Inflammatory Drugs. This activity of 5-ASA is probably the consequence of a number of effects determined on colon cancer cells and consisting of reduced proliferation, increased apoptosis and activation of cell cycle checkpoints. A recent observation has suggested that these effects could be mediated by the capacity of 5-ASA to interfere with the nuclear translocation of beta-catenin, in turn responsible for the inhibition of its transcription activity. The aim of our study was to better characterize the molecular mechanism by which 5-ASA inhibits the beta-catenin signaling pathway. To address this issue we assessed, by means of the Affymetrix microarray methodology, the transcriptome changes determined on Caco2 cells by a 96 h treatment with 20 mM mesalazine.
Mesalazine inhibits the beta-catenin signalling pathway acting through the upregulation of mu-protocadherin gene in colo-rectal cancer cells.
No sample metadata fields
View SamplesHuman myelopoiesis is an exciting biological model for cellular differentiation since it represents a plastic process where pluripotent stem cells gradually limit their differentiation potential, generating different precursor cells which finally evolve into distinct terminally differentiated cells. This study aimed at investigating the genomic expression during myeloid differentiation through a computational approach that integrates gene expression profiles with functional information and genome organization. The genomic distribution of myelopoiesis genes was investigated integrating transcriptional and functional characteristics of genes. The analysis of genomic expression during human myelopoiesis using an integrative computational approach allowed discovering important relationships between genomic position, biological function and expression patterns and highlighting chromatin domains, including genes with coordinated expression and lineage-specific functions.
Motif discovery in promoters of genes co-localized and co-expressed during myeloid cells differentiation.
No sample metadata fields
View SamplesHuman myelopoiesis is an exciting biological model for cellular differentiation since it represents a plastic process where pluripotent stem cells gradually limit their differentiation potential, generating different precursor cells which finally evolve into distinct terminally differentiated cells. This study aimed at investigating the genomic expression during myeloid differentiation through a computational approach that integrates gene expression profiles with functional information and genome organization. The genomic distribution of myelopoiesis genes was investigated integrating transcriptional and functional characteristics of genes. The analysis of genomic expression during human myelopoiesis using an integrative computational approach allowed discovering important relationships between genomic position, biological function and expression patterns and highlighting chromatin domains, including genes with coordinated expression and lineage-specific functions.
Motif discovery in promoters of genes co-localized and co-expressed during myeloid cells differentiation.
No sample metadata fields
View SamplesAlthough a considerable number of reports indicate an involvement of the Hox-A10 gene in the molecular control of hematopoiesis, the conclusions of such studies are quite controversial since they support, in some cases, a role in the stimulation of stem cell self-renewal and myeloid progenitor expansion while, in others, implicate this transcription factor in the induction of monocyte - macrophage differentiation. To clarify this issue we analyzed the biological effects and the transcriptome changes determined in human primary CD34+ hematopoietic progenitors by retroviral transduction of a full length Hox-A10 cDNA. The results obtained clearly indicated that this homeogene is an inducer of monocyte differentiation, at least partly acting through the up-regulation of MafB gene, recently identified as master regulator of such maturation pathway. By using a combined approach based on computational analysis, EMSA experiments and luciferase assays, we were able to demonstrate the presence of a Hox-A10 binding site in the promoter region of the MafB gene, which suggested the likely molecular mechanism underlying the observed effect. Interestingly, stimulation of the same cells with the Vitamin D3 monocyte differentiation inducer resulted in a clear increase of Hox-A10 and MafB transcripts, indicating the existence of a precise transactivation cascade involving VDR, Hox-A10 and MafB transcription factors. Altogether these data allow to conclude that the Vitamin D3 / Hox-A10 pathway supports MafB function during the induction of monocyte differentiation.
The vitamin D3/Hox-A10 pathway supports MafB function during the monocyte differentiation of human CD34+ hemopoietic progenitors.
