Diffuse large B-cell lymphoma (DLBCL) is a clinically and molecularly heterogeneous disease. The increasing recognition and targeting of genetically defined DLBCLs highlights the need for robust classification algorithms. We previously characterized recurrent genetic alterations in DLBCL and identified five discrete subtypes, Clusters 1-5 (C1-C5), with unique mechanisms of transformation, immune evasion, candidate treatment targets and different outcomes following standard first-line therapy.
View Article and Find Full Text PDFLigation of the B cell antigen receptor (BCR) initiates humoral immunity. However, BCR signaling without appropriate co-stimulation commits B cells to death rather than to differentiation into immune effector cells. How BCR activation depletes potentially autoreactive B cells while simultaneously primes for receiving rescue and differentiation signals from cognate T lymphocytes remains unknown.
View Article and Find Full Text PDFThe diagnosis and treatment of malignant lymphoma is rapidly advancing, offering hope but also highlighting inherent limitations. Technological breakthroughs in sequencing technologies enable more precise subtyping and risk stratification. For example, in diffuse large B-cell lymphoma (DLBCL), exome sequencing revealed molecular subtypes.
View Article and Find Full Text PDFChimeric antigen receptor T cell (CAR T) therapy is a potent treatment for relapsed/refractory (r/r) B cell lymphomas but provides lasting remissions in only ∼40% of patients and is associated with serious adverse events. We identify an upregulation of CD80 and/or CD86 in tumor tissue of (r/r) diffuse large B cell lymphoma (DLBCL) patients treated with tisagenlecleucel. This finding leads to the development of the CAR/CCR (chimeric checkpoint receptor) design, which consists of a CD19-specific first-generation CAR co-expressed with a recombinant CTLA-4-linked receptor with a 4-1BB co-stimulatory domain.
View Article and Find Full Text PDFThe structure and dynamics of F-actin networks in the cortical area of B cells control the signal efficiency of B-cell antigen receptors (BCRs). Although antigen-induced signaling has been studied extensively, the role of cortical F-actin in antigen-independent tonic BCR signaling is less well understood. Because these signals are essential for the survival of B cells and are consequently exploited by several B-cell lymphomas, we assessed how the cortical F-actin structure influences tonic BCR signal transduction.
View Article and Find Full Text PDFBackground: Secondary central nervous system lymphoma (SCNSL) confers a dismal prognosis and treatment advances are constrained by the lack of prospective studies and real-world treatment evidence.
Methods: Patients with SCNSL of all entities were included at first diagnosis and patient characteristics, treatment data, and outcomes were prospectively collected in the Secondary CNS Lymphoma Registry (SCNSL-R) (NCT05114330).
Findings: 279 patients from 47 institutions were enrolled from 2011 to 2022 and 243 patients (median age: 66 years; range: 23-86) were available for analysis.
Burkitt lymphoma cells (BL) exploit antigen-independent tonic signals transduced by the B-cell antigen receptor (BCR) for their survival, but the molecular details of the rewired BL-specific BCR signal network remain unclear. A loss of function screen revealed the SH2 domain-containing 5`-inositol phosphatase 2 (SHIP2) as a potential modulator of BL fitness. We characterized the role of SHIP2 in BL survival in several BL cell models and show that perturbing SHIP2 function renders cells more susceptible to apoptosis, while attenuating proliferation in a BCR-dependent manner.
View Article and Find Full Text PDFSecondary central nervous system lymphoma (SCNSL) is a rare and difficult to treat type of Non-Hodgkin lymphoma characterized by systemic and central nervous system (CNS) disease manifestations. In this study, 124 patients with SCNSL intensively treated and with clinical long-term follow-up were included. Initial histopathology, as divided in low-grade, other aggressive, and diffuse large B-cell lymphoma (DLBCL), was of prognostic significance.
View Article and Find Full Text PDFDiffuse large B-cell lymphoma (DLBCL) is a clinically and genetically heterogeneous disease with at least 5 recognized molecular subtypes. Cluster 5 (C5)/MCD tumors frequently exhibit concurrent alterations in the toll-like receptor (TLR) and B-cell receptor (BCR) pathway members, MYD88L265P and CD79B, and have a less favorable prognosis. In healthy B cells, the synergy between TLR and BCR signaling pathways integrates innate and adaptive immune responses and augments downstream NF-κB activation.
