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GSE40160
Homo sapiens
10 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The pathogenesis of classical Hodgkin lymphoma (cHL), the most common lymphoma in the young, is still enigmatic, largely because its Hodgkin and Reed-Sternberg (HRS) tumor cells are rare in the involved lymph node and therefore difficult to analyze. Here, by overcoming this technical challenge and performing for the first time a genome-wide transcriptional analysis of microdissected HRS cells in comparison to other B-cell lymphomas, cHL lines and normal B-cell subsets, we show that they differ extensively from the usually studied cHL cell lines, that the lost B-cell identity of cHLs is not linked to the acquisition of a plasma cell-like gene expression program, and that Epstein-Barr virus infection of HRS cells has a minor transcriptional influence on the established cHL clone. Moreover, although cHL appears a distinct lymphoma entity overall, HRS cells of its histological subtypes diverged in their similarity to other related lymphomas. Unexpectedly, we identified two molecular subgroups of cHL associated to differential strengths of the transcription factor activity of the NOTCH1, MYC and IRF4 proto-oncogenes. Finally, HRS cells display deregulated expression of several genes potentially highly relevant to lymphoma pathogenesis, including silencing of the apoptosis-inducer BIK and of INPP5D, an inhibitor of the PI3K-driven oncogenic pathway.
Publication Title
Analyzing primary Hodgkin and Reed-Sternberg cells to capture the molecular and cellular pathogenesis of classical Hodgkin lymphoma.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Small subsets of B cells in the germinal center (GC) and in extrafollicular regions of lymph nodes express the activation marker CD30. Very little is known about the specific features of these cells and their relationship to the CD30-expressing Hodgkin and Reed/Sternberg (HRS) cells of Hodgkin lymphoma. Phenotypic and immunoglobulin V gene analyses revealed that CD30+ GC B lymphocytes represent typical GC B cells, and that CD30+ non-GC B cells are mostly post-GC B cells. However, despite these seemingly distinct identities, both CD30+ subsets share an unexpectedly large overlap in specific transcriptome patterns, and are strikingly different from bulk GC B cells and classical memory and plasma cells, respectively. A main common feature of these CD30+ B cells is a strong MYC signature. CD30+ GC B cells appear to represent the recently described MYC+ GC B cell subset of recirculating centrocytes at the stage of centroblast transition. CD30+ non-GC B cells rather represent highly activated and proliferating memory B cells, differentiating into plasma cells. Notably, CD30+ B cells were more similar in their transcriptome patterns to HRS cells than any other B cell subset investigated, suggesting that HRS cells may either derive from CD30+ B cells or acquired a similar activation signature. In comparison to CD30+ B cells and other lymphomas, HRS cells show a remarkable downregulation of genes regulating cell cycle, genomic stability and polyploidity, providing a potential explanation for the genomic instability and multinuclearity of HRS cells.
Publication Title
Human CD30+ B cells represent a unique subset related to Hodgkin lymphoma cells.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 64 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The pathogenesis of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) and its relationship to other lymphomas are largely unknown. This is partly due to the technical challenge of analyzing its rare neoplastic L&H cells, which are dispersed in an abundant non-neoplastic cellular microenvironment. We performed a genome-wide expression study of microdissected lymphocytic and histiocytic (L&H) lymphoma cells in comparison to normal and other malignant B cells, which indicates a relationship of L&H cells to and/or origin from germinal center B cells at transition to memory B cells. L&H cells show a surprisingly high similarity to the tumor cells of T cell-rich B cell lymphoma and classical Hodgkin lymphoma, a partial loss of their B cell phenotype and deregulation of many apoptosis-regulators and putative oncogenes. Importantly, L&H cells are characterized by constitutive NF-B activity and aberrant ERK signaling. Thus, these findings shed new light on the nature of L&H cells, revealed several novel pathogenetic mechanisms in NLPHL, and may help in differential diagnosis and lead to novel therapeutic strategies.
