Project description:Proteogenomic analysis and genomic profiling, RNA-sequencing, and mass spectrometry-based analysis of High hyperdiploid childhood acute lymphoblastic leukemia.
Project description:T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LL) and are often thought to represent a spectrum of a single disease. The malignant cells in T-ALL and T-LL are morphologically indistinguishable, and they share the expression of common cell surface antigens and cytogenetic characteristics. However, despite these similarities, differences in the predominant sites of disease in T-ALL and T-LL are observed. To determine if underlying biological distinctions may potentially contribute to some of these differences, we analyzed the global gene expression profiles of malignant T-cell precursors in ten T-ALL and nine T-LL using DNA arrays. Ten additional B-precursor ALL bone marrow samples, were used in a separate analysis. <br><br> Note that files GSM27087.txt and GSM27088.txt are identical as downloaded from GEO.
Project description:Normal early human B-cells development from lymphoid progenitors in the bone marrow is dependent upon instructions from elements in that microenvironment which include stromal cells as well as extracellular matrix and factors secreted by these cells. Glycosylation is thought to play a key role in such interactions. The sialyltransferase ST6Gal1, with high expression in specific hematopoietic cell types, is the only enzyme thought to catalyze the terminal addition of sialic acids in an a2-6-linkage to galactose on N-glycans in such cells. Expression of ST6Gal1 increases as mouse B cells undergo normal B-lineage differentiation. B-cell precursor acute lymphoblastic leukemias (BCP-ALL) with differentiation arrest at various stages of early B-cell development have widely different expression levels of ST6GALl1 at diagnosis, with high ST6Gal1 in some relapses. We analyzed the consequences of increased ST6Gal1 expression in a diagnosis sample using lentiviral transduction of ST6Gal1 into US7 cells which have a relatively low level of ST6Gal1 expression. Controls were transduced with an empty vector. Gene expression analysis using RNA-seq showed a surprisingly large number of genes with significant differential expression, of which around 60% showed increased transcript levels, in the ST6Gal1 overexpressing BCP-ALL cells.
Project description:Proteogenomic analysis and genomic profiling, RNA-sequencing, and mass spectrometry-based analysis of High hyperdiploid childhood acute lymphoblastic leukemia.
Project description:Interleukin-7 receptor α (encoded by IL7R) is essential for lymphoid development. Whether acute lymphoblastic leukemia (ALL)-related IL7R gain-of-function mutations can trigger leukemogenesis remains unclear. Here, we demonstrate that lymphoid-restricted mutant IL7R, expressed at physiological levels in conditional knock-in mice, establishes a pre-leukemia stage in which B-cell precursors display self-renewal ability, initiating precursor B-ALL that resembles PAX5 P80R or Ph-like human leukemia. Full transformation associates with transcriptional upregulation of oncogenes such as Myc or Bcl2, downregulation of tumor suppressors such as Ikzf1 or Arid2, and major IL-7R signaling upregulation (involving both JAK/STAT5 and PI3K/mTOR), required for leukemia cell viability. Accordingly, maximal signaling drives full penetrance and early leukemia onset in homozygous IL7R mutant animals. Notably, we identify 2 transcriptional subgroups in mouse and human Ph-like ALL, and show that dactolisib and sphingosine-kinase inhibitors are novel treatment avenues for IL-7R-related cases. Our model, a unique resource to explore the pathophysiology and therapeutic vulnerabilities of B-ALL, demonstrates that IL7R can initiate this malignancy.
Project description:B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is a heterogeneous disease that can be subdivided according to primary recurrent genetic abnormalities that are strongly associated with characteristic biological and clinical features. The detection of these abnormalities can facilitate diagnosis, risk stratification, and targeted therapy. We identified an unexpectedly high incidence of fusion genes involving ZNF384 genes, including TCF3-ZNF384, EP300-ZNF384, and CREBBP-ZNF384, in BCP-ALL of our cohort. We therefore used microarrays to evaluate the gene-expression characteristics of BCP-ALL harboring ZNF384-related fusion genes and compared with those of BCP-ALL with other types of conventional genetic abnormality.
Project description:B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cells reside in the bone marrow microenvironment, where they are protected against chemotherapeutic agents. Mesenchymal stromal cells (MSCs) are key components of this supporting framework. The present study aimed to unravel whether MSCs derived from pediatric BCP-ALL patients (leukemic MSCs) differ from MSCs derived from healthy pediatric donors (control-MSCs). Therefore, we studied their gene expression profiles after 40 hours of co-culture with primary B-cell precursor acute lymphoblastic leukemia cells. MSCs were sorted using fluorescence-activated cell sorting (FACS).
Project description:We used microarrays to detail the constitutive global programme of gene expression of a series of acute lymphoblastic leukemia (ALL) cell lines. 6 B-cell precursor ALL and 7 T-cell ALL cell lines were investigated.
Project description:Gene expression profiling (GEP) can reveal characteristic signatures associated with distinct biologic subtypes of acute lymphoblastic leukemia (ALL). We performed GEP on Down syndrome (DS) and comparison non-Down syndrome (NDS) ALL cases to identify biologic differences between these groups. Ficoll-enriched, cryopreserved diagnostic bone marrow samples were obtained from patients with newly diagnosed B-precursor acute lymphoblastic leukemia.
Project description:Overexpression of the transcription factor RUNX1 was studied in Nalm-6 precursor B acute lymphoblastic leukemia cells. The active enhancer histone marker H3K27ac and RUNX1 were measured using ChIP-seq. The effect on gene expression was analyzed using single cell RNA-sequencing.