Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • DKFZ Publication Database  (8)
Collection
  • Articles  (143)
  • DKFZ Publication Database  (8)
  • 1
    Keywords: CELLS ; IN-VITRO ; TYROSINE KINASE ; DISEASE ; PROTEIN ; TRANSDUCTION ; MECHANISM ; DOMAIN ; SIGNAL-TRANSDUCTION ; ABERRATIONS ; LOCALIZATION ; CHRONIC MYELOID-LEUKEMIA ; GENETIC INSTABILITY ; FUSION PROTEIN ; CLONAL EVOLUTION ; centrosome ; TYROSINE KINASES ; FACTOR RECEPTOR-BETA ; PDGFR ; CHRONIC MYELOMONOCYTIC LEUKEMIA ; chronic myeloproliferative disorder ; MYELOGENOUS LEUKEMIA ; PCM1-JAK2 FUSION
    Abstract: Constitutive tyrosine kinase activation by reciprocal chromosomal translocation is a common pathogenetic mechanism in chronic myeloproliferative disorders. Since centrosomal proteins have been recurrently identified as translocation partners of tyrosine kinases FGFR1, JAK2, PDGFR alpha and PDGFR beta in these diseases, a role for the centrosome in oncogenic transformation has been hypothesized. In this study, we addressed the functional role of centrosomally targeted tyrosine kinase activity. First, centrosomal localization was not routinely found for all chimeric fusion proteins tested. Second, targeting of tyrosine kinases to the centrosome by creating artificial chimeric fusion kinases with the centrosomal targeting domain of AKAP450 failed to enhance the oncogenic transforming potential in both Ba/F3 and U2OS cells, although phospho-tyrosine-mediated signal transduction pathways were initiated at the centrosome. We conclude that the centrosomal localization of constitutively activated tyrosine kinases does not contribute to disease pathogenesis in chronic myeloproliferative disorders.
    Type of Publication: Journal article published
    PubMed ID: 22015771
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Abstract: Background: Recent studies have reported mutations in the telomerase reverse transcriptase promoter (TERTp) in meningiomas. We sought to determine the frequency, clonality and clinical significance of telomere gene alterations in a cohort of patients with progressive/higher-grade meningiomas. Methods: We characterized 64 temporally- and regionally-distinct specimens from 26 WHO grade III meningioma patients. On initial diagnoses, the meningiomas spanned all WHO grades (3 grade I, 13 grade II and 10 grade III). The tumor samples were screened for TERTp and ATRX/DAXX mutations, and TERT rearrangements. Additionally, TERTp was sequenced in a separate cohort of 19 patients with radiation-associated meningiomas. We examined the impact of mutational status on patients' progression and overall survival. Results: Somatic TERTp mutations were detected in six patients (6/26 = 23%). Regional intratumoral heterogeneity in TERTp mutation status was noted. In 4 patients, TERTp mutations were detected in recurrent specimens but not in the available specimens of the first surgery. Additionally, a TERT gene fusion (LPCAT1-TERT) was found in one sample. In contrary, none of the investigated samples harbored an ATRX or DAXX mutation. In the cohort of radiation-induced meningiomas, TERTp mutation was detected in two patients (10.5%). Importantly, we found that patients with emergence of TERTp mutations had a substantially shorter OS than their TERTp wild-type counterparts (2.7 years, 95% CI 0.9 - 4.5 years versus 10.8 years, 95% CI 7.8 -12.8 years, p=0.003). Conclusions: In progressive/higher-grade meningiomas,TERTp mutations are associated with poor survival, supporting a model in which selection of this alteration is a harbinger of aggressive tumor development. In addition, we observe spatial intratumoral heterogeneity of TERTp mutation status, consistent with this model of late emergence in tumor evolution. Thus, early detection of TERTp mutations may define patients with more aggressive meningiomas. Stratification for TERT alterations should be adopted in future clinical trials of progressive/higher-grade meningiomas.
