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La maladie de Sjögren (Sjo) est une épithélite auto-immune ciblant notamment les cellules épithéliales salivaires (CES). Les CES jouent un rôle dans la xérostomie et dans le maintien de l'inflammation. Ainsi, l'étude des CES et de leur interaction avec les cellules immunitaires est fondamentale pour la compréhension de la maladie. Les modèles de souris ne reproduisant pas parfaitement les maladies humaines, notre objectif était de développer un modèle ex vivo d'organoïdes de glandes salivaires (OGS) de patients Sjo. Les biopsies de glandes salivaires accessoires (BGSA) de patients Sjo et de contrôles avec syndrome sec ont été dissociés puis encapsulés dans une matrice extracellulaire (Matrigel®) et cultivés en expansion (EXP) dans un milieu spécifique pour la culture à long terme. Les OGS étaient ensuite différenciés (DIF) dans un milieu spécifique, d'abord en Matrigel® puis en plaque 96 puits à faible adhérence. Les OGS ont été caractérisés par microscopie optique, histologie, RT-qPCR et RNA sequencing. Les « swelling assays » ont été capturés par vidéomicroscopie (Incucyte SX5). Nous avons inclus 13 Sjo et 15 contrôles. L'expansion à long terme était comparable dans les deux groupes, avec une durée moyenne de culture de 3,3 ± 1,7 mois. Les OGS se différentiaient dans les deux groupes, formant des structures d'allures acinaires et ductales, et acquérant des marqueurs épithéliaux acinaires – AQP5, amylase, Mist1 (p < 0,05) – et ductaux – CK5, CK7 (p < 0,05) (Figure 1A-B). On observait toutefois une morphologie altérée des organoïdes différenciés chez les Sjo, avec moins de formation de structure canalaires ramifiées. Nous avons alors analysé le profil transcriptomique des OGS de Sjo et retrouvé un enrichissement des voies de signalisation en rapport avec les interférons (IFN) de type I et II, témoignant une signature IFN persistante chez les patients Sjo malgré la culture prolongée en l'absence de stimulation IFN (Figure 1C). Nous avons ensuite évalué la fonction des OGS. Exposés à des stimuli inflammatoires par le Poly(I :C) et l'IFNα, les OGS étaient capables de produire des cytokines pro-inflammatoires, telles que BAFF, CXCL10 et IL-7. Nous avons ensuite évalué la fonction sécrétoire des OGS en les exposant à un agoniste cholinergique, la pilocarpine (« swelling assay »). Les OGS répondaient à la stimulation en grossissant, témoignant d'une réponse salivaire. Les OGS de Sjo répondaient significativement moins bien à la pilocarpine que les contrôles à 25 μM (p < 0,001) et 50 μM (p < 0,01) (Figure 1D). Du fait de la signature IFN des OGS de Sjo, nous avons évalué l'impact d'une inhibition de JAK/STAT par le tofacitinib (anti-JAK1/3) sur la réponse cholinergique, comme preuve de concept. Nous avons observé une amélioration de la réponse cholinergique chez les patients Sjo (p < 0,05) après 24 h d'exposition, témoignant d'une possible réversibilité de cette altération par le ciblage de la voie JAK/STAT (Figure 1E). Nous avons établi un modèle ex vivo de culture à long terme OGS de Sjo à partir de BGSA de petites tailles prélevées chez des patients à visée diagnostique, avec différentiation organotypique et fonctionnalité du tissu initial. Les OGS de Sjo reproduisaient le phénotype de la maladie, avec une morphologie altérée, une signature IFN persistante et une fonction altérée. La prochaine étape consistera à intégrer les cellules immunitaires au système pour mieux modéliser la maladie. Ce modèle permettra de mieux comprendre la maladie et d'évaluer l'effet de nouvelles thérapeutiques sur la fonction salivaire. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality globally, with significant public health concerns. This review examines the landscape of KRAS inhibition in colorectal cancer (CRC), focusing on recent advances in therapeutic strategies targeting this oncogene. Historically deemed undruggable due to its complex structure and essential role in tumorigenesis, KRAS mutations are prevalent in CRC and are associated with poor prognosis. However, breakthroughs in drug development have led to the emergence of KRAS inhibitors as promising treatment options. This review discusses various classes of KRAS inhibitors, including covalent and non-covalent inhibitors, as well as combination therapies aimed at enhancing efficacy and overcoming resistance mechanisms. It highlights recent clinical trials evaluating the efficacy of KRAS inhibitors either as monotherapy or in combination with other agents, such as anti-EGFR antibodies. Despite challenges such as resistance mechanisms and tumor heterogeneity, the development of KRAS inhibitors represents a significant advance in CRC treatment and holds promise for improving patient outcomes in the future.

