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 SamplesWe report the effect of DKK1 treatment during culture on the length and transcriptome of embryos on day 15 of development, supporting the notion that changes early in development affect later stages of development. Overall design: Bovine embryos were produced in vitro and exposed to either 0 or 100 ng/ml DKK1 from day 5 to 7 of culture. Embryos were transferred on day 7 and recovered on day 15 for evaluation of length and transciptome
Dickkopf-related protein 1 is a progestomedin acting on the bovine embryo during the morula-to-blastocyst transition to program trophoblast elongation.
Treatment, Subject
View SamplesPrimary human macrophages with a HIF-1alpha or HIF-2alpha knockdown were pretreated with IL-10 for 16h and afterwards for 4h additionaly under hypoxi (1% O2), RNA was isolated usind the Qiagen RNAeasy Kit and cDNA synthesis wos done using Ambion WT Expression Kit. Expression was compared to si control under control conditions.
Genome-wide identification of hypoxia-inducible factor-1 and -2 binding sites in hypoxic human macrophages alternatively activated by IL-10.
Specimen part
View SamplesBackground & Aims: Ursodeoxycholic acid (UDCA) attenuates chemical and colitis-induced colon carcinogenesis in animal models. We investigated its mechanism of action on normal intestinal cells, in which carcinogenesis- or inflammation-related alterations do not interfere with the result. Methods: Alterations of gene expression were identified in Affymetrix arrays in isolated colon epithelium of mice fed with a diet containing 0.4% UDCA and were confirmed in the normal rat intestinal cell line IEC-6 by RT-PCR. The effect of the insulin receptor substrate 1 (Irs-1) expression and of ERK phosphorylation on proliferation was investigated in vitro by flow cytometry, western blotting, siRNA-mediated gene suppression or by pharmacological inhibition of the kinase activity. The ERK1-effect on Irs-1 transcription was tested in a reporter system. Results: UDCA-treatment in vivo suppressed potential pro-proliferatory genes including Irs-1 and reduced cell proliferation by more than 30%. In vitro it neutralised the proliferatory signals of IGF-1 and EGF and slowed down the cell cycle. Irs-1 transcription was suppressed due to high ERK1 activation. Both Irs-1 suppression and the persistent high ERK activation inhibited proliferation. Conversely, the decrease of phosphorylation of ERK1 (but not ERK2) or of its expression partially abrogated the inhibitory effects of UDCA. Conclusions: UDCA inhibits proliferation of intestinal epithelial cells by acting upon IGF-1 and EGF pathways and targeting ERK1 and, consequently, Irs-1. The inhibition of these pathways adds a new dimension to the physiological and therapeutic action of UDCA and, since both pathways are activated in inflammation and cancer, suggests new applications of UDCA in chemoprevention and chemotherapy.
UDCA slows down intestinal cell proliferation by inducing high and sustained ERK phosphorylation.
Specimen part, Cell line
View Samples10 days old tumor spheroids were processed for RNA isolation using the Quiagen RNeasy Micro Kit and cDNA synthesis was done using the Ambion WT Expression Kit. Wt, HIF-1 k/d and HIF-2 k/d samples were compared to each other.
HIF-2alpha-dependent PAI-1 induction contributes to angiogenesis in hepatocellular carcinoma.
Specimen part, Cell line
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 SamplesGene expression analysis was performed from microdissected small and big HRS cells, which were taken from smears of the Hodgkin cell lines
Small and big Hodgkin-Reed-Sternberg cells of Hodgkin lymphoma cell lines L-428 and L-1236 lack consistent differences in gene expression profiles and are capable to reconstitute each other.
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 Samples