    Type of Publication: Journal article published
    PubMed ID: 29312603
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    Keywords: APOPTOSIS ; CELLS ; EXPRESSION ; IN-VITRO ; CELL ; Germany ; human ; INHIBITION ; KINASE ; MODEL ; PATHWAY ; PATHWAYS ; VITRO ; COMPONENTS ; DIFFERENTIATION ; ACTIVATION ; DENDRITIC CELLS ; PHOSPHORYLATION ; SCHIZOPHRENIA ; TARGET ; COMPONENT ; MODULATION ; beta-catenin ; TARGETS ; HIGH-LEVEL ; secretion ; SYNTHASE ; development ; CYTOKINE PRODUCTION ; LEVEL ; ENZYME ; GLYCOGEN-SYNTHASE KINASE-3 ; function ; depression ; INHIBIT ; BIPOLAR DISORDER ; LITHIUM TREATMENT
    Abstract: The key components of the intracellular molecular network required for the expression of a specific function of dendritic cells (DCs) are as yet undefined. Using an in vitro model of human monocyte-derived DC differentiation, this study investigates the role of glycogen synthase kinase 3 (GSK-3), a multifunctional enzyme critical for cellular differentiation, apoptosis, self-renewal, and motility, in this context. We demonstrate that GSK-3 (1) inhibits macrophage development during differentiation of DCs, (2) is constitutively active in immature DCs and suppresses spontaneous maturation, and (3) acquires a proinflammatory functional status mediating high levels of IL-12, IL-6, and TNF-alpha secretion, and partially inhibits IL-10 in the context of DC activation. In particular, GSK-3 enhances IL-12p35 mRNA expression and thus the production of the proinflammatory cytokine IL-12p70 by integrating the activities of other kinases priming GSK-3 targets and the inhibitory effects of Akt-1. GSK-3 may therefore act as a key integrator of activating and inhibitory pathways involved in proinflammatory DC differentiation and activation
    Type of Publication: Journal article published
    PubMed ID: 17032918
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    Keywords: NERVOUS-SYSTEM ; NEURITE OUTGROWTH ; CELL-ADHESION MOLECULE ; RAT-BRAIN ; TUMOR-SUPPRESSOR ; DEFICIENT MICE ; EPITHELIAL OVARIAN-CANCER ; INCREASED ENERGY-EXPENDITURE ; IGLON FAMILY ; HETEROPHILIC INTERACTIONS
    Abstract: To date, genome-wide association studies (GWAS) have identified at least 32 novel loci for obesity and body mass-related traits. However, the causal genetic variant and molecular mechanisms of specific susceptibility genes in relation to obesity are yet to be fully confirmed and characterised. Here, we examined whether the candidate gene NEGR1 encoding the neuronal growth regulator 1, also termed neurotractin or Kilon, accounts for the obesity association. To characterise the function of NEGR1 for body weight control in vivo, we generated two novel mutant mouse lines, including a constitutive NEGR1-deficient mouse line as well as an ENU-mutagenised line carrying a loss-of-function mutation (Negr1-I87N) and performed metabolic phenotypic analyses. Ablation of NEGR1 results in a small but steady reduction of body mass in both mutant lines, accompanied with a small reduction in body length in the Negr1-I87N mutants. Magnetic resonance scanning reveals that the reduction of body mass in Negr1-I87N mice is due to a reduced proportion of lean mass. Negr1-I87N mutants display reduced food intake and physical activity while normalised energy expenditure remains unchanged. Expression analyses confirmed the brain-specific distribution of NEGR1 including strong expression in the hypothalamus. In vitro assays show that NEGR1 promotes cell-cell adhesion and neurite growth of hypothalamic neurons. Our results indicate a role of NEGR1 in the control of body weight and food intake. This study provides evidence that supports the link of the GWAS candidate gene NEGR1 with body weight control.
