scholarly journals Enhancing B-Cell Malignancies—On Repurposing Enhancer Activity towards Cancer

Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3270
Author(s):  
Marta Elżbieta Kasprzyk ◽  
Weronika Sura ◽  
Agnieszka Dzikiewicz-Krawczyk
Keyword(s):  
B Cells ◽  
B Cell ◽  
Regulatory Sequences ◽  
Cell Type ◽  
Enhancer Activity ◽  
Common Cancer ◽  
Specific Manner ◽  
Dna Elements ◽  
A Cell

B-cell lymphomas and leukemias derive from B cells at various stages of maturation and are the 6th most common cancer-related cause of death. While the role of several oncogenes and tumor suppressors in the pathogenesis of B-cell neoplasms was established, recent research indicated the involvement of non-coding, regulatory sequences. Enhancers are DNA elements controlling gene expression in a cell type- and developmental stage-specific manner. They ensure proper differentiation and maturation of B cells, resulting in production of high affinity antibodies. However, the activity of enhancers can be redirected, setting B cells on the path towards cancer. In this review we discuss different mechanisms through which enhancers are exploited in malignant B cells, from the well-studied translocations juxtaposing oncogenes to immunoglobulin loci, through enhancer dysregulation by sequence variants and mutations, to enhancer hijacking by viruses. We also highlight the potential of therapeutic targeting of enhancers as a direction for future investigation.

scholarly journals miR-27 and miR-125 Distinctly Regulate Muscle-Enriched Transcription Factors in Cardiac and Skeletal Myocytes

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Estefania Lozano-Velasco ◽  
Jennifer Galiano-Torres ◽  
Alvaro Jodar-Garcia ◽  
Amelia E. Aranega ◽  
Diego Franco
Keyword(s):  
Transcription Factors ◽  
Cardiac Development ◽  
Protein Translation ◽  
Cell Type ◽  
Atrial Cardiomyocytes ◽  
Skeletal Myocytes ◽  
Specific Manner ◽  
A Cell ◽  
Cell Type Specific

MicroRNAs are noncoding RNAs of approximately 22–24 nucleotides which are capable of interacting with the 3′ untranslated region of coding RNAs (mRNAs), leading to mRNA degradation and/or protein translation blockage. In recent years, differential microRNA expression in distinct cardiac development and disease contexts has been widely reported, yet the role of individual microRNAs in these settings remains largely unknown. We provide herein evidence of the role of miR-27 and miR-125 regulating distinct muscle-enriched transcription factors. Overexpression of miR-27 leads to impair expression ofMstnandMyocdin HL1 atrial cardiomyocytes but not in Sol8 skeletal muscle myoblasts, while overexpression of miR-125 resulted in selective upregulation ofMef2din HL1 atrial cardiomyocytes and downregulation in Sol8 cells. Taken together our data demonstrate that a single microRNA, that is, miR-27 or miR-125, can selectively upregulate and downregulate discrete number of target mRNAs in a cell-type specific manner.

scholarly journals Bcl-x rather than Bcl-2 mediates CD40-dependent centrocyte survival in the germinal center

Blood ◽  
1996 ◽  
Vol 88 (4) ◽  
pp. 1359-1364 ◽  
Author(s):  
JM Tuscano ◽  
KM Druey ◽  
A Riva ◽  
J Pena ◽  
CB Thompson ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Germinal Center ◽  
Protein Levels ◽  
Staphylococcus Aureus Cowan ◽  
A Cell ◽  
Tonsil Tissue ◽  
Cell Fractions ◽  
Selection Of

Both rapid B-cell proliferation and programmed cell death (PCD) occur during the differentiation and selection of B cells within the germinal center. To help elucidate the role of Bcl-x in B-cell antigen selection and PCD within the germinal center, we examined its expression in defined B-cell populations and by immunochemistry of tonsil tissue. Purified B-cell fractions enriched for centrocytes express high amounts of Bcl-x and relatively low amounts of Bcl-2, whereas fractions enriched for centroblasts lack significant levels of both proteins. Consistent with this observation, immunocytochemistry localized Bcl-x within cells scattered throughout the germinal center. Stimulation of tonsil B cells with either CD40 or Staphylococcus aureus Cowan increase bcl-x mRNA and protein levels. Treatment of a cell line with a germinal center phenotype (RAMOS) or the tonsillar B-cell centroblast fraction with CD40 rapidly increased Bcl-x levels and partially rescued B cells from PCD. These data suggest that Bcl-x rather than Bcl-2 may rescue centrocytes during selection in the germinal center.

