51
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Farfsing A, Engel F, Seiffert M, Hartmann E, Ott G, Rosenwald A, Stilgenbauer S, Döhner H, Boutros M, Lichter P, Pscherer A. Gene knockdown studies revealed CCDC50 as a candidate gene in mantle cell lymphoma and chronic lymphocytic leukemia. Leukemia 2009; 23:2018-26. [PMID: 19641524 DOI: 10.1038/leu.2009.144] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The two B-cell non-Hodgkin's lymphoma entities, chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL), show recurrent chromosomal gains of 3q25-q29, 12q13-q14 and 18q21-q22. The pathomechanisms affected by these aberrations are not understood. The aim of this study was to identify genes, located within these gained regions, which control cell death and cell survival of MCL and CLL cancer cells. Blood samples collected from 18 patients with CLL and 6 patients with MCL, as well as 6 cell lines representing both malignancies were analyzed by gene expression profiling. By a comparison of genomic DNA and gene expression, 72 candidate genes were identified. We performed a limited RNA interference screening with these candidates to identify genes affecting cell survival. CCDC50 (coiled coil domain containing protein 50), SERPINI2 and SMARCC2 mediated a reduction of cell viability in primary CLL cells as well as in cell lines. Gene knockdown and a nuclear factor kappa B (NFkappaB) reporter gene assay revealed that CCDC50 is required for survival in MCL and CLL cells and controls NFkappaB signaling.
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52
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Schannwell C, Ott G, Strauer B. Therapeutisches Potenzial der Stammzelltherapie bei Herz- und Gefäßerkrankungen. Internist (Berl) 2009. [DOI: 10.1007/s00108-009-2359-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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53
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Husemann K, Biehl K, Ott G, Friedel G, Kohlhäufl M. Fallbericht pulmonal noduläre Amyloidose – seltene DD eines pulmonalen Rundherdes. Pneumologie 2009. [DOI: 10.1055/s-0029-1214022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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54
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Hutter G, Scheubner M, Ott G, Zimmermann Y, Hübler K, Roth S, Stilgenbauer S, Kalla J, Stöcklein H, Hiddemann W, Dreyling M. Allelic genotyping reveals a hierarchy of genomic alterations in mantle cell lymphoma associated to cell proliferation. Ann Hematol 2009; 88:821-8. [DOI: 10.1007/s00277-008-0686-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Accepted: 12/18/2008] [Indexed: 10/21/2022]
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55
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Webendörfer S, Ott G, Zober A. Arbeitsmedizinische Vorsorge bei Mitarbeitern in einer neu eingerichteten Phytaseproduktion. Pneumologie 2008. [DOI: 10.1055/s-0028-1108024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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56
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Lenz G, Wright G, Dave SS, Xiao W, Powell J, Zhao H, Xu W, Tan B, Goldschmidt N, Iqbal J, Vose J, Bast M, Fu K, Weisenburger DD, Greiner TC, Armitage JO, Kyle A, May L, Gascoyne RD, Connors JM, Troen G, Holte H, Kvaloy S, Dierickx D, Verhoef G, Delabie J, Smeland EB, Jares P, Martinez A, Lopez-Guillermo A, Montserrat E, Campo E, Braziel RM, Miller TP, Rimsza LM, Cook JR, Pohlman B, Sweetenham J, Tubbs RR, Fisher RI, Hartmann E, Rosenwald A, Ott G, Muller-Hermelink HK, Wrench D, Lister TA, Jaffe ES, Wilson WH, Chan WC, Staudt LM. Stromal gene signatures in large-B-cell lymphomas. N Engl J Med 2008; 359:2313-23. [PMID: 19038878 PMCID: PMC9103713 DOI: 10.1056/nejmoa0802885] [Citation(s) in RCA: 1332] [Impact Index Per Article: 83.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND The addition of rituximab to combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), or R-CHOP, has significantly improved the survival of patients with diffuse large-B-cell lymphoma. Whether gene-expression signatures correlate with survival after treatment of diffuse large-B-cell lymphoma is unclear. METHODS We profiled gene expression in pretreatment biopsy specimens from 181 patients with diffuse large-B-cell lymphoma who received CHOP and 233 patients with this disease who received R-CHOP. A multivariate gene-expression-based survival-predictor model derived from a training group was tested in a validation group. RESULTS A multivariate model created from three gene-expression signatures--termed "germinal-center B-cell," "stromal-1," and "stromal-2"--predicted survival both in patients who received CHOP and patients who received R-CHOP. The prognostically favorable stromal-1 signature reflected extracellular-matrix deposition and histiocytic infiltration. By contrast, the prognostically unfavorable stromal-2 signature reflected tumor blood-vessel density. CONCLUSIONS Survival after treatment of diffuse large-B-cell lymphoma is influenced by differences in immune cells, fibrosis, and angiogenesis in the tumor microenvironment.
