Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Genomic alterations and gene expression in primary diffuse large B cell lymphomas of immune privileged sites

ABSTRACT: Primary diffuse large B cell lymphomas of different immune-privileged sites (IP-DLBCL) share many clinical and biological features, such as a relatively poor prognosis, preferential dissemination to other immune-privileged sites and deletion of the HLA region, which suggests that IP-DLBCL represents a separate entity. To further investigate the nature of IP-DLBCL, we investigated site-specific genomic aberrations in 16 testicular, 9 central nervous system (CNS) and 15 nodal DLBCL using array-CGH. We also determined minimal common regions of gain and loss. Using robust algorithms, the array-CGH data were combined with gene expression data to explore pathways deregulated by chromosomal aberrations. Keywords: comparative genomic hybridisation, gene expression, tumor type comparison Whole tissue sections of 16 testicular, 9 central nervous system (CNS) and 15 nodal DLBCL were used for isolation of genomic DNA and total RNA. Genomic aberrations were determined using an in house printed CGH array containing ~3700 large genomic insert clones. Gene expression was analyzed on Affymetrix HU133 plus 2.0 oligo arrays. Gene expression data and arrayCGH data were combined using the R program ACE-it.

ORGANISM(S): Homo sapiens

SUBMITTER: Booman M

PROVIDER: S-ECPF-GEOD-10524 | biostudies-other | 2008 Oct

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Genomic alterations and gene expression in primary diffuse large B cell lymphomas of immune privileged sites

2008-06-19 | GSE10524 | GEO

Genomic alterations and gene expression in primary diffuse large B cell lymphomas of immune privileged sites

Project description:Primary diffuse large B cell lymphomas of different immune-privileged sites (IP-DLBCL) share many clinical and biological features, such as a relatively poor prognosis, preferential dissemination to other immune-privileged sites and deletion of the HLA region, which suggests that IP-DLBCL represents a separate entity. To further investigate the nature of IP-DLBCL, we investigated site-specific genomic aberrations in 16 testicular, 9 central nervous system (CNS) and 15 nodal DLBCL using array-CGH. We also determined minimal common regions of gain and loss. Using robust algorithms, the array-CGH data were combined with gene expression data to explore pathways deregulated by chromosomal aberrations. Keywords: comparative genomic hybridisation, gene expression, tumor type comparison Whole tissue sections of 16 testicular, 9 central nervous system (CNS) and 15 nodal DLBCL were used for isolation of genomic DNA and total RNA. Genomic aberrations were determined using an in house printed CGH array containing ~3700 large genomic insert clones. Gene expression was analyzed on Affymetrix HU133 plus 2.0 oligo arrays. Gene expression data and arrayCGH data were combined using the R program ACE-it.

2008-06-18 | E-GEOD-10524 | biostudies-arrayexpress

Differential micro-RNA expression in primary CNS and nodal diffuse large B-cell lymphomas.

Project description:Most primary CNS lymphomas (PCNSL) are diffuse large B-cell lymphomas (DLBCL). However, clinical behavior and prognosis differ considerably from those for nodal DLBCL (nDLBCL), and their pathogenesis is still not fully understood. Micro-RNAs (miRNAs) have been associated with cancer development and progression. We investigated a large miRNA panel for differential expression in PCNSL and nDLBCL, to determine new mechanisms potentially involved in PCNSL pathogenesis. Using paraffin-embedded biopsy specimens from 21 HIV-negative patients with newly diagnosed PCNSL (n = 11) and nDLBCL (n= 10), we measured the expression of 365 miRNA species by quantitative real-time PCR using low-density PCR arrays. We found that 18 miRNAs were differentially expressed: median expression levels of 13 miRNAs were 2.1-13.1 times higher in PCNSL, and median expression levels of 5 miRNAs were 2.6-3.3 times higher in nDLBCL. MiRNAs upregulated in PCNSL were associated with the Myc pathway (miR-17-5p, miR-20a, miR-9), with blocking of terminal B-cell differentiation (miR-9, miR-30b/c), or with upregulation by inflammatory cytokines (miR-155). Putative tumor-suppressor miRNAs (miR-199a, miR-214, miR-193b, miR-145) were downregulated in PCNSL. There was no overlap of miRNAs dysregulated in PCNSL with those differentially expressed between immunohistologically defined germinal center B cell-like (GCB) and non-GCB types or, apart from miR-9, with miRNAs known to be overexpressed in human brain. We conclude that PCNSL exhibits a distinct pattern of miRNA expression compared with nDLBCL. This argues for the involvement of different molecular mechanisms in the pathogenesis of these two lymphoma types.

