Publications by authors named "Nicolas Elie"

36 Publications

Shotgun lipidomics and mass spectrometry imaging unveil diversity and dynamics in lipid composition.

iScience 2021 Feb 29;24(2):102115. Epub 2021 Jan 29.

Univ Lyon, CNRS, Université Claude Bernard Lyon 1, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100 Villeurbanne, France.

Sentinel species are playing an indispensable role in monitoring environmental pollution in aquatic ecosystems. Many pollutants found in water prove to be endocrine disrupting chemicals that could cause disruptions in lipid homeostasis in aquatic species. A comprehensive profiling of the lipidome of these species is thus an essential step toward understanding the mechanism of toxicity induced by pollutants. Both the composition and spatial distribution of lipids in freshwater crustacean were extensively examined herein. The baseline lipidome of gammarids of different sex and reproductive stages was established by high throughput shotgun lipidomics. Spatial lipid mapping by high resolution mass spectrometry imaging led to the discovery of sulfate-based lipids in hepatopancreas and their accumulation in mature oocytes. A diverse and dynamic lipid composition in was uncovered, which deepens our understanding of the biochemical changes during development and which could serve as a reference for future ecotoxicological studies.
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http://dx.doi.org/10.1016/j.isci.2021.102115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7881238PMC
February 2021

A PSMA-targeted theranostic approach is unlikely to be efficient in serous ovarian cancers.

EJNMMI Res 2021 Feb 9;11(1):11. Epub 2021 Feb 9.

UNICAEN, INSERM 1086 ANTICIPE, Normandy University, Caen, France.

Purpose: Until now, results evaluating the expression of PSMA in ovarian cancer were sparse and contradictory. The aim was to reinvestigate the feasibility of a PSMA targeted theranostic approach in epithelial ovarian cancers with data from the tumour bank of a referring cancer centre.

Materials And Methods: The OvaRessources Biological Resources Center database was screened from January 2004 to December 2017 to seek patients referred for the initial management of a serous epithelial ovarian cancer and for whom peritoneal histological samples were available in the tumour bank. Immunodetection of PSMA was performed to assess its cellular and neovascular expression. Slides were controlled by a certified pathologist, recorded as tiled tiff images and processed to compute the proportion of DAB stained surface.

Results: Of the 51 patients identified by the database screening, 32 patients were included resulting in 57 samples (32 pre-chemotherapy and 25 post-chemotherapy histological samples). Nine patients were chemo-sensitive, 10 were partially chemo-sensitive and 13 were chemo-resistant/refractory. In the entire dataset, the expression of PSMA was quasi-inexistent: %DAB = 0.04 (± 0.12) %. There was no significant difference in the %DAB of sensitive, partially sensitive and resistant/refractory patients. There was also no significant difference in %DAB in tumours before and after chemotherapy in the 25 patients for whom both samples were available.

Conclusion: The present work demonstrates that PSMA expression is negligible and a fortiori non-sufficient to ensure its usefulness as a prognosticator or a target for a theranostic strategy in ovarian cancers.
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http://dx.doi.org/10.1186/s13550-021-00756-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7873152PMC
February 2021

Hormonal Receptor Immunochemistry Heterogeneity and F-FDG Metabolic Heterogeneity: Preliminary Results of Their Relationship and Prognostic Value in Luminal Non-Metastatic Breast Cancers.

Front Oncol 2020 12;10:599050. Epub 2021 Jan 12.

INSERM 1086 ANTICIPE, Normandy University, Caen, France.

Introduction: We aimed to investigate whether F-FDG PET metabolic heterogeneity reflects the heterogeneity of estrogen receptor (ER) and progesterone receptor (PR) expressions within luminal non-metastatic breast tumors and if it could help in identifying patients with worst event-free survival (EFS).

Materials And Methods: On 38 PET high-resolution breast bed positions, a single physician drew volumes of interest encompassing the breast tumors to extract SUV, histogram parameters and textural features. High-resolution immunochemistry (IHC) scans were analyzed to extract Haralick parameters and descriptors of the distribution shape. Correlation between IHC and PET parameters were explored using Spearman tests. Variables of interest to predict the EFS status at 8 years (EFS-8y) were sought by means of a random forest classification. EFS-8y analyses were then performed using univariable Kaplan-Meier analyses and Cox regression analysis. When appropriate, Mann-Whitney tests and Spearman correlations were used to explore the relationship between clinical data and tumoral PET heterogeneity variables.

Results: For ER expression, correlations were mainly observed with F-FDG histogram parameters, whereas for PR expression correlations were mainly observed with gray-level co-occurrence matrix (GLCM) parameters. The strongest correlations were observed between skewness_ and uniformity_ (ρ = -0.386, p = 0.017) and correlation_ and entropy_ (ρ = 0.540, p = 0.001), respectively. The median follow-up was 6.5 years and the 8y-EFS was 71.0%. Random forest classification found age, clinical stage, SUV, skewness_, kurtosis_, entropy_, and uniformity_ to be variables of importance to predict the 8y-EFS. Univariable Kaplan-Meier survival analyses showed that skewness_ was a predictor of 8y-EFS (66.7 ± 27.2 versus 19.1 ± 15.2, p = 0.018 with a cut-off value set to 0.163) whereas other IHC and PET parameters were not. On multivariable analysis including age, clinical stage and skewness_, none of the parameters were independent predictors. Indeed, skewness_ was significantly higher in youngest patients (ρ = -0.351, p = 0.031) and in clinical stage III tumors (p = 0.023).

Conclusion: A heterogeneous distribution of ER within the tumor in IHC appeared as an EFS-8y prognosticator in luminal non-metastatic breast cancers. Interestingly, it appeared to be correlated with PET histogram parameters which could therefore become potential non-invasive prognosticator tools, provided these results are confirmed by further larger and prospective studies.
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http://dx.doi.org/10.3389/fonc.2020.599050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7837029PMC
January 2021

Anemia Management in Rural Haitian Children: A Mixed Methods Study.

J Transcult Nurs 2021 Jan 22:1043659620986616. Epub 2021 Jan 22.

Université d'Etat d'Haiti, Port-au-Prince, Ouest, Haiti.

Introduction: We examined factors influencing anemia outcomes in rural children following implementation of a prevention program.

