15 research outputs found

    Basic Hallmarks of Urothelial Cancer Unleashed in Primary Uroepithelium by Interference with the Epigenetic Master Regulator ODC1

    Full text link
    Urothelial carcinoma (UC) is a common disease causing significant morbidity and mortality as well as considerable costs for health systems. Extensive aberrant methylation of DNA is broadly documented in early UC, contributing to genetic instability, altered gene expression and tumor progression. However the triggers initiating aberrant methylation are unknown. Recently we discovered that several genes encoding key enzymes of methyl group and polyamine metabolism, including Ornithine Decarboxylase 1 (ODC1), are affected by DNA methylation in early stage UC. In this study, we investigated the hypothesis that these epigenetic alterations act in a feed-forward fashion to promote aberrant DNA methylation in UC. We demonstrate that siRNA-mediated knockdown of ODC1 expression elicits genome-wide LINE-1 demethylation, induction of LINE-1 transcripts and double-strand DNA breaks and decreases viability in primary cultured uroepithelial cells. Similarly, following siRNA-mediated knockdown of ODC1, UC cells undergo double-strand DNA breaks and apoptosis. Collectively, our findings provide evidence that ODC1 gene hypermethylation could be a starting point for the onset of genome-wide epigenetic aberrations in urothelial carcinogenesis. Furthermore, LINE-1 induction enabled by ODC1 interference provides a new experimental model to study mechanisms and consequences of LINE-1 activation in the etiology and progression of UC as well as presumably other cancers

    IDLN-MSP: Idiolocal normalization of real-time methylation-specific PCR for genetic imbalanced DNA specimens

    Full text link
    Sensitive, accurate, and reliable measurements of tumor cell-specific DNA methylation changes are of fundamental importance in cancer diagnosis, prognosis, and monitoring. Real-time methylation-specific PCR (MSP) using intercalating dyes is an established method of choice for this purpose. Here we present a simple but crucial adaptation of this widely applied method that overcomes a major obstacle: genetic abnormalities in the DNA samples, such as aneuploidy or copy number variations, that could result in inaccurate results due to improper normalization if the copy numbers of the target and reference sequences are not the same. In our idiolocal normalization (IDLN) method, the locus for the normalizing, methylation-independent reference amplification is chosen close to the locus of the methylation-dependent target amplification. This ensures that the copy numbers of both the target and reference sequences will be identical in most cases if they are close enough to each other, resulting in accurate normalization and reliable comparative measurements of DNA methylation in clinical samples when using real-time MSP

    Consistent DNA Hypomethylations in Prostate Cancer

    No full text
    With approximately 1.4 million men annually diagnosed with prostate cancer (PCa) worldwide, PCa remains a dreaded threat to life and source of devastating morbidity. In recent decades, a significant decrease in age-specific PCa mortality has been achieved by increasing prostate-specific antigen (PSA) screening and improving treatments. Nevertheless, upcoming, augmented recommendations against PSA screening underline an escalating disproportion between the benefit and harm of current diagnosis/prognosis and application of radical treatment standards. Undoubtedly, new potent diagnostic and prognostic tools are urgently needed to alleviate this tensed situation. They should allow a more reliable early assessment of the upcoming threat, in order to enable applying timely adjusted and personalized therapy and monitoring. Here, we present a basic study on an epigenetic screening approach by Methylated DNA Immunoprecipitation (MeDIP). We identified genes associated with hypomethylated CpG islands in three PCa sample cohorts. By adjusting our computational biology analyses to focus on single CpG-enriched 60-nucleotide-long DNA probes, we revealed numerous consistently differential methylated DNA segments in PCa. They were associated among other genes with NOTCH3, CDK2AP1, KLK4, and ADAM15. These can be used for early discrimination, and might contribute to a new epigenetic tumor classification system of PCa. Our analysis shows that we can dissect short, differential methylated CpG-rich DNA fragments and combinations of them that are consistently present in all tumors. We name them tumor cell-specific differential methylated CpG dinucleotide signatures (TUMS)

    Unreserved application of epigenetic methods to define differences of DNA methylation between urinary cellular and cell-free DNA

