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The aim of this study was to investigate the diagnostic accuracy and reader confidence for late-gadolinium enhancement (LGE) detection of a novel free-breathing, image-based navigated 3D whole-heart LGE sequence with fat–water separation, compared to a free-breathing motion-corrected 2D LGE sequence in patients with ischemic and non-ischemic cardiomyopathy. Cardiac MRI patients including the respective sequences were retrospectively included. Two independent, blinded readers rated image quality, depiction of segmental LGE and documented acquisition time, SNR, CNR and amount of LGE. Results were compared using the Friedman or the Kruskal–Wallis test. For LGE rating, a jackknife free-response receiver operating characteristic analysis was performed with a figure of merit (FOM) calculation. Forty-two patients were included, thirty-two were examined with a 1.5 T-scanner and ten patients with a 3 T-scanner. The mean acquisition time of the 2D sequence was significantly shorter compared to the 3D sequence (07:12 min vs. 09:24 min; p

Objectives To investigate the efficacy of an in-line non-rigid motion-compensated reconstruction (NRC) in an image-navigated high-resolution three-dimensional late gadolinium enhancement (LGE) sequence with Dixon water–fat separation, in a clinical setting. Methods Forty-seven consecutive patients were enrolled prospectively and examined with 1.5 T MRI. NRC reconstructions were compared to translational motion-compensated reconstructions (TC) of the same datasets in overall and different sub-category image quality scores, diagnostic confidence, contrast ratios, LGE pattern, and semiautomatic LGE quantification. Results NRC outperformed TC in all image quality scores (p < 0.001 to 0.016; e.g., overall image quality 5/5 points vs. 4/5). Overall image quality was downgraded in only 23% of NRC datasets vs. 53% of TC datasets due to residual respiratory motion. In both reconstructions, LGE was rated as ischemic in 11 patients and non-ischemic in 10 patients, while it was absent in 26 patients. NRC delivered significantly higher LGE-to-myocardium and blood-to-myocardium contrast ratios (median 6.33 vs. 5.96, p < 0.001 and 4.88 vs. 4.66, p < 0.001, respectively). Automatically detected LGE mass was significantly lower in the NRC reconstruction (p < 0.001). Diagnostic confidence was identical in all cases, with high confidence in 89% and probable in 11% datasets for both reconstructions. No case was rated as inconclusive. Conclusions The in-line implementation of a non-rigid motion-compensated reconstruction framework improved image quality in image-navigated free-breathing, isotropic high-resolution 3D LGE imaging with undersampled spiral-like Cartesian sampling and Dixon water–fat separation compared to translational motion correction of the same datasets. The sharper depictions of LGE may lead to more accurate measures of LGE mass. Key Points • 3D LGE imaging provides high-resolution detection of myocardial scarring. • Non-rigid motion correction provides better image quality in cardiac MRI. • Non-rigid motion correction may lead to more accurate measures of LGE mass.

Simple Summary The chorioallantoic membrane (CAM) is a highly vascularized membrane found in avian eggs. Tumor cell lines can be grown on the CAM, which allows for the further analyses of the tumor grafts afterwards. We investigated the biological and growth characteristics of two breast cancer cell lines that resemble two biologically different breast cancer subgroups. Known biological features of the more aggressive breast cancer cell line were clearly confirmed in vitro and in the CAM model. Furthermore, the tissue-based pathological variables assessed in the CAM model were similar to those of the mouse xenografts and human patient tumor tissue. We suggest this in vivo model to be a reliable alternative for breast cancer research to reduce murine animal experiments. Abstract The chorioallantoic membrane (CAM) assay is an alternative in vivo model that allows for minimally invasive research of cancer biology. Using the CAM assay, we investigated phenotypical and functional characteristics (tumor grade, mitosis rate, tumor budding, hormone receptor (HR) and HER2 status, Ki-67 proliferation index) of two breast cancer cell lines, MCF-7 and MDA-MB-231, which resemble the HR+ (luminal) and triple-negative breast cancer (TNBC) subgroups, respectively. Moreover, the CAM results were directly compared with murine MCF-7- and MDA-MB-231-derived xenografts and human patient TNBC tissue. Known phenotypical and biological features of the aggressive triple-negative breast cancer cell line (MDA-MB-231) were confirmed in the CAM assay, and mouse xenografts. Furthermore, the histomorphological and immunohistochemical variables assessed in the CAM model were similar to those in human patient tumor tissue. Given the confirmation of the classical biological and growth properties of breast cancer cell lines in the CAM model, we suggest this in vivo model to be a reliable alternative test system for breast cancer research to reduce murine animal experiments.

