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  1. Article ; Online: Development of super-specific epigenome editing by targeted allele-specific DNA methylation.

    Rajaram, Nivethika / Kouroukli, Alexandra G / Bens, Susanne / Bashtrykov, Pavel / Jeltsch, Albert

    Epigenetics & chromatin

    2023  Volume 16, Issue 1, Page(s) 41

    Abstract: Background: Epigenome editing refers to the targeted reprogramming of genomic loci using an EpiEditor which may consist of an sgRNA/dCas9 complex that recruits DNMT3A/3L to the target locus. Methylation of the locus can lead to a modulation of gene ... ...

    Abstract Background: Epigenome editing refers to the targeted reprogramming of genomic loci using an EpiEditor which may consist of an sgRNA/dCas9 complex that recruits DNMT3A/3L to the target locus. Methylation of the locus can lead to a modulation of gene expression. Allele-specific DNA methylation (ASM) refers to the targeted methylation delivery only to one allele of a locus. In the context of diseases caused by a dominant mutation, the selective DNA methylation of the mutant allele could be used to repress its expression but retain the functionality of the normal gene.
    Results: To set up allele-specific targeted DNA methylation, target regions were selected from hypomethylated CGIs bearing a heterozygous SNP in their promoters in the HEK293 cell line. We aimed at delivering maximum DNA methylation with highest allelic specificity in the targeted regions. Placing SNPs in the PAM or seed regions of the sgRNA, we designed 24 different sgRNAs targeting single alleles in 14 different gene loci. We achieved efficient ASM in multiple cases, such as ISG15, MSH6, GPD1L, MRPL52, PDE8A, NARF, DAP3, and GSPT1, which in best cases led to five to tenfold stronger average DNA methylation at the on-target allele and absolute differences in the DNA methylation gain at on- and off-target alleles of > 50%. In general, loci with the allele discriminatory SNP positioned in the PAM region showed higher success rate of ASM and better specificity. Highest DNA methylation was observed on day 3 after transfection followed by a gradual decline. In selected cases, ASM was stable up to 11 days in HEK293 cells and it led up to a 3.6-fold change in allelic expression ratios.
    Conclusions: We successfully delivered ASM at multiple genomic loci with high specificity, efficiency and stability. This form of super-specific epigenome editing could find applications in the treatment of diseases caused by dominant mutations, because it allows silencing of the mutant allele without repression of the expression of the normal allele thereby minimizing potential side-effects of the treatment.
    MeSH term(s) Humans ; DNA Methylation ; RNA, Guide, CRISPR-Cas Systems ; Epigenesis, Genetic ; Alleles ; HEK293 Cells ; Epigenome ; CRISPR-Cas Systems ; Gene Editing
    Chemical Substances RNA, Guide, CRISPR-Cas Systems
    Language English
    Publishing date 2023-10-21
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2462129-8
    ISSN 1756-8935 ; 1756-8935
    ISSN (online) 1756-8935
    ISSN 1756-8935
    DOI 10.1186/s13072-023-00515-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Targeting oncogenic TERT promoter variants by allele-specific epigenome editing.

    Kouroukli, Alexandra G / Rajaram, Nivethika / Bashtrykov, Pavel / Kretzmer, Helene / Siebert, Reiner / Jeltsch, Albert / Bens, Susanne

    Clinical epigenetics

    2023  Volume 15, Issue 1, Page(s) 183

    Abstract: Background: Activation of dominant oncogenes by small or structural genomic alterations is a common driver mechanism in many cancers. Silencing of such dominantly activated oncogenic alleles, thus, is a promising strategy to treat cancer. Recently, ... ...

