Harder, L. (Lana)

Search Results

Now showing 1 - 6 of 6
  • Thumbnail Image
    Deregulation of the telomerase reverse transcriptase (TERT) gene by chromosomal translocations in B-cell malignancies
    (American Society of Hematology, 2010) Gascoyne, R.D (R. D.); Tönnies, H. (Holger); Ammerpohl, O. (Ole); Dyer, M.J.S. (Martin J. S.); Martinez-Climent, J.A. (José Ángel); Nagel, I. (Inga); Akasaka, T. (T.); Horsman, D. (D.); Gesk, S. (Stefan); Harder, L. (Lana); Klapper, W. (Wolfram); Callet-Bauchu, E. (E.); Siebert, R. (Reiner); Szczepanowski, M. (Monika); Stilgenbauer, S. (Stepahn); Majid, A. (Aneela); Martin-Subero, J.I. (Jose Ignacio)
    Sequence variants at the TERT-CLPTM1L locus in chromosome 5p have been recently associated with disposition for various cancers. Here we show that this locus including the gene encoding the telomerase reverse-transcriptase TERT at 5p13.33 is rarely but recurrently targeted by somatic chromosomal translocations to IGH and non-IG loci in B-cell neoplasms, including acute lymphoblastic leukemia, chronic lymphocytic leukemia, mantle cell lymphoma and splenic marginal zone lymphoma. In addition, cases with genomic amplification of TERT locus were identified. Tumors bearing chromosomal aberrations involving TERT showed higher TERT transcriptional expression and increased telomerase activity. These data suggest that deregulation of TERT gene by chromosomal abnormalities leading to increased telomerase activity might contribute to B-cell lymphomagenesis.
  • Thumbnail Image
    Reseñas Perinola, 16, 2012
    (Servicio de Publicaciones Universidad de Navarra, 2012-04-15) Cappelli, F. (Federica); Arellano-Ayuso, I. (Ignacio); Rey, A. (Alfonso); Harder, L. (Lana)
    Reseñas libros
  • Thumbnail Image
    GeneChip analyses point to novel pathogenetic mechanisms in mantle cell lymphoma
    (Wiley-Blackwell, 2009) Krause, K. (Kristina); Dreyling, M. (Martin); Hasenclever, D. (D.); Kreuz, M. (Markus); Dyer, M.J.S. (Martin J. S.); Berger, H. (H.); Arnold, N. (Norbert); Martinez-Climent, J.A. (José Ángel); Wagner, F. (Florian); Gesk, S. (Stefan); Harder, L. (Lana); Klapper, W. (Wolfram); Zamo, A. (Alberto); Siebert, R. (Reiner); Vater, I. (Inga); Potter, K. (Kathleen N.); Martin-Subero, J.I. (Jose Ignacio)
    The translocation t(11;14)(q13;q32) is the genetic hallmark of mantle cell lymphoma (MCL) but is not sufficient for inducing lymphomagenesis. Here we performed genome-wide 100K GeneChip Mapping in 26 t(11;14)-positive MCL and six MCL cell lines. Partial uniparental disomy (pUPD) was shown to be a recurrent chromosomal event not only in MCL cell lines but also in primary MCL. Remarkably, pUPD affected recurrent targets of deletion like 11q, 13q and 17p. Moreover, we identified 12 novel regions of recurrent gain and loss as well as 12 high-level amplifications and eight homozygously deleted regions hitherto undescribed in MCL. Interestingly, GeneChip analyses identified different genes, encoding proteins involved in microtubule dynamics, such as MAP2, MAP6 and TP53, as targets for chromosomal aberration in MCL. Further investigation, including mutation analyses, fluorescence in situ hybridisation as well as epigenetic and expression studies, revealed additional aberrations frequently affecting these genes. In total, 19 of 20 MCL cases, which were subjected to genetic and epigenetic analyses, and five of six MCL cell lines harboured at least one aberration in MAP2, MAP6 or TP53. These findings provide evidence that alterations of microtubule dynamics might be one of the critical events in MCL lymphomagenesis contributing to chromosomal instability.