Publication Title
Origin and pathogenesis of nodular lymphocyte-predominant Hodgkin lymphoma as revealed by global gene expression analysis.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 20 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Hairy cell leukemia (HCL) shows unique clinico-pathological and biological features. HCL responds well to purine analogues but relapses are frequent and novel therapies are required. BRAF-V600E is the key driver mutation in HCL and distinguishes it from other B-cell lymphomas, including HCL-like leukemias/lymphomas (HCL-variant and splenic marginal zone lymphoma). The kinase-activating BRAF-V600E mutation also represents an ideal therapeutic target in HCL. Here, we investigated the biological and therapeutic importance of the activated BRAF-MEK-ERK pathway in HCL by exposing in vitro primary leukemic cells purified from 26 patients to clinically available BRAF (Vemurafenib; Dabrafenib) or MEK (Trametinib) inhibitors. Results were validated in vivo in samples from Vemurafenib-treated HCL patients within a phase-2 clinical trial. BRAF and MEK inhibitors caused, specifically in HCL (but not HCL-like) cells, marked MEK/ERK dephosphorylation, silencing of the BRAF-MEK-ERK pathway transcriptional output, loss of the HCL-specific gene expression signature, downregulation of the HCL markers CD25, TRAP and cyclin-D1, smoothening of leukemic cells' hairy surface, and, eventually, apoptosis. Apoptosis was partially blunted by co-culture with bone marrow stromal cells antagonizing MEK-ERK dephosphorylation. This protective effect could be counteracted by combined BRAF and MEK inhibition. Our results strongly support and inform the clinical use of BRAF and MEK inhibitors in HCL.
Publication Title
BRAF inhibitors reverse the unique molecular signature and phenotype of hairy cell leukemia and exert potent antileukemic activity.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples- Homo sapiens
- 63 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Anaplastic large cell lymphoma (ALCL) is a main type of T cell lymphomas and comprises three distinct entities: systemic ALK+, systemic ALK- and cutaneous ALK- ALCL. Little is known about their pathogenesis and their cellular origin, and morphological and immunophenotypical overlap exists between ALK- ALCL and classical Hodgkin lymphoma (cHL). We conducted gene expression profiling of microdissected lymphoma cells of ALK+ and ALK- systemic ALCL, cutaneous ALCL and cHL, and of eight subsets of normal T and NK cells. The analysis supports a derivation of ALCL from activated T cells, but the lymphoma cells acquired a gene expression pattern hampering an assignment to a CD4+, CD8+ or CD30+ T cell origin. Indeed, ALCL display a general down-modulation of T cell characteristic molecules. All ALCL types show significant expression of NFB target genes and upregulation of genes involved in oncogenesis (e.g. EZH2). Surprisingly few genes are differentially expressed between systemic and cutaneous ALK- ALCL despite their different clinical behaviour, and between ALK- ALCL and cHL despite their different cellular origin. ALK+ ALCL are characterized by expression of genes regulated by pathways constitutively activated by ALK. This study provides multiple novel insights into the molecular biology and pathogenesis of ALCL.
Publication Title
Gene expression profiling of isolated tumour cells from anaplastic large cell lymphomas: insights into its cellular origin, pathogenesis and relation to Hodgkin lymphoma.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 77 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Approximately one third of acute myeloid leukemias (AMLs) are characterized by aberrant cytoplasmic localization of Nucleophosmin (NPMc+ AML), consequent to mutations in the NPM putative nucleolar localization signal. These events are mutually exclusive with the major AML-associated chromosomal rearrangements, and are frequently associated with normal karyotype, Fms-like tyrosine kinase (FLT3) mutations and multilineage involvement. We report the gene expression profiles of 78 de novo AMLs (72 with normal karyotype; 6 with non-major chromosomal abnormalities) that were characterized for the subcellular localization and mutation status of NPM. Unsupervised clustering clearly separated NPMc+ from NPMc- AMLs, regardless of the presence of FLT3 mutations or non-major chromosomal rearrangements, supporting the concept that NPMc+ AML represents a distinct entity. The molecular signature of NPMc+ AML includes up-regulation of several genes putatively involved in the maintenance of a stem cell phenotype, suggesting that NPMc+ AML may derive from a multipotent hematopoietic progenitor.