    Type of Publication: Journal article published
    PubMed ID: 22844493
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    Keywords: CELLS ; EXPRESSION ; CELL ; Germany ; KINASE ; MODEL ; PATHWAY ; PATHWAYS ; VOLUME ; DEATH ; transcription ; NF-KAPPA-B ; ACTIVATION ; LIGAND ; INDUCTION ; CONTRAST ; DENDRITIC CELLS ; LYMPH-NODES ; SIGNAL ; FORM ; DIFFERENCE ; CELL-DEATH ; SIGNALING PATHWAYS ; MIGRATION ; ONCOGENE ; ATHEROSCLEROSIS ; immune response ; IMMUNE-RESPONSE ; PERIPHERAL-BLOOD ; CD4(+) T-CELLS ; F ; AUTOIMMUNITY ; CYTOKINE ; PERSISTENT ; NODES ; RE ; STRENGTH ; CD40 LIGAND ; CD40-CD40 LIGAND ; IL-12 PRODUCTION ; PHYSIOLOGICAL STIMULI
    Abstract: Migration to lymph nodes and secretion of cytokines are critical functions of mature dendritic cells (DCs); however, these 2 functions are not necessarily linked. This is the first report showing that quantitative differences in identical signaling pathways determine DC migration and cytokine secretion. Using different polymerized forms of CD40 ligand, we demonstrate that the strength and persistence of CD40 signaling can induce either function. Induction of monocyte-derived DC (MoDC) migration required a weak and transient CD40 signal, whereas strong and persistent CD40 signaling blocked migration and biased toward cytokine secretion. In contrast to MoDCs, CD40 activation of CD1c(+) peripheral blood DCs (PBDCs) induced a nonpersistent, intracellular signaling profile resulting in migratory-type DCs unable to secrete interleukin-12p70 (IL-12p70). Extracellular signal-regulated kinase 1/2 (ERK1/2) and p38K activation synergistically mediated cytokine secretion, whereas migration was enhanced by p38K activation but reduced by persistent ERK1/2 activity. This model of signal strength and persistence also applied when stimulating DCs with intact microbes. Thus, a novel concept emerges in which the type of immune response induced by DCs is tuned by the strength and persistence of DC activating signals. (C) 2004 by The American Society of Hematology
    Type of Publication: Journal article published
    PubMed ID: 15113760
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Keywords: CANCER ; EXPRESSION ; SURVIVAL ; tumor ; Germany ; SYSTEM ; HYBRIDIZATION ; TIME ; PATIENT ; DNA ; NUCLEI ; IN-SITU ; AMPLIFICATION ; COMPARATIVE GENOMIC HYBRIDIZATION ; MUTATION ; REPAIR ; chemotherapy ; ABERRATIONS ; HETEROZYGOSITY ; inactivation ; p53 ; FISH ; MUTATIONS ; FLUORESCENCE ; relapse ; LOCATION ; ALLELIC LOSS ; 1p ; clonality ; in situ hybridization ; molecular ; INTERVAL ; cytogenetic ; oligoastrocytoma ; 19Q ; ADJUVANT CHEMOTHERAPY ; MISMATCH-REPAIR ; anaplastic ; HUMAN ASTROCYTOMAS ; metachronous ; MIXED OLIGOASTROCYTOMAS ; OLIGODENDROGLIAL TUMORS
    Abstract: Two metachronous anaplastic oligoastrocytomas with different cerebral locations were analyzed in a 51-year-old patient with an extended recurrence-free interval of 6 years and an a long survival of 9 years. Remarkably, the patient had not undergone adjuvant chemotherapy. Different cytogenetic and molecular techniques were performed including comparative genomic hybridization (CGH), fluorescence in situ hybridization (FISH), allelic loss analysis, sequencing of p53, p16(INK4a)/CDKN2A and p14(ARF), EGFRamplification studies, investigation of the DNA mismatch repair system as well as tumor clonality. Using CGH and FISH a profile of low accumulation of cytogenetic aberrations was found in the second tumor, with no significant increase in the percentage of hyperdiploid nuclei. Microsatellite analysis showed a common pattern of allelic losses at 1p36, 19q13 and 9p21. Both specimens were also similar in that they retained heterozygosity at 10q23-q24 and 13q14 and that they harbor neither EGFR amplification nor mutations of p53, p16(INK4a)/CDKN2A or p14(ARF). The only further alteration in the second tumor was an allelic loss at p53. The X-chromosome inactivation (HUMARA) analysis revealed a polyclonal pattern in both samples. Our data strongly suggest that the second anaplastic oligoastrocytoma developed as a distant relapse of the first tumor. Whether the paucity of accumulation of the observed genetic alterations might be associated with the unusually extended relapse-free time of the patient remains to be elucidated
    Type of Publication: Journal article published
    PubMed ID: 15925987
