Interaction of extracellular S100A4 with RAGE prompts prometastatic activation of A375 melanoma cells.

S100A4, a member of the S100 protein family of EF-hand calcium-binding proteins, is overexpressed in various tumour entities, including melanoma, and plays an important role in tumour progression. Several studies in epithelial and mesenchymal tumours revealed a correlation between extracellular S100A4 and metastasis. However, exact mechanisms how S100A4 stimulates metastasis in melanoma are still unknown. From a pilot experiment on baseline synthesis and secretion of S100A4 in human melanoma cell lines, which are in broad laboratory use, A375 wild-type cells and, additionally, newly generated A375 cell lines stably transfected with human S100A4 (A375-hS100A4) or human receptor for advanced glycation endproducts (A375-hRAGE), were selected to investigate the influence of extracellular S100A4 on cell motility, adhesion, migration and invasion in more detail. We demonstrated that A375 cells actively secrete S100A4 in the extracellular space via an endoplasmic reticulum-Golgi-dependent pathway. S100A4 overexpression and secretion resulted in prometastatic activation of A375 cells. Moreover, we determined the influence of S100A4-RAGE interaction and its blockade on A375, A375-hS100A4, A375-hRAGE cells, and showed that interaction of RAGE with extracellular S100A4 contributes to the observed activation of A375 cells. This investigation reveals additional molecular targets for therapeutic approaches aiming at blockade of ligand binding to RAGE or RAGE signalling to inhibit melanoma metastasis.

Extracellular S100A4 affects endothelial cell integrity and stimulates transmigration of A375 melanoma cells.

High extracellular S100A4 level proves a specific characteristic of some cancer cases, including malignant melanoma. Concerning the latter, extracellular S100A4 in an autocrine manner was shown to promote prometastatic activation of A375 cells by interaction with the receptor for advanced glycation endproducts (RAGE). We hypothesized that interaction of extracellular S100A4 with RAGE in a paracrine manner will affect endothelial cell (EC) integrity thus further promoting melanoma metastasis. We investigated the influence of recombinant and cell (A375)-derived S100A4 on junction protein expression and EC (hCMEC/D3) integrity by measuring transendothelial electrical resistance (TEER). Decrease of TEER and diminished expression of both occludin and VE-cadherin revealed the loss of EC integrity. Transmigration of transgenic A375 cells (A375-hS100A4/A375-hRAGE) through the EC monolayer was significantly higher compared to wild-type A375 cells, and was substantially decreased by sRAGE. A pilot study in mice, intracardially injected with A375-hS100A4 or A375-hRAGE cells, showed lower survival rates and a higher incidence of metastases compared to wild-type A375 cells. Tumor development was mostly located in the brain, bones, and ovaries. These findings provide further evidence on extracellular S100A4 as paracrine mediator of prometastatic endothelial dysfunction involving its interaction with RAGE.

Metastatic potential of B16-F10 melanoma cells is enhanced by extracellular S100A4 derived from RAW264.7 macrophages.

S100A4, synthesized and secreted from both tumor and stroma cells, modulates an aggressive tumor phenotype in various cancers by intracellular and extracellular interactions which are not completely understood. Because of the high content of tumor-associated macrophages in melanoma, here, a syngeneic model (coculture of mouse B16-F10 melanoma cells (Mel) and RAW264.7 macrophages (Mϕ); administration (i.v.) of Mel and Mϕ/Mel in NMRI nu/nu mice) was used to investigate synthesis and secretion of (a) S100A4, (b) S100A4-mediated signaling and activation of NFκB, and (c) S100A4-mediated modulation of Mel invasiveness in vitro (transwell assay, transwell matrigel assay) and in vivo (metastatic lung colonization), respectively. In this model substantial S100A4 synthesis and secretion is demonstrated in Mϕ. Macrophage-derived S100A4 promotes Mel invasiveness in a paracrine manner in vitro, which is further substantiated in control experiments using recombinant human S100A4 and Mel stably transfected with mouse S100A4. Moreover, the participation of S100A4-mediated signaling, e.g., via the receptor for advanced glycation endproducts (RAGE), resulting in activation of NFκB was demonstrated in all experimental settings. Finally, we demonstrated that interaction of macrophage-derived S100A4 with Mel results in increased metastatic lung colonization in vivo.

Copper distribution in German vineyards and its impact on soil organisms - Dataset of physical, chemical and biological soil parameters of a field survey from 2010 to 2014.

The use of copper-containing fungicides in plant protection has a long history and is today widespread in both organic and conventional agriculture in Germany. The treatments are primarily used to control plant diseases such as downy mildew in vines and hops, collar rot and canker, and apple scab in fruit trees. The regularly re-approval of copper as a pesticide in the European Union is always accompanied by critical discussions about the toxic effects of copper on soil organisms, especially earthworms. This results in the need for independent advice on ecotoxicological risks with field data for the authorities involved in the regulation of copper-containing pesticides. Based on the EU's regulation 1107/2009/EC, the current approval of the active ingredient copper is limited until 2025 and has been included on the list of substitution candidates (article 24) due to its persistency. This category requires a comparative assessment under article 50 with alternatives, mainly less toxic fungicides or resistant cultivars. This data set reflects the spectrum of copper load situation in German vineyards and can be used for risk assessment of artificially applied copper on earthworm and microbial communities in vineyard soils and even other agricultural soils based on field data. It contains 78 sampling areas in total on 10 German quality wine-growing regions. At each sampling area soils of four diagonal sampling points (4 × 0.25 m2) were excavated. In sum, soils from 312 sampling points were collected from the top 20 cm soil depth. The samples were collected in April and October between 2010 and 2014. This survey in German wine-growing regions includes following parameters: Soil data: soil texture (sand, clay, silt), pH-value, organic matter content, element concentrations of nutrient and heavy metals (As, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V, Zn), mobile ("bioavailable") Cu contents extracted with 1 M NH4NO3 and 0.001 M CaCl2. Earthworm data: ecological group, taxa, development stage (adult, juvenile), abundance (number of individuals per 0.25 m2), biomass (g per 0.25 m2 FM), element concentration of earthworm tissue of environmentally relevant elements (As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn). Functional microbial community data: long term soil respiration, microbial biomass, metabolic quotient, dehydrogenase activity.

Artificial Nesting Hills Promote Wild Bees in Agricultural Landscapes.

The availability of nesting resources influences the persistence and survival of bee communities. Although a positive effect of artificial nesting structures has frequently been shown for aboveground cavity-nesting wild bees, studies on below ground-nesting bees are rare. Artificial nesting hills designed to provide nesting habitats for ground-nesting bees were therefore established within the BienABest project in 20 regions across Germany. Wild bee communities were monitored for two consecutive years, accompanied by recordings of landscape and abiotic nest site variables. Bee activity and species richness increased from the first to the second year after establishment; this was particularly pronounced in landscapes with a low cover of semi-natural habitat. The nesting hills were successively colonized, indicating that they should exist for many years, thereby promoting a species-rich bee community. We recommend the construction of nesting hills on sun-exposed sites with a high thermal gain of the substrate because the bees prefer south-facing sites with high soil temperatures. Although the soil composition of the nesting hills plays a minor role, we suggest using local soil to match the needs of the local bee community. We conclude that artificial nesting structures for ground-nesting bees act as a valuable nesting resource for various bee species, particularly in highly degraded landscapes. We offer a construction and maintenance guide for the successful establishment of nesting hills for bee conservation.

Restructuring the clinical curriculum at University Medical Center Göttingen: effects of distance teaching on students' satisfaction and learning outcome.