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MESH Headings
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal, Murine-Derived
- Antineoplastic Combined Chemotherapy Protocols
- Cyclophosphamide
- Disease Progression
- Doxorubicin
- Extracellular Matrix/genetics
- Gene Expression
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Genes, MHC Class II
- Germinal Center
- Humans
- Immunologic Factors/administration & dosage
- Kaplan-Meier Estimate
- Lymphoma, Large B-Cell, Diffuse/drug therapy
- Lymphoma, Large B-Cell, Diffuse/genetics
- Lymphoma, Large B-Cell, Diffuse/mortality
- Lymphoma, Large B-Cell, Diffuse/pathology
- Middle Aged
- Multivariate Analysis
- Neovascularization, Pathologic/genetics
- Prednisone
- Prognosis
- Rituximab
- Stromal Cells/metabolism
- Stromal Cells/pathology
- Vincristine
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57
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Klapper W, Stoecklein H, Zeynalova S, Ott G, Kosari F, Rosenwald A, Loeffler M, Trümper L, Pfreundschuh M, Siebert R. Structural aberrations affecting the MYC locus indicate a poor prognosis independent of clinical risk factors in diffuse large B-cell lymphomas treated within randomized trials of the German High-Grade Non-Hodgkin's Lymphoma Study Group (DSHNHL). Leukemia 2008; 22:2226-9. [PMID: 18754028 DOI: 10.1038/leu.2008.230] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent retrospective studies of heterogeneously treated patients have suggested that chromosomal aberrations of the MYC gene locus indicate an unfavorable prognosis in diffuse large B-cell lymphoma (DLBCL). Here, we investigated the prognostic impact of MYC aberrations analyzed by interphase fluorescence in situ hybridization in 177 patients with de novo DLBCL treated within the two prospective, randomized trials non-Hodgkin's lymphoma NHL-B1 and NHL-B2. MYC aberrations were detected in 14 DLBCL (7.9%). In a univariate analysis compared with MYC-negative DLBCL, MYC-positive cases showed a significantly shorter overall survival (OS) (P=0.047) and relevantly, though not significantly, shorter event-free survival (EFS) (P=0.062). In a Cox model adjusted for the international prognostic index, the presence of a MYC gene rearrangement was the strongest statistically independent predictor of OS (relative risk 3.4, P=0.004) and EFS (relative risk 2.5, P=0.015), and this also held true when the cell-of-origin signature detected by immunohistochemistry was included in the model.
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58
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Rosenwald A, Ott G. Burkitt lymphoma versus diffuse large B-cell lymphoma. Ann Oncol 2008; 19 Suppl 4:iv67-9. [PMID: 18519409 DOI: 10.1093/annonc/mdn201] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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59
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Bentink S, Wessendorf S, Schwaenen C, Rosolowski M, Klapper W, Rosenwald A, Ott G, Banham AH, Berger H, Feller AC, Hansmann ML, Hasenclever D, Hummel M, Lenze D, Möller P, Stuerzenhofecker B, Loeffler M, Truemper L, Stein H, Siebert R, Spang R. Pathway activation patterns in diffuse large B-cell lymphomas. Leukemia 2008; 22:1746-54. [PMID: 18580954 DOI: 10.1038/leu.2008.166] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Deregulation of cell signaling pathways controlling cell growth and cell survival is a common feature of all cancers. Although a core repertoire of oncogenic mechanisms is widely conserved between various malignancies, the constellation of pathway activities can vary even in patients with the same malignant disease. Modern molecularly targeted cancer drugs intervene in cell signaling compensating for pathway deregulation. Hence characterizing tumors with respect to pathway activation will become crucial for treatment decisions. Here we have used semi-supervised machine learning methodology to generate signatures of eight oncogene-inducible pathways, which are conserved across epithelial and lymphoid tissues. We combined them to patterns of pathway activity called PAPs for pathway activation patterns and searched for them in 220 morphologically, immunohistochemically and genetically well-characterized mature aggressive B-cell lymphomas including 134 cases with clinical data available. Besides Burkitt lymphoma, which was characterized by a unique pattern, the PAPs identified four distinct groups of mature aggressive B-cell lymphomas across independent gene expression studies with distinct biological characteristics, genetic aberrations and prognosis. We confirmed our findings through cross-platform analysis in an independent data set of 303 mature aggressive B-cell lymphomas.
