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International audience; Blood vessel-on-a-chip models aim at reproducing vascular functions. However, very few efficient methods have been designed to address the need for biological replicates in medium- to high-throughput screenings. Here, vessels-on-chip were designed in polydimethylsiloxane-glass chips using the viscous finger patterning technique which was adapted to create channels with various internal diameters inside a collagen solution and to simultaneously seed cells. This method was refined to create blood vessels composed of two concentric, distinct, and closely appositioned layers of human endothelial and perivascular cells arranged around a hollow lumen. These approaches allowed the formation of structurally correct blood vessels-on-chips which were constituted of either only endothelial cells or of both cell types in order to distinguish the vascular barrier reactivity to drugs in the presence or not of perivascular cells. The established vessels showed a tight vascular barrier, as assessed by immunostaining of the adherens junctions, and were reactive to the natural vasopermeant thrombin and to inflammatory cytokines. The presence of perivascular cells markedly increased the tightness of the vascular barrier and lowered its response to thrombin. The design allowed us to simultaneously challenge in real-time several tens of 3D-reconstituted, multicellular blood vessels in a standard multiwell plate format suitable for high-throughput drug screening.

Compelling evidence points to the MET receptor tyrosine kinase as a key player during liver development and regeneration. Recently, a role of MET in the pathophysiology of insulin resistance and obesity is emerging. Herein, we aimed to determine whether MET regulates hepatic insulin sensitivity. To achieve this, mice in which the expression of wild-type MET in hepatocytes is slightly enhanced above endogenous levels (Alb-R26Met mice) were analyzed to document glucose homeostasis, energy balance, and insulin signaling in hepatocytes. We found that Alb-R26Met mice exhibited higher body weight and food intake when compared to R26stopMet control mice. Metabolic analyses revealed that Alb-R26Met mice presented age-related glucose and pyruvate intolerance in comparison to R26stopMet controls. Additionally, in Alb-R26Met mice, high MET levels decreased insulin-induced insulin receptor (IR) and AKT phosphorylation compared to control mice. These results were corroborated in vitro by analyzing IR and AKT phosphorylation in primary mouse hepatocytes from Alb-R26Met and R26stopMet mice upon insulin stimulation. Moreover, co-immunoprecipitation assays revealed MET-IR interaction under both basal and insulin stimulation conditions; this effect was enhanced in Alb-R26Met hepatocytes. Altogether, our results indicate that enhanced MET levels alter hepatic glucose homeostasis, which can be an early event for subsequent liver pathologies., This work was supported by the Spanish Ministry of Science and Innovation with the help of European FEDER funding (RTI2018-094052-B-100), Comunidad de Madrid, Spain (S2017/BMD3684), and Fundación Ramón Areces and CIBERDEM (ISCIII) to Á.M.V. P.R. was a recipient of an International Mobility Grant from CIBERDEM (ISCIII). C.S. was supported by a FRM fellowship. F.M. is supported by research funding from Institut National du Cancer, ITMO Cancer Aviesan and INCa within the framework of the 2021–2030 Cancer Control Strategy on funds administered by Inserm, Canceropôle Provence Alpes Côte d’Azur, Institute for Cancer and Immunology (Aix-Marseille University), GEFLUC—Les Entreprises contre le Cancer, FdF (Fondation de France), ARC (Association pour la Recherche sur le Cancer), and SATT Sud-Est. The contribution of the Region Provence-AlpesCôte d’Azur and of the Aix-Marseille Univ to the IBDM animal facility is acknowledged.

