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This article describes the chemical composition, physical properties and acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity of stem-distilled essential oil (EO) from Bursera graveolenswood chips, Burseraceae. The plant material was acquired in Quimis (Bosque de Sancán), city of Jipijapa in the province of Manabí, coastal region of Ecuador. Thirty-six components were identified by CG-MS, which represented 98.54% of the volatile oil. The main components were limonene (68.52%) and mentofuran (20.37%). The hydrocarbon monoterpenes constituted the most abundant fractions. The average yield of the EOwas 1.26%. Regarding the physical properties of EO, the following values were obtained: relative density (1,029 g/mL), refractive index (1,477) and specific rotation (+4,567). The EOpresented IC50inhibition values of 47.2 and 51.9 μg/mL for the enzymes AChE and BuChE, respectively.

Representative IHC staining of CD39 expression in human normal and tumor tissues (clone HPA014067).

Supplementary material and methods and supplementary figure legends.

Representative IHC staining of CD39 expression in vascular endothelial cells and lymphocytes from various normal tissues (clone 22A9).

The ectonucleotidases CD39 and CD73 hydrolyze extracellular adenosine triphosphate (ATP) and adenosine diphosphate (ADP) to generate adenosine, which binds to adenosine receptors and inhibits T-cell and natural killer (NK)–cell responses, thereby suppressing the immune system. The generation of adenosine via the CD39/CD73 pathway is recognized as a major mechanism of regulatory T cell (Treg) immunosuppressive function. The number of CD39+ Tregs is increased in some human cancers, and the importance of CD39+ Tregs in promoting tumor growth and metastasis has been demonstrated using several in vivo models. Here, we addressed whether CD39 is expressed by tumor cells and whether CD39+ tumor cells mediate immunosuppression via the adenosine pathway. Immunohistochemical staining of normal and tumor tissues revealed that CD39 expression is significantly higher in several types of human cancer than in normal tissues. In cancer specimens, CD39 is expressed by infiltrating lymphocytes, the tumor stroma, and tumor cells. Furthermore, the expression of CD39 at the cell surface of tumor cells was directly demonstrated via flow cytometry of human cancer cell lines. CD39 in cancer cells displays ATPase activity and, together with CD73, generates adenosine. CD39+CD73+ cancer cells inhibited the proliferation of CD4 and CD8 T cells and the generation of cytotoxic effector CD8 T cells (CTL) in a CD39- and adenosine-dependent manner. Treatment with a CD39 inhibitor or blocking antibody alleviated the tumor-induced inhibition of CD4 and CD8 T-cell proliferation and increased CTL- and NK cell–mediated cytotoxicity. In conclusion, interfering with the CD39–adenosine pathway may represent a novel immunotherapeutic strategy for inhibiting tumor cell–mediated immunosuppression. Cancer Immunol Res; 3(3); 254–65. ©2014 AACR.

CD39 ATPase activity can be assessed by measuring exogenous ATP consumption or phosphate release.

Validation of CD39 IHC.

Salvia pichinchensisBenth was collected in the South of Ecuador and the essential oil (EO) was distilled from aerial parts and analyzed by GC-MS and GC-FID. The physical properties, chemical composition, and cholinesterase inhibitory activity were determined. Six major components, all sesquiterpenes, were identified: cis-cadina-1(6),4-diene (17.11%) (1),γ-curcumene (13.75%) (2), (E)-caryophyllene (12.58%) (3), (E,E)-α-farnesene (10.00%) (4),α-gurjunene (9.46%) (5) and allo-aromadendrene (6.96%) (6). The EO showed an interesting selective inhibitory activity against the enzyme butyrylcholinesterase (50.70μg/mL) and only low inhibitory activity against acetylcholinesterase (117.60 μg/mL). The chemical composition and butyrylcholinesterase activity of the EO ofS. pichinchensisBenth was reported for first time.

