80 research outputs found

    Primary Immunodeficiency and Cancer Predisposition Revisited: Embedding Two Closely Related Concepts Into an Integrative Conceptual Framework

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    Common understanding suggests that the normal function of a “healthy” immune system safe-guards and protects against the development of malignancies, whereas a genetically impaired one might increase the likelihood of their manifestation. This view is primarily based on and apparently supported by an increased incidence of such diseases in patients with specific forms of immunodeficiencies that are caused by high penetrant gene defects. As I will review and discuss herein, such constellations merely represent the tip of an iceberg. The overall situation is by far more varied and complex, especially if one takes into account the growing difficulties to define what actually constitutes an immunodeficiency and what defines a cancer predisposition. The enormous advances in genome sequencing, in bioinformatic analyses and in the functional in vitro and in vivo assessment of novel findings together with the availability of large databases provide us with a wealth of information that steadily increases the number of sequence variants that concur with clinically more or less recognizable immunological problems and their consequences. Since many of the newly identified hard-core defects are exceedingly rare, their tumor predisposing effect is difficult to ascertain. The analyses of large data sets, on the other hand, continuously supply us with low penetrant variants that, at least in statistical terms, are clearly tumor predisposing, although their specific relevance for the respective carriers still needs to be carefully assessed on an individual basis. Finally, defects and variants that affect the same gene families and pathways in both a constitutional and somatic setting underscore the fact that immunodeficiencies and cancer predisposition can be viewed as two closely related errors of development. Depending on the particular genetic and/or environmental context as well as the respective stage of development, the same changes can have either a neutral, predisposing and, in some instances, even a protective effect. To understand the interaction between the immune system, be it “normal” or “deficient” and tumor predisposition and development on a systemic level, one therefore needs to focus on the structure and dynamic functional organization of the entire immune system rather than on its isolated individual components alone

    Mesothelioma mortality in Europe: impact of asbestos consumption and simian virus 40

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    BACKGROUND: It is well established that asbestos is the most important cause of mesothelioma. The role of simian virus 40 (SV40) in mesothelioma development, on the other hand, remains controversial. This potential human oncogene has been introduced into various populations through contaminated polio vaccines. The aim of this study was to investigate whether the possible presence of SV40 in various European countries, as indicated either by molecular genetic evidence or previous exposure to SV40-contaminated vaccines, had any effect on pleural cancer rates in the respective countries. METHODS: We conducted a Medline search that covered the period from January 1969 to August 2005 for reports on the detection of SV40 DNA in human tissue samples. In addition, we collected all available information about the types of polio vaccines that had been used in these European countries and their SV40 contamination status. RESULTS: Our ecological analysis confirms that pleural cancer mortality in males, but not in females, correlates with the extent of asbestos exposure 25 – 30 years earlier. In contrast, neither the presence of SV40 DNA in tumor samples nor a previous vaccination exposure had any detectable influence on the cancer mortality rate in neither in males (asbestos-corrected rates) nor in females. CONCLUSION: Using the currently existing data on SV40 prevalence, no association between SV40 prevalence and asbestos-corrected male pleural cancer can be demonstrated

    Clonality Assessment in a Case of Multifocal Adamantinoma and a Review of the Literature

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    Adamantinoma is a low-grade, malignant biphasic bone tumour predominantly located in the tibia. In up to 50% of all cases this is combined with one or more lesions in the ipsilateral fibula. Whether these lesions represent regional metastases or arise de novo is not yet exactly known. In order to address this question, we extracted DNA from the respective fresh frozen tumour tissues in a case of a young woman with a multifocal adamantinoma of both the tibia and ipsilateral fibula. Afterwards the X inactivation pattern was studied by means of methylation-sensitive polymerase chain reaction and primers that target the polymorphic CGG trinucleotide repeat of FMR1 gene and the polymorphic CAG repeat, on exon 1 of the human androgen receptor gene (AR). The analysis of the AR was homozygous and not informative. Studying the FMR1 gene, we detected a 100% skewing of the X inactivation pattern of both locations and found that the same allele was methylated. Even if the fibula lesion arose de novo there would have been a 50 : 50 chance that the same allele was methylated. As this methylation pattern was found we cannot provide a valid explanation for the origin of the fibula lesion. Analysis of X inactivation patterns in future cases of polyfocal adamantinoma might provide further evidence for one of the two theories

