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Hypoxia-inducible factors (HIFs) are heterodimeric transcription factors induced in diverse pathophysiological settings. Inhibition of HIF-2α has become a strategy for cancer treatment since the discovery that small molecules, upon binding into a small cavity of the HIF-2α PAS B domain, can alter its conformation and disturb the activity of the HIF dimer complex. Herein, the design, synthesis, and systematic SAR exploration of cycloalkyl[ c ]thiophenes as novel HIF-2α inhibitors are described, providing the first chemotype featuring an alkoxy-aryl scaffold. X-ray data confirmed the ability of these inhibitors to induce perturbation of key amino acids by appropriately presenting key pharmacophoric elements in the hydrophobic cavity. Selected compounds showed inhibition of VEGF-A secretion in cancer cells and prevention of Arg1 expression and activity in IL4-stimulated macrophages. Moreover, in vivo target gene modulation was demonstrated with compound 35r . Thus, the disclosed HIF-2α inhibitors represent valuable tools for investigating selective HIF-2α inhibition and its effect on tumor biology.

Intracellular distribution of drug compounds is dependent on physicochemical characteristics and may have a significant bearing on the extent of target occupancy and, ultimately, drug efficacy. We assessed differences in the physicochemical profiles of MET inhibitors capmatinib, crizotinib, savolitinib, and tepotinib and their effects on cell viability and MET phosphorylation under steady-state and washout conditions (to mimic an open organic system) in a human lung cancer cell line. To examine the differences of the underlying molecular mechanisms at the receptor level, we investigated the residence time at the kinase domain and the cellular target engagement. We found that the ranking of the drugs for cell viability was different under steady-state and washout conditions and that under washout conditions, tepotinib displayed the most potent inhibition of phosphorylated MET. Postwashout effects were correlated with the partitioning of the drug into acidic subcellular compartments such as lysosomes, and the tested MET inhibitors were grouped according to their ability to access lysosomes (crizotinib and tepotinib) or not (capmatinib and savolitinib). Reversible lysosomal retention may represent a valuable intracellular storage mechanism for MET inhibitors, enabling prolonged receptor occupancy in dynamic, open-physiologic systems and may act as a local drug reservoir. The use of washout conditions to simulate open systems and investigate intracellular drug distribution is a useful characterization step that deserves further investigation. SIGNIFICANCE STATEMENT: Generally, determination of potency and receptor occupancy is performed under steady-state conditions. In vivo conditions are more complex due to concentration differences between compartments and equilibrium processes. Experiments under steady state cannot explore effects such as sustained target inhibition. This study has shown that differences between MET inhibitors are observable by applying washout conditions to in vitro assays. This important finding applies to most compound classes and may inspire readers to rethink their assay designs in the future., (Copyright © 2023 The Author(s).)

During humanitarian crises, such as a pandemic, healthcare systems worldwide face unknown challenges. This study aimed to explore and describe the effect of the SARS-CoV-2 pandemic on the needs of non-infected patients and family caregivers in specialist palliative care, using qualitative, semi-structured interviews. Data were analyzed using inductive content analysis, following the framework approach. Thirty-one interviews were conducted with patients/family caregivers (15/16) in palliative care units/specialist palliative home care (21/10) from June 2020 to January 2021. Well-known needs of patients and family caregivers at the end of life remained during the pandemic. Pandemic- dependent themes were (1) implications of the risk of contagion, (2) impact of the restriction of social interactions, (3) effects on the delivery of healthcare, and (4) changes in the relative's role as family caregiver. Restriction on visits limited family caregivers' ability to be present in palliative care units. In specialist palliative home care, family caregivers were concerned about the balance between preserving social contacts at the end of life and preventing infection. Specialist palliative care during a pandemic needs to meet both the well-known needs at the end of life and additional needs in the pandemic context. In particular, attention should be given to the needs and burden of family caregivers, which became more multifaceted with regards to the pandemic.