International audience; Primary membranous nephropathy (MN) is an autoimmune glomerular disease in which autoantibodies are directed against podocyte proteins. In about 80% of cases the main targeted antigen is the phospholipase A2 receptor 1 (PLA2R1). Anti-PLA2R1 antibodies are mainly immunoglobulin G type 4 (IgG4). However, the antigenic target remains to be defined in 20% of cases. MN can be associated with chronic inflammatory demyelinating polyneuropathy, an autoimmune disease of the peripheral nervous system where a common antigenic target has yet to be identified. To ascertain a possible novel target antigen, we analyzed kidney biopsies from five patients positive for anti-contactin 1 antibodies and presenting with MN combined with chronic inflammatory demyelinating polyneuropathy. Eluted IgG from biopsy sections against contactin 1 and nerve tissue were screened. Western blot revealed contactin 1 expression in normal kidney glomeruli. Confocal microscopic analysis showed the presence and colocalization of contactin 1 and IgG4 on the glomerular basement membrane of these patients. Glomerular contactin 1 was absent in patients with anti-PLA2R1-associated MN or membranous lupus nephritis or a healthy control. The eluted IgG from contactin 1-positive biopsy sections but not the IgG eluted from patients with PLA2R1 MN bound conactin 1 with the main eluted subclass IgG4. Eluted IgG could bind paranodal tissue (myelinated axon) and colocalized with commercial anti-conactin 1 antibody. Thus, contactin 1 is a novel common antigenic target in MN associated with chronic inflammatory demyelinating polyneuropathy. However, the precise pathophysiology remains to be elucidated.

The pathogenicity of de novo donor-specific antibodies (dnDSA) varies according to their characteristics. While their MFI, complement-fixing ability, and IgG3 subclass are associated with ABMR occurrence and graft loss, they are not fully predictive of outcomes. We investigated the role of the Fc glycosylation of IgG3 dnDSA in ABMR occurrence using mass spectrometry after isolation by single HLA antigen beads. Between 2014 and 2018, we enrolled 54 patients who developed dnDSA (ABMR- n = 24; ABMR+ n = 30) in two French transplant centers. Fucosylation, galactosylation, GlcNAc bisection, and sialylation of IgG3 dnDSA were compared between ABMR+ and ABMR- patients. IgG3 dnDSA from ABMR+ patients exhibited significantly lower sialylation (7.5% vs. 10.5%, p .001) and higher GlcNAc bisection (20.6% vs. 17.4%, p = .008). Fucosylation and galactosylation were similar in both groups. DSA glycosylation was not correlated with DSA MFI. In a multivariate analysis, low IgG3 sialylation, high IgG3%, time from transplantation to kidney biopsy, and tacrolimus-free regimen were independent predictive factors of ABMR. We conclude that a proinflammatory glycosylation profile of IgG3 dnDSA is associated with a risk of ABMR occurrence. Further studies are needed to confirm the clinical interest of DSA glycosylation and to clarify its role in determining the risk of ABMR and graft survival.

This work aimed to study the chemical composition, cholinesterase inhibitory activity, and enantiomeric analysis of the essential oil from the aerial parts (leaves and flowers) of the plant Lepechinia paniculata (Kunth) Epling from Ecuador. The essential oil (EO) was obtained through steam distillation. The chemical composition of the oil was evaluated by gas chromatography, coupled to mass spectrometry (GC–MS) and a flame ionization detector (GC-FID). The analyses led to the identification of 69 compounds in total, of which 40 were found in the leaves and 29 were found in the flowers of the plant. The major components found in the oil were 1,8-Cineole, β-Pinene, δ-3-Carene, α-Pinene, (E)-Caryophyllene, Guaiol, and β-Phellandrene. Flower essential oil showed interesting selective inhibitory activity against both enzymes AChE (28.2 ± 1.8 2 µg/mL) and BuChE (28.8 ± 1.5 µg/mL). By contrast, the EO of the leaves showed moderate mean inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), with IC50 values of 38.2 ± 2.9 µg/mL and 47.4 ± 2.3 µg/mL, respectively.

