TY - JOUR A1 - Aukema, Sietse M. A1 - Kreuz, Markus A1 - Kohler, Christian W. A1 - Rosolowski, Maciej A1 - Hasenclever, Dirk A1 - Hummel, Michael A1 - Küppers, Ralf A1 - Lenze, Diddo A1 - Ott, German A1 - Pott, Christiane A1 - Richter, Julia A1 - Rosenwald, Andreas A1 - Szczepanowski, Monika A1 - Schwaenen, Carsten A1 - Stein, Harald A1 - Trautmann, Heiko A1 - Wessendorf, Swen A1 - Trümper, Lorenz A1 - Loeffler, Markus A1 - Spang, Rainer A1 - Kluin, Philip M. A1 - Klapper, Wolfram A1 - Siebert, Reiner T1 - Biological characterization of adult MYC-translocation-positive mature B-cell lymphomas other than molecular Burkitt lymphoma JF - Haematologica N2 - Chromosomal translocations affecting the MYC oncogene are the biological hallmark of Burkitt lymphomas but also occur in a subset of other mature B-cell lymphomas. If accompanied by a chromosomal break targeting the BCL2 and/or BCL6 oncogene these MYC translocation-positive (MYC+) lymphomas are called double-hit lymphomas, otherwise the term single-hit lymphomas is applied. In order to characterize the biological features of these MYC+ lymphomas other than Burkitt lymphoma we explored, after exclusion of molecular Burkitt lymphoma as defined by gene expression profiling, the molecular, pathological and clinical aspects of 80 MYC-translocation-positive lymphomas (31 single-hit, 46 double-hit and 3 MYC+-lymphomas with unknown BCL6 status). Comparison of single-hit and double-hit lymphomas revealed no difference in MYC partner (IG/non-IG), genomic complexity, MYC expression or gene expression profile. Double-hit lymphomas more frequently showed a germinal center B-cell-like gene expression profile and had higher IGH and MYC mutation frequencies. Gene expression profiling revealed 130 differentially expressed genes between BCL6(+)/MYC+ and BCL2(+)/MYC+ double-hit lymphomas. BCL2(+)/MYC+ double-hit lymphomas more frequently showed a germinal center B-like gene expression profile. Analysis of all lymphomas according to MYC partner (IG/non-IG) revealed no substantial differences. In this series of lymphomas, in which immunochemotherapy was administered in only a minority of cases, single-hit and double-hit lymphomas had a similar poor outcome in contrast to the outcome of molecular Burkitt lymphoma and lymphomas without the MYC break. Our data suggest that, after excluding molecular Burkitt lymphoma and pediatric cases, MYC+ lymphomas are biologically quite homogeneous with single-hit and double-hit lymphomas as well as IG-MYC and non-IG-MYC+ lymphomas sharing various molecular characteristics. KW - Rituximab plus KW - cyclophsophamide KW - c-myc KW - gene expression KW - genomic aberrations KW - follicular lymphoma KW - prognostic factor KW - poor prognosis KW - grade 3B KW - distinct Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-116882 SN - 1592-8721 VL - 99 IS - 4 ER - TY - JOUR A1 - Rouhigharabaei, Leila A1 - Ferreiro, Julio Finalet A1 - Tousseyn, Thomas A1 - van der Krogt, Jo-Anne A1 - Put, Natalie A1 - Haralambieva, Eugenia A1 - Graux, Carlos A1 - Maes, Brigitte A1 - Vicente, Carmen A1 - Vandenberghe, Peter A1 - Cools, Jan A1 - Wlodarska, Iwona T1 - Non-IG Aberrations of FOXP1 in B-Cell Malignancies Lead to an Aberrant Expression of N-Truncated Isoforms of FOXP1 JF - PLOS ONE N2 - The transcription factor FOXP1 is implicated in the pathogenesis of B-cell lymphomas through chromosomal translocations involving either immunoglobulin heavy chain (IGH) locus or non-IG sequences. The former translocation, t(3; 14)(p13; q32), results in dysregulated expression of FOXP1 juxtaposed with strong regulatory elements of IGH. Thus far, molecular consequences of rare non-IG aberrations of FOXP1 remain undetermined. Here, using molecular cytogenetics and molecular biology studies, we comprehensively analyzed four lymphoma cases with non-IG rearrangements of FOXP1 and compared these with cases harboring t(3; 14)(p13; q32)/IGH-FOXP1 and FOXP1-expressing lymphomas with no apparent structural aberrations of the gene. Our study revealed that non-IG rearrangements of FOXP1 are usually acquired during clinical course of various lymphoma subtypes, including diffuse large B cell lymphoma, marginal zone lymphoma and chronic lymphocytic leukemia, and correlate with a poor prognosis. Importantly, these aberrations constantly target the coding region of FOXP1, promiscuously fusing with coding and non-coding gene sequences at various reciprocal breakpoints (2q36, 10q24 and 3q11). The non-IG rearrangements of FOXP1, however, do not generate functional chimeric genes but commonly disrupt the full-length FOXP1 transcript leading to an aberrant expression of N-truncated FOXP1 isoforms (FOXP1NT), as shown by QRT-PCR and Western blot analysis. In contrast, t(3; 14)(p13; q32)/IGH-FOXP1 affects the 59 untranslated region of FOXP1 and results in overexpress the full-length FOXP1 protein (FOXP1FL). RNA-sequencing of a few lymphoma cases expressing FOXP1NT and FOXP1FL detected neither FOXP1-related fusions nor FOXP1 mutations. Further bioinformatic analysis of RNA-sequencing data retrieved a set of genes, which may comprise direct or non-direct targets of FOXP1NT, potentially implicated in disease progression. In summary, our findings point to a dual mechanism through which FOXP1 is implicated in B-cell lymphomagenesis. We hypothesize that the primary t(3; 14)(p13; q32)/IGH-FOXP1 activates expression of the FOXP1FL protein with potent oncogenic activity, whereas the secondary non-IG rearrangements of FOXP1 promote expression of the FOXP1NT proteins, likely driving progression of disease. KW - lymphoid-tissue lymphomas KW - acute lymphoblastic leukemia KW - transcription factor FOXP1 KW - cardiomyocyte proliferation KW - chromosomal aberration KW - prostate cancer KW - down regulation KW - poor prognosis KW - malt lymphoma KW - gene Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-117679 SN - 1932-6203 VL - 9 IS - 1 ER -