GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    In: Blood, American Society of Hematology, Vol. 125, No. 13 ( 2015-03-26), p. 2101-2110
    Abstract: LMP1 expression in post germinal center B cells results in downregulation of shelterin proteins, telomeric aggregates, and multinuclearity. LMP1 targets TRF1, TRF2, and POT1 reversibly at the transcriptional/translational level, and TRF2 is essential to block multinuclearity.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2015
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: BMC Cell Biology, Springer Science and Business Media LLC, Vol. 11, No. 1 ( 2010-12)
    Type of Medium: Online Resource
    ISSN: 1471-2121
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2010
    detail.hit.zdb_id: 2964981-X
    detail.hit.zdb_id: 2041486-9
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Online Resource
    Online Resource
    American Society of Hematology ; 2010
    In:  Blood Vol. 116, No. 21 ( 2010-11-19), p. 745-745
    In: Blood, American Society of Hematology, Vol. 116, No. 21 ( 2010-11-19), p. 745-745
    Abstract: Abstract 745 Introduction: Innovative 3D telomere q-FISH allows a mechanistic understanding of the transition from the mononuclear Hodgkin (H) to the multinuclear Reed-Sternberg (RS) cell in in Hodgkin's lymphoma (HL) derived cell lines and diagnostic patient biopsies (Leukemia. 2009; 23:565-573). In RS-cells the telomere protecting shelterin complex appears to be disrupted and deregulation of DNA repair mechanisms is observed. These changes occur in both, classical EBV negative and EBV-associated, LMP1 expressing HL (Lab Invest. 2010; 90:611-619). However, it is not known whether the 3D telomere profile at diagnostic biopsy is different in patients entering rapid remission after initiation of standard chemotherapy (ABVD) compared to that-one of patients with relapsing or refractory disease. In order to answer this question we analyzed by 3D telomere q-FISH diagnostic biopsies of HL patients entering rapid complete remission and compared them to diagnostic biopsies of patients with relapsing or refractory disease. Patients and methods: Rapid remission group (after 1–4 cycles of ABVD): 7 diagnostic biopsies of 7 patients, 19–57 years old, 5 male, 3 LMP1 expressing, 4 nodular sclerosis subtype, 3 mixed cellularity subtype, stages IA, IIA, IIIA × 2, IIIB x2, IVA. Relapse group: 7 diagnostic biopsies of 4 patients, 40–77 years old, 2 male, 1 LMP1 expressing, 3 nodular sclerosis subtype, 1 mixed cellularity subtype, stages IIA bulky, IIIB × 2, IVB; first remission after 6–8 cycles of ABVD in 3 patients, 1 patient died from progressive disease after 11 months. 3D telomere q-FISH was performed as described (Lab Invest. 2010; 90:611-619) and statistical analysis was performed using nested or two-way analysis of variance. Results: Bi- or multinuclear RS-cells of all patients from both groups showed a significant increase of very short telomeres and telomere aggregates when compared to the mononuclear precursor H-cells. However, most importantly, all diagnostic biopsies of the relapse group contained a very high percentage of very small telomeres, including so-called “t-stumps”, in both, H-cells (76,8 ± 11,8%) and RS-cells (87,9 ± 7,3%). Compared to the percentage of very small telomeres identified in both, H-cells (33,7 ± 9,4%) and RS-cells (54,6 ± 15,0%) of the rapid remission group, this increase is highly significant (p 〈 0.001). Moreover, analogous findings are observed for the number of telomere aggregates. In the relapse group the average numbers of telomere aggregates per cell were 4,3 ± 2,4 aggregates per H-cell and 5,4 ± 3.0 aggregates per RS-cell, compared to 1,2 ± 0,7 aggregates per H-cell and 3,3 ± 1,1 aggregates per RS-cell in the rapid remission group. Discussion: The 3D nuclear telomere organization of H- and RS- cells in diagnostic biopsies of relapsing or refractory HL is characterized by both, H- and RS-cells with abundant “t-stumps” and numerous telomere aggregates. Very short telomeres, including t-stumps, and telomere aggregates, both, are characteristics of aggressiveness in cancer biology (Mol Cell. 2007;28:315-327; J Cell Biochem. 2010; 109:1095-1102). Thus, H- and RS-cells of refractory or relapsing HL show significant differences in the 3D telomere dynamics already at first, diagnostic biopsy when compared to H- and RS-cells of HL entering rapid remissions. Disclosures: No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2010
