• MeSH
• finanční podpora výzkumu jako téma MeSH
• folikulární lymfom genetika   krev   patologie   MeSH
• geny bcl-2 genetika   MeSH
• kostní dřeň chemie   MeSH
• lidé MeSH
• nehodgkinský lymfom MeSH
• přežití MeSH
• prognóza MeSH
• progrese nemoci MeSH
• statistika jako téma MeSH
• translokace genetická genetika   MeSH
• Check Tag
• lidé MeSH

• MeSH
• DNA nádorová analýza   MeSH
• dospělí MeSH
• finanční podpora výzkumu jako téma MeSH
• lidé MeSH
• lymfoidní leukemie genetika   MeSH
• přestavba genů pro těžké řetězce B-lymfocytů genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• Publikační typ
• srovnávací studie MeSH

• MeSH
• B-lymfocyty metabolismus   MeSH
• chronická lymfatická leukemie genetika   MeSH
• imunofenotypizace metody   MeSH
• lidé MeSH
• přestavba genů pro těžké řetězce B-lymfocytů genetika   MeSH
• těžké řetězce imunoglobulinů genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• dopisy MeSH
• práce podpořená grantem MeSH

To confirm a diagnosis of malignant lymphomas it is imperative to distinguish between reactive and neoplastic proliferation. The PCR (polymerase chain reaction) is a method that can be used for detection of clonal rearrangements of the immunoglobulin heavy chain (IgH) and T-cell receptor (TCR) genes. This study summarizes the outcomes of PCR analysis of IgH and TCR gene rearrangements in 91 bioptic cases of lymphoproliferative disorders. In the class of B lymphomas we detected clonal IgH rearrangement in nearly 83% of cases and in class of T lymphomas in 81% of cases. We can affirm that PCR analysis of B and T cell clonality on DNA extracted from the whole section of formalin-fixed, paraffin-embedded tissue is very suitable for routinely elaborate this. Its influence on the diagnostics of morphological unclear cases in particular, is crucial and is useful in establishing a diagnosis of lymphoid neoplasias in specimens in which histological and immunophenotypic studies are inconclusive.

• MeSH
• financování organizované MeSH
• fixativa MeSH
• formaldehyd MeSH
• genová přestavba T-lymfocytů MeSH
• lidé MeSH
• lymfoproliferativní nemoci diagnóza   genetika   MeSH
• polymerázová řetězová reakce MeSH
• přestavba genů pro těžké řetězce B-lymfocytů MeSH
• zalévání tkání do parafínu MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• hodnotící studie MeSH

One of the hallmarks of B lymphoid malignancies is a B cell clone characterized by a unique footprint of clonal immunoglobulin (IG) gene rearrangements that serves as a diagnostic marker for clonality assessment. The EuroClonality/BIOMED-2 assay is currently the gold standard for analyzing IG heavy chain (IGH) and κ light chain (IGK) gene rearrangements of suspected B cell lymphomas. Here, the EuroClonality-NGS Working Group presents a multicentre technical feasibility study of a novel approach involving next-generation sequencing (NGS) of IGH and IGK loci rearrangements that is highly suitable for detecting IG gene rearrangements in frozen and formalin-fixed paraffin-embedded tissue specimens. By employing gene-specific primers for IGH and IGK amplifying smaller amplicon sizes in combination with deep sequencing technology, this NGS-based IG clonality analysis showed robust performance, even in DNA samples of suboptimal DNA integrity, and a high clinical sensitivity for the detection of clonal rearrangements. Bioinformatics analyses of the high-throughput sequencing data with ARResT/Interrogate, a platform developed within the EuroClonality-NGS Working Group, allowed accurate identification of clonotypes in both polyclonal cell populations and monoclonal lymphoproliferative disorders. This multicentre feasibility study is an important step towards implementation of NGS-based clonality assessment in clinical practice, which will eventually improve lymphoma diagnostics.

• MeSH
• B-buněčný lymfom genetika   MeSH
• genová přestavba genetika   MeSH
• geny pro imunoglobuliny genetika   MeSH
• imunoglobuliny - kappa-řetězce genetika   MeSH
• lidé MeSH
• lymfoproliferativní nemoci genetika   MeSH
• studie proveditelnosti MeSH
• těžké řetězce imunoglobulinů genetika   MeSH
• vysoce účinné nukleotidové sekvenování metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• B-lymfocyty imunologie   metabolismus   MeSH
• buněčné klony imunologie   metabolismus   MeSH
• lidé MeSH
• lymfoproliferativní nemoci diagnóza   imunologie   MeSH
• přestavba genů pro těžké řetězce B-lymfocytů imunologie   MeSH
• reziduální nádor genetika   MeSH
• variabilní oblast imunoglobulinu genetika   MeSH
• Check Tag
• lidé MeSH