Method: Mixed methods study of children, parents, and clinicians utilized statistical modeling and content/ethnographic analysis. Retrospective chart abstraction evaluated treatments administered and measured hemoglobin in children aged 6 to 59 months ( = 161). Prospective interviews/questionnaires examined parent ( = 51) and clinician ( = 19) perceptions.

Results: Anemia prevalence decreased by 21.2%. Predictors of increased hemoglobin were clinic visit number and age at first visit. Once anemia improved, children were likely to remain improved ( = .65). Despite favorable program perceptions, stakeholders emphasized ecological barriers, including social disadvantage and local practices.

Discussion: Socioeconomic factors prevented guideline concordant behaviors. Persistent attention to intrapersonal, interpersonal, and community social determinants is a sine qua non for successfully managing the epidemic. The first step to provide culturally congruent care is to explicitly acknowledge that guideline-concordant behaviors are often complex.
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http://dx.doi.org/10.1177/1043659620986616DOI Listing
January 2021

Impact of T161, Y318 and S363 alanine mutations on regulation of the human delta-opioid receptor (hDOPr) induced by peptidic and alkaloid agonists.

Neuropharmacology 2020 11 22;179:108286. Epub 2020 Aug 22.

Laboratoire de Signalisation, électrophysiologie et Imagerie des Lésions D'ischémie-reperfusion Myocardique, Normandie Univ, UNICAEN, Caen, France. Electronic address:

Previously, we showed a differential regulation of the human delta-opioid receptor (hDOPr) by etorphine and [D-Pen, D-Pen] enkephalin (DPDPE). To understand the molecular basis of such differences, we introduced 3 alanine mutations at the residues T161. Y318 and S363. Both wild type (WT) and hDOPr mutants were expressed in HEK cells containing endogenous arrestins or CFP-tagged arrestin 3, then desensitization, internalization, recycling and phosphorylation were studied. In a context of endogenous arrestin expression, a major difference in DOPr desensitization was observed between agonists that was modified with the T161A mutation upon etorphine and with the S363A substitution upon DPDPE exposure. While both agonists induced a major receptor internalization, T161A and S363A impaired DOPr sequestration only for etorphine. However, similar level of S363 phosphorylation was measured between agonists. When CFP-tagged arrestin 3 was over-expressed, a similar profile of desensitization was measured for both agonists. In this context, all the 3 alanine mutations decreased etorphine-induced receptor desensitization. Using FRET, we showed similar interactions between WT hDOPr and arrestin 3 under DPDPE and etorphine stimulation which were delayed by both the Y318A and the S363A substitutions for etorphine. Finally, hDOPr recycling was qualitatively evaluated by microscopy and showed neither arrestin 3/hDOPr colocalization nor major impact of alanine mutations except for the S363A which impaired internalization and recycling for etorphine. The T161, Y318 and S363 residues of hDOPr could underlie the differential regulation promoted by DPDPE and etorphine.
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http://dx.doi.org/10.1016/j.neuropharm.2020.108286DOI Listing
November 2020

Multimodal Imaging Mass Spectrometry to Identify Markers of Pulmonary Arterial Hypertension in Human Lung Tissue Using MALDI-ToF, ToF-SIMS, and Hybrid SIMS.

Anal Chem 2020 09 17;92(17):12079-12087. Epub 2020 Aug 17.

Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198, Gif-sur-Yvette, France.

Pulmonary arterial hypertension (PAH) is a rare and deadly disease affecting roughly 15-60 people per million in Europe with a poorly understood pathology. There are currently no diagnostic tools for early detection nor does a curative treatment exist. The lipid composition of arteries in lung tissue samples from human PAH and control patients were investigated using matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) combined with time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging. Using random forests as an IMS data analysis technique, it was possible to identify the ion at / 885.6 as a marker of PAH in human lung tissue. The / 885.6 ion intensity was shown to be significantly higher around diseased arteries and was confirmed to be a diacylglycerophosphoinositol PI(C18:0/C20:4) via MS/MS using a novel hybrid SIMS instrument. The discovery of a potential biomarker opens up new research avenues which may finally lead to a better understanding of the PAH pathology and highlights the vital role IMS can play in modern biomedical research.
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http://dx.doi.org/10.1021/acs.analchem.0c02815DOI Listing
September 2020

A macroscopic and stereological imaging dataset of Pleuronectes platessa ovaries.

Sci Data 2020 05 29;7(1):165. Epub 2020 May 29.

Institut Français de Recherche pour l'Exploitation de la Mer, IFREMER, Laboratoire Ressources Halieutiques de Port-en-Bessin, 14520, Port-en-Bessin-Huppain, France.

The North Sea plaice, Pleuronectes platessa (Linnaeus, 1758), is a commonly studied commercial flatfish with poorly known ovarian histology. The following dataset is a collection of female plaice gonad images and their corresponding histological slides, collected during a complete season of the plaice's reproduction cycle. Stereology was used to determine the percentage of different structures found throughout the ovaries. Inter-agent calibrations were accomplished in order to harmonize the stereological readings, and were based on a comprehensive reading protocol and histological lexicon that were specifically written for the plaice's ovaries. The distribution and homogeneity of the different cell types found throughout the ovaries were also evaluated. This dataset can be used to automate the stereological reading process (through statistical learning methods for example) or to objectively determine the plaice's maturity phase, and link that information to either macroscopic measurements or through image analysis of the full ovaries.
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http://dx.doi.org/10.1038/s41597-020-0505-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7260370PMC
May 2020

Investigating Tunneling Nanotubes in Cancer Cells: Guidelines for Structural and Functional Studies through Cell Imaging.

Biomed Res Int 2020 13;2020:2701345. Epub 2020 Apr 13.

Normandie University, UNIROUEN, INSERM, PRIMACEN, F-76821 Mont-Saint-Aignan, France.

