1. Diffuse large B-cell lymphomas in adults with aberrant coexpression of CD10, BCL6, and MUM1 are enriched in IRF4 rearrangements
- Author
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Barbara Mankel, Colleen Ramsower, Leonie Frauenfeld, Franziska Otto, Itziar Salaverria, Falko Fend, Magda Pinyol, Natalia Castrejon-de-Anta, Olga Balagué, Julia Salmeron-Villalobos, Annika Katharina Mayer, Elias Campo, Lisa M. Rimsza, Sebastian Streich, Julia Steinhilber, Joan Enric Ramis-Zaldivar, Leticia Quintanilla-Martinez, and Irina Bonzheim
- Subjects
Adult ,Limfomes ,Chromosomal translocation ,Semaphorins ,Biology ,Translocation, Genetic ,Genètica mèdica ,Antigens, CD ,immune system diseases ,hemic and lymphatic diseases ,medicine ,Humans ,Child ,In Situ Hybridization, Fluorescence ,B cell ,Gene Rearrangement ,Genetic heterogeneity ,Medical genetics ,Germinal center ,Hematology ,CD79B ,medicine.disease ,BCL6 ,Molecular biology ,Lymphoma ,Gene expression profiling ,medicine.anatomical_structure ,Proto-Oncogene Proteins c-bcl-2 ,Interferon Regulatory Factors ,Myeloid Differentiation Factor 88 ,Proto-Oncogene Proteins c-bcl-6 ,Lymphomas ,Lymphoma, Large B-Cell, Diffuse - Abstract
Diffuse large B-cell lymphoma (DLBCL) with aberrant coexpression of CD10+BCL6+MUM1+ (DLBCL-AE), classified as germinal center B cell (GCB) type by the Hans algorithm (HA), was genetically characterized. To capture the complexity of DLBCL-AE, we used an integrated approach that included gene expression profiling (GEP), fluorescence in situ hybridization, targeted gene sequencing, and copy number (CN) arrays. According to GEP, 32/54 (59%) cases were classified as GCB-DLBCL, 16/54 (30%) as activated B-cell (ABC) DLBCL, and 6/54 (11%) as unclassifiable. The discrepancy between HA and GEP was 41%. Three genetic subgroups were identified. Group 1 included 13/50 (26%) cases without translocations and mainly showing and ABC/MCD molecular profile. Group 2 comprised 11/50 (22%) cases with IRF4 alterations (DLBCL-IRF4), frequent mutations in IRF4 (82%) and NF-κB pathway genes (MYD88, CARD11, and CD79B), and losses of 17p13.2. Five cases each were classified as GCB- or ABC-type. Group 3 included 26/50 (52%) cases with 1 or several translocations in BCL2/BCL6/MYC/IGH, and GCB/EZB molecular profile predominated. Two cases in this latter group showed complex BCL2/BCL6/IRF4 translocations. DLBCL-IRF4 in adults showed a similar copy number profile and shared recurrent CARD11 and CD79B mutations when compared with LBCL-IRF4 in the pediatric population. However, adult cases showed higher genetic complexity, higher mutational load with frequent MYD88 and KMT2D mutations, and more ABC GEP. IRF4 mutations were identified only in IRF4-rearranged cases, indicating its potential use in the diagnostic setting. In conclusion, DLBCL-AE is genetically heterogeneous and enriched in cases with IRF4 alterations. DLBCL-IRF4 in adults has many similarities to the pediatric counterpart.
- Published
- 2022
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