DLBCLR_RNAseq - samples
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ABSTRACT:
PROVIDER: EGAD00001011309 | EGA |
REPOSITORIES: EGA
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Project description:Differentiation of antigen-activated B cells into pro-proliferative germinal center (GC) B cells depends on the activity of the transcription factors MYC and BCL6, and the epigenetic writers DOT1L and EZH2. GCB-like Diffuse Large B Cell Lymphomas (GCB-DLBCLs) arise from GC B cells and closely resemble their cell of origin. Given the dependency of GC B cells on DOT1L and EZH2, we investigated the role of these epigenetic regulators in GCB-DLBCL cell lines and observed that GCB-DLBCLs synergistically depend on the combined activity of DOT1L and EZH2. Mechanistically, inhibiting both enzymes led to enhanced derepression of PRC2 target genes compared to EZH2 single treatment, along with the derepression of BCL6 target genes and suppression of MYC target genes. The sum of all these alterations results in a ‘cell identity crisis,’ wherein GCB-DLBCLs lose their pro-proliferative GC identity and partially undergo plasma cell differentiation, a state associated with poor survival. In support of this model, combined epi-drugging of DOT1L and EZH2 prohibited the outgrowth of human GCB-DLBCL xenografts in vivo. We conclude that the malignant behavior of GCB-DLBCLs strongly depends on DOT1L and EZH2 and that combined targeting of both epigenetic writers may provide an alternative differentiation-based treatment modality for GCB-DLBCL.
2025-10-14 | PXD056212 | Pride
Project description:We performed DNA methylation (HELP) and gene expression profiling in 69 samples of diffuse large B cell lymphoma (DLBCL). First, by gene expression, two molecular subtypes of DLBCL termed as germinal center B cell-like (GCB) and activated B cell-like (ABC) DLBCL were assigned to the 69 DLBCL cases. Then, we performed supervised analysis using HELP data and defined DNA methylation signature differentiating 2 subgroups of DLBCLs. Keywords: DNA methylation profiling
2010-09-03 | GSE23967 | GEO
Project description:We performed DNA methylation (HELP) and gene expression profiling in 69 samples of diffuse large B cell lymphoma (DLBCL). First, by gene expression, two molecular subtypes of DLBCL termed as germinal center B cell-like (GCB) and activated B cell-like (ABC) DLBCL were assigned to the 69 DLBCL cases. Then, we performed supervised analysis using HELP data and defined DNA methylation signature differentiating 2 subgroups of DLBCLs. Keywords: DNA methylation profiling The retrospective study included DNA extracted from 69 clinical samples. [This Series represents the DNA methylation profiling component of the study.]
2010-09-03 | E-GEOD-23967 | biostudies-arrayexpress
Project description:B cell receptor (BCR) signaling has emerged as a therapeutic target in B cell lymphomas, but the precise deployment of inhibitors to target oncogenic BCR signaling requires detailed knowledge of the signaling cascades that the BCR triggers in individual tumors. Here, we have used CRISPR-Cas9 screens to investigate whether the ABC and GCB molecular subtypes of diffuse large B cell lymphoma (DLBCL) utilize distinct BCR signaling modes to sustain their proliferation and survival. Constitutive germinal center (GC) BCR signaling in GCB DLBCLs requires the BCR, CD19 and SYK engaging PI(3) kinase for survival. In ABC DLBCLs with oncogenic mutations in the BCR and MYD88, a novel BCR-TLR9-MYD88 signaling supercomplex is assembled on endolysosomal membranes that engages NF-kB. Our data explain why this subset of ABC DLBCL tumors respond frequently to ibrutinib, an inhibitor of BCR-dependent NF- kB activation, while GCB DLBCLs are insensitive, and thus provide a roadmap for the rational development of BCR pathway inhibitors in molecular subtypes of DLBCL.