The volatile constituents of the essential oil (EO) of Myrteola phylicoides (Benth) Landrum, from Ecuador, extracted by steam distillation have been analyzed. A total of 37 compounds, representing 90.30% the total essential oil sample were identified. Monoterpenes hydrocarbons (53.06%) and sesquiterpene hydrocarbons (35.24%) were the principal groups of compounds. The major components were identified as α-pinene (30.94%), (E)-caryophyllene (21.93%), β-pinene (14.45%) and α-humulene (9.56%). The essential oil of M. phylicoides showed weak in vitro activity against AChE inhibition with IC50 value 60.8 μg/mL and a low BChE activity with IC50 value >250 μg/mL. This is the first report on the chemical composition of the essential oil of this species.

The aim of our study was to investigate the impact of macroautophagy on exosome secretion. Exosomes are small membrane vesicles released in the extracellular space upon fusion of multivesicular endosomes with the plasma membrane. They were initially discovered as a way to remodel the reticulocyte plasma membrane before entering the blood circulation (Current Opinion in Hematology 2010, 17:177-183) and are now essentially studied as mediators of intercellular communication. Using iTRAQ proteomics, we compared the protein composition of purified exosomes secreted by cells impaired or not for macroautophagy by Atg5 depletion, during serum starvation conditions or complete medium culture. We show that the absence of serum modifies exosomal content, especially inducing secretion of two cytoplasmic protein complexes, namely proteasomal 19S regulatory particle (RP) and components of noncanonical translation preinitiation complex (PIC). This process is enhanced when autophagy is impaired by Atg5 depletion. Moreover, we show that the proteasome 20S core particle (CP) is released in the extracellular space. However, in striking contrast to what seen for its 19S RP regulator, release is independent of the exosomal vesicles, Atg5 expression and cell culture conditions. Exosome secretion can thus be considered as a cell process that participates in and reflects cell homeostasis, and care must be taken when studying potential extracellular function of exosomes due to the possible copurification of proteasome 20S CP.

This study aims at performing a chemical analysis of the essential oil (EO) of Ammodaucus leucotrichus Coss. & Dur. and investigating the anticholinesterase and anti-monoamine oxidase activities. The EO of the A. leucotrichus aerial part was analyzed by Gas Chromatography Mass Spectrometry (GC-MS). The inhibitory potency against Acetylcholinesterase (AChE) and Butyrylcholinesterase (BChE) were evaluated in vitro using modified Ellman's method. Monoamine oxidase activity was measured using the spectrophotometric method described by Weissbach. The chemical analysis of EO showed that the main constituents were perillaldehyde (by about 58.3%) and limonene (by about 23.33%). Further, the essential oil extracted from A. leucotrichus exhibited a promising anti-butyrylcholinesterase activity with an IC50 of about 95.2 μg/mL, where the perillaldehyde and limonene IC50 corresponded to 42.7 μg/mL and 66.7 μg/mL, respectively. The anti-acetylcholinesterase activity was observed only with limonene with IC50 = 51.6 μg/mL. The highest monoamine oxidase inhibitor activity was observed by essential oil followed by perillaldehyde. The oil demonstrated IC50 values for monoamine oxidase-B (MAO-B) of 40.5 μg/mL and 98.9 μg/mL for perillaldehyde. While, IC50 values for monoamine oxidase-A (MAO-A) were 112.5 μg/mL and 159.1 μg/mL for EO and perillaldehyde, respectively. No inhibitory activity against monoamine oxidase has been reported with limonene. A. leucotrichus C. & D. essential oil may represent an alternative source useful as a moderate anticholinesterase agent, particularly against butyrylcholinesterase and monoamine oxidase.