View Article and Find Full Text PDFUnlabelled: Genomic profiling revealed the identity of at least 5 subtypes of diffuse large B-cell lymphoma (DLBCL), including the MCD/C5 cluster characterized by aberrations in MYD88, BCL2, PRDM1, and/or SPIB. We generated mouse models harboring B cell-specific Prdm1 or Spib aberrations on the background of oncogenic Myd88 and Bcl2 lesions. We deployed whole-exome sequencing, transcriptome, flow-cytometry, and mass cytometry analyses to demonstrate that Prdm1- or Spib-altered lymphomas display molecular features consistent with prememory B cells and light-zone B cells, whereas lymphomas lacking these alterations were enriched for late light-zone and plasmablast-associated gene sets.
View Article and Find Full Text PDFActivated SUMOylation is a hallmark of cancer. Starting from a targeted screening for SUMO-regulated immune evasion mechanisms, we identified an evolutionarily conserved function of activated SUMOylation, which attenuated the immunogenicity of tumor cells. Activated SUMOylation allowed cancer cells to evade CD8+ T cell-mediated immunosurveillance by suppressing the MHC class I (MHC-I) antigen-processing and presentation machinery (APM).
View Article and Find Full Text PDFGenetic alterations in the DNA damage response (DDR) pathway are a frequent mechanism of resistance to chemoimmunotherapy (CIT) in B-cell malignancies. We have previously shown that the synergy of CIT relies on secretory crosstalk elicited by chemotherapy between the tumor cells and macrophages. Here, we show that loss of multiple different members of the DDR pathway inhibits macrophage phagocytic capacity in vitro and in vivo.
View Article and Find Full Text PDFAcute myeloid leukemia (AML) is an aggressive blood cancer with a poor prognosis. We report a comprehensive proteogenomic analysis of bone marrow biopsies from 252 uniformly treated AML patients to elucidate the molecular pathophysiology of AML in order to inform future diagnostic and therapeutic approaches. In addition to in-depth quantitative proteomics, our analysis includes cytogenetic profiling and DNA/RNA sequencing.
View Article and Find Full Text PDFLarge-scale genomic profiling of pancreatic cancer (PDAC) has revealed two distinct subtypes: 'classical' and 'basal-like'. Their variable coexistence within the stromal immune microenvironment is linked to differential prognosis; however, the extent to which these neoplastic subtypes shape the stromal immune landscape and impact clinical outcome remains unclear. By combining preclinical models, patient-derived xenografts, as well as FACS-sorted PDAC patient biopsies, we show that the basal-like neoplastic state is sustained via BRD4-mediated cJUN/AP1 expression, which induces CCL2 to recruit tumor necrosis factor (TNF)-α-secreting macrophages.
View Article and Find Full Text PDFSUMOylation is a post-translational modification of proteins that regulates these proteins' localization, turnover or function. Aberrant SUMOylation is frequently found in cancers but its origin remains elusive. Using a genome-wide transposon mutagenesis screen in a MYC-driven B-cell lymphoma model, we here identify the SUMO isopeptidase (or deconjugase) SENP6 as a tumor suppressor that links unrestricted SUMOylation to tumor development and progression.
View Article and Find Full Text PDFPersonalized medicine aims to tailor treatment to patients based on their individual genetic or molecular background. Especially in diseases with a large molecular heterogeneity, such as diffuse large B-cell lymphoma (DLBCL), personalized medicine has the potential to improve outcome and/or to reduce resistance towards treatment. However, integration of patient-specific information into a computational model is challenging and has not been achieved for DLBCL.
View Article and Find Full Text PDFThe family of PIM serine/threonine kinases includes three highly conserved oncogenes, and , which regulate multiple prosurvival pathways and cooperate with other oncogenes such as . Recent genomic CRISPR-Cas9 screens further highlighted oncogenic functions of PIMs in diffuse large B-cell lymphoma (DLBCL) cells, justifying the development of small-molecule PIM inhibitors and therapeutic targeting of PIM kinases in lymphomas. However, detailed consequences of PIM inhibition in DLBCL remain undefined.
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