Identification of Prognostic Markers by Gene Expression Profiling In Myelodysplastic Syndrome Hematopoietic Stem Cells

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 298-298 ◽  
Author(s):  
Andrea Pellagatti ◽  
Mario Cazzola ◽  
Aristoteles Giagounidis ◽  
Janet Perry ◽  
Luca Malcovati ◽  
...  

Abstract Abstract 298 The myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematopoietic stem cell malignancies that are characterized by ineffective hematopoiesis resulting in peripheral cytopenias and a hypercellular bone marrow. Approximately 40% of patients with MDS will develop an acute myeloid leukemia. It is important to establish prognosis of MDS patients since the treatment options vary from supportive care to bone marrow transplantation. In order to determine the relationship of gene expression levels to prognosis and so identify new molecular markers, we have used gene expression profiling to study the transcriptome of the hematopoietic stem cells of 125 MDS patients with a minimum 12 month follow up. The CD34+ cells obtained from MDS patients and healthy individuals were analyzed using Affymetrix U133 Plus2.0 arrays. The patients were split randomly in a training set (n=84) and a test set (n=41). Supervised principal components analysis was used to identify genes correlated with survival. Using the 84 patients in the training set, the Cox scores were computed for each gene, and the principal components calculated on the genes with the highest Cox scores. The first of the principal components was then used to generate a regression model to predict the survival in the test set. Finally, for each probe set an importance score was calculated equal to its correlation with the supervised principal component predictor. This approach returned a list of 150 top ranked probe sets correlated with survival. Patients in the training set were split into tertiles based on the predictor (low, medium and high score) and patients in the test set were assigned to their predicted class, and Kaplan-Meier plots were generated for both training and test set. The differences in survival for both training and test set were statistically significant (Figure 1). Top ranked genes showing lower expression levels in patients with shorter survival include CDH1, LEF1 and AKAP12/Gravin. Top ranked genes showing higher expression levels in patients with shorter survival include IL23A, WT1 and PTHR2. Figure 2 shows survival of patients divided into tertiles of expression for the individual genes CDH1, LEF1 and WT1. It is probable that the genes identified in this study will become the first validated molecular markers for MDS prognosis. Multivariate analysis is currently being performed. Figure 1 Figure 1. Figure 2 Figure 2. Disclosure: No relevant conflicts of interest to declare.

2017 ◽  
Vol 60 (6) ◽  
pp. 326-334 ◽  
Author(s):  
Carla Martins Kaneto ◽  
Patrícia S. Pereira Lima ◽  
Karen Lima Prata ◽  
Jane Lima dos Santos ◽  
João Monteiro de Pina Neto ◽  
...  

BMC Genomics ◽  
2011 ◽  
Vol 12 (1) ◽  
pp. 461 ◽  
Author(s):  
Adriane Menssen ◽  
Thomas Häupl ◽  
Michael Sittinger ◽  
Bruno Delorme ◽  
Pierre Charbord ◽  
...  

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1762-1762
Author(s):  
Christopher Y. Park ◽  
Wendy W Pang ◽  
Peter L Greenberg ◽  
Irving L. Weissman

