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Diagnostics (Basel, Switzerland), 8
2018

Aneuploid CTC and CEC.

Lin, Peter Ping

Conventional circulating tumor cell (CTC) detection technologies are restricted to large tumor cells (> white blood cells (WBCs)), or those unique carcinoma cells with double positive expression of surface epithelial cell adhesion molecule (EpCAM) for isolation, and intracellular structural protein cytokeratins (CKs) for identification. With respect to detecting the full spectrum of highly heterogeneous circulating rare cells (CRCs), including CTCs and circulating endothelial cells (CECs), it is imperative to develop a strategy systematically coordinating all tri-elements of nucleic acids, biomarker proteins, and cellular morphology, to effectively enrich and comprehensively identify CRCs. Accordingly, a novel strategy integrating subtraction enrichment and immunostaining-fluorescence in situ hybridization (SE-iFISH), independent of cell size variation and free of hypotonic damage as well as anti-EpCAM perturbing, has been demonstrated to enable in situ phenotyping multi-protein expression, karyotyping chromosome aneuploidy, and detecting cytogenetic rearrangements of the gene in non-hematologic CRCs. Symbolic non-synonymous single nucleotide variants (SNVs) of both the gene (P33R) in each single aneuploid CTCs, and the cyclin-dependent kinase inhibitor 2A ( ) tumor suppressor gene in each examined aneuploid CECs, were identified for the first time across patients with diverse carcinomas. Comprehensive co-detecting observable aneuploid CTCs and CECs by SE-iFISH, along with applicable genomic and/or proteomic single cell molecular profiling, are anticipated to facilitate elucidating how those disparate categories of aneuploid CTCs and CECs cross-talk and functionally interplay with tumor angiogenesis, therapeutic drug resistance, tumor progression, and cancer metastasis.

Digital object identifier (DOI): 10.3390/diagnostics8020026

Pathology, research and practice, 214, 318--324
2018

Osteosarcoma arising in fibrous dysplasia, confirmed by mutational analysis of GNAS gene.

Sugiura, Yoshiya, Kanda, Hiroaki, Motoi, Noriko, Nomura, Kimie, Inamura, Kentaro, Okada, Erina, Matsumoto, Haruna, Shimoji, Takashi, Matsumoto, Seiichi, Nakayama, Jun, Takazawa, Yutaka, Ishikawa, Yuichi, Machinami, Rikuo

Malignancy arising in fibrous dysplasia (FD) is rare. Approximately 100 cases have been reported so far, and osteosarcoma is the most common malignancy. We report a case of osteosarcoma in a 33-year-old Japanese man with monostotic FD of the right proximal femur from the age of 16 years. Histologically, relatively well-differentiated osteosarcoma was found in the FD lesion. Immunohistochemically, the FD was negative for p53 or MDM2, and the MIB-1 index was less than 1%, whereas the osteosarcoma was positive for both p53 and MDM2, and the MIB-1 index was up to 15%. The FD and osteosarcoma were negative for CDK4. Fluorescent in situ hybridization assay showed no amplification of the MDM2 gene, indicating that the osteosarcoma was a conventional osteosarcoma, not an intraosseous well-differentiated type. The original cell of malignancy in FD is unclear. Malignancy can be potentially derived from dysplastic cells in the area of the FD or cells in the adjacent normal tissues. GNAS gene mutation has recently been reported for fibrous dysplasia and the mutation is highly specific to fibrous dysplasia among fibro-osseous lesions including osteosarcoma. In this case, point mutations of GNAS were found in the FD and osteosarcoma but not in the adjacent normal tissues, suggesting that osteosarcoma was derived from the spindle cells of FD. This is the first report to clearly show that osteosarcoma is derived from the spindle cells in fibrous dysplasia (FD).

Digital object identifier (DOI): 10.1016/j.prp.2017.10.018

Cancer letters, 412, 99--107
2018

Quantified postsurgical small cell size CTCs and EpCAM, [email protected], circulating tumor stem cells with cytogenetic abnormalities in hepatocellular carcinoma patients determine cancer relapse.

Wang, Liang, Li, Yilin, Xu, Jing, Zhang, Aiqun, Wang, Xuedong, Tang, Rui, Zhang, Xinjing, Yin, Hongfang, Liu, Manting, Wang, Daisy Dandan, Lin, Peter Ping, Shen, Lin, Dong, Jiahong

