A large body of evidence suggests that hypoxia drives aggressive molecular features of malignant cells irrespective of cancer type. Non-Hodgkin lymphomas (NHL) are the most common hematologic malignancies characterized by frequent involvement of diverse hypoxic microenvironments. We studied the impact of long-term deep hypoxia (1% O2) on the biology of lymphoma cells. Only 2 out of 6 tested cell lines (Ramos, and HBL2) survived ≥ 4 weeks under hypoxia. The hypoxia-adapted (HA)b Ramos and HBL2 cells had a decreased proliferation rate accompanied by significant suppression of both oxidative phosphorylation and glycolytic pathways. Transcriptome and proteome analyses revealed marked downregulation of genes and proteins of the mitochondrial respiration complexes I and IV, and mitochondrial ribosomal proteins. Despite the observed suppression of glycolysis, the proteome analysis of both HA cell lines showed upregulation of several proteins involved in the regulation of glucose utilization including the active catalytic component of prolyl-4-hydroxylase P4HA1, an important druggable oncogene. HA cell lines demonstrated increased transcription of key regulators of auto-/mitophagy, e.g., neuritin, BCL2 interacting protein 3 (BNIP3), BNIP3-like protein, and BNIP3 pseudogene. Adaptation to hypoxia was further associated with deregulation of apoptosis, namely upregulation of BCL2L1/BCL-XL, overexpression of BCL2L11/BIM, increased binding of BIM to BCL-XL, and significantly increased sensitivity of both HA cell lines to A1155463, a BCL-XL inhibitor. Finally, in both HA cell lines AKT kinase was hyperphosphorylated and the cells showed increased sensitivity to copanlisib, a pan-PI3K inhibitor. In conclusion, our data report on several shared mechanisms of lymphoma cell adaptation to long-term hypoxia including: 1. Upregulation of proteins responsible for glucose utilization, 2. Degradation of mitochondrial proteins for potential mitochondrial recycling (by mitophagy), and 3. Increased dependence on BCL-XL and PI3K-AKT signaling for survival. In translation, inhibition of glycolysis, BCL-XL, or PI3K-AKT cascade may result in targeted elimination of HA lymphoma cells.

• Publikační typ
• časopisecké články MeSH

High-grade B-cell lymphomas (HGBCLs) are aggressive blood cancers with a severe disease course, especially when the central nervous system (CNS) is involved. Standard histological examination depends on tissue availability and is currently supplemented with molecular tests, as the status of MYC, BCL2, or BCL6 gene rearrangements is required for proper lymphoma classification. This case report demonstrates the relevance of cerebrospinal fluid (CSF) cell-free DNA testing by integrative next-generation sequencing (NGS) panel. The benefit of this approach resided in tumor genotyping alongside the proof of CNS progression despite MRI negativity, revealing a clonal relationship with the primary tumor lesion. In addition, our strategy allowed us to classify the tumor as DLBCL/HGBL-MYC/BCL2 entity. In clinical practice, such a minimally invasive approach provides a more sensitive tool than standard imaging and cell analyzing techniques, enabling more accurate disease monitoring and relapse prediction in particular cases.

• Klíčová slova
• Cell-free DNA, Central nervous system involvement, High-grade B-cell lymphoma, Integrative diagnostics, Next-generation sequencing,
• MeSH
• B-buněčný lymfom genetika   patologie   diagnóza   diagnostické zobrazování   MeSH
• cirkulující nádorová DNA genetika   MeSH
• difúzní velkobuněčný B-lymfom genetika   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• lokální recidiva nádoru patologie   genetika   MeSH
• magnetická rezonanční tomografie * MeSH
• nádorové biomarkery genetika   MeSH
• nádory centrálního nervového systému genetika   patologie   diagnostické zobrazování   MeSH
• vysoce účinné nukleotidové sekvenování * MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• cirkulující nádorová DNA MeSH
• nádorové biomarkery MeSH