    Abstract Background: Activation of dominant oncogenes by small or structural genomic alterations is a common driver mechanism in many cancers. Silencing of such dominantly activated oncogenic alleles, thus, is a promising strategy to treat cancer. Recently, allele-specific epigenome editing (ASEE) has been described as a means to reduce transcription of genes in an allele-specific manner. In cancer, specificity to an oncogenic allele can be reached by either targeting directly a pathogenic single-nucleotide variant or a polymorphic single-nucleotide variant linked to the oncogenic allele. To investigate the potential of ASEE in cancer, we here explored this approach by targeting variants at the TERT promoter region. The TERT promoter region has been described as one of the most frequently mutated non-coding cancer drivers.
    Results: Sequencing of the TERT promoter in cancer cell lines showed 53% (41/77) to contain at least one heterozygous sequence variant allowing allele distinction. We chose the hepatoblastoma cell line Hep-G2 and the lung cancer cell line A-549 for this proof-of-principle study, as they contained two different kinds of variants, namely the activating mutation C228T in the TERT core promoter and the common SNP rs2853669 in the THOR region, respectively. These variants were targeted in an allele-specific manner using sgRNA-guided dCas9-DNMT3A-3L complexes. In both cell lines, we successfully introduced DNA methylation specifically to the on-target allele of the TERT promoter with limited background methylation on the off-target allele or an off-target locus (VEGFA), respectively. We observed a maximum CpG methylation gain of 39% and 76% on the target allele when targeting the activating mutation and the common SNP, respectively. The epigenome editing translated into reduced TERT RNA expression in Hep-G2.
    Conclusions: We applied an ASEE-mediated approach to silence TERT allele specifically. Our results show that the concept of dominant oncogene inactivation by allele-specific epigenome editing can be successfully translated into cancer models. This new strategy may have important advantages in comparison with existing therapeutic approaches, e.g., targeting telomerase, especially with regard to reducing adverse side effects.
    MeSH term(s) Humans ; Alleles ; DNA Methylation ; Epigenome ; RNA, Guide, CRISPR-Cas Systems ; Promoter Regions, Genetic ; Lung Neoplasms ; Nucleotides ; Mutation ; Telomerase/genetics
    Chemical Substances RNA, Guide, CRISPR-Cas Systems ; Nucleotides ; TERT protein, human (EC 2.7.7.49) ; Telomerase (EC 2.7.7.49)
    Language English
    Publishing date 2023-11-22
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553921-8
    ISSN 1868-7083 ; 1868-7075
    ISSN (online) 1868-7083
    ISSN 1868-7075
    DOI 10.1186/s13148-023-01599-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: PI3K/AKT inhibitor BEZ-235 targets CCND2 and induces G1 arrest in breast implant-associated anaplastic large cell lymphoma.

    Nagel, Stefan / Fischer, Anja / Bens, Susanne / Hauer, Vivien / Pommerenke, Claudia / Uphoff, Cord C / Zaborski, Margarete / Siebert, Reiner / Quentmeier, Hilmar

    Leukemia research

    2023  Volume 133, Page(s) 107377

    Abstract: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a mature, CD30-positive T-cell lymphoma lacking expression of the anaplastic lymphoma kinase (ALK). In contrast to ALK-positive ALCL, BIA-ALCL cells express cyclin D2 (CCND2) which ... ...

    Abstract Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a mature, CD30-positive T-cell lymphoma lacking expression of the anaplastic lymphoma kinase (ALK). In contrast to ALK-positive ALCL, BIA-ALCL cells express cyclin D2 (CCND2) which controls cyclin dependent kinases 4 and 6 (CDK4/6). DNA methylation and expression analyses performed with cell lines and primary cells suggest that the expression of CCND2 in BIA-ALCL cell lines conforms to the physiological status of differentiated T-cells, and that it is not the consequence of genomic alterations as observed in other hematopoietic tumors. Using cell line model systems we show that treatment with the CDK4/6 inhibitor palbociclib effects dephosphorylation of the retinoblastoma protein (RB) and causes cell cycle arrest in G1 in BIA-ALCL. Moreover, we show that the PI3K/AKT inhibitor BEZ-235 induces dephosphorylation of the mTORC1 target S6 and of GSK3β, indicators for translational inhibition and proteasomal degradation. Consequently, CCND2 protein levels declined after stimulation with BEZ-235, RB was dephosphorylated and the cell cycle was arrested in G1. Taken together, our data imply potential application of CDK4/6 inhibitors and PI3K/AKT inhibitors for the therapy of BIA-ALCL.
    Language English
    Publishing date 2023-08-27
    Publishing country England
    Document type Journal Article
    ZDB-ID 752396-8
    ISSN 1873-5835 ; 0145-2126
    ISSN (online) 1873-5835
    ISSN 0145-2126
    DOI 10.1016/j.leukres.2023.107377
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Successful Retreatment With Venetoclax in a Patient With Chronic Lymphocytic Leukemia.