Detection of hepatocellular carcinoma circulating tumor cells performed with conventional strategies, is significantly limited due to inherently heterogeneous and dynamic expression of EpCAM, as well as degradation of cytokeratins during epithelial-to-mesenchymal transition, which inevitably lead to non-negligible false negative detection of such "uncapturable and invisible" CTCs. A novel SE-iFISH strategy, improved for detection of HCC CTCs in this study, was applied to comprehensively detect, in situ phenotypically and karyotypically characterize hepatocellular and cholangiocarcinoma CTCs (CD45 /CD31 ) in patients subjected to surgical resection. Clinical significance of diverse subtypes of CTC was systematically investigated. Existence of small cell size CTCs (≤5 μm of WBCs) with cytogenetic abnormality of aneuploid chromosome 8, which constituted majority of the detected CTCs in HCC patients, was demonstrated for the first time. The stemness marker EpCAM aneuploid circulating tumor stem cells (CTSCs), and EpCAM small CTCs with trisomy 8, promote tumor growth. Postsurgical quantity of small triploid CTCs (≥5 cells/6 ml blood), multiploid (≥pentasomy 8) CTSCs or CTM (either one ≥ 1) significantly correlated to HCC patients' poor prognosis, indicating that detection of those specific subtypes of CTCs and CTSCs in post-operative patients help predict neoplasm recurrence.

Digital object identifier (DOI): 10.1016/j.canlet.2017.10.004

The American journal of surgical pathology, 42, 656--664
2018

Clarifying the Distinction Between Malignant Peripheral Nerve Sheath Tumor and Dedifferentiated Liposarcoma: A Critical Reappraisal of the Diagnostic Utility of MDM2 and H3K27me3 Status.

Makise, Naohiro, Sekimizu, Masaya, Kubo, Takashi, Wakai, Susumu, Hiraoka, Nobuyoshi, Komiyama, Motokiyo, Fukayama, Masashi, Kawai, Akira, Ichikawa, Hitoshi, Yoshida, Akihiko

Malignant peripheral nerve sheath tumor (MPNST) and dedifferentiated liposarcoma (DDLPS) are 2 major types of pleomorphic spindle cell sarcoma. The differentiation of MPNST and DDLPS by histomorphology alone can be problematic. Although MDM2 amplification and PRC2 alteration leading to H3K27me3 deficiency are genetic hallmarks of DDLPS and MPNST, respectively, a small number of MDM2-amplified MPNSTs and H3K27me3-deficient DDLPSs have been reported in the literature. We systematically compared MDM2 and H3K27me3 status in 68 MPNSTs and 47 DDLPSs. Of the 62 MPNSTs, 22 were immunopositive for MDM2, mostly in a weak and/or focal manner. Of the 21 MDM2-positive MPNSTs successfully tested by fluorescence in situ hybridization, high-level MDM2 amplification was observed in 1 case. In contrast, MDM2 staining and high-level MDM2 amplification were positive in all the DDLPS tested (28/28 and 20/20). Of the 68 MPNSTs, 42 cases (62%) exhibited complete loss of H3K27me3. All the 13 MPNSTs that showed heterologous differentiation were deficient in H3K27me3. Of the 47 DDLPSs, 3 cases (6%) had complete loss of H3K27me3, all of which exhibited heterologous differentiation. One case of H3K27me3-deficient DDLPS exhibited homozygous loss of EED according to targeted next-generation sequencing, whereas there were no alterations in NF1 and CDKN2A. In conclusion, high-level MDM2 amplification strongly suggests DDLPS over MPNST. Although a good marker for MPNST, H3K27me3 deficiency also uncommonly occurs in DDLPS in association with PRC2 mutational inactivation. Because both markers are imperfectly specific, rare sarcomas with dual features could be encountered, and their classification should integrate other parameters.

Digital object identifier (DOI): 10.1097/PAS.0000000000001014

Cancer genomics & proteomics, 15, 91--114
2018

Characterization of Camptothecin-induced Genomic Changes in the Camptothecin-resistant T-ALL-derived Cell Line CPT-K5.

Kjeldsen, Eigil, Nielsen, Christine J F, Roy, Amit, Tesauro, Cinzia, Jakobsen, Ann-Katrine, Stougaard, Magnus, Knudsen, Birgitta R

Acquisition of resistance to topoisomerase I (TOP1)-targeting camptothecin (CPT) derivatives is a major clinical problem. Little is known about the underlying chromosomal and genomic mechanisms. We characterized the CPT-K5 cell line expressing mutant CPT-resistant TOP1 and its parental T-cell derived acute lymphoblastic leukemia CPT-sensitive RPMI-8402 cell line by karyotyping and molecular genetic methods, including subtractive oligo-based array comparative genomic hybridization (soaCGH) analysis. Karyotyping revealed that CPT-K5 cells had acquired additional structural aberrations and a reduced modal chromosomal number compared to RPMI-8402. soaCGH analysis identified vast copy number alterations and >200 unbalanced DNA breakpoints distributed unevenly across the chromosomal complement in CPT-K5. In addition, the short tandem repeat alleles were found to be highly different between CPT-K5 and its parental cell line. We identified copy number alterations affecting genes important for maintaining genome integrity and reducing CPT-induced DNA damage. We show for the first time that short tandem repeats are targets for TOP1 cleavage, that can be differentially stimulated by CPT.

