@article{RudeliusRosenfeldtLeichetal.2019, author = {Rudelius, Martina and Rosenfeldt, Mathias Tillmann and Leich, Ellen and Rauert-Wunderlich, Hilka and Solimando, Antonio Giovanni and Ott, German and Rosenwald, Andreas and Beilhack, Andreas}, title = {Inhibition of focal adhesion kinase overcomes resistance of mantle cell lymphoma to ibrutinib in the bone marrow microenvironment}, series = {Haematologica}, volume = {103}, journal = {Haematologica}, number = {1}, doi = {10.3324/haematol.2017.177162}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-227117}, pages = {116-125}, year = {2019}, abstract = {Mantle cell lymphoma and other lymphoma subtypes often spread to the bone marrow, and stromal interactions mediated by focal adhesion kinase frequently enhance survival and drug resistance of the lymphoma cells. To study the role of focal adhesion kinase in mantle cell lymphoma, immunohistochemistry of primary cases and functional analysis of mantle cell lymphoma cell lines and primary mantle cell lymphoma cells co-cultured with bone marrow stromal cells (BMSC) using small molecule inhibitors and RNAi-based focal adhesion kinase silencing was performed. We showed that focal adhesion kinase is highly expressed in bone marrow infiltrates of mantle cell lymphoma and in mantle cell lymphoma cell lines. Stroma-mediated activation of focal adhesion kinase led to activation of multiple kinases (AKT, p42/44 and NF-kappa B), that are important for prosurvival and proliferation signaling. Interestingly, RNAi-based focal adhesion kinase silencing or inhibition with small molecule inhibitors (FAKi) resulted in blockage of targeted cell invasion and induced apoptosis by inactivation of multiple signaling cascades, including the classic and alternative NF-kappa B pathway. In addition, the combined treatment of ibrutinib and FAKi was highly synergistic, and ibrutinib resistance of mantle cell lymphoma could be overcome. These data demonstrate that focal adhesion kinase is important for stroma-mediated survival and drug resistance in mantle cell lymphoma, providing indications for a targeted therapeutic strategy.}, subject = {Multiple}, language = {en} } @article{RauertWunderlichBerberichRosenwaldetal.2018, author = {Rauert-Wunderlich, Hilka and Berberich, Ingolf and Rosenwald, Andreas and Rudelius, Martina}, title = {CD40L mediated alternative NF kappa B-signaling induces resistance to BCR-inhibitors in patients with mantle cell lymphoma}, series = {Cell Death \& Disease}, journal = {Cell Death \& Disease}, number = {9}, doi = {10.1038/s41419-017-0157-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225027}, pages = {86, 1-9}, year = {2018}, abstract = {Drug resistance is a significant obstacle in cancer treatment and therefore a frequent subject of research. Developed or primary resistance limits the treatment success of inhibitors of the B cell receptor (BCR) pathway in mantle cell lymphoma (MCL) patients. Recent research has highlighted the role of the nuclear factor-kappa B (NF kappa B) pathway in the context of resistance to BCR inhibitors in MCL. In this study, we analyzed the dependency of MCL cell lines on NF kappa B signaling and illustrated the ability of CD40L to activate the alternative NF kappa B pathway in MCL. This activation leads to independency of classical NF kappa B signaling and results in resistance to BCR inhibitors. Therefore, ligands (such as CD40L) and their activation of the alternative NF kappa B pathway have a major impact on the drug response in MCL. Furthermore, this study indicates a protective role for cells expressing specific ligands as microenvironmental niches for MCL cells and underlines the significance of therapeutically targeting alternative NF kappa B signaling in MCL.