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Keywords: CELLS ; EXPRESSION ; Germany ; INHIBITION ; KINASE ; PATHWAY ; PATHWAYS ; DISTINCT ; DIFFERENTIATION ; TIME ; ACTIVATION ; INFECTION ; CONTRAST ; DENDRITIC CELLS ; SIGNAL ; NUMBER ; SIGNALING PATHWAY ; SIGNALING PATHWAYS ; MIGRATION ; Jun ; INDIVIDUALS ; sensitivity ; ADAPTIVE IMMUNITY ; CYCLIC-AMP ; ORGANIZATION ; signaling ; CYTOKINE ; RE ; secretion ; SOLID TUMORS ; IL-12 PRODUCTION ; LEVEL ; NEGATIVE REGULATION ; PHOSPHATIDYLINOSITOL 3-KINASE ; PERSISTENCE ; function ; Mol Oncol ; VARIABLES ; PROTEIN-KINASE-A ; VARIETIES ; RAF ; CYTOKINE SECRETION ; MIGRATORY CAPACITY
    Abstract: Phenotypic maturation, cytokine secretion, and migration are distinct functional characteristics of dendritic cells (DCs). These functions are independently regulated by a number of extracellular variables, such as type, strength, and persistence of an array of soluble and membrane-bound mediators. Since the exact composition of these variables in response to infection may differ between individuals, the intracellular signaling pathways activated by these extracellular networks may more closely correlate with DC function and predict the course of adaptive immunity. We found that activation of p38 kinase (p38K), extracellular signal-related kinase 1/2 (ERK1/2), and phosphatidylcholine-specific phospholipase C (PC-PLC) enhanced cytokine secretion, whereas p38K, cyclic adenosine monophosphate (cAMP), and PC-PLC enhanced migration. In contrast, phosphatidylinositol 3-kinase (PI3K)/Akt-1 and cAMP inhibited cytokine secretion while ERK1/2 inhibited migration. Migration and cytokine secretion further differed in their sensitivity to inhibition over time. However, although DCs could be manipulated to express migration, cytokine secretion, or both, the level of activation or persistence of intracellular pathway signaling was not predictive. Our results suggest a modular organization of function. We hypothesize that the expression of specific DC functions integrates a large variety of activating and inhibitory variables, and is represented by the formation of a functional unit of molecular networks-the signal response module (SRM). The combined activities of these modules define the functional outcome of DC activation
    Type of Publication: Journal article published
    PubMed ID: 16527899
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    Keywords: mechanisms ; DYNAMICS ; CANCER-CELLS ; INSTABILITY ; ORIENTATION ; INTEGRIN-LINKED KINASE ; CENTROSOME AMPLIFICATION ; EXTRA CENTROSOMES ; MICROTUBULE-ORGANIZING CENTERS ; DYNEIN
    Abstract: Accurate mitotic spindle positioning is essential for the regulation of cell fate choices, cell size and cell position within tissues. The most prominent model of spindle positioning involves a cortical pulling mechanism, where the minus end-directed microtubule motor protein dynein is attached to the cell cortex and exerts pulling forces on the plus ends of astral microtubules that reach the cortex. In nonpolarized cultured cells integrin-dependent, retraction fiber-mediated cell adhesion is involved in spindle orientation. Proteins serving as intermediaries between cortical actin or retraction fibers and astral microtubules remain largely unknown. In a recent genome-wide RNAi screen we identified a previously uncharacterized protein, MISP (C19ORF21) as being involved in centrosome clustering, a process leading to the clustering of supernumerary centrosomes in cancer cells into a bipolar mitotic spindle array by microtubule tension. Here, we show that MISP is associated with the actin cytoskeleton and focal adhesions and is expressed only in adherent cell types. During mitosis MISP is phosphorylated by Cdk1 and localizes to retraction fibers. MISP interacts with the +TIP EB1 and p150(glued), a subunit of the dynein/dynactin complex. Depletion of MISP causes mitotic arrest with reduced tension across sister kinetochores, chromosome misalignment and spindle multipolarity in cancer cells with supernumerary centrosomes. Analysis of spindle orientation revealed that MISP depletion causes randomization of mitotic spindle positioning relative to cell axes and cell center. Together, we propose that MISP links microtubules to the actin cytoskeleton and focal adhesions in order to properly position the mitotic spindle.
    Type of Publication: Journal article published
    PubMed ID: 23574715
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...