In cancer, the activating transcription factor 2 (ATF2) has pleiotropic functions in cellular responses to growth stimuli, damage, or inflammation. Due to only limited studies, the significance of ATF2 in colorectal cancer (CRC) is not well understood. We report that low ATF2 levels correlated with worse prognosis and tumor aggressiveness in CRC patients. NanoString gene expression and ChIP analysis confirmed trophoblast cell surface antigen 2 (TROP2) as a novel inhibitory ATF2 target gene. This inverse correlation was further observed in primary human tumor tissues. Immunostainings revealed that high intratumoral heterogeneity for ATF2 and TROP2 expression was sustained also in liver metastasis. Mechanistically, our in vitro data of CRISPR/Cas9-generated ATF2 knockout (KO) clones revealed that high TROP2 levels were critical for cell de-adhesion and increased cell migration without triggering EMT. TROP2 was enriched in filopodia and displaced Paxillin from adherens junctions. In vivo imaging, micro-computer tomography, and immunostainings verified that an ATF2KO/TROP2high status triggered tumor invasiveness in in vivo mouse and chicken xenograft models. In silico analysis provided direct support that ATF2low/TROP2high expression status defined high-risk CRC patients. Finally, our data demonstrate that ATF2 acts as a tumor suppressor by inhibiting the cancer driver TROP2. Therapeutic TROP2 targeting might prevent particularly the first steps in metastasis, i.e., the de-adhesion and invasion of colon cancer cells.

Simple Summary The formation of metastasis is not only intricately orchestrated by cancer cells but is also affected by the surrounding extracellular matrix (ECM). The barrier function of the ECM represents an obstacle that cancer cells have to overcome to disseminate from the primary tumor to form metastasis in distant organs. Here, we demonstrate an approach to studying the remodeling of a collagen-rich ECM by colorectal tumor cells using multiphoton microscopy (MPM). This approach allows the analysis of the invasion front of tumors grown on the CAM in 3D. MPM is superior to conventional histology, which is limited to 2D analysis and needs extensive tissue preparation. Abstract Cancer cells facilitate tumor growth by creating favorable tumor micro-environments (TME), altering homeostasis and immune response in the extracellular matrix (ECM) of surrounding tissue. A potential factor that contributes to TME generation and ECM remodeling is the cytoskeleton-associated human death-associated protein kinase 1 (DAPK1). Increased tumor cell motility and de-adhesion (thus, promoting metastasis), as well as upregulated plasminogen-signaling, are shown when functionally analyzing the DAPK1 ko-related proteome. However, the systematic investigation of how tumor cells actively modulate the ECM at the tissue level is experimentally challenging since animal models do not allow direct experimental access while artificial in vitro scaffolds cannot simulate the entire complexity of tissue systems. Here, we used the chorioallantoic membrane (CAM) assay as a natural, collagen-rich tissue model in combination with all-optical experimental access by multiphoton microscopy (MPM) to study the ECM remodeling potential of colorectal tumor cells with and without DAPK1 in situ and even in vivo. This approach demonstrates the suitability of the CAM assay in combination with multiphoton microscopy for studying collagen remodeling during tumor growth. Our results indicate the high ECM remodeling potential of DAPK1 ko tumor cells at the tissue level and support our findings from proteomics.