  • Thumbnail Image
    A Comprehensive Microarray-Based DNA Methylation Study of 367 Hematological Neoplasms
    (Public Library of Science, 2009) Cigudosa, J.C. (Juan Cruz); Stein, H. (Harald); Ammerpohl, O. (Ole); Dreyling, M. (Martin); Richter, J. (Julia); Trümper, L. (Lorenz); Montesinos-Rongen, M. (Manuel); Roman-Gomez, J. (José); Dyer, M.J.S. (Martin J. S.); Alvarez, S. (Sara); Bug, S. (Stefanie); Dürig, J. (Jan); Nagel, I. (Inga); Seifert, M. (Marc); Gesk, S. (Stefan); Bibikova, M. (Marina); Küppers, R. (Ralf); Harder, L. (Lana); Klapper, W. (Wolfram); Brüggemann, M. (Monika); Siebert, R. (Reiner); Vater, I. (Inga); Haferlach, C. (Claudia); Deckert, M. (Martina); Wickham, E. (Eliza); Du, M.Q. (Ming Q.); Hansmann, M.L. (Martin-Leo); Potter, K. (Kathleen N.); Prosper-Cardoso, F. (Felipe); Fan, J.B. (Jian-Bing); Calasanz-Abinzano, M.J. (Maria Jose); Hartmann, S. (Sylvia); Aguirre-Ena, X. (Xabier); Martin-Subero, J.I. (Jose Ignacio); Suela, J. (Javier)
    Background: Alterations in the DNA methylation pattern are a hallmark of leukemias and lymphomas. However, most epigenetic studies in hematologic neoplasms (HNs) have focused either on the analysis of few candidate genes or many genes and few HN entities, and comprehensive studies are required. Methodology/Principal Findings: Here, we report for the first time a microarray-based DNA methylation study of 767 genes in 367 HNs diagnosed with 16 of the most representative B-cell (n = 203), T-cell (n = 30), and myeloid (n = 134) neoplasias, as well as 37 samples from different cell types of the hematopoietic system. Using appropriate controls of B-, T-, or myeloid cellular origin, we identified a total of 220 genes hypermethylated in at least one HN entity. In general, promoter hypermethylation was more frequent in lymphoid malignancies than in myeloid malignancies, being germinal center mature B-cell lymphomas as well as B and T precursor lymphoid neoplasias those entities with highest frequency of geneassociated DNA hypermethylation. We also observed a significant correlation between the number of hypermethylated and hypomethylated genes in several mature B-cell neoplasias, but not in precursor B- and T-cell leukemias. Most of the genes becoming hypermethylated contained promoters with high CpG content, and a significant fraction of them are targets of the polycomb repressor complex. Interestingly, T-cell prolymphocytic leukemias show low levels of DNA hypermethylation and a comparatively large number of hypomethylated genes, many of them showing an increased gene expression. Conclusions/Significance: We have characterized the DNA methylation profile of a wide range of different HNs entities. As well as identifying genes showing aberrant DNA methylation in certain HN subtypes, we also detected six genes—DBC1, DIO3, FZD9, HS3ST2, MOS, and MYOD1—that were significantly hypermethylated in B-cell, T-cell, and myeloid malignancies. These might therefore play an important role in the development of different HNs.
  • Thumbnail Image
    Chromosomal abnormalities clustering in multiple myeloma reveals cytogenetic subgroups with nonrandom acquisition of chromosomal changes
    (Nature Publishing Group, 2004) Cigudosa, J.C. (Juan Cruz); Guillen-Grima, F. (Francisco); Harder, L. (Lana); Siebert, R. (Reiner); Prosper-Cardoso, F. (Felipe); Calasanz-Abinzano, M.J. (Maria Jose); Odero, M.D. (Maria Dolores); Martin-Subero, J.I. (Jose Ignacio); Saez, B. (Borja)
  • Biallelic inactivation of TRAF3 in a subset of B-cell lymphomas with interstitial del(14)(q24.1q32.33)
    (Nature Publishing Group, 2009) Tönnies, H. (Holger); Ammerpohl, O. (Ole); Richter, J. (Julia); Dyer, M.J.S. (Martin J. S.); Bastard, C. (C.); Bug, S. (Stefanie); Martinez-Climent, J.A. (José Ángel); Nagel, I. (Inga); Gesk, S. (Stefan); Harder, L. (Lana); Callet-Bauchu, E. (E.); Siebert, R. (Reiner); Vater, I. (Inga); Schroers, E. (E.); Calasanz-Abinzano, M.J. (Maria Jose); Salido, M. (Marta); Majid, A. (Aneela); Martin-Subero, J.I. (Jose Ignacio)