Introduction: In summer term 2020, the clinical phase of the undergraduate medical curriculum at University Medical Center Göttingen was restructured since distance teaching had to be used predominantly due to contact restrictions during the COVID-19 pandemic. This paper investigates the impact of restructuring the clinical curriculum on medical students' satisfaction and learning outcomes. Methods: In each cohort, the 13-week curriculum was divided into two parts: During the first 9 weeks, factual knowledge was imparted using distance teaching by means of a modified inverted classroom approach. This was followed by a 4-week period of adapted classroom teaching involving both real and virtual patients in order to train students' practical skills. The evaluation of the 21 clinical modules comprised students' satisfaction with distance teaching as well as students' learning outcome. The latter was assessed by means of comparative self-assessment (CSA) gain and the results of the module exams, respectively. Data of summer term 2020 (= distance teaching, DT) were compared with respective data of winter term 2019/20 (= classroom teaching, CT) and analysed for differences and correlations. Results: Response rates of evaluations were 51.3% in CT and 19.3% in DT. There was no significant difference between mean scores in module exams in CT and DT, respectively. However, CSA gain was significantly lower in DT (p=0.047) compared with CT. Further analyses revealed that CSA gain depended on the time point of data collection: CSA gain was lower the more time had passed since the end of a specific module. Moreover, we found positive correlations between CSA gain and students' satisfaction with various aspects of distance teaching, particularly with "communication between teachers and students" (rho=0.674; p=0.002). Discussion and conclusions: Although some limitations and confounding factors have to be taken into account (such as evaluation response rates, assessment time points, and proportion of familiar items in module exams), the following recommendations can be derived from our findings: A valid assessment of students' learning outcome by means of exam results requires that as few exam items as possible are familiar to the students. CSA gain seems to be valid if assessment time points are standardised and not contaminated by students' learning activities for other modules. Good communication between teachers and students may contribute to increase students' satisfaction with distance teaching.

Metabolomics Approaches for Analyzing Effects of Geographic and Environmental Factors on the Variation of Root Essential Oils of Ferula assa-foetida L.

Environmental factors shape the production and accumulation processes of plant secondary metabolites in medical and aromatic plants and thus their pharmacological and biological activity. Using an environmental metabolomics approach, we determined chemotypes and specific compounds on the basis of essential oils (EOs) from roots of 10 Iranian Ferula assa-foetida L. populations and related them to geographical, climate, and edaphic data. GC-MS revealed three distinct chemotypes characterized by (I) monoterpenes and Z-1-propenyl sec-butyl disulfide; (II) eudesmane sesquiterpenoids and α-agarofuran; and (III) Z- and E-1-propenyl sec-butyl disulfide. NIRS measurements indicated a similar but less distinct pattern. Structural equation models showed that EO constituents and content were directly influenced by edaphic factors (texture, pH, and iron, potassium, and aluminum content) and temperature and predominantly indirectly by latitude, longitude, and altitude. Predicting EO constituents or chemotypes by geographical, climate, and soil factors can be used in F. assa-foetida to select populations with specific EO characteristics.

Variation of Secondary Metabolite Profile of Zataria multiflora Boiss. Populations Linked to Geographic, Climatic, and Edaphic Factors.

Geographic location and connected environmental and edaphic factors like temperature, rainfall, soil type, and composition influence the presence and the total content of specific plant compounds as well as the presence of a certain chemotype. This study evaluated whether geographic, edaphic, and climatic information can be utilized to predict the presence of specific compounds from medicinal or aromatic plants. Furthermore, we tested rapid analytical methods based on near infrared spectroscopy (NIR) coupled with gas chromatography/flame ionization (GC/FID) and gas chromatography/mass spectrometry (GC/MS) analytical methods for characterization and classification metabolite profiling of Zataria multiflora Boiss. populations. Z. multiflora is an aromatic, perennial plant with interesting pharmacological and biological properties. It is widely dispersed in Iran as well as in Pakistan and Afghanistan. Here, we studied the effect of environmental factors on essential oil (EO) content and the composition and distribution of chemotypes. Our results indicate that this species grows predominantly in areas rich in calcium, iron, potassium, and aluminum, with mean rainfall of 40.46 to 302.72 mm·year-1 and mean annual temperature of 14.90°C to 28.80°C. EO content ranged from 2.75% to 5.89%. Carvacrol (10.56-73.31%), thymol (3.51-48.12%), linalool (0.90-55.38%), and p-cymene (1.66-13.96%) were the major constituents, which classified 14 populations into three chemotypes. Corresponding to the phytochemical cluster analysis, the hierarchical cluster analysis (HCA) based on NIR data also recognized the carvacrol, thymol, and linalool chemotypes. Hence, NIR has the potential to be applied as a useful tool to determine rapidly the chemotypes of Z. multiflora and similar herbs. EO and EO constituent content correlated with different geographic location, climate, and edaphic factors. The structural equation models (SEMs) approach revealed direct effects of soil factors (texture, phosphor, pH) and mostly indirect effects of latitude and altitude directly affecting, e.g., soil factors. Our approach of identifying environmental predictors for EO content, chemotype or presence of high amounts of specific compounds can help to select regions for sampling plant material with the desired chemical profile for direct use or for breeding.