Single-cell transcriptomics reveals shared immunosuppressive landscapes of mouse and human neuroblastoma

BACKGROUND High-risk neuroblastoma is a pediatric cancer with still a dismal prognosis, despite multimodal and intensive therapies. Tumor microenvironment represents a key component of the tumor ecosystem the complexity of which has to be accurately understood to define selective targeting opportunities, including immune-based therapies. METHODS We combined various approaches including single-cell transcriptomics to dissect the tumor microenvironment of both a transgenic mouse neuroblastoma model and a cohort of 10 biopsies from neuroblastoma patients, either at diagnosis or at relapse. Features of related cells were validated by multicolor flow cytometry and functional assays. RESULTS We show that the immune microenvironment of MYCN-driven mouse neuroblastoma is characterized by a low content of T cells, several phenotypes of macrophages and a population of cells expressing signatures of myeloid-derived suppressor cells (MDSCs) that are molecularly distinct from the various macrophage subsets. We document two cancer-associated fibroblasts (CAFs) subsets, one of which corresponding to CAF-S1, known to have immunosuppressive functions. Our data unravel a complex content in myeloid cells in patient tumors and further document a striking correspondence of the microenvironment populations between both mouse and human tumors. We show that mouse intratumor T cells exhibit increased expression of inhibitory receptors at the protein level. Consistently, T cells from patients are characterized by features of exhaustion, expressing inhibitory receptors and showing low expression of effector cytokines. We further functionally demonstrate that MDSCs isolated from mouse neuroblastoma have immunosuppressive properties, impairing the proliferation of T lymphocytes. CONCLUSIONS Our study demonstrates that neuroblastoma tumors have an immunocompromised microenvironment characterized by dysfunctional T cells and accumulation of immunosuppressive cells. Our work provides a new and precious data resource to better understand the neuroblastoma ecosystem and suggest novel therapeutic strategies, targeting both tumor cells and components of the microenvironment

Assessment of the apparent bending stiffness and damping of multilayer plates; modelling and experiment

© 2018 Elsevier Ltd In the context of aeronautics, automotive and construction applications, the design of light multilayer plates with optimized vibroacoustical damping and isolation performances remains a major industrial challenge and a hot topic of research. This paper focuses on the vibrational behavior of three-layered sandwich composite plates in a broad-band frequency range. Several aspects are studied through measurement techniques and analytical modelling of a steel/polymer/steel plate sandwich system. A contactless measurement of the velocity field of plates using a scanning laser vibrometer is performed, from which the equivalent single layer complex rigidity (apparent bending stiffness and apparent damping) in the mid/high frequency ranges is estimated. The results are combined with low/mid frequency estimations obtained with a high-resolution modal analysis method so that the frequency dependent equivalent Young's modulus and equivalent loss factor of the composite plate are identified for the whole [40 Hz-20 kHz] frequency band. The results are in very good agreement with an equivalent single layer analytical modelling based on wave propagation analysis (model of Guyader). The comparison with this model allows identifying the frequency dependent complex modulus of the polymer core layer through inverse resolution. Dynamical mechanical analysis measurements are also performed on the polymer layer alone and compared with the values obtained through the inverse method. Again, a good agreement between these two estimations over the broad-band frequency range demonstrates the validity of the approach.status: publishe

Probing the Local Conformation within π-Conjugated One-dimensional Supramolecular Stacks using Frequency Modulation Atomic Force Microscopy

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Bearing degradation indicator using characteristic frequencies applied on non-stationary vibration signals

International audienceThe well-known bearing characteristic frequencies (BPFO,BPFI,...etc.) reflect the complex kinematic of oper-ating bearings. Far from the idealised perfect rolling assumptions, the experimental frequencies deviate fromtheir theoretical values. The deterioration of the bearing health is likely to induce changes in the kinematics,materialising by a shift in the characteristic frequencies. However, non-stationary operating conditions are alsoknown to influence these frequencies. In this work, the effect of loading and angular acceleration is assessedto measure the feasibility of a bearing degradation indicator using characteristic frequencies for non-stationaryoperating machines. The method is applied to the monitoring of industrial wind turbines

On the Photo-Induced Charge-Carrier Generation within Monolayers of Self-Assembled Organic Donor-Acceptor Dyads

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Vasa nervorum angiogenesis in prostate cancer with perineural invasion.

International audienceBACKGROUND: Perineural invasion (PNI) is generally accepted as a major route of cancer dissemination in malignancies associated with highly enervated organs. However, the effect of cancer cells on vasa nervorum remains unknown. We studied this effect in locally advanced prostate cancer, a high-risk feature associated with approximately 20% of prostate cancer specific mortality.METHODS: We used immunohistochemistry for CD34, fibroblast growth factor-2 (FGF-2), FSHR, podoplanin, vascular endothelial growth factor (VEGF), and VEGFR-2 as well as histochemical methods to examine the vasa nervorum of nerves invaded by cancer cells in tissue samples from 85 patients.RESULTS: The percentage of the nerve area occupied by CD34-positive vasa nervorum endothelial cells in nerves with PNI was much higher than in nerves without PNI (7.3 ± 1.2 vs 1.9 ± 0.4; P < 0.001 and 5.8 ± 0.6 vs 1.23 ± 0.8; P < 0.001 in pT3a and pT3b prostate cancer specimens, respectively). In 19/85 of the patients the CD34-positive vasa nervorum microvessels have a thick basement membrane, similar to the vessels in diabetic microangiopathy. This subendothelial layer contains collagen fibers. Vasa nervorum endothelia and Schwann cells express FGF-2 (nuclear localization) and FSHR (plasma membrane and cytoplasmic staining). Prostate cancer cells invading nerves express VEGF, a critical cytokine in tumor angiogenesis. The vasa nervorum of prostatic nerves with PNI did not express detectable levels of VEGFR-2. No podoplanin-positive lymphatic vessels were seen in nerves.CONCLUSION: In locally advanced prostate cancer, PNI of cancer cells is associated with formation of new endoneurial capillaries and changes of vasa nervorum morphology