scholarly journals Regulation of B Lymphocyte Development by Histone H2A Deubiquitinase BAP1

2021 ◽  
Vol 12 ◽  
Author(s):  
Yun Hsiao Lin ◽  
Yue Liang ◽  
HanChen Wang ◽  
Lin Tze Tung ◽  
Michael Förster ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Cell Cycle Progression ◽  
B Lymphocyte ◽  
Cell Development ◽  
B Cell Development ◽  
Lymphocyte Development ◽  
A Cell ◽  
B Lymphocyte Development

BAP1 is a deubiquitinase (DUB) of the Ubiquitin C-terminal Hydrolase (UCH) family that regulates gene expression and other cellular processes, via deubiquitination of histone H2AK119ub and other substrates. BAP1 is an important tumor suppressor in human, expressed and functional across many cell-types and tissues, including those of the immune system. B lymphocytes are the mediators of humoral immune response, however the role of BAP1 in B cell development and physiology remains poorly understood. Here we characterize a mouse line with a selective deletion of BAP1 within the B cell lineage (Bap1fl/fl mb1-Cre) and establish a cell intrinsic role of BAP1 in the regulation of B cell development. We demonstrate a depletion of large pre-B cells, transitional B cells, and mature B cells in Bap1fl/fl mb1-Cre mice. We characterize broad transcriptional changes in BAP1-deficient pre-B cells, map BAP1 binding across the genome, and analyze the effects of BAP1-loss on histone H2AK119ub levels and distribution. Overall, our work establishes a cell intrinsic role of BAP1 in B lymphocyte development, and suggests its contribution to the regulation of the transcriptional programs of cell cycle progression, via the deubiquitination of histone H2AK119ub.

scholarly journals N-cadherin (Cdh2) Maintains Migration and Postmitotic Survival of Cortical Interneuron Precursors in a Cell-Type-Specific Manner

2019 ◽  
Vol 30 (3) ◽  
pp. 1318-1329
Author(s):  
Zsófia I László ◽  
Kinga Bercsényi ◽  
Mátyás Mayer ◽  
Kornél Lefkovics ◽  
Gábor Szabó ◽  
...  
Keyword(s):  
Target Selection ◽  
Cortical Plate ◽  
Specific Factor ◽  
Cell Type ◽  
Cortical Interneuron ◽  
Specific Manner ◽  
A Cell ◽  
Cell Type Specific ◽  
Interneuron Development

Abstract The multiplex role of cadherin-based adhesion complexes during development of pallial excitatory neurons has been thoroughly characterized. In contrast, much less is known about their function during interneuron development. Here, we report that conditional removal of N-cadherin (Cdh2) from postmitotic neuroblasts of the subpallium results in a decreased number of Gad65-GFP-positive interneurons in the adult cortex. We also found that interneuron precursor migration into the pallium was already delayed at E14. Using immunohistochemistry and TUNEL assay in the embryonic subpallium, we excluded decreased mitosis and elevated cell death as possible sources of this defect. Moreover, by analyzing the interneuron composition of the adult somatosensory cortex, we uncovered an unexpected interneuron-type-specific defect caused by Cdh2-loss. This was not due to a fate-switch between interneuron populations or altered target selection during migration. Instead, potentially due to the migration delay, part of the precursors failed to enter the cortical plate and consequently got eliminated at early postnatal stages. In summary, our results indicate that Cdh2-mediated interactions are necessary for migration and survival during the postmitotic phase of interneuron development. Furthermore, we also propose that unlike in pallial glutamatergic cells, Cdh2 is not universal, rather a cell type-specific factor during this process.

scholarly journals Chromatin accessibility determines intron retention in a cell type-specific manner

2021 ◽  
Author(s):  
Veronika Petrova ◽  
Renhua Song ◽  
Karl J.V. Nordström ◽  
Jörn Walter ◽  
Justin J.-L. Wong ◽  
...  
Keyword(s):  
Nucleosome Occupancy ◽  
Intron Retention ◽  
Chromatin Accessibility ◽  
Lymphoid Cells ◽  
Cell Type ◽  
Systematic Analysis ◽  
Specific Manner ◽  
A Cell ◽  
Cell Type Specific