Background & Aims: Patient-derived organoids (PDOs) are promising tumor avatars that could enable ex vivo drug tests to personalize patients' treatments in the frame of functional precision oncology. However, clinical evidence remains scarce. This study aims to evaluate whether PDOs can be implemented in clinical practice to benefit patients with advanced refractory pancreatic ductal adenocarcinoma (PDAC)., Methods: During 2021 to 2022, 87 patients were prospectively enrolled in an institutional review board-approved protocol. Inclusion criteria were histologically confirmed PDAC with the tumor site accessible. A panel of 25 approved antitumor therapies (chemogram) was tested and compared to patient responses to assess PDO predictive values and map the drug sensitivity landscape in PDAC., Results: Fifty-four PDOs were generated from 87 pretreated patients (take-on rate, 62%). The main PDO mutations were KRAS (96%), TP53 (88%), and CDKN2A/B (22%), with a 91% concordance rate with their tumor of origin. The mean turnaround time to chemogram was 6.8 weeks. In 91% of cases, ≥1 hit was identified (gemcitabine (n = 20 of 54), docetaxel (n = 18 of 54), and vinorelbine (n = 17 of 54), with a median of 3 hits/patient (range, 0-12). Our cohort included 34 evaluable patients with full clinical follow-up. We report a chemogram sensitivity of 83.3% and specificity of 92.9%. The overall response rate and progression-free survival were higher when patients received a hit treatment as compared to patients who received a nonhit drug (as part of routine management). Finally, we leveraged our PDO collection as a platform for drug validation and combo identification. We tested anti-KRAS G12D (MRTX1133), alone or combined, and identified a specific synergy with anti-EGFR therapies in KRAS G12D variants., Conclusions: We report the largest prospective study aiming at implementing PDO-based functional precision oncology and identify very robust predictive values in this clinical setting. In a clinically relevant turnaround time, we identify putative hits for 91% of patients, providing unexpected potential survival benefits in this very aggressive indication. Although this remains to be confirmed in interventional precision oncology trials, PDO collection already provides powerful opportunities for drugs and combinatorial treatment development., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Colorectal cancer (CRC) is the second cause of cancer-related death; the CpG-island methylation pathway (CIMP) is associated with KRAS/BRAF mutations, two oncogenes rewiring cell metabolism, worse prognosis, and resistance to classical chemotherapies. Despite this, the question of a possible metabolic rewiring in CIMPs has never been investigated. Here, we analyse whether metabolic dysregulations are associated with tumour methylation by evaluating the transcriptome of CRC tumours. CIMP-high patients were found to present a hypermetabolism, activating mainly carbohydrates, folates, sphingolipids, and arachidonic acid metabolic pathways. A third of these genes had epigenetic targets of Myc in their proximal promoter, activating carboxylic acid, tetrahydrofolate interconversion, nucleobase, and oxoacid metabolisms. In the Myc signature, the expression of GAPDH, TYMS, DHFR, and TK1 was enough to predict methylation levels, microsatellite instability (MSI), and mutations in the mismatch repair (MMR) machinery, which are strong indicators of responsiveness to immunotherapies. Finally, we discovered that CIMP tumours harboured an increase in genes involved in the one-carbon metabolism, a pathway critical to providing nucleotides for cancer growth and methyl donors for DNA methylation, which is associated with worse prognosis and tumour hypermethylation. Transcriptomics could hence become a tool to help clinicians stratify their patients better.

Apicobasal epithelial polarity controls the functional properties of most organs. Thus, there has been extensive research on the molecular intricacies governing the establishment and maintenance of cell polarity. Whereas loss of apicobasal polarity is a well-documented phenomenon associated with multiple diseases, less is known regarding another type of apicobasal polarity alteration - the inversion of polarity. In this Review, we provide a unifying definition of inverted polarity and discuss multiple scenarios in mammalian systems and human health and disease in which apical and basolateral membrane domains are interchanged. This includes mammalian embryo implantation, monogenic diseases and dissemination of cancer cell clusters. For each example, the functional consequences of polarity inversion are assessed, revealing shared outcomes, including modifications in immune surveillance, altered drug sensitivity and changes in adhesions to neighboring cells. Finally, we highlight the molecular alterations associated with inverted apicobasal polarity and provide a molecular framework to connect these changes with the core cell polarity machinery and to explain roles of polarity inversion in health and disease. Based on the current state of the field, failure to respond to extracellular matrix (ECM) cues, increased cellular contractility and membrane trafficking defects are likely to account for most cases of inverted apicobasal polarity., Competing Interests: Competing interests F.J. is the CEO of a Gustave Roussy spin-off (Orakl)., (© 2024. Published by The Company of Biologists Ltd.)

Background: KRAS mutation is the most common molecular alteration in pancreatic adenocarcinoma (PDAC), and around 10% of patients harbor KRAS wild-type tumors (KRAS WT )., Methods: A retrospective chart review of clinical/molecular data was performed including all PDAC patients with a determined KRAS status (tumor molecular profiling on tissue or liquid biopsy)., Results: 342 patients were included with 54 KRAS WT PDAC (16%) compared to 288 patients with KRAS m PDAC. Median age was 61 years [IQR:54.0;67.0] and 164 pts (48%) were female. At diagnosis, KRAS WT patients (63%) were more frequently diagnosed at a non-metastatic stage compared to KRAS m patients (41%) (p = 0.003). Regarding metastatic sites, liver was less frequent in KRAS WT (39%, p < 0.0001). Median overall survival (mOS) from initial diagnosis was significantly higher in the KRAS WT group compared to KRAS m (50.8 months, CI95% [32.0-NR] vs 21.1 months, CI95% [18.9-23.4] (p < 0.004 after adjustment on age, ECOG and stage at diagnosis). In first-line systemic treatment, (mostly FOLFIRINOX) progression-free survival (PFS) was also higher in KRAS WT . Based on ESCAT classification, a putative actionable alteration (ESCAT I-III) was identified in 19 (36%) KRAS WT pts and 46 (16%) KRAS m patients (p < 0.0001) with more alterations in FGFR2, BRAF(V600E), NRTK and more MSI tumors. KRAS WT harbored also fewer alterations in TP53, CDKN2A, and SMAD4. 12 KRAS WT patients received a molecularly-matched treatment with clinical benefit and improved outcomes compared to KRAS m patients., Conclusions: KRAS WT patients display distinct disease characteristics and outcomes with prolonged overall survival. KRAS WT patients also harbor more actionable molecular alterations, leading to higher survival rates after receiving molecularly matched treatments., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Antoine Hollebecque: Amgen, AstraZeneca, Debiopharm, Eli Lilly and Company, Incyte Corporation, QED Therapeutics. David Malka: Roche, Amgen, Bayer, Sanofi, Merck Serono, Servier, Sanofi, Pierre Fabre, Viatris, Bristol Myers Squibb, MSD Oncology, LEO Pharma, Incyte, AstraZeneca, Taiho Oncology, Pfizer. Fanny Jaulin: ORAKL. Valérie Boige: Amgen, AstraZeneca, Bayer Schering Pharma, Ipsen, Merck Serono, MSD Oncology, Roche/Genentech. Michel Ducreux: Merck Serono, MSD, AMGEN, Roche, Bayer, Ipsen, Pfizer, Servier, Pierre Fabre, HalioDx, Lilly, Sanofi, BMS. Alice Boilève: Merck Serono, Ipsen. Other authors report no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Patient Derived Organoids (PDOs) emerged as the best technology to develop ex vivo tumor avatars. Whether drug testing on PDOs to identify efficient therapies will bring clinical utility by improving patient survival remains unclear. To test this hypothesis in the frame of clinical trials, PDO technology faces three main challenges to be implemented in routine clinical practices: i) generating PDOs with a limited amount of tumor material; ii) testing a wide panel of anti-cancer drugs; and iii) obtaining results within a time frame compatible with patient disease management. We aimed to address these challenges in a prospective study in patients with colorectal cancer (CRC)., Methods: Fresh surgical or core needle biopsies were obtained from patients with CRC. PDOs were established and challenged with a panel of 25 FDA-approved anti-cancer drugs (chemotherapies and targeted therapies) to establish a scoring method ('chemogram') identifying in vitro responders. The results were analyzed at the scale of the cohort and individual patients when the follow-up data were available., Results: A total of 25 PDOs were successfully established, harboring 94% concordance with the genomic profile of the tumor they were derived from. The take-on rate for PDOs derived from core needle biopsies was 61.5%. A chemogram was obtained with a 6-week median turnaround time (range, 4-10 weeks). At least one hit (mean 6.16) was identified for 92% of the PDOs. The number of hits was inversely correlated to disease metastatic dissemination and the number of lines of treatment the patient received. The chemograms were compared to clinical data obtained from 8 patients and proved to be predictive of their response with 75% sensitivity and specificity., Conclusions: We show that PDO-based drug tests can be achieved in the frame of routine clinical practice. The chemogram could provide clinicians with a decision-making tool to tailor patient treatment. Thus, PDO-based functional precision oncology should now be tested in interventional trials assessing its clinical utility for patients who do not harbor activable genomic alterations or have developed resistance to standard of care treatments., (© 2023. Italian National Cancer Institute ‘Regina Elena’.)

Cancers rely on multiple, heterogeneous processes at different scales, pertaining to many biomedical fields. Therefore, understanding cancer is necessarily an interdisciplinary task that requires placing specialised experimental and clinical research into a broader conceptual, theoretical, and methodological framework. Without such a framework, oncology will collect piecemeal results, with scant dialogue between the different scientific communities studying cancer. We argue that one important way forward in service of a more successful dialogue is through greater integration of applied sciences (experimental and clinical) with conceptual and theoretical approaches, informed by philosophical methods. By way of illustration, we explore six central themes: (i) the role of mutations in cancer; (ii) the clonal evolution of cancer cells; (iii) the relationship between cancer and multicellularity; (iv) the tumour microenvironment; (v) the immune system; and (vi) stem cells. In each case, we examine open questions in the scientific literature through a philosophical methodology and show the benefit of such a synergy for the scientific and medical understanding of cancer., (© 2023 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

Long duration spaceflights to the Moon or Mars are at risk for emergency medical events. Managing a hypoxemic distress and performing an advanced airway procedure such as oro-tracheal intubation may be complicated under weightlessness due to ergonomic constraints. An emergency free-floating intubation would be dangerous because of high failure rates due to stabilization issues that prohibits its implementation in a space environment. Nevertheless, we hypothesized that two configurations could lead to a high first-pass success score for intubation performed by a free-floating operator. In a non-randomized, controlled, cross-over simulation study during a parabolic flight campaign, we evaluated and compared the intubation performance of free-floating trained operators, using either a conventional direct laryngoscope in an ice-pick position or an indirect laryngoscopy with a video-laryngoscope in a classic position at the head of a high-fidelity simulation manikin, in weightlessness and in normogravity. Neither of the two tested conditions reached the minimal terrestrial ILCOR recommendations (95% first-pass success) and therefore could not be recommended for general implementation under weightlessness conditions. Free-floating video laryngoscopy at the head of the manikin had a significant better success score than conventional direct laryngoscopy in an ice-pick position. Our results, combined with the preexisting literature, emphasis the difficulties of performing oro-tracheal intubation, even for experts using modern airway devices, under postural instability in weightlessness. ClinicalTrials registration number NCT05303948., (© 2023. Springer Nature Limited.)

