Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Lamin B1 regulates somatic mutations and progression of B cell malignancies

ABSTRACT: Somatic hypermutation (SHM) is a pivotal process in adaptive immunity that occurs in the germinal centre and allows B-cells to change their primary DNA sequence and diversify their antigen receptors. Here, we report that genome binding of Lamin B1, a component of the nuclear envelope involved in epigenetic chromatin regulation, is reduced during B cell activation and formation of lymphoid germinal centres. ChIP-Seq analysis showed that kappa and heavy variable immunoglobulin domains were released from the Lamin B1 suppressive environment when SHM was induced in B cells. RNAi-mediated reduction of Lamin B1 resulted in spontaneous SHM as well as kappa-light chain aberrant surface expression. Finally, Lamin B1 expression level was directly proportional to 5-year survival rate in chronic lymphocytic leukaemia, and was strongly involved in transformation of follicular lymphoma. In summary, here we report that Lamin B1 is a negative epigenetic regulator of SHM in normal B-cells and a "mutational gatekeeper", suppressing the aberrant mutations that drive lymphoid malignancy.

ORGANISM(S): Homo sapiens

PROVIDER: GSE89869 | GEO | 2017/08/03

SECONDARY ACCESSION(S): PRJNA353616

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Expression data from functional studies using RNAi on Lamin B1 in BL2 cells

Project description:Lamin B1 is a component of the nuclear envelope involved in epigenetic chromatin regulation and is reduced during B cell activation and formation of lymphoid germinal centres. RNAi-mediated reduction of Lamin B1 results in spontaneous SHM as well as kappa-light chain aberrant surface expression showing that Lamin B1 is a negative epigenetic regulator of SHM. We used Affymetrix Exon 1.0 ST microarrays to detail the global programme of gene expression underlying changes induced in siRNA-treated Lamin B1low BL2 cells. siRNA-mediated reduction of nuclear Lamin B1 incorporation resulted in a general upregulation of positive cell cycle regulatory genes which in turn occurred alongside an upregulation of genes responsible for cell cycle checkpoint execution or cell cycle arrest, and were specific for LMNB1 reduction.

2017-08-16 | GSE98529 | GEO

Lamin B1 loss promotes lung cancer development and metastasis by epigenetic derepression of RET [ChIP-Seq]

Project description:Although abnormal nuclear structure is an important criterion for cancer diagnostics, remarkably little is known about its relationship to tumor development. Here we report that loss of lamin B1, a determinant of nuclear architecture, plays a key role in lung cancer. We found that lamin B1 levels were reduced in lung cancer patients. Lamin B1 silencing in lung epithelial cells promoted epithelial-mesenchymal transition, cell migration, tumor growth and metastasis. Mechanistically, we show that lamin B1 recruits the polycomb repressive complex 2 (PRC2) to alter the H3K27me3 landscape and repress genes involved in cell migration and signaling. In particular, epigenetic derepression of the RET proto-oncogene by loss of PRC2 recruitment, and activation of the RET/p38 signaling axis, play a crucial role in mediating the malignant phenotype upon lamin B1 disruption. Importantly, loss of a single lamin B1 allele induced spontaneous lung tumor formation and RET activation. Thus, lamin B1 acts as a tumor suppressor in lung cancer, linking aberrant nuclear structure and epigenetic patterning with malignancy.

2019-04-15 | GSE94679 | GEO

Lamin B1 loss promotes lung cancer development and metastasis by epigenetic derepression of RET [RNA-Seq]

2019-04-15 | GSE94680 | GEO

Independent roles of switching and hypermutation in the development and persistence of B lymphocyte memory [Nurr77]

Project description:Somatic hypermutation (SHM) and class switch recombination (CSR) increase the affinity and diversify the effector functions of antibodies during immune responses. Although SHM and CSR are fundamentally different, their independent roles in regulating B cell fate have been difficult to uncouple because a single enzyme, activation-induced cytidine deaminase (encoded by Aicda), initiates both reactions. Here, we used a combination of Aicda and antibody mutant alleles that separate the effects of CSR and SHM on polyclonal immune responses. We found that class-switching to IgG1 biased the fate choice made by B cells, favoring the plasma cell over memory cell fate without significantly affecting clonal expansion in the germinal center (GC). In contrast, SHM reduced the longevity of memory B cells by creating polyreactive specificities that were selected against over time. Our data define the independent contributions of SHM and CSR to the generation and persistence of memory in the antibody system.

