Local light-activation of the Src oncoprotein in an epithelial monolayer promotes collective extrusion

International audienceTransformed isolated cells are usually extruded from normal epithelia and subsequently eliminated. However, multicellular tumors outcompete healthy cells, highlighting the importance of collective effects. Here, we investigate this situation in vitro by controlling in space and time the activity of the Src oncoprotein within a normal Madin-Darby Canine Kidney (MDCK) epithelial cell monolayer. Using an optogenetics approach with cells expressing a synthetic light-sensitive version of Src (optoSrc), we reversibly trigger the oncogenic activity by exposing monolayers to well-defined light patterns. We show that small populations of activated optoSrc cells embedded in the non-transformed monolayer collectively extrude as a tridimensional aggregate and remain alive, while the surrounding normal cells migrate towards the exposed area. This phenomenon requires an interface between normal and transformed cells and is partially reversible. Traction forces show that Src-activated cells either actively extrude or are pushed out by the surrounding cells in a non-autonomous way

Dictionnaire des relations internationales : approches, concepts, doctrines

553 p.2e éditio

Yield of FDG PET/CT for Defining the Extent of Disease in Patients with Kaposi Sarcoma

International audienceBackground: Positron emission tomography/computed tomography with fluorodeoxyglucose (F-18) (FDG PET/CT) is increasingly used in Kaposi sarcoma (KS), but its value has not been assessed. Objectives: In this study, we aimed to evaluate the diagnostic accuracy of FDG PET/CT to define the extent of disease in KS. Methods: Consecutive patients with KS referred to our department for FDG PET/CT were included. The diagnostic accuracy of FDG PET/CT for cutaneous and extra-cutaneous KS staging was assessed on a per lesion basis compared to staging obtained from clinical examination, standard imaging, endoscopy, histological analyses, and follow-up. Results: From 2007 to 2017, 75 patients with FDG PET/CT were analyzed. The sensitivity and specificity of FDG PET/CT for the overall detection of KS lesions were 71 and 98%, respectively. Sensitivity and specificity were 100 and 85% for lymph nodes, 87 and 98% for bone, 87 and 100% for lungs, and 100 and 100% for muscle involvement, whereas sensitivity was only 17% to detect KS digestive involvement. The sensitivity of the diagnostic for KS cutaneous involvement increased from 73 to 88% when using a whole-body examination. Conclusion: FDG PET/CT showed good sensitivity and specificity for KS staging (digestive involvement excepted) and could be used for staging patients with active KS

Idarucizumab (Praxbind ® ) for dabigatran reversal in patients undergoing heart transplantation: a cohort of ten patients

International audienceBackground: Novel oral anticoagulants are used in atrial fibrillation. Idarucizumab has been approved for reversal of dabigatran in situations of life-threatening hemorrhage or emergency surgery.Objectives: We report a single center experience of ten patients on dabigatran therapy who were given idarucizumab prior to heart transplantation. Methods & results: The mean plasma concentration of dabigatran prior to reversal was 139 ± 89 ng/ml. Hemoglobin, hematocrit and platelet levels were decreased after surgery. Surgical procedures were successfully performed with no increased risk, especially regarding bleeding complications. All patients were alive after 90 days.Conclusion: Dabigatran reversal with idarucizumab in contexts of emergency surgery/urgent procedures is an attractive and safe option to be taken into consideration for patients with end stage heart disease awaiting transplantation and indication of anticoagulant therapy

Multimarker approach including CRP, sST2 and GDF‐15 for prognostic stratification in stable heart failure

International audienceAims Inflammation and cardiac remodelling are common and synergistic pathways in heart failure (HF). Emerging biomarkers such as soluble suppression of tumorigenicity 2 (sST2) and growth differentiation factor-15 (GDF-15), which are linked to inflammation and fibrosis process, have been proposed as prognosis factors. However, their potential additive values remain poorly investigated. Methods and results Here, we aimed at evaluating inflammatory and remodelling biomarkers to predict both short-term and long-term mortality in a population with chronic HF in comparison with other classical clinical or biological markers (i.e. N terminal pro brain natriuretic peptide, hs-cTnT, C-reactive protein) alone or using meta-analysis global group in chronic HF risk score in a cohort of 182 patients followed during 80 months (interquartile range: 12.3-90.0). Proportional hazard assumption does not hold for sST2 and C-reactive protein, and follow-up was split into short term (less than 1 year), midterm (between 1 and 5 years), and long term (after 5 years). In univariate analysis, C-reactive protein and sST2 were predictive of short-term mortality but not of middle term and long term whereas GDF-15 was predictive of short and mid-term but not of long-term mortality. In a multivariate model after adjustment for meta-analysis global group in chronic HF score including the three markers, only sST2 was predictive of short-term mortality (P = 0.0225), and only GDF-15 was predictive of middle term mortality (P = 0.0375). None of the markers was predictive of long-term mortality. Conclusions Our results demonstrate that both sST2 and GDF-15 significantly improve the prognosis evaluation of HF patients and suggest that the value of GDF-15 is more sustained overtime and could predict middle term events

Heart graft preservation technics and limits: an update and perspectives

Heart transplantation, the gold standard treatment for end-stage heart failure, is limited by heart graft shortage, justifying expansion of the donor pool. Currently, static cold storage (SCS) of hearts from donations after brainstem death remains the standard practice, but it is usually limited to 240 min. Prolonged cold ischemia and ischemia-reperfusion injury (IRI) have been recognized as major causes of post-transplant graft failure. Continuous ex situ perfusion is a new approach for donor organ management to expand the donor pool and/or increase the utilization rate. Continuous ex situ machine perfusion (MP) can satisfy the metabolic needs of the myocardium, minimizing irreversible ischemic cell damage and cell death. Several hypothermic or normothermic MP methods have been developed and studied, particularly in the preclinical setting, but whether MP is superior to SCS remains controversial. Other approaches seem to be interesting for extending the pool of heart graft donors, such as blocking the paths of apoptosis and necrosis, extracellular vesicle therapy, or donor heart-specific gene therapy. In this systematic review, we summarize the mechanisms involved in IRI during heart transplantation and existing targeting therapies. We also critically evaluate all available data on continuous ex situ perfusion devices for adult donor hearts, highlighting its therapeutic potential and current limitations and shortcomings