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.
Origin and pathogenesis of nodular lymphocyte-predominant Hodgkin lymphoma as revealed by global gene expression analysis.
No sample metadata fields
View SamplesAnaplastic 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.
Gene expression profiling of isolated tumour cells from anaplastic large cell lymphomas: insights into its cellular origin, pathogenesis and relation to Hodgkin lymphoma.
Specimen part
View SamplesThe molecular regulation of zygotic genome activation (ZGA) in mammals remains poorly understood. Primed mouse embryonic stem cells contain a rare subset of “2C-like” cells that are epigenetically and transcriptionally similar to the two cell embryo and thus represent an ideal system for studying ZGA transcription regulation. Recently, the transcription factor Dux, expressed exclusively in the minor wave of ZGA, was described to activate many downstream ZGA transcripts. However, it remains unknown what upstream maternal factors initiate ZGA either in a Dux dependent or independent manner. Here we performed a candidate-based overexpression screen, identifying, amongst others, Developmental Pluripotency Associated 2 (Dppa2) and 4 (Dppa4) as positive regulators of 2C-like cells and ZGA transcription. In the germ line, promoter DNA demethylation coincides with upregulation of Dppa2 and Dppa4 which remain expressed until E7.5 when their promoters are remethylated. Furthermore, Dppa2 and Dppa4 are also expressed during iPSC reprogramming at the time 2C-like ZGA transcription transiently peaks. Through a combination of overexpression, knockdown, knockout and rescue experiments, together with transcriptional analyses, we show that Dppa2 and Dppa4 directly regulate the 2C-like cell population and associated transcripts, including Dux and the Zscan4 cluster. Importantly, we tease apart the molecular hierarchy in which the 2C-like transcriptional program is initiated and stabilised. Dppa2 and Dppa4 require Dux to initiate 2C-like ZGA transcription, suggesting they act upstream by directly regulating Dux. Supporting this, ChIP-seq analysis revealed Dppa2 and Dppa4 bind to the Dux promoter and gene body and drive its expression. Zscan4c is also able to induce 2C-like cells in wild type cells, but, in contrast to Dux, can no longer do so in Dppa2/4 double knockout cells, suggesting it may act to stabilise rather than drive the transcriptional network. Our findings suggest a model in which Dppa2/4 binding to the Dux promoter leads to Dux upregulation and activation of the 2C-like transcriptional program which is subsequently reinforced by Zscan4c. Overall design: RNA sequencing of screen hits (3 biological replicates of GFP+ and GFP- sorted cells for each of 12 candidates).
Dppa2 and Dppa4 directly regulate the Dux-driven zygotic transcriptional program.
Specimen part, Cell line, Subject
View SamplesThe molecular regulation of zygotic genome activation (ZGA) in mammals remains poorly understood. Primed mouse embryonic stem cells contain a rare subset of “2C-like” cells that are epigenetically and transcriptionally similar to the two cell embryo and thus represent an ideal system for studying ZGA transcription regulation. Recently, the transcription factor Dux, expressed exclusively in the minor wave of ZGA, was described to activate many downstream ZGA transcripts. However, it remains unknown what upstream maternal factors initiate ZGA either in a Dux dependent or independent manner. Here we performed a candidate-based overexpression screen, identifying, amongst others, Developmental Pluripotency Associated 2 (Dppa2) and 4 (Dppa4) as positive regulators of 2C-like cells and ZGA transcription. In the germ line, promoter DNA demethylation coincides with upregulation of Dppa2 and Dppa4 which remain expressed until E7.5 when their promoters are remethylated. Furthermore, Dppa2 and Dppa4 are also expressed during iPSC reprogramming at the time 2C-like ZGA transcription transiently peaks. Through a combination of overexpression, knockdown, knockout and rescue experiments, together with transcriptional analyses, we show that Dppa2 and Dppa4 directly regulate the 2C-like cell population and associated transcripts, including Dux and the Zscan4 cluster. Importantly, we tease apart the molecular hierarchy in which the 2C-like transcriptional program is initiated and stabilised. Dppa2 and Dppa4 require Dux to initiate 2C-like ZGA transcription, suggesting they act upstream by directly regulating Dux. Supporting this, ChIP-seq analysis revealed Dppa2 and Dppa4 bind to the Dux promoter and gene body and drive its expression. Zscan4c is also able to induce 2C-like cells in wild type cells, but, in contrast to Dux, can no longer do so in Dppa2/4 double knockout cells, suggesting it may act to stabilise rather than drive the transcriptional network. Our findings suggest a model in which Dppa2/4 binding to the Dux promoter leads to Dux upregulation and activation of the 2C-like transcriptional program which is subsequently reinforced by Zscan4c. Overall design: RNA-sequencing of ESCs treated with control, Dppa2 or Dppa4 siRNAs for 4 days.
Dppa2 and Dppa4 directly regulate the Dux-driven zygotic transcriptional program.