2018-05-01 | GSE99276 | GEO
Project description:<p>Diffuse large B-cell lymphoma (DLBCL), the most common lymphoid malignancy in adults, is a clinically and genetically heterogenous disease that is further classified into transcriptionally defined activated B-cell (ABC) and germinal center B-cell (GCB) subtypes. Here, we describe a comprehensive genetic analysis of DLBCLs that identifies low-frequency alterations, captures recurrent mutations, copy number alterations (CNAs) and structural variants (SVs) and characterizes coordinate genetic signatures in 304 primary DLBCLs with available outcome data. We integrated these genetic drivers using consensus clustering and identified 5 robust DLBCL subsets, including a previously unrecognized group of low-risk ABC-DLBCLs of extrafollicular/marginal zone origin; 2 distinct subsets of GCB-DLBCLs with different outcomes and targetable alterations; and an ABC/GCB-independent group with biallelic inactivation of TP53, CDKN2A loss and associated genomic instability. The genetic features of the newly identified subsets, their mutational signatures and the temporal ordering of identified alterations provide new insights into DLBCL pathogenesis. The coordinate genetic signatures also predict outcome independent of the clinical International Prognostic Index and suggest new combination treatment strategies. More broadly, these studies provide a roadmap for an actionable DLBCL classification. </p>
| phs000450 | dbGaP
Project description:Multi-agent chemotherapy still represents the first-line standard-of-care treatment for diffuse large B-cell lymphoma (DLBCL), the most common form of lymphoma in adults. However, the clinicopathological and molecular heterogeneity of DLBCLs poses a major challenge in their successful therapy. At least two major subtypes, i.e. germinal center B-cell-like (GCB) and the aggressive activated B-cell-like (ABC) DLBCL, which differ both in their gene expression profile and in their mutation patterns, have been identified. Here we demonstrate a broad inhibitory effect of dimethyl fumarate (DMF) on the outgrowth of both DLBCL subtypes, even though the molecular basis for its efficacy differs between GCB and ABC DLBCL. Due to high expression of arachidonate 5-lipoxygenase in concert with low glutathione and glutathione peroxidase 4 levels, DMF induced lipid peroxidation and thus ferroptotic cell death in GCB DLBCL. In contrast, in ABC DLBCL inhibition of NF-κB and STAT3 activity essentially contributed to DMF-dependent cytotoxicity. Interestingly, the BCL-2 specific BH3 mimetic ABT-199 or an inhibitor of the ferroptosis suppressor protein 1 synergized with DMF treatment in inducing cell death in DLBCL cell lines. Collectively, our findings identify the established and approved drug DMF as a promising novel therapeutic option in the treatment of both GCB and ABC DLBCL.
2021-07-01 | GSE164267 | GEO
Project description:Primary bone diffuse large B-cell lymphoma (PB-DLBCL) is a rare extranodal lymphoma subtype. This retrospective study elucidates the currently unknown genetic background of a large clinically well-annotated cohort of DLBCL with osseous localizations (O-DLBCL), including PB-DLBCL. 103 O-DLBCL patients were included and compared with 63 (extra)nodal non-osseous (NO)-DLBCLs with germinal center B-cell phenotype (NO-DLBCL-GCB). Cell-of-origin (COO) was determined by immunohistochemistry and gene-expression-profiling (GEP) using (extended)-NanoString/Lymph2Cx. Mutational profiles were identified with targeted next-generation deep-sequencing, including 52 B-cell lymphoma-relevant genes. O-DLBCLs, including 34 PB-DLBCL, were predominantly classified as GCB-phenotype based on immunohistochemistry (74%) and NanoString analysis (88%). Unsupervised hierarchical clustering of an extended-NanoString/Lymph2Cx demonstrated significantly different GEP-clusters for PB-DLBCL as opposed to NO-DLBCL-GCB (P<0.001). Expression levels of 23 genes of two different targeted GEP-panels, indicated a centrocyte–like phenotype for PB-DLBCL, whereas NO-DLBCL-GCB showed a centroblast-like constitution. PB-DLBCL had significantly more frequent mutations in four GCB-associated genes, i.e. B2M, EZH2, IRF8, and TNFRSF14, compared to NO-DLBCL-GCB (P=0.031, P=0.010, P=0.047, and P=0.003). PB-DLBCL with its corresponding specific mutational profile were significantly associated with a superior overall survival compared to equivalent Ann Arbor limited-stage I/II NO-DLBCL-GCB (P=0.011). This study is the first to demonstrate that PB-DLBCL is characterized by a GCB-phenotype, with a centrocyte-like GEP-pattern and a GCB-associated mutational profile (both involved in immune surveillance) and a favorable prognosis. These novel biology-associated features provide evidence that PB-DLBCL represents a distinct extranodal DLBCL entity and its specific mutational landscape holds potential for targeted therapies (e.g. EZH2-inhibitors). The NanoString analsyis consisted out of 219 probes for Lymph2Cx classifier (COO), MYC-activity GEP score, CNV-associated GEP signature, consensus clustering, and immune-ratio signature. This custome probeset was used to differentiate GEPs between osseous and non-osseos DLBCL of the GCB-phenotype.