A novel chemical profile essential oil, distilled from the aerial parts of Clinopodium taxifolium (Kunth) Govaerts (Lamiaceae), was analysed by Gas Chromatography-Mass Spectrometry (GC-MS, qualitative analysis) and Gas Chromatography with Flame Ionization Detector (GC-FID, quantitative analysis), with both polar and non-polar stationary phase columns. The chemical composition mostly consisted of sesquiterpenes and sesquiterpenoids (&gt, 70%), the main ones being (E)-&beta, caryophyllene (17.8%), &alpha, copaene (10.5%), &beta, bourbonene (9.9%), &delta, cadinene (6.6%), cis-cadina-1(6),4-diene (6.4%) and germacrene D (4.9%), with the non-polar column. The essential oil was then submitted to enantioselective GC analysis, with a diethyl-tert-butyldimethylsilyl-&beta, cyclodextrin diluted in PS-086 chiral selector, resulting in the following enantiomeric excesses for the chiral components: (1R,5S)-(&minus, )-&alpha, thujene (67.8%), (1R,5R)-(+)-&alpha, pinene (85.5%), (1S,5S)-(&minus, )-&beta, pinene (90.0%), (1S,5S)-(&minus, )-sabinene (12.3%), (S)-(&minus, )-limonene (88.1%), (S)-(+)-linalool (32.7%), (R)-(&minus, )-terpinen-4-ol (9.3%), (S)-(&minus, terpineol (71.2%) and (S)-(&minus, )-germacrene D (89.0%). The inhibition activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) of C. taxifolium essential oil was then tested, resulting in selective activity against BChE with an IC50 value of 31.3 &plusmn, 3.0 &mu, g/mL (positive control: donepezil, IC50 = 3.6 &mu, g/mL).

Ethnobotanical and ethnomedicinal relevance In southern Ecuador, horchata lojana is a popular aromatic and refreshing beverage that is prepared from an aqueous infusion of different mixtures of local medicinal and aromatic plants. The drink is considered a traditional anti-inflammatory agent and brain tonic; due these properties, it has been drunk since Colonial Times. Several pharmacological studies have evaluated the effects of horchata aqueous infusion. However, the aromatic profile and the contribution of the volatile components to the biological activity of the drink have not been investigated so far. For these reasons, we have determined the chemical composition of the essential oils (EOs) distilled from five mixtures of aromatic plants commonly used for the preparation of this traditional drink. Moreover, to support the curative properties of the aromatic plants, the anticholinesterase activity of the EOs was examined. Material and methods Different bunches of fresh mixed medicinal and aromatic plants, called tongos, are sold at local markets in the province of Loja for the preparation of different types of horchata. In this research we have purchased plant bunches sold at five popular markets of Loja province. Subsequently, aromatic plants in each bunch were separated from medicinal plants and were then hydrodistilled to give the corresponding EOs. Subsequently, the chemical composition of each EO was determined by GC-MS/GC–FID techniques, whereas the cholinesterase inhibitory activity in vitro was determined against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. Aims of the study i) to contribute to the chemical and pharmacological study of the aroma components of the traditional Ecuadorian drink horchata lojana; ii) to identify botanically the mixtures of aromatic plants used to make the drink; iii) to establish, on the basis of the chemical composition of the EOs, the compounds mainly responsible for the characteristic beverage flavor; iv) to establish the possible existence of an aromatic pattern characteristic of each horchata preparation; v) to test the anticholinesterase activity of the EOs against AChE and BuChE in order to support the traditional consume of the drink as an effective brain tonic. Results A total of 23 botanical families and 32 species of plants used for the preparation of five different variants of the traditional horchata lojana beverage, have been identified. Fourteen aromatic species were determined to be responsible for the characteristic flavor of the drink. All the analyzed EOs belong to the monoterpene type. A total of 88 compounds have been identified in the different EOs, twenty-four of which are common components of the oils. Conclusions According to the main components of the EOs distilled from the five groups of horchata lojana plants, four aromatic profiles have been defined: (i) neral + geranial + carvone, (ii) neral + geranial + myrcene; (iii) geranial + methyl eugenol + isomenthone + neral + citronellol; (iv) (E)-anethole + geranial + pulegone. Moreover, according to the literature, several aromatic plants and individual EOs components exhibit a wide range of biological activities. This finding as well as the significant BuChE inhibitory activity exhibited in vitro by the EOs give scientific support to the use of identified aromatic plants in the traditional preparation of horchata, that is considered a natural analgesic and anti-inflammatory remedy, and an effective brain tonic.