}, language = {en} } @article{RegnLaggerbauerJentzschetal.2016, author = {Regn, Michael and Laggerbauer, Bernhard and Jentzsch, Claudia and Ramanujam, Deepak and Ahles, Andrea and Sichler, Sonja and Calzada-Wack, Julia and Koenen, Rory R. and Braun, Attila and Nieswandt, Bernhard and Engelhardt, Stefan}, title = {Peptidase inhibitor 16 is a membrane-tethered regulator of chemerin processing in the myocardium}, series = {Journal of Molecular and Cellular Cardiology}, volume = {99}, journal = {Journal of Molecular and Cellular Cardiology}, doi = {10.1016/j.yjmcc.2016.08.010}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-187039}, pages = {57-64}, year = {2016}, abstract = {A key response of the myocardium to stress is the secretion of factors with paracrine or endocrine function. Intriguing in this respect is peptidase inhibitor 16 (PI16), a member of the CAP family of proteins which we found to be highly upregulated in cardiac disease. Up to this point, the mechanism of action and physiological function of PI16 remained elusive. Here, we show that PI16 is predominantly expressed by cardiac fibroblasts, which expose PI16 to the interstitium via a glycophosphatidylinositol (-GPI) membrane anchor. Based on a reported genetic association of PI16 and plasma levels of the chemokine chemerin, we investigated whether PI16 regulates post-translational processing of its precursor pro-chemerin. PI16-deficient mice were engineered and found to generate higher levels of processed chemerin than wildtype mice. Purified recombinant PI16 efficiently inhibited cathepsin K, a chemerin-activating protease, in vitro. Moreover, we show that conditioned medium from PI16-overexpressing cells impaired the activation of pro-chemerin. Together, our data indicate that PI16 suppresses chemerin activation in the myocardium and suggest that this circuit may be part of the cardiac stress response.}, language = {en} } @article{HerbertKuebler2011, author = {Herbert, Cornelia and K{\"u}bler, Andrea}, title = {Dogs Cannot Bark: Event-Related Brain Responses to True and False Negated Statements as Indicators of Higher-Order Conscious Processing}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {10}, doi = {10.1371/journal.pone.0025574}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135165}, pages = {e25574}, year = {2011}, abstract = {The present study investigated event-related brain potentials elicited by true and false negated statements to evaluate if discrimination of the truth value of negated information relies on conscious processing and requires higher-order cognitive processing in healthy subjects across different levels of stimulus complexity. The stimulus material consisted of true and false negated sentences (sentence level) and prime-target expressions (word level). Stimuli were presented acoustically and no overt behavioral response of the participants was required. Event-related brain potentials to target words preceded by true and false negated expressions were analyzed both within group and at the single subject level. Across the different processing conditions (word pairs and sentences), target words elicited a frontal negativity and a late positivity in the time window from 600-1000 msec post target word onset. Amplitudes of both brain potentials varied as a function of the truth value of the negated expressions. Results were confirmed at the single-subject level. In sum, our results support recent suggestions according to which evaluation of the truth value of a negated expression is a time-and cognitively demanding process that cannot be solved automatically, and thus requires conscious processing. Our paradigm provides insight into higher-order processing related to language comprehension and reasoning in healthy subjects. Future studies are needed to evaluate if our paradigm also proves sensitive for the detection of consciousness in non-responsive patients.}, language = {en} } @article{GowdaGodderKmieciaketal.2011, author = {Gowda, Madhu and Godder, Kamar and Kmieciak, Maciej and Worschech, Andrea and Ascierto, Maria-Libera and Wang, Ena and Francesco M., Marincola and Manjili, Masoud H.