Abstract Abstract 1762 Poster Board I-788 The myelodysplastic syndromes (MDS) represent a heterogeneous group of disorders characterized by peripheral cytopenias due to impaired hematopoietic differentiation. To date, most data characterizing the immature hematopoietic compartment in MDS have relied on evaluation of CD34+ bone marrow cells, which are a heterogeneous population containing a predominance of oligo- and unilineage-potent progenitors and few hematopoietic stem cells (HSC). In this study we show that MDS are disorders of HSC, evidenced by the presence of recurrent cytogenetic alterations, including -5q, -7, and -20q, in highly purified HSC (Lin-CD34+CD38-CD90+CD45RA-) by FISH. Because MDS HSC harbor cytogenetic changes, we sought to better characterize the molecular basis of MDS HSC function by performing whole transcriptome analysis of highly purified HSC and committed myeloid progenitor populations from low-risk (n=8) and high-risk (n=2) MDS patients. When compared to control HSC from healthy patients (n=10), MDS HSC showed broad transcriptional changes. Using the significance analysis of microarrays (SAM) algorithm and Ingenuity Pathways Analysis software, we identified 3,258 differentially expressed genes (FDR < 0.1) with increased expression of genes positively associated with cell growth and proliferation (p < 0.001) and increased expression of inflammatory response genes (p < 0.015). Interestingly, while MDS common myeloid progenitors (CMP, Lin-CD34+CD38+CD123+CD45RA-) showed increased expression of cell death-related genes when compared to normal CMP (p < 0.001), neither MDS HSC nor multipotent progenitors (MPP, Lin-CD34+CD38-CD90-CD45RA-) showed significant differential expression of these genes when compared to their normal counterparts. To assess the cellular and developmental correlates of HSC/committed progenitor transcriptional changes, we evaluated by flow cytometry the frequency of HSC and committed myeloid progenitors in bone marrow aspirates from 35 low-risk MDS, 6 high-risk MDS and 32 healthy patient samples (range 4-84 yo). Low-risk MDS bone marrow samples showed significantly increased numbers of HSC compared to normal bone marrow samples (+3-fold change, p < 0.03). In addition, myeloid progenitor composition was frequently altered in low-risk MDS patients, with decreased percentages of granulocyte-macrophage progenitors (GMP, Lin-CD34+CD38+CD123+CD45RA+) when expressed as a percentage of total myeloid progenitors [including GMP, CMP and megakaryocyte-erythroid progenitors (MEP, Lin-CD34+CD38+CD123loCD45RA-)] (-2.3-fold change, p < 1e-6). This altered myeloid progenitor profile was highly specific to MDS, even when MDS patient samples were compared to a group of control bone marrow samples from non-MDS patients exhibiting at least one cytopenia (n=34, p < 1e-5), allowing for the distinction of MDS samples from non-MDS cytopenias with 0.89 sensitivity and 0.89 specificity. Together, these data indicate that MDS HSC exhibit significantly altered gene expression profiles and suggest that gene expression changes in MDS HSC induce the altered developmental fate decisions and transcriptional changes observed in MDS committed myeloid progenitors. These data also demonstrate that the changes in MDS myeloid progenitor composition may provide a novel, flow cytometric method for distinguishing MDS from other hematologic conditions that mimic MDS. Finally, these studies indicate that molecular characterization of MDS phenotypes may require evaluation of purified hematopoietic progenitors in order to account for the differential effect of MDS-associated changes on specific hematopoietic progenitor populations. Disclosures Weissman: Amgen: Equity Ownership; Cellerant Inc.: Founder; Stem Cells Inc.: Equity Ownership, Founder; U.S. Patent Application 11/528,890 entitled “Methods for Diagnosing and Evaluating Treatment of Blood Disorders.”: Patents & Royalties.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1505-1505
Author(s):  
Wendy W. Pang ◽  
Elizabeth A. Price ◽  
Irving L. Weissman ◽  
Stanley L. Schrier