Background: Despite improvements in characterization of CRC heterogeneity, appropriate risk stratification tools are still lacking in clinical practice. This study aimed to elucidate the primary tumor transcriptomic signatures associated with distinct metastatic routes., Methods: Primary tumor specimens obtained from CRC patients with either isolated LM (CRC-Liver) or PM (CRC-Peritoneum) were analyzed by transcriptomic mRNA sequencing, gene set enrichment analyses (GSEA) and immunohistochemistry. We further assessed the clinico-pathological associations and prognostic value of our signature in the COAD-TCGA independent cohort., Results: We identified a significantly different distribution of Consensus Molecular Subtypes between CRC-Liver and CRC-peritoneum groups. A transcriptomic signature based on 61 genes discriminated between liver and peritoneal metastatic routes. GSEA showed a higher expression of immune response and epithelial invasion pathways in CRC-Peritoneum samples and activation of proliferation and metabolic pathways in CRC-Liver samples. The biological relevance of RNA-Seq results was validated by the immunohistochemical expression of three significantly differentially expressed genes ( ACE2, CLDN18 and DUSP4 ) in our signature. In silico analysis of the COAD-TCGA showed that the CRC-Peritoneum signature was associated with negative prognostic factors and poor overall and disease-free survivals., Conclusions: CRC primary tumors spreading to the liver and peritoneum display significantly different transcriptomic profiles. The implementation of this signature in clinical practice could contribute to identify new therapeutic targets for stage IV CRC and to define individualized follow-up programs in stage II-III CRC.

The recent health crisis has increased the workload and the stress levels of healthcare professionals around the world. Such stressful working environments are conducive to an increased incidence of medical errors. Implementing education and training specifically focused on human and organizational factors can promote teamwork and decrease the risk of error. Such techniques have been extensively deployed, most notably in commercial aviation. Numerous tools have been developed to reduce the risk of error associated with routine tasks, forgetting a task and handling alarm situations during commercial flights. Many of these tools can be transferred to the healthcare sector. After a brief recap about the importance of the working environment, this narrative review aims to highlight several specific tools used in commercial aviation that can be readily transferred to the operating theatre., (©Copyright 2023 by the Turkish Anesthesiology and Reanimation Association / Turkish Journal of Anaesthesiology & Reanimation is published by Galenos Publishing House.)

Objective: To provide guidelines to define the place of human factors in the management of critical situations in anaesthesia and critical care., Design: A committee of nineteen experts from the SFAR and GFHS learned societies was set up. A policy of declaration of links of interest was applied and respected throughout the guideline-producing process. Likewise, the committee did not benefit from any funding from a company marketing a health product (drug or medical device). The committee followed the GRADE® method (Grading of Recommendations Assessment, Development and Evaluation) to assess the quality of the evidence on which the recommendations were based., Methods: We aimed to formulate recommendations according to the GRADE® methodology for four different fields: 1/ communication, 2/ organisation, 3/ working environment and 4/ training. Each question was formulated according to the PICO format (Patients, Intervention, Comparison, Outcome). The literature review and recommendations were formulated according to the GRADE® methodology., Results: The experts' synthesis work and application of the GRADE® method resulted in 21 recommendations. Since the GRADE® method could not be applied in its entirety to all the questions, the guidelines used the SFAR "Recommendations for Professional Practice" A means of secured communication (RPP) format and the recommendations were formulated as expert opinions., Conclusion: Based on strong agreement between experts, we were able to produce 21 recommendations to guide human factors in critical situations., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Cell migration is essential to living organisms and deregulated in cancer. Single cell's migration ranges from traction-dependent mesenchymal motility to contractility-driven propulsive amoeboid locomotion, but collective cell migration has only been described as a focal adhesion-dependent and traction-dependent process. Here, we show that cancer cell clusters, from patients and cell lines, migrate without focal adhesions when confined into nonadhesive microfabricated channels. Clusters coordinate and behave like giant super cells, mobilizing their actomyosin contractility at the rear to power their migration. This polarized cortex does not sustain persistent retrograde flows, of cells or actin, like in the other modes of migration but rather harnesses fluctuating cell deformations, or jiggling. Theoretical physical modeling shows this is sufficient to create a gradient of friction forces and trigger directed cluster motion. This collective amoeboid mode of migration could foster metastatic spread by enabling cells to cross a wide spectrum of environments.

The metastatic progression of cancer remains a major issue in patient treatment. However, the molecular and cellular mechanisms underlying this process remain unclear. Here, we use primary explants and organoids from patients harboring mucinous colorectal carcinoma (MUC CRC), a poor-prognosis histological form of digestive cancer, to study the architecture, invasive behavior and chemoresistance of tumor cell intermediates. We report that these tumors maintain a robust apico-basolateral polarity as they spread in the peritumoral stroma or organotypic collagen-I gels. We identified two distinct topologies - MUC CRCs either display a conventional 'apical-in' polarity or, more frequently, harbor an inverted 'apical-out' topology. Transcriptomic analyses combined with interference experiments on organoids showed that TGFβ and focal adhesion signaling pathways are the main drivers of polarity orientation. Finally, we show that the apical-out topology is associated with increased resistance to chemotherapeutic treatments in organoids and decreased patient survival in the clinic. Thus, studies on patient-derived organoids have the potential to bridge histological, cellular and molecular analyses to decrypt onco-morphogenic programs and stratify cancer patients. This article has an associated First Person interview with the first author of the paper., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)

Gut dysbiosis has been associated with intestinal and extraintestinal malignancies, but whether and how carcinogenesis drives compositional shifts of the microbiome to its own benefit remains an open conundrum. Here, we show that malignant processes can cause ileal mucosa atrophy, with villous microvascular constriction associated with dominance of sympathetic over cholinergic signaling. The rapid onset of tumorigenesis induced a burst of REG3γ release by ileal cells, and transient epithelial barrier permeability that culminated in overt and long-lasting dysbiosis dominated by Gram-positive Clostridium species. Pharmacologic blockade of β-adrenergic receptors or genetic deficiency in Adrb2 gene, vancomycin, or cohousing of tumor bearers with tumor-free littermates prevented cancer-induced ileopathy, eventually slowing tumor growth kinetics. Patients with cancer harbor distinct hallmarks of this stress ileopathy dominated by Clostridium species. Hence, stress ileopathy is a corollary disease of extraintestinal malignancies requiring specific therapies., Significance: Whether gut dysbiosis promotes tumorigenesis and how it controls tumor progression remain open questions. We show that 50% of transplantable extraintestinal malignancies triggered a β-adrenergic receptor-dependent ileal mucosa atrophy, associated with increased gut permeability, sustained Clostridium spp.-related dysbiosis, and cancer growth. Vancomycin or propranolol prevented cancer-associated stress ileopathy. This article is highlighted in the In This Issue feature, p. 873., (©2021 American Association for Cancer Research.)

Background: Miscommunication is a leading cause of preventable incidents in healthcare. A number of checklists have been created in an attempt to improve patient outcomes with only a small impact. However, the 2009 WHO Surgical Safety Checklist demonstrated benefits in terms of reduced morbidity and mortality. Our aim was to determine whether use of a Postanaesthesia Team Handover (PATH) checklist would reduce hypoxaemic events in the postanaesthesia care unit (PACU)., Methods: This single-centre, prospective, pre-/post-implementation study was conducted between February 2019 and July 2020 in the PACU of Versailles Private Hospital, Paris, France. Pre-PATH implementation data were collected for 294 consecutive adult patients (≥18 yr old) admitted to the PACU and post-PATH implementation data were collected for 293 consecutive patients. The primary outcome was the rate of hypoxaemic events post-surgery during PACU stay., Results: The rates of hypoxaemic events were 4.1% (11/267 [95% confidence interval {CI}: 2.3-7.2%]) before the PATH checklist was introduced and 0.8% (2/266 [95% CI: 0.2-2.7%]) after. Patients in the PATH group were 5.6 times (odds ratio [OR] [95% CI: 1.3-33.6], P=0.041) less likely to have a hypoxaemic event than those in the control group. The handover process in the PATH checklist group also had significantly less interruptions (38.6% control vs 20.7% PATH; OR=2.5 [95% CI: 1.7-3.7]; P<0.0001)., Conclusions: Implementation of the PATH checklist in adult patients post-surgery was associated with a reduction in the rate of hypoxaemic events in the PACU. These findings support standardisation of the handover process with checklists following anaesthesia and surgery., Clinical Trial Registration: NCT03972423., (Copyright © 2021 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.)

Background: Mental health and well-being is a significant problem for medical students in training. In this study, we aim to estimate the prevalence of anxiety and depressive symptoms, burnout and psychosocial distress in French anaesthesia and intensive care residents., Methods: A national online observational study used validated questionnaires (Hospital Anxiety and Depression Scale (HADS), Copenhagen Burnout Inventory (CBI), Perceived Stress Scale (PSS) and work-related questions (work-hours per week, night shift per month, safety rest after night shift, average time to start and end work, break time and time for lunch) to assess mental health and well-being of French residents in anaesthesia and intensive care., Results: We obtained 519 answers (22.5% of 2302 students), 55% of respondents working in anaesthesia, 41% in intensive care at the time of study. Residents describe certain symptomatology in anxiety (19.8%) and depressive symptoms (7.8%). PSS identifies a perceived high stress (score > 27) for 55.7% of the subjects. The CBI questionnaire identifies 205 (38.9%) residents undergoing burnout, 80.7% working more than 48 h per week and 39.1% more than 60 h. The duration of work per week (> 50 h), gender (female) and on-going training in intensive care are independent risk factors of psychological suffering. Lifestyle and level of training are not statistically identified risk factors., Conclusion: This first online survey of French anaesthesia and intensive care residents reveals a significant frequency of anxiety and depressive symptoms, burnout and a link to potential targets of improvement in work conditions mainly related to the number of work hours per week., (Copyright © 2021 Société française d'anesthésie et de réanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.)