INTRODUCTION: The malignant transformation leading to a maturation arrest in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) occurs early in B-cell development, in a pro-B or pre-B cell, when somatic recombination of variable (V), diversity (D), and joining (J) segment immunoglobulin (IG) genes and the B-cell rescue mechanism of VH replacement might be ongoing or fully active, driving clonal evolution. In this study of newly diagnosed BCP-ALL, we sought to understand the mechanistic details of oligoclonal composition of the leukemia at diagnosis, clonal evolution during follow-up, and clonal distribution in different hematopoietic compartments. METHODS: Utilizing high-throughput sequencing assays and bespoke bioinformatics we identified BCP-ALL-derived clonally-related IGH sequences by their shared 'DNJ-stem'. RESULTS: We introduce the concept of 'marker DNJ-stem' to cover the entirety of, even lowly abundant, clonally-related family members. In a cohort of 280 adult patients with BCP-ALL, IGH clonal evolution at diagnosis was identified in one-third of patients. The phenomenon was linked to contemporaneous recombinant and editing activity driven by aberrant ongoing DH/VH-DJH recombination and VH replacement, and we share insights and examples for both. Furthermore, in a subset of 167 patients with molecular subtype allocation, high prevalence and high degree of clonal evolution driven by ongoing DH/VH-DJH recombination were associated with the presence of KMT2A gene rearrangements, while VH replacements occurred more frequently in Ph-like and DUX4 BCP-ALL. Analysis of 46 matched diagnostic bone marrow and peripheral blood samples showed a comparable clonal and clonotypic distribution in both hematopoietic compartments, but the clonotypic composition markedly changed in longitudinal follow-up analysis in select cases. Thus, finally, we present cases where the specific dynamics of clonal evolution have implications for both the initial marker identification and the MRD monitoring in follow-up samples. DISCUSSION: Consequently, we suggest to follow the marker DNJ-stem (capturing all family members) rather than specific clonotypes as the MRD target, as well as to follow both VDJH and DJH family members since their respective kinetics are not always parallel. Our study further highlights the intricacy, importance, and present and future challenges of IGH clonal evolution in BCP-ALL.

• MeSH
• Burkittův lymfom * genetika   MeSH
• dospělí MeSH
• geny pro imunoglobuliny MeSH
• kostní dřeň patologie   MeSH
• lidé MeSH
• polymerázová řetězová reakce MeSH
• pre-B-buněčná leukemie * diagnóza   genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Follicular lymphoma (FL) is highly associated with the molecular rearrangement BCL2/IGH. Although BCL2/IGH has been studied many times in follicular lymphoma, its real clinical value remains controversial. In this study, we performed quantitative testing by real-time polymerase chain reaction in 56 FL patients with median follow-up of 44 months (range, 9-102 months); chemotherapy was administered in 52 of 56 cases. Pretreatment numbers of BCL2/IGH varied in wide ranges, with a median of 2947 (range, 0-1,261,013) copies/10(6) cellular equivalent in peripheral blood (PB) and 4650 copies/10(6) cellular equivalent (range, 1-1,056,813) in bone marrow (BM), the difference between PB and BM was significant (p = 0.006). Pretreatment of BCL2/IGH quantities were correlated to clinical parameters (e.g., age, stage, sex, lactate dehydrogenase, B symptoms, grade, bulky disease, chemotherapy regimen) and to progression free-survival. Advanced clinical stage (III and IV) and microscopic BM involvement were significantly associated with higher numbers of BCL2/IGH in PB (p < 0.05) and in BM (p = 0.05), regardless all or newly diagnosed patients were evaluated. High pretreatment burden of BCL2/IGH was associated with significantly shorter progression-free survival; p = 0.003 and p = 0.047 for PB and BM, respectively. In conclusion, pretreatment quantity of BCL2/IGH in PB or BM seems to mirror the extent of disease and can provide an auxiliary prognostic parameter in FL. Our results also support evidence of the negative prognostic value of microscopic BM involvement in FL.

• MeSH
• dospělí MeSH
• folikulární lymfom krev   farmakoterapie   genetika   mortalita   MeSH
• fúzní onkogenní proteiny MeSH
• kostní dřeň metabolismus   patologie   MeSH
• kvantitativní polymerázová řetězová reakce metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• míra přežití MeSH
• následné studie MeSH
• přežití po terapii bez příznaků nemoci MeSH
• protoonkogenní proteiny c-bcl-2 MeSH
• retrospektivní studie MeSH
• RNA nádorová krev   genetika   MeSH
• senioři MeSH
• těžké řetězce imunoglobulinů MeSH
• translokace genetická MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky MeSH
• práce podpořená grantem MeSH

• Publikační typ
• časopisecké články MeSH

The current mammalian paradigm states that 1) rearrangements in the IgH locus precede those in IgL loci, 2) IgLλ genes rearrange only when IgLκ genes are consumed, and 3) the surrogate L chain is necessary for selection of productive IgH gene rearrangements. We show in swine that IgL rearrangements precede IgH gene rearrangements, resulting in the expression of naked IgL on a surface of precursor B cells. Findings also suggest that there is no dependency on the surrogate L chain, and thus the authentic IgL proteins may be used for selection of the IgH repertoire. Although rearrangement starts with IgLκ genes, it is rapidly replaced by IgLλ rearrangement. Fast replacement is characterized by occurrence of IgLλ(lo)IgLκ(lo) dual-expressing precursors in which IgLκ expression is a remnant of a previous translation. Most IgLκ(+) B cells are then generated later, indicating that there are two waves of IgLκ synthesis in different developmental stages with IgLλ gene rearrangements in between. In the absence of stromal cells, the stepwise order of rearrangements is blocked so that IgLλ gene rearrangements predominate in early B cell development. To our knowledge, this is the first evidence that some mammals can use an inverted order of Ig loci rearrangement. Moreover, a situation in which the generation of BCR-bearing IgLκ is delayed until after IgLλ becomes the dominant isotype may help explain the extreme deviations in the IgLκ/IgLλ ratios among mammals.

• MeSH
• B-lymfocyty imunologie   fyziologie   MeSH
• geny pro imunoglobuliny MeSH
• imunoglobuliny - kappa-řetězce genetika   MeSH
• lehké řetězce imunoglobulinů genetika   imunologie   MeSH
• prasata MeSH
• přestavba genů pro lehké řetězce B-lymfocytů * MeSH
• přestavba genů pro těžké řetězce B-lymfocytů MeSH
• receptory antigenů B-buněk genetika   imunologie   MeSH
• těžké řetězce imunoglobulinů genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH