@article{vonBuerenOehlerShalabyetal.2011,
  author    = {von Bueren, Andr{\´e} O. and Oehler, Christoph and Shalaby, Tarek and von Hoff, Katja and Pruschy, Martin and Seifert, Burkhardt and Gerber, Nicolas U. and Warmuth-Metz, Monika and Stearns, Duncan and Eberhart, Charles G. and Kortmann, Rolf D. and Rutkowski, Stefan and Grotzer, Michael A.},
  title     = {c-MYC expression sensitizes medulloblastoma cells to radio- and chemotherapy and has no impact on response in medulloblastoma patients},
  series = {BMC Cancer},
  volume    = {11},
  journal   = {BMC Cancer},
  number    = {74},
  doi       = {10.1186/1471-2407-11-74},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134185},
  pages     = {1-11},
  year      = {2011},
  abstract  = {Background: To study whether and how c-MYC expression determines response to radio-and chemotherapy in childhood medulloblastoma (MB). Methods: We used DAOY and UW228 human MB cells engineered to stably express different levels of c-MYC, and tested whether c-MYC expression has an effect on radio-and chemosensitivity using the colorimetric 3-(4,5-dimethylthiazol- 2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay, clonogenic survival, apoptosis assays, cell cycle analysis, and western blot assessment. In an effort to validate our results, we analyzed c-MYC mRNA expression in formalin-fixed paraffin-embedded tumor samples from well-documented patients with postoperative residual tumor and compared c-MYC mRNA expression with response to radio-and chemotherapy as examined by neuroradiological imaging. Results: In DAOY -and to a lesser extent in UW228 -cells expressing high levels of c-MYC, the cytotoxicity of cisplatin, and etoposide was significantly higher when compared with DAOY/UW228 cells expressing low levels of c-MYC. Irradiation-and chemotherapy-induced apoptotic cell death was enhanced in DAOY cells expressing high levels of c-MYC. The response of 62 of 66 residual tumors was evaluable and response to postoperative radio-(14 responders (CR, PR) vs. 5 non-responders (SD, PD)) or chemotherapy (23 CR/PR vs. 20 SD/PD) was assessed. c-MYC mRNA expression was similar in primary MB samples of responders and non-responders (Mann-Whitney U test, p = 0.50, ratio 0.49, 95\% CI 0.008-30.0 and p = 0.67, ratio 1.8, 95\% CI 0.14-23.5, respectively). Conclusions: c-MYC sensitizes MB cells to some anti-cancer treatments in vitro. As we failed to show evidence for such an effect on postoperative residual tumors when analyzed by imaging, additional investigations in xenografts and larger MB cohorts may help to define the exact function of c-MYC in modulating response to treatment.},
  language  = {en}
}
@article{NietzerBaurSieberetal.2016,
  author    = {Nietzer, Sarah and Baur, Florentin and Sieber, Stefan and Hansmann, Jan and Schwarz, Thomas and Stoffer, Carolin and H{\"a}fner, Heide and Gasser, Martin and Waaga-Gasser, Ana Maria and Walles, Heike and Dandekar, Gudrun},
  title     = {Mimicking metastases including tumor stroma: a new technique to generate a three-dimensional colorectal cancer model based on a biological decellularized intestinal scaffold},
  series = {Tissue Engineering Part C-Methods},
  volume    = {22},
  journal   = {Tissue Engineering Part C-Methods},
  number    = {7},
  doi       = {10.1089/ten.tec.2015.0557},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188202},
  pages     = {621-635},
  year      = {2016},
  abstract  = {Tumor models based on cancer cell lines cultured two-dimensionally (2D) on plastic lack histological complexity and functionality compared to the native microenvironment. Xenogenic mouse tumor models display higher complexity but often do not predict human drug responses accurately due to species-specific differences. We present here a three-dimensional (3D) in vitro colon cancer model based on a biological scaffold derived from decellularized porcine jejunum (small intestine submucosa+mucosa, SISmuc). Two different cell lines were used in monoculture or in coculture with primary fibroblasts. After 14 days of culture, we demonstrated a close contact of human Caco2 colon cancer cells with the preserved basement membrane on an ultrastructural level as well as morphological characteristics of a well-differentiated epithelium. To generate a tissue-engineered tumor model, we chose human SW480 colon cancer cells, a reportedly malignant cell line. Malignant characteristics were confirmed in 2D cell culture: SW480 cells showed higher vimentin and lower E-cadherin expression than Caco2 cells. In contrast to Caco2, SW480 cells displayed cancerous characteristics such as delocalized E-cadherin and nuclear location of beta-catenin in a subset of cells. One central drawback of 2D cultures-especially in consideration of drug testing-is their artificially high proliferation. In our 3D tissue-engineered tumor model, both cell lines showed decreased numbers of proliferating cells, thus correlating more precisely with observations of primary colon cancer in all stages (UICC I-IV). Moreover, vimentin decreased in SW480 colon cancer cells, indicating a mesenchymal to epithelial transition process, attributed to metastasis formation. Only SW480 cells cocultured with fibroblasts induced the formation of tumor-like aggregates surrounded by fibroblasts, whereas in Caco2 cocultures, a separate Caco2 cell layer was formed separated from the fibroblast compartment beneath. To foster tissue generation, a bioreactor was constructed for dynamic culture approaches. This induced a close tissue-like association of cultured tumor cells with fibroblasts reflecting tumor biopsies. Therapy with 5-fluorouracil (5-FU) was effective only in 3D coculture. In conclusion, our 3D tumor model reflects human tissue-related tumor characteristics, including lower tumor cell proliferation. It is now available for drug testing in metastatic context-especially for substances targeting tumor-stroma interactions.},
  language  = {en}
}
@phdthesis{Hochheimer2022,
  author    = {Hochheimer, Vanessa Christine},
  title     = {Of cells and enzymes: How dermal fibroblasts can impact pain in Fabry Disease and Why looking at the 3D-structure of α-Galactosidase A may be worthwhile for clinical management of Fabry patients},
  doi       = {10.25972/OPUS-29660},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-296607},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {Fabry Disease (FD) is a genetic lysosomal storage disorder based on mutations in the gene encoding α-Galactosidase A (α-GalA) leading to accumulation of globotriaosylceramide (Gb3). Missense mutations induce an amino acid exchange (AAE) in the α-GalA. Pain is a predominant symptom in FD and the pathophysiology is unclear. Skin punch biopsies were obtained from 40 adult FD patients and ten healthy controls and dermal fibroblast cultures were generated for cell culture experiments to investigate Gb3 load, gene and protein expression patterns and ion channel activity. The 3D-structure of α-GalA was downloaded into Pymol Graphics System and the AAE was depicted and located in order to investigate the correlation between the AAE location type in the α-GalA and the clinical FD phenotype. FD dermal fibroblasts showed high Gb3 load depending on treatment interval and expressed Kca1.1 channels. Activity was reduced in FD cells at baseline, but increased over-proportionately upon Gb3-cleavage by enzyme replacement therapy. Gene and protein expression of Kca1.1 was increased in FD cells. FD dermal fibroblasts showed higher gene expression of Notch1 and several cytokines. Further, it was shown that three different AAE location types can be differentiated: mutations in the active site ('active site'), those buried in the core of α-GalA ('buried') and those at another location, mostly on the protein surface ('other'). FD patients carrying active site or buried mutations showed a severe clinical phenotype with multi-organ manifestation and early disease onset. Patients with other mutations were less severely affected with oligo-organ manifestation sparing the nervous system and later disease onset. These results show that dermal fibroblasts may be involved in FD-associated pain and that stratification of FD patients carrying missense mutations by AAE location type may be an advantageous parameter that can help in the management of FD patients.},