Digital object identifier (DOI): 10.21873/cgp.20068

The FEBS journal, 285, 3769--3785
2018

Naphthalene diimide-derivatives G-quadruplex ligands induce cell proliferation inhibition, mild telomeric dysfunction and cell cycle perturbation in U251MG glioma cells.

Muoio, Daniela, Berardinelli, Francesco, Leone, Stefano, Coluzzi, Elisa, di Masi, Alessandra, Doria, Filippo, Freccero, Mauro, Sgura, Antonella, Folini, Marco, Antoccia, Antonio

In the present paper, the biological effects of three different naphthalene diimides (NDIs) G-quadruplex (G4) ligands (H-NDI-Tyr, H-NDI-NMe2, and tetra-NDI-NMe2) were comparatively evaluated to those exerted by RHPS4, a well-characterized telomeric G4-ligand, in an in vitro model of glioblastoma. Data indicated that NDIs were very effective in blocking cell proliferation at nanomolar concentrations, although displaying a lower specificity for telomere targeting compared to RHPS4. In addition, differently from RHPS4, NDIs failed to enhance the effect of ionizing radiation, thus suggesting that additional targets other than telomeres could be involved in the strong NDI-mediated anti-proliferative effects. In order to test telomeric off-target action of NDIs, a panel of genes involved in tumor progression, DNA repair, telomere maintenance, and cell-cycle regulation were evaluated at transcriptional and translational level. Specifically, the compounds were able to cause a marked reduction of TERT and BCL2 amounts as well as to favor the accumulation of proteins involved in cell cycle control. A detailed cytofluorimetric analysis of cell cycle progression by means of bromodeoxyuridine (BrdU) incorporation and staining of phospho-histone H3 indicated that NDIs greatly reduce the progression through S-phase and lead to G1 accumulation of BrdU-positive cells. Taken together, these data indicated that, besides effects on telomeres and oncogenes such as Tert and Bcl2, nanomolar concentrations of NDIs determined a sustained block of cell proliferation by slowing down cell cycle progression during S-phase. In conclusion, our data indicate that NDIs G4-ligands are powerful antiproliferative agents, which act through mechanisms that ultimately lead to altered cell-cycle control.

Digital object identifier (DOI): 10.1111/febs.14628

Cancers, 10
2018

The Transition between Telomerase and ALT Mechanisms in Hodgkin Lymphoma and Its Predictive Value in Clinical Outcomes.

M'kacher, Radhia, Cuceu, Corina, Al Jawhari, Mustafa, Morat, Luc, Frenzel, Monika, Shim, Grace, Lenain, Aude, Hempel, William M, Junker, Steffen, Girinsky, Theodore, Colicchio, Bruno, Dieterlen, Alain, Heidingsfelder, Leonhard, Borie, Claire, Oudrhiri, Noufissa, Bennaceur-Griscelli, Annelise, Moralès, Olivier, Renaud, Sarah, Van de Wyngaert, Zoé, Jeandidier, Eric, Delhem, Nadira, Carde, Patrice

: We analyzed telomere maintenance mechanisms (TMMs) in lymph node samples from HL patients treated with standard therapy. The TMMs correlated with clinical outcomes of patients. : Lymph node biopsies obtained from 38 HL patients and 24 patients with lymphadenitis were included in this study. Seven HL cell lines were used as in vitro models. Telomerase activity (TA) was assessed by TRAP assay and verified through hTERT immunofluorescence expression; alternative telomere lengthening (ALT) was also assessed, along with EBV status. : Both TA and ALT mechanisms were present in HL lymph nodes. Our findings were reproduced in HL cell lines. The highest levels of TA were expressed in CD30-/CD15- cells. Small cells were identified with ALT and TA. Hodgkin and Reed Sternberg cells contained high levels of PML bodies, but had very low hTERT expression. There was a significant correlation between overall survival ( < 10 ), event-free survival ( < 10 ), and freedom from progression ( < 10 ) and the presence of an ALT profile in lymph nodes of EBV+ patients. : The presence of both types of TMMs in HL lymph nodes and in HL cell lines has not previously been reported. TMMs correlate with the treatment outcome of EBV+ HL patients.

Digital object identifier (DOI): 10.3390/cancers10060169

Cancers, 10
2018

Establishment and Characterization of a Reliable Xenograft Model of Hodgkin Lymphoma Suitable for the Study of Tumor Origin and the Design of New Therapies.