Competing Interests: The authors disclose no conflict of interest.

Chromosomal instability in cancer consists of dynamic changes to the number and structure of chromosomes 1,2 . The resulting diversity in somatic copy number alterations (SCNAs) may provide the variation necessary for tumour evolution 1,3,4 . Here we use multi-sample phasing and SCNA analysis of 1,421 samples from 394 tumours across 22 tumour types to show that continuous chromosomal instability results in pervasive SCNA heterogeneity. Parallel evolutionary events, which cause disruption in the same genes (such as BCL9, MCL1, ARNT (also known as HIF1B), TERT and MYC) within separate subclones, were present in 37% of tumours. Most recurrent losses probably occurred before whole-genome doubling, that was found as a clonal event in 49% of tumours. However, loss of heterozygosity at the human leukocyte antigen (HLA) locus and loss of chromosome 8p to a single haploid copy recurred at substantial subclonal frequencies, even in tumours with whole-genome doubling, indicating ongoing karyotype remodelling. Focal amplifications that affected chromosomes 1q21 (which encompasses BCL9, MCL1 and ARNT), 5p15.33 (TERT), 11q13.3 (CCND1), 19q12 (CCNE1) and 8q24.1 (MYC) were frequently subclonal yet appeared to be clonal within single samples. Analysis of an independent series of 1,024 metastatic samples revealed that 13 focal SCNAs were enriched in metastatic samples, including gains in chromosome 8q24.1 (encompassing MYC) in clear cell renal cell carcinoma and chromosome 11q13.3 (encompassing CCND1) in HER2 + breast cancer. Chromosomal instability may enable the continuous selection of SCNAs, which are established as ordered events that often occur in parallel, throughout tumour evolution.

Background: The risk of severe medical and surgical events during long-duration spaceflight is significant. In space, many environmental and psychological factors may make tracheal intubation more difficult than on Earth. We hypothesised that, in microgravity, tracheal intubation may be facilitated by the use of a videolaryngoscope compared with direct laryngoscopy., Methods: In a non-randomised, controlled, cross-over simulation study, we compared intubation performance of novice operators and experts, using either a direct laryngoscope or a videolaryngoscope, in weightlessness and in normogravity. The primary outcome was the success rate of tracheal intubation. Time to intubation and the confidence score into the success of tube placement were also recorded., Results: When novices attempted to intubate the trachea in microgravity, the success rate of tracheal intubation using a videolaryngoscope was significantly higher (20/25 [80%]; 95% confidence interval [CI], 64.3-95.7 vs eight/20 [40%]; 95% CI, 18.5-61.5; P=0.006), and intubation time was shorter, compared with using a direct laryngoscope. In normogravity, the success rate of tracheal intubation by experts was significantly higher than that by novices (16/20 [80%]; 95% CI, 62.5-97.5 vs seven/25 [28%]; 95% CI, 10.4-45.6; P=0.001), but in microgravity, there was no significant difference between the experts and novices (19/20 [95%]; 95% CI, 85.4-100 vs 20/25 [80%]; 95% CI, 64.3-95.7; P=0.113). Higher confidence scores were achieved with videolaryngoscopy compared with direct laryngoscopy by both experts and novices in both microgravity and normogravity., Conclusions: Videolaryngoscopy was associated with higher intubation success rate and speed, and higher confidence for correct tube placement by novice operators in microgravity, and as such may represent the best technique for advanced airway management during long-duration spaceflight., (Copyright © 2019 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.)

mTOR activation is essential and sufficient to cause polycystic kidneys in Tuberous Sclerosis Complex (TSC) and other genetic disorders. In disease models, a sharp increase of proliferation and cyst formation correlates with a dramatic loss of oriented cell division (OCD). We find that OCD distortion is intrinsically due to S6 kinase 1 (S6K1) activation. The concomitant loss of S6K1 in Tsc1-mutant mice restores OCD but does not decrease hyperproliferation, leading to non-cystic harmonious hyper growth of kidneys. Mass spectrometry-based phosphoproteomics for S6K1 substrates revealed Afadin, a known component of cell-cell junctions required to couple intercellular adhesions and cortical cues to spindle orientation. Afadin is directly phosphorylated by S6K1 and abnormally decorates the apical surface of Tsc1-mutant cells with E-cadherin and α-catenin. Our data reveal that S6K1 hyperactivity alters centrosome positioning in mitotic cells, affecting oriented cell division and promoting kidney cysts in conditions of mTOR hyperactivity.