The epithelial–mesenchymal transition (EMT) is associated with tumor aggressiveness and increased invasion, migration, metastasis, angiogenesis, and drug resistance. Although the HCT116 p21-/- cell line is well known for its EMT-associated phenotype, with high Vimentin and low E-cadherin protein levels, the gene signature of this rather intermediate EMT-like cell line has not been determined so far. In this work, we present a robust molecular and bioinformatics analysis, to reveal the associated gene expression profile and its correlation with different types of colorectal cancer tumors. We compared the quantitative signature obtained with the NanoString platform with the expression profiles of colorectal cancer (CRC) Consensus Molecular Subtypes (CMS) as identified, and validated the results in a large independent cohort of human tumor samples. The expression signature derived from the p21-/- cells showed consistent and reliable numbers of upregulated and downregulated genes, as evaluated with two machine learning methods against the four CRC subtypes (i.e., CMS1, 2, 3, and 4). High concordance was found between the upregulated gene signature of HCT116 p21-/- cells and the signature of the CMS4 mesenchymal subtype. At the same time, the upregulated gene signature of the native HCT116 cells was similar to that of CMS1. Using a multivariate Cox regression model to analyze the survival data in the CRC tumor cohort, we selected genes that have a predictive risk power (with a significant gene risk incidence score). A set of genes of the mesenchymal signature was proven to be significantly associated with poor survival, specifically in the CMS4 CRC human cohort. We suggest that the gene signature of HCT116 p21-/- cells could be a suitable metric for mechanistic studies regarding the CMS4 signature and its functional consequences in CRC. Moreover, this model could help to discover the molecular mechanisms of intermediate EMT, which is known to be associated with extraordinarily high stemness and drug resistance., R.S.-S. was supported by the Emerging Fields Initiative ‘Cell Cycle in Disease and Regeneration’ (CYDER) of the Friedrich Alexander University (Erlangen-Nürnberg, Germany). This article is partly based upon work from COST Action CA17118 TRANSCOLONCAN, supported by COST (European Cooperation in Science and Technology, www.cost.eu, last accessed 20 December 2021). The JDLR research group is supported by the Spanish Government, Instituto de Salud Carlos III (ISCiii, AES project PI18/00591) co-funded by FEDER/ERDF (European Regional Development Fund).

Objectives To evaluate an image-navigated isotropic high-resolution 3D late gadolinium enhancement (LGE) prototype sequence with compressed sensing and Dixon water-fat separation in a clinical routine setting. Material and methods Forty consecutive patients scheduled for cardiac MRI were enrolled prospectively and examined with 1.5 T MRI. Overall subjective image quality, LGE pattern and extent, diagnostic confidence for detection of LGE, and scan time were evaluated and compared to standard 2D LGE imaging. Robustness of Dixon fat suppression was evaluated for 3D Dixon LGE imaging. For statistical analysis, the non-parametric Wilcoxon rank sum test was performed. Results LGE was rated as ischemic in 9 patients and non-ischemic in 11 patients while it was absent in 20 patients. Image quality and diagnostic confidence were comparable between both techniques (p = 0.67 and p = 0.66, respectively). LGE extent with respect to segmental or transmural myocardial enhancement was identical between 2D and 3D (water-only and in-phase). LGE size was comparable (3D 8.4 ± 7.2 g, 2D 8.7 ± 7.3 g, p = 0.19). Good or excellent fat suppression was achieved in 93% of the 3D LGE datasets. In 6 patients with pericarditis, the 3D sequence with Dixon fat suppression allowed for a better detection of pericardial LGE. Scan duration was significantly longer for 3D imaging (2D median 9:32 min vs. 3D median 10:46 min, p = 0.001). Conclusion The 3D LGE sequence provides comparable LGE detection compared to 2D imaging and seems to be superior in evaluating the extent of pericardial involvement in patients suspected with pericarditis due to the robust Dixon fat suppression. Key Points • Three-dimensional LGE imaging provides high-resolution detection of myocardial scarring. • Robust Dixon water-fat separation aids in the assessment of pericardial disease. • The 2D image navigator technique enables 100% respiratory scan efficacy and permits predictable scan times.