M'kacher, Radhia, Frenzel, Monika, Al Jawhari, Mustafa, Junker, Steffen, Cuceu, Corina, Morat, Luc, Bauchet, Anne-Laure, Stimmer, Lev, Lenain, Aude, Dechamps, Nathalie, Hempel, William M, Pottier, Geraldine, Heidingsfelder, Leonhard, Laplagne, Eric, Borie, Claire, Oudrhiri, Noufissa, Jouni, Dima, Bennaceur-Griscelli, Annelise, Colicchio, Bruno, Dieterlen, Alain, Girinsky, Theodore, Boisgard, Raphael, Bourhis, Jean, Bosq, Jacques, Mehrling, Thomas, Jeandidier, Eric, Carde, Patrice

To identify the cells responsible for the initiation and maintenance of Hodgkin lymphoma (HL) cells, we have characterized a subpopulation of HL cells grown in vitro and in vivo with the aim of establishing a reliable and robust animal model for HL. To validate our model, we challenged the tumor cells in vivo by injecting the alkylating histone-deacetylase inhibitor, EDO-S101, a salvage regimen for HL patients, into xenografted mice. Blood lymphocytes from 50 HL patients and seven HL cell lines were used. Immunohistochemistry, flow cytometry, and cytogenetics analyses were performed. The in vitro and in vivo effects of EDO-S101 were assessed. We have successfully determined conditions for in vitro amplification and characterization of the HL L428-c subline, containing a higher proportion of CD30-/CD15- cells than the parental L428 cell line. This subline displayed excellent clonogenic potential and reliable reproducibility upon xenografting into immunodeficient NOD-SCID-gamma (-/-)(NSG) mice. Using cell sorting, we demonstrate that CD30-/CD15- subpopulations can gain the phenotype of the L428-c cell line in vitro. Moreover, the human cells recovered from the seventh week after injection of L428-c cells into NSG mice were small cells characterized by a high frequency of CD30-/CD15- cells. Cytogenetic analysis demonstrated that they were diploid and showed high telomere instability and telomerase activity. Accordingly, chromosomal instability emerged, as shown by the formation of dicentric chromosomes, ring chromosomes, and breakage/fusion/bridge cycles. Similarly, high telomerase activity and telomere instability were detected in circulating lymphocytes from HL patients. The beneficial effect of the histone-deacetylase inhibitor EDO-S101 as an anti-tumor drug validated our animal model. Our HL animal model requires only 10³ cells and is characterized by a high survival/toxicity ratio and high reproducibility. Moreover, the cells that engraft in mice are characterized by a high frequency of small CD30-/CD15- cells exhibiting high telomerase activity and telomere dysfunction.

Digital object identifier (DOI): 10.3390/cancers10110414

eLife, 7
2018

Distinct roles of ATM and ATR in the regulation of ARP8 phosphorylation to prevent chromosome translocations.

Sun, Jiying, Shi, Lin, Kinomura, Aiko, Fukuto, Atsuhiko, Horikoshi, Yasunori, Oma, Yukako, Harata, Masahiko, Ikura, Masae, Ikura, Tsuyoshi, Kanaar, Roland, Tashiro, Satoshi

Chromosomal translocations are hallmarks of various types of cancers and leukemias. However, the molecular mechanisms of chromosome translocations remain largely unknown. The ataxia-telangiectasia mutated (ATM) protein, a DNA damage signaling regulator, facilitates DNA repair to prevent chromosome abnormalities. Previously, we showed that ATM deficiency led to the 11q23 chromosome translocation, the most frequent chromosome abnormalities in secondary leukemia. Here, we show that ARP8, a subunit of the INO80 chromatin remodeling complex, is phosphorylated after etoposide treatment. The etoposide-induced phosphorylation of ARP8 is regulated by ATM and ATR, and attenuates its interaction with INO80. The ATM-regulated phosphorylation of ARP8 reduces the excessive loading of INO80 and RAD51 onto the breakpoint cluster region. These findings suggest that the phosphorylation of ARP8, regulated by ATM, plays an important role in maintaining the fidelity of DNA repair to prevent the etoposide-induced 11q23 abnormalities.

Digital object identifier (DOI): 10.7554/eLife.32222

Basic and clinical andrology, 28, 5
2018

Is sperm FISH analysis still useful for Robertsonian translocations? Meiotic analysis for 23 patients and review of the literature.