Biopathological Significance of PIWI–piRNA Pathway Deregulation in Invasive Breast Carcinomas

International audienceSimple SummaryThe PIWI-piRNA ribonucleoproteic complexes are pivotal regulators of genome integrity, differentiation and homeostasis and their dysregulation has recently been implicated in carcinogenesis. The aim of this study was to analyze the four PIWILs gene expression in invasive breast carcinomas (IBC) at RNA level using quantitative RT-PCR and protein level using immunohistochemistry. In normal breast tissue, PIWILs 2 and 4 were solely expressed, whereas an abnormal emergence of PIWIL1 and 3 was observed in respectively 30% and 6% of IBCs. Conversely, PIWIL2 was underexpressed in 48.3% and PIWIL4 downregulated in 43.3% of IBCs. Similar patterns of PIWIL deregulation were observed in a multitumoral panel, suggesting a generic mechanism in most cancers. PIWIL2 underexpression was significantly associated with DNA methylation and strong cytotoxic immune response. Characterization of the newly recognized PIWIL-piRNA pathway in IBCs opens interesting therapeutic perspectives using piRNAs, hypomethylating drugs, checkpoints immunotherapies and anti-PIWIL 1–3 antibodies.AbstractThe PIWI proteins emerging in the development of human cancers, edify PIWI-piRNA ribonucleoproteic complexes acting as pivotal regulators of genome integrity, differentiation and homeostasis. The aim of this study is to analyze the four PIWILs gene expression in invasive breast carcinomas (IBCs): at RNA level using quantitative RT-PCR (n = 526) and protein level using immunohistochemistry (n = 150). In normal breast tissue, PIWILs 2 and 4 were solely expressed, whereas an abnormal emergence of PIWIL1 and 3 was observed in respectively 30% and 6% of IBCs. Conversely, PIWIL2 was underexpressed in 48.3% and PIWIL4 downregulated in 43.3% of IBCs. Significant positive associations were observed between PIWIL4 underexpression, HR+ status and HR+ ERBB2+ molecular subtype and PIWIL2 underexpression, PR- status, ERBB2- status and molecular subtype. Similar patterns of PIWIL deregulation were observed in a multitumoral panel, suggesting a generic mechanism in most cancers. PIWIL2-4 underexpression was mainly regulated at epigenetic or post-transcriptional levels. PIWIL2 underexpression was significantly associated with DNA methylation and strong cytotoxic immune response. PIWIL2-4 were mainly associated with genes implicated in cell proliferation. As a result of this study, characterization of the PIWIL-piRNA pathway in IBCs opens interesting therapeutic perspectives using piRNAs, hypomethylating drugs, checkpoints immunotherapies and anti-PIWIL 1–3 antibodies

FDG-PET/CT-based prognostic survival model after surgery for head and neck cancer

Rationale: The aims of this multicenter study were to identify clinical and preoperative PET/CT parameters predicting Overall Survival (OS) and Distant Metastasis Free Survival(DMFS) from a cohort of Head and Neck Squamous Cell Carcinoma (HNSCC) patients treated with surgery, to generate a prognostic model of OS and DMFS and to validate this prognostic model with an independent cohort. Materials and Methods: A total of 382 consecutive HNSCC patients divided into training (n = 318) and validation cohorts (n = 64) were retrospectively included. The following PET/CT parameters were analyzed: clinical parameters, SUVmax, SUVMean, Metabolic Tumor Volume (MTV), Total Lesion Glycolysis (TLG) and distance parameters for the primary tumor and lymph nodes defined by two segmentation methods (relative SUVmax threshold and absolute SUV threshold). Cox analyses were performed for OS and DMFS in the training cohort. The c-index was used to identify highly prognostic parameters. These prognostic parameters were externally tested in the validation cohort. Results: In multivariable analysis, the significant parameters for OS were T stage and Nodal-MTV, achieving a c-index of 0.64 (p<0.001). For DMFS, the significant parameters were T stage, Nodal-MTV and maximal tumor-node distance, with a c-index of 0.76 (p<0.001). These combinations of parameters were externally validated, achieving c-indices of 0.63 (p<0.001) and 0.71 (p<0.001) for OS and DMFS, respectively. Conclusion: The Nodal MTV associated with maximal distance between the primary tumor and the lymph node was significantly correlated with the risk of DMFS. Moreover, this parameter in addition to clinical parameters was associated with higher risk of death. These prognostic factors may be used to tailor individualized treatment

FDG-PET/CT-based prognostic survival model after surgery for head and neck cancer

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