The recruitment of T cells is a crucial component in the inflammatory cascade of the body. The process involves the transport of T cells through the vascular system and their stable arrest to vessel walls at the site of inflammation, followed by extravasation and subsequent infiltration into tissue. Here, we describe an assay to study 3D T cell dynamics under flow in real time using a high-throughput, artificial membrane-free microfluidic platform that allows unimpeded extravasation of T cells. We show that primary human T cells adhere to endothelial vessel walls upon perfusion of microvessels and can be stimulated to undergo transendothelial migration (TEM) by TNFα-mediated vascular inflammation and the presence of CXCL12 gradients or ECM-embedded melanoma cells. Notably, migratory behavior was found to differ depending on T cell activation states. The assay is unique in its comprehensiveness for modelling T cell trafficking, arrest, extravasation and migration, all in one system, combined with its throughput, quality of imaging and ease of use. We envision routine use of this assay to study immunological processes and expect it to spur research in the fields of immunological disorders, immuno-oncology and the development of novel immunotherapeutics.

Background In cardiovascular diseases, atherosclerotic disorder are the most frequent and important with respect to morbidity and mortality. Inflammation mediated by immune cells is central in all parts of the atherosclerotic progress, and further understanding of the underlying mechanisms is needed. Growing evidence suggests that deamination of adenosine-to-inosine in RNA is crucial for a correct immune response; nevertheless, the role of adenosine-to-inosine RNA editing in atherogenesis has barely been studied. Several proteins have affinity for inosines in RNA, one being ENDOV (endonuclease V), which binds and cleaves RNA at inosines. Data on ENDOV in atherosclerosis are lacking. Methods and Results Quantitative polymerase chain reaction on ENDOV mRNA showed an increased level in human carotid atherosclerotic plaques compared with control veins. Inosine-ribonuclease activity as measured by an enzyme activity assay is detected in immune cells relevant for the atherosclerotic process. Abolishing EndoV in atherogenic apolipoprotein E-deficient ( ApoE -/- ) mice reduces the atherosclerotic plaque burden, both in size and lipid content. In addition, in a brain stroke model, mice without ENDOV suffer less damage than control mice. Finally, lack of EndoV reduces the recruitment of monocytes to atherosclerotic lesions in atherogenic ApoE -/- mice. Conclusions ENDOV is upregulated in human atherosclerotic lesions, and data from mice suggest that ENDOV promotes atherogenesis by enhancing the monocyte recruitment into the atherosclerotic lesion, potentially by increasing the effect of CCL2 activation on these cells.

Background: Due to the ban on classroom teaching during the pandemic, the Munich "Anamnesegruppen" had to be switched to e-learning at short notice. There were no established concepts for this, which is why digitalization was piloted and evaluated for feasibility. Student "Anamnesegruppen": "Anamnesegruppen" have existed for over 50 years and are organized as independent student peer teaching. In small groups of medical and psychology students, interviews with patients are conducted once a week during the semester. This is followed by a feedback and discussion round, in which ethical and professional questions are discussed in addition to the patient's medical history. The goal is to train the participants' ability to communicate and reflect. Adaptation to digital methods: The anamnesis seminars have been moved to a virtual group room using video conference. Patients were mainly recruited from the participants' circle of acquaintances. The group size was set at eight people each in four groups and supervised by a pair of student tutors. Confidentiality and data protection declarations were obtained in writing. Results: By switching to digital anamnesis groups, all four groups were successfully completed. Both the final supervision of the tutors and the electronic evaluation of the participants yielded positive feedback. Compared to the two previous evaluations of the semesters in classroom sessions, there were no significant differences in the evaluation. Discussion: The continuously good evaluation results, which did not differ between the digital format and the classroom course of the previous semesters, show that an ad hoc conversion to digital teaching is possible. We want to stress the fact that elements reflecting the doctor-patient relationship were successfully preserved. For the similarly structured Balint groups, virtual sessions may also be considered. Further research, especially prospective, is desirable in order to better understand the possibilities of digital teaching in this area., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2021 Kunisch et al.)

Endonuclease V (EndoV) is a conserved inosine-specific ribonuclease with unknown biological function. Here, we present the first mouse model lacking EndoV, which is viable without visible abnormalities. We show that endogenous murine EndoV cleaves inosine-containing RNA in vitro, nevertheless a series of experiments fails to link an in vivo function to processing of such transcripts. As inosine levels and adenosine-to-inosine editing often are dysregulated in hepatocellular carcinoma (HCC), we chemically induced HCC in mice. All mice developed liver cancer, however, EndoV-/- tumors were significantly fewer and smaller than wild type tumors. Opposed to human HCC, adenosine deaminase mRNA expression and site-specific editing were unaltered in our model. Loss of EndoV did not affect editing levels in liver tumors, however mRNA expression of a selection of cancer related genes were reduced. Inosines are also found in certain tRNAs and tRNAs are cleaved during stress to produce signaling entities. tRNA fragmentation was dysregulated in EndoV-/- livers and apparently, inosine-independent. We speculate that the inosine-ribonuclease activity of EndoV is disabled in vivo, but RNA binding allowed to promote stabilization of transcripts or recruitment of proteins to fine-tune gene expression. The EndoV-/- tumor suppressive phenotype calls for related studies in human HCC., (© The Author(s) 2020. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Endonuclease V (ENDOV) is a ribonuclease with affinity for inosine which is the deamination product of adenosine. The genomes of most organisms, including human, encode ENDOV homologs, yet knowledge about in vivo functions and gene regulation is sparse. To contribute in this field, we analyzed mRNA and protein expression of human ENDOV (hENDOV). Analyses of public sequence databases revealed numerous hENDOV transcript variants suggesting extensive alternative splicing. Many of the transcripts lacked one or more exons corresponding to conserved regions of the ENDOV core domain, suggesting that these transcripts do not encode for active proteins. Three complete transcripts were found with open reading frames encoding 282, 308 and 309 amino acids, respectively. Recombinant hENDOV 308 and hENDOV 309 share the same cleavage activity as hENDOV 282 which is the variant that has been used in previous studies of hENDOV. However, hENDOV 309 binds inosine-containing RNA with stronger affinity than the other isoforms. Overexpressed GFP-fused isoforms were found in cytoplasm, nucleoli and arsenite induced stress granules in human cells as previously reported for hENDOV 282. RT-qPCR analysis of the 3'-termini showed that hENDOV 308 and hENDOV 309 transcripts are more abundant than hENDOV 282 transcripts in immortalized cell lines, but not in primary cells, suggesting that cells regulate hENDOV mRNA expression. In spite of the presence of all three full-length transcripts, mass spectrometry analyses identified peptides corresponding to the hENDOV 309 isoform only. This result suggests that further studies of human ENDOV should rather encompass the hENDOV 309 isoform., Competing Interests: The authors have declared that no competing interests exist.

Microtubule targeting agents (MTAs) are used for the treatment of cancer. Novel MTAs could provide additional and beneficial therapeutic options. To improve the sensitivity and throughput of standard immunofluorescence assays for the characterization of MTAs, we used SNAP-tag technology to produce recombinant tubulin monomers. To visualize microtubule filaments, A549 cells transfected with SNAP-tubulin were stained with a membrane-permeable, SNAP-reactive dye. The treatment of SNAP-tubulin cells with stabilizing MTAs such as paclitaxel resulted in the formation of coarsely structured microtubule filaments, whereas depolymerizing MTAs such as nocodazole resulted in diffuse staining patterns in which the tubulin filaments were no longer distinguishable. By combining these components with automated microscopy and image analysis algorithms, we established a robust high-content screening assay for MTAs with a Z' factor of 0.7. Proof of principle was achieved by testing a panel of 10 substances, allowing us to identify MTAs and to distinguish between stabilizing and destabilizing modes of action. By extending the treatment of the cells from 2 to 20 h, our assay also detected abnormalities in cell cycle progression and in the formation of microtubule spindles, providing additional readouts for the discovery of new MTAs and facilitating their early identification during drug-screening campaigns.