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    In: Blood, American Society of Hematology, Vol. 116, No. 21 ( 2010-11-19), p. 3625-3625
    Abstract: Abstract 3625 Introduction: Tumour cells in classical Hodgkin's lymphoma (HL) and Burkitt's lymphoma (BL) are derived from germinal center B-cells and may or may not harbour the EBV genome. In both, EBV-negative and EBV-associated HL, the 3D nuclear organization of telomeres marks the transition from mononuclear Hodgkin (H-cell) to diagnostic multinuclear Reed-Sternberg (RS-cell) cells. Moreover, transient expression of the EBV-encoded oncoprotein LMP1 in the HL cell lines L-428 and HD-MyZ significantly increases the percentage of RS cells. However, the molecular mechanisms through which this selective LMP1 oncoprotein expression promotes the transition from H- to RS-cells is still unknown. In order to answer this question we analyzed the 3D telomere dynamics and the expression of key shelterin proteins at the transcriptional, translational and topographical localization level in the EBV-negative Burkitt cell line BJAB, stably transfected with an inducible LMP1 system (tetracycline on/off system). To mimic the permanent LMP1 expression as observed in tumour cells of EBV-associated Hodgkin's lymphoma, we extended the period of LMP1 expression up to 21 days and examined key proteins of the shelterin complex, 3D telomere dynamics and formation of multinuclear cells in interphase nuclei of BJAB Burkitt's lymphoma cells at day 1, 3, 7, 10, 14 and 21. Statistical analysis was performed using nested or two-way analysis of variance. Results: Already at day 3 LMP1 induced substantial down regulation of the shelterin key-components TRF1, TRF2 and POT1 at the transcriptional and protein level. This down regulation was reversible after LMP1 suppression; in particular, suppression of LMP1 induction at day 7 returned shelterin-key components to the initial level of expression at day 14. Massive LMP1 mediated down regulation of shelterin proteins was also confirmed by immunofluorescence. At day 7, stable LMP1 expression led to a significant increase of 3D telomere aggregates, nuclear volume and polyploid cells, most of them multinucleated, when compared to non-LMP1 expressing BJAB controls (p 〈 0.02). These changes progressed over time and at day 21 LMP1 expressing BJAB cells were characterized by highly significant increase of 3D telomere aggregates (p = 0.0005) and increased nuclear volume (p 〈 0.0001), compared to the LMP1-suppressed control. Discussion: In an experimental setting mimicking the in vivo conditions of EBV-associated HL, i.e. a permanent LMP1 expression in the H-cells, the LMP1 oncoprotein deregulates shelterin-expression, leads to telomere aggregates and mediates multinuclearity. Our findings point to a shelterin/telomere related key function of LMP1 in Reed-Sternberg cell formation in EBV-associated Hodgkin's lymphoma and may explain the four fold increased risk to develop HL within a median incubation time of four years after symptomatic EBV infection. The LMP1-dependent mechanisms involved are probably unprotected telomeres (shelterin down regulation) favouring chromosomal rearrangements as a result of telomeric aggregate formation and ongoing bridge-fusion- bridge cycles which lead to disturbed cytokinesis and finally multinuclearity. Disclosures: No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2010
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    In: Translational Oncology, Elsevier BV, Vol. 5, No. 4 ( 2012-08), p. 269-277
    Type of Medium: Online Resource
    ISSN: 1936-5233
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2012
    detail.hit.zdb_id: 2443840-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    In: Laboratory Investigation, Elsevier BV, Vol. 90, No. 4 ( 2010-04), p. 611-619
    Type of Medium: Online Resource
    ISSN: 0023-6837
    RVK:
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2010
    detail.hit.zdb_id: 2041329-4
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...