Lamotte, Anna, Martinez, Guillaume, Devillard, Françoise, Hograindleur, Jean-Pascal, Satre, Véronique, Coutton, Charles, Harbuz, Radu, Amblard, Florence, Lespinasse, James, Benchaib, Mehdi, Bessonnat, Julien, Brouillet, Sophie, Hennebicq, Sylviane

Robertsonian translocations (RobT) are common structural chromosome rearrangements where carriers display a majority of chromosomally balanced spermatozoa from alternate segregation mode. According to some monotony observed in the rates of balanced segregation, is sperm FISH analysis obsolete for RobT carriers? Retrospective cohort research study on 23 patients analyzed in our center from 2003 to 2017 and compared to the data of 187 patients in literature from 1983 to 2017.Robertsonian translocation carriers were divided in six groups according to the chromosomes involved in the translocation: 9 patients from our center and 107 from literature carrying 45,XY,der(13;14) karyotype, 3 and 35 patients respectively with 45,XY,der(14;21), 5 and 11 patients respectively with 45,XY,der(13;15), 4 and 7 patients respectively with 45,XY,der(14;15), 1 and 4 patients respectively with 45,XY,der(13;22),and 1 and 10 patients respectively with 45,XY,der(14;22). Alternate segregation mode is predominant in our group of Robertsonian translocation carriers with 73.45% ±8.05 of balanced spermatozoa (min 50.92%; max 89.99%). These results are compliant with the data from literature for all translocations types (  > 0.05) and are consistent among the different types of Robertsonian translocations (  > 0.05) except for der(13;15) that exhibit lower balanced spermatozoa rates (  < 0.05 versus der(13;14), der(14;21), (13;21) and der(15;22)). Normozoospermic patients also display a significantly (  < 0.01) higher rate of balanced sperm cells than patients with abnormal seminograms whatever the defect implied. According to the discrepancies observed between der(13;15) and all the other Rob T carriers, the differences observed among patients presenting normal and abnormal sperm parameters and the input in genetical counselling, sperm FISH does not seem obsolete for these patients. Moreover, it seems important to collect more data for rare RobT.

Digital object identifier (DOI): 10.1186/s12610-018-0069-z

Scientific Reports, 8(1), 1141
2018

First experimental proof of Proton Boron Capture Therapy (PBCT) to enhance protontherapy effectiveness

Cirrone, GAP, Manti, L, Margarone, D, Petringa, G, Giuffrida, L, Minopoli, A, Picciotto, A, Russo, G, Cammarata, F, Pisciotta, P, others

Protontherapy is hadrontherapy’s fastest-growing modality and a pillar in the battle against cancer. Hadrontherapy’s superiority lies in its inverted depth-dose profile, hence tumour-confined irradiation. Protons, however, lack distinct radiobiological advantages over photons or electrons. Higher LET (Linear Energy Transfer) 12C-ions can overcome cancer radioresistance: DNA lesion complexity increases with LET, resulting in efficient cell killing, i.e. higher Relative Biological Effectiveness (RBE). However, economic and radiobiological issues hamper 12C-ion clinical amenability. Thus, enhancing proton RBE is desirable. To this end, we exploited the p + 11B → 3α reaction to generate high-LET alpha particles with a clinical proton beam. To maximize the reaction rate, we used sodium borocaptate (BSH) with natural boron content. Boron-Neutron Capture Therapy (BNCT) uses 10B-enriched BSH for neutron irradiation-triggered alpha particles. We recorded significantly increased cellular lethality and chromosome aberration complexity. A strategy combining protontherapy’s ballistic precision with the higher RBE promised by BNCT and 12C-ion therapy is thus demonstrated.

Investigative ophthalmology & visual science, 59, 561--571
2018

A Novel C-Terminal Mutation in Gsdma3 (C+/H-) Leads to Alopecia and Corneal Inflammatory Response in Mice.

Swirski, Sebastian, Röger, Carsten, Pienkowska-Schelling, Aldona, Ihlenburg, Cynthia, Fischer, Gösta, May, Oliver, Vorm, Mariann, Owczarek-Lipska, Marta, Neidhardt, John

Mutations in the gene encoding Gasdermin A3 (Gsdma3) have been described to cause severe skin phenotypes, including loss of sebaceous glands and alopecia, in mice. We discovered a novel C-terminal mutation in Gsdma3 in a new mouse line and characterized a less frequently reported corneal phenotype, likely caused by degeneration of Meibomian glands of the inner eyelid. We used histologic methods to evaluate the effects of the C+/H- mutation on sebaceous gland and skin morphology as well as Meibomian glands of the inner eyelid and corneal tissue. Chromosomal aberrations were excluded by karyogram analyses. The mutation was identified by Sanger sequencing of candidate genes. Analyses of skin samples from affected mice confirmed the frequently reported phenotypes associated with mutations in Gsdma3: Degeneration of sebaceous glands and complete loss of pelage. Immunologic staining of corneal samples suggested an inflammatory response with signs of neovascularization in half of the affected older mice. While the corneal phenotype was observed at irregular time points, mainly after 6 months, its appearance coincided with a degeneration of Meibomian glands in the eyelids of affected animals. The mutation described herein is associated with inflammation and neovascularization of corneal tissue. Simultaneous degeneration of Meibomian glands in affected animals suggested a change in tear-film composition as the underlying cause for the corneal phenotype. Our data further support that different pathogenic mechanisms underlie some of the reported mutations in Gsdma3.

