TY - JOUR A1 - Meyer, Till Jasper A1 - Scherzad, Agmal A1 - Moratin, Helena A1 - Gehrke, Thomas Eckert A1 - Killisperger, Julian A1 - Hagen, Rudolf A1 - Wohlleben, Gisela A1 - Polat, Bülent A1 - Dembski, Sofia A1 - Kleinsasser, Norbert A1 - Hackenberg, Stephan T1 - The radiosensitizing effect of zinc oxide nanoparticles in sub-cytotoxic dosing is associated with oxidative stress in vitro JF - Materials N2 - Radioresistance is an important cause of head and neck cancer therapy failure. Zinc oxide nanoparticles (ZnO-NP) mediate tumor-selective toxic effects. The aim of this study was to evaluate the potential for radiosensitization of ZnO-NP. The dose-dependent cytotoxicity of ZnO-NP\(_{20 nm}\) and ZnO-NP\(_{100 nm}\) was investigated in FaDu and primary fibroblasts (FB) by an MTT assay. The clonogenic survival assay was used to evaluate the effects of ZnO-NP alone and in combination with irradiation on FB and FaDu. A formamidopyrimidine-DNA glycosylase (FPG)-modified single-cell microgel electrophoresis (comet) assay was applied to detect oxidative DNA damage in FB as a function of ZnO-NP and irradiation exposure. A significantly increased cytotoxicity after FaDu exposure to ZnO-NP\(_{20 nm}\) or ZnO-NP\(_{100 nm}\) was observed in a concentration of 10 µg/mL or 1 µg/mL respectively in 30 µg/mL of ZnO-NP\(_{20 nm}\) or 20 µg/mL of ZnO-NP\(_{100 nm}\) in FB. The addition of 1, 5, or 10 µg/mL ZnO-NP\(_{20 nm}\) or ZnO-NP\(_{100 nm}\) significantly reduced the clonogenic survival of FaDu after irradiation. The sub-cytotoxic dosage of ZnO-NP\(_{100 nm}\) increased the oxidative DNA damage compared to the irradiated control. This effect was not significant for ZnO-NP\(_{20 nm}\). ZnO-NP showed radiosensitizing properties in the sub-cytotoxic dosage. At least for the ZnO-NP\(_{100 nm}\), an increased level of oxidative stress is a possible mechanism of the radiosensitizing effect. KW - zinc oxide nanoparticles KW - irradiation KW - oxidative DNA damage KW - head and neck squamous cell carcinoma Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-193897 SN - 1996-1944 VL - 12 IS - 24 ER - TY - JOUR A1 - Stefanakis, Mona A1 - Bassler, Miriam C. A1 - Walczuch, Tobias R. A1 - Gerhard-Hartmann, Elena A1 - Youssef, Almoatazbellah A1 - Scherzad, Agmal A1 - Stöth, Manuel Bernd A1 - Ostertag, Edwin A1 - Hagen, Rudolf A1 - Steinke, Maria R. A1 - Hackenberg, Stephan A1 - Brecht, Marc A1 - Meyer, Till Jasper T1 - The impact of tissue preparation on salivary gland tumors investigated by Fourier-transform infrared microspectroscopy JF - Journal of Clinical Medicine N2 - Due to the wide variety of benign and malignant salivary gland tumors, classification and malignant behavior determination based on histomorphological criteria can be difficult and sometimes impossible. Spectroscopical procedures can acquire molecular biological information without destroying the tissue within the measurement processes. Since several tissue preparation procedures exist, our study investigated the impact of these preparations on the chemical composition of healthy and tumorous salivary gland tissue by Fourier-transform infrared (FTIR) microspectroscopy. Sequential tissue cross-sections were prepared from native, formalin-fixed and formalin-fixed paraffin-embedded (FFPE) tissue and analyzed. The FFPE cross-sections were dewaxed and remeasured. By using principal component analysis (PCA) combined with a discriminant analysis (DA), robust models for the distinction of sample preparations were built individually for each parotid tissue type. As a result, the PCA-DA model evaluation showed a high similarity between native and formalin-fixed tissues based on their chemical composition. Thus, formalin-fixed tissues are highly representative of the native samples and facilitate a transfer from scientific laboratory analysis into the clinical routine due to their robust nature. Furthermore, the dewaxing of the cross-sections entails the loss of molecular information. Our study successfully demonstrated how FTIR microspectroscopy can be used as a powerful tool within existing clinical workflows. KW - formalin KW - fixation KW - tissue preparation KW - salivary gland neoplasia KW - FTIR spectroscopy KW - principal component analysis KW - discriminant analysis Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304887 SN - 2077-0383 VL - 12 IS - 2 ER - TY - JOUR A1 - Sivarajan, Rinu A1 - Kessie, David Komla A1 - Oberwinkler, Heike A1 - Pallmann, Niklas A1 - Walles, Thorsten A1 - Scherzad, Agmal A1 - Hackenberg, Stephan A1 - Steinke, Maria T1 - Susceptibility of Human Airway Tissue Models Derived From Different Anatomical Sites to Bordetella pertussis and Its Virulence Factor Adenylate Cyclase Toxin JF - Frontiers in Cellular and Infection Microbiology N2 - To study the interaction of human pathogens with their host target structures, human tissue models based on primary cells are considered suitable. Complex tissue models of the human airways have been used as infection models for various viral and bacterial pathogens. The Gram-negative bacterium Bordetella pertussis is of relevant clinical interest since whooping cough has developed into a resurgent infectious disease. In the present study, we created three-dimensional tissue models of the human ciliated nasal and tracheo-bronchial mucosa. We compared the innate immune response of these models towards the B. pertussis virulence factor adenylate cyclase toxin (CyaA) and its enzymatically inactive but fully pore-forming toxoid CyaA-AC\(^-\). Applying molecular biological, histological, and microbiological assays, we found that 1 µg/ml CyaA elevated the intracellular cAMP level but did not disturb the epithelial barrier integrity of nasal and tracheo-bronchial airway mucosa tissue models. Interestingly, CyaA significantly increased interleukin 6, interleukin 8, and human beta defensin 2 secretion in nasal tissue models, whereas tracheo-bronchial tissue models were not significantly affected compared to the controls. Subsequently, we investigated the interaction of B. pertussis with both differentiated primary nasal and tracheo-bronchial tissue models and demonstrated bacterial adherence and invasion without observing host cell type-specific significant differences. Even though the nasal and the tracheo-bronchial mucosa appear similar from a histological perspective, they are differentially susceptible to B. pertussis CyaA in vitro. Our finding that nasal tissue models showed an increased innate immune response towards the B. pertussis virulence factor CyaA compared to tracheo-bronchial tissue models may reflect the key role of the nasal airway mucosa as the first line of defense against airborne pathogens. KW - human nasal epithelial cells KW - human tracheo-bronchial epithelial cells KW - human airway mucosa tissue models KW - adenylate cyclase toxin KW - Bordetella pertussis Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-253302 SN - 2235-2988 VL - 11 ER - TY - JOUR A1 - Meyer, Till Jasper A1 - Gerhard-Hartmann, Elena A1 - Lodes, Nina A1 - Scherzad, Agmal A1 - Hagen, Rudolf A1 - Steinke, Maria A1 - Hackenberg, Stephan T1 - Pilot study on the value of Raman spectroscopy in the entity assignment of salivary gland tumors JF - PLoS One N2 - Background The entity assignment of salivary gland tumors (SGT) based on histomorphology can be challenging. Raman spectroscopy has been applied to analyze differences in the molecular composition of tissues. The aim of this study was to evaluate the suitability of RS for entity assignment in SGT. Methods Raman data were collected in deparaffinized sections of pleomorphic adenomas (PA) and adenoid cystic carcinomas (ACC). Multivariate data and chemometric analysis were completed using the Unscrambler software. Results The Raman spectra detected in ACC samples were mostly assigned to nucleic acids, lipids, and amides. In a principal component-based linear discriminant analysis (LDA) 18 of 20 tumor samples were classified correctly. Conclusion In this proof of concept study, we show that a reliable SGT diagnosis based on LDA algorithm appears possible, despite variations in the entity-specific mean spectra. However, a standardized workflow for tissue sample preparation, measurement setup, and chemometric algorithms is essential to get reliable results. KW - Head and neck cancers KW - salivary gland tumors KW - salivary glands KW - cancers and neoplasms KW - malignant tumors KW - lipids KW - raman spectroscopy KW - surgical oncology Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-264736 VL - 16 IS - 9 ER -