International audience; Simple SummaryFew studies have investigated the link between SARS-CoV-2 and health restrictions and its effects on the health of lung cancer (LC) patients. This study aimed to assess the impact of SARS-CoV-2 on activity volume, postoperative complications and in-hospital mortality (IHM) for LC resections in 2020 at the national level in France. Our study shows a decrease in the volume of LC resections, especially during the first lockdown. We also show that only 0.43% of patients hospitalized for LC surgery during 2020 developed a SARS-CoV-2 infection, but this low rate is counterbalanced by a high IHM (21%) in these 51 patients. Our findings suggest that, even if the IHM is high, LC surgery is feasible during a pandemic provided that the general guidance protocols edited by the surgical societies are respected. Therefore, this study provides further arguments to encourage teams to test for COVID-19 prior to surgery and patients to be vaccinated.AbstractFew studies have investigated the link between SARS-CoV-2 and health restrictions and its effects on the health of lung cancer (LC) patients. The aim of this study was to assess the impact of the SARS-CoV-2 epidemic on surgical activity volume, postoperative complications and in-hospital mortality (IHM) for LC resections in France. All data for adult patients who underwent pulmonary resection for LC in France in 2020, collected from the national administrative database, were compared to 2018–2019. The effect of SARS-CoV-2 on the risk of IHM and severe complications within 30 days among LC surgery patients was examined using a logistic regression analysis adjusted for age, sex, comorbidities and type of resection. There was a slight decrease in the volume of LC resections in 2020 (n = 11,634), as compared to 2018 (n = 12,153) and 2019 (n = 12,227), with a noticeable decrease in April 2020 (the peak of the first wave of epidemic in France). We found that SARS-CoV-2 (0.43% of 2020 resections) was associated with IHM and severe complications, with, respectively, a sevenfold (aOR = 7.17 (3.30–15.55)) and almost a fivefold (aOR = 4.76 (2.31–9.80)) increase in risk. Our study suggests that LC surgery is feasible even during a pandemic, provided that general guidance protocols edited by the surgical societies are respected

International audience; Some miRNAs are located in RNA precursors (pri-miRNAs) annotated as long non-coding (lncRNAs) due to absence of long open reading frames (ORFs). However, recent studies have shown that some lnc pri-miRNAs encode peptides called miPEPs (miRNA-encoded peptides). Initially discovered in plants, three miPEPs have also been identified in humans. Herein, we found that a dozen human pri-miRNAs potentially encode miPEPs, as revealed by ribosome profiling and proteomic databases survey. So far, the only known function of plant miPEPs is to enhance the transcription of their own pri-miRNAs, thereby increasing the level and activity of their associated miRNAs and downregulating the expression of their target genes. To date, in humans, only miPEP133 was shown to promote a positive autoregulatory loop. We investigated whether other human miPEPs are also involved in regulating the expression of their miRNAs by studying miPEP155, encoded by the lnc MIR155HG, miPEP497, a sORF-encoded peptide within lnc MIR497HG, and miPEP200a, encoded by the pri-miRNA of miR-200a/miR-200b. We show that overexpression of these miPEPs is unable to impact the expression/activity of their own pri-miRNA/miRNAs in humans, indicating that the positive feedback regulation observed with plant miPEPs and human miPEP133 is not a general rule of human miPEP function.

Paclitaxel is a microtubule stabilizing agent and a successful drug for cancer chemotherapy inducing, however, adverse effects. To reduce the effective dose of paclitaxel, we searched for pharmaceutics which could potentiate its therapeutic effect. We screened a chemical library and selected Carba1, a carbazole, which exerts synergistic cytotoxic effects on tumor cells grown in vitro, when co-administrated with a low dose of paclitaxel. Carba1 targets the colchicine binding-site of tubulin and is a microtubule-destabilizing agent. Catastrophe induction by Carba1 promotes paclitaxel binding to microtubule ends, providing a mechanistic explanation of the observed synergy. The synergistic effect of Carba1 with paclitaxel on tumor cell viability was also observed in vivo in xenografted mice. Thus, a new mechanism favoring paclitaxel binding to dynamic microtubules can be transposed to in vivo mouse cancer treatments, paving the way for new therapeutic strategies combining low doses of microtubule targeting agents with opposite mechanisms of action., This work was supported by INSERM, Université Grenoble Alpes, CNRS, and by l’Institut National du Cancer (INCa, PLBIO16186), Fondation ARC (PJA 20151203348) and Association “Le Cancer du Sein, Parlons-en!”, to L.L., by Grant Ministerio de Economia y Competitividad grant BFU2016-75319-R, (AEI/FEDER, UE), European Union H2020-MSCA-ITN-ETN/0582 ITN TubInTrain to FDP, and The Netherlands Organization for Scientific Research (NWO) CW ECHO grant (711.015.005) to Anna Akhmanova The Optimal imaging platform is supported by France Life Imaging (French program “Investissement d’Avenir” grant; “Infrastructure d’avenir en Biologie Santé”, ANR-11-INBS-0006) and the IBISA French consortium “Infrastructures en Biologie Santé et Agronomie”.