Digital object identifier (DOI): 10.1167/iovs.17-22658

Cancers, 10
2018

Independent Mechanisms Lead to Genomic Instability in Hodgkin Lymphoma: Microsatellite or Chromosomal Instability , [email protected], .

Cuceu, Corina, Colicchio, Bruno, Jeandidier, Eric, Junker, Steffen, Plassa, François, Shim, Grace, Mika, Justyna, Frenzel, Monika, Al Jawhari, Mustafa, Hempel, William M, O'Brien, Grainne, Lenain, Aude, Morat, Luc, Girinsky, Theodore, Dieterlen, Alain, Polanska, Joanna, Badie, Christophe, Carde, Patrice, M'Kacher, Radhia

: Microsatellite and chromosomal instability have been investigated in Hodgkin lymphoma (HL). : We studied seven HL cell lines (five Nodular Sclerosis (NS) and two Mixed Cellularity (MC)) and patient peripheral blood lymphocytes (100 NS-HL and 23 MC-HL). Microsatellite instability (MSI) was assessed by PCR. Chromosomal instability and telomere dysfunction were investigated by FISH. DNA repair mechanisms were studied by transcriptomic and molecular approaches. : In the cell lines, we observed high MSI in L428 (4/5), KMH2, and HDLM2 (3/5), low MSI in L540, L591, and SUP-HD1, and none in L1236. NS-HL cell lines showed telomere shortening, associated with alterations of nuclear shape. Small cells were characterized by telomere loss and deletion, leading to chromosomal fusion, large nucleoplasmic bridges, and breakage/fusion/bridge (B/F/B) cycles, leading to chromosomal instability. The MC-HL cell lines showed substantial heterogeneity of telomere length. Intrachromosmal double strand breaks induced dicentric chromosome formation, high levels of micronucleus formation, and small nucleoplasmic bridges. B/F/B cycles induced complex chromosomal rearrangements. We observed a similar pattern in circulating lymphocytes of NS-HL and MC-HL patients. Transcriptome analysis confirmed the differences in the DNA repair pathways between the NS and MC cell lines. In addition, the NS-HL cell lines were radiosensitive and the MC-cell lines resistant to apoptosis after radiation exposure. : In mononuclear NS-HL cells, loss of telomere integrity may present the first step in the ongoing process of chromosomal instability. Here, we identified, MSI as an additional mechanism for genomic instability in HL.

Digital object identifier (DOI): 10.3390/cancers10070233

Molecular cytogenetics, 11, 4
2018

Is cancer progression caused by gradual or simultaneous acquisitions of new chromosomes?

Bloomfield, Mathew, Duesberg, Peter

Foulds defined, "Tumor progression (as a) permanent, irreversible qualitative change in one or more of its characters" (Cancer Res. 1954). Accordingly progressions, such as metastases and acquired drug-resistance, were since found to be subspecies of cancers with conserved and numerous new chromosomes. Here we ask whether cancers acquire numerous new chromosomes gradually or simultaneously in progressions. The currently prevailing theory of Nowell (Science, 1976) holds that unexplained "genetic instability" generates "variant sublines (with) changes in chromosome number" and that "clonal" progressions arise by "stepwise selection of more aggressive sublines". The literature, however, contains many examples of "immediate" selections of progressions with numerous new chromosomes - notably experimentally initiated fusions between cancers and heterologous cells. Furthermore, the stepwise progression theory predicts intermediate sublines of cancers with multiple non-clonal additions of new chromosomes. However, the literature does not describe such intermediates. In view of these inconsistencies with stepwise progression we test here a saltational theory, in which the inherent variability of cancer-specific aneuploidy generates "immediate" progressions with individual clonal karyotypes, transcriptomes and phenotypes in single steps. Using cell fusion as an established controllable model of "immediate" progression, we generated seven immortal murine hybridomas by fusing immortal murine myeloma cells and normal antibody-producing B-cells with polyethylene glycol within a few minutes. These immortal hybridomas contained individual sets of 71 to 105 clonal chromosomes, compared to the 52 chromosomes of the parental myeloma. Thus the myeloma had gained 19 to 53 new clonal chromosomes in seven individual hybridomas in a single step. Furthermore, no stable intermediates were found, as would be predicted by a saltational process. We conclude that random fusions between myelomas and normal B-cells generate clonal hybridomas with multiple, individual chromosomes in single steps. Similar single-step mechanisms may also generate the "late" clonal progressions of cancers with gains of numerous new chromosomes and thus explain the absence of intermediates. Latency would reflect the low probability of rare stochastic progressions. In conclusion, the karyotypic clonality of hybridomas and spontaneous progressions suggests karyotypic alterations as proximate causes of neoplastic progressions. Since cancer-specific aneuploidy catalyzes karyotypic variation, the degree of aneuploidy predicts the clinical risk of neoplastic progression onfirming classical predictions based on DNA content

Digital object identifier (DOI): 10.1186/s13039-017-0350-4

British journal of cancer
2018

Heterogeneous MYCN amplification in neuroblastoma: a SIOP Europe Neuroblastoma Study.