In order to estimate boundary layer properties and flow separation within the mid-fidelity aerodynamics code UPM, fast, simple, and robust methods are required. Following a review of suitable methods, two approaches were selected and implemented: stripwise analysis using integral boundary layer methods for lifting surfaces and a simplified analysis based on flat-plate analogy for arbitrary non-lifting bodies. The implemented methods were validated for airfoil, wing, fuselage, and rotor simulations. The results show that the implemented methods accomplish the original purpose of estimating friction forces for bodies in attached flows and detecting regions probably dominated by flow separations. However, they neither model detached flows nor predict their impact on body forces and moments.

In this work we present analysis and design results of NLF airfoils and wings for long range aircraft. Extension of wing laminar boundary layer for long range transonic aircraft design is limited by large Reynolds numbers and large wing leading edge sweeps. To explore the NLF potential different swept tapered 2.75D airfoils were designed using the CATNLF method. CATNLF allows attenuating the crossflow instability amplification in the nose region for wings with long range sweeps and Reynolds numbers. Crossflow instability is reduced to a level so that in the nose region NLF is achieved without requiring suction. For 3D studies the long range NASA NLF common research model CRM-NLF is used. Stability analysis and further design is performed using the CRM-NLF wing geometry. Linear stability results obtained with the eN method for the 2.75D and 3D cases show that that theextent of laminar flow for regions downstream of the nose is strongly dependent on the used stability analysis approach. It is shown that using either incompressible or compressible stability analysis together with the currently used assumptions for critical flight N-factor values leads to a significant different potential of laminar extent and wave drag reduction possibilities.

Cracks in silicon solar cells reduce cell efficiency and may lead to critical failures in cell and module production because of breakage. Detecting cracks in an early production stage is, therefore, advisable. Several approaches for crack detection systems have been developed in the past years. In order to compare the system performance, the rating done by the system has to be compared with a reference, i.e., a ground truth defining the crack's presence, position, and/or area. This information can also be used for training of detection algorithms based on supervised learning, e.g., convolutional neural networks. In the present article, we show that finding the ground truth is ambiguous and depends strongly on the operator and the applied metrology. For this end, we apply six crack detection tools to a set of 120 multicrystalline silicon passivated emitter and rear cells that were sorted out in industrial production because of cracks, and compare the human rating of six operators for every tool. The operators’ precision, i.e., the fraction of the contrasts detected as cracks that actually are cracks, ranges from 73% to 100% and their recall, i.e., the fraction of all actual cracks that have been found, from 30% to 92% for all tools and operators. To achieve the highest precision and recall, we suggest rating the images of an optical near-infrared system combined with luminescence imaging by three operators conjointly for the definition of ground truth for the present as well as for larger sample sets.

Hepatocellular carcinoma (HCC) is one of the most common causes for cancer‐related death worldwide with rapidly increasing incidence and mortality rates. As for other types of cancers, also in HCC cancer stem cells (CSCs) are thought to be responsible for tumour initiation, progression and therapy failure. However, as rare subpopulations of tumour tissue, CSCs are difficult to isolate, thus making the development of suitable and reliable model systems necessary. In our study, we generated HepG2 subclones with enriched CSC potential by application of the spheroid formation method and subsequent single‐cell cloning. Analyses in several 2D and 3D cell culture systems as well as a panel of functional assays both in vitro and in vivo revealed that the generated subclones displayed characteristic and sustained features of tumour initiating cells as well as highly aggressive properties related to tumour progression and metastasis. These characteristics could clearly be correlated with the expression of CSC markers that might have prognostic value in the clinical HCC setting. Therefore, we conclude that our CSC enriched HepG2 clones certainly represent suitable model systems to study the role of CSCs during HCC initiation, progression and drug resistance.

Measurement images of solar cells contain information about their material- and process-related quality beyond current-voltage characteristics. This information is currently only partially used because most algorithms look for human-defined image features or defects. Herein, a purely data-driven method is proposed to derive the essential image information in terms of the electrical quality within a comprehensive and meaningful representation. This representation is denoted as the empirical digital twin of the cell. Using it, solar cells can be classified according to their defects visible in the measurement images. For this purpose, a human-in-the-loop approach to efficiently develop a classification scheme is presented. Therefore, a convolutional neural network combining various measurement data of a sample by correlating them with quality parameters is designed. The digital twin is an intermediate representation of the network capturing the quality-relevant defect signatures from the images. Human experts can analyze this representation space to identify defect clusters that relate to different process errors, such as finger interruptions and shunts. How the representations are usable to derive sorting criteria for quality inspection is shown. Finally, how the empirical digital twin and the sorting scheme can be used for segmenting the defects without additional label effort is demonstrated.

