The transcription factor network in Hodgkin lymphoma (HL) represents a unique composition of proteins found in no other hematopoietic cell. Among these factors, an aberrant expression of the T cell transcription factor GATA-3 is observed in the B cell-derived Hodgkin and Reed/Sternberg (HRS) tumor cells. Herein, we elucidated the regulation and function of this factor in HL
Mechanisms of aberrant GATA3 expression in classical Hodgkin lymphoma and its consequences for the cytokine profile of Hodgkin and Reed/Sternberg cells.
Cell line
View SamplesThe cellular origin of chronic lymphocytic leukemia (CLL) is debated. Transcriptome analysis of CLL and normal peripheral blood and splenic B cell subsets displayed highest similarity of CLL to mature CD5+ B cells. We identified a distinct CD5+CD27+ post-germinal center B cell subset, and revealed that immunoglobulin V gene mutated CLL are more similar to mutated CD5+ B cells, whereas unmutated CLL are more related to unmutated CD5+ B cells. Stereotyped immunoglobulin V gene rearrangements were significantly enriched among CD5+ B cells, providing further genetic evidence for a derivation of CLL from CD5+ B cells. Moreover, we identified deregulated expression patterns providing novel insights into the pathophysiology of CLL, including downregulation of EBF1 and KLF family members.
Cellular origin and pathophysiology of chronic lymphocytic leukemia.
Specimen part
View SamplesThe 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.
Analyzing primary Hodgkin and Reed-Sternberg cells to capture the molecular and cellular pathogenesis of classical Hodgkin lymphoma.
Specimen part, Cell line
View SamplesSmall 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.
Human CD30+ B cells represent a unique subset related to Hodgkin lymphoma cells.
Specimen part
View SamplesSeveral studies have described a crosstalk between the tumour cells of cHL, the Hodgkin- and Reed-Sternberg (HRS) cells, and cancer-associated fibroblasts (CAF). However, to date a deep molecular characterization of these fibroblasts is lacking. Aim of the present study therefore was a comprehensive characterization of these fibroblasts.
Fibroblasts in Nodular Sclerosing Classical Hodgkin Lymphoma Are Defined by a Specific Phenotype and Protect Tumor Cells from Brentuximab-Vedotin Induced Injury.
Disease
View SamplesNodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is an indolent lymphoma, but can transform into diffuse large B cell lymphoma (DLBCL), showing a more aggressive clinical behavior. Little is known about these cases on the molecular level. Therefore, the aim of the present study was to characterize DLBCL transformed from NLPHL (LP-DLBCL) by gene expression profiling (GEP). GEP revealed an inflammatory signature pinpointing to a specific host response. In a coculture model resembling this host response, DEV tumor cells showed an impaired growth behavior. Mechanisms involved in the reduced tumor cell proliferation included a downregulation of MYC and its target genes. Lack of MYC expression was also confirmed in 12/16 LP-DLBCL by immunohistochemistry. Furthermore, CD274/PD-L1 was upregulated in tumor cells after coculture with T cells or monocytes and its expression was validated in 12/19 cases of LP-DLBCL. Thereby, our data provide new insights into the pathogenesis of LP-DLBCL and a concrete explanation of the relatively low tumor cell content. Moreover, our results suggest that treatment of these patients with checkpoint inhibitors may enhance an already ongoing host response in these patients.
A strong host response and lack of MYC expression are characteristic for diffuse large B cell lymphoma transformed from nodular lymphocyte predominant Hodgkin lymphoma.
Specimen part
View SamplesHuman PB B cell subsets are functionally distinct and may derive from different developmental pathways, reflected by their differential gene expression profiles.
Functional capacities of human IgM memory B cells in early inflammatory responses and secondary germinal center reactions.
Specimen part
View SamplesGene expression profiles were compared between L-428 HRS cells transduced with shRNA against AP-1 transcription factor BATF3 and L-428 HRS cells transduced with a non-targeting shRNA as control.
An oncogenic axis of STAT-mediated BATF3 upregulation causing MYC activity in classical Hodgkin lymphoma and anaplastic large cell lymphoma.
Specimen part
View SamplesNodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is an indolent lymphoma, but can transform into diffuse large B cell lymphoma (DLBCL), showing a more aggressive clinical behavior. Little is known about these cases on the molecular level. Therefore, the aim of the present study was to characterize DLBCL transformed from NLPHL
A strong host response and lack of MYC expression are characteristic for diffuse large B cell lymphoma transformed from nodular lymphocyte predominant Hodgkin lymphoma.
Specimen part, Cell line
View SamplesIn a supervised principal component analysis, histiocytes from TCHRBCL were most closely related to epithelioid cells from NLPHL, with both types of cells expressing genes related to proinflammatory and regulatory macrophage activity.
Macrophages in T cell/histiocyte rich large B cell lymphoma strongly express metal-binding proteins and show a bi-activated phenotype.
Specimen part
View Samples