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60
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61
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Dierlamm J, Murga Penas EM, Bentink S, Wessendorf S, Berger H, Hummel M, Klapper W, Lenze D, Rosenwald A, Haralambieva E, Ott G, Cogliatti SB, Moller P, Schwaenen C, Stein H, Loffler M, Spang R, Trumper L, Siebert R. Gain of chromosome region 18q21 including the MALT1 gene is associated with the activated B-cell-like gene expression subtype and increased BCL2 gene dosage and protein expression in diffuse large B-cell lymphoma. Haematologica 2008; 93:688-96. [DOI: 10.3324/haematol.12057] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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62
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Sander S, Bullinger L, Leupolt E, Benner A, Kienle D, Katzenberger T, Kalla J, Ott G, Muller-Hermelink HK, Barth TF, Moller P, Lichter P, Dohner H, Stilgenbauer S. Genomic aberrations in mantle cell lymphoma detected by interphase fluorescence in situ hybridization. Incidence and clinicopathological correlations. Haematologica 2008; 93:680-7. [DOI: 10.3324/haematol.12330] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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63
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Schmidt T, Eulenbruch H, Wechselberger J, Kohlhäufl M, Ott G, Zoeppritz V. Diffuse Lungeninfiltration bei Morbus Waldenstroem. Pneumologie 2008. [DOI: 10.1055/s-2008-1074186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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64
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Ott G, Ott C. Study on the Effectiveness of Trazodone in the Treatment of Endogenous Depression. Pharmacokinetic and Psychopathometric Investigations. PHARMACOPSYCHIATRY 2008. [DOI: 10.1055/s-2007-1017321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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65
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Ott G, Kaymak H, Mester U. Funktionstraining nach Multifokallinsen-Implantation. Klin Monbl Augenheilkd 2008. [DOI: 10.1055/s-2008-1057998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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66
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Adam P, Haralambieva E, Hartmann M, Mao Z, Ott G, Rosenwald A. Rare occurrence of IgVH gene translocations and restricted IgVH gene repertoire in ocular MALT-type lymphoma. Haematologica 2008; 93:319-20. [DOI: 10.3324/haematol.11950] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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67
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Leich E, Haralambieva E, Zettl A, Chott A, Rüdiger T, Höller S, Müller-Hermelink HK, Ott G, Rosenwald A. Tissue microarray-based screening for chromosomal breakpoints affecting the T-cell receptor gene loci in mature T-cell lymphomas. J Pathol 2007; 213:99-105. [PMID: 17582237 DOI: 10.1002/path.2196] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The pathogenesis of mature T-cell non-Hodgkin lymphomas (T-NHLs) is poorly understood. Analogous to B-cell lymphomas, in which the immunoglobulin (IgH) receptor loci are frequently targeted by chromosomal translocations, the T-cell receptor (TCR) gene loci are affected by translocations in a subset of precursor T-cell malignancies. In a large-scale analysis of 245 paraffin-embedded mature T-NHLs, arranged in a tissue microarray format and using improved FISH assays for the detection of breakpoints in the TCRalpha/delta, TCRbeta, and TCRgamma loci, we provide evidence that mature T-NHLs other than T-cell prolymphocytic leukaemia (T-PLL) also occasionally show a chromosomal rearrangement that involves the TCRalpha/delta locus. In particular, one peripheral T-cell lymphoma (not otherwise specified, NOS) with the morphological variant of Lennert lymphoma displayed a chromosomal translocation t(14;19) involving the TCRalpha/delta and the BCL3 loci. A second case, an angio-immunoblastic T-cell lymphoma (AILT), carried an inv(14)(q11q32) affecting the TCRalpha/delta and IgH loci. FISH signal constellations as well as concomitant comparative genomic hybridization (CGH) data were also suggestive of the occurrence of an isochromosome 7, previously described to be pathognomonic for hepatosplenic T-cell lymphomas, in rare cases of enteropathy-type T-cell lymphoma.