SummaryDynamic intron retention (IR) in vertebrate cells is of widespread biological importance. Aberrant IR is associated with numerous human diseases including cancer. Despite consistent reports demonstrating intrinsic sequence features that predispose introns to become retained, conflicting findings about cell type-specific IR regulation demand a systematic analysis in a controlled experimental setting. We integrated matched transcriptomics and epigenetics data (including DNA methylation, nucleosome occupancy, histone modifications) from primary human myeloid and lymphoid cells. Using machine learning we trained two complementary models to determine the role of epigenetic factors in the regulation of IR. We show that increased chromatin accessibility contributes substantially to the retention of introns in a cell-specific manner. We also confirm that intrinsic characteristics of introns are key for them to evade splicing. With mounting reports linking pathogenic alterations to RNA processing, our findings may have profound implications for the design of therapeutic approaches targeting aberrant splicing.

Lymphoproliferative disorders (LPD) involving lungs: T and B cell subsets within pulmonary infiltrates and in peripheral blood

1984 ◽  
Vol 42 ◽  
pp. 700-701
Author(s):  
Irene Stachura ◽  
Milton H. Dalbow ◽  
Michael J. Niemiec ◽  
Matias Pardo ◽  
Gurmukh Singh ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Lymphoproliferative Disorders ◽  
Mixed Population ◽  
Lymphoid Cells ◽  
Lymphomatoid Granulomatosis ◽  
Cell Type ◽  
Cell Surface Antigens ◽  
Pulmonary Infiltrates ◽  
B Cell Subsets

Lymphoid cells were analyzed within pulmonary infiltrates of six patients with lymphoproliferative disorders involving lungs by immunofluorescence and immunoperoxidase techniques utilizing monoclonal antibodies to cell surface antigens T11 (total T), T4 (inducer/helper T), T8 (cytotoxic/suppressor T) and B1 (B cells) and the antisera against heavy (G,A,M) and light (kappa, lambda) immunoglobulin chains. Three patients had pseudolymphoma, two patients had lymphoma and one patient had lymphomatoid granulomatosis.A mixed population of cells was present in tissue infiltrates from the three patients with pseudolymphoma, IgM-kappa producing cells constituted the main B cell type in one patient. In two patients with lymphoma pattern the infiltrates were composed exclusively of T4+ cells and IgG-lambda B cells predominated slightly in the patient with lymphomatoid granulomatosis.

Bruton's tyrosine kinase inhibition in the treatment of preclinical models and multiple sclerosis

2021 ◽  
Vol 27 ◽  
Author(s):  
Anja Steinmaurer ◽  
Isabella Wimmer ◽  
Thomas Berger ◽  
Paulus Stefan Rommer ◽  
Johann Sellner
Keyword(s):  
Multiple Sclerosis ◽  
B Cells ◽  
Tyrosine Kinase ◽  
B Cell ◽  
Bruton’S Tyrosine Kinase ◽  
Cumulative Number ◽  
Phase 2 ◽  
Bruton's Tyrosine Kinase ◽  
Relapsing Remitting

: Significant progress has been made in understanding the immunopathogenesis of multiple sclerosis (MS) over recent years. Successful clinical trials with CD20-depleting monoclonal antibodies have corroborated the fundamental role of B cells in the pathogenesis of MS and reinforced the notion that cells of the B cell lineage are an attractive treatment target. Therapeutic inhibition of Bruton's tyrosine kinase (BTK), an enzyme involved in B cell and myeloid cell activation and function, is regarded as a next-generation approach that aims to attenuate both errant innate and adaptive immune functions. Moreover, brain-penetrant BTK inhibitors may impact compartmentalized inflammation and neurodegeneration within the central nervous system by targeting brain-resident B cells and microglia, respectively. Preclinical studies in animal models of MS corroborated an impact of BTK inhibition on meningeal inflammation and cortical demyelination. Notably, BTK inhibition attenuated the antigen-presenting capacity of B cells and the generation of encephalitogenic T cells. Evobrutinib, a selective oral BTK inhibitor, has been tested recently in a phase 2 study of patients with relapsing-remitting MS. The study met the primary endpoint of a significantly reduced cumulative number of Gadolinium-enhancing lesions under treatment with evobrutinib compared to placebo treatment. Thus, the results of ongoing phase 2 and 3 studies with evobrutinib, fenobrutinib, and tolebrutinib in relapsing-remitting and progressive MS are eagerly awaited. This review article introduces the physiological role of BTK, summarizes the pre-clinical and trial evidence, and addresses the potential beneficial effects of BTK inhibition in MS.

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