Publications by authors named "Thilo Spruss"

Chemerin is a multifunctional adipokine that regulates adipogenesis, insulin signaling and blood pressure and has thus a central function in metabolism. Mounting evidence confirmed a function of chemerin in various cancers. In this study, we investigated the role of chemerin in rhabdomyosarcoma (RMS), an aggressive soft tissue cancer that affects mainly children and young adults.

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Overexpression of the neurotensin receptor type 1 (NTSR), a peptide receptor located at the plasma membrane, has been reported for a variety of malignant tumors. Thus, targeting the NTSR with F- or Ga-labeled ligands is considered a straightforward approach towards in vivo imaging of NTSR-expressing tumors via positron emission tomography (PET). The development of suitable peptidic NTSR PET ligands derived from neurotensin is challenging due to proteolytic degradation.

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Hypothesis: The choice of the material for plugging a dehiscence of the superior semicircular canal is based on the ease of use and the success of the procedure to permanently relieve symptoms without adverse side effects.

Background: Dehiscence of the superior semicircular canal can lead to autophony, conductive hearing loss, and vertigo. Surgical treatment by plugging the canal is a highly effective treatment of the symptoms in many patients, although, the procedure can be associated with some degree of hearing loss in more than or equal to 25% of the patients.

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The network of molecular players is similar when comparing neural crest-derived, actively migrating melanoblasts to melanoma cells. However, melanoblasts are sensitive to differentiation-initiating signals at their target site (epidermis), while melanoma cells maintain migratory and undifferentiated features. We aimed at identifying downregulated genes in melanoma that are particularly upregulated in melanoblasts.

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Unlabelled: Previous observations that human amniotic fluid cells (AFC) can be transformed by human adenovirus type 5 (HAdV-5) E1A/E1B oncogenes prompted us to identify the target cells in the AFC population that are susceptible to transformation. Our results demonstrate that one cell type corresponding to mesenchymal stem/stroma cells (hMSCs) can be reproducibly transformed by HAdV-5 E1A/E1B oncogenes as efficiently as primary rodent cultures. HAdV-5 E1-transformed hMSCs exhibit all properties commonly associated with a high grade of oncogenic transformation, including enhanced cell proliferation, anchorage-independent growth, increased growth rate, and high telomerase activity as well as numerical and structural chromosomal aberrations.

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In human cancers, giant cadherin FAT1 may function both, as an oncogene and a tumor suppressor. Here, we investigated the expression and function of FAT1 in hepatocellular carcinoma (HCC). FAT1 expression was increased in human HCC cell lines and tissues compared with primary human hepatocytes and non-tumorous liver tissue as assessed by quantitative PCR and western blot analysis.

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Melanoma is the most aggressive form of skin cancer, with fast progression and early dissemination mediated by the melanoma inhibitory activity (MIA) protein. Here, we discovered that dimerization of MIA is required for functional activity through mutagenesis of MIA which showed the correlation between dimerization and functional activity. We subsequently identified the dodecapeptide AR71, which prevents MIA dimerization and thereby acts as a MIA inhibitor.

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Augmenter of liver regeneration (ALR), which is critically important in liver regeneration and hepatocyte proliferation, is highly expressed in cirrhotic livers and hepatocellular carcinomas (HCC). In the current study, the functional role of ALR in hepatocancerogenesis was analyzed in more detail. HepG2 cells, in which the cytosolic 15 kDa ALR isoform was reexpressed stably, (HepG2-ALR) were used in migration and invasion assays using modified Boyden chambers.

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Analysis of the molecular mechanisms of viral-mediated oncogenesis has contributed enormously to the understanding of the basic principles of normal/malignant cell growth. Transformation by human adenoviruses is a multi-step process involving the modulation of numerous cellular pathways, leading to inhibition of apoptosis and growth arrest. However, the molecular mechanism of how the adenovirus oncogenes facilitate transformation of rodent cells, while concurrently failing to do so for human cells, remains elusive.

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Fibroblast growth factor receptor 2 isoform b (FGFR2-IIIb) is highly expressed in hepatocytes and plays an important role in liver homeostasis and regeneration. Here, we analyzed the expression and function of FGFR2-IIIb in hepatocellular carcinoma (HCC). FGFR2-IIIb expression in HCC tissues and cell lines was lower than in primary human hepatocytes and nontumorous tissue.

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Liver cirrhosis is the main risk factor for the development of hepatocellular carcinoma (HCC). Activated hepatic stellate cells (HSC) are the effector cells of hepatic fibrosis and also infiltrate the HCC stroma where they might play a critical role in HCC progression. Here we aimed to analyze the effects of activated HSC on the proliferation and growth of HCC cell lines in vitro and in vivo.

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High malignancy and early metastasis are hallmarks of melanoma. Here, we report that the transcription factor Snail1 inhibits expression of the tumor suppressor CYLD in melanoma. As a direct consequence of CYLD repression, the protooncogene BCL-3 translocates into the nucleus and activates Cyclin D1 and N-cadherin promoters, resulting in proliferation and invasion of melanoma cells.

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One strategy of adipose tissue engineering is to transplant adipocytes or adipocyte precursor cells in combination with polymeric materials. However, a satisfying formation of fat tissue and its long-term survival still remain major problems. There is increasing evidence that treatment of the cells prior to implantation plays a critical role in the success of adipose tissue growth.

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Purpose: Previously, we studied the effect of co-administration of paclitaxel with the second generation ABCB1 (p-gp) modulator valspodar on the intracerebral growth of human U118-MG glioblastoma in nude mice. Valspodar significantly increased the brain levels of paclitaxel by inhibition of p-gp expressed at the blood brain barrier. Thus, the tumour burden was reduced by 90%, which was considered as a proof of concept.

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We studied the role of the Transforming growth factor (TGF)-beta signaling antagonist Smad7 in autoimmune central nervous system (CNS) inflammation by using specific antisense oligonucleotides (Smad7-as). Elevated Smad7 protein expression was found in the spinal cord of SJL/J mice and DA rats with experimental autoimmune encephalomyelitis (EAE) and in effector T cells upon antigen stimulation. Smad7-as specifically decreased Smad7 mRNA and protein in cell lines and in ex-vivo-treated primary mouse lymph node cells (LNC).

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The cytokine receptor CD137 is a member of the TNF receptor family and a potent T cell costimulatory molecule. Its ligand is expressed on antigen presenting cells as a transmembrane protein and it too can deliver signals into the cells it is expressed on (reverse signaling). In monocytes, immobilized CD137 protein induces activation, prolongation of survival and proliferation.

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[Meso-1,2-bis(2,6-dihalo-3/4-hydroxyphenyl)ethylenediamine]platinum(II) complexes (meso-1-PtLL': 2,6-F(2),3-OH; meso-2-PtLL': 2,6-F(2),4-OH; meso-3-PtLL': 2,6-Cl(2),3-OH; meso-4-PtLL': 2,6-Cl(2),4-OH; L = OH(2), L' = OSO(3) or L,L' = Cl(2)) were designed with the aim to get drugs comprising both cytotoxic and testosterone level lowering potencies. It is assumed that such compounds are more efficient than the established endocrine therapeutic measures and can affect the development of hormone refractory prostate cancer (PC). With exception of meso-3-PtLL' all Pt-complexes and the comparison compound cisplatin significantly reduced the testosterone level in experiments on male rats.

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Although a few experimental approaches to isolated limb perfusion (ILP) are described in the literature, none of these animal models mimics the clinical perfusion techniques adequately to improve the technique of ILP on the basis of valid preclinical data. Therefore, we developed an ILP setup in rats allowing online monitoring of essential perfusion parameters such as temperature (in perfusate, various tissues, and rectum), pH (perfusate), perfusion pressure, and O(2) concentration (in perfusate, tissue), by a tailor-made data acquisition system. This setup permits close supervision of vital parameters during ILP.

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The 55-kDa gene product from subgroup C adenovirus type 5 (Ad5) early region 1 (E1B-55kDa) plays a central role in the oncogenic transformation of primary rodent cells primarily by inactivating transcriptional and presumably other functional properties of the tumor suppressor protein p53. We have previously shown that Ad5 E1B-55kDa possesses a leucine-rich nuclear export signal (NES), which confers rapid nucleocytoplasmic shuttling via the CRM1-dependent export pathway. In this study we report that an export-deficient mutant of the viral protein (E1B-NES) substantially enhances focus formation of primary baby rat kidney cells in combination with Ad E1A.

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Tissue-inherent factors such as cell-cell and cell-extracellular matrix interactions are regarded to exert a potentially large impact on adipogenesis as well as on secretory functions of adipose tissue. However, an appropriate 3-D adipogenesis model useful for addressing such interactions is still lacking. In this study, using tissue-engineering techniques, we demonstrate for the first time the development of coherent fat pads consisting of unilocular signet-ring cells in vitro.

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The marked activity of [meso-1, 2-bis(2, 6-difluoro-3-hydroxyphenyl)ethylenediamine]platinum(II) (meso-3-PtLL', L, L' = Cl(2) or L = OH(2), L' = OSO(3)) on the hormone-sensitive MXT-M-3, 2 breast cancer implanted in mice is most probably due to a mechanism based on the reduction of the endogenous estrogen level. Cytotoxic effects which are poorly pronounced in experiments on several breast cancer cell lines (e.g.

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Aqua[meso-1, 2-bis(2, 6-difluoro-3-hydroxyphenyl)ethylenediamine]sulfatoplatinum(II) (meso-3-PtSO(4)) and its racemate (rac-3-PtSO(4)) are highly active on the hormone-sensitive MXT-M-3, 2 breast cancer of the mouse. In vitro, on the MXT(+) cell culture derived from this tumor, however, they are inactive (meso-3-PtSO(4)) or moderately active (rac-3-PtSO(4)) in concentrations corresponding to levels of these drugs in animal experiments. The in vivo effect is mainly caused by a reduction of the endogenous estrogen level in the host animals due to an interference with the ovarian steroid biosynthesis as demonstrated for meso-3-PtSO(4).

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Background And Purpose: Middle cerebral artery occlusion (MCAO) by an intraluminal filament is a widely accepted animal model of focal cerebral ischemia. In this procedure, cutting of the external carotid artery (ECA) is a prerequisite for thread insertion. However, the implications of ECA transsection have not yet been described.

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Paclitaxel concentrations in the brain are very low after intravenous injection. Since paclitaxel is excluded from some tumors by p-glycoprotein (p-gp), the same mechanism may prevent entry into the brain. In vitro, paclitaxel transport was examined in capillaries from rat brains by confocal microscopy using BODIPY Fl-paclitaxel.

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The establishment of two new breast cancer cell lines, MXT+ and MXT-, derived from the murine breast cancer models MXT-M-3,2 MC (hormone-sensitive) and MXT-M-3,2 (ovex) MC (hormone-insensitive), is described. Characterization of the cell lines was performed by investigation of morphology, steroid hormone receptor state, growth kinetics, and drug response as well as by cytogenetic analysis. MXT+ contains estrogen receptors (ER; 6.

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