Publication Title
Acute myeloid leukemia bearing cytoplasmic nucleophosmin (NPMc+ AML) shows a distinct gene expression profile characterized by up-regulation of genes involved in stem-cell maintenance.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 2 Downloadable Samples
Illumina HiSeq 2000
Description
Natural CD4+FOXP3+ regulatory T (Treg) cells constitute a unique T-cell lineage that plays a pivotal role in maintaining immune homeostasis and immune tolerance. Recent studies provide evidence for the heterogeneity and plasticity of the Treg cell lineage. However, the fate of human Treg cells after loss of FOXP3 expression and the underlying epigenetic mechanisms remain to be fully elucidated. Here, we compared gene expression profiles and histone methylation status on two histone H3 lysine residues (H3K4me3 and H3K27me3) of expanded FOXP3+ and corresponding FOXP3-losing Treg cells. DGE assay showed that human Treg cells down-regulated Treg signature genes, whereas up-regulated a set of Th lineages-associated genes, especially for Th2, such as GATA3, GFI1 and IL13, after in vitro expansion. Furthermore, we found that reprogramming of Treg cells was associated with histone modifications, as shown by decreased abundance of permissive H3K4me3 within down-regulated Treg signature genes, such as FOXP3, CTLA4 and LRRC32 loci, although with no significant changes in H3K27me3 modification. Thus, our results indicate that human Treg cells could convert into a Th-like cells upon in vitro expansion, displaying a gene expression signature dominated by Th2 lineage associated genes, and the histone methylation might contribute to such conversion. Overall design: mRNA profiles of in-vitro-expanded FOXP3+ Treg and FOXP3-losing Treg cells generated by deep sequencing.
Publication Title
Histone methylation mediates plasticity of human FOXP3(+) regulatory T cells by modulating signature gene expressions.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 26 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Anaplastic Large Cell Lymphoma (ALCL) is a clinical and biological heterogeneous disease including ALK positive and ALK negative systemic forms. To discover biomarkers and/or genes involved in ALK negative ALCL pathogenesis, we applied the Cancer Outlier Profile Analysis (COPA) algorithm to a gene expression profiling data set including 249 cases of T-NHLs and normal T-cells. Ectopic co-expression of ERBB4 and COL29A1 genes was detected in 24% of ALK negative ALCL patients. RNA sequencing and 5'RNA Ligase Mediated Rapid Amplification of cDNA Ends (RLM-RACE) identified two novel ERBB4 truncated transcripts, displaying intronic Transcription Starting Sites. ERBB4 expression was confirmed at protein level by western blotting and immunohistochemistry. Moreover, by luciferase assays we defined that the expression of ERBB4 aberrant transcripts is promoted by endogenous intronic Long Terminal Repeats (LTRs). In conclusion, we identified a new subclass of ALK negative ALCL characterized by aberrant expression of ERBB4 truncated transcripts carrying intronic 5'UTRs.
Publication Title
Identification of a new subclass of ALK-negative ALCL expressing aberrant levels of ERBB4 transcripts.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 2 Downloadable Samples
- Illumina HiSeq 2000
Description
Hepatitis B virus (HBV) is a hepatotropic virus that can regulate many host cellular gene expressions participating in the HBV life cycle, liver inflammation and hepatocellular injury. However, the underlying mechanism of differential gene expression is not understood. We report here a genome-wide analysis of histone methylation on two histone H3 lysine residues (H3K4me3 and H3K27me3) and gene expression profiles in HepG2 and HepG2.2.15 cells. We found that specific correlation exists between gene expression and the amounts of H3K4me3 (positive correlation) and H3K27me3 (negative correlation) across the gene body. These correlations displayed three distinct modes (repressive, active and poised), reflecting different functions of these genes in the HBV life cycle, liver inflammation and hepatocellular injury. Furthermore, a permissive chromatin state of each gene was established by a combination of different histone modifications. Our findings reveal a complex regulation by histone methylation in differential gene expression and suggest that histone methylation may be responsible for the HBV life cycle, liver inflammation and hepatocellular injury induced by HBV. Overall design: A large-scale analysis of gene expression of 2 different cell types (HepG2, HepG2.2.15) using a digital gene expression (DGE) tag profiling approach.
Publication Title
Telbivudine treatment corrects HBV-induced epigenetic alterations in liver cells of patients with chronic hepatitis B.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 24 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Among acute myeloid leukemias (AML) with normal karyotype (CN-AML), NPM1 and CEBPA mutations define WHO provisional entities accounting for ~60% of cases, but the remaining ~40% remains poorly characterized. By whole exome-sequencing (WES) of one CN-AML patient lacking mutations in NPM1, CEBPA, FLT3, MLL-PTD and IDH1, we newly identified a clonal somatic mutation in BCOR (BCL6 co-repressor), a gene located in chromosome X. Further analyses showed that BCOR mutations occurred in 11/262 (4.2%) CN-AML cases and represented a substantial fraction (14/82, 17.1%) of CN-AML patients showing the same genetic background as the index patient subjected to WES.
Publication Title
Whole-exome sequencing identifies somatic mutations of BCOR in acute myeloid leukemia with normal karyotype.
Sample Metadata Fields
Disease
View Samples