Donor-specific antibodies (DSAs) are the main risk factor for antibody-mediated rejection (ABMR) and graft loss but could have variable pathogenicity according to their IgG subclass composition. Luminex-based test might lack sensitivity for the detection of IgG subclasses and this test does not allow quantifying the relative abundance of each IgG subclass. We investigated the precise repartition of each DSA subclass and their role in ABMR occurrence and severity, using an innovative mass spectrometry-based method. Between 2014 and 2018, we enrolled 69 patients who developed de novo DSA (n = 29 without ABMR, and n = 40 with ABMR) in two transplant centers. All IgG subclasses were detected in every samples tested: 62.7% were IgG1, 26.6% were IgG2, 6.6% were IgG3, and 4.2% were IgG4. The IgG3 proportion was significantly higher in the ABMR+ compared to the ABMR– group (8.4% vs. 5.6%, p = 0.003). The proportion of IgG1, IgG2, and IgG4 of DSA was similar between the two groups. Higher IgG3 level was associated with higher C4d deposition, higher microvascular inflammation scores, and glomerular filtration rate decline >25%. IgG3 proportion was not correlated with DSA MFI. Multivariate analysis showed that proteinuria and high level of IgG3 DSA were the only two factors independently associated with ABMR. In conclusion, de novo DSA are always composed of the four IgG subclasses, but in different proportions. High IgG3 proportion is associated with ABMR occurrence and severity and with poorer outcome, independently of DSA MFI.

Lepechinia mutica (Benth.) Epling, Lamiaceae, and Vallea stipularis L.f., Elaeocarpaceae, are the object of the present study. These plants are endemic to the Andean region and have attracted our attention on the basis of interesting results obtained in a preliminary anticholinesterase screening. Actually, carnosol and tiliroside, isolated from L. mutica and V. stipularis, respectively, have shown a promising selective inhibitory activity against butyrylcholinesterase. Specifically, the anti-butyrylcholinesterase activity of carnosol was 5.15 μM and that of tiliroside was 52.9 μM, compared to 8.568 ± 0.570 μM of the positive control Donepezil. Carnosol and tiliroside were purified chromatographically from the ethyl acetate extract of L. mutica and V. stipularis, respectively. Spectrophotometric methods were used for enzymatic studies. Keywords: Ecuador, Carnosol, Tiliroside, BuChE inhibitory activity, Enzymatic studies, Anticholinesterase screening

The fresh leaves of Coreopsis triloba S.F. Blake, collected at Cerro Villonaco in Loja, Ecuador, were investigated with respect to their essential oil (EO). The chemical composition was determined qualitatively through gas chromatography coupled with mass spectrometry (GC-MS) and quantitatively by gas chromatography coupled with flame ionization (GC-FID), using relative response factors (RRF) based on the enthalpy of combustion. The essential oil contained between 92.5% and 93.4% of monoterpene hydrocarbons, with(E)-&beta, ocimene being the main component (35.2&ndash, 35.9%), followed by &beta, phellandrene (24.6&ndash, 25.0%), &alpha, pinene (15.3&ndash, 15.9%), myrcene (10.9&ndash, 11.0%), sabinene (2.2&ndash, 2.4%), (Z)-&beta, ocimene (1.5%), and germacrene D (1.2&ndash, 1.3%). The enantiomeric distribution of &alpha, pinene, &beta, pinene, limonene, and germacrene D was also determined. The main components responsible for the aroma were identified through aroma extract dilution analysis (AEDA), a gas chromatography-olfactometry (GC-O) based technique, being &alpha, pinene (0.6%), terpinolene (0.1%), &alpha, copaene (0.1&ndash, 0.3%), &beta, phellandrene, and (E)-4,8-dimethyl-1,3,7-nonatriene (0.1&ndash, 0.2%) the main olfactory constituents according to the decreasing factor of dilution (FD) order. The biological tests showed IC50 inhibition values of 42.2 and 6.8 &micro, g/mL for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), respectively.