2021-06-04 | GSE176126 | GEO
Project description:Diffuse large B-cell lymphoma (DLBCL) represents a heterogeneous diagnostic category with distinct molecular subtypes that can be defined by gene expression profiling. However, even within these defined subtypes, heterogeneity prevails. To further elucidate the pathogenesis of these entities, we determined the expression of the tumor suppressor phosphatase and tensin homolog (PTEN) in 248 primary DLBCL patient samples. These analyses revealed that loss of PTEN was detectable in 55% of germinal center B-cell-like (GCB) DLBCLs, whereas this abnormality was found in only 14% of non-GCB DLBCL patient samples. In GCB DLBCL, the PTEN status was inversely correlated with activation of the oncogenic PI3K/ protein kinase B (AKT) pathway in both DLBCL cell lines and primary patient samples. Re-expression of PTEN induced cytotoxicity in PTEN-deficient GCB DLBCL cell line models by inhibiting PI3K/AKT signaling, indicating an addiction to this pathway in this subset of GCB DLBCLs. PI3K/AKT inhibition induced down-regulation of the transcription factor MYC. Re-expression of MYC rescued GCB DLBCL cells from PTEN-induced toxicity, identifying a regulatory mechanism of MYC expression in DLBCL. Finally, pharmacologic PI3K inhibition resulted in toxicity selectively in PTEN-deficient GCB DLBCL lines. Collectively, our results indicate that PTEN loss defines a PI3K/ AKT-dependent GCB DLBCL subtype that is addicted to PI3K and MYC signaling and suggest that pharmacologic inhibition of PI3K might represent a promising therapeutic approach in these lymphomas.
2013-07-09 | GSE45495 | GEO
Project description:Diffuse large B-cell lymphoma (DLBCL) comprises molecularly distinct subgroups such as activated B-cell-like (ABC) and germinal center B-cell-like (GCB) DLBCLs. We previously reported that CD5(+) and CD5(-)CD10(+) DLBCL constitute clinically relevant subgroups. To determine whether these 2 subgroups are related to ABC and GCB DLBCLs, we analyzed the genomic imbalance of 99 cases (36 CD5(+), 19 CD5(-)CD10(+), and 44 CD5(-)CD10(-)) using array-based comparative genomic hybridization (CGH). Forty-six of these cases (22 CD5(+), 9 CD5(-)CD10(+), 1 CD5 (-), and 14 CD5(-)CD10(-)) were subsequently subjected to gene-expression profiling, resulting in their division into 28 ABC (19 CD5(+) and 9 CD5(-)CD10(-)) and 18 GCB (3 CD5(+), 7 CD5(-)CD10(+), and 8 CD5(-)CD10(-)) types. A comparison of genome profiles of distinct subgroups of DLBCL demonstrated that (1) ABC DLBCL is characterized by gain of 3q, 18q, and 19q and loss of 6q and 9p21, and GCB DLBCL is characterized by gain of 1q, 2p, 7q, and 12q; (2) the genomic imbalances characteristic of the CD5(+) and CD5(-)CD10(+) groups were similar to those of the ABC and GCB types, respectively. These findings suggest that CD5(+) and CD5(-)CD10(+) subgroups are included, respectively, in the ABC and GCB types. Finally, when searching for genomic imbalances that affect patients' prognosis, we found that 9p21 loss (p16(INK4a) locus) marks the most aggressive type of DLBCL. Expression profiles in 46 patients with DLBCL and 8 for normal lymph node biopsy samples.
2009-07-10 | E-GEOD-16920 | biostudies-arrayexpress
Project description:CD5-positive (CD5+) diffuse large B-cell lymphoma (DLBCL) has a poor prognosis and high incidence of central nervous system (CNS) relapse, even in the rituximab era. To determine the gene expression profile of CD5+ DLBCL, total RNA from 90 patients with DLBCL, including 33 CD5+ DLBCL and 57 CD5-negative (CD5-) DLBCL patients, was examined using Agilent human oligo microarrays. These cases were separated into 78 activated B-cell-like (ABC) DLBCLs and 12 germinal center B-cell-like (GCB) DLBCLs. All cases of CD5+ DLBCL were classified as ABC DLBCLs. The classifier based on gene expression used in a supervised analysis correctly identified CD5 expression in the DLBCL and ABC DLBCL samples. The gene most relevant to CD5 expression was SH3BP5. The enriched GO categories in the CD5+ ABC DLBCL signature gene set were multicellular organismal signaling, transmission of nerve impulse, and synaptic transmission. This present study, which includes the largest reported number of patients with CD5+ DLBCL, confirmed that most CD5+ DLBCLs are ABC DLBCLs, suggesting that therapeutic strategies for ABC DLBCL may be effective for the treatment of CD5+ DLBCL. Our CD5+ ABC DLBCL signature gene set may provide insights into the cause of the high frequency of CNS relapse in CD5+ DLBCL.
2015-05-19 | GSE66770 | GEO