By allowing insured communication between cancer cells themselves and with the neighboring stromal cells, tunneling nanotubes (TNTs) are involved in the multistep process of cancer development from tumorigenesis to the treatment resistance. However, despite their critical role in the biology of cancer, the study of the TNTs has been announced challenging due to not only the absence of a specific biomarker but also the fragile and transitory nature of their structure and the fact that they are hovering freely above the substratum. Here, we proposed to review guidelines to follow for studying the structure and functionality of TNTs in tumoral neuroendocrine cells (PC12) and nontumorigenic human bronchial epithelial cells (HBEC-3, H28). In particular, we reported how crucial is it (i) to consider the culture conditions (culture surface, cell density), (ii) to visualize the formation of TNTs in living cells (mechanisms of formation, 3D representation), and (iii) to identify the cytoskeleton components and the associated elements (categories, origin, tip, and formation/transport) in the TNTs. We also focused on the input of high-resolution cell imaging approaches including Stimulated Emission Depletion (STED) nanoscopy, Transmitted and Scanning Electron Microscopies (TEM and SEM). In addition, we underlined the important role of the organelles in the mechanisms of TNT formation and transfer between the cancer cells. Finally, new biological models for the identification of the TNTs between cancer cells and stromal cells (liquid air interface, , ) and the clinical considerations will also be discussed.
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http://dx.doi.org/10.1155/2020/2701345DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7174938PMC
February 2021

Do nitrogen- and sulphur-remobilization-related parameters measured at the onset of the reproductive stage provide early indicators to adjust N and S fertilization in oilseed rape (Brassica napus L.) grown under N- and/or S-limiting supplies?

Planta 2019 Dec 25;250(6):2047-2062. Epub 2019 Sep 25.

NORMANDIE UNIV, UNICAEN, INRA, 950 EVA, 14000, Caen, France.

Main Conclusion: Specific combinations of physiological and molecular parameters associated with N and S remobilization measured at the onset of flowering were predictive of final crop performances in oilseed rape. Oilseed rape (Brassica napus L.) is a high nitrogen (N) and sulphur (S) demanding crop. Nitrogen- and S-remobilization processes allow N and S requirements to reproductive organs to be satisfied when natural uptake is reduced, thus ensuring high yield and seed quality. The quantification of physiological and molecular indicators of early N and S remobilization could be used as management tools to correct N and S fertilization. However, the major limit of this corrective strategy is to ensure the correlation between final performances-related variables and early measured parameters. In our study, four genotypes of winter oilseed rape (OSR) were grown until seed maturity under four nutritional modalities combining high and/or low N and S supplies. Plant final performances, i.e., seed production, N- and S-harvest indexes, seed N and S use efficiencies, and early parameters related to N- or S-remobilization processes, i.e., photosynthetic leaf area, N and S leaf concentrations, leaf soluble protein and leaf sulphate concentrations, and leaf RuBisCO abundance at flowering, were measured. We demonstrated that contrasting final performances existed according to the N and S supplies. An optimal N:S ratio supply could explain the treatment-specific crop performances, thus justifying N and S concurrent managements. Specific combinations of early measured plant parameters could be used to predict final performances irrespective of the nutritional supply and the genotype. This work demonstrates the potential of physiological and molecular indicators measured at flowering to reflect the functioning of N- and S-compound remobilization and to predict yield and quality penalties. However, because the predictive models are N and S independent, instant N and S leaf analyses are required to further adjust the adequate fertilization. This study is a proof of a concept which opens prospects regarding instant diagnostic tools in the context of N and S mineral fertilization management.
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http://dx.doi.org/10.1007/s00425-019-03284-2DOI Listing
December 2019

Generation of a Molecular Network from Electron Ionization Mass Spectrometry Data by Combining MZmine2 and MetGem Software.

Anal Chem 2019 09 27;91(18):11489-11492. Epub 2019 Aug 27.

Institut de Chimie des Substances Naturelles , CNRS UPR2301, Université Paris-Sud, Université Paris-Saclay, Avenue de la Terrasse , 91190 Gif-sur-Yvette , France.

Molecular networking (MN) allows one to organize tandem mass spectrometry (MS/MS) data by spectral similarities. Cosine-score used as a metric to calculate the distance between two spectra is based on peak lists containing fragments and neutral losses from MS/MS spectra. Until now, the workflow excluded the generation of the molecular network from electron ionization (EI) MS data as no selection of the putative parent ion is achieved when performing classical gas chromatography (GC)-EI-MS analysis. In order to fill this gap, new functionalities on MetGem 1.2.2 software ( https://github.com/metgem/metgem/releases ) have been implemented, and results from a large EI-MS database and GC-EI-MS analysis will be exemplified.
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http://dx.doi.org/10.1021/acs.analchem.9b02802DOI Listing
September 2019

Structural Identification of Antibacterial Lipids from Amazonian Palm Tree Endophytes through the Molecular Network Approach.

Int J Mol Sci 2019 Apr 24;20(8). Epub 2019 Apr 24.

CNRS-Institut de Chimie des Substances Naturelles, UPR2301, Université Paris-Saclay, 91198 Gif-sur-Yvette CEDEX, France.

A library of 197 endophytic fungi and bacteria isolated from the Amazonian palm tree was extracted and screened for antibacterial activity against methicillin-resistant (MRSA). Four out of five antibacterial ethyl acetate extracts were also cytotoxic for the MRC-5 cells line. Liquid chromatography coupled to tandem mass spectrometry (UPHLC-HRMS/MS) analyses combined with molecular networking data processing were carried out to allow the identification of depsipeptides and cyclopeptides responsible for the cytotoxicity in the dataset. Specific ion clusters from the active sp. extract were also highlighted using an MRSA activity filter. A chemical study of sp. was conducted leading to the structural characterization of eight fatty acid exhibiting antimicrobial activity against MRSA in the tens of µg/mL range.
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http://dx.doi.org/10.3390/ijms20082006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6514718PMC
April 2019

NDR2 kinase contributes to cell invasion and cytokinesis defects induced by the inactivation of RASSF1A tumor-suppressor gene in lung cancer cells.

J Exp Clin Cancer Res 2019 Apr 12;38(1):158. Epub 2019 Apr 12.

Normandie University, UNICAEN, CEA, CNRS, ISTCT/CERVOxy group, GIP CYCERON, Avenue H.Becquerel- 14074, F-14000, Caen, France.

Background: RASSF1A, a tumor suppressor gene, is frequently inactivated in lung cancer leading to a YAP-dependent epithelial-mesenchymal transition (EMT). Such effects are partly due to the inactivation of the anti-migratory RhoB GTPase via the inhibitory phosphorylation of GEF-H1, the GDP/GTP exchange factor for RhoB. However, the kinase responsible for RhoB/GEF-H1 inactivation in RASSF1A-depleted cells remained unknown.

Methods: NDR1/2 inactivation by siRNA or shRNA effects on epithelial-mesenchymal transition, invasion, xenograft formation and growth in SCID-/- Beige mice, apoptosis, proliferation, cytokinesis, YAP/TAZ activation were investigated upon RASSF1A loss in human bronchial epithelial cells (HBEC).