2016-10-19 | GSE76865 | GEO

Independent roles of switching and hypermutation in the development and persistence of B lymphocyte memory [IgM_IgG1]

2016-10-19 | GSE76864 | GEO

Lamin B1 ChIPseq experiments from ER:RAS IMR90s

Project description:Lamin B1 from OIS IMR90s We used ChIP-seq to examine the global binding of Lamin B1 in human IMR90 oncogene-induced senescence

2014-12-15 | E-GEOD-53331 | biostudies-arrayexpress

Lamin B1 dependent transcriptional control in neural progenitor cells

Project description:Through knocking out Lamin B1, we found that lamin B1 regulets hundreds of genes in neural progenitor cells, which underlie differentiation of neural protenitor cells

2021-02-10 | GSE156156 | GEO

Gene expression analysis of B-NHL from λMYC, λMYC/IµHABCL6, λMYC/AIDKO and λMYC/IµHABCL6/AIDKO mouse models

Project description:Most human B cell lymphomas (B-NHL) are derived from germinal centers (GCs), the structure where B-cells undergo class switch recombination (CSR) and somatic hypermutation (SHM) and are selected for high-affinity antibody production. The pathogenesis of B-NHL is associated with distinct genetic lesions, including chromosomal translocations and aberrant somatic hypermutation, which appear to arise from mistakes occurring during CSR and SHM. To ascertain the role of CSR and SHM in lymphomagenesis, we crossed three oncogene-driven (MYC, BCL6, MYC/BCL6) mouse models of B cell lymphoma with mice lacking activation-induced cytidine deaminase (AID), the enzyme required for both processes. We show that AID deficiency prevents BCL6-dependent, GC-derived B-NHL, while it has no impact on the formation of MYC-driven, pre-GC lymphomas. Accordingly, abrogation of AID is associated with the disappearance of both CSR- and SHM-mediated structural alterations, including cMYC-IgH chromosomal translocations and aberrant SHM. These results demonstrate that AID is required for GC-derived lymphomagenesis, providing direct support to the notion that errors in AID-mediated antigen-receptor gene modification events represent major contributors to the pathogenesis of human B-NHL. Keywords: Phenotypic characterization of tumors developing in oncogene-driven mouse models of lymphomas

2007-11-01 | GSE9249 | GEO

Autophagy mediates degradation of nuclear lamina

Project description:Autophagy is a catabolic membrane trafficking process involved in degradation of cellular constituents through lysosomes, which maintains cell and tissue homeostasis. While much attention has been focused on autophagic turnover of cytoplasmic materials, little is known regarding the role of autophagy in degrading nuclear components. Here we report that autophagy machinery mediates degradation of nuclear lamina in mammalian cells, a process we term laminophagy. The autophagy protein LC3 is present in the nucleus and directly interacts with the nuclear lamina protein Lamin B1, and associates with lamin-associated domains (LADs) on chromatin. This interaction does not downregulate Lamin B1 during starvation, but mediates nuclear lamina degradation upon tumorigenic insults, such as by oncogenic Ras. Laminophagy is achieved by nucleus-to-cytosol transport that delivers Lamin B1 to lysosome for degradation. Inhibiting autophagy or LC3-Lamin B1 interaction prevents oncogenic Ras-induced Lamin B1 loss and delays oncogene-induced cell cycle arrest. Our study unveils a role of autophagy in degrading nuclear materials, and suggests laminophagy as a guarding mechanism protecting cells from tumorigenesis.

2015-10-08 | GSE63440 | GEO

Distinct B-Cell Specific Transcriptional Contexts of the BCL2 Oncogene Impact Pre-Malignant Development in Mouse Models [RNA-Seq]

Project description:We designed two different BCL2 deregulation models in transgenic mice, whereby the oncogene was either associated with the IgH3′RR superenhancer, as in t(14;18), or inserted into the kappa light chain locus. We compared the impact of these models on B-cell fate and lymphoid tissues. Linkage to the IgH superenhancer showed a quite specific impact on germinal center B cell populations. The Ig kappa model was much less specific and strongly boosted the plasma cell in-flow and the accumulation of long-lived plasma cells.

2022-11-10 | GSE217605 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data