    Jackson, Ross A / Smith, Victoria M / Jayne, Sandrine / Drewes, Cosima / Bens, Susanne / Siebert, Reiner / Dyer, Martin J S / Walter, Harriet S

    HemaSphere

    2022  Volume 6, Issue 8, Page(s) e752

    Language English
    Publishing date 2022-07-15
    Publishing country United States
    Document type Journal Article
    ISSN 2572-9241
    ISSN (online) 2572-9241
    DOI 10.1097/HS9.0000000000000752
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Book ; Online ; Thesis: Serumcortisol-Kurzprofil bei Patientinnen mit Borderline-Persönlichkeitsstörung

    Bens, Susanne

    2005  

    Author's details vorgelegt von Susanne Bens
    Language German
    Size Online-Ressource
    Document type Book ; Online ; Thesis
    Thesis / German Habilitation thesis Univ., Diss--Lübeck, 2005
    Database Former special subject collection: coastal and deep sea fishing

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  6. Article ; Online: The DNA methylation status of the TERT promoter differs between subtypes of mature B-cell lymphomas.

    Kouroukli, Alexandra G / Fischer, Anja / Kretzmer, Helene / Chteinberg, Emil / Rajaram, Nivethika / Glaser, Selina / Kolarova, Julia / Bashtrykov, Pavel / Mathas, Stephan / Drexler, Hans G / Ohno, Hitoshi / Ammerpohl, Ole / Jeltsch, Albert / Siebert, Reiner / Bens, Susanne

    Blood cancer journal

    2023  Volume 13, Issue 1, Page(s) 98

    MeSH term(s) Humans ; DNA Methylation ; Lymphoma, B-Cell/genetics ; CpG Islands ; Telomerase/genetics ; Telomerase/metabolism
    Chemical Substances TERT protein, human (EC 2.7.7.49) ; Telomerase (EC 2.7.7.49)
    Language English
    Publishing date 2023-06-26
    Publishing country United States
    Document type Letter ; Research Support, Non-U.S. Gov't
    ZDB-ID 2600560-8
    ISSN 2044-5385 ; 2044-5385
    ISSN (online) 2044-5385
    ISSN 2044-5385
    DOI 10.1038/s41408-023-00872-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Desmoplastic myxoid tumor of pineal region, SMARCB1-mutant, in young adult.

    Manoranjan, Branavan / Starreveld, Yves P / Nordal, Robert A / Dunham, Christopher / Bens, Susanne / Thomas, Christian / Hasselblatt, Martin / Joseph, Jeffrey T

    Free neuropathology

    2021  Volume 2

    Abstract: We present a young adult woman who developed a myxoid tumor of the pineal region having ... ...

    Abstract We present a young adult woman who developed a myxoid tumor of the pineal region having a
    Language English
    Publishing date 2021-06-01
    Publishing country Germany
    Document type Journal Article
    ISSN 2699-4445
    ISSN (online) 2699-4445
    DOI 10.17879/freeneuropathology-2021-3340
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Double-hit lymphoma of the male breast: a case report.

    Elgaafary, Shaymaa / Nagel, Inga / López, Cristina / Bens, Susanne / Szczepanowski, Monika / Wagener, Rabea / Klapper, Wolfram / Siebert, Reiner

    Journal of medical case reports

    2020  Volume 14, Issue 1, Page(s) 245

    Abstract: Background: Whereas lymphoma of the female breast is already rare, lymphoma of the male breast has only anecdotally been reported. Within a study of 32 lymphoma of the breast reported between 1973 and 2014 as Burkitt lymphoma, we observed a single male ... ...