Results: We demonstrate here that depletion of the YAP-kinases NDR1/2 reverts migration and metastatic properties upon RASSF1A loss in HBEC. We show that NDR2 interacts directly with GEF-H1 (which contains the NDR phosphorylation consensus motif HXRXXS/T), leading to GEF-H1 phosphorylation. We further report that the RASSF1A/NDR2/GEF-H1/RhoB/YAP axis is involved in proper cytokinesis in human bronchial cells, since chromosome proper segregation are NDR-dependent upon RASSF1A or GEF-H1 loss in HBEC.

Conclusion: To summarize, our data support a model in which, upon RASSF1A silencing, NDR2 gets activated, phosphorylates and inactivates GEF-H1, leading to RhoB inactivation. This cascade induced by RASSF1A loss in bronchial cells is responsible for metastasis properties, YAP activation and cytokinesis defects.
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http://dx.doi.org/10.1186/s13046-019-1145-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6461807PMC
April 2019

Inhibition of store-operated channels by carboxyamidotriazole sensitizes ovarian carcinoma cells to anti-Bclx strategies through Mcl-1 down-regulation.

Oncotarget 2018 Sep 21;9(74):33896-33911. Epub 2018 Sep 21.

Normandie University, UNICAEN, INSERM U1086 ANTICIPE, Interdisciplinary Research Unit for Cancer Prevention and Treatment, BioTICLA Axis, Biology and Innovative Therapeutics for Ovarian Cancers, Caen, France.

The anti-apoptotic proteins Bcl-x and Mcl-1 have been identified to play a pivotal role in apoptosis resistance in ovarian cancer and constitute key targets for innovative therapeutic strategies. Although BH3-mimetics (i.e. ABT-737) potently inhibit Bcl-x activity, targeting Mcl-1 remains a hurdle to the success of these strategies. Calcium signaling is profoundly remodeled during carcinogenesis and was reported to activate the signaling pathway controlling Mcl-1 expression. In this context, we investigated the effect of carboxyamidotriazole (CAI), a calcium channel inhibitor used in clinical trials, on Mcl-1 expression. CAI had an anti-proliferative effect on ovarian carcinoma cell lines and strongly down-regulated Mcl-1 expression. It inhibited store-operated calcium entry (SOCE) and Mcl-1 translation through mTORC1 deactivation. Moreover, it sensitized ovarian carcinoma cells to anti-Bcl-x strategies as their combination elicited massive apoptosis. Its effect on mTORC1 and Mcl-1 was mimicked by the potent SOCE inhibitor, YM58483, which also triggered apoptosis when combined with ABT-737. As a whole, this study suggests that CAI sensitizes to anti-Bcl-x strategies its action on Mcl-1 translation and that modulation of SOCE could extend the therapeutic arsenal for treatment of ovarian carcinoma.
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http://dx.doi.org/10.18632/oncotarget.26084DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6188062PMC
September 2018

MetGem Software for the Generation of Molecular Networks Based on the t-SNE Algorithm.

Anal Chem 2018 12 14;90(23):13900-13908. Epub 2018 Nov 14.

Institut de Chimie des Substances Naturelles, CNRS UPR 2301, Université Paris-Sud, Université Paris-Saclay, Avenue de la Terrasse , 91198 Gif-sur-Yvette , France.

Molecular networking (MN) is becoming a standard bioinformatics tool in the metabolomic community. Its paradigm is based on the observation that compounds with a high degree of chemical similarity share comparable MS fragmentation pathways. To afford a clear separation between MS spectral clusters, only the most relevant similarity scores are selected using dedicated filtering steps requiring time-consuming parameter optimization. Depending on the filtering values selected, some scores are arbitrarily deleted and a part of the information is ignored. The problem of creating a reliable representation of MS spectra data sets can be solved using algorithms developed for dimensionality reduction and pattern recognition purposes, such as t-distributed stochastic neighbor embedding (t-SNE). This multivariate embedding method pays particular attention to local details by using nonlinear outputs to represent the entire data space. To overcome the limitations inherent to the GNPS workflow and the networking architecture, we developed MetGem. Our software allows the parallel investigation of two complementary representations of the raw data set, one based on a classic GNPS-style MN and another based on the t-SNE algorithm. The t-SNE graph preserves the interactions between related groups of spectra, while the MN output allows an unambiguous separation of clusters. Additionally, almost all parameters can be tuned in real time, and new networks can be generated within a few seconds for small data sets. With the development of this unified interface ( https://metgem.github.io ), we fulfilled the need for a dedicated, user-friendly, local software for MS comparison and spectral network generation.
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http://dx.doi.org/10.1021/acs.analchem.8b03099DOI Listing
December 2018

Morphological and molecular criteria allow the identification of putative germ stem cells in a lophotrochozoan, the Pacific oyster Crassostrea gigas.

Histochem Cell Biol 2019 May 15;151(5):419-433. Epub 2018 Oct 15.

Normandy University, Caen, France.

While our knowledge of bivalve gametogenesis recently progressed, data on early stages of gametogenesis remain to be developed, especially when dealing with germinal stem cells (GSC) and their niche in these organisms. Here, we wish to develop a strategy to identify putative GSC in Pacific oyster Crassostrea gigas based on morphological criteria combined with vasa marker expression. A histological quantitative approach, based on stereology, allowed us to identify two types of early germ cells in the germinal epithelium, one presenting round nuclei and the other irregular ones. Both early germ cell types present slightly condensed chromatin in nucleus, are vasa-positive and the Oyvlg (oyster vasa-like gene) expression in these cells is recorded throughout the whole gametogenesis process. The microenvironment of an early germ cell in oyster includes an associated somatic cell presenting an immunolabeling for BMP2/4 and a close myoid cell. In agreement with the GSC characteristics in other species, we postulate that putative germ stem cells in C. gigas correspond to the early germ cell type with irregular nucleus shape; those early germ cells with a round nucleus may consist in progenitors.
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http://dx.doi.org/10.1007/s00418-018-1740-3DOI Listing
May 2019

A role for RASSF1A in tunneling nanotube formation between cells through GEFH1/Rab11 pathway control.

Cell Commun Signal 2018 10 11;16(1):66. Epub 2018 Oct 11.