Patients with testicular lymphoma are at an increased risk of central nervous system (CNS) disease. Optimal strategy for CNS relapse prevention is unknown. We analyzed treatment strategies, cumulative incidence of CNS relapse and prognosis in 229 patients with diffuse large B-cell lymphoma (DLBCL) and testicular involvement: 157 primary testicular lymphomas (PTL) in clinical stages IE/IIE and 72 patients in advanced stages (T-DLBCL) IIIE/IV. Treatments for PTL vs. T-DLBCL included: rituximab-based chemotherapy (80.9% vs. 90.3%), orchiectomy (94.3% vs. 65.3%) and contralateral testicular irradiation (59.8% vs. 44.4%). Majority (84.3%) received CNS prophylaxis with similar rates of prophylactic methotrexate (intravenous 19.1% vs. 16.6%, intrathecal 40.8% vs. 40.4%, or both 24.2% vs. 27.8%) between PTL and T-DLBCL (p = 0.89). Median follow-up was 51.8 months. CNS relapses occurred in 14 (6.1%) of 63 relapsing patients. The 5-year cumulative incidence of CNS relapse in PTL was 4.5% and in T-DLBCL 12.1%. Median time to CNS relapse was 21.9 months. In univariate analyses, orchiectomy was the single significant factor associated with lower risk of CNS relapse in PTL (HR = 0.11 [95% CI, 0-0.124], p = 0.001). Rituximab significantly reduced CNS relapse risk in T-DLBCL (HR = 0.1002, p = 0.0005). Median progression-free survival (PFS) and overall survival (OS) following CNS relapse was dismal in T-DLBCL compared to PTL (PFS 1.6 vs. 37.8 months, p = 0.04 and OS 2.3 vs. 37.8 months, p = 0.05). This study confirmed a favorable impact of rituximab in prevention of CNS relapse in T-DLBCL. Methotrexate prophylaxis did not alter CNS relapse risk. Prognosis of CNS relapse is particularly poor in T-DLBCL.

• Klíčová slova
• CNS relapse, Diffuse large B-cell lymphoma, Orchiectomy, Rituximab, Testicular involvement,
• MeSH
• difúzní velkobuněčný B-lymfom * terapie   epidemiologie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• methotrexát terapeutické užití   MeSH
• mladý dospělý MeSH
• nádory centrálního nervového systému * terapie   epidemiologie   prevence a kontrola   mortalita   MeSH
• následné studie MeSH
• orchiektomie MeSH
• prognóza MeSH
• protokoly antitumorózní kombinované chemoterapie terapeutické užití   MeSH
• retrospektivní studie MeSH
• rituximab * terapeutické užití   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• testikulární nádory * terapie   patologie   epidemiologie   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• methotrexát MeSH
• rituximab * MeSH

Recent studies highlighted genetic aberrations associated with prognosis in Mantle Cell lymphoma (MCL), yet comprehensive testing is not implemented in clinical routine. We conducted a comprehensive genomic characterization of 180 patients from the European MCL network trials by targeted sequencing of peripheral blood DNA using the EuroClonality(EC)-NDC assay. The IGH::CCND1 fusion was identified in 94% of patients, clonal IGH-V-(D)-J rearrangements in all, and 79% had ≥1 somatic gene mutation. The top mutated genes were ATM, TP53, KMT2D, SAMHD1, BIRC3 and NFKBIE. Copy number variations (CNVs) were detected in 83% of patients with RB1, ATM, CDKN2A/B and TP53 being the most frequently deleted and KLF2, CXCR4, CCND1, MAP2K1 and MYC the top amplified genes. CNVs and mutations were more frequently observed in older patients with adverse impact on prognosis. TP53mut, NOTCH1mut, FAT1mut TRAF2del, CDKN2A/Bdel and MAP2K1amp were linked to inferior failure-free (FFS) and overall survival (OS), while TRAF2mut, EGR2del and BCL2amp related to inferior OS only. Genetic complexity (≥3 CNVs) observed in 51% of analysed patients was significantly associated with impaired FFS and OS. We demonstrate that targeted sequencing from peripheral blood and bone marrow reliably detects diagnostically and prognostically important genetic factors in MCL patients, facilitating genetic characterization in clinical routine.