}, title = {Distinct signatures of the immune responses in low risk versus high risk neuroblastoma}, series = {Journal of Translational Medicine}, volume = {9}, journal = {Journal of Translational Medicine}, number = {170}, doi = {10.1186/1479-5876-9-170}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135147}, pages = {1-8}, year = {2011}, abstract = {Background: Over 90\% of low risk (LR) neuroblastoma patients survive whereas less than 30\% of high risk (HR) patients are long term survivors. Age (children younger than 18 months old) is associated with LR disease. Considering that adaptive immune system is well developed in older children, and that T cells were shown to be involved in tumor escape and progression of cancers, we sought to determine whether HR patients may tend to show a signature of adaptive immune responses compared to LR patients who tend to have diminished T-cell responses but an intact innate immune response. Methods: We performed microarray analysis of RNA extracted from the tumor specimens of HR and LR patients. Flow cytometry was performed to determine the cellular constituents in the blood while multiplex cytokine array was used to detect the cytokine profile in patients' sera. A HR tumor cell line, SK-N-SH, was also used for detecting the response to IL-1 beta, a cytokines which is involved in the innate immune responses. Results: Distinct patterns of gene expression were detected in HR and LR patients indicating an active T-cell response and a diminished adaptive immune response, respectively. A diminished adaptive immune response in LR patients was evident by higher levels of IL-10 in the sera. In addition, HR patients had lower levels of circulating myeloid derived suppressor cells (MDSC) compared with a control LR patient. LR patients showed slightly higher levels of cytokines of the innate immune responses. Treatment of the HR tumor line with IL-1b induced expression of cytokines of the innate immune responses. Conclusions: This data suggests that adaptive immune responses may play an important role in the progression of HR disease whereas innate immune responses may be active in LR patients.}, language = {en} } @article{CeteciXuCetecietal.2011, author = {Ceteci, Fatih and Xu, Jiajia and Ceteci, Semra and Zanucco, Emanuele and Thakur, Chitra and Rapp, Ulf R.}, title = {Conditional Expression of Oncogenic C-RAF in Mouse Pulmonary Epithelial Cells Reveals Differential Tumorigenesis and Induction of Autophagy Leading to Tumor Regression}, series = {Neoplasia}, volume = {13}, journal = {Neoplasia}, number = {11}, doi = {10.1593/neo.11652}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134347}, pages = {1005-1018}, year = {2011}, abstract = {Here we describe a novel conditional mouse lung tumor model for investigation of the pathogenesis of human lung cancer. On the basis of the frequent involvement of the Ras-RAF-MEK-ERK signaling pathway in human non-small cell lung carcinoma (NSCLC), we have explored the target cell availability, reversibility, and cell type specificity of transformation by oncogenic C-RAF. Targeting expression to alveolar type II cells or to Clara cells, the two likely precursors of human NSCLC, revealed differential tumorigenicity between these cells. Whereas expression of oncogenic C-RAF in alveolar type II cells readily induced multifocal macroscopic lung tumors independent of the developmental state, few tumors with type II pneumocytes features and incomplete penetrance were found when targeted to Clara cells. Induced tumors did not progress and were strictly dependent on the initiating oncogene. Deinduction of mice resulted in tumor regression due to autophagy rather than apoptosis. Induction of autophagic cell death in regressing lung tumors suggests the use of autophagy enhancers as a treatment choice for patients with NSCLC.}, language = {en} } @article{vonBuerenOehlerShalabyetal.2011, author = {von Bueren, Andr{\´e} O. and Oehler, Christoph and Shalaby, Tarek and von Hoff, Katja and Pruschy, Martin and Seifert, Burkhardt and Gerber, Nicolas U. and Warmuth-Metz, Monika and Stearns, Duncan and Eberhart, Charles G. and Kortmann, Rolf D. and Rutkowski, Stefan and Grotzer, Michael A.