Normandie Univ, UNICAEN, CEA, CNRS, ISTCT/CERVOxy group, GIP CYCERON, F-14000, Caen, France.

Background: By allowing intercellular communication between cells, tunneling nanotubes (TNTs) could play critical role in cancer progression. If TNT formation is known to require cytoskeleton remodeling, key mechanism controlling their formation remains poorly understood.

Methods: The cells of human bronchial (HBEC-3, A549) or mesothelial (H2452, H28) lines are transfected with different siRNAs (inactive, anti-RASSF1A, anti-GEFH1 and / or anti-Rab11). At 48 h post-transfection, i) the number and length of the nanotubes per cell are quantified, ii) the organelles, previously labeled with specific tracers, exchanged via these structures are monitored in real time between cells cultured in 2D or 3D and in normoxia, hypoxia or in serum deprivation condition.

Results: We report that RASSF1A, a key-regulator of cytoskeleton encoded by a tumor-suppressor gene on 3p chromosome, is involved in TNTs formation in bronchial and pleural cells since controlling proper activity of RhoB guanine nucleotide exchange factor, GEF-H1. Indeed, the GEF-H1 inactivation induced by RASSF1A silencing, leads to Rab11 accumulation and subsequent exosome releasing, which in turn contribute to TNTs formation. Finally, we provide evidence involving TNT formation in bronchial carcinogenesis, by reporting that hypoxia or nutriment privation, two almost universal conditions in human cancers, fail to prevent TNTs induced by the oncogenic RASSF1A loss of expression.

Conclusions: This finding suggests for the first time that loss of RASSF1A expression could be a potential biomarker for TNTs formation, such TNTs facilitating intercellular communication favoring multistep progression of bronchial epithelial cells toward overt malignancy.
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http://dx.doi.org/10.1186/s12964-018-0276-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6180646PMC
October 2018

Radial distribution of wood extractives in European larch Larix decidua by TOF-SIMS imaging.

Phytochemistry 2018 Jun 10;150:31-39. Epub 2018 Mar 10.

Institut de Chimie des Substances Naturelles, CNRS UPR 2301, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France. Electronic address:

Wood extractives in the xylem of European larch Larix decidua were mapped by time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging, which allows the radial distribution of both mineral and lipophilic extractives in the xylem to be scrutinized with high spatial resolution for the first time. Results show that all the components are inhomogeneously distributed across the annual ring. Mineral nutrients including Na, K, Ca, and Cl ions exhibit no preferential localization between earlywood and latewood, whereas PO ion is exclusively present in the ray cells, indicating it may be related to acid phosphatase. Lipophilic extractives were found to be more abundant in the inner secondary xylem. Ion images with 400 nm spatial resolution reveal that fatty acids, triglycerides and phytosterols are co-localized principally in the earlywood within the first annual ring. Resin acids prove to be the main components in the resin canal of the secondary xylem and are distributed in the outer of it.
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http://dx.doi.org/10.1016/j.phytochem.2018.02.017DOI Listing
June 2018

Insights into the MALDI Process after Matrix Deposition by Sublimation Using 3D ToF-SIMS Imaging.

Anal Chem 2018 02 17;90(3):1907-1914. Epub 2018 Jan 17.

Institut de Chimie des Substances Naturelles, CNRS UPR 2301, Université Paris-Sud, Université Paris-Saclay , 91190 Gif-sur-Yvette, France.

Imaging mass spectrometry (IMS) has become a powerful tool to characterize the spatial distribution of biomolecules in thin tissue sections. In the case of matrix-assisted laser desorption ionization (MALDI) IMS, homogeneous matrix deposition is critical to produce high-quality ion images, and sublimation in particular has shown to be an excellent matrix deposition method for the imaging of lipids. Matrix deposition by sublimation is, however, a completely solvent-free system, which ought to prevent the mixing of matrix and analytes thought to be necessary for successful MALDI. Using 3D time-of-flight secondary ion imaging mass spectrometry, we have studied the matrix-tissue interface in 3D with high resolution to understand the MALDI process of lipids after matrix deposition by sublimation. There is a strong indication that diffusion is the process by which lipids migrate from the tissue to the matrix layer. We show that triacylglycerols and phospholipids have a delayed migratory trend as compared to diacylglycerols and monoacylglycerols, which is dependent on time and matrix thickness. Additional experiments show that a pure lipid's capacity to migrate into the matrix is dependent on its fluidity at room temperature. Furthermore, it is shown that cholesterol can only migrate in the presence of a (fluid) lipid and appears to fluidize lipids, which could explain its colocalization with the diacylglycerols and monoacylglycerols in the matrix.
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http://dx.doi.org/10.1021/acs.analchem.7b03993DOI Listing
February 2018

Skin Penetration Enhancement by Natural Oils for Dihydroquercetin Delivery.

Molecules 2017 Sep 12;22(9). Epub 2017 Sep 12.

Department of Clinical Pharmacy, Lithuanian University of Health Sciences, Sukilėlių pr. 13, Kaunas 50166, Lithuania.

Natural oils are commonly used in topical pharmaceutical formulations as emulsifiers, stabilizers or solubility enhancers. They are presented as safe and inert components, mainly used for formulation purposes. It is confirmed that natural oils can affect the skin penetration of various substances. Fatty acids are mainly responsible for this effect. Current understanding lacks reliable scientific data on penetration of natural oils into the skin and their skin penetration enhancement potential. In the current study, fatty acid content analysis was used to determine the principal fatty acids in soybean, olive, avocado, sea-buckthorn pulp, raspberry seed and coconut oils. Time of flight secondary ion mass spectrometry bioimaging was used to determine the distribution of these fatty acids in human skin ex vivo after application of the oils. Skin penetration enhancement ratios were determined for a perspective antioxidant compound dihydroquercetin. The results demonstrated skin penetration of fatty acids from all oils tested. Only soybean and olive oils significantly increased the skin distribution of dihydroquercetin and can be used as skin penetration enhancers. However, no correlation can be determined between the fatty acids' composition and skin penetration enhancement using currently available methodological approaches. This indicates that potential chemical penetration enhancement should be evaluated during formulation of topically applied products containing natural oils.
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http://dx.doi.org/10.3390/molecules22091536DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6151382PMC
September 2017

Dual Beam Depth Profiling and Imaging with Argon and Bismuth Clusters of Prenylated Stilbenes on Glandular Trichomes of Macaranga vedeliana.