Colorectal cancer (CRC) is one of the leading cancer-related causes of death worldwide. Despite the improvement of surgical and chemotherapeutic treatments, as of yet, the disease has not been overcome due to metastasis to distant organs. Hence, it is of great relevance to understand the mechanisms responsible for metastasis initiation and progression and to identify novel metastatic markers for a higher chance of preventing the metastatic disease. The Death-associated protein kinase 1 (DAPK1), recently, has been shown to be a potential candidate for regulating metastasis in CRC. Hence, the aim of the study was to investigate the impact of DAPK1 protein on CRC aggressiveness. Using CRISPR/Cas9 technology, we generated DAPK1-deficient HCT116 monoclonal cell lines and characterized their knockout phenotype in vitro and in vivo. We show that loss of DAPK1 implemented changes in growth pattern and enhanced tumor budding in vivo in the chorioallantoic membrane (CAM) model. Further, we observed more tumor cell dissemination into chicken embryo organs and increased invasion capacity using rat brain 3D in vitro model. The novel identified DAPK1-loss gene expression signature showed a stroma typical pattern and was associated with a gained ability for remodeling the extracellular matrix. Finally, we suggest the DAPK1-ERK1 signaling axis being involved in metastatic progression of CRC. Our results highlight DAPK1 as an anti-metastatic player in CRC and suggest DAPK1 as a potential predictive biomarker for this cancer type.

DLR was involved in the aerodynamic design and evaluation of the innovative high-speed compound helicopter demonstrator RACER, developed under the lead of Airbus Helicopters. This paper presents low-fidelity analyses and optimizations performed to supplement RANS simulations in the design and evaluation process of the RACER wings and tail. A toolchain based on the 3D panel method VSAERO was implemented to quickly perform such tasks. The presented applications include component interaction analyses, optimization of circulation distribution, evaluation of flap efficiency and evaluation of different tail designs. The results helped to gain better understanding of the complex RACER configuration aerodynamics including interaction effects of various components. Moreover, the computational effort could be considerably reduced by the proposed method compared to RANS simulations. Nevertheless, one must be aware of the method restrictions and carefully check whether their application is reasonable for each use case.

Background: Nowadays, breast cancer represents both the most frequently diagnosed type of cancer as well as the leading cause of cancer associated death in women. Clinically, breast cancer tumors can be stratified into four major subgroups based on the expression of estrogen receptors (ER) and progesterone receptors (PR), the proliferation marker Ki67 and the expression/amplification of HER2/neu. Hormone receptor (HR) positive tumors generally have a slightly more favorable prognosis than the other two subgroups and can be treated with agents interfering with hormone signaling. A targeted therapy approach is also applied for HER2/neu amplified tumors by using agents that inhibit HER2/neu. In contrast, patients with triple negative breast cancers (TNBCs), i.e. tumors lacking HR expression as well as HER2/neu amplification, have a fairly poor outcome due to the high aggressiveness of this subgroup, especially if not responding to neoadjuvant therapy. Methods: In our study, we investigated phenotypical and functional characteristics of the two breast cancer cell lines MCF-7 and MDA-MB-231 that resemble the HR+ and the TNBC subgroup, respectively. In vitro, we were specifically interested in the invasiveness of the cells, thus determining their aggressiveness in a 3D spheroid invasion assay. In addition, we applied the in vivo chorioallantoic membrane (CAM) xenograft assay to histologically analyze the tumor growth patterns and evaluate metastasis formation using a human-specific Alu-PCR method and an in vivo imaging system (IVIS). Results: As anticipated, the highly aggressive TNBC cell line MDA-MB-231 generated CAM micro-tumors much larger than those derived of the HR+ MCF-7 cell line. Moreover, we were able to verify different characteristic histological features of TNBC and HR+ tumors in the CAM xenograft model. In this regard, the MDA-MB-231 cells showed the distinct growth pattern of a poorly differentiated adenocarcinoma and a highly infiltrative growth into the CAM with strong tumor budding (clusters of ≤5 cells) at the invasive front. The high tumor budding rate could be correlated to an extremely invasive potential of the TNBC cells in vitro as well as to a strong metastasis formation in the in vivo CAM assay. Conclusion: Our findings suggest that the CAM xenograft assay represents a suitable model to mimic the clinical situation of breast cancer patients. For the first time, we could show that tumor budding is correlated with metastasis formation in this alternative xenograft system. Citation Format: Julienne K. Muenzner, Raphela A. Ranjan, Markus Eckstein, Ramona Erber, Philipp Kunze, Carol I. Geppert, Matthias Ruebner, Tobias Baeuerle, Arndt Hartmann, Regine Schneider-Stock. Tumor budding: A predictor for metastasis in the CAM xenograft model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3699.