}, title = {c-MYC expression sensitizes medulloblastoma cells to radio- and chemotherapy and has no impact on response in medulloblastoma patients}, series = {BMC Cancer}, volume = {11}, journal = {BMC Cancer}, number = {74}, doi = {10.1186/1471-2407-11-74}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134185}, pages = {1-11}, year = {2011}, abstract = {Background: To study whether and how c-MYC expression determines response to radio-and chemotherapy in childhood medulloblastoma (MB). Methods: We used DAOY and UW228 human MB cells engineered to stably express different levels of c-MYC, and tested whether c-MYC expression has an effect on radio-and chemosensitivity using the colorimetric 3-(4,5-dimethylthiazol- 2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay, clonogenic survival, apoptosis assays, cell cycle analysis, and western blot assessment. In an effort to validate our results, we analyzed c-MYC mRNA expression in formalin-fixed paraffin-embedded tumor samples from well-documented patients with postoperative residual tumor and compared c-MYC mRNA expression with response to radio-and chemotherapy as examined by neuroradiological imaging. Results: In DAOY -and to a lesser extent in UW228 -cells expressing high levels of c-MYC, the cytotoxicity of cisplatin, and etoposide was significantly higher when compared with DAOY/UW228 cells expressing low levels of c-MYC. Irradiation-and chemotherapy-induced apoptotic cell death was enhanced in DAOY cells expressing high levels of c-MYC. The response of 62 of 66 residual tumors was evaluable and response to postoperative radio-(14 responders (CR, PR) vs. 5 non-responders (SD, PD)) or chemotherapy (23 CR/PR vs. 20 SD/PD) was assessed. c-MYC mRNA expression was similar in primary MB samples of responders and non-responders (Mann-Whitney U test, p = 0.50, ratio 0.49, 95\% CI 0.008-30.0 and p = 0.67, ratio 1.8, 95\% CI 0.14-23.5, respectively). Conclusions: c-MYC sensitizes MB cells to some anti-cancer treatments in vitro. As we failed to show evidence for such an effect on postoperative residual tumors when analyzed by imaging, additional investigations in xenografts and larger MB cohorts may help to define the exact function of c-MYC in modulating response to treatment.}, language = {en} } @article{RantamaekiVesaAntilaetal.2011, author = {Rantam{\"a}ki, Tomi and Vesa, Liisa and Antila, Hanna and Di Lieto, Antonio and Tammela, P{\"a}ivi and Schmitt, Angelika and Lesch, Klaus-Peter and Rios, Maribel and Castr{\´e}n, Eero}, title = {Antidepressant Drugs Transactivate TrkB Neurotrophin Receptors in the Adult Rodent Brain Independently of BDNF and Monoamine Transporter Blockade}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {6}, doi = {10.1371/journal.pone.0020567}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133746}, pages = {e20567}, year = {2011}, abstract = {Background: Antidepressant drugs (ADs) have been shown to activate BDNF (brain-derived neurotrophic factor) receptor TrkB in the rodent brain but the mechanism underlying this phenomenon remains unclear. ADs act as monoamine reuptake inhibitors and after prolonged treatments regulate brain bdnf mRNA levels indicating that monoamine-BDNF signaling regulate AD-induced TrkB activation in vivo. However, recent findings demonstrate that Trk receptors can be transactivated independently of their neurotrophin ligands. Methodology: In this study we examined the role of BDNF, TrkB kinase activity and monoamine reuptake in the AD-induced TrkB activation in vivo and in vitro by employing several transgenic mouse models, cultured neurons and TrkB-expressing cell lines. Principal Findings: Using a chemical-genetic TrkB(F616A) mutant and TrkB overexpressing mice, we demonstrate that ADs specifically activate both the maturely and immaturely glycosylated forms of TrkB receptors in the brain in a TrkB kinase dependent manner. However, the tricyclic AD imipramine readily induced the phosphorylation of TrkB receptors in conditional bdnf(-/-) knock-out mice (132.4+/-8.5\% of control; P = 0.01), indicating that BDNF is not required for the TrkB activation. Moreover, using serotonin transporter (SERT) deficient mice and chemical lesions of monoaminergic neurons we show that neither a functional SERT nor monoamines are required for the TrkB phosphorylation response induced by the serotonin selective reuptake inhibitors fluoxetine or citalopram, or norepinephrine selective reuptake inhibitor reboxetine. However, neither ADs nor monoamine transmitters activated TrkB in cultured neurons or cell lines expressing TrkB receptors, arguing that ADs do not directly bind to TrkB. Conclusions: The present findings suggest that ADs transactivate brain TrkB receptors independently of BDNF and monoamine reuptake blockade and emphasize the need of an intact tissue context for the ability of ADs to induce TrkB activity in brain.