Transendothelial migration (TEM) of leukocytes across the endothelium is critical for inflammation. In the endothelium, TEM requires the coordination of membrane movements and cytoskeletal interactions, including, prominently, recruitment of the lateral border recycling compartment (LBRC). The scaffold protein IQGAP1 was recently identified in a screen for LBRC-interacting proteins. Knockdown of endothelial IQGAP1 disrupted the directed movement of the LBRC and substantially reduced leukocyte TEM. Expression of truncated IQGAP1 constructs demonstrated that the calponin homology domain is required for IQGAP1 localization to endothelial borders and that the IQ domain, on the same IQGAP1 polypeptide, is required for its function in TEM. This is the first reported function of IQGAP1 requiring two domains to be present on the same polypeptide. Additionally, we show for the first time that IQGAP1 in the endothelium is required for efficient TEM in vivo. These findings reveal a novel function for IQGAP1 and demonstrate that IQGAP1 in endothelial cells facilitates TEM by directing the LBRC to the site of TEM., (© 2019 Sullivan et al.)

The metastatic progression of cancer is a multi-step process initiated by the local invasion of the peritumoral stroma. To identify the mechanisms underlying colorectal carcinoma (CRC) invasion, we collected live human primary cancer specimens at the time of surgery and monitored them ex vivo. This revealed that conventional adenocarcinomas undergo collective invasion while retaining their epithelial glandular architecture with an inward apical pole delineating a luminal cavity. To identify the underlying mechanisms, we used microscopy-based assays on 3D organotypic cultures of Caco-2 cysts as a model system. We performed two siRNA screens targeting Rho-GTPases effectors and guanine nucleotide exchange factors. These screens revealed that ROCK2 inhibition triggers the initial leader/follower polarization of the CRC cell cohorts and induces collective invasion. We further identified FARP2 as the Rac1 GEF necessary for CRC collective invasion. However, FARP2 activation is not sufficient to trigger leader cell formation and the concomitant inhibition of Myosin-II is required to induce invasion downstream of ROCK2 inhibition. Our results contrast with ROCK pro-invasive function in other cancers, stressing that the molecular mechanism of metastatic spread likely depends on tumour types and invasion mode., (© 2019 The Authors.)

Even though cell death modalities elicited by anticancer chemotherapy and radiotherapy have been extensively studied, the ability of anticancer treatments to induce non-cell-autonomous death has never been investigated. By means of multispectral imaging flow-cytometry-based technology, we analyzed the lethal fate of cancer cells that were treated with conventional anticancer agents and co-cultured with untreated cells, observing that anticancer agents can simultaneously trigger cell-autonomous and non-cell-autonomous death in treated and untreated cells. After ionizing radiation, oxaliplatin, or cisplatin treatment, fractions of treated cancer cell populations were eliminated through cell-autonomous death mechanisms, while other fractions of the treated cancer cells engulfed and killed neighboring cells through non-cell-autonomous processes, including cellular cannibalism. Under conditions of treatment with paclitaxel, non-cell-autonomous and cell-autonomous death were both detected in the treated cell population, while untreated neighboring cells exhibited features of apoptotic demise. The transcriptional activity of p53 tumor-suppressor protein contributed to the execution of cell-autonomous death, yet failed to affect the non-cell-autonomous death by cannibalism for the majority of tested anticancer agents, indicating that the induction of non-cell-autonomous death can occur under conditions in which cell-autonomous death was impaired. Altogether, these results reveal that chemotherapy and radiotherapy can induce both non-cell-autonomous and cell-autonomous death of cancer cells, highlighting the heterogeneity of cell death responses to anticancer treatments and the unsuspected potential contribution of non-cell-autonomous death to the global effects of anticancer treatment.

Metastases account for 90% of cancer-related deaths; thus, it is vital to understand the biology of tumour dissemination. Here, we collected and monitored >50 patient specimens ex vivo to investigate the cell biology of colorectal cancer (CRC) metastatic spread to the peritoneum. This reveals an unpredicted mode of dissemination. Large clusters of cancer epithelial cells displaying a robust outward apical pole, which we termed tumour spheres with inverted polarity (TSIPs), were observed throughout the process of dissemination. TSIPs form and propagate through the collective apical budding of hypermethylated CRCs downstream of canonical and non-canonical transforming growth factor-β signalling. TSIPs maintain their apical-out topology and use actomyosin contractility to collectively invade three-dimensional extracellular matrices. TSIPs invade paired patient peritoneum explants, initiate metastases in mice xenograft models and correlate with adverse patient prognosis. Thus, despite their epithelial architecture and inverted topology TSIPs seem to drive the metastatic spread of hypermethylated CRCs.

Estrogen-related receptor alpha (ERR1) is an orphan nuclear receptor that can bind transcriptional co-activators constitutively. ERR1 expression correlates with poor patient outcomes in breast cancer, heightening interest in this nuclear receptor as a therapeutic target. Because ERR1 has no known regulatory ligand, a major challenge in targeting its activity is to find cellular or synthetic modulators of its function. We identified an interaction between ERR1 and KIF17, a kinesin-2 family microtubule motor, in a yeast-2-hybrid screen. We confirmed the interaction using in vitro biochemical assays and determined that binding is mediated by the ERR1 ligand-binding/AF2 domain and the KIF17 C-terminal tail. Expression of KIF17 tail domain in either ER-negative or ER-positive breast cancer epithelial cells attenuated nuclear accumulation of newly synthesized ERR1 and inhibited ERR1 transcriptional activity. Conversely, ERR1 transcriptional activity was elevated significantly in KIF17 knock-out cells. Sequence analysis of the KIF17 tail domain revealed it contains a nuclear receptor box with a conserved LXXLL motif found in transcriptional co-activators. Expression of a 12 amino-acid peptide containing this motif was sufficient to inhibit ERR1 transcriptional activity and cell invasion, while deletion of this region from the KIF17 tail resulted in increased ERR1 activity. Together, these data suggest KIF17 modifies ERR1 function by two possible, non-exclusive mechanisms: (i) by regulating nuclear-cytoplasmic distribution or (ii) by competing with transcriptional co-activators for binding to ERR1. Thus targeting the ERR1-KIF17 interaction has potential as a novel strategy for treating breast cancer.