• MeSH
• dospělí MeSH
• genetické testování metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• lymfom z plášťových buněk * genetika   mortalita   MeSH
• mutace * MeSH
• nádorové biomarkery genetika   MeSH
• prognóza MeSH
• rizikové faktory MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• variabilita počtu kopií segmentů DNA * MeSH
• vysoce účinné nukleotidové sekvenování metody   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• nádorové biomarkery MeSH

Patients with chronic lymphocytic leukemia (CLL) exhibit diverse clinical outcomes. An expanding array of genetic tests is now employed to facilitate the identification of patients with high-risk disease and inform treatment decisions. These tests encompass molecular cytogenetic analysis, focusing on recurrent chromosomal alterations, particularly del(17p). Additionally, sequencing is utilized to identify TP53 mutations and to determine the somatic hypermutation status of the immunoglobulin heavy variable gene. Concurrently, a swift advancement of targeted treatment has led to the implementation of novel strategies for patients with CLL, including kinase and BCL2 inhibitors. This review explores both current and emerging diagnostic tests aimed at identifying high-risk patients who should benefit from targeted therapies. We outline existing treatment paradigms, emphasizing the importance of matching the right treatment to the right patient beyond genetic stratification, considering the crucial balance between safety and efficacy. We also take into consideration the practical and logistical issues when choosing a management strategy for each individual patient. Furthermore, we delve into the mechanisms underlying therapy resistance and stress the relevance of monitoring measurable residual disease to guide treatment decisions. Finally, we underscore the necessity of aggregating real-world data, adopting a global perspective, and ensuring patient engagement. Taken together, we argue that precision medicine is not the mere application of precision diagnostics and accessibility of precision therapies in CLL but encompasses various aspects of the patient journey (e.g., lifestyle exposures and comorbidities) and their preferences toward achieving true personalized medicine for patients with CLL.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Diffuse large B cell lymphoma of activated B cell type (ABC-DLBCL), a major cell-of-origin DLBCL subtype, is characterized by chronic active B cell receptor (BCR) signaling and NF-κB activation, which can be explained by activating mutations of the BCR signaling cascade in a minority of cases. We demonstrate that autonomous BCR signaling, akin to its essential pathogenetic role in chronic lymphocytic leukemia (CLL), can explain chronic active BCR signaling in ABC-DLBCL. 13 of 18 tested DLBCL-derived BCR, including 12 cases selected for expression of IgM, induced spontaneous calcium flux and increased phosphorylation of the BCR signaling cascade in murine triple knockout pre-B cells without antigenic stimulation or external BCR crosslinking. Autonomous BCR signaling was associated with IgM isotype, dependent on somatic BCR mutations and individual HCDR3 sequences, and largely restricted to non-GCB DLBCL. Autonomous BCR signaling represents a novel immunological oncogenic driver mechanism in DLBCL originating from individual BCR sequences and adds a new dimension to currently proposed genetics- and transcriptomics-based DLBCL classifications.

• MeSH
• B-lymfocyty MeSH
• chronická lymfatická leukemie * MeSH
• difúzní velkobuněčný B-lymfom * genetika   MeSH
• imunoglobulin M MeSH
• myši MeSH
• receptory antigenů B-buněk MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• imunoglobulin M MeSH
• receptory antigenů B-buněk MeSH

• MeSH
• difúzní velkobuněčný B-lymfom * farmakoterapie   patologie   MeSH
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

B-cell receptor (BCR) is a B cell hallmark surface complex regulating multiple cellular processes in normal as well as malignant B cells. Igα (CD79a)/Igβ (CD79b) are essential components of BCR that are indispensable for its functionality, signal initiation, and signal transduction. CD79a/CD79b-mediated BCR signaling is required for the survival of normal as well as malignant B cells via a wide signaling network. Recent studies identified the great complexity of this signaling network and revealed the emerging role of CD79a/CD79b in signal integration. In this review, we have focused on functional features of CD79a/CD79b, summarized signaling consequences of CD79a/CD79b post-translational modifications, and highlighted specifics of CD79a/CD79b interactions within BCR and related signaling cascades. We have reviewed the complex role of CD79a/CD79b in multiple aspects of normal B cell biology and how is the normal BCR signaling affected by lymphoid neoplasms associated CD79A/CD79B mutations. We have also summarized important unresolved questions and highlighted issues that remain to be explored for better understanding of CD79a/CD79b-mediated signal transduction and the eventual identification of additional therapeutically targetable BCR signaling vulnerabilities.