Anal Chem 2017 09 22;89(17):9247-9252. Epub 2017 Aug 22.

Institut de Chimie des Substances Naturelles, CNRS UPR 2301, Univ. Paris-Sud, Université Paris-Saclay , Avenue de la Terrasse, 91198 Gif-sur-Yvette, France.

Using a time-of-flight secondary ion mass spectrometer equipped with an argon cluster ion for sputtering and a bismuth liquid metal ion source for analysis, both surfaces of leaves and fruits of Macaranga vedeliana, an endemic New Caledonian species, have been for the first time analyzed by a dual beam depth profiling. To prevent in-vacuum evaporation of the liquid content of the small glandular trichomes covering fruits and leaves surfaces and also to be able to analyze their liquid content while preventing any sublimation of the latter, the samples were kept frozen during the whole experiment using a nitrogen cooled sample holder. Thus, it was possible to demonstrate that vedelianin, an active metabolite of the family of prenylated stilbenes named schweinfurthins, is only located in these glandular trichomes.
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http://dx.doi.org/10.1021/acs.analchem.7b02020DOI Listing
September 2017

Fatty acids penetration into human skin ex vivo: A TOF-SIMS analysis approach.

Biointerphases 2017 03 2;12(1):011003. Epub 2017 Mar 2.

Department of Clinical Pharmacy, Lithuanian University of Health Sciences, Sukilėlių pr. 13, 50166 Kaunas, Lithuania.

Linoleic, oleic, palmitoleic, palmitic, and stearic fatty acids (FAs) are commonly used in dermatological formulations. They differ by their structure, presence in the skin, and mode of application in pharmaceuticals and cosmetics compounding. These FAs are also known as chemical penetration enhancers, but their mechanisms of penetration enhancement and effect on barrier characteristics of the skin require additional study. In this study, the authors conducted an ex vivo analysis of the distribution of lipid components in the epidermis and dermis of human skin after applying individual FAs. The goal was to elucidate possible mechanisms of penetration enhancement and FA effects on barrier characteristics of the skin. FA penetration studies were conducted ex vivo on human skin and time-of-flight secondary ion mass spectrometry (TOF-SIMS) bioimaging analysis was performed to visualize and analyze distribution of FAs in skin sections. The current study demonstrated that TOF-SIMS imaging was effective in visualizing the distribution of linoleic, oleic, palmitoleic, palmitic, and stearic acid in the human skin ex vivo after the skin penetration experiment of individual FAs. The integration of the obtained TOF-SIMS images allowed a semiquantitative comparison of the effects induced by individual FA applications on the human skin ex vivo. FAs showed varying abilities to penetrate the skin and disorder the FAs within the skin, based on their structures and physicochemical properties. Linoleic acid penetrated the skin and changed the distribution of all the analyzed FAs. Skin treatment with palmitoleic or oleic acid increased the amounts of singular FAs in the skin. Penetration of saturated FAs was low, but it increased the detected amounts of linoleic acid in both skin layers. The results indicate that application of FAs on the skin surface induce redistribution of native FAs not only in the stratum corneum layer of epidermis but also in the lipid content of full epidermis and dermis layers. The results indicate that topically applied pharmaceutical products should be evaluated for potential chemical penetration enhancement and lipid component redistribution effects during formulation.
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http://dx.doi.org/10.1116/1.4977941DOI Listing
March 2017

Hyperglycemia-Induced Hypovolemia Is Involved in Early Cardiac Magnetic Resonance Alterations in Streptozotocin-Induced Diabetic Mice: A Comparison with Furosemide-Induced Hypovolemia.

PLoS One 2016 22;11(2):e0149808. Epub 2016 Feb 22.

Nuclear Medicine department, Caen University Hospital, Caen, France.

Aims: The aim of the study was to assess the early features of diabetic cardiomyopathy using cardiac magnetic resonance within the first week after streptozotocin injection in mice. We focused on the relationship between left ventricular function and hypovolemia markers in diabetic animals compared to a hypovolemic rodent model.

Methods And Results: Swiss mice were randomized into control (group C), streptozotocin-induced diabetes (group D) and furosemide-induced hypovolemia (group F) groups. Cardiac magnetic resonance, non-invasive blood pressure, urine volume, plasma markers of dehydration and cardiac histology were assessed in all groups. Mean blood glucose was higher in diabetic animals than in groups C and F (30.5±5.8 compared to 10.4±2.1 and 11.1±2.8 mmol/L, respectively; p<0.01). Diuresis was increased in animals from group D and F compared to C (14650±11499 and 1533±540 compared to 192±111 μL/24 h; p<0.05). End diastolic and end systolic volumes were lower in group D than in group C at week 1 (1.52±0.36 vs. 1.93±0.35 and 0.54±0.22 vs. 0.75±0.18 mL/kg, p<0.05). These left ventricular volume values in group D were comparable to those observed in the acute hypovolemia model (group F). Increased dehydration plasma markers and an absence of obvious intrinsic myocardial damage (evaluated by cardiac magnetic resonance and histology) suggest that a hemodynamic mechanism underlies the very early drop in left ventricular volumes in group D and provides a potential link to hyperglycemic osmotic diuresis.

Conclusions: Researchers using cardiac magnetic resonance in hyperglycemic rodent models should be aware of this hemodynamic mechanism, which may partially explain modifications in cardiac parameters in addition to diabetic myocardial damage.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0149808PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4763166PMC
July 2016

Design, synthesis of novel pyranotriazolopyrimidines and evaluation of their anti-soybean lipoxygenase, anti-xanthine oxidase, and cytotoxic activities.

J Enzyme Inhib Med Chem 2016 Dec 18;31(6):1277-85. Epub 2015 Dec 18.

c Faculté De Pharmacie De Toulouse , Laboratoire Des Interactions Moléculaires Et Réactivité Chimique Et Photochimique UMR CNRS 5623, Université Paul-Sabatier, Université De Toulouse , Toulouse , France.