Endonuclease V (EndoV) is an enzyme with specificity for inosines in nucleic acids. Whereas the bacterial homologs are active on both DNA and RNA, the mammalian variants only cleave RNA, at least when assayed with recombinant proteins. Here we show that ectopically expressed, as well as endogenously expressed human (h)EndoV, share the same enzymatic properties as the recombinant protein and cleaves RNA with inosine but not DNA. In search for proteins interacting with hEndoV, polyadenylate-binding protein C1 (PABPC1) was identified. The association between PABPC1 and hEndoV is RNA dependent and furthermore, PABPC1 stimulates hEndoV activity and affinity for inosine-containing RNA. Upon cellular stress, PABPC1 relocates to cytoplasmic stress granules that are multimolecular aggregates of stalled translation initiation complexes formed to aid cell recovery. Arsenite, as well as other agents, triggered relocalization also of hEndoV to cytoplasmic stress granules. As inosines in RNA are highly abundant, hEndoV activity is likely regulated in cells to avoid aberrant cleavage of inosine-containing transcripts. Indeed, we find that hEndoV cleavage is inhibited by normal intracellular ATP concentrations. The ATP stores inside a cell do not overlay stress granules and we suggest that hEndoV is redistributed to stress granules as a strategy to create a local environment low in ATP to permit hEndoV activity., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Triple-negative breast cancer (TNBC) is a heterogeneous disease in which the tumors do not express estrogen receptor (ER), progesterone receptor (PgR) or human epidermal growth factor receptor 2 (HER2). Classical receptor-targeted therapies such as tamoxifen or trastuzumab are therefore unsuitable and combinations of surgery, chemotherapy and/or radiotherapy are required. Photoimmunotheranostics is a minimally invasive approach in which antibodies deliver nontoxic photosensitizers that emit light to facilitate diagnosis and produce cytotoxic reactive oxygen species to induce apoptosis and/or necrosis in cancer cells. We developed a panel of photoimmunotheranostic agents against three TNBC-associated cell surface antigens. Antibodies against epidermal growth factor receptor (EGFR), epithelial cell adhesion molecule (EpCAM) and chondroitin sulfate proteoglycan 4 (CSPG4) were conjugated to the highly potent near-infrared imaging agent/photosensitizer IRDye®700DX phthalocyanine using SNAP-tag technology achieving clear imaging in both breast cancer cell lines and human biopsies and highly potent phototherapeutic activity with IC50values of 62-165 nM against five different cell lines expressing different levels of EGFR, EpCAM and CSPG4. A combination of all three reagents increased the therapeutic activity against TNBC cells by up to 40%.

Purpose: Rhabdomyosarcoma (RMS) is a rare and aggressive soft tissue sarcoma with limited treatment options and a high failure rate during standard therapy. New therapeutic strategies based on targeted immunotherapy are therefore much in demand. The epidermal growth factor receptor (EGFR) has all the characteristics of an ideal target. It is overexpressed in up to 80 % of embryonal RMS and up to 50 % of alveolar RMS tumors. We therefore tested the activity of the EGFR-specific recombinant immunotoxin (IT) 425(scFv)-ETA' against EGFR(+) RMS cells in vitro and ex vivo., Methods: We tested the specific binding and internalization behavior of 425(scFv)-ETA' in RMS cell lines in vitro by flow cytometry, compared to the corresponding imaging probe 425(scFv)-SNAP monitored by live cell imaging. The cytotoxic activity of 425(scFv)-ETA' was tested using cell viability and apoptosis assays. Specific binding of the IT was confirmed on formalin-fixed paraffin-embedded tissue samples from two RMS patients., Results: We confirmed the specific binding of 425(scFv)-ETA' to RMS cells in vitro and ex vivo. Both the IT and the corresponding imaging probe were rapidly internalized. The IT killed EGFR(+) RMS cells in a dose-dependent manner, while showing no effect against control cells. It showed specific apoptotic activity against one selected RMS cell line., Conclusions: This is the first study showing the promising therapeutic potential of a recombinant, EGFR-targeting, ETA'-based IT on RMS cells. We confirmed the selective killing with IC50 values of up to 50 pM, and immunohistochemical staining confirmed the specific ex vivo binding to primary RMS material.

In normal epithelia, the epithelial cell adhesion molecule (EpCAM) expression is relatively low and only present at the basolateral cell surface. In contrast, EpCAM is aberrantly overexpressed in various human carcinomas. Therefore, EpCAM is considered to be a highly promising target for antibody-based cancer immunotherapy. Here, we present a new and fully human cytolytic fusion protein (CFP), designated "anti-EpCAM(scFv)-MAP," that is comprised of an EpCAM-specific antibody fragment (scFv) genetically fused to the microtubule-associated protein tau (MAP). Anti-EpCAM(scFv)-MAP shows potent EpCAM-restricted proapoptotic activity toward rapidly proliferating carcinoma cells. In vitro assays confirmed that treatment with anti-EpCAM(scFv)-MAP resulted in the colocalization and stabilization of microtubules, suggesting that this could be the potential mode of action. Dose-finding experiments indicated that anti-EpCAM(scFv)-MAP is well tolerated in mice. Using noninvasive far-red in vivo imaging in a tumor xenograft mouse model, we further demonstrated that anti-EpCAM(scFv)-MAP inhibited tumor growth in vivo. In conclusion, our data suggest that anti-EpCAM(scFv)-MAP may be of therapeutic value for the targeted elimination of EpCAM(+) carcinomas., (©2014 American Association for Cancer Research.)