}, language = {en} } @article{FischerMaierSiegemundetal.2011, author = {Fischer, Roman and Maier, Olaf and Siegemund, Martin and Wajant, Harald and Scheurich, Peter and Pfizenmaier, Klaus}, title = {A TNF Receptor 2 Selective Agonist Rescues Human Neurons from Oxidative Stress-Induced Cell Death}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {11}, doi = {10.1371/journal.pone.0027621}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133552}, pages = {e27621}, year = {2011}, abstract = {Tumor necrosis factor (TNF) plays a dual role in neurodegenerative diseases. Whereas TNF receptor (TNFR) 1 is predominantly associated with neurodegeneration, TNFR2 is involved in tissue regeneration and neuroprotection. Accordingly, the availability of TNFR2-selective agonists could allow the development of new therapeutic treatments of neurodegenerative diseases. We constructed a soluble, human TNFR2 agonist (TNC-scTNF(R2)) by genetic fusion of the trimerization domain of tenascin C to a TNFR2-selective single-chain TNF molecule, which is comprised of three TNF domains connected by short peptide linkers. TNC-scTNFR2 specifically activated TNFR2 and possessed membrane-TNF mimetic activity, resulting in TNFR2 signaling complex formation and activation of downstream signaling pathways. Protection from neurodegeneration was assessed using the human dopaminergic neuronal cell line LUHMES. First we show that TNC-scTNF(R2) interfered with cell death pathways subsequent to H(2)O(2) exposure. Protection from cell death was dependent on TNFR2 activation of the PI3K-PKB/Akt pathway, evident from restoration of H(2)O(2) sensitivity in the presence of PI3K inhibitor LY294002. Second, in an in vitro model of Parkinson disease, TNC-scTNFR(2) rescues neurons after induction of cell death by 6-OHDA. Since TNFR2 is not only promoting anti-apoptotic responses but also plays an important role in tissue regeneration, activation of TNFR2 signaling by TNC-scTNF(R2) appears a promising strategy to ameliorate neurodegenerative processes.}, language = {en} } @article{RauertStuehmerBargouetal.2011, author = {Rauert, H. and St{\"u}hmer, T. and Bargou, R. and Wajant, H. and Siegmund, D.}, title = {TNFR1 and TNFR2 regulate the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms}, series = {Cell Death and Disease}, volume = {2}, journal = {Cell Death and Disease}, doi = {10.1038/cddis.2011.78}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133486}, pages = {e194}, year = {2011}, abstract = {The huge majority of myeloma cell lines express TNFR2 while a substantial subset of them failed to show TNFR1 expression. Stimulation of TNFR1 in the TNFR1-expressing subset of MM cell lines had no or only a very mild effect on cellular viability. Surprisingly, however, TNF stimulation enhanced cell death induction by CD95L and attenuated the apoptotic effect of TRAIL. The contrasting regulation of TRAIL- and CD95L-induced cell death by TNF could be traced back to the concomitant NFjBmediated upregulation of CD95 and the antiapoptotic FLIP protein. It appeared that CD95 induction, due to its strength, overcompensated a rather moderate upregulation of FLIP so that the net effect of TNF-induced NFjB activation in the context of CD95 signaling is pro-apoptotic. TRAIL-induced cell death, however, was antagonized in response to TNF because in this context only the induction of FLIP is relevant. Stimulation of TNFR2 in myeloma cells leads to TRAF2 depletion. In line with this, we observed cell death induction in TNFR1-TNFR2-costimulated JJN3 cells. Our studies revealed that the TNF-TNF receptor system adjusts the responsiveness of the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms that generate a highly context-dependent net effect on myeloma cell survival}, language = {en} }