The synthesis of 14-(aryl)-14H-naphto[2,1-b]pyrano[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine-2-yl) acetamidoximes 2a-e has been accomplished by reaction of 2-acetonitrile derivatives 1a-e with hydroxylamine. Cyclocondensation reaction of precursors 2a-e with some elctrophilic species such as ethylorthoformate, acetic anhydride, and methyl-acetoacetate provided the new oxadiazole derivatives 3a-e, 4a-e, and 5a-e, respectively. On the other hand, the reaction of precursors 2a-e with 2-chloropropanoyl chloride afforded the new acetimidamides 6a-e which evolve under reflux of toluene to the new oxadiazoles 7a-e. The synthetic compounds were screened for their anti-xanthine oxidase, anti-soybean lipoxygenase, and cytotoxic activities. Moderate to weak xanthine oxidase and soybean lipoxygenase inhibitions were obtained but significant cytotoxic activities were noted. The most cytotoxic activities were recorded mainly (i) 5a was the most active (IC50 = 4.0 μM) and selective against MCF-7 and (ii) 2a was cytotoxic against the four cell lines with selectivity for MCF-7 and OVCAR-3 (IC50 = 17 and 12 μM, respectively) while 2e is highly selective against OVCAR-3 (IC50 = 10 μM).
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http://dx.doi.org/10.3109/14756366.2015.1118684DOI Listing
December 2016

Time-of-flight secondary ion mass spectrometry imaging of biological samples with delayed extraction for high mass and high spatial resolutions.

Rapid Commun Mass Spectrom 2015 Jul;29(13):1187-95

Institut de Chimie des Substances Naturelles, CNRS-ICSN UPR2301, Université Paris-Sud, Avenue de la Terrasse, 91198, Gif-sur-Yvette, France.

Rationale: In Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS), pulsed and focused primary ion beams enable mass spectrometry imaging, a method which is particularly useful to map various small molecules such as lipids at the surface of biological samples. When using TOF-SIMS instruments, the focusing modes of the primary ion beam delivered by liquid metal ion guns can provide either a mass resolution of several thousand or a sub-µm lateral resolution, but the combination of both is generally not possible.

Methods: With a TOF-SIMS setup, a delayed extraction applied to secondary ions has been studied extensively on rat cerebellum sections in order to compensate for the effect of long primary ion bunches.

Results: The use of a delayed extraction has been proven to be an efficient solution leading to unique features, i.e. a mass resolution up to 10000 at m/z 385.4 combined with a lateral resolution of about 400 nm. Simulations of ion trajectories confirm the experimental determination of optimal delayed extraction and allow understanding of the behavior of ions as a function of their mass-to-charge ratio.

Conclusions: Although the use of a delayed extraction has been well known for many years and is very popular in MALDI, it is much less used in TOF-SIMS. Its full characterization now enables secondary ion images to be recorded in a single run with a submicron spatial resolution and with a mass resolution of several thousand. This improvement is very useful when analyzing lipids on tissue sections, or rare, precious, or very small size samples.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5033000PMC
http://dx.doi.org/10.1002/rcm.7210DOI Listing
July 2015

Correlation between Density of CD8+ T-cell Infiltrate in Microsatellite Unstable Colorectal Cancers and Frameshift Mutations: A Rationale for Personalized Immunotherapy.

Cancer Res 2015 Sep 9;75(17):3446-55. Epub 2015 Jun 9.

Inserm U1079, Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France. Department of Genetics, Rouen University Hospital, Rouen, France.

Colorectal cancers with microsatellite instability (MSI) represent 15% of all colorectal cancers, including Lynch syndrome as the most frequent hereditary form of this disease. Notably, MSI colorectal cancers have a higher density of tumor-infiltrating lymphocytes (TIL) than other colorectal cancers. This feature is thought to reflect the accumulation of frameshift mutations in sequences that are repeated within gene coding regions, thereby leading to the synthesis of neoantigens recognized by CD8(+) T cells. However, there has yet to be a clear link established between CD8(+) TIL density and frameshift mutations in colorectal cancer. In this study, we examined this link in 103 MSI colorectal cancers from two independent cohorts where frameshift mutations in 19 genes were analyzed and CD3(+), CD8(+), and FOXP3(+) TIL densities were quantitated. We found that CD8(+) TIL density correlated positively with the total number of frameshift mutations. TIL densities increased when frameshift mutations were present within the ASTE1, HNF1A, or TCF7L2 genes, increasing even further when at least one of these frameshift mutations was present in all tumor cells. Through in vitro assays using engineered antigen-presenting cells, we were able to stimulate peripheral cytotoxic T cells obtained from colorectal cancer patients with peptides derived from frameshift mutations found in their tumors. Taken together, our results highlight the importance of a CD8(+) T cell immune response against MSI colorectal cancer-specific neoantigens, establishing a preclinical rationale to target them as a personalized cellular immunotherapy strategy, an especially appealing goal for patients with Lynch syndrome.
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http://dx.doi.org/10.1158/0008-5472.CAN-14-3051DOI Listing
September 2015

Semi-synthesis of new antimicrobial esters from the natural oleanolic and maslinic acids.

Food Chem 2015 Sep 14;183:8-17. Epub 2015 Mar 14.

Laboratoire de Chimie Hétérocyclique, Produits Naturels et Réactivité. Equipe: Chimie Médicinale et Produits Naturels, Département de Chimie, Faculté des Sciences de Monastir, Université de Monastir, Avenue de l'Environnement, 5019 Monastir, Tunisia.

In this article, we report an effective procedure for the selective isolation of oleanolic acid 1 and maslinic acid 2 (3.4 and 8.5mg/g DW, respectively) from pomace olive (Olea europaea L.) using an ultrasonic bath, and the synthesis of a series of new triterpenic acid esters. The compounds were characterized by their spectral data and were evaluated for their antimicrobial activity. Among the compounds tested, those having sulfur and chlorine atoms were found to be antibacterial. They showed activity against two Gram-positive bacteria Staphylococcus aureus and Enterococcus faecalis and two Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa (MICs within a range of 5-25μg/mL). The fungus Penicillium italicum was found to be the most sensitive to both sulfur derivatives: (3β)-3-((thiophene-2-carbonyl)oxy)-olean-12-en-28-oic acid (1a) (IZ=22mm) and (2α,3β-2,3-bis((thiophene-2-carbonyl)oxy)olean-12-en-28-oic acid (2a) (IZ=24mm).
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http://dx.doi.org/10.1016/j.foodchem.2015.03.018DOI Listing
September 2015

Building of a composite virtual slide from contiguous tissue samples.

Diagn Pathol 2014 19;9 Suppl 1:S9. Epub 2014 Dec 19.