Abstract Abstract 1505 Poster Board I-528 Aging of the human hematopoietic system is associated with an increase in the development of anemia, myeloid malignancies, and decreased adaptive immune function. While the hematopoietic stem cell (HSC) population in mouse has been shown to change both quantitatively as well as functionally with age, age-associated alterations in the human HSC and progenitor cell populations have not been characterized. In order to elucidate the properties of an aged human hematopoietic system that may predispose to age-associated hematopoietic dysfunction, we evaluated and compared HSC and other hematopoietic progenitor populations prospectively isolated via fluorescence activated cell sorting (FACS) from 10 healthy young (20-35 years of age) and 8 healthy elderly (65+ years of age) human bone marrow samples. Bone marrow was obtained from hematologically normal young and old volunteers, under a protocol approved by the Stanford Institutional Review Board. We determined by flow cytometry the distribution frequencies and cell cycle status of HSC and progenitor populations. We also analyzed the in vitro function and generated gene expression profiles of the sorted HSC and progenitor populations. We found that bone marrow samples obtained from normal elderly adults contain ∼2-3 times the frequency of immunophenotypic HSC (Lin-CD34+CD38-CD90+) compared to bone marrow obtained from normal young adults (p < 0.02). Furthermore, upon evaluation of cell cycle status using RNA (Pyronin-Y) and DNA (Hoechst 33342) dyes, we observed that a greater percentage of HSC from young bone marrow are in the quiescent G0- phase of the cell cycle compared to elderly HSC, of which there is a greater percentage in G1-, S-, G2-, or M-phases of the cell cycle (2.5-fold difference; p < 0.03). In contrast to the increase in HSC frequency, we did not detect any significant differences in the frequency of the earliest immunophenotypic common myeloid progenitors (CMP; Lin-CD34+CD38+CD123+CD45RA-), granulocyte-macrophage progenitors (GMP; Lin-CD34+CD38+CD123+CD45RA+), and megakaryocytic-erythroid progenitors (MEP; Lin-CD34+CD38+CD123-CD45RA-) from young and elderly bone marrow. We next analyzed the ability of young and elderly HSC to differentiate into myeloid and lymphoid lineages in vitro. We found that elderly HSC exhibit diminished capacity to differentiate into lymphoid B-lineage cells in the AC6.21 culture environment. We did not, however, observe significant differences in the ability of young and elderly HSC to form myeloid and erythroid colonies in methylcellulose culture, indicating that myelo-erythroid differentiation capacity is preserved in elderly HSC. Correspondingly, gene expression profiling of young and elderly human HSC indicate that elderly HSC have up-regulation of genes that specify myelo-erythroid fate and function and down-regulation of genes associated with lymphopoiesis. Additionally, elderly HSC exhibit increased levels of transcripts associated with transcription, active cell-cycle, cell growth and proliferation, and cell death. These data suggest that hematopoietic aging is associated with intrinsic changes in the gene expression of human HSC that reflect the quantitative and functional alterations of HSC seen in elderly bone marrow. In aged individuals, HSC are more numerous and, as a population, are more myeloid biased than young HSC, which are more balanced in lymphoid and myeloid potential. We are currently investigating the causes of and mechanisms behind these highly specific age-associated changes in human HSC. Disclosures: Weissman: Amgen: Equity Ownership; Cellerant Inc.: ; Stem Cells Inc.: ; U.S. Patent Application 11/528,890 entitled “Methods for Diagnosing and Evaluating Treatment of Blood Disorders.”: Patents & Royalties.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4822-4822
Author(s):  
Kavitha Siva ◽  
Pekka Jaako ◽  
Kenichi Miharada ◽  
Emma Rörby ◽  
Mats Ehinger ◽  
...  

Abstract Abstract 4822 Hematopoiesis is a complex process where a limited number of stem cells give rise to all mature blood cells. It involves interplay of several factors, many of which are yet to be identified. In a search for novel regulators of hematopoiesis, we chose to study SPARC (Secreted Protein Acidic and Rich in Cysteine, also known as Osteonection and BM40) because it is downregulated upon hematopoietic differentiation (Bruno et al., Mol Cell Biol, 2004) and might therefore play a role in the regulation of hematopoietic stem cells (HSC). SPARC is a matricellular protein that forms a major component of bone and is ubiquitously expressed in a variety of tissues. It is the founding member of a family of SPARC-like proteins. Several publications have indicated an important role for SPARC in hematopoiesis. In particular – knockdown of SPARC in zebrafish embryos resulted in an altered number of circulating blood cells, and a knockout mouse model showed thrombocytopenia and reduced erythroid colony formation. We carried out an in depth phenotypic and functional analysis of the hematopoietic system of SPARC knockout mice; using it as a model to gain insight into the role of SPARC in hematopoiesis. These mice are viable and fertile but show severe osteopenia and age-onset cataract at about six months of age. They also show an altered response to tumour growth and wound healing. We used mice (129SVJ background) (Gilmour et al. EMBO, 1998) that were less than six months old. These mice had normal peripheral blood counts and the bone marrow and spleen showed no alterations in morphology or cellularity. A detailed phenotypic analysis of precursors within the bone marrow showed no significant differences in myelo-erythroid precursors as compared to wild types (n=6). Though in vitro, the precursors showed lower ability to form BFU-E (n=5, p=0.048). In transplantations of lethally irradiated recipient mice, SPARC knockout cells gave rise to multi-lineage long-term reconstitution. Also, when competed with wild type cells, they provided reconstitution as well as their wild type counterparts. When SPARC knockout mice (n=8) were transplanted with wild type cells, there was normal reconstitution, indicating that a SPARC deficient niche can fully support normal hematopoiesis. We also tested if SPARC deficient mice respond differently to hematopoietic stress. We subjected mice (n=7) to sub lethal dose of irradiation and to experimentally induced anemia (n=7) and followed recovery by analyzing peripheral blood counts. In both SPARC knockouts and wild type mice, the blood counts recovered in a similar fashion. In conclusion, we find that SPARC is dispensable for murine hematopoiesis. It is possible that there are compensatory mechanisms involving other members of the SPARC family that ultimately lead to normal hematopoiesis in the murine model. In humans, SPARC maps to the deleted region in 5q MDS and has been reported to be 71 % down regulated in patient samples (Lehmann et al. Leukemia, 2007). It is the most prominent gene that is up regulated in response to lenalidomide, a drug that inhibits the malignant clone (Pellagatti et al. PNAS, 2007). SPARC is thus increasingly speculated to be involved in the pathophysiology of this hematopoetic disease. We analysed the expression levels of SPARC mRNA in the hematopoietic stem/progenitor cell compartment and found high expression levels in the CD34+ fraction of human cord blood cells. In contrast, there is very low level of SPARC expression in all compartments of murine HSCs. Therefore SPARC function may play a more important role in human hematopoiesis than in murine blood cell regulation. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5951-5951
Author(s):  
Liu-Jiang Song ◽  
Xin-Hua Zhang ◽  
Jun Zhu ◽  
Jue-Lian Wu ◽  
Xiao-Ling Yin ◽  
...  