    Abstract Background: Whereas lymphoma of the female breast is already rare, lymphoma of the male breast has only anecdotally been reported. Within a study of 32 lymphoma of the breast reported between 1973 and 2014 as Burkitt lymphoma, we observed a single male case, which we report here.
    Case presentation: A 72-years-old Caucasian man presented with a mass in his left breast. Clinical history included prior basal cell carcinoma, leiomyosarcoma, and administration of spironolactone. The reference pathology diagnosis at presentation was Burkitt lymphoma according to the Kiel Classification. The present re-investigation using fluorescence in situ hybridization revealed an IGH-MYC translocation and a break in the BCL2 locus in the tumor cells. Thus, in light of the current WHO classification, the diagnosis was revised to high-grade B-cell lymphoma with MYC and BCL2 rearrangement, Burkitt morphology (so-called "double-hit" lymphoma). Genome-wide chromosomal imbalance mapping revealed a complex pattern of aberrations in line with this diagnosis. The aberrations, including copy-number gains in chromosomes 3q and 18 and focal homozygous loss in 9p21.3, resembled typical changes of lymphomas affecting "immune-privileged" sites.
    Conclusion: The present case adds to the understanding of the pathogenesis of male breast lymphomas, about which hardly any molecular characterization has been published yet.
    MeSH term(s) Aged ; Burkitt Lymphoma/diagnosis ; Burkitt Lymphoma/drug therapy ; Burkitt Lymphoma/genetics ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Lymphoma, B-Cell/diagnosis ; Lymphoma, B-Cell/genetics ; Male ; Proto-Oncogene Proteins c-bcl-2/genetics ; Proto-Oncogene Proteins c-myc/genetics ; Translocation, Genetic
    Chemical Substances Proto-Oncogene Proteins c-bcl-2 ; Proto-Oncogene Proteins c-myc
    Language English
    Publishing date 2020-12-18
    Publishing country England
    Document type Case Reports ; Journal Article
    ZDB-ID 2269805-X
    ISSN 1752-1947 ; 1752-1947
    ISSN (online) 1752-1947
    ISSN 1752-1947
    DOI 10.1186/s13256-020-02526-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Transposable element insertion as a mechanism of SMARCB1 inactivation in atypical teratoid/rhabdoid tumor.

    Thomas, Christian / Oehl-Huber, Kathrin / Bens, Susanne / Soschinski, Patrick / Koch, Arend / Nemes, Karolina / Oyen, Florian / Kordes, Uwe / Kool, Marcel / Frühwald, Michael C / Hasselblatt, Martin / Siebert, Reiner

    Genes, chromosomes & cancer

    2021  Volume 60, Issue 8, Page(s) 586–590

    Abstract: Atypical teratoid/rhabdoid tumor (AT/RT) is a malignant brain tumor predominantly occurring in infants. Biallelic SMARCB1 mutations causing loss of nuclear SMARCB1/INI1 protein expression represent the characteristic genetic lesion. Pathogenic SMARCB1 ... ...

    Abstract Atypical teratoid/rhabdoid tumor (AT/RT) is a malignant brain tumor predominantly occurring in infants. Biallelic SMARCB1 mutations causing loss of nuclear SMARCB1/INI1 protein expression represent the characteristic genetic lesion. Pathogenic SMARCB1 mutations comprise single nucleotide variants, small insertions/deletions, large deletions, which may be also present in the germline (rhabdoid tumor predisposition syndrome 1), as well as somatic copy-number neutral loss of heterozygosity (LOH). In some SMARCB1-deficient AT/RT underlying biallelic mutations cannot be identified. Here we report the case of a 24-months-old girl diagnosed with a large brain tumor. The malignant rhabdoid tumor showed loss of nuclear SMARCB1/INI1 protein expression and the diagnosis of AT/RT was confirmed by DNA methylation profiling. While FISH, MLPA, Sanger sequencing and DNA methylation data-based imbalance analysis did not disclose alterations affecting SMARCB1, OncoScan array analysis revealed a 28.29 Mb sized region of copy-number neutral LOH on chromosome 22q involving the SMARCB1 locus. Targeted next-generation sequencing did also not detect a single nucleotide variant but instead revealed insertion of an AluY element into exon 2 of SMARCB1. Specific PCR-based Sanger sequencing verified the Alu insertion (SMARCB1 c.199_200 Alu ins) resulting in a frame-shift truncation not present in the patient's germline. In conclusion, transposable element insertion represents a hitherto not widely recognized mechanism of SMARCB1 disruption in AT/RT, which might not be detected by several widely applied conventional diagnostics assays. This finding has particular clinical implications, if rhabdoid predisposition syndrome 1 is suspected, but germline SMARCB1 alterations cannot be identified.
    MeSH term(s) Brain Neoplasms/genetics ; Brain Neoplasms/pathology ; DNA Transposable Elements ; Female ; Humans ; Infant ; Mutagenesis, Insertional ; Rhabdoid Tumor/genetics ; Rhabdoid Tumor/pathology ; SMARCB1 Protein/genetics ; Teratoma/genetics ; Teratoma/pathology
    Chemical Substances DNA Transposable Elements ; SMARCB1 Protein ; SMARCB1 protein, human
    Language English
    Publishing date 2021-05-08
    Publishing country United States
    Document type Case Reports ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1018988-9
    ISSN 1098-2264 ; 1045-2257
    ISSN (online) 1098-2264
    ISSN 1045-2257
    DOI 10.1002/gcc.22954
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Recurrent atypical teratoid/rhabdoid tumors (AT/RT) reveal discrete features of progression on histology, epigenetics, copy number profiling, and transcriptomics.