Berbegall, Ana P, Bogen, Dominik, Pötschger, Ulrike, Beiske, Klaus, Bown, Nick, Combaret, Valérie, Defferrari, Raffaella, Jeison, Marta, Mazzocco, Katia, Varesio, Luigi, Vicha, Ales, Ash, Shifra, Castel, Victoria, Coze, Carole, Ladenstein, Ruth, Owens, Cormac, Papadakis, Vassilios, Ruud, Ellen, Amann, Gabriele, Sementa, Angela R, Navarro, Samuel, Ambros, Peter F, Noguera, Rosa, Ambros, Inge M

In neuroblastoma (NB), the most powerful prognostic marker, the MYCN amplification (MNA), occasionally shows intratumoural heterogeneity (ITH), i.e. coexistence of MYCN-amplified and non-MYCN-amplified tumour cell clones, called heterogeneous MNA (hetMNA). Prognostication and therapy allocation are still unsolved issues. The SIOPEN Biology group analysed 99 hetMNA NBs focussing on the prognostic significance of MYCN ITH. Patients <18 months (18?m) showed a better outcome in all stages as compared to older patients (5-year OS in localised stages: <18?m: 0.95?±?0.04, >18?m: 0.67?±?0.14, p?=?0.011; metastatic: <18?m: 0.76?±?0.15, >18?m: 0.28?±?0.09, p?=?0.084). The genomic 'background', but not MNA clone sizes, correlated significantly with relapse frequency and OS. No relapses occurred in cases of only numerical chromosomal aberrations. Infiltrated bone marrows and relapse tumour cells mostly displayed no MNA. However, one stage 4s tumour with segmental chromosomal aberrations showed a homogeneous MNA in the relapse. This study provides a rationale for the necessary distinction between heterogeneous and homogeneous MNA. HetMNA tumours have to be evaluated individually, taking age, stage and, most importantly, genomic background into account to avoid unnecessary upgrading of risk/overtreatment, especially in infants, as well as in order to identify tumours prone to developing homogeneous MNA.

Digital object identifier (DOI): 10.1038/s41416-018-0098-6

Journal of Alzheimer's disease : JAD, 61, 899--905
2018

A Novel Antibody Targeting Tau Phosphorylated at Serine 235 Detects Neurofibrillary Tangles.

Brici, David, Götz, Jürgen, Nisbet, Rebecca M

Alzheimer's disease is characterized by two main pathological hallmarks in the human brain: the extracellular deposition of amyloid-β as plaques and the intracellular accumulation of the hyperphosphorylated protein tau as neurofibrillary tangles (NFTs). Phosphorylated tau (p-tau) specific-antibodies and silver staining have been used to reveal three morphological stages of NFT formation: pre-NFTs, intraneuronal NFTs (iNFTs), and extraneuronal NFTs (eNFTs). Here we characterize a novel monoclonal antibody, RN235, which is specific for tau phosphorylated at serine 235, and detects iNFTs and eNFTs in brain tissue, suggesting that phosphorylation at this site is indicative of late stage changes in tau.

Digital object identifier (DOI): 10.3233/JAD-170610

Journal of clinical pathology
2018

KRAS fluorescence in situ hybridisation testing for the detection and diagnosis of pancreatic adenocarcinoma.

Shiroma, Noriyuki, Arihiro, Koji, Oda, Miyo, Orita, Makoto

The aim of our study was to analyse correlations between mutation status, chromosomal changes that affect status in cells from pancreatic tumours. We collected 69 cases of surgically resected pancreatic ductal adenocarcinoma (PDA) and seven cases of chronic pancreatitis (CP). Chromosomal abnormalities of and CEP12 were detected using fluorescence in situ hybridisation (FISH). The number of CEP12 signals per cell ranged from 1.78 to 2.04 and 1.46 to 4.88 in CP and PDA samples, respectively, while the number of signals per cell ranged from 1.94 to 2.06 and 1.88 to 8.18 in CP and PDA samples, respectively. The 'chromosomal instability index', which was defined as the percentage of cells with any chromosomal abnormality, was over 5.7 times greater in PDA than in CP. We performed mutation analysis by direct sequencing and found that tumours with mutations have a significantly higher mean signal per cell from PDA samples compared with tumours with wild-type amplification was noted in 10% of cases. Although we found that lymph node metastasis and distal metastasis of PDA were more frequent in cases with amplification, this was not correlated with overall survival. Using a threshold of 40%, we found that the chromosomal instability index robustly discriminated PDA cells from CP cells. Based on these findings, we concluded that FISH testing of using cytology samples may represent an accurate approach for the diagnosis of PDA.