    Mutational Analysis of the SOX9 Gene in Campomelic Dysplasia and Autosomal Sex Reversal: Lack of Genotype/Phenotype Correlations

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    It has previously been shown that, in the heterozygous state, mutations in the SOX9 gene cause campomelic dysplasia (CD) and the often associated autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one recurrent mutation were characterized in one SOX9 allele each, and in one case, no mutation was found. Four missense mutations are all located within the high mobility group (HMG) domain. They either reduce or abolish the DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense and three frameshift mutations identified, two leave the C-terminal transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or almost completely intact. When tested in cell transfection experiments, the recurrent nonsense mutation Y440X, found in two patients who survived for four and more than 9 years, respectively, exhibits some residual transactivation ability. In contrast, a frameshift mutation extending the protein by 70 residues at codon 507, found in a patient who died shortly after birth, showed no transactivation. This is apparently due to instability of the mutant SOX9 protein as demonstrated by Western blotting. Amino acid substitutions and nonsense mutations are found in patients with and without XY sex reversal, indicating that sex reversal in CD is subject to variable penetrance. Finally, none of 18 female patients with XY gonadal dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP assays, providing evidence that SOX9 mutations do not usually result in XY sex reversal without skeletal malformation

    The Leukemia-Specific Fusion Gene ETV6/RUNX1 Perturbs Distinct Key Biological Functions Primarily by Gene Repression

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    -positive leukemic cell lines.-positive ALL samples underline the relevance of these pathways and molecular functions. We also validated six differentially expressed genes representing the categories “stem cell properties”, “B-cell differentiation”, “immune response”, “cell adhesion” and “DNA damage” with RT-qPCR. fusion gene interferes with key regulatory functions that shape the biology of this leukemia subtype. E/R may thus indeed constitute the essential driving force for the propagation and maintenance of the leukemic process irrespective of potential consequences of associated secondary changes. Finally, these findings may also provide a valuable source of potentially attractive therapeutic targets

    Beam test performance of a prototype module with Short Strip ASICs for the CMS HL-LHC tracker upgrade

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    The Short Strip ASIC (SSA) is one of the four front-end chips designed for the upgrade of the CMS Outer Tracker for the High Luminosity LHC. Together with the Macro-Pixel ASIC (MPA) it will instrument modules containing a strip and a macro-pixel sensor stacked on top of each other. The SSA provides both full readout of the strip hit information when triggered, and, together with the MPA, correlated clusters called stubs from the two sensors for use by the CMS Level-1 (L1) trigger system. Results from the first prototype module consisting of a sensor and two SSA chips are presented. The prototype module has been characterized at the Fermilab Test Beam Facility using a 120 GeV proton beam

    Epigenetic regulator genes direct lineage switching in MLL/AF4 leukaemia

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    The fusion gene MLL/AF4 defines a high-risk subtype of pro-B acute lymphoblastic leukaemia. Relapse can be associated with a lineage switch from acute lymphoblastic to acute myeloid leukaemia resulting in poor clinical outcomes due to resistance towards chemo- and immuno-therapies. Here we show that the myeloid relapses share oncogene fusion breakpoints with their matched lymphoid presentations and can originate from varying differentiation stages from immature progenitors through to committed B-cell precursors. Lineage switching is linked to substantial changes in chromatin accessibility and rewiring of transcriptional programmes, including alternative splicing. These findings indicate that the execution and maintenance of lymphoid lineage differentiation is impaired. The relapsed myeloid phenotype is recurrently associated with the altered expression, splicing or mutation of chromatin modifiers, including CHD4 coding for the ATPase/helicase of the nucleosome remodelling and deacetylation complex, NuRD. Perturbation of CHD4 alone or in combination with other mutated epigenetic modifiers induces myeloid gene expression in MLL/AF4-positive cell models indicating that lineage switching in MLL/AF4 leukaemia is driven and maintained by disrupted epigenetic regulation
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