No sample metadata fields
View SamplesB-cell chronic lymphocytic leukemia (B-CLL) is characterized by a highly variable clinical course that reflects its heterogeneous genomic pattern. To better define molecular subtypes of the disease, we performed SNP and gene expression profiling microarray analyses in a panel of early stage (Binet A) patients. A clustering analysis of genomic profiles identified four significant groups mainly driven by del(13)(q14) and trisomy 12. Notably, patients with del(13)(q14) were grouped in two separate clusters based on the presence of a biallelic loss and the extension of the deletion. The shorter monoallelic deleted 13q14 region was found to be 635 kb in length, not encompassing the mir-15a/16-1 locus. Interestingly, the mir-15a and mir-16 expression was found to be significantly down-regulated only in patients with biallelic loss. Furthermore, a multiclass supervised analysis identified a different transcriptional signatures in the two genomic subgroups with del(13)(q14). Finally, an integrative approach identified 93 transcripts, mainly mapped to chromosome 12 and 13q12-q14.3, whose expression was significantly correlated with the DNA copy number. Overall, our data further support the notion that transcription deregulation in B-CLL could be mostly due to a gene dosage effect and underscore the presence of two distinct molecular types of 13q14 deleted patients with potential clinical relevance.
Integrative genomics analyses reveal molecularly distinct subgroups of B-cell chronic lymphocytic leukemia patients with 13q14 deletion.
Sex, Specimen part, Disease
View SamplesNucleotides triphosphates are extracellular messengers binding to specific plasma membrane receptors (P2Rs) that modulate responses as different as proliferation, differentiation, migration or cell death on several cell types including hematopoietic stem cells. Little and controversial information is available on the role of extracellular nucleotides in human mesenchimal stem cells (hMSCs). In this study, we assessed whether P2Rs are expressed and functional in bone marrow-derived hMSCs. Our results demonstrated, at the mRNA and protein level, the expression of all P2X and P2Y receptor subtypes identified so far. P2R activation by their natural ligands adenosine triphosphate (ATP) and uridine triphosphate (UTP) induced in hMSCs, intracellular Ca2+ concentration changes, plasma membrane depolarization and permeabilization. hMSCs were resistant to the cytotoxic effects of high dose ATP despite the expression of permeabilizing P2Rs as demonstrated by the lack of morphological changes, significant release of intracellular markers of cell death or modification of the mitochondrial network. Gene expression profiling revealed the down-regulation of cell proliferation genes whereas genes involved in cell migration and cytokine production were strongly up-regulated by ATP. Functional studies confirmed the inhibitory activity of ATP on proliferation of hMSCs and clonogenic progenitors. Moreover, ATP exerted a chemotactic effect on hMSCs and increased their migration in response to the chemokine CXCL12. Finally, whereas ATP did not affect T-cell inhibitory activity of hMSCs, the nucleotide increased the production of pro-inflammatory cytokines by hMSCs. Thus, our data show that purinergic signaling modulates hMSC functions and point to a role for extracellular nucleotides on hMSCs biology.
Purinergic stimulation of human mesenchymal stem cells potentiates their chemotactic response to CXCL12 and increases the homing capacity and production of proinflammatory cytokines.
No sample metadata fields
View SamplesHistone deacetylase (HDAC) inhibitors are widely utilized in hematopoietic malignance therapy; nevertheless, little is currently known concerning their effects on normal myelopoiesis. In order to investigate a putative interference of HDAC inhibitors in myeloid commitment of hematopoietic stem/progenitor cells (HSPCs) we treated CD34+ cells with valproic acid (VPA). Moreover, we investigate changes in gene expression induced by VPA treatment on HSPCs, by means of microarray analysis in VPA treated and untreated (CTR) CD34+ cells.
Valproic acid triggers erythro/megakaryocyte lineage decision through induction of GFI1B and MLLT3 expression.
Specimen part, Treatment
View SamplesIn the present study, we investigated whether, and to what extent, P2Rs and their ligands are involved in the regulation of AML cells. Our findings show that AML blasts express several receptors belonging to the P2X and P2Y family. Although different samples respond differently to ATP and UTP stimulation (reflecting the variability intrinsic to the group of acute myeloid leukemias), all the tested samples appear to be responsive to purinergic signalling, as demonstrated by intracellular calcium mobilization.
Purinergic signaling inhibits human acute myeloblastic leukemia cell proliferation, migration, and engraftment in immunodeficient mice.
Specimen part
View SamplesRole of beta-arrestin2 in response to intermittent or continuous parathyroid hormone (PTH) treatment.
Beta-arrestin2 regulates parathyroid hormone effects on a p38 MAPK and NFkappaB gene expression network in osteoblasts.
None
Sex, Age, Specimen part, Disease, Compound
View SamplesThis experiment was carried out in the context of a study aimed to identify the function of the transcription facotrs HIF-1a in the pathogenesis of chronic lymphocytic leukemia (CLL).
HIF-1α regulates the interaction of chronic lymphocytic leukemia cells with the tumor microenvironment.
Sex, Cell line
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