@inproceedings{WernerWakabayashiJahnsetal.2017,
  author    = {Werner, Rudolf and Wakabayashi, Hiroshi and Jahns, Roland and Erg{\"u}n, S{\"u}leyman and Jahns, Valerie and Higuchi, Takahiro},
  title     = {PET-Guided Histological Characterization of Myocardial Infiltrating Cells in a Rat Model of Myocarditis},
  series = {European Heart Journal - Cardiovascular Imaging},
  volume    = {18},
  booktitle = {European Heart Journal - Cardiovascular Imaging},
  number    = {Supplement},
  publisher = {Oxford University Press},
  issn      = {2047-2404},
  doi       = {10.1093/ehjci/jex071},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161127},
  pages     = {i1-i3},
  year      = {2017},
  abstract  = {No abstract available.},
  subject      = {Myokarditis},
  language  = {en}
}
@article{WunschHohmannMillesetal.2016,
  author    = {Wunsch, Marie and Hohmann, Christopher and Milles, Bianca and Rostermund, Christina and Lehmann, Paul V. and Schroeter, Michael and Bayas, Antonios and Ulzheimer, Jochen and M{\"a}urer, Mathias and Erg{\"u}n, S{\"u}leyman and Kuerten, Stefanie},
  title     = {The Correlation between the Virus- and Brain Antigen-Specific B Cell Response in the Blood of Patients with Multiple Sclerosis},
  series = {Viruses},
  volume    = {8},
  journal   = {Viruses},
  number    = {4},
  doi       = {10.3390/v8040105},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146946},
  pages     = {105},
  year      = {2016},
  abstract  = {There is a largely divergent body of literature regarding the relationship between Epstein-Barr virus (EBV) infection and brain inflammation in multiple sclerosis (MS). Here, we tested MS patients during relapse (n = 11) and in remission (n = 19) in addition to n = 22 healthy controls to study the correlation between the EBV- and brain-specific B cell response in the blood by enzyme-linked immunospot (ELISPOT) and enzyme-linked immunosorbent assay (ELISA). Cytomegalovirus (CMV) was used as a control antigen tested in n = 16 MS patients during relapse and in n = 35 patients in remission. Over the course of the study, n = 16 patients were untreated, while n = 33 patients received immunomodulatory therapy. The data show that there was a moderate correlation between the frequencies of EBV- and brain-reactive B cells in MS patients in remission. In addition we could detect a correlation between the B cell response to EBV and disease activity. There was no evidence of an EBV reactivation. Interestingly, there was also a correlation between the frequencies of CMV- and brain-specific B cells in MS patients experiencing an acute relapse and an elevated B cell response to CMV was associated with higher disease activity. The trend remained when excluding seronegative subjects but was non-significant. These data underline that viral infections might impact the immunopathology of MS, but the exact link between the two entities remains subject of controversy.},
  language  = {en}
}
@article{RovitusoSchefflerWunschetal.2016,
  author    = {Rovituso, Damiano M. and Scheffler, Laura and Wunsch, Marie and Kleinschnitz, Christoph and D{\"o}rck, Sebastian and Ulzheimer, Jochen and Bayas, Antonios and Steinman, Lawrence and Erg{\"u}n, S{\"u}leyman and Kuerten, Stefanie},
  title     = {CEACAM1 mediates B cell aggregation in central nervous system autoimmunity},
  series = {Scientific Reports},
  volume    = {6},
  journal   = {Scientific Reports},
  doi       = {10.1038/srep29847},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147690},
  pages     = {29847},
  year      = {2016},
  abstract  = {B cell aggregates in the central nervous system (CNS) have been associated with rapid disease progression in patients with multiple sclerosis (MS). Here we demonstrate a key role of carcinoembryogenic antigen-related cell adhesion molecule1 (CEACAM1) in B cell aggregate formation in MS patients and a B cell-dependent mouse model of MS. CEACAM1 expression was increased on peripheral blood B cells and CEACAM1\(^+\) B cells were present in brain infiltrates of MS patients. Administration of the anti-CEACAM1 antibody T84.1 was efficient in blocking aggregation of B cells derived from MS patients. Along these lines, application of the monoclonal anti-CEACAM1 antibody mCC1 was able to inhibit CNS B cell aggregate formation and significantly attenuated established MS-like disease in mice in the absence of any adverse effects. CEACAM1 was co-expressed with the regulator molecule T cell immunoglobulin and mucin domain -3 (TIM-3) on B cells, a novel molecule that has recently been described to induce anergy in T cells. Interestingly, elevated coexpression on B cells coincided with an autoreactive T helper cell phenotype in MS patients. Overall, these data identify CEACAM1 as a clinically highly interesting target in MS pathogenesis and open new therapeutic avenues for the treatment of the disease.},
  language  = {en}
}
@article{WiegeringKorbThalheimeretal.2014,
  author    = {Wiegering, Armin and Korb, Doreen and Thalheimer, Andreas and K{\"a}mmerer, Ulrike and Allmanritter, Jan and Matthes, Niels and Linnebacher, Michael and Schlegel, Nicolas and Klein, Ingo and Erg{\"u}n, S{\"u}leyman and Germer, Christoph-Thomas and Otto, Christoph},
  title     = {E7080 (Lenvatinib), a Multi-Targeted Tyrosine Kinase Inhibitor, Demonstrates Antitumor Activities Against Colorectal Cancer Xenografts},
  doi       = {10.1016/j.neo.2014.09.008},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111165},
  year      = {2014},
  abstract  = {Clinical prognosis of metastasized colorectal carcinoma (CRC) is still not at desired levels and novel drugs are needed. Here, we focused on the multi-tyrosine kinase inhibitor E7080 (Lenvatinib) and assessed its therapeutic efficacy against human CRC cell lines in vitro and human CRC xenografts in vivo. The effect of E7080 on cell viability was examined on 10 humanCRCcell lines and humanendothelial cells (HUVEC). The inhibitory effect of E7080 on VEGF-induced angiogenesis was studied in an ex vivo mouse aortic ring angiogenesis assay. In addition, the efficacy of E7080 against xenografts derived fromCRC cell lines and CRC patient resection specimenswithmutated KRASwas investigated in vivo. Arelatively low cytotoxic effect of E7080 on CRC cell viabilitywas observed in vitro. Endothelial cells (HUVEC)weremore susceptible to the incubation with E7080. This is in line with the observation that E7080 demonstrated an anti-angiogenic effect in a three-dimensional ex vivo mouse aortic ring angiogenesis assay. E7080 effectively disrupted CRC cell-mediated VEGF-stimulated growth of HUVEC in vitro. Daily in vivo treatment with E7080 (5 mg/kg) significantly delayed the growth of KRAS mutated CRC xenografts with decreased density of tumor-associated vessel formations and without tumor regression. This observation is in line with results that E7080 did not significantly reduce the number of Ki67-positive cells in CRC xenografts. The results suggest antiangiogenic activity of E7080 at a dosage thatwas well tolerated by nudemice. E7080 may provide therapeutic benefits in the treatment of CRC with mutated KRAS.},
  language  = {en}
}
@article{KleinMeissnerKleffetal.2014,
  author    = {Klein, Diana and Meissner, Nicole and Kleff, Veronika and Jastrow, Holger and Yamaguchi, Masahiro and Erg{\"u}n, S{\"u}leyman and Jendrossek, Verena},
  title     = {Nestin(+) Tissue-Resident Multipotent Stem Cells Contribute to Tumor Progression by Differentiating into Pericytes and Smooth Muscle Cells Resulting in Blood Vessel Remodeling},
  series = {Frontiers in Oncology},
  volume    = {4},
  journal   = {Frontiers in Oncology},
  number    = {169},
  issn      = {2234-943X},
  doi       = {10.3389/fonc.2014.00169},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120973},
  year      = {2014},
  abstract  = {Tumor vessels with resistance to anti-angiogenic therapy are characterized by the normalization of the vascular structures through integration of mature pericytes and smooth muscle cells (SMC) into the vessel wall, a process termed vessel stabilization. Unfortunately, stabilization-associated vascular remodeling can result in reduced sensitivity to subsequent anti-angiogenic therapy. We show here that blockade of VEGF by bevacizumab induces stabilization of angiogenic tumor blood vessels in human tumor specimen by recruiting Nestin-positive cells, whereas mature vessels down-regulated Nestin-expression. Using xenograft tumors growing on bone-marrow (BM) chimera of C57Bl/6 wildtype and Nestin-GFP transgenic mice, we show for first time that Nestin(+) cells inducing the maturation of tumor vessels do not originate from the BM but presumably reside within the adventitia of adult blood vessels. Complementary ex vivo experiments using explants of murine aortas revealed that Nestin(+) multipotent stem cells (MPSCs) are mobilized from their niche and differentiated into pericytes and SMC through the influence of tumor-cell-secreted factors. We conclude that tissue-resident Nestin(+) cells are more relevant than BM-derived cells for vessel stabilization and therefore have to be considered in future strategies for anti-angiogenic therapy. The identification of proteins mediating recruitment or differentiation of local Nestin(+) cells with potential stem cell character to angiogenic blood vessels may allow the definition of new therapeutic targets to reduce tumor resistance against anti-angiogenic drugs.},
  language  = {en}
}
@article{KleinBenchellalKleffetal.2013,
  author    = {Klein, Diana and Benchellal, Mohamed and Kleff, Veronika and Jakob, Heinz G{\"u}nther and Erg{\"u}n, S{\"u}leyman},
  title     = {Hox genes are involved in vascular wall-resident multipotent stem cell differentiation into smooth muscle cells},
  series = {Scientific Reports},
  volume    = {3},
  journal   = {Scientific Reports},
  number    = {2178},
  doi       = {10.1038/srep02178},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131496},
  year      = {2013},
  abstract  = {Human vascular wall-resident CD44+ multipotent stem cells (VW-MPSCs) within the vascular adventitia are capable to differentiate into pericytes and smooth muscle cells (SMC). This study demonstrates HOX-dependent differentiation of CD44(+) VW-MPSCs into SMC that involves epigenetic modification of transgelin as a down-stream regulated gene. First, HOXB7, HOXC6 and HOXC8 were identified to be differentially expressed in VW-MPSCs as compared to terminal differentiated human aortic SMC, endothelial cells and undifferentiated pluripotent embryonic stem cells. Silencing these HOX genes in VW-MPSCs significantly reduced their sprouting capacity and increased expression of the SMC markers transgelin and calponin and the histone gene histone H1. Furthermore, the methylation pattern of the TAGLN promoter was altered. In summary, our findings suggest a role for certain HOX genes in regulating differentiation of human VW-MPSC into SMCs that involves epigenetic mechanisms. This is critical for understanding VW-MPSC-dependent vascular disease processes such as neointima formation and tumor vascularization.},
  language  = {en}
}
@article{BiermannHeilmannDidieetal.2012,
  author    = {Biermann, Daniel and Heilmann, Andreas and Didi{\´e}, Michael and Schlossarek, Saskia and Wahab, Azadeh and Grimm, Michael and R{\"o}mer, Maria and Reichenspurner, Hermann and Sultan, Karim R. and Steenpass, Anna and Erg{\"u}n, S{\"u}leyman and Donzelli, Sonia and Carrier, Lucie and Ehmke, Heimo and Zimmermann, Wolfram H. and Hein, Lutz and B{\"o}ger, Rainer H. and Benndorf, Ralf A.},
  title     = {Impact of AT2 Receptor Deficiency on Postnatal Cardiovascular Development},
  series = {PLoS One},
  volume    = {7},
  journal   = {PLoS One},
  number    = {10},
  doi       = {10.1371/journal.pone.0047916},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134902},
  pages     = {e47916},
  year      = {2012},