Abstract Background: The most severe form of β-thalassemia, β°-thalassemia major, is characterized by the complete absence of normal β-globin chain, and is often lethal. Autologous transplantation of genetically-modified hematopoietic stem cells (HSCs) using lentiviral vectors have been used successfully to achieve clinical efficacy in one patient, although clonal expansion of a myeloid cell population also occurred in this patient which was associated with the activation of a cellular proto-oncogene, HMGA2. We reasoned that recombinant vectors based on a non-pathogenic human parvovirus, the adeno-associated virus (AAV), might offer a safer alternative. We have previously documented that although the conventional single-stranded (ss) AAV2 vectors mediated β-globin gene transfer and expression in primary human fetal liver cells and in human HSCs from patients with β-thalassemia patients in vitro, the level of transgene expression was sub-optimal. In the present study, we investigated whether double-stranded self-complementary (sc) AAV2 vectors could overcome this limitation. Methods: Human HSCs, obtained from a β-thalassemia homozygous patient, were mock-transduced or transduced with recombinant scAAV2-β-globin vectors at 5×104 vgs/cell, followed by i.v. injection into sub-lethally irradiated NOD/SCID mice (2.65 cGy total body irradiation), which were also pre-treated with 200 µg purified anti-IL2RB/CD122 monoclonal antibody. Recipient mice were sacrificed 12 weeks post-transplantation. Bone marrow cells from recipient mice were analyzed by BFU-E assays. Human β-globin gene expression in human erythroid progenitor cells from transplanted mice was evaluated by RT-PCR. Results: Pre-treatment of NOD/SCID mice with anti-CD122 antibody improves engraftment of human HSCs in bone marrow of receipt mice. Human β-actin (538-bp) and β-globin (272-bp) transcripts were detected by RT-PCR in bone marrow cells from all recipient mice, indicating that recombinant scAAV2-β-globin–transduced HSCs from a patient with β-thalassemia were successfully transduced and transplanted in these mice and that human β-globin gene was transcriptionally active 12 weeks post-transplantation. Conclusion: Our results indicate that human HSCs from β-thalassemia patients can be efficiently transduced by recombinant scAAV2-β-globin vectors followed by expression of normal human β-globin gene. These studies provide the proof-of-concept that scAAV2 vector-mediated gene transfer into human HSCs might be a potentially safer alternative approach for gene therapy of β-thalassemia. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Author(s):  
Chao Huang ◽  
Xiaojian Zhu ◽  
Jiefeng Zhao ◽  
Fanqin Bu ◽  
Jun Huang ◽  
...  

