Project description:Myelodysplastic syndromes (MDS) present a wide range of hematopoietic stem cell disorders with a tendency to evolve into acute leukemia. Long noncoding RNAs (lncRNAs) play multiple roles in hematopoiesis, contributing to the pathogenesis of hematologic malignancies and representing a new class of biomarkers and therapeutic targets. We aimed to characterize lncRNAs deregulated in MDS that may function in the disease pathogenesis and those that could serve as novel potential biomarkers of the disease. We performed a microarray expression profiling of lncRNAs and protein-coding genes (PCGs) in CD34+ bone marrow cells of MDS patients. Expression profiles were generated to analyze lncRNA expression with relation to different aspects of the disease (i.e., diagnosis, disease subtypes, cytogenetic and mutational aberrations, and risk of progression).
Project description:In this study, we assessed the effects of lysyl oxidase (LOX/LOXL) inhibition on the composition of extracellular matrix (ECM) produced by in vitro expanded bone marrow derived mesenchymal stromal cells (MSCs) of n=3 patients with myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN).
Project description:Control of oxidative stress in the bone marrow (BM) is key for maintaining the balance between self-renewal, proliferation, and differentiation of hematopoietic cells. Breakdown of this regulation can lead to diseases characterized by BM failure such as the myelodysplastic syndromes (MDS). To better understand the role of oxidative stress in MDS development, we compared protein carbonylation as an oxidative stress marker in BM of patients with MDS and control subjects, and also patients with MDS under treatment with the iron chelator deferasirox.
Project description:Myelodysplastic syndromes (MDS) are a group of clonal hematological disorders characterized by ineffective hematopoiesis with morphological evidence of marrow cell dysplasia resulting in peripheral blood cytopenia. Microarray technology has permitted a refined high-throughput mapping of the transcriptional activity in the human genome. Noncoding-RNAs (ncRNAs) transcribed from intronic regions of genes are involved in a number of processes related to post-transcriptional control of gene expression, and in the regulation of exon-skipping and intron retention. Characterization of ncRNAs in progenitor cells and stromal cells of MDS patients could be strategic for understanding gene expression regulation in this disease. In this study, gene expression profiles of CD34+ and stromal cells of MDS patients with refractory anemia with ringed sideroblasts (RARS) subgroup were compared those of healthy individuals, using 44k combined intron-exon oligoarrays, which included probes for protein-coding genes, for sense and antisense strands of totally intronic noncoding (TIN) and for partially intronic noncoding (PIN) RNAs. In CD34+ cells of MDS-RARS patients, 217 genes were significantly differentially expressed (q-value < 0.01) in comparison to healthy individuals, of which 68 (31%) were noncoding transcripts. In stromal cells of MDS-RARS, 13 genes were significantly differentially expressed (q-value < 0.05) in comparison to healthy individuals, of which 4 (30%) were noncoding transcripts. These results demonstrated, for the first time, in CD34+ cells and stromal cells the differential ncRNA expression profile between MDS-RARS and healthy individuals, suggesting that ncRNAs may play an important role during the development of myelodysplastic syndromes. Bone marrow (BM) CD34+ cell samples were collected from 4 healthy subjects and from 4 MDS patients. Stromal samples were collected from 4 healthy subjects and 3 MDS patients. All patients were diagnosed as RARS according to the French-American-British (FAB) classification and did not present chromosomal abnormalities; they received no growth factors or any further MDS treatment.
Project description:SF3B1 mutations, which occur in 20% of patients with myelodysplastic syndromes (MDS), are the hallmarks of a specific MDS subtype, MDS with ringed sideroblasts (MDS-RS), which is characterized by the accumulation of erythroid precursors in the bone marrow.