International audience; The characterization of cancer tissues by matrix-assisted laser desorption ionization-mass spectrometry images (MALDI-MSI) is of great interest because of the power of MALDI-MS to understand the composition of biological samples and the imaging side that allows for setting spatial boundaries among tissues of different nature based on their compositional differences.In tissue-based cancer research, information on the spatial location of necrotic/tumoral cell populations can be approximately known from grayscale images of the scanned tissue slices. This study proposes as a major novelty the introduction of this physiologically-based information to help in the performance of unmixing methods, oriented to extract the MS signatures and distribution maps of the different tissues present in biological samples. Specifically, the information gathered from grayscale images will be used as a local rank constraint in Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) for the analysis of MALDI-MSI of cancer tissues. The use of this constraint, setting absence of certain kind of tissues only in clear zones of the image, will help to improve the performance of MCR-ALS and to provide a more reliable definition of the chemical MS fingerprint and location of the tissues of interest.The general strategy to address the analysis of MALDI-MSI of cancer tissues will involve the study of the MCR-ALS results and the posterior use of MCR-ALS scores as dimensionality reduction for image segmentation based on K-means clustering. The resolution method will provide the MS signatures and their distribution maps for each tissue in the sample. Then, the resolved distribution maps for each biological component (MCR scores) will be submitted as initial information to K-means clustering for image segmentation to obtain information on the boundaries of the different tissular regions in the samples studied. MCR-ALS prior to K-means not only provides the desired dimensionality reduction, but additionally resolved non-biological signal contributions are not used and the weight given to the different biological components in the segmentation process can be modulated by suitable preprocessing methods.

SummaryDuring transcription and DNA replication, the DNA template is overwound ahead of RNA and DNA polymerases and relaxed by DNA topoisomerases. Inhibitors of topoisomerases are potent anti-cancer agents. Camptothecin traps topoisomerase I on DNA and exerts preferential cytotoxicity toward cancer cells by way of its interference with the progression of replication forks. Starting with an unbiased proteomic analysis, we find that the chromatin remodeling complex BAZ1B-SMARCA5 accumulates near replication forks in camptothecin-exposed cells. We report that BAZ1B associates with topoisomerase I and facilitates its access to replication forks. Single-molecule analyses of replication structures show that BAZ1B contributes to replication interference by camptothecin. A lack of BAZ1B confers increased cellular tolerance of camptothecin. These findings reveal BAZ1B as a key facilitator of topoisomerase I function during DNA replication that affects the response of cancer cells to topoisomerase I inhibitors.

Intratumour heterogeneity due to cancer cell clonal evolution and microenvironment composition and tumor differences due to genetic variations between patients suffering of the same cancer pathology play a crucial role in patient response to therapies. This study is oriented to show that matrix-assisted laser-desorption ionization-Mass spectrometry imaging (MALDI-MSI), combined with an advanced multivariate data processing pipeline can be used to discriminate subtle variations between highly similar colorectal tumors. To this aim, experimental tumors reproducing the emergence of drug-resistant clones were generated in athymic mice using subcutaneous injection of different mixes of two isogenic cell lines, the irinotecan-resistant HCT116-SN50 (R) and its sibling human colon adenocarcinoma sensitive cell line HCT116 (S). Because irinotecan-resistant and irinotecan-sensitive are derived from the same original parental HCT116 cell line, their genetic characteristics and molecular compositions are closely related. The multivariate data processing pipeline proposed relies on three steps: (a) multiset multivariate curve resolution (MCR) to separate biological contributions from background; (b) multiset K-means segmentation using MCR scores of the biological contributions to separate between tumor and necrotic parts of the tissues; and (c) partial-least squares discriminant analysis (PLS-DA) applied to tumor pixel spectra to discriminate between R and S tumor populations. High levels of correct classification rates (0.85), sensitivity (0.92) and specificity (0.77) for the PLS-DA classification model were obtained. If previously labelled tissue is available, the multistep modeling strategy proposed constitutes a good approach for the identification and characterization of highly similar phenotypic tumor subpopulations that could be potentially applicable to any kind of cancer tissue that exhibits substantial heterogeneity.