| S-EPMC3177663 | biostudies-literature

Genomic profiles of diffuse large B-cell lymphomas

Project description:Despite recent therapeutic improvements, the clinical course of diffuse large B-cell lymphoma (DLBCL) still differs considerably among patients. We conducted this retrospective multi-centre study to evaluate the impact of genomic aberrations detected using a high-density genome wide-single nucleotide polymorphism-based array on clinical outcome in a population of DLBCL patients treated with R-CHOP-21 (rituximab, cyclophosphamide, doxorubicine, vincristine and prednisone repeated every 21 d). 167 DNA samples were analysed using the GeneChip Human Mapping 250K NspI. Genomic anomalies were analysed regarding their impact on the clinical course of 124 patients treated with R-CHOP-21. Unsupervised clustering was performed to identify genetically related subgroups of patients with different clinical outcomes. Twenty recurrent genetic lesions showed an impact on the clinical course. Loss of genomic material at 8p23.1 showed the strongest statistical significance and was associated with additional aberrations, such as 17p- and 15q-. Unsupervised clustering identified five DLBCL clusters with distinct genetic profiles, clinical characteristics and outcomes. Genetic features and clusters, associated with a different outcome in patients treated with R-CHOP, have been identified by arrayCGH. DNA copy number profiling by SNP array.

2009-04-01 | GSE15127 | GEO

High prevalence of oncogenic MYD88 and CD79B mutations in diffuse large B-cell lymphomas presenting at immune-privileged sites.

Project description:Activating mutations in CD79 and MYD88 have recently been found in a subset of diffuse large B-cell lymphoma (DLBCL), identifying B-cell receptor and MYD88 signalling as potential therapeutic targets for personalized treatment. Here, we report the prevalence of CD79B and MYD88 mutations and their relation to established clinical, phenotypic and molecular parameters in a large panel of DLBCLs. We show that these mutations often coexist and demonstrate that their presence is almost mutually exclusive with translocations of BCL2, BCL6 and cMYC, or Epstein-Bar virus infection. Intriguingly, MYD88 mutations were by far most prevalent in immune-privileged site-associated DLBCL (IP-DLBCL), presenting in central nervous system (75%) or testis (71%) and relatively uncommon in nodal (17%) and gastrointestinal tract lymphomas (11%). Our results suggest that MYD88 and CD79B mutations are important drivers of IP-DLBCLs and endow lymphoma-initiating cells with tissue-specific homing properties or a growth advantage in these barrier-protected tissues.

| S-EPMC3789201 | biostudies-literature

Genomic profiles of diffuse large B-cell lymphomas

Project description:Recurrent genomic aberrations have been obtained using a genome-wide DNA profiling. DNA copy number profiling by SNP array. 12 DLBCL samples. No technical replications.

2010-04-08 | E-GEOD-15127 | biostudies-arrayexpress

Genomic Analyses Identify Recurrent Alterations in Immune Evasion Genes in Diffuse Large B-Cell Lymphoma, Leg Type.