Digital object identifier (DOI): 10.1136/jclinpath-2018-205002

eLife, 6
2017

Epigenetic regulation of lateralized fetal spinal gene expression underlies hemispheric asymmetries.

Ocklenburg, Sebastian, Schmitz, Judith, Moinfar, Zahra, Moser, Dirk, Klose, Rena, Lor, Stephanie, Kunz, Georg, Tegenthoff, Martin, Faustmann, Pedro, Francks, Clyde, Epplen, Jörg T, Kumsta, Robert, Güntürkün, Onur

Lateralization is a fundamental principle of nervous system organization but its molecular determinants are mostly unknown. In humans, asymmetric gene expression in the fetal cortex has been suggested as the molecular basis of handedness. However, human fetuses already show considerable asymmetries in arm movements before the motor cortex is functionally linked to the spinal cord, making it more likely that spinal gene expression asymmetries form the molecular basis of handedness. We analyzed genome-wide mRNA expression and DNA methylation in cervical and anterior thoracal spinal cord segments of five human fetuses and show development-dependent gene expression asymmetries. These gene expression asymmetries were epigenetically regulated by miRNA expression asymmetries in the TGF-β signaling pathway and lateralized methylation of CpG islands. Our findings suggest that molecular mechanisms for epigenetic regulation within the spinal cord constitute the starting point for handedness, implying a fundamental shift in our understanding of the ontogenesis of hemispheric asymmetries in humans.

Digital object identifier (DOI): 10.7554/eLife.22784

Leukemia
2017

RECQ1 helicase is involved in replication stress survival and drug resistance in multiple myeloma.

Viziteu, E, Klein, B, Basbous, J, Lin, Y-L, Hirtz, C, Gourzones, C, Tiers, L, Bruyer, A, Vincent, L, Grandmougin, C, Seckinger, A, Goldschmidt, H, Constantinou, A, Pasero, P, Hose, D, Moreaux, J

Multiple myeloma (MM) is a plasma cell cancer with poor survival, characterized by the expansion of multiple myeloma cells (MMCs) in the bone marrow. Using a microarray-based genome-wide screen for genes responding to DNA methyltransferases (DNMT) inhibition in MM cells, we identified RECQ1 among the most downregulated genes. RecQ helicases are DNA unwinding enzymes involved in the maintenance of chromosome stability. Here we show that RECQ1 is significantly overexpressed in MMCs compared to normal plasma cells and that increased RECQ1 expression is associated with poor prognosis in three independent cohorts of patients. Interestingly, RECQ1 knockdown inhibits cells growth and induces apoptosis in MMCs. Moreover, RECQ1 depletion promotes the development of DNA double-strand breaks, as evidenced by the formation of 53BP1 foci and the phosphorylation of ataxia-telangiectasia mutated (ATM) and histone variant H2A.X (H2AX). In contrast, RECQ1 overexpression protects MMCs from melphalan and bortezomib cytotoxicity. RECQ1 interacts with PARP1 in MMCs exposed to treatment and RECQ1 depletion sensitizes MMCs to poly(ADP-ribose) polymerase (PARP) inhibitor. DNMT inhibitor treatment results in RECQ1 downregulation through miR-203 deregulation in MMC. Altogether, these data suggest that association of DNA damaging agents and/or PARP inhibitors with DNMT inhibitors may represent a therapeutic approach in patients with high RECQ1 expression associated with a poor prognosis.Leukemia advance online publication, 10 March 2017; doi:10.1038/leu.2017.54.

Digital object identifier (DOI): 10.1038/leu.2017.54

Oncotarget, 8, 26269--26280
2017

Opposite effects of GCN5 and PCAF knockdowns on the alternative mechanism of telomere maintenance.

Jeitany, Maya, Bakhos-Douaihy, Dalal, Silvestre, David C, Pineda, Jose R, Ugolin, Nicolas, Moussa, Angela, Gauthier, Laurent R, Busso, Didier, Junier, Marie-Pierre, Chneiweiss, Hervé, Chevillard, Sylvie, Desmaze, Chantal, Boussin, François D

Cancer cells can use a telomerase-independent mechanism, known as alternative lengthening of telomeres (ALT), to elongate their telomeres. General control non-derepressible 5 (GCN5) and P300/CBP-associated factor (PCAF) are two homologous acetyltransferases that are mutually exclusive subunits in SAGA-like complexes. Here, we reveal that down regulation of GCN5 and PCAF had differential effects on some phenotypic characteristics of ALT cells. Our results suggest that GCN5 is present at telomeres and opposes telomere recombination, in contrast to PCAF that may indirectly favour them in ALT cells.

Digital object identifier (DOI): 10.18632/oncotarget.15447