• Klíčová slova
• B cell development, B lymphocytes, B-cell receptor, BCR, BCR assembly, BCR internalization, BCR signaling, BTK, CD79a, CD79b, CLL, DLBCL, ITAM, LYN, NHL, antigen-induced BCR signaling, immunoglobulin, lymphoid malignancies, malignant B cells, non-Hodgkin lymphoma, tonic BCR signaling,
• MeSH
• buněčná membrána MeSH
• kognice MeSH
• mutace MeSH
• receptory antigenů B-buněk * genetika   MeSH
• signální transdukce * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• receptory antigenů B-buněk * MeSH

Current classifications (World Health Organization-HAEM5/ICC) define up to 26 molecular B-cell precursor acute lymphoblastic leukemia (BCP-ALL) disease subtypes by genomic driver aberrations and corresponding gene expression signatures. Identification of driver aberrations by transcriptome sequencing (RNA-Seq) is well established, while systematic approaches for gene expression analysis are less advanced. Therefore, we developed ALLCatchR, a machine learning-based classifier using RNA-Seq gene expression data to allocate BCP-ALL samples to all 21 gene expression-defined molecular subtypes. Trained on n = 1869 transcriptome profiles with established subtype definitions (4 cohorts; 55% pediatric / 45% adult), ALLCatchR allowed subtype allocation in 3 independent hold-out cohorts (n = 1018; 75% pediatric / 25% adult) with 95.7% accuracy (averaged sensitivity across subtypes: 91.1% / specificity: 99.8%). High-confidence predictions were achieved in 83.7% of samples with 98.9% accuracy. Only 1.2% of samples remained unclassified. ALLCatchR outperformed existing tools and identified novel driver candidates in previously unassigned samples. Additional modules provided predictions of samples blast counts, patient's sex, and immunophenotype, allowing the imputation in cases where these information are missing. We established a novel RNA-Seq reference of human B-lymphopoiesis using 7 FACS-sorted progenitor stages from healthy bone marrow donors. Implementation in ALLCatchR enabled projection of BCP-ALL samples to this trajectory. This identified shared proximity patterns of BCP-ALL subtypes to normal lymphopoiesis stages, extending immunophenotypic classifications with a novel framework for developmental comparisons of BCP-ALL. ALLCatchR enables RNA-Seq routine application for BCP-ALL diagnostics with systematic gene expression analysis for accurate subtype allocation and novel insights into underlying developmental trajectories.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: Approximately 40% of patients with diffuse large B-cell lymphoma (DLBCL) experience treatment resistance to the first-line R-CHOP regimen. ATP binding cassette (ABC) transporters and survivin might play a role in multidrug resistance (MDR) in various tumors. The aim was to investigate if the coexpression of ABC transporters and survivin was associated with R-CHOP treatment response. METHODS: The expression of Bcl-2, survivin, P-glycoprotein/ABCB1, MRP1/ABCC1, and BCRP/ABCC2 was analyzed using immunohistochemistry in tumor specimens obtained from patients with DLBCL, and classified according to the treatment response as Remission, Relapsed, and (primary) Refractory groups. All patients received R-CHOP or equivalent treatment. RESULTS: Bcl-2 was in strong positive correlation with clinical parameters and all biomarkers except P-gp/ABCB1. The overexpression of MRP1/ABCC1, survivin, and BCRP/ABCC2 presented as high immunoreactive scores (IRSs) was detected in the Refractory and Relapsed groups (p < 0.05 vs. Remission), respectively, whereas the IRS of P-gp/ABCB1 was low. Significant correlations were found among either MRP1/ABCC1 and survivin or BCRP/ABCC2 in the Refractory and Relapsed groups, respectively. In multiple linear regression analysis, ECOG status along with MRP1/ABCC1 or survivin and BRCP/ABCG2 was significantly associated with the prediction of the R-CHOP treatment response. CONCLUSIONS: DLBCL might harbor certain molecular signatures such as MRP1/ABCC1, survivin, and BCRP/ABCC2 overexpression that can predict resistance to R-CHOP.

• Klíčová slova
• BCRP/ABCC2, MRP1/ABCC1, multidrug resistance, non-Hodgkin lymphoma, survivin,
• Publikační typ
• časopisecké články MeSH