Project description:Cutaneous diffuse large B-cell lymphomas (DLBCLs) are aggressive lymphomas with a poor prognosis. To elucidate their genetic bases, we analyzed exome sequencing of 37 cutaneous DLBCLs, including 31 DLBCLs, leg type (DLBCL-LT) and 6 cutaneous DLBCLs-not otherwise specified (DLBCL-NOS). As reported previously, 77% of DLBCL-LT harbor NF-?B-activating MYD88 mutations. In nearly all MYD88-wild-type DLBCL-LT, we found cancer-promoting mutations that either activate the NF-?B pathway through alternative genes (NFKBIE or REL) or activate other canonical cancer pathways (BRAF, MED12, PIK3R1, and STAT3). After NF-?B, the second most commonly mutated pathway putatively enables immune evasion via mutations predicted to downregulate antigen processing (B2M, CIITA, HLA) or T-cell co-stimulation (CD58). DLBCL-LT have little genetic overlap with the genetically heterogeneous DLBCL-NOS. Instead, they resemble primary central nervous system and testicular large B-cell lymphomas (primary central nervous system lymphomas and primary testicular lymphomas). Like primary central nervous system lymphomas/primary testicular lymphomas, 40% of DLBCL-LT (vs. 0% of DLBCLs-not otherwise specified) harbored PDL1/PDL2 translocations, which lead to overexpression of PD-L1 or PD-L2 in 50% of the cases. Collectively, these data broaden our understanding of cutaneous DLBCLs and suggest novel therapeutic approaches (e.g., BRAF or PI3K inhibitors). Additionally, they suggest novel treatment paradigms, wherein DLBCL-LT can be targeted with strategies (e.g., immune checkpoint blockers) currently being developed for genomically similar primary central nervous system lymphomas/primary testicular lymphomas.

| S-EPMC6200585 | biostudies-literature

Diffuse large B cell lymphomas

Project description:Intrinsic resistance of lymphoma cells to apoptosis is a probable mechanism causing chemotherapy resistance and eventual fatal outcome in patients with diffuse large B cell lymphomas (DLBCL). We investigated whether microarray expression profiling of apoptosis related genes predicts clinical outcome in 46 patients with primary nodal DLBCL. Unsupervised cluster analysis using genes involved in apoptosis (N=246) resulted in 3 separate DLBCL groups partly overlapping with GCB versus ABC like phenotype. One group with poor clinical outcome was characterized by high expression levels of pro-and anti-apoptotic genes involved in the intrinsic apoptosis pathway. A 2nd group, also with poor clinical outcome, was characterized by high levels of apoptosis inducing cytotoxic effector genes, possibly reflecting a cellular cytotoxic immune response. The 3rd group showing a favourable outcome was characterized by low expression levels of genes characteristic for both other groups. Our results suggest that chemotherapy refractory DLBCL are characterized either by an intense cellular cytotoxic immune response or by constitutive activation of the intrinsic mediated apoptosis pathway with concomitant downstream inhibition of this apoptosis pathway. Consequently, strategies neutralizing the function of apoptosis-inhibiting proteins might be effective as alternative treatment modality in part of chemotherapy refractory DLBCL. Keywords: expression profiling B lymphomas

2006-12-08 | GSE3892 | GEO

Lenalidomide in diffuse large B-cell lymphomas.

Project description:Diffuse Large B-cell Lymphomas (DLBCL) are the most frequent Non-Hodgkin Lymphomas (NHL). The addition of Rituximab to the standard chemotherapy CHOP improved the outcome in this patients, but so far 40% of patients experienced relapse or progressive disease. Lenalidomide, an immunomodulatory agent, had direct tumoricidal and antiangiogenetic actions on tumor cells and was able to modulate tumor-cell microenvironment, with the restoration of impaired T-cell activity and the formation of immuno-synapsis. Based on these actions, lenalidomide represented an active drug on aggressive relapsed NHL. In this review, the most relevant clinical trials for the use of lenalidomide in DLBCL were reported. Monotherapy with lenalidomide showed an activity in term of overall response rate, with acceptable hematological and extrahematological toxicities in relapsed/refractory aggressive NHL. The role of lenalidomide as salvage therapy in both cell of origin patterns in DLBCL (germinal center B-cell/activated B-cell) was reported in preliminary data. Preliminary data regarding the role of lenalidomide in addition to chemoimmunotherapy (R-CHOP) in first line clinical trials were discussed; data of safety, feasibility and efficacy were promising.

| S-EPMC3390034 | biostudies-literature

Genomic Variation in Diffuse Large B Cell Lymphomas

Project description:Genomic Variation in Diffuse Large B Cell Lymphomas

| PRJNA400524 | ENA