    Full text link
    Urinary DNA is increasingly gaining importance in diagnosis of urological malignancies. Especially cell-free DNA originating from apoptotic and necrotic cells of the early tumor could become a key target for early stage tumor diagnosis. Aberrant DNA methylation forms tumor cell characteristic epigenetic profiles which are covalently established before any tumor related aberration at transcriptional or protein level has occurred. In addition, these epigenetic signatures are alterably adapted to and accompanying the individual stages of multistep, progressive tumorigenesis. Hence, they seem very promising for diagnosis as well as for monitoring the patient's follow-up care and even for decisions regarding personalized therapeutic options. The essential prerequisite at this approach will be a reliable methodological handling of the biological material of interest. In this study we present detailed analyses of LINE-1 DNA methylation profiles and demonstrate the sensitive detection of LINE-1 DNA methylation differences as well as between cancer patients and healthy individuals, between urinary cellular and cell-free DNA. In addition, we show methylome differences between both DNA fractions from a healthy individual and bladder cancer patients. In conclusion, we demonstrate here the unrestricted amenability of urinary cell-free DNA for both, a detailed characterization of a distinct DNA methylation alteration and its sensitive detection and a comprehensive global, array-based screening for DNA methylation differences

    Search for Scalar Diphoton Resonances in the Mass Range 6560065-600 GeV with the ATLAS Detector in pppp Collision Data at s\sqrt{s} = 8 TeVTeV

    No full text
    A search for scalar particles decaying via narrow resonances into two photons in the mass range 65–600 GeV is performed using 20.3fb120.3\text{}\text{}{\mathrm{fb}}^{-1} of s=8TeV\sqrt{s}=8\text{}\text{}\mathrm{TeV} pppp collision data collected with the ATLAS detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95% confidence level on the production cross section of a scalar boson times branching ratio into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches

    Search for Higgs and ZZ Boson Decays to J/ψγJ/\psi\gamma and Υ(nS)γ\Upsilon(nS)\gamma with the ATLAS Detector

    No full text
    A search for the decays of the Higgs and ZZ bosons to J/ψγJ/\psi\gamma and Υ(nS)γ\Upsilon(nS)\gamma (n=1,2,3n=1,2,3) is performed with pppp collision data samples corresponding to integrated luminosities of up to 20.3fb120.3\mathrm{fb}^{-1} collected at s=8TeV\sqrt{s}=8\mathrm{TeV} with the ATLAS detector at the CERN Large Hadron Collider. No significant excess of events is observed above expected backgrounds and 95% CL upper limits are placed on the branching fractions. In the J/ψγJ/\psi\gamma final state the limits are 1.5×1031.5\times10^{-3} and 2.6×1062.6\times10^{-6} for the Higgs and ZZ bosons, respectively, while in the Υ(1S,2S,3S)γ\Upsilon(1S,2S,3S)\,\gamma final states the limits are (1.3,1.9,1.3)×103(1.3,1.9,1.3)\times10^{-3} and (3.4,6.5,5.4)×106(3.4,6.5,5.4)\times10^{-6}, respectively

    Measurements of the Total and Differential Higgs Boson Production Cross Sections Combining the H??????? and H???ZZ*???4??? Decay Channels at s\sqrt{s}=8??????TeV with the ATLAS Detector

    No full text
    Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3~fb1^{-1} of pppp collisions produced by the Large Hadron Collider at a center-of-mass energy of s=8\sqrt{s} = 8 TeV and recorded by the ATLAS detector. Cross sections are obtained from measured HγγH \rightarrow \gamma \gamma and HZZ4H \rightarrow ZZ ^{*}\rightarrow 4\ell event yields, which are combined accounting for detector efficiencies, fiducial acceptances and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σppH=33.0±5.3(stat)±1.6(sys)pb\sigma_{pp \to H} = 33.0 \pm 5.3 \, ({\rm stat}) \pm 1.6 \, ({\rm sys}) \mathrm{pb}. The measurements are compared to state-of-the-art predictions.Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3  fb-1 of pp collisions produced by the Large Hadron Collider at a center-of-mass energy of s=8  TeV and recorded by the ATLAS detector. Cross sections are obtained from measured H→γγ and H→ZZ*→4ℓ event yields, which are combined accounting for detector efficiencies, fiducial acceptances, and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σpp→H=33.0±5.3 (stat)±1.6 (syst)  pb. The measurements are compared to state-of-the-art predictions.Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3 fb1^{-1} of pppp collisions produced by the Large Hadron Collider at a center-of-mass energy of s=8\sqrt{s} = 8 TeV and recorded by the ATLAS detector. Cross sections are obtained from measured HγγH \rightarrow \gamma \gamma and HZZ4H \rightarrow ZZ ^{*}\rightarrow 4\ell event yields, which are combined accounting for detector efficiencies, fiducial acceptances and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σppH=33.0±5.3(stat)±1.6(sys)pb\sigma_{pp \to H} = 33.0 \pm 5.3 \, ({\rm stat}) \pm 1.6 \, ({\rm sys}) \mathrm{pb}. The measurements are compared to state-of-the-art predictions
    corecore