  subject      = {Fabry-Krankheit},
  language  = {en}
}
@phdthesis{Schlesinger2024,
  author    = {Schlesinger, Tobias},
  title     = {Autolog zellbesiedelte Matrix zum Verschluss gastraler Inzisionen: Eine Machbarkeitsstudie im Schweinemodell},
  doi       = {10.25972/OPUS-30583},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-305832},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Einleitung: Strukturelle Defekte der gastrointestinalen Hohlorgane stellen ein allgegen-w{\"a}rtiges Problem im klinischen Alltag dar. Sie entstehen meist auf dem Boden einer ent-z{\"u}ndlichen oder tumor{\"o}sen Grunderkrankung und k{\"o}nnen außerdem traumatisch sowie durch medizinische Eingriffe hervorgerufen werden. In der Folge kommt es zur Kontami-nation des umliegenden Gewebes mit Magen- bzw. Darminhalt, wodurch delet{\"a}re Folgen wie eine systemische Infektion, also eine Sepsis mit Multiorganversagen drohen k{\"o}nnen. Vor diesem Hintergrund sind gastrointestinale Defekte immer als potenziell lebensbedroh-lich f{\"u}r den Patienten zu betrachten. Die ad{\"a}quate und kausale Behandlung erfolgt je nach {\"A}tiologie und Zustand des Patienten durch eine Operation oder eine endoskopische Inter-vention. Hierzu stehen zahlreiche etablierte, operative und interventionelle Therapieme-thoden zur Verf{\"u}gung. In manchen F{\"a}llen stoßen die etablierten Techniken jedoch an ihre Grenzen. Bei Patienten mit schwerwiegenden Komorbidit{\"a}ten oder im Rahmen neuer me-dizinischer Verfahren sind Innovationen gefragt. Die Grundidee der vorliegenden Arbeit ist die Entwicklung einer biotechnologischen Therapieoption zur Versorgung gastrointesti-naler Hohlorganperforationen. Methoden: Zur Durchf{\"u}hrung einer Machbarkeitsstudie wurden zehn G{\"o}ttinger Mi-nischweine in zwei Gruppen mit jeweils 5 Tieren aufgeteilt. Den Tieren der Experimental-gruppe wurden Hautbiopsien entnommen und daraus Fibroblasten isoliert, welche vo-r{\"u}bergehend konserviert wurden. Unter Verwendung von azellularisiertem Schweinedarm erfolgte die Herstellung von Implantaten nach den Prinzipien des Tissue Engineerings. Die Tiere beider Gruppen wurden einer Minilaparotomie und einer ca. 3cm-Inzision der Ma-genvorderwand unterzogen. Die anschließende Versorgung wurde in der Experimental-gruppe durch Implantation der neuartigen Konstrukte erzielt. In der Kontrollgruppe wur-de im Sinne des Goldstandards eine konventionelle Naht durchgef{\"u}hrt. Anschließend wurden die Tiere f{\"u}r vier Wochen beobachtet. Eine bzw. zwei Wochen nach dem pri-m{\"a}ren Eingriff wurde bei allen Tieren beider Gruppen eine Laparoskopie bzw. Gastrosko-pie durchgef{\"u}hrt. Am Ende der klinischen Observationsphase wurden die Versuchstiere get{\"o}tet und die entsprechenden Magenareale zur histologischen Untersuchung explantiert. Ergebnisse: Die Herstellung der Implantate konnte auf der Basis standardisierter zellbio-logischer Methoden problemlos etabliert werden. Alle Tiere beider Gruppen {\"u}berlebten den Prim{\"a}reingriff sowie das vierw{\"o}chige Nachbeobachtungsintervall und zeigten dabei keine klinischen Zeichen m{\"o}glicher Komplikationen. Die durchgef{\"u}hrten Laparoskopien und Gastroskopien ergaben bei keinem der Tiere Hinweise auf Leckagen oder lokale Infek-tionsprozesse. Die histologische Aufarbeitung zeigte im Bereich des urspr{\"u}nglichen De-fekts eine bindegewebige {\"U}berbr{\"u}ckung sowie ein beginnendes Remodeling der Magen-schleimhaut in beiden Gruppen. Schlussfolgerungen: Durch die Verkn{\"u}pfung von Einzelprozessen der Zellkultur und dem Großtier-OP konnte ein neues Verfahren zum Verschluss gastrointestinaler Defekt erfolgreich demonstriert und etabliert werden. Das Projekt konnte reibungslos durchge-f{\"u}hrt werden und lieferte Ergebnisse, die dem Goldstandard nicht unterlegen waren. Auf-grund der kleinen Fallzahl und weiterer methodischer Limitationen sind jedoch nur einge-schr{\"a}nkt Schlussfolgerungen m{\"o}glich, weshalb die Durchf{\"u}hrung gr{\"o}ßerer und gut geplan-ter Studien notwendig ist. Die Erkenntnisse dieser Pilotstudie liefern eine solide Basis f{\"u}r die Planung weiterf{\"u}hrender Untersuchungen.},
  subject      = {Magenkrankheit},
  language  = {de}
}