Doerte Siemer

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Primary lymphomas of the CNS (PCNSLs) show molecular features of the late germinal center exit B-cell phenotype and are impaired in their terminal differentiation as indicated by a lack of immunoglobulin class switching. Because the positive regulatory domain I protein with ZNF domain (PRDM1/BLIMP1) is a master regulator of terminal B-cell differentiation(More)
EBV-associated Hodgkin lymphoma (HL) and some post-transplant lymphoproliferative disease (PTLD) cases originate from pro-apoptotic germinal center (GC) B cells that have acquired destructive somatic Ig V gene mutations and were presumably rescued from apoptosis by EBV. To find out whether B cell receptor-crippled GC B cells acquire features of HL and/or(More)
PURPOSE B-cell chronic lymphocytic leukemia (B-CLL) is characterized by the accumulation of monoclonal mature B cells. The G protein Galphas subunit has been linked to proapoptotic processes in cancer cell lines. The TT genotype of the GNAS1 T393C polymorphism is associated with increased Galphas transcript levels and a more favorable clinical course in(More)
Recent studies point to a role of nuclear factor (NF)-kappaB signaling in a subset of diffuse large B cell lymphomas. We have analyzed the expression of 21 genes encoding NF-kappaB family members, upstream modulators, and targets in 32 primary central nervous system lymphomas (PCNSLs) by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).(More)
Alterations in the function of the p53 pathway are frequently described in chronic lymphocytic leukemia (CLL), mostly associated with deletion of 17p13 and/or mutations of the TP53 gene. In the present study, we investigated 103 CLLs for the impact of protein expression of full-length p53 and its isoforms β and γ. A strong correlation between deletions of(More)
The occurrence of trisomy 19 was investigated in 705 cases of B-chronic lymphocytic leukaemia (CLL) by metaphase cytogenetic and/or fluorescence in situ hybridisation analyses. Trisomy 19 was detected in 11 cases (1.6%), all of which also carried a trisomy 12; nine of 10 had mutated IGHV genes. In contrast, B-CLL cases with trisomy 12 lacking trisomy 19(More)
In the present study, telomere length, telomerase activity, the mutation load of immunoglobulin variable heavy chain (IGHV) genes, and established prognostic factors were investigated in 78 patients with chronic lymphocytic leukaemia (CLL) to determine the impact of telomere biology on the pathogenesis of CLL. Telomere length was measured by an automated(More)
Forkhead box P1 (FOXP1) protein is a transcription factor involved in cell signaling and regulation of gene expression. The overexpression of FOXP1 in a subgroup of systemic diffuse large B-cell lymphomas has been associated with an exceptionally poor clinical outcome. Data on FOXP1 expression in primary central nervous system lymphomas (PCNSL), that is,(More)
Up to 40% of Hodgkin lymphoma (HL) cases are associated with the Epstein-Barr virus (EBV). Clonal viral genomes can be found in the HL tumor cells, the Hodgkin Reed-Sternberg cells (HRS). The latent infection results in expression of the viral oncogenes LMP1 and LMP2A which contribute to generate the particular phenotype of the HRS cells. EBV does not only(More)
It is controversially discussed whether human IgM(+)IgD(+)CD27(+) B cells, which carry somatically mutated Ig variable region (IgV) genes, are derived from germinal centres (GC) B cells or originate from another developmental pathway. GC composed of IgM(+)IgD(+) B cells, which co-express the CD70 surface marker, have been described in approximately 10% of(More)
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