The kinesin KIF17 localizes at microtubule plus-ends where it contributes to regulation of microtubule stabilization and epithelial polarization. We now show that KIF17 localizes at cell-cell adhesions and that KIF17 depletion inhibits accumulation of actin at the apical pole of cells grown in 3D organotypic cultures and alters the distribution of actin and E-cadherin in cells cultured in 2D on solid supports. Overexpression of full-length KIF17 constructs or truncation mutants containing the N-terminal motor domain resulted in accumulation of newly incorporated GFP-actin into junctional actin foci, cleared E-cadherin from cytoplasmic vesicles and stabilized cell-cell adhesions to challenge with calcium depletion. Expression of these KIF17 constructs also increased cellular levels of active RhoA, whereas active RhoA was diminished in KIF17-depleted cells. Inhibition of RhoA or its effector ROCK, or expression of LIMK1 kinase-dead or activated cofilin(S3A) inhibited KIF17-induced junctional actin accumulation. Interestingly, KIF17 activity toward actin depends on the motor domain but is independent of microtubule binding. Together, these data show that KIF17 can modify RhoA-GTPase signaling to influence junctional actin and the stability of the apical junctional complex of epithelial cells., (© 2016. Published by The Company of Biologists Ltd.)

Epithelial polarization is associated with selective stabilization and reorganization of microtubule (MT) arrays. However, upstream events and downstream consequences of MT stabilization during epithelial morphogenesis are still unclear. We show that the anterograde kinesin KIF17 localizes to MT plus ends, stabilizes MTs, and affects epithelial architecture. Targeting of KIF17 to plus ends of growing MTs requires kinesin motor activity and interaction with EB1. In turn, KIF17 participates in localizing adenomatous polyposis coli (APC) to the plus ends of a subset of MTs. We found that KIF17 affects MT dynamics, polymerization rates, and MT plus end stabilization to generate posttranslationally acetylated MTs. Depletion of KIF17 from cells growing in three-dimensional matrices results in aberrant epithelial cysts that fail to generate a single central lumen and to polarize apical markers. These findings implicate KIF17 in MT stabilization events that contribute to epithelial polarization and morphogenesis.

A key process during epithelial polarization involves establishment of polarized transport routes from the Golgi to distinct apical and basolateral membrane domains. To do this, the machinery involved in selective trafficking must be regulated during differentiation. Our previous studies showed that KIF5B selectively transports vesicles containing p75-neurotrophin receptors to the apical membrane of polarized, but not non-polarized MDCK cells. To identify the kinesin(s) responsible for p75 trafficking in non-polarized MDCK cells we expressed KIF-specific dominant-negative constructs and assayed for changes in post-Golgi transport of p75 by time-lapse fluorescence microscopy. Overexpression of the tail domains of kinesin-3 family members that contain a C-terminal pleckstrin homology (PH) domain, KIF1A or KIF1Bbeta, attenuated the rate of p75 exit from the Golgi in non-polarized MDCK cells but not in polarized cells. Analysis of p75 post-Golgi transport in cells expressing KIF1A or KIF1Bbeta with their PH domains deleted revealed that vesicle transport by these motors depends on the PH domains. Furthermore, purified KIF1A and KIF1Bbeta tails interact with p75 vesicles and these interactions require the PH domain. Knockdown of canine KIF1A also inhibited exit of p75 from the Golgi, and this was rescued by expression of human KIF1A. Together these data demonstrate that post-Golgi transport of p75 in non-polarized epithelial cells is mediated by kinesin-3 family motors in a PH-domain-dependent process.

Microtubule-based vesicular transport is well documented in epithelial cells, but the specific motors involved and their regulation during polarization are largely unknown. We demonstrate that KIF5B mediates post-Golgi transport of an apical protein in epithelial cells, but only after polarity has developed. Time-lapse imaging of EB1-GFP in polarized MDCK cells showed microtubule plus ends growing toward the apical membrane, implying that plus end-directed N-kinesins might be used to transport apical proteins. Indeed, time-lapse microscopy revealed that expression of a KIF5B dominant negative or microinjection of function-blocking KIF5 antibodies inhibited selectively post-Golgi transport of the apical marker, p75-GFP, after polarization of MDCK cells. Expression of other KIF dominant negatives did not alter p75-GFP trafficking. Immunoprecipitation experiments demonstrated an interaction between KIF5B and p75-GFP in polarized, but not in subconfluent, MDCK cells. Our results demonstrate that apical protein transport depends on selective microtubule motors and that epithelial cells switch kinesins for post-Golgi transport during acquisition of polarity.