Project description:Transcriptome analysis of total RNA from bone marrow (BM) mononuclear cells of MDS patients and normal dornors Global gene expression and alternative splicing profiling among patients with myelodysplastic syndrome (MDS) compared with normal donors
Project description:Myelodysplastic syndromes (MDS) are a heterogeneous group of hematopoietic disorders characterized by ineffective blood cell production and a high risk of progression to acute myeloid leukemia (AML). CD34+ hematopoietic stem and progenitor cells (HSPCs) play a critical role in the pathophysiology of MDS, yet the proteomic changes underlying the disease remain poorly characterized. This project focuses on performing comprehensive quantitative proteomic profiling of CD34+ cells isolated from the bone marrow of MDS patients and healthy controls. By leveraging advanced mass spectrometry and quantitative proteomics techniques, we aim to identify unbiased differences in protein expression and pathways between diseased and healthy cells. These findings will contribute to a deeper understanding of the molecular mechanisms driving MDS and may reveal potential biomarkers or therapeutic targets.
Project description:Myelodysplastic syndromes (MDS) are myeloid hematopoietic stem cell tumors displaying complex pathogenesis with a high risk of transformation to acute myeloid leukemia (AML). The efficacy of current clinical drugs is limited. Thus, identifying high-efficiency drugs of MDS remain urgent. Celastrol, a natural small molecule compound derived from the traditional Chinese medicinal herb Tripterygium wilfordii, has shown powerful antitumor effects. However, the effects of celastrol on MDS are unknown. In this study, we found that celastrol significantly inhibited the viability of MDS cell lines and bone marrow mononuclear cells (BMMCs) from MDS patients, and induced apoptosis. Through transcriptome sequencing, we found that celastrol induced the pro-apoptotic ER stress response in MDS cell. Mechanistically, celastrol activated the pro-apoptotic ER-stress branch involving the pancreatic eIF2α kinase (PERK) pathway.
Project description:Myelodysplastic Syndromes (MDSs) are a heterogeneous family of clonal disorders of hematopoietic stem cells characterized by ineffective hematopoiesis and frequently leukemia progression. To exlore how MDS develop into leukemia, we performed the transcriptional profiling of lesional cells and normal lymphoid cells from the MDS patients. Bone marrow cells from the MDS patients were sorted into blastic, myeloid, erythroid and lymphoid fractions by flow cytometry and then were profiled transcriptionally by Human Human Genome U133 Plus 2.0 arrays. Differentially expressed genes between lesional cells and lymphoid cells were identified by SAM.
Project description:Genome-wide expression and methylation profiling identifies novel targets with aberrant hypermethylation and reduced expression in low-risk myelodysplastic syndromes (MDSs). Gene expression profiling signatures may be used to classify the subtypes of Myelodysplastic syndrome (MDS) patients. However, there are few reports on the global methylation status in MDS. The integration of genome-wide epigenetic regulatory marks with gene expression levels would provide additional information regarding the biological differences between MDS and healthy controls. Gene expression and methylation status were measured using high-density microarrays. A total of 552 differentially methylated CpG loci were identified as being present in low-risk MDS; hypermethylated genes were more frequent than hypomethylated genes. In addition, mRNA expression profiling identified 1005 genes that significantly differed between low-risk MDS and the control group. Integrative analysis of the epigenetic and expression profiles revealed that 66.7% of the hypermethylated genes were underexpressed in low-risk MDS cases. Gene network analysis revealed molecular mechanisms associated with the low-risk MDS group, including altered apoptosis pathways. The two key apoptotic genes BCL2 and ETS1 were identified as silenced genes. In addition, the immune response and micro RNA biogenesis were affected by the hypermethylation and underexpression of IL27RA and DICER1. Our integrative analysis revealed that aberrant epigenetic regulation is a hallmark of low-risk MDS patients and could have a central role in these diseases. Low-risk MDS patients and age-matched controls without haematological malignancies were included in the study. Mononuclear cells were isolated from bone marrow samples of low-risk MDS patients and controls by density gradient (Ficoll). A cohort of 18 patients with low-risk MDS and seven controls were included in a simultaneous integrative study of methylation and expression, while the whole series was used as a control group of expression data.