Background: Currently available microscope slide scanners produce whole slide images at various resolutions from histological sections. Nevertheless, acquisition area and so visualization of large tissue samples are limited by the standardized size of glass slides, used daily in pathology departments. The proposed solution has been developed to build composite virtual slides from images of large tumor fragments.

Materials And Methods: Images of HES or immunostained histological sections of carefully labeled fragments from a representative slice of breast carcinoma were acquired with a digital slide scanner at a magnification of 20×. The tiling program involves three steps: the straightening of tissue fragment images using polynomial interpolation method, and the building and assembling of strips of contiguous tissue sample whole slide images in × and y directions. The final image is saved in a pyramidal BigTiff file format. The program has been tested on several tumor slices. A correlation quality control has been done on five images artificially cut.

Results: Sixty tumor slices from twenty surgical specimens, cut into two to twenty six pieces, were reconstructed. A median of 98.71% is obtained by computing the correlation coefficients between native and reconstructed images for quality control.

Conclusions: The proposed method is efficient and able to adapt itself to daily work conditions of classical pathology laboratories.
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http://dx.doi.org/10.1186/1746-1596-9-S1-S9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4305979PMC
May 2016

A methodology to ensure and improve accuracy of Ki67 labelling index estimation by automated digital image analysis in breast cancer tissue.

Breast Cancer Res 2014 ;16(2):R35

Introduction: Immunohistochemical Ki67 labelling index (Ki67 LI) reflects proliferative activity and is a potential prognostic/predictive marker of breast cancer. However, its clinical utility is hindered by the lack of standardized measurement methodologies. Besides tissue heterogeneity aspects, the key element of methodology remains accurate estimation of Ki67-stained/counterstained tumour cell profiles. We aimed to develop a methodology to ensure and improve accuracy of the digital image analysis (DIA) approach.

Methods: Tissue microarrays (one 1-mm spot per patient, n = 164) from invasive ductal breast carcinoma were stained for Ki67 and scanned. Criterion standard (Ki67-Count) was obtained by counting positive and negative tumour cell profiles using a stereology grid overlaid on a spot image. DIA was performed with Aperio Genie/Nuclear algorithms. A bias was estimated by ANOVA, correlation and regression analyses. Calibration steps of the DIA by adjusting the algorithm settings were performed: first, by subjective DIA quality assessment (DIA-1), and second, to compensate the bias established (DIA-2). Visual estimate (Ki67-VE) on the same images was performed by five pathologists independently.

Results: ANOVA revealed significant underestimation bias (P < 0.05) for DIA-0, DIA-1 and two pathologists' VE, while DIA-2, VE-median and three other VEs were within the same range. Regression analyses revealed best accuracy for the DIA-2 (R-square = 0.90) exceeding that of VE-median, individual VEs and other DIA settings. Bidirectional bias for the DIA-2 with overestimation at low, and underestimation at high ends of the scale was detected. Measurement error correction by inverse regression was applied to improve DIA-2-based prediction of the Ki67-Count, in particularfor the clinically relevant interval of Ki67-Count < 40%. Potential clinical impact of the prediction was tested by dichotomising the cases at the cut-off values of 10, 15, and 20%. Misclassification rate of 5-7% was achieved, compared to that of 11-18% for the VE-median-based prediction.

Conclusions: Our experiments provide methodology to achieve accurate Ki67-LI estimation by DIA, based on proper validation, calibration, and measurement error correction procedures, guided by quantified bias from reference values obtained by stereology grid count. This basic validation step is an important prerequisite for high-throughput automated DIA applications to investigate tissue heterogeneity and clinical utility aspects of Ki67 and other immunohistochemistry (IHC) biomarkers.
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http://dx.doi.org/10.1186/bcr3639DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4053156PMC
February 2015

Regulatory T lymphocytes are associated with less aggressive histologic features in microsatellite-unstable colorectal cancers.

PLoS One 2013 15;8(4):e61001. Epub 2013 Apr 15.

Inserm, U1079, Faculty of Medicine, Institute for Medical Research, Rouen University Hospital, Rouen, France.

Background: Colorectal cancers (CRCs) with microsatellite instability (MSI) are associated with a good prognosis and a high density of tumor-infiltrating lymphocytes (TILs). We have undertaken to determine the link between TIL densities and MSI CRC histologic features.

Patients And Methods: Using tissue microarrays, T-cell sub-population infiltration, including T cells (CD3), cytotoxic T cells (CD8) and regulatory T cells (FoxP3) were studied in 86 MSI CRCs. We separately analyzed TILs of the stromal and epithelial compartments in the tumor center, the tumoral invasion margin and associated normal tissue.

Results: For FoxP3+ TIL density in the tumor center stromal compartment, we found a strong negative correlation with T4 stage (p = 0.01), node invasion (p<0.001) and VELIPI (vascular emboli, lymphatic invasion and perinervous invasion) criteria (p = 0.002).

Conclusion: The strong correlation between regulatory T cell density and the absence of VELIPI criteria suggests that this sub-group of T cells is preferentially associated with less invasive tumors.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0061001PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3626697PMC
November 2013

Digital image analysis in pathology: benefits and obligation.

Anal Cell Pathol (Amst) 2012 ;35(2):75-8

National Center of Pathology, Affiliate of Vilnius University Hospital Santariskiu Klinikos, Vilnius, Lithuania.

Pathology has recently entered the era of personalized medicine. This brings new expectations for the accuracy and precision of tissue-based diagnosis, in particular, when quantification of histologic features and biomarker expression is required. While for many years traditional pathologic diagnosis has been regarded as ground truth, this concept is no longer sufficient in contemporary tissue-based biomarker research and clinical use. Another major change in pathology is brought by the advancement of virtual microscopy technology enabling digitization of microscopy slides and presenting new opportunities for digital image analysis. Computerized vision provides an immediate benefit of increased capacity (automation) and precision (reproducibility), but not necessarily the accuracy of the analysis. To achieve the benefit of accuracy, pathologists will have to assume an obligation of validation and quality assurance of the image analysis algorithms. Reference values are needed to measure and control the accuracy. Although pathologists' consensus values are commonly used to validate these tools, we argue that the ground truth can be best achieved by stereology methods, estimating the same variable as an algorithm is intended to do. Proper adoption of the new technology will require a new quantitative mentality in pathology. In order to see a complete and sharp picture of a disease, pathologists will need to learn to use both their analogue and digital eyes.
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http://dx.doi.org/10.3233/ACP-2011-0033DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4605791PMC
May 2012