BACKGROUND: Small-cell lung cancer (SCLC) is a highly aggressive neoplasm, characterized by early development of metastasis and very poor clinical outcome. The therapeutic possibilities are limited and poorly changed over the past three decades. Enhancer of zeste homolog 2 (EZH2) is a member of the polycomb repressive complex 2. It is involved in epigenetic gene silencing through the trimethylation of H3K27 and it has been identified as a biomarker of aggressive and highly proliferating tumors, emerging as a potential target for cancer therapy. OBJECTIVE: We aimed to correlate the expression profile of the EZH2 and H3K27me3 proteins in tumor tissues of non-treated SCLC patients with patient's outcome. METHODS: EZH2 and H3K27me3 expression were analyzed by immunohistochemistry in 48 SCLC tumor biopsies. The expression of the markers was quantified in a semi quantitative way and correlated with clinic pathological factors and patients overall survival. To mimic an EZH2 loss, H209 SCLC cells were treated with an EZH2 inhibitor for 48h and the in vivo growth pattern was investigated in the chorioallantoic membrane (CAM) assay. RESULTS: All patients died within one year after diagnosis. There was a heterogeneous expression pattern for EZH2 and H3K27me3. Strong expression of EZH2 and H3K27me3 was observed in appr. 50% of the patients. The Kaplan Meier curve showed a significant association of high expression pattern of EZH2 and shorter overall patient survival time after 12 and 25 weeks of follow up, respectively (p=0.030; p=0.014) Different markers of tumor aggressiveness after EZH2 inhibition were investigated in the CAM model. CONCLUSION: Strong EZH2 and H3K27me3 expression in non-treated SCLC patients was related to worse prognosis. EZH2 inhibitors should be considered in future trials for SCLC. Citation Format: Ana Paula Fernandes, Rita deCassia S Alves, Guilherme Watte, Philipp Kunze, Adriana Vial Roehe, Regine Schneider-Stock. Strong expression of EZH2 and H3K27me3 is associated with poor survival time in small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3713.

In recent years many efforts of researchers and clinicians were made to improve our knowledge of cachexia syndrome. Not only cancer, but also many chronic or end-stage diseases such as AIDS, chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, tuberculosis and Crohn's disease are associated with cachexia, a condition of abnormally low weight, weakness, and general bodily decline which deteriorates quality of life and reduces the prognosis of the patients who suffer from it. In the present editorial we will focus cachexia related on cancer and provide some insight into this prognosis-limiting syndrome.

In recent years many efforts of researchers and clinicians were made to improve our knowledge of cachexia syndrome. Not only cancer, but also many chronic or end-stage diseases such as AIDS, chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, tuberculosis and Crohn's disease are associated with cachexia, a condition of abnormally low weight, weakness, and general bodily decline which deteriorates quality of life and reduces the prognosis of the patients who suffer from it. In the present editorial we will focus cachexia related on cancer and provide some insight into this prognosis-limiting syndrome.