Abstract Background Gastric cancer (GC) is a malignant tumor with high mortality. MicroRNAs (miRNAs) participate in various biological processes and disease pathogenesis by targeting messenger RNA (mRNA). The purpose of this study was to identify potential prognostic molecular markers of GC and to characterize the molecular mechanisms of GC. Methods A gene expression profiling dataset (GSE54129) and miRNA expression profiling dataset (GSE113486) were downloaded from the Gene Expression Omnibus (GEO) database. A miRNA-mRNA interaction network was established. Functional and pathway enrichment analyses were performed for differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) using FunRich, the clusterProfiler package, and DIANA-mirPath. Survival analysis of key molecular markers was performed using the online tool Kaplan-Meier Plotter and the database OncomiR. Finally, experiments were carried out to verify the expression levels and biological functions of a key gene. Results A total of 390 DEMs and 341 DEGs were identified. Ultimately, 45 genes and 31 miRNAs were selected to establish a miRNA-mRNA regulatory network. Four hub genes (ZFPM2, FUT9, NEUROD1 and LIPH) and six miRNAs (hsa-let-7d-5p, hsa-miR-23b-3p, hsa-miR-23a-3p, hsa-miR-133b, hsa-miR-130a-3p and hsa-miR-124-3p) were identified in the network. DEGs and DEMs were associated with ECM-receptor interactions and metabolic pathways. Two genes (ZFPM2 and LIPH) and two miRNAs (hsa-miR-23a-3p and hsa-miR-130a-3p) were observed to be related to the prognosis of GC. ZFPM2 was highly expressed in GC tissues and various GC cell lines and could promote the proliferation, invasion and migration of GC cells. Conclusion The expression levels of ZFPM2, LIPH, hsa-miR-23a-3p and hsa-miR-130a-3p were closely related to the prognosis of GC. ZFPM2 may serve as a potential molecular marker and therapeutic target for GC. ECM receptor interactions and metabolic abnormalities play a critical role in the GC progression.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 569-569 ◽  
Author(s):  
Claudia Schoch ◽  
Wolfgang Kern ◽  
Alexander Kohlmann ◽  
Wolfgang Hiddemann ◽  
Sylvia Merk ◽  
...  

Abstract Acute myeloid leukemia (AML) is a heterogeneous group of diseases with varying clinical outcome. So far the karyotype of the leukemic blasts as well as molecular genetic abnormalities - both abnormalities on the genomic level - have been proven to be strong prognostic markers. However, even in genetically well defined subgroups clinical outcome is not uniform and a large proportion of AML shows genetic abnormalities of yet unknown prognostic significance. Here we addressed the question whether gene expression profiles are associated with clinical outcome independent of the known genomic abnormalities. Therefore, gene expression analyses were performed using Affymetrix U133A+B oligonucleotide microarrays in a total of 403 AML treated uniformly in the AMLCG studies. This cohort was divided randomly into a training set (n=269) and a test set (n=134). The training set included 18 cases with t(15;17), 22 cases with t(8;21), 29 cases with inv(16), 14 cases with 11q23/MLL-rearrangement, 19 with complex aberrant karyotype and 167 cases with normal karyotype or “other” chromosome aberrations. The respective data for the test set were: 10 t(15;17), 8 t(8;21), 11 inv(16), 8 11q23/MLL, 19 cases with complex aberrant karyotype and 78 with normal karyotype or “other” chromosome aberrations. Based on the clinical outcome the training cohort was divided into 4 equally large subgroups. We trained support vector machines (SVM) with the training set and classified the cases of the test set with the respective most discriminating genes. Next a Kaplan-Meier analysis was performed with the test set cases assigned to prognostic groups 1 to 4 according to SVM classification. Based on the expression level of 100 genes group 1 showed an overall survival rate of 57% at 3 years. 31 of 134 (23%) patients were assigned to this favorable subgroup. They belonged to the following cytogenetic subgroups: t(15;17) n=6, t(8;21) n=4, inv(16) n=3, 11q23/MLL n=4, complex aberrant karyotype n=1 and normal karyotype or “other” chromosome aberration n=13. The overall survival rate of groups 2, 3, and 4 did not differ significantly (17%, 21%, and 19% at 3 years). Among the genes highly expressed in the favorable group were MPO and the transcription factor ATBF1, which regulates CCND1. The unfavorable groups were characterized by a higher expression of the transcription factors ETS2, RUNX1, TCF4, and FOXC1. Interestingly, 10 of the top 40 differentially expressed genes are involved in the TP53-CMYC-pathway with a higher expression of 9 of these in the unfavorable groups (SFRS1, TPD52, NRIP1, TFPI, UBL1, REC8L1, HSF2, ETS2 and RUNX1). In conclusion, gene expression profiling leads to the identification of prognostically important alterations of molecular pathways which have not yet been accounted for by use of cytogenetics. This approach is anticipated to help optimizing therapy for patients with AML.


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