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MESH Headings
- B-Cell Lymphoma 3 Protein
- Case-Control Studies
- Chromosome Breakage
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 19
- Chromosomes, Human, Pair 7
- Gene Expression Profiling
- Gene Rearrangement, T-Lymphocyte
- Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor
- Gene Rearrangement, delta-Chain T-Cell Antigen Receptor
- Genes, T-Cell Receptor
- Humans
- Immunoglobulin Heavy Chains/genetics
- In Situ Hybridization, Fluorescence
- Lymphoma, T-Cell/genetics
- Oligonucleotide Array Sequence Analysis
- Paraffin Embedding
- Proto-Oncogene Proteins/genetics
- Transcription Factors/genetics
- Translocation, Genetic
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68
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Adam P, Schoof J, Hartmann M, Schwarz S, Puppe B, Ott M, Rosenwald A, Ott G, Müller-Hermelink H. Cell migration patterns and ongoing somatic mutations in the progression of follicular lymphoma. Cytogenet Genome Res 2007; 118:328-36. [DOI: 10.1159/000108317] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Accepted: 11/15/2006] [Indexed: 11/19/2022] Open
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69
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Belloni B, Andres C, Ott G, Hein R, Hofmann H, Ring J. [Pfeifer-Weber-Christian syndrome associated with Kikuchi syndrome in infliximab therapy: development of necrotizing allergic vasculitis]. Hautarzt 2007; 58:1018, 1020-1. [PMID: 17994203 DOI: 10.1007/s00105-007-1426-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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70
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Stöcklein H, Smardova J, Macak J, Katzenberger T, Höller S, Wessendorf S, Hutter G, Dreyling M, Haralambieva E, Mäder U, Müller-Hermelink HK, Rosenwald A, Ott G, Kalla J. Detailed mapping of chromosome 17p deletions reveals HIC1 as a novel tumor suppressor gene candidate telomeric to TP53 in diffuse large B-cell lymphoma. Oncogene 2007; 27:2613-25. [PMID: 17982487 DOI: 10.1038/sj.onc.1210901] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Deletions in the short arm of chromosome 17 (17p) involving the tumor suppressor TP53 occur in up to 20% of diffuse large B-cell lymphomas (DLBCLs). Although inactivation of both alleles of a tumor suppressor gene is usually required for tumor development, the overlap between TP53 deletions and mutations is poorly understood in DLBCLs, suggesting the possible existence of additional tumor suppressor genes in 17p. Using a bacterial artificial chromosome (BAC) and Phage 1 artificial chromosome (PAC) contig, we here define a minimally deleted region in DLBCLs encompassing approximately 0.8 MB telomeric to the TP53 locus. This genomic region harbors the tumor suppressor Hypermethylated in Cancer 1 (HIC1). Methylation-specific PCR demonstrated hypermethylation of HIC1 exon 1a in a substantial subset of DLBCLs, which is accompanied by simultaneous HIC1 deletion of the second allele in 90% of cases. In contrast, HIC1 inactivation by hypermethylation was rarely encountered in DLBCLs without concomitant loss of the second allele. DLBCL patients with complete inactivation of both HIC1 and TP53 may be characterized by an even inferior clinical course than patients with inactivation of TP53 alone, suggesting a functional cooperation between these two proteins. These findings strongly imply HIC1 as a novel tumor suppressor in a subset of DLBCLs.
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71
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Ott G, Rosenwald A. [Extranodal diffuse large B-cell lymphoma--an organotypic disease?]. DER PATHOLOGE 2007; 28:29-35. [PMID: 17211671 DOI: 10.1007/s00292-006-0883-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Roughly 30-40% of diffuse large B-cell lymphomas (DLBCL) arise primarily in extranodal sites. Most frequently, they occur in the gastrointestinal tract, especially in the gastric mucosa. They also occur in the central nervous system, as testicular lymphomas, in the lungs, or in the skin. Morphologically, they show the whole spectrum of peripheral B-blasts: centroblasts, immunoblasts, or plasmoblasts. Thus, there is no actual difference in their cytomorphological presentation compared to their nodal-and frequently systemic-counterparts. However, recent data point to profound differences in primary extranodal DLBCL compared to primary nodal tumors, as well as to each other, frequently relating to their molecular characteristics and especially implying organotypic features. These characteristics may relate to a particular organotypic site of origin, or the particular clinico-pathogenetic setting in which the tumors arise. This is exemplified in the description of the DLBCL subtypes as defined by the World Health Organization classification (mediastinal or intravascular B-cell lymphoma; primary effusion lymphoma). On the other hand, primary extranodal DLBCL are frequently characterized by a particular (cyto-)genetic constitution, often related to their site of origin. Finally, some preliminary data on gene expression profiling strongly argue in favor of particular gene signatures for primary extranodal DLBCL, and hence in favor of particular organotypic transformation pathways.
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72
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Adam P, Haralambieva E, Ott G. [Extranodal marginal zone B-cell lymphoma of MALT-type]. DER PATHOLOGE 2007; 28:6-14. [PMID: 17211669 DOI: 10.1007/s00292-006-0887-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Extranodal marginal zone B-cell lymphomas of the MALT type constitute, with around 8% of all B-cell lymphomas, the third most frequent lymphoma in the Western hemisphere. Their unifying characteristic principle is their origin in organs that are typically devoid of a regular lymphatic parenchyma ("primary" MALT). In contrast, "secondary" MALT is acquired in these sites by chronic inflammatory processes triggered by chronic infections or autoimmune diseases. The organotypic characteristics of these particular lymphoid tumours are also mirrored by organ-specific precursor lesions and in tumour biology. Usually, MALT-type lymphomas remain confined to their site of origin for a long time, disseminating only late during the course of the disease. Hence, they may be controlled by local treatment (excision, irradiation). Moreover, the distinctive genetic constitution of MALT-type lymphomas, although varying from organ to organ, indicates particular transformation pathways obviously related to the specific precursor lesion and, hence, of organ-specific quality.
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73
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Iqbal J, Greiner TC, Patel K, Dave BJ, Smith L, Ji J, Wright G, Sanger WG, Pickering DL, Jain S, Horsman DE, Shen Y, Fu K, Weisenburger DD, Hans CP, Campo E, Gascoyne RD, Rosenwald A, Jaffe ES, Delabie J, Rimsza L, Ott G, Müller-Hermelink HK, Connors JM, Vose JM, McKeithan T, Staudt LM, Chan WC. Distinctive patterns of BCL6 molecular alterations and their functional consequences in different subgroups of diffuse large B-cell lymphoma. Leukemia 2007; 21:2332-43. [PMID: 17625604 PMCID: PMC2366166 DOI: 10.1038/sj.leu.2404856] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Gene expression profiling of diffuse large B-cell lymphoma (DLBCL) has revealed biologically and prognostically distinct subgroups: germinal center B-cell-like (GCB), activated B-cell-like (ABC) and primary mediastinal (PM) DLBCL. The BCL6 gene is often translocated and/or mutated in DLBCL. Therefore, we examined the BCL6 molecular alterations in these DLBCL subgroups, and their impact on BCL6 expression and BCL6 target gene repression. BCL6 translocations at the major breakpoint region (MBR) were detected in 25 (18.8%) of 133 DLBCL cases, with a higher frequency in the PM (33%) and ABC (24%) subgroups than in the GCB (10%) subgroup. Translocations at the alternative breakpoint region (ABR) were detected in five (6.4%) of 78 DLBCL cases, with three cases in ABC and one case each in the GCB and the unclassifiable subgroups. The translocated cases involved IgH and non-IgH partners in about equal frequency and were not associated with different levels of BCL6 mRNA and protein expression. BCL6 mutations were detected in 61% of DLBCL cases, with a significantly higher frequency in the GCB and PM subgroups (>70%) than in the ABC subgroup (44%). Exon-1 mutations were mostly observed in the GCB subgroup. The repression of known BCL6 target genes correlated with the level of BCL6 mRNA and protein expression in GCB and ABC subgroups but not with BCL6 translocation and intronic mutations. No clear inverse correlation between BCL6 expression and p53 expression was observed. Patients with higher BCL6 mRNA or protein expression had a significantly better overall survival. The biological role of BCL6 in translocated cases where repression of known target genes is not demonstrated is intriguing and warrants further investigation.
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74
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Grunenberger F, Ott G, Bohbot A, Schlienger JL. Le syndrome de sevrage en hormones thyoïdiennes existe-il? Rev Med Interne 2007. [DOI: 10.1016/j.revmed.2007.03.245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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75
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Ott G, Kaymak H, Mester U. Funktionstraining bei Multifokallinsen. Klin Monbl Augenheilkd 2007. [DOI: 10.1055/s-2007-976255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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