    Johann, Pascal D / Altendorf, Lea / Efremova, Emma-Maria / Holsten, Till / Steinbügl, Mona / Nemes, Karolina / Eckhardt, Alicia / Kresbach, Catena / Bockmayr, Michael / Koch, Arend / Haberler, Christine / Antonelli, Manila / DeSisto, John / Schuhmann, Martin U / Hauser, Peter / Siebert, Reiner / Bens, Susanne / Kool, Marcel / Green, Adam L /
    Hasselblatt, Martin / Frühwald, Michael C / Schüller, Ulrich

    Acta neuropathologica

    2023  Volume 146, Issue 3, Page(s) 527–541

    Abstract: Atypical teratoid/rhabdoid tumors (AT/RT) are the most common malignant brain tumors manifesting in infancy. They split into four molecular types. The major three (AT/RT-SHH, AT/RT-TYR, and AT/RT-MYC) all carry mutations in SMARCB1, the fourth ... ...

    Abstract Atypical teratoid/rhabdoid tumors (AT/RT) are the most common malignant brain tumors manifesting in infancy. They split into four molecular types. The major three (AT/RT-SHH, AT/RT-TYR, and AT/RT-MYC) all carry mutations in SMARCB1, the fourth quantitatively smaller type is characterized by SMARCA4 mutations (AT/RT-SMARCA4). Molecular characteristics of disease recurrence or metastatic spread, which go along with a particularly dismal outcome, are currently unclear. Here, we investigated tumor tissue from 26 patients affected by AT/RT to identify signatures of recurrences in comparison with matched primary tumor samples. Microscopically, AT/RT recurrences demonstrated a loss of architecture and significantly enhanced mitotic activity as compared to their related primary tumors. Based on DNA methylation profiling, primary tumor and related recurrence were grossly similar, but three out of 26 tumors belonged to a different molecular type or subtype after second surgery compared to related primary lesions. Copy number variations (CNVs) differed in six cases, showing novel gains on chromosome 1q or losses of chromosome 10 in recurrences as the most frequent alterations. To consolidate these observations, our cohort was combined with a data set of unmatched primary and recurrent AT/RT, which demonstrated chromosome 1q gain and 10 loss in 18% (n = 7) and 11% (n = 4) of the recurrences (n = 38) as compared to 7% (n = 3) and 0% (n = 0) in the primary tumors (n = 44), respectively. Similar to the observations made by DNA methylation profiling, RNA sequencing of our cohort revealed AT/RT primary tumors and matched recurrences clustering closely together. However, a number of genes showed significantly altered expression in AT/RT-SHH recurrences. Many of them are known tumor driving growth factors, involved in embryonal development and tumorigenesis, or are cell-cycle-associated. Overall, our work identifies subtle molecular changes that occur in the course of the disease and that may help define novel therapeutic targets for AT/RT recurrences.
    MeSH term(s) Child ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Chromosomes, Human, Pair 1/genetics ; Chromosomes, Human, Pair 10/genetics ; Cohort Studies ; Dendritic Cells ; Disease Progression ; DNA Copy Number Variations/genetics ; DNA Methylation ; Epigenesis, Genetic ; Gene Expression Profiling ; Histology ; Mitosis ; Recurrence ; Rhabdoid Tumor/classification ; Rhabdoid Tumor/genetics ; Rhabdoid Tumor/immunology ; Rhabdoid Tumor/pathology ; Sequence Analysis, RNA ; Teratoma/classification ; Teratoma/genetics ; Teratoma/immunology ; Teratoma/pathology ; Transcription Factors/genetics ; Gene Expression Regulation, Neoplastic/genetics
    Chemical Substances Transcription Factors ; SMARCA4 protein, human (EC 3.6.1.-) ; SMARCB1 protein, human
    Language English
    Publishing date 2023-07-14
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1079-0
    ISSN 1432-0533 ; 0001-6322
    ISSN (online) 1432-0533
    ISSN 0001-6322
    DOI 10.1007/s00401-023-02608-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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