The essential oils of Myrcianthes myrsinoides and Myrcia mollis, belonging to the Myrtaceae family, were obtained by steam distillation. They were analyzed by gas chromatography-mass spectrometry (GC-MS), gas chromatography-flame ionization detector (GC-FID), enantioselective gas chromatography, and gas chromatography-olfactometry (GC-O). A total of 58 compounds for Myrcianthes myrsinoides essential oil (EO) and 22 compounds for Myrcia mollis EO were identified and quantified by GC-MS with apolar and polar columns (including undetermined components). Major compounds (&gt, 5.0%) were limonene (5.3%&ndash, 5.2%), 1,8-cineole (10.4%&ndash, 11.6%), (Z)-caryophyllene (16.6%&ndash, 16.8%), trans-calamenene (15.9%&ndash, 14.6%), and spathulenol (6.2%&ndash, 6.5%). The enantiomeric excess of eight chiral constituents was determined, being (+)-limonene and (+)-germacrene D enantiomerically pure. Eight components were identified as determinant in the aromatic profile: &alpha, pinene, &beta, pinene, (+)-limonene, &gamma, terpinene, terpinolene, linalool, &beta, elemene and spathulenol. For M. mollis, the major compounds (&gt, 5.0%) were &alpha, pinene (29.2%&ndash, 27.7%), &beta, pinene (31.3%&ndash, 30.0%), myrcene (5.0%&ndash, 5.2%), 1,8-cineole (8.5%&ndash, 8.7%), and linalool (7.7%&ndash, 8.2%). The enantiomeric excess of five chiral constituents was determined, with (S)-&alpha, pinene and (+)-germacrene D enantiomerically pure. The metabolites &beta, pinene, 1,8-cineole, &gamma, terpinene, terpinolene, linalool, and (E)-&beta, caryophyllene were mainly responsible for the aroma of the EO. Finally, the M. myrsinoides essential oil has an inhibitory activity for cholinesterase enzymes (IC50 of 78.6 &mu, g/ml and 18.4 &mu, g/ml vs. acethylcholinesterase (AChE) and butyrylcholinesterase (BChE) respectively). This activity is of interest to treat Alzheimer&rsquo, s disease.

International audience; This study investigated the chemical composition, physical proprieties, biological activity, and enantiomeric analysis of the essential oil from the aerial parts of Niphogeton dissecta (culantrillo del cerro) from Ecuador, obtained by steam distillation. The qualitative and quantitative analysis of the essential oil was realized by gas chromatographic and spectroscopic techniques (GC-MS and GC-FID). Acorenone B was identified by GC-MS and NMR experiments. The enantiomeric distribution of some constituents has been assessed by enantio-GC through the use of a chiral cyclodextrin-based capillary column. We identified 41 components that accounted for 96.46% of the total analyzed, the major components were acorenone B (41.01%) and (E)-β-ocimene (29.64%). The enantiomeric ratio of (+)/(-)-β-pinene was 86.9:13.1, while the one of (+)/(-)-sabinene was 80.9:19.1. The essential oil showed a weak inhibitory activity, expressed as Minimal Inhibitory Concentration (MIC), against Enterococcus faecalis (MIC 10 mg/mL) and Staphylococcus aureus (MIC 5 mg/mL). Furthermore, it inhibited butyrylcholinesterase with an IC50 value of 11.5 μg/mL. Pure acorenone B showed inhibitory activity against both acetylcholinesterase and butyrylcholinesterase, with IC50 values of 40.8 μg/mL and 10.9 μg/mL, respectively.