  abstract  = {Background: The angiotensin II receptor subtype 2 (AT2 receptor) is ubiquitously and highly expressed in early postnatal life. However, its role in postnatal cardiac development remained unclear. Methodology/Principal Findings: Hearts from 1, 7, 14 and 56 days old wild-type (WT) and AT2 receptor-deficient (KO) mice were extracted for histomorphometrical analysis as well as analysis of cardiac signaling and gene expression. Furthermore, heart and body weights of examined animals were recorded and echocardiographic analysis of cardiac function as well as telemetric blood pressure measurements were performed. Moreover, gene expression, sarcomere shortening and calcium transients were examined in ventricular cardiomyocytes isolated from both genotypes. KO mice exhibited an accelerated body weight gain and a reduced heart to body weight ratio as compared to WT mice in the postnatal period. However, in adult KO mice the heart to body weight ratio was significantly increased most likely due to elevated systemic blood pressure. At postnatal day 7 ventricular capillarization index and the density of \(\alpha\)-smooth muscle cell actin-positive blood vessels were higher in KO mice as compared to WT mice but normalized during adolescence. Echocardiographic assessment of cardiac systolic function at postnatal day 7 revealed decreased contractility of KO hearts in response to beta-adrenergic stimulation. Moreover, cardiomyocytes from KO mice showed a decreased sarcomere shortening and an increased peak Ca\(^{2+}\) transient in response to isoprenaline when stimulated concomitantly with angiotensin II. Conclusion: The AT2 receptor affects postnatal cardiac growth possibly via reducing body weight gain and systemic blood pressure. Moreover, it moderately attenuates postnatal vascularization of the heart and modulates the beta adrenergic response of the neonatal heart. These AT2 receptor-mediated effects may be implicated in the physiological maturation process of the heart.},
  language  = {en}
}
@article{MuturiDreesenNilewskietal.2013,
  author    = {Muturi, Harrison T. and Dreesen, Janine D. and Nilewski, Elena and Jastrow, Holger and Giebel, Bernd and Ergun, Suleyman and Singer, Berhard B.},
  title     = {Tumor and Endothelial Cell-Derived Microvesicles Carry Distinct CEACAMs and Influence T-Cell Behavior},
  series = {PLOS ONE},
  volume    = {8},
  journal   = {PLOS ONE},
  number    = {9},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0074654},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128373},
  pages     = {e74654},
  year      = {2013},
  abstract  = {Normal and malignant cells release a variety of different vesicles into their extracellular environment. The most prominent vesicles are the microvesicles (MVs, 100-1 000 nm in diameter), which are shed of the plasma membrane, and the exosomes (70-120 nm in diameter), derivates of the endosomal system. MVs have been associated with intercellular communication processes and transport numerous proteins, lipids and RNAs. As essential component of immune-escape mechanisms tumor-derived MVs suppress immune responses. Additionally, tumor-derived MVs have been found to promote metastasis, tumor-stroma interactions and angiogenesis. Since members of the carcinoembryonic antigen related cell adhesion molecule (CEACAM)-family have been associated with similar processes, we studied the distribution and function of CEACAMs in MV fractions of different human epithelial tumor cells and of human and murine endothelial cells. Here we demonstrate that in association to their cell surface phenotype, MVs released from different human epithelial tumor cells contain CEACAM1, CEACAM5 and CEACAM6, while human and murine endothelial cells were positive for CEACAM1 only. Furthermore, MVs derived from CEACAM1 transfected CHO cells carried CEACAM1. In terms of their secretion kinetics, we show that MVs are permanently released in low doses, which are extensively increased upon cellular starvation stress. Although CEACAM1 did not transmit signals into MVs it served as ligand for CEACAM expressing cell types. We gained evidence that CEACAM1-positive MVs significantly increase the CD3 and CD3/CD28-induced T-cell proliferation. All together, our data demonstrate that MV-bound forms of CEACAMs play important roles in intercellular communication processes, which can modulate immune response, tumor progression, metastasis and angiogenesis.},
  language  = {en}
}
@article{RajendranBoettigerDentzienetal.2021,
  author    = {Rajendran, Ranjithkumar and B{\"o}ttiger, Gregor and Dentzien, Niklas and Rajendran, Vinothkumar and Sharifi, Bischand and Erg{\"u}n, S{\"u}leyman and Stadelmann, Christine and Karnati, Srikanth and Berghoff, Martin},
  title     = {Effects of FGFR tyrosine kinase inhibition in OLN-93 oligodendrocytes},
  series = {Cells},
  volume    = {10},
  journal   = {Cells},
  number    = {6},
  issn      = {2073-4409},
  doi       = {10.3390/cells10061318},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239600},
  year      = {2021},
  abstract  = {Fibroblast growth factor (FGF) signaling is involved in the pathogenesis of multiple sclerosis (MS). Data from neuropathology studies suggest that FGF signaling contributes to the failure of remyelination in MS. In MOG\(_{35-55}\)-induced EAE, oligodendrocyte-specific deletion of FGFR1 and FGFR2 resulted in a less severe disease course, reduced inflammation, myelin and axon degeneration and changed FGF/FGFR and BDNF/TrkB signaling. Since signaling cascades in oligodendrocytes could not be investigated in the EAE studies, we here aimed to characterize FGFR-dependent oligodendrocyte-specific signaling in vitro. FGFR inhibition was achieved by application of the multi-kinase-inhibitor dovitinib and the FGFR1/2/3-inhibitor AZD4547. Both substances are potent inhibitors of FGF signaling; they are effective in experimental tumor models and patients with malignancies. Effects of FGFR inhibition in oligodendrocytes were studied by immunofluorescence microscopy, protein and gene analyses. Application of the tyrosine kinase inhibitors reduced FGFR1, phosphorylated ERK and Akt expression, and it enhanced BDNF and TrkB expression. Furthermore, the myelin proteins CNPase and PLP were upregulated by FGFR inhibition. In summary, inhibition of FGFR signaling in oligodendrocytes can be achieved by application of tyrosine kinase inhibitors. Decreased phosphorylation of ERK and Akt is associated with an upregulation of BDNF/TrkB signaling, which may be responsible for the increased production of myelin proteins. Furthermore, these data suggest that application of FGFR inhibitors may have the potential to promote remyelination in the CNS.},
  language  = {en}
}
@article{WernerWakabayashiBaueretal.2018,
  author    = {Werner, Rudolf and Wakabayashi, Hiroshi and Bauer, Jochen and Sch{\"u}tz, Claudia and Zechmeister, Christina and Hayakawa, Nobuyuki and Javadi, Mehrbod S. and Lapa, Constantin and Jahns, Roland and Erg{\"u}n, S{\"u}leyman and Jahns, Valerie and Higuchi, Takahiro},
  title     = {Longitudinal \(^{18}\)F-FDG PET imaging in a Rat Model of Autoimmune Myocarditis},
  series = {European Heart Journal Cardiovascular Imaging},
  journal   = {European Heart Journal Cardiovascular Imaging},
  issn      = {2047-2404},
  doi       = {10.1093/ehjci/jey119},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165601},
  pages     = {1-8},
  year      = {2018},
  abstract  = {Aims: Although mortality rate is very high, diagnosis of acute myocarditis remains challenging with conventional tests. We aimed to elucidate the potential role of longitudinal 2-Deoxy-2-\(^{18}\)F-fluoro-D-glucose (\(^{18}\)F-FDG) positron emission tomography (PET) inflammation monitoring in a rat model of experimental autoimmune myocarditis. Methods and results: Autoimmune myocarditis was induced in Lewis rats by immunizing with porcine cardiac myosin emulsified in complete Freund's adjuvant. Time course of disease was assessed by longitudinal \(^{18}\)F-FDG PET imaging. A correlative analysis between in- and ex vivo \(^{18}\)F-FDG signalling and macrophage infiltration using CD68 staining was conducted. Finally, immunohistochemistry analysis of the cell-adhesion markers CD34 and CD44 was performed at different disease stages determined by longitudinal \(^{18}\)F-FDG PET imaging. After immunization, myocarditis rats revealed a temporal increase in 18F-FDG uptake (peaked at week 3), which was followed by a rapid decline thereafter. Localization of CD68 positive cells was well correlated with in vivo \(^{18}\)F-FDG PET signalling (R\(^2\) = 0.92) as well as with ex vivo 18F-FDG autoradiography (R\(^2\) = 0.9, P < 0.001, respectively). CD44 positivity was primarily observed at tissue samples obtained at acute phase (i.e. at peak 18F-FDG uptake), while CD34-positive staining areas were predominantly identified in samples harvested at both sub-acute and chronic phases (i.e. at \(^{18}\)F-FDG decrease). Conclusion: \(^{18}\)F-FDG PET imaging can provide non-invasive serial monitoring of cardiac inflammation in a rat model of acute myocarditis.},
  subject      = {Myokarditis},
  language  = {en}
}
@article{SchuetzeRoehringVorlovaetal.2015,
  author    = {Sch{\"u}tze, Friedrich and R{\"o}hring, Florian and Vorlov{\´a}, Sandra and G{\"a}tzner, Sabine and Kuhn, Anja and Erg{\"u}n, S{\"u}leyman and Henke, Erik},
  title     = {Inhibition of lysyl oxidases improves drug diffusion and increases efficacy of cytotoxic treatment in 3D tumor models},
  series = {Scientific Reports},
  volume    = {5},
  journal   = {Scientific Reports},
  number    = {17576},
  doi       = {10.1038/srep17576},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-145109},
  year      = {2015},
  abstract  = {Tumors are characterized by a rigid, highly cross-linked extracellular matrix (ECM), which impedes homogeneous drug distribution and potentially protects malignant cells from exposure to therapeutics. Lysyl oxidases are major contributors to tissue stiffness and the elevated expression of these enzymes observed in most cancers might influence drug distribution and efficacy. We examined the effect of lysyl oxidases on drug distribution and efficacy in 3D in vitro assay systems. In our experiments elevated lysyl oxidase activity was responsible for reduced drug diffusion under hypoxic conditions and consequently impaired cytotoxicity of various chemotherapeutics. This effect was only observed in 3D settings but not in 2D-cell culture, confirming that lysyl oxidases affect drug efficacy by modification of the ECM and do not confer a direct desensitizing effect. Both drug diffusion and efficacy were strongly enhanced by inhibition of lysyl oxidases. The results from the in vitro experiments correlated with tumor drug distribution in vivo, and predicted response to therapeutics in murine tumor models. Our results demonstrate that lysyl oxidase activity modulates the physical barrier function of ECM for small molecule drugs influencing their therapeutic efficacy. Targeting this process has the potential to significantly enhance therapeutic efficacy in the treatment of malignant diseases.},
  language  = {en}
}
@article{HorderGuazaLasherasGrummeletal.2021,
  author    = {Horder, Hannes and Guaza Lasheras, Mar and Grummel, Nadine and Nadernezhad, Ali and Herbig, Johannes and Erg{\"u}n, S{\"u}leyman and Teßmar, J{\"o}rg and Groll, J{\"u}rgen and Fabry, Ben and Bauer-Kreisel, Petra and Blunk, Torsten},
  title     = {Bioprinting and differentiation of adipose-derived stromal cell spheroids for a 3D breast cancer-adipose tissue model},
  series = {Cells},
  volume    = {10},
  journal   = {Cells},
  number    = {4},
  doi       = {10.3390/cells10040803},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236496},
  year      = {2021},
  abstract  = {Biofabrication, including printing technologies, has emerged as a powerful approach to the design of disease models, such as in cancer research. In breast cancer, adipose tissue has been acknowledged as an important part of the tumor microenvironment favoring tumor progression. Therefore, in this study, a 3D-printed breast cancer model for facilitating investigations into cancer cell-adipocyte interaction was developed. First, we focused on the printability of human adipose-derived stromal cell (ASC) spheroids in an extrusion-based bioprinting setup and the adipogenic differentiation within printed spheroids into adipose microtissues. The printing process was optimized in terms of spheroid viability and homogeneous spheroid distribution in a hyaluronic acid-based bioink. Adipogenic differentiation after printing was demonstrated by lipid accumulation, expression of adipogenic marker genes, and an adipogenic ECM profile. Subsequently, a breast cancer cell (MDA-MB-231) compartment was printed onto the adipose tissue constructs. After nine days of co-culture, we observed a cancer cell-induced reduction of the lipid content and a remodeling of the ECM within the adipose tissues, with increased fibronectin, collagen I and collagen VI expression. Together, our data demonstrate that 3D-printed breast cancer-adipose tissue models can recapitulate important aspects of the complex cell-cell and cell-matrix interplay within the tumor-stroma microenvironment},
  language  = {en}
}
@article{KleefeldtBoemmelBroedeetal.2019,
  author    = {Kleefeldt, Florian and B{\"o}mmel, Heike and Broede, Britta and Thomsen, Michael and Pfeiffer, Verena and W{\"o}rsd{\"o}rfer, Philipp and Karnati, Srikanth and Wagner, Nicole and Rueckschloss, Uwe and Erg{\"u}n, S{\"u}leyman},
  title     = {Aging-related carcinoembryonic antigen-related cell adhesion molecule 1 signaling promotes vascular dysfunction},
  series = {Aging Cell},
  volume    = {2019},
  journal   = {Aging Cell},
  number    = {18},
  doi       = {10.1111/acel.13025},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201231},
  pages     = {e13025},
  year      = {2019},
  abstract  = {Aging is an independent risk factor for cardiovascular diseases and therefore of particular interest for the prevention of cardiovascular events. However, the mechanisms underlying vascular aging are not well understood. Since carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is crucially involved in vascular homeostasis, we sought to identify the role of CEACAM1 in vascular aging. Using human internal thoracic artery and murine aorta, we show that CEACAM1 is upregulated in the course of vascular aging. Further analyses demonstrated that TNF-α is CEACAM1-dependently upregulated in the aging vasculature. Vice versa, TNF-α induces CEACAM1 expression. This results in a feed-forward loop in the aging vasculature that maintains a chronic pro-inflammatory milieu. Furthermore, we demonstrate that age-associated vascular alterations, that is, increased oxidative stress and vascular fibrosis, due to increased medial collagen deposition crucially depend on the presence of CEACAM1. Additionally, age-dependent upregulation of vascular CEACAM1 expression contributes to endothelial barrier impairment, putatively via increased VEGF/VEGFR-2 signaling. Consequently, aging-related upregulation of vascular CEACAM1 expression results in endothelial dysfunction that may promote atherosclerotic plaque formation in the presence of additional risk factors. Our data suggest that CEACAM1 might represent an attractive target in order to delay physiological aging and therefore the transition to vascular disorders such as atherosclerosis.},
  language  = {en}
}
@article{JordanJaeckleScheidtetal.2021,
  author    = {Jordan, Martin C. and J{\"a}ckle, Veronika and Scheidt, Sebastian and Gilbert, Fabian and H{\"o}lscher-Doht, Stefanie and Erg{\"u}n, S{\"u}leyman and Meffert, Rainer H. and Heintel, Timo M.},
  title     = {Trans-obturator cable fixation of open book pelvic injuries},
  series = {Scientific Reports},
  volume    = {11},
  journal   = {Scientific Reports},
  number    = {1},
  doi       = {10.1038/s41598-021-92755-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261212},
  year      = {2021},
  abstract  = {Operative treatment of ruptured pubic symphysis by plating is often accompanied by complications. Trans-obturator cable fixation might be a more reliable technique; however, have not yet been tested for stabilization of ruptured pubic symphysis. This study compares symphyseal trans-obturator cable fixation versus plating through biomechanical testing and evaluates safety in a cadaver experiment. APC type II injuries were generated in synthetic pelvic models and subsequently separated into three different groups. The anterior pelvic ring was fixed using a four-hole steel plate in Group A, a stainless steel cable in Group B, and a titan band in Group C. Biomechanical testing was conducted by a single-leg-stance model using a material testing machine under physiological load levels. A cadaver study was carried out to analyze the trans-obturator surgical approach. Peak-to-peak displacement, total displacement, plastic deformation and stiffness revealed a tendency for higher stability for trans-obturator cable/band fixation but no statistical difference to plating was detected. The cadaver study revealed a safe zone for cable passage with sufficient distance to the obturator canal. Trans-obturator cable fixation has the potential to become an alternative for symphyseal fixation with less complications.},
  language  = {en}
}
@article{JordanBroeerFischeretal.2022,
  author    = {Jordan, Martin C. and Br{\"o}er, David and Fischer, Christian and Heilig, Philipp and Gilbert, Fabian and H{\"o}lscher-Doht, Stefanie and Kalogirou, Charis and Popp, Kevin and Grunz, Jan-Peter and Huflage, Henner and Jakubietz, Rafael G. and Erg{\"u}n, S{\"u}leyman and Meffert, Rainer H.},
  title     = {Development and preclinical evaluation of a cable-clamp fixation device for a disrupted pubic symphysis},
  series = {Communications Medicine},
  volume    = {2},
  journal   = {Communications Medicine},
  number    = {1},
  doi       = {10.1038/s43856-022-00227-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-299800},
  year      = {2022},
  abstract  = {Background Traumatic separation of the pubic symphysis can destabilize the pelvis and require surgical fixation to reduce symphyseal gapping. The traditional approach involves open reduction and the implantation of a steel symphyseal plate (SP) on the pubic bone to hold the reposition. Despite its widespread use, SP-fixation is often associated with implant failure caused by screw loosening or breakage. Methods To address the need for a more reliable surgical intervention, we developed and tested two titanium cable-clamp implants. The cable served as tensioning device while the clamp secured the cable to the bone. The first implant design included a steel cable anterior to the pubic symphysis to simplify its placement outside the pelvis, and the second design included a cable encircling the pubic symphysis to stabilize the anterior pelvic ring. Using highly reproducible synthetic bone models and a limited number of cadaver specimens, we performed a comprehensive biomechanical study of implant stability and evaluated surgical feasibility. Results We were able to demonstrate that the cable-clamp implants provide stability equivalent to that of a traditional SP-fixation but without the same risks of implant failure. We also provide detailed ex vivo evaluations of the safety and feasibility of a trans-obturator surgical approach required for those kind of fixation. Conclusion We propose that the developed cable-clamp fixation devices may be of clinical value in treating pubic symphysis separation.},
  language  = {en}
}
@article{HenkeNandigamaErguen2020,
  author    = {Henke, Erik and Nandigama, Rajender and Erg{\"u}n, S{\"u}leyman},
  title     = {Extracellular matrix in the tumor microenvironment and its impact on cancer therapy},
  series = {Frontiers in Molecular Biosciences},
  volume    = {6},
  journal   = {Frontiers in Molecular Biosciences},
  number    = {160},
  issn      = {2296-889X},
  doi       = {10.3389/fmolb.2019.00160},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-199341},
  year      = {2020},
  abstract  = {Solid tumors are complex organ-like structures that consist not only of tumor cells but also of vasculature, extracellular matrix (ECM), stromal, and immune cells. Often, this tumor microenvironment (TME) comprises the larger part of the overall tumor mass. Like the other components of the TME, the ECM in solid tumors differs significantly from that in normal organs. Intratumoral signaling, transport mechanisms, metabolisms, oxygenation, and immunogenicity are strongly affected if not controlled by the ECM. Exerting this regulatory control, the ECM does not only influence malignancy and growth of the tumor but also its response toward therapy. Understanding the particularities of the ECM in solid tumor is necessary to develop approaches to interfere with its negative effect. In this review, we will also highlight the current understanding of the physical, cellular, and molecular mechanisms by which the pathological tumor ECM affects the efficiency of radio-, chemo-, and immunotherapy. Finally, we will discuss the various strategies to target and modify the tumor ECM and how they could be utilized to improve response to therapy.},
  language  = {en}
}
@article{KleefeldtUpcinBoemmeletal.2022,
  author    = {Kleefeldt, Florian and Upcin, Berin and B{\"o}mmel, Heike and Schulz, Christian and Eckner, Georg and Allmanritter, Jan and Bauer, Jochen and Braunger, Barbara and Rueckschloss, Uwe and Erg{\"u}n, S{\"u}leyman},
  title     = {Bone marrow-independent adventitial macrophage progenitor cells contribute to angiogenesis},
  series = {Cell Death \& Disease},
  volume    = {13},
  journal   = {Cell Death \& Disease},
  number    = {3},
  doi       = {10.1038/s41419-022-04605-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-299724},
  year      = {2022},
  abstract  = {Pathological angiogenesis promotes tumor growth, metastasis, and atherosclerotic plaque rupture. Macrophages are key players in these processes. However, whether these macrophages differentiate from bone marrow-derived monocytes or from local vascular wall-resident stem and progenitor cells (VW-SCs) is an unresolved issue of angiogenesis. To answer this question, we analyzed vascular sprouting and alterations in aortic cell populations in mouse aortic ring assays (ARA). ARA culture leads to the generation of large numbers of macrophages, especially within the aortic adventitia. Using immunohistochemical fate-mapping and genetic in vivo-labeling approaches we show that 60\% of these macrophages differentiate from bone marrow-independent Ly6c\(^{+}\)/Sca-1\(^{+}\) adventitial progenitor cells. Analysis of the NCX\(^{-/-}\) mouse model that genetically lacks embryonic circulation and yolk sac perfusion indicates that at least some of those progenitor cells arise yolk sac-independent. Macrophages represent the main source of VEGF in ARA that vice versa promotes the generation of additional macrophages thereby creating a pro-angiogenetic feedforward loop. Additionally, macrophage-derived VEGF activates CD34\(^{+}\) progenitor cells within the adventitial vasculogenic zone to differentiate into CD31\(^{+}\) endothelial cells. Consequently, depletion of macrophages and VEGFR2 antagonism drastically reduce vascular sprouting activity in ARA. In summary, we show that angiogenic activation induces differentiation of macrophages from bone marrow-derived as well as from bone marrow-independent VW-SCs. The latter ones are at least partially yolk sac-independent, too. Those VW-SC-derived macrophages critically contribute to angiogenesis, making them an attractive target to interfere with pathological angiogenesis in cancer and atherosclerosis as well as with regenerative angiogenesis in ischemic cardiovascular disorders.},
  language  = {en}
}
@article{KarnatiSeimetzKleefeldtetal.2021,
  author    = {Karnati, Srikanth and Seimetz, Michael and Kleefeldt, Florian and Sonawane, Avinash and Madhusudhan, Thati and Bachhuka, Akash and Kosanovic, Djuro and Weissmann, Norbert and Kr{\"u}ger, Karsten and Erg{\"u}n, S{\"u}leyman},
  title     = {Chronic Obstructive Pulmonary Disease and the Cardiovascular System: Vascular Repair and Regeneration as a Therapeutic Target},
  series = {Frontiers in Cardiovascular Medicine},
  volume    = {8},
  journal   = {Frontiers in Cardiovascular Medicine},
  issn      = {2297-055X},
  doi       = {10.3389/fcvm.2021.649512},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235631},
  year      = {2021},
  abstract  = {Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide and encompasses chronic bronchitis and emphysema. It has been shown that vascular wall remodeling and pulmonary hypertension (PH) can occur not only in patients with COPD but also in smokers with normal lung function, suggesting a causal role for vascular alterations in the development of emphysema. Mechanistically, abnormalities in the vasculature, such as inflammation, endothelial dysfunction, imbalances in cellular apoptosis/proliferation, and increased oxidative/nitrosative stress promote development of PH, cor pulmonale, and most probably pulmonary emphysema. Hypoxemia in the pulmonary chamber modulates the activation of key transcription factors and signaling cascades, which propagates inflammation and infiltration of neutrophils, resulting in vascular remodeling. Endothelial progenitor cells have angiogenesis capabilities, resulting in transdifferentiation of the smooth muscle cells via aberrant activation of several cytokines, growth factors, and chemokines. The vascular endothelium influences the balance between vaso-constriction and -dilation in the heart. Targeting key players affecting the vasculature might help in the development of new treatment strategies for both PH and COPD. The present review aims to summarize current knowledge about vascular alterations and production of reactive oxygen species in COPD. The present review emphasizes on the importance of the vasculature for the usually parenchyma-focused view of the pathobiology of COPD.},
  language  = {en}
}
@article{DoganScheuringWagneretal.2021,
  author    = {Dogan, Leyla and Scheuring, Ruben and Wagner, Nicole and Ueda, Yuichiro and Schmidt, Sven and W{\"o}rsd{\"o}rfer, Philipp and Groll, J{\"u}rgen and Erg{\"u}n, S{\"u}leyman},
  title     = {Human iPSC-derived mesodermal progenitor cells preserve their vasculogenesis potential after extrusion and form hierarchically organized blood vessels},
  series = {Biofabrication},
  volume    = {13},
  journal   = {Biofabrication},
  number    = {4},
  doi       = {10.1088/1758-5090/ac26ac},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-254046},
  year      = {2021},
  abstract  = {Post-fabrication formation of a proper vasculature remains an unresolved challenge in bioprinting. Established strategies focus on the supply of the fabricated structure with nutrients and oxygen and either rely on the mere formation of a channel system using fugitive inks or additionally use mature endothelial cells and/or peri-endothelial cells such as smooth muscle cells for the formation of blood vessels in vitro. Functional vessels, however, exhibit a hierarchical organization and multilayered wall structure that is important for their function. Human induced pluripotent stem cell-derived mesodermal progenitor cells (hiMPCs) have been shown to possess the capacity to form blood vessels in vitro, but have so far not been assessed for their applicability in bioprinting processes. Here, we demonstrate that hiMPCs, after formulation into an alginate/collagen type I bioink and subsequent extrusion, retain their ability to give rise to the formation of complex vessels that display a hierarchical network in a process that mimics the embryonic steps of vessel formation during vasculogenesis. Histological evaluations at different time points of extrusion revealed the initial formation of spheres, followed by lumen formation and further structural maturation as evidenced by building a multilayered vessel wall and a vascular network. These findings are supported by immunostainings for endothelial and peri-endothelial cell markers as well as electron microscopic analyses at the ultrastructural level. Moreover, endothelial cells in capillary-like vessel structures deposited a basement membrane-like matrix at the basal side between the vessel wall and the alginate-collagen matrix. After transplantation of the printed constructs into the chicken chorioallantoic membrane (CAM) the printed vessels connected to the CAM blood vessels and get perfused in vivo. These results evidence the applicability and great potential of hiMPCs for the bioprinting of vascular structures mimicking the basic morphogenetic steps of de novo vessel formation during embryogenesis.},
  language  = {en}
}
@article{LuetkensErguenHuflageetal.2021,
  author    = {Luetkens, Karsten Sebastian and Erg{\"u}n, S{\"u}leyman and Huflage, Henner and Kunz, Andreas Steven and Gietzen, Carsten Herbert and Conrads, Nora and Pennig, Lenhard and Goertz, Lukas and Bley, Thorsten Alexander and Gassenmaier, Tobias and Grunz, Jan-Peter},
  title     = {Dose reduction potential in cone-beam CT imaging of upper extremity joints with a twin robotic x-ray system},
  series = {Scientific Reports},
  volume    = {11},
  journal   = {Scientific Reports},
  number    = {1},
  doi       = {10.1038/s41598-021-99748-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-270429},
  year      = {2021},
  abstract  = {Cone-beam computed tomography is a powerful tool for 3D imaging of the appendicular skeleton, facilitating detailed visualization of bone microarchitecture. This study evaluated various combinations of acquisition and reconstruction parameters for the cone-beam CT mode of a twin robotic x-ray system in cadaveric wrist and elbow scans, aiming to define the best possible trade-off between image quality and radiation dose. Images were acquired with different combinations of tube voltage and tube current-time product, resulting in five scan protocols with varying volume CT dose indices: full-dose (FD; 17.4 mGy), low-dose (LD; 4.5 mGy), ultra-low-dose (ULD; 1.15 mGy), modulated low-dose (mLD; 0.6 mGy) and modulated ultra-low-dose (mULD; 0.29 mGy). Each set of projection data was reconstructed with three convolution kernels (very sharp [Ur77], sharp [Br69], intermediate [Br62]). Five radiologists subjectively assessed the image quality of cortical bone, cancellous bone and soft tissue using seven-point scales. Irrespective of the reconstruction kernel, overall image quality of every FD, LD and ULD scan was deemed suitable for diagnostic use in contrast to mLD (very sharp/sharp/intermediate: 60/55/70\%) and mULD (0/3/5\%). Superior depiction of cortical and cancellous bone was achieved in FD\(_{Ur77}\) and LD\(_{Ur77}\) examinations (p < 0.001) with LD\(_{Ur77}\) scans also providing favorable bone visualization compared to FD\(_{Br69}\) and FD\(_{Br62}\) (p < 0.001). Fleiss' kappa was 0.618 (0.594-0.641; p < 0.001), indicating substantial interrater reliability. In this study, we demonstrate that considerable dose reduction can be realized while maintaining diagnostic image quality in upper extremity joint scans with the cone-beam CT mode of a twin robotic x-ray system. Application of sharper convolution kernels for image reconstruction facilitates superior display of bone microarchitecture.},
  language  = {en}
}
@article{GrunzWenigKunzetal.2020,
  author    = {Grunz, Jan-Peter and Wenig, Andreas Max and Kunz, Andreas Steven and Veyhl-Wichmann, Maike and Schmitt, Rainer and Gietzen, Carsten Herbert and Pennig, Lenhard and Herz, Stefan and Erg{\"u}n, S{\"u}leyman and Bley, Thorsten Alexander and Gassenmaier, Tobias},
  title     = {3D cone-beam CT with a twin robotic x-ray system in elbow imaging: comparison of image quality to high-resolution multidetector CT},
  series = {European Radiology Experimental},
  volume    = {4},
  journal   = {European Radiology Experimental},
  doi       = {10.1186/s41747-020-00177-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229877},
  year      = {2020},
  abstract  = {Background Elbow imaging is challenging with conventional multidetector computed tomography (MDCT), while cone-beam CT (CBCT) provides superior options. We compared intra-individually CBCT versus MDCT image quality in cadaveric elbows. Methods A twin robotic x-ray system with new CBCT mode and a high-resolution clinical MDCT were compared in 16 cadaveric elbows. Both systems were operated with a dedicated low-dose (LD) protocol (equivalent volume CT dose index [CTDI\(_{vol(16 cm)}\)] = 3.3 mGy) and a regular clinical scan dose (RD) protocol (CTDI\(_{vol(16 cm)}\) = 13.8 mGy). Image quality was evaluated by two radiologists (R1 and R2) on a seven-point Likert scale, and estimation of signal intensity in cancellous bone was conducted. Wilcoxon signed-rank tests and intraclass correlation coefficient (ICC) statistics were used. Results The CBCT prototype provided superior subjective image quality compared to MDCT scans (for RD, p ≤ 0.004; for LD, p ≤ 0.001). Image quality was rated very good or excellent in 100\% of the cases by both readers for RD CBCT, 100\% (R1) and 93.8\% (R2) for LD CBCT, 62.6\% and 43.8\% for RD MDCT, and 0.0\% and 0.0\% for LD MDCT. Single-measure ICC was 0.95 (95\% confidence interval 0.91-0.97; p < 0.001). Software-based assessment supported subjective findings with less "undecided" pixels in CBCT than dose-equivalent MDCT (p < 0.001). No significant difference was found between LD CBCT and RD MDCT. Conclusions In cadaveric elbow studies, the tested cone-beam CT prototype delivered superior image quality compared to high-end multidetector CT and showed a potential for considerable dose reduction.},
  language  = {en}
}
@article{BielmeierSchmittKleefeldtetal.2022,
  author    = {Bielmeier, Christina B. and Schmitt, Sabrina I. and Kleefeldt, Nikolai and Boneva, Stefaniya K. and Schlecht, Anja and Vallon, Mario and Tamm, Ernst R. and Hillenkamp, Jost and Erg{\"u}n, S{\"u}leyman and Neueder, Andreas and Braunger, Barbara M.},
  title     = {Deficiency in retinal TGFβ signaling aggravates neurodegeneration by modulating pro-apoptotic and MAP kinase pathways},
  series = {International Journal of Molecular Sciences},
  volume    = {23},
  journal   = {International Journal of Molecular Sciences},
  number    = {5},
  issn      = {1422-0067},
  doi       = {10.3390/ijms23052626},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-283971},
  year      = {2022},
  abstract  = {Transforming growth factor β (TGFβ) signaling has manifold functions such as regulation of cell growth, differentiation, migration, and apoptosis. Moreover, there is increasing evidence that it also acts in a neuroprotective manner. We recently showed that TGFβ receptor type 2 (Tgfbr2) is upregulated in retinal neurons and M{\"u}ller cells during retinal degeneration. In this study we investigated if this upregulation of TGFβ signaling would have functional consequences in protecting retinal neurons. To this end, we analyzed the impact of TGFβ signaling on photoreceptor viability using mice with cell type-specific deletion of Tgfbr2 in retinal neurons and M{\"u}ller cells (Tgfbr2\(_{ΔOC}\)) in combination with a genetic model of photoreceptor degeneration (VPP). We examined retinal morphology and the degree of photoreceptor degeneration, as well as alterations of the retinal transcriptome. In summary, retinal morphology was not altered due to TGFβ signaling deficiency. In contrast, VPP-induced photoreceptor degeneration was drastically exacerbated in double mutant mice (Tgfbr2\(_{ΔOC}\); VPP) by induction of pro-apoptotic genes and dysregulation of the MAP kinase pathway. Therefore, TGFβ signaling in retinal neurons and M{\"u}ller cells exhibits a neuroprotective effect and might pose promising therapeutic options to attenuate photoreceptor degeneration in humans.},
  language  = {en}
}
@article{RossowVeitlVorlovaetal.2018,
  author    = {Rossow, Leonie and Veitl, Simona and Vorlov{\´a}, Sandra and Wax, Jacqueline K. and Kuhn, Anja E. and Maltzahn, Verena and Upcin, Berin and Karl, Franziska and Hoffmann, Helene and G{\"a}tzner, Sabine and Kallius, Matthias and Nandigama, Rajender and Scheld, Daniela and Irmak, Ster and Herterich, Sabine and Zernecke, Alma and Erg{\"u}n, S{\"u}leyman and Henke, Erik},
  title     = {LOX-catalyzed collagen stabilization is a proximal cause for intrinsic resistance to chemotherapy},
  series = {Oncogene},
  volume    = {37},
  journal   = {Oncogene},
  doi       = {10.1038/s41388-018-0320-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-227008},
  pages     = {4921-4940},
  year      = {2018},
  abstract  = {The potential of altering the tumor ECM to improve drug response remains fairly unexplored. To identify targets for modification of the ECM aiming to improve drug response and overcome resistance, we analyzed expression data sets from pre-treatment patient cohorts. Cross-evaluation identified a subset of chemoresistant tumors characterized by increased expression of collagens and collagen-stabilizing enzymes. We demonstrate that strong collagen expression and stabilization sets off a vicious circle of self-propagating hypoxia, malignant signaling, and aberrant angiogenesis that can be broken by an appropriate auxiliary intervention: Interfering with collagen stabilization by inhibition of lysyl oxidases significantly enhanced response to chemotherapy in various tumor models, even in metastatic disease. Inhibition of collagen stabilization by itself can reduce or enhance tumor growth depending on the tumor type. The mechanistical basis for this behavior is the dependence of the individual tumor on nutritional supply on one hand and on high tissue stiffness for FAK signaling on the other.},
  language  = {en}
}
@article{MeyerWatermannDreyeretal.2021,
  author    = {Meyer, Malin Tordis and Watermann, Christoph and Dreyer, Thomas and Wagner, Steffen and Wittekindt, Claus and Klussmann, Jens Peter and Erg{\"u}n, S{\"u}leyman and Baumgart-Vogt, Eveline and Karnati, Srikanth},
  title     = {Differential expression of peroxisomal proteins in distinct types of parotid gland tumors},
  series = {International Journal of Molecular Sciences},
  volume    = {22},
  journal   = {International Journal of Molecular Sciences},
  number    = {15},
  issn      = {1422-0067},
  doi       = {10.3390/ijms22157872},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261047},
  year      = {2021},
  abstract  = {Salivary gland cancers are rare but aggressive tumors that have poor prognosis and lack effective cure. Of those, parotid tumors constitute the majority. Functioning as metabolic machinery contributing to cellular redox balance, peroxisomes have emerged as crucial players in tumorigenesis. Studies on murine and human cells have examined the role of peroxisomes in carcinogenesis with conflicting results. These studies either examined the consequences of altered peroxisomal proliferators or compared their expression in healthy and neoplastic tissues. None, however, examined such differences exclusively in human parotid tissue or extended comparison to peroxisomal proteins and their associated gene expressions. Therefore, we examined differences in peroxisomal dynamics in parotid tumors of different morphologies. Using immunofluorescence and quantitative PCR, we compared the expression levels of key peroxisomal enzymes and proliferators in healthy and neoplastic parotid tissue samples. Three parotid tumor subtypes were examined: pleomorphic adenoma, mucoepidermoid carcinoma and acinic cell carcinoma. We observed higher expression of peroxisomal matrix proteins in neoplastic samples with exceptional down regulation of certain enzymes; however, the degree of expression varied between tumor subtypes. Our findings confirm previous experimental results on other organ tissues and suggest peroxisomes as possible therapeutic targets or markers in all or certain subtypes of parotid neoplasms.},
  language  = {en}
}
@article{SchlechtVallonWagneretal.2021,
  author    = {Schlecht, Anja and Vallon, Mario and Wagner, Nicole and Erg{\"u}n, S{\"u}leyman and Braunger, Barbara M.},
  title     = {TGFβ-Neurotrophin Interactions in Heart, Retina, and Brain},
  series = {Biomolecules},
  volume    = {11},
  journal   = {Biomolecules},
  number    = {9},
  issn      = {2218-273X},
  doi       = {10.3390/biom11091360},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246159},
  year      = {2021},
  abstract  = {Ischemic insults to the heart and brain, i.e., myocardial and cerebral infarction, respectively, are amongst the leading causes of death worldwide. While there are therapeutic options to allow reperfusion of ischemic myocardial and brain tissue by reopening obstructed vessels, mitigating primary tissue damage, post-infarction inflammation and tissue remodeling can lead to secondary tissue damage. Similarly, ischemia in retinal tissue is the driving force in the progression of neovascular eye diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD), which eventually lead to functional blindness, if left untreated. Intriguingly, the easily observable retinal blood vessels can be used as a window to the heart and brain to allow judgement of microvascular damages in diseases such as diabetes or hypertension. The complex neuronal and endocrine interactions between heart, retina and brain have also been appreciated in myocardial infarction, ischemic stroke, and retinal diseases. To describe the intimate relationship between the individual tissues, we use the terms heart-brain and brain-retina axis in this review and focus on the role of transforming growth factor β (TGFβ) and neurotrophins in regulation of these axes under physiologic and pathologic conditions. Moreover, we particularly discuss their roles in inflammation and repair following ischemic/neovascular insults. As there is evidence that TGFβ signaling has the potential to regulate expression of neurotrophins, it is tempting to speculate, and is discussed here, that cross-talk between TGFβ and neurotrophin signaling protects cells from harmful and/or damaging events in the heart, retina, and brain.},
  language  = {en}
}
@article{LiuHanBlairetal.2021,
  author    = {Liu, Fengming and Han, Kun and Blair, Robert and Kenst, Kornelia and Qin, Zhongnan and Upcin, Berin and W{\"o}rsd{\"o}rfer, Philipp and Midkiff, Cecily C. and Mudd, Joseph and Belyaeva, Elizaveta and Milligan, Nicholas S. and Rorison, Tyler D. and Wagner, Nicole and Bodem, Jochen and D{\"o}lken, Lars and Aktas, Bertal H. and Vander Heide, Richard S. and Yin, Xiao-Ming and Kolls, Jay K. and Roy, Chad J. and Rappaport, Jay and Erg{\"u}n, S{\"u}leyman and Qin, Xuebin},
  title     = {SARS-CoV-2 Infects Endothelial Cells In Vivo and In Vitro},
  series = {Frontiers in Cellular and Infection Microbiology},
  volume    = {11},
  journal   = {Frontiers in Cellular and Infection Microbiology},
  issn      = {2235-2988},
  doi       = {10.3389/fcimb.2021.701278},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241948},
  year      = {2021},
  abstract  = {SARS-CoV-2 infection can cause fatal inflammatory lung pathology, including thrombosis and increased pulmonary vascular permeability leading to edema and hemorrhage. In addition to the lung, cytokine storm-induced inflammatory cascade also affects other organs. SARS-CoV-2 infection-related vascular inflammation is characterized by endotheliopathy in the lung and other organs. Whether SARS-CoV-2 causes endotheliopathy by directly infecting endothelial cells is not known and is the focus of the present study. We observed 1) the co-localization of SARS-CoV-2 with the endothelial cell marker CD31 in the lungs of SARS-CoV-2-infected mice expressing hACE2 in the lung by intranasal delivery of adenovirus 5-hACE2 (Ad5-hACE2 mice) and non-human primates at both the protein and RNA levels, and 2) SARS-CoV-2 proteins in endothelial cells by immunogold labeling and electron microscopic analysis. We also detected the co-localization of SARS-CoV-2 with CD31 in autopsied lung tissue obtained from patients who died from severe COVID-19. Comparative analysis of RNA sequencing data of the lungs of infected Ad5-hACE2 and Ad5-empty (control) mice revealed upregulated KRAS signaling pathway, a well-known pathway for cellular activation and dysfunction. Further, we showed that SARS-CoV-2 directly infects mature mouse aortic endothelial cells (AoECs) that were activated by performing an aortic sprouting assay prior to exposure to SARS-CoV-2. This was demonstrated by co-localization of SARS-CoV-2 and CD34 by immunostaining and detection of viral particles in electron microscopic studies. Moreover, the activated AoECs became positive for ACE-2 but not quiescent AoECs. Together, our results indicate that in addition to pneumocytes, SARS-CoV-2 also directly infects mature vascular endothelial cells in vivo and ex vivo, which may contribute to cardiovascular complications in SARS-CoV-2 infection, including multipleorgan failure.},
  language  = {en}
}
@article{WagnerMottUpcinetal.2021,
  author    = {Wagner, Nicole and Mott, Kristina and Upcin, Berin and Stegner, David and Schulze, Harald and Erg{\"u}n, S{\"u}leyman},
  title     = {CXCL12-abundant reticular (CAR) cells direct megakaryocyte protrusions across the bone marrow sinusoid wall},
  series = {Cells},
  volume    = {10},
  journal   = {Cells},
  number    = {4},
  issn      = {2073-4409},
  doi       = {10.3390/cells10040722},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234180},
  year      = {2021},
  abstract  = {Megakaryocytes (MKs) release platelets into the lumen of bone marrow (BM) sinusoids while remaining to reside within the BM. The morphogenetic events of this complex process are still not fully understood. We combined confocal laser scanning microscopy with transmission and serial block-face scanning electron microscopy followed by 3D-reconstruction on mouse BM tissue sections. These analyses revealed that MKs in close vicinity to BM sinusoid (BMS) wall first induce the lateral retraction of CXCL12-abundant reticular (CAR) cells (CAR), followed by basal lamina (BL) degradation enabling direct MK-sinusoidal endothelial cells (SECs) interaction. Subsequently, an endothelial engulfment starts that contains a large MK protrusion. Then, MK protrusions penetrate the SEC, transmigrate into the BMS lumen and form proplatelets that are in direct contact to the SEC surface. Furthermore, such processes are induced on several sites, as observed by 3D reconstructions. Our data demonstrate that MKs in interaction with CAR-cells actively induce BMS wall alterations, including CAR-cell retraction, BL degradation, and SEC engulfment containing a large MK protrusion. This results in SEC penetration enabling the migration of MK protrusion into the BMS lumen where proplatelets that are adherent to the luminal SEC surface are formed and contribute to platelet release into the blood circulation.},
  language  = {en}
}
@article{KoenigerBellMifkaetal.2021,
  author    = {Koeniger, Tobias and Bell, Luisa and Mifka, Anika and Enders, Michael and Hautmann, Valentin and Mekala, Subba Rao and Kirchner, Philipp and Ekici, Arif B. and Schulz, Christian and W{\"o}rsd{\"o}rfer, Philipp and Mencl, Stine and Kleinschnitz, Christoph and Erg{\"u}n, S{\"u}leyman and Kuerten, Stefanie},
  title     = {Bone marrow-derived myeloid progenitors in the leptomeninges of adult mice},
  series = {Stem Cells},
  volume    = {39},
  journal   = {Stem Cells},
  number    = {2},
  doi       = {10.1002/stem.3311},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-224452},
  pages     = {227 -- 239},
  year      = {2021},
  abstract  = {Although the bone marrow contains most hematopoietic activity during adulthood, hematopoietic stem and progenitor cells can be recovered from various extramedullary sites. Cells with hematopoietic progenitor properties have even been reported in the adult brain under steady-state conditions, but their nature and localization remain insufficiently defined. Here, we describe a heterogeneous population of myeloid progenitors in the leptomeninges of adult C57BL/6 mice. This cell pool included common myeloid, granulocyte/macrophage, and megakaryocyte/erythrocyte progenitors. Accordingly, it gave rise to all major myelo-erythroid lineages in clonogenic culture assays. Brain-associated progenitors persisted after tissue perfusion and were partially inaccessible to intravenous antibodies, suggesting their localization behind continuous blood vessel endothelium such as the blood-arachnoid barrier. Flt3\(^{Cre}\) lineage tracing and bone marrow transplantation showed that the precursors were derived from adult hematopoietic stem cells and were most likely continuously replaced via cell trafficking. Importantly, their occurrence was tied to the immunologic state of the central nervous system (CNS) and was diminished in the context of neuroinflammation and ischemic stroke. Our findings confirm the presence of myeloid progenitors at the meningeal border of the brain and lay the foundation to unravel their possible functions in CNS surveillance and local immune cell production.},
  language  = {en}
}
@article{BeheraJainGangulietal.2022,
  author    = {Behera, Ananyaashree and Jain, Preeti and Ganguli, Geetanjali and Biswas, Mainak and Padhi, Avinash and Pattanaik, Kali Prasad and Nayak, Barsa and Erg{\"u}n, S{\"u}leyman and Hagens, Kristine and Redinger, Natalja and Saqib, Mohd and Mishra, Bibhuti B. and Schaible, Ulrich E. and Karnati, Srikanth and Sonawane, Avinash},
  title     = {Mycobacterium tuberculosis acetyltransferase suppresses oxidative stress by inducing peroxisome formation in macrophages},
  series = {International Journal of Molecular Sciences},
  volume    = {23},
  journal   = {International Journal of Molecular Sciences},
  number    = {5},
  issn      = {1422-0067},
  doi       = {10.3390/ijms23052584},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284080},
  year      = {2022},
  abstract  = {Mycobacterium tuberculosis (Mtb) inhibits host oxidative stress responses facilitating its survival in macrophages; however, the underlying molecular mechanisms are poorly understood. Here, we identified a Mtb acetyltransferase (Rv3034c) as a novel counter actor of macrophage oxidative stress responses by inducing peroxisome formation. An inducible Rv3034c deletion mutant of Mtb failed to induce peroxisome biogenesis, expression of the peroxisomal β-oxidation pathway intermediates (ACOX1, ACAA1, MFP2) in macrophages, resulting in reduced intracellular survival compared to the parental strain. This reduced virulence phenotype was rescued by repletion of Rv3034c. Peroxisome induction depended on the interaction between Rv3034c and the macrophage mannose receptor (MR). Interaction between Rv3034c and MR induced expression of the peroxisomal biogenesis proteins PEX5p, PEX13p, PEX14p, PEX11β, PEX19p, the peroxisomal membrane lipid transporter ABCD3, and catalase. Expression of PEX14p and ABCD3 was also enhanced in lungs from Mtb aerosol-infected mice. This is the first report that peroxisome-mediated control of ROS balance is essential for innate immune responses to Mtb but can be counteracted by the mycobacterial acetyltransferase Rv3034c. Thus, peroxisomes represent interesting targets for host-directed therapeutics to tuberculosis.},
  language  = {en}
}
@article{CapetianMuellerVolkmannetal.2020,
  author    = {Capetian, Philipp and M{\"u}ller, Lorenz and Volkmann, Jens and Heckmann, Manfred and Erg{\"u}n, S{\"u}leyman and Wagner, Nicole},
  title     = {Visualizing the synaptic and cellular ultrastructure in neurons differentiated from human induced neural stem cells - an optimized protocol},
  series = {International Journal of Molecular Sciences},
  volume    = {21},
  journal   = {International Journal of Molecular Sciences},
  number    = {5},
  issn      = {1422-0067},
  doi       = {10.3390/ijms21051708},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236053},
  year      = {2020},
  abstract  = {The size of the synaptic subcomponents falls below the limits of visible light microscopy. Despite new developments in advanced microscopy techniques, the resolution of transmission electron microscopy (TEM) remains unsurpassed. The requirements of tissue preservation are very high, and human post mortem material often does not offer adequate quality. However, new reprogramming techniques that generate human neurons in vitro provide samples that can easily fulfill these requirements. The objective of this study was to identify the culture technique with the best ultrastructural preservation in combination with the best embedding and contrasting technique for visualizing neuronal elements. Two induced neural stem cell lines derived from healthy control subjects underwent differentiation either adherent on glass coverslips, embedded in a droplet of highly concentrated Matrigel, or as a compact neurosphere. Afterward, they were fixed using a combination of glutaraldehyde (GA) and paraformaldehyde (PFA) followed by three approaches (standard stain, Ruthenium red stain, high contrast en-bloc stain) using different combinations of membrane enhancing and contrasting steps before ultrathin sectioning and imaging by TEM. The compact free-floating neurospheres exhibited the best ultrastructural preservation. High-contrast en-bloc stain offered particularly sharp staining of membrane structures and the highest quality visualization of neuronal structures. In conclusion, compact neurospheres growing under free-floating conditions in combination with a high contrast en-bloc staining protocol, offer the optimal preservation and contrast with a particular focus on visualizing membrane structures as required for analyzing synaptic structures.},
  language  = {en}
}
@article{MeyerWatermannDreyeretal.2021,
  author    = {Meyer, Malin Tordis and Watermann, Christoph and Dreyer, Thomas and Erg{\"u}n, S{\"u}leyman and Karnati, Srikanth},
  title     = {2021 update on diagnostic markers and translocation in salivary gland tumors},
  series = {International Journal of Molecular Sciences},
  volume    = {22},
  journal   = {International Journal of Molecular Sciences},
  number    = {13},
  issn      = {1422-0067},
  doi       = {10.3390/ijms22136771},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261057},
  year      = {2021},
  abstract  = {Salivary gland tumors are a rare tumor entity within malignant tumors of all tissues. The most common are malignant mucoepidermoid carcinoma, adenoid cystic carcinoma, and acinic cell carcinoma. Pleomorphic adenoma is the most recurrent form of benign salivary gland tumor. Due to their low incidence rates and complex histological patterns, they are difficult to diagnose accurately. Malignant tumors of the salivary glands are challenging in terms of differentiation because of their variability in histochemistry and translocations. Therefore, the primary goal of the study was to review the current literature to identify the recent developments in histochemical diagnostics and translocations for differentiating salivary gland tumors.},
  language  = {en}
}
@article{KarnatiGuntasRajendranetal.2022,
  author    = {Karnati, Srikanth and Guntas, Gulcan and Rajendran, Ranjithkumar and Shityakov, Sergey and H{\"o}ring, Marcus and Liebisch, Gerhard and Kosanovic, Djuro and Erg{\"u}n, S{\"u}leyman and Nagai, Michiaki and F{\"o}rster, Carola Y.},
  title     = {Quantitative lipidomic analysis of Takotsubo syndrome patients' serum},
  series = {Frontiers in Cardiovascular Medicine},
  volume    = {9},
  journal   = {Frontiers in Cardiovascular Medicine},
  number    = {797154},
  issn      = {2297-055X},
  doi       = {10.3389/fcvm.2022.797154},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-270832},
  year      = {2022},
  abstract  = {Takotsubo syndrome (TTS), also known as the transient left ventricular apical ballooning syndrome, is in contemporary times known as novel acute cardiac syndrome. It is characterized by transient left ventricular apical akinesis and hyperkinesis of the basal left ventricular portions. Although the precise etiology of TTS is unknown, events like the sudden release of stress hormones, such as the catecholamines and the increased inflammatory status might be plausible causes leading to the cardiovascular pathologies. Recent studies have highlighted that an imbalance in lipid accumulation might promote a deviant immune response as observed in TTS. However, there is no information on comprehensive profiling of serum lipids of TTS patients. Therefore, we investigated a detailed quantitative lipid analysis of TTS patients using ES-MSI. Our results showed significant differences in the majority of lipid species composition in the TTS patients compared to the control group. Furthermore, the computational analyses presented was able to link the altered lipids to the pro-inflammatory cytokines and disseminate possible mechanistic pathways involving TNFα and IL-6. Taken together, our study provides an extensive quantitative lipidome of TTS patients, which may provide a valuable Pre-diagnostic tool. This would facilitate the elucidation of the underlying mechanisms of the disease and to prevent the development of TTS in the future.},
  language  = {en}
}
@article{WoersdoerferDaldaKernetal.2019,
  author    = {W{\"o}rsd{\"o}rfer, Philipp and Dalda, Nahide and Kern, Anna and Kr{\"u}ger, Sarah and Wagner, Nicole and Kwok, Chee Keong and Henke, Erik and Erg{\"u}n, S{\"u}leyman},
  title     = {Generation of complex human organoid models including vascular networks by incorporation of mesodermal progenitor cells},
  series = {Scientific Reports},
  volume    = {9},
  journal   = {Scientific Reports},
  doi       = {10.1038/s41598-019-52204-7},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-202681},
  pages     = {15663},
  year      = {2019},
  abstract  = {Organoids derived from human pluripotent stem cells are interesting models to study mechanisms of morphogenesis and promising platforms for disease modeling and drug screening. However, they mostly remain incomplete as they lack stroma, tissue resident immune cells and in particular vasculature, which create important niches during development and disease. We propose, that the directed incorporation of mesodermal progenitor cells (MPCs) into organoids will overcome the aforementioned limitations. In order to demonstrate the feasibility of the method, we generated complex human tumor as well as neural organoids. We show that the formed blood vessels display a hierarchic organization and mural cells are assembled into the vessel wall. Moreover, we demonstrate a typical blood vessel ultrastructure including endothelial cell-cell junctions, a basement membrane as well as luminal caveolae and microvesicles. We observe a high plasticity in the endothelial network, which expands, while the organoids grow and is responsive to anti-angiogenic compounds and pro-angiogenic conditions such as hypoxia. We show that vessels within tumor organoids connect to host vessels following transplantation. Remarkably, MPCs also deliver Iba1\(^+\) cells that infiltrate the neural tissue in a microglia-like manner.},
  language  = {en}
}
@article{JanzZinkCirnuetal.2021,
  author    = {Janz, Anna and Zink, Miriam and Cirnu, Alexandra and Hartleb, Annika and Albrecht, Christina and Rost, Simone and Klopocki, Eva and G{\"u}nther, Katharina and Edenhofer, Frank and Erg{\"u}n, S{\"u}leyman and Gerull, Brenda},
  title     = {CRISPR/Cas9-edited PKP2 knock-out (JMUi001-A-2) and DSG2 knock-out (JMUi001-A-3) iPSC lines as an isogenic human model system for arrhythmogenic cardiomyopathy (ACM)},
  series = {Stem Cell Research},
  volume    = {53},
  journal   = {Stem Cell Research},
  doi       = {10.1016/j.scr.2021.102256},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259846},
  pages     = {102256},
  year      = {2021},
  abstract  = {Arrhythmogenic cardiomyopathy (ACM) is characterized by fibro-fatty replacement of the myocardium, heart failure and life-threatening ventricular arrhythmias. Causal mutations were identified in genes encoding for proteins of the desmosomes, predominantly plakophilin-2 (PKP2) and desmoglein-2 (DSG2). We generated gene-edited knock-out iPSC lines for PKP2 (JMUi001-A-2) and DSG2 (JMUi001-A-3) using the CRISPR/Cas9 system in a healthy control iPSC background (JMUi001A). Stem cell-like morphology, robust expression of pluripotency markers, embryoid body formation and normal karyotypes confirmed the generation of high quality iPSCs to provide a novel isogenic human in vitro model system mimicking ACM when differentiated into cardiomyocytes.},
  language  = {en}
}
@article{UpcinHenkeKleefeldtetal.2021,
  author    = {Upcin, Berin and Henke, Erik and Kleefeldt, Florian and Hoffmann, Helene and Rosenwald, Andreas and Irmak-Sav, Ster and Aktas, Huseyin Bertal and R{\"u}ckschloß, Uwe and Erg{\"u}n, S{\"u}leyman},
  title     = {Contribution of adventitia-derived stem and progenitor cells to new vessel formation in tumors},
  series = {Cells},
  volume    = {10},
  journal   = {Cells},
  number    = {7},
  doi       = {10.3390/cells10071719},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-242577},
  year      = {2021},
  abstract  = {Blocking tumor vascularization has not yet come to fruition to the extent it was hoped for, as angiogenesis inhibitors have shown only partial success in the clinic. We hypothesized that under- appreciated vascular wall-resident stem and progenitor cells (VW-SPCs) might be involved in tumor vascularization and influence effectiveness of anti-angiogenic therapy. Indeed, in patient samples, we observed that vascular adventitia-resident CD34\(^+\) VW-SPCs are recruited to tumors in situ from co-opted vessels. To elucidate this in detail, we established an ex vivo model using concomitant embedding of multi-cellular tumor spheroids (MCTS) and mouse aortic rings (ARs) into collagen gels, similar to the so-called aortic ring assay (ARA). Moreover, ARA was modified by removing the ARs' adventitia that harbors VW-SPCs. Thus, this model enabled distinguishing the contribution of VW-SPCs from that of mature endothelial cells (ECs) to new vessel formation. Our results show that the formation of capillary-like sprouts is considerably delayed, and their number and network formation were significantly reduced by removing the adventitia. Substituting iPSC-derived neural spheroids for MCTS resulted in distinct sprouting patterns that were also strongly influenced by the presence or absence of VW-SPCs, also underlying the involvement of these cells in non-pathological vascularization. Our data suggest that more comprehensive approaches are needed in order to block all of the mechanisms contributing to tumor vascularization.},
  language  = {en}
}
@article{KustiatiErguenKarnatietal.2022,
  author    = {Kustiati, Ulayatul and Erg{\"u}n, Suleyman and Karnati, Srikanth and Nugrahaningsih, Dwi Aris Agung and Kusindarta, Dwi Liliek and Wihadmadyatami, Hevi},
  title     = {Ethanolic extract of Ocimum sanctum Linn. Inhibits cell migration of human lung adenocarcinoma cells (A549) by downregulation of integrin αvβ3, α5β1, and VEGF},
  series = {Scientia Pharmaceutica},
  volume    = {90},
  journal   = {Scientia Pharmaceutica},
  number    = {4},
  issn      = {2218-0532},
  doi       = {10.3390/scipharm90040069},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-290540},
  year      = {2022},
  abstract  = {Adenocarcinoma lung cancer is a type of non-small cell lung carcinoma (NSCLC), which accounts for 85\% of lung cancer incidence globally. The therapies that are being applied, both conventional therapies and antibody-based treatments, are still found to have side effects. Several previous studies have demonstrated the ability of the ethanolic extract of Ocimum sanctum Linn. (EEOS) as an ethnomedicine with anti-tumor properties. The aim of this study was to determine the effect of Ocimum sanctum Linn. ethanolic extract in inhibiting the proliferation, angiogenesis, and migration of A549 cells (NSCLC). The adhesion as well as the migration assay was performed. Furthermore, enzyme-linked immunosorbent assay (ELISA) was used to measure the expression of αvβ3 integrins, α5β1 integrins, and VEGF. The cells were divided into the following treatment groups: control (non-treated/NT), positive control (AP3/inhibitor β3 80 µg/mL), cisplatin (9 µg/mL), and EEOS at concentrations of 50, 70, 100, and 200 µg/mL. The results showed that EEOS inhibits the adhesion ability and migration of A549 cells, with an optimal concentration of 200 µg/mL. ELISA testing showed that the group of A549 cells given EEOS 200 µg/mL presented a decrease in the optimal expression of integrin α5β1, integrin αvβ3, and VEGF.},
  language  = {en}
}
@article{ShityakovNagaiErguenetal.2022,
  author    = {Shityakov, Sergey and Nagai, Michiaki and Erg{\"u}n, S{\"u}leyman and Braunger, Barbara M. and F{\"o}rster, Carola Y.},
  title     = {The protective effects of neurotrophins and microRNA in diabetic retinopathy, nephropathy and heart failure via regulating endothelial function},
  series = {Biomolecules},
  volume    = {12},
  journal   = {Biomolecules},
  number    = {8},
  issn      = {2218-273X},
  doi       = {10.3390/biom12081113},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-285966},
  year      = {2022},
  abstract  = {Diabetes mellitus is a common disease affecting more than 537 million adults worldwide. The microvascular complications that occur during the course of the disease are widespread and affect a variety of organ systems in the body. Diabetic retinopathy is one of the most common long-term complications, which include, amongst others, endothelial dysfunction, and thus, alterations in the blood-retinal barrier (BRB). This particularly restrictive physiological barrier is important for maintaining the neuroretina as a privileged site in the body by controlling the inflow and outflow of fluid, nutrients, metabolic end products, ions, and proteins. In addition, people with diabetic retinopathy (DR) have been shown to be at increased risk for systemic vascular complications, including subclinical and clinical stroke, coronary heart disease, heart failure, and nephropathy. DR is, therefore, considered an independent predictor of heart failure. In the present review, the effects of diabetes on the retina, heart, and kidneys are described. In addition, a putative common microRNA signature in diabetic retinopathy, nephropathy, and heart failure is discussed, which may be used in the future as a biomarker to better monitor disease progression. Finally, the use of miRNA, targeted neurotrophin delivery, and nanoparticles as novel therapeutic strategies is highlighted.},
  language  = {en}
}
@article{BielmeierRothSchmittetal.2021,
  author    = {Bielmeier, Christina B. and Roth, Saskia and Schmitt, Sabrina I. and Boneva, Stefaniya K. and Schlecht, Anja and Vallon, Mario and Tamm, Ernst R. and Erg{\"u}n, S{\"u}leyman and Neueder, Andreas and Braunger, Barbara M.},
  title     = {Transcriptional profiling identifies upregulation of neuroprotective pathways in retinitis pigmentosa},
  series = {International Journal of Molecular Sciences},
  volume    = {22},
  journal   = {International Journal of Molecular Sciences},
  number    = {12},
  issn      = {1422-0067},
  doi       = {10.3390/ijms22126307},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260769},
  year      = {2021},
  abstract  = {Hereditary retinal degenerations like retinitis pigmentosa (RP) are among the leading causes of blindness in younger patients. To enable in vivo investigation of cellular and molecular mechanisms responsible for photoreceptor cell death and to allow testing of therapeutic strategies that could prevent retinal degeneration, animal models have been created. In this study, we deeply characterized the transcriptional profile of mice carrying the transgene rhodopsin V20G/P23H/P27L (VPP), which is a model for autosomal dominant RP. We examined the degree of photoreceptor degeneration and studied the impact of the VPP transgene-induced retinal degeneration on the transcriptome level of the retina using next generation RNA sequencing (RNASeq) analyses followed by weighted correlation network analysis (WGCNA). We furthermore identified cellular subpopulations responsible for some of the observed dysregulations using in situ hybridizations, immunofluorescence staining, and 3D reconstruction. Using RNASeq analysis, we identified 9256 dysregulated genes and six significantly associated gene modules in the subsequently performed WGCNA. Gene ontology enrichment showed, among others, dysregulation of genes involved in TGF-β regulated extracellular matrix organization, the (ocular) immune system/response, and cellular homeostasis. Moreover, heatmaps confirmed clustering of significantly dysregulated genes coding for components of the TGF-β, G-protein activated, and VEGF signaling pathway. 3D reconstructions of immunostained/in situ hybridized sections revealed retinal neurons and M{\"u}ller cells as the major cellular population expressing representative components of these signaling pathways. The predominant effect of VPP-induced photoreceptor degeneration pointed towards induction of neuroinflammation and the upregulation of neuroprotective pathways like TGF-β, G-protein activated, and VEGF signaling. Thus, modulation of these processes and signaling pathways might represent new therapeutic options to delay the degeneration of photoreceptors in diseases like RP.},
  language  = {en}
}
@article{SchmidtAltDeoghareetal.2022,
  author    = {Schmidt, Sven and Alt, Yvonne and Deoghare, Nikita and Kr{\"u}ger, Sarah and Kern, Anna and Rockel, Anna Frederike and Wagner, Nicole and Erg{\"u}n, S{\"u}leyman and W{\"o}rsd{\"o}rfer, Philipp},
  title     = {A blood vessel organoid model recapitulating aspects of vasculogenesis, angiogenesis and vessel wall maturation},
  series = {Organoids},
  volume    = {1},
  journal   = {Organoids},
  number    = {1},
  issn      = {2674-1172},
  doi       = {10.3390/organoids1010005},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284043},
  pages     = {41 -- 53},
  year      = {2022},
  abstract  = {Blood vessel organoids are an important in vitro model to understand the underlying mechanisms of human blood vessel development and for toxicity testing or high throughput drug screening. Here we present a novel, cost-effective, and easy to manufacture vascular organoid model. To engineer the organoids, a defined number of human induced pluripotent stem cells are seeded in non-adhesive agarose coated wells of a 96-well plate and directed towards a lateral plate mesoderm fate by activation of Wnt and BMP4 signaling. We observe the formation of a circular layer of angioblasts around days 5-6. Induced by VEGF application, CD31\(^+\) vascular endothelial cells appear within this vasculogenic zone at approximately day 7 of organoid culture. These cells arrange to form a primitive vascular plexus from which angiogenic sprouting is observed after 10 days of culture. The differentiation outcome is highly reproducible, and the size of organoids is scalable depending on the number of starting cells. We observe that the initial vascular ring forms at the interface between two cell populations. The inner cellular compartment can be distinguished from the outer by the expression of GATA6, a marker of lateral plate mesoderm. Finally, 14-days-old organoids were transplanted on the chorioallantois membrane of chicken embryos resulting in a functional connection of the human vascular network to the chicken circulation. Perfusion of the vessels leads to vessel wall maturation and remodeling as indicated by the formation of a continuous layer of smooth muscle actin expressing cells enwrapping the endothelium. In summary, our organoid model recapitulates human vasculogenesis, angiogenesis as well as vessel wall maturation and therefore represents an easy and cost-effective tool to study all steps of blood vessel development and maturation directly in the human setting without animal experimentation.},
  language  = {en}
}
@article{ErguenWoersdoerfer2022,
  author    = {Erg{\"u}n, S{\"u}leyman and W{\"o}rsd{\"o}rfer, Philipp},
  title     = {Organoids, assembloids and embryoids: New avenues for developmental biology, disease modeling, drug testing and toxicity assessment without animal experimentation},
  series = {Organoids},
  volume    = {1},
  journal   = {Organoids},
  number    = {1},
  issn      = {2674-1172},
  doi       = {10.3390/organoids1010004},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284101},
  pages     = {37 -- 40},
  year      = {2022},
  abstract  = {No abstract available},
  language  = {en}
}
@article{IUedaWoersdoerferetal.2020,
  author    = {I, Takashi and Ueda, Yuichiro and W{\"o}rsd{\"o}rfer, Philipp and Sumita, Yoshinori and Asahina, Izumi and Erg{\"u}n, S{\"u}leyman},
  title     = {Resident CD34-positive cells contribute to peri-endothelial cells and vascular morphogenesis in salivary gland after irradiation},
  series = {Journal of Neural Transmission},
  volume    = {127},
  journal   = {Journal of Neural Transmission},
  issn      = {0300-9564},
  doi       = {10.1007/s00702-020-02256-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235613},
  pages     = {1467-1479},
  year      = {2020},
  abstract  = {Salivary gland (SG) hypofunction is a common post-radiotherapy complication. Besides the parenchymal damage after irradiation (IR), there are also effects on mesenchymal stem cells (MSCs) which were shown to contribute to regeneration and repair of damaged tissues by differentiating into stromal cell types or releasing vesicles and soluble factors supporting the healing processes. However, there are no adequate reports about their roles during SG damage and regeneration so far. Using an irradiated SG mouse model, we performed certain immunostainings on tissue sections of submandibular glands at different time points after IR. Immunostaining for CD31 revealed that already one day after IR, vascular impairment was induced at the level of capillaries. In addition, the expression of CD44—a marker of acinar cells—diminished gradually after IR and, by 20 weeks, almost disappeared. In contrast, the number of CD34-positive cells significantly increased 4 weeks after IR and some of the CD34-positive cells were found to reside within the adventitia of arteries and veins. Laser confocal microscopic analyses revealed an accumulation of CD34-positive cells within the area of damaged capillaries where they were in close contact to the CD31-positive endothelial cells. At 4 weeks after IR, a fraction of the CD34-positive cells underwent differentiation into α-SMA-positive cells, which suggests that they may contribute to regeneration of smooth muscle cells and/or pericytes covering the small vessels from the outside. In conclusion, SG-resident CD34-positive cells represent a population of progenitors that could contribute to new vessel formation and/or remodeling of the pre-existing vessels after IR and thus, might be an important player during SG tissue healing.},
  language  = {en}
}
@article{WoersdoerferIAsahinaetal.2020,
  author    = {W{\"o}rsd{\"o}rfer, Philipp and I, Takashi and Asahina, Izumi and Sumita, Yoshinori and Erg{\"u}n, S{\"u}leyman},
  title     = {Do not keep it simple: recent advances in the generation of complex organoids},
  series = {Journal of Neural Transmission},
  volume    = {127},
  journal   = {Journal of Neural Transmission},
  issn      = {0300-9564},
  doi       = {10.1007/s00702-020-02198-8},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235628},
  pages     = {1569-1577},
  year      = {2020},
  abstract  = {3D cell culture models which closely resemble real human tissues are of high interest for disease modelling, drug screening as well as a deeper understanding of human developmental biology. Such structures are termed organoids. Within the last years, several human organoid models were described. These are usually stem cell derived, arise by self-organization, mimic mechanisms of normal tissue development, show typical organ morphogenesis and recapitulate at least some organ specific functions. Many tissues have been reproduced in vitro such as gut, liver, lung, kidney and brain. The resulting entities can be either derived from an adult stem cell population, or generated from pluripotent stem cells using a specific differentiation protocol. However, many organoid models only recapitulate the organs parenchyma but are devoid of stromal components such as blood vessels, connective tissue and inflammatory cells. Recent studies show that the incorporation of endothelial and mesenchymal cells into organoids improved their maturation and might be required to create fully functional micro-tissues, which will allow deeper insights into human embryogenesis as well as disease development and progression. In this review article, we will summarize and discuss recent works trying to incorporate stromal components into organoids, with a special focus on neural organoid models.},
  language  = {en}
}
@article{HuflageGrunzPatzeretal.2023,
  author    = {Huflage, Henner and Grunz, Jan-Peter and Patzer, Theresa Sophie and Pannenbecker, Pauline and Feldle, Philipp and Sauer, Stephanie Tina and Petritsch, Bernhard and Erg{\"u}n, S{\"u}leyman and Bley, Thorsten Alexander and Kunz, Andreas Steven},
  title     = {Potential of unenhanced ultra-low-dose abdominal photon-counting CT with tin filtration: a cadaveric study},
  series = {Diagnostics},
  volume    = {13},
  journal   = {Diagnostics},
  number    = {4},
  issn      = {2075-4418},
  doi       = {10.3390/diagnostics13040603},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304122},
  year      = {2023},
  abstract  = {Objectives: This study investigated the feasibility and image quality of ultra-low-dose unenhanced abdominal CT using photon-counting detector technology and tin prefiltration. Materials and Methods: Employing a first-generation photon-counting CT scanner, eight cadaveric specimens were examined both with tin prefiltration (Sn 100 kVp) and polychromatic (120 kVp) scan protocols matched for radiation dose at three different levels: standard-dose (3 mGy), low-dose (1 mGy) and ultra-low-dose (0.5 mGy). Image quality was evaluated quantitatively by means of contrast-to-noise-ratios (CNR) with regions of interest placed in the renal cortex and subcutaneous fat. Additionally, three independent radiologists performed subjective evaluation of image quality. The intraclass correlation coefficient was calculated as a measure of interrater reliability. Results: Irrespective of scan mode, CNR in the renal cortex decreased with lower radiation dose. Despite similar mean energy of the applied x-ray spectrum, CNR was superior for Sn 100 kVp over 120 kVp at standard-dose (17.75 ± 3.51 vs. 14.13 ± 4.02), low-dose (13.99 ± 2.6 vs. 10.68 ± 2.17) and ultra-low-dose levels (8.88 ± 2.01 vs. 11.06 ± 1.74) (all p ≤ 0.05). Subjective image quality was highest for both standard-dose protocols (score 5; interquartile range 5-5). While no difference was ascertained between Sn 100 kVp and 120 kVp examinations at standard and low-dose levels, the subjective image quality of tin-filtered scans was superior to 120 kVp with ultra-low radiation dose (p < 0.05). An intraclass correlation coefficient of 0.844 (95\% confidence interval 0.763-0.906; p < 0.001) indicated good interrater reliability. Conclusions: Photon-counting detector CT permits excellent image quality in unenhanced abdominal CT with very low radiation dose. Employment of tin prefiltration at 100 kVp instead of polychromatic imaging at 120 kVp increases the image quality even further in the ultra-low-dose range of 0.5 mGy.},
  language  = {en}
}
@article{PatzerKunzHuflageetal.2023,
  author    = {Patzer, Theresa Sophie and Kunz, Andreas Steven and Huflage, Henner and Conrads, Nora and Luetkens, Karsten Sebastian and Pannenbecker, Pauline and Paul, Mila Marie and Erg{\"u}n, S{\"u}leyman and Bley, Thorsten Alexander and Grunz, Jan-Peter},
  title     = {Ultrahigh-resolution photon-counting CT in cadaveric fracture models: spatial frequency is not everything},
  series = {Diagnostics},
  volume    = {13},
  journal   = {Diagnostics},
  number    = {10},
  issn      = {2075-4418},
  doi       = {10.3390/diagnostics13101677},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-319281},
  year      = {2023},
  abstract  = {In this study, the impact of reconstruction sharpness on the visualization of the appendicular skeleton in ultrahigh-resolution (UHR) photon-counting detector (PCD) CT was investigated. Sixteen cadaveric extremities (eight fractured) were examined with a standardized 120 kVp scan protocol (CTDI\(_{vol}\) 10 mGy). Images were reconstructed with the sharpest non-UHR kernel (Br76) and all available UHR kernels (Br80 to Br96). Seven radiologists evaluated image quality and fracture assessability. Interrater agreement was assessed with the intraclass correlation coefficient. For quantitative comparisons, signal-to-noise-ratios (SNRs) were calculated. Subjective image quality was best for Br84 (median 1, interquartile range 1-3; p ≤ 0.003). Regarding fracture assessability, no significant difference was ascertained between Br76, Br80 and Br84 (p > 0.999), with inferior ratings for all sharper kernels (p < 0.001). Interrater agreement for image quality (0.795, 0.732-0.848; p < 0.001) and fracture assessability (0.880; 0.842-0.911; p < 0.001) was good. SNR was highest for Br76 (3.4, 3.0-3.9) with no significant difference to Br80 and Br84 (p > 0.999). Br76 and Br80 produced higher SNRs than all kernels sharper than Br84 (p ≤ 0.026). In conclusion, PCD-CT reconstructions with a moderate UHR kernel offer superior image quality for visualizing the appendicular skeleton. Fracture assessability benefits from sharp non-UHR and moderate UHR kernels, while ultra-sharp reconstructions incur augmented image noise.},
  language  = {en}
}
@article{WoersdoerferErguen2023,
  author    = {W{\"o}rsd{\"o}rfer, Philipp and Erg{\"u}n, S{\"u}leyman},
  title     = {"Organoids": insights from the first issues},
  series = {Organoids},
  volume    = {2},
  journal   = {Organoids},
  number    = {2},
  issn      = {2674-1172},
  doi       = {10.3390/organoids2020006},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313694},
  pages     = {79 -- 81},
  year      = {2023},
  abstract  = {No abstract available},
  language  = {en}
}
@article{AktasUpcinHenkeetal.2019,
  author    = {Aktas, Bertal H. and Upcin, Berin and Henke, Erik and Padmasekar, Manju and Qin, Xuebin and Erg{\"u}n, S{\"u}leyman},
  title     = {The Best for the Most Important: Maintaining a Pristine Proteome in Stem and Progenitor Cells},
  series = {Stem Cells International},
  journal   = {Stem Cells International},
  doi       = {10.1155/2019/1608787},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-227769},
  pages     = {1-20},
  year      = {2019},
  abstract  = {Pluripotent stem cells give rise to reproductively enabled offsprings by generating progressively lineage-restricted multipotent stem cells that would differentiate into lineage-committed stem and progenitor cells. These lineage-committed stem and progenitor cells give rise to all adult tissues and organs. Adult stem and progenitor cells are generated as part of the developmental program and play critical roles in tissue and organ maintenance and/or regeneration. The ability of pluripotent stem cells to self-renew, maintain pluripotency, and differentiate into a multicellular organism is highly dependent on sensing and integrating extracellular and extraorganismal cues. Proteins perform and integrate almost all cellular functions including signal transduction, regulation of gene expression, metabolism, and cell division and death. Therefore, maintenance of an appropriate mix of correctly folded proteins, a pristine proteome, is essential for proper stem cell function. The stem cells' proteome must be pristine because unfolded, misfolded, or otherwise damaged proteins would interfere with unlimited self-renewal, maintenance of pluripotency, differentiation into downstream lineages, and consequently with the development of properly functioning tissue and organs. Understanding how various stem cells generate and maintain a pristine proteome is therefore essential for exploiting their potential in regenerative medicine and possibly for the discovery of novel approaches for maintaining, propagating, and differentiating pluripotent, multipotent, and adult stem cells as well as induced pluripotent stem cells. In this review, we will summarize cellular networks used by various stem cells for generation and maintenance of a pristine proteome. We will also explore the coordination of these networks with one another and their integration with the gene regulatory and signaling networks.},
  language  = {en}
}