Specimen part, Cell line, Subject
View SamplesThe molecular regulation of zygotic genome activation (ZGA) in mammals remains poorly understood. Primed mouse embryonic stem cells contain a rare subset of “2C-like” cells that are epigenetically and transcriptionally similar to the two cell embryo and thus represent an ideal system for studying ZGA transcription regulation. Recently, the transcription factor Dux, expressed exclusively in the minor wave of ZGA, was described to activate many downstream ZGA transcripts. However, it remains unknown what upstream maternal factors initiate ZGA either in a Dux dependent or independent manner. Here we performed a candidate-based overexpression screen, identifying, amongst others, Developmental Pluripotency Associated 2 (Dppa2) and 4 (Dppa4) as positive regulators of 2C-like cells and ZGA transcription. In the germ line, promoter DNA demethylation coincides with upregulation of Dppa2 and Dppa4 which remain expressed until E7.5 when their promoters are remethylated. Furthermore, Dppa2 and Dppa4 are also expressed during iPSC reprogramming at the time 2C-like ZGA transcription transiently peaks. Through a combination of overexpression, knockdown, knockout and rescue experiments, together with transcriptional analyses, we show that Dppa2 and Dppa4 directly regulate the 2C-like cell population and associated transcripts, including Dux and the Zscan4 cluster. Importantly, we tease apart the molecular hierarchy in which the 2C-like transcriptional program is initiated and stabilised. Dppa2 and Dppa4 require Dux to initiate 2C-like ZGA transcription, suggesting they act upstream by directly regulating Dux. Supporting this, ChIP-seq analysis revealed Dppa2 and Dppa4 bind to the Dux promoter and gene body and drive its expression. Zscan4c is also able to induce 2C-like cells in wild type cells, but, in contrast to Dux, can no longer do so in Dppa2/4 double knockout cells, suggesting it may act to stabilise rather than drive the transcriptional network. Our findings suggest a model in which Dppa2/4 binding to the Dux promoter leads to Dux upregulation and activation of the 2C-like transcriptional program which is subsequently reinforced by Zscan4c. Overall design: RNA-sequencing of Dppa2 and/or Dppa4 knockout ESCs.
Dppa2 and Dppa4 directly regulate the Dux-driven zygotic transcriptional program.
Specimen part, Cell line, Subject
View SamplesA complex interplay between ethylene, ETP1/ETP2 F-box proteins, and degradation of EIN2 is essential for triggering ethylene responses in plants.
Interplay between ethylene, ETP1/ETP2 F-box proteins, and degradation of EIN2 triggers ethylene responses in Arabidopsis.
Age, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The synthetic glucocorticoids prednisolone and dexamethasone regulate the same genes in acute lymphoblastic leukemia cells.
Specimen part, Cell line, Treatment
View SamplesBackground: Glucocorticoids (GCs) cause apoptosis in malignant cells of lymphoid lineage by transcriptionally regulating a plethora of genes. As a result, GCs are included in almost all treatment protocols for lymphoid malignancies, particularly childhood acute lymphoblastic leukemia (chALL). The most commonly used synthetic GCs in the clinical setting are prednisolone and dexamethasone. While the latter has a higher activity and more effectively reduces the tumor load in patients, it is also accompanied by more serious adverse effects than the former. Whether this difference might be explained by regulation of different genes by the two GCs has never been addressed.
The synthetic glucocorticoids prednisolone and dexamethasone regulate the same genes in acute lymphoblastic leukemia cells.
Specimen part, Cell line
View SamplesBackground: Glucocorticoids (GCs) cause apoptosis in malignant cells of lymphoid lineage by transcriptionally regulating a plethora of genes. As a result, GCs are included in almost all treatment protocols for lymphoid malignancies, particularly childhood acute lymphoblastic leukemia (chALL). The most commonly used synthetic GCs in the clinical setting are prednisolone and dexamethasone. While the latter has a higher activity and more effectively reduces the tumor load in patients, it is also accompanied by more serious adverse effects than the former. Whether this difference might be explained by regulation of different genes by the two GCs has never been addressed.
The synthetic glucocorticoids prednisolone and dexamethasone regulate the same genes in acute lymphoblastic leukemia cells.
Specimen part, Cell line, Treatment
View SamplesOrganoids derived from human pluripotent stem cells recapitulate the early three-dimensional organization of human brain, but whether they establish the epigenomic and transcriptional programs essential for brain development is unknown. We compared epigenomic and gene regulatory features in cerebral organoids and human fetal brain, using genome-wide, base resolution DNA methylome and transcriptome sequencing. Transcriptomic dynamics in organoids faithfully modeled gene expression trajectories in early-to-mid human fetal brains. We found that early non-CG methylation accumulation at super-enhancers in both fetal brain and organoids marks forthcoming transcriptional repression in the fully developed brain. 74% of 35,627 demethylated regions identified during organoid differentiation overlapped with fetal brain regulatory elements. Interestingly, pericentromeric repeats showed widespread demethylation in multiple types of in vitro human neural differentiation models but not in fetal brain. Our study reveals that organoids recapitulate many epigenomic features of mid-fetal human brain and also identified novel non-CG methylation signatures of brain development. Overall design: MethylC-seq and RNA-seq of Cerebral Organoids differentiation
Cerebral Organoids Recapitulate Epigenomic Signatures of the Human Fetal Brain.
No sample metadata fields
View Samples