The ectonucleotidases CD39 and CD73 hydrolyze extracellular adenosine triphosphate (ATP) and adenosine diphosphate (ADP) to generate adenosine, which binds to adenosine receptors and inhibits T-cell and natural killer (NK)–cell responses, thereby suppressing the immune system. The generation of adenosine via the CD39/CD73 pathway is recognized as a major mechanism of regulatory T cell (Treg) immunosuppressive function. The number of CD39+ Tregs is increased in some human cancers, and the importance of CD39+ Tregs in promoting tumor growth and metastasis has been demonstrated using several in vivo models. Here, we addressed whether CD39 is expressed by tumor cells and whether CD39+ tumor cells mediate immunosuppression via the adenosine pathway. Immunohistochemical staining of normal and tumor tissues revealed that CD39 expression is significantly higher in several types of human cancer than in normal tissues. In cancer specimens, CD39 is expressed by infiltrating lymphocytes, the tumor stroma, and tumor cells. Furthermore, the expression of CD39 at the cell surface of tumor cells was directly demonstrated via flow cytometry of human cancer cell lines. CD39 in cancer cells displays ATPase activity and, together with CD73, generates adenosine. CD39+CD73+ cancer cells inhibited the proliferation of CD4 and CD8 T cells and the generation of cytotoxic effector CD8 T cells (CTL) in a CD39- and adenosine-dependent manner. Treatment with a CD39 inhibitor or blocking antibody alleviated the tumor-induced inhibition of CD4 and CD8 T-cell proliferation and increased CTL- and NK cell–mediated cytotoxicity. In conclusion, interfering with the CD39–adenosine pathway may represent a novel immunotherapeutic strategy for inhibiting tumor cell–mediated immunosuppression. Cancer Immunol Res; 3(3); 254–65. ©2014 AACR.

International audience; Displaying a strong antiproliferative activity on a wide variety of cancer cells, EAPB0203 and EAPB0503 belong to the imidazo[1,2-a]quinoxalines family of imiquimod structural analogues. EAPB0503 has been shown to inhibit tubulin polymerization. The aim of the present study is to characterize the interaction of EAPB0203 and EAPB0503 with tubulin. We combine experimental approaches at the cellular and the molecular level both in vitro and in silico in order to evaluate the interaction of EAPB0203 and EAPB0503 with tubulin. We examine the influence of EAPB0203 and EAPB0503 on the cell cycle and fate, explore the binding interaction with purified tubulin, and use a computational molecular docking model to determine the binding modes to the microtubule. We then use a drug combination study with other anti-microtubule agents to compare the binding site of EAPB0203 and EAPB0503 to known potent tubulin inhibitors. We demonstrate that EAPB0203 and EAPB0503 are capable of blocking human melanoma cells in G2 and M phases and inducing cell death and apoptosis. Second, we show that EAPB0203 and EAPB0503, but also unexpectedly imiquimod, bind directly to purified tubulin and inhibit tubulin polymerization. As suggested by molecular docking and binding competition studies, we identify the colchicine binding site on β-tubulin as the interaction pocket. Furthermore, we find that EAPB0203, EAPB0503 and imiquimod display antagonistic cytotoxic effect when combined with colchicine, and disrupt tubulin network in human melanoma cells. We conclude that EAPB0203, EAPB0503, as well as imiquimod, interact with tubulin through the colchicine binding site, and that the cytotoxic activity of EAPB0203, EAPB0503 and imiquimod is correlated to their tubulin inhibiting effect. These compounds appear as interesting anticancer drug candidates as suggested by their activity and mechanism of action, and deserve further investigation for their use in the clinic.

Proteins disabled in Fanconi anemia (FA) are necessary for the maintenance of genome stability during cell proliferation. Upon replication stress signaling by ATR, the FA core complex monoubiquitinates FANCD2 and FANCI in order to activate DNA repair. Here, we identified FANCD2 and FANCI in a proteomic screen of replisome-associated factors bound to nascent DNA in response to replication arrest. We found that FANCD2 can interact directly with minichromosome maintenance (MCM) proteins. ATR signaling promoted the transient association of endogenous FANCD2 with the MCM2-MCM7 replicative helicase independently of FANCD2 monoubiquitination. FANCD2 was necessary for human primary cells to restrain DNA synthesis in the presence of a reduced pool of nucleotides and prevented the accumulation of single-stranded DNA, the induction of p21, and the entry of cells into senescence. These data reveal that FANCD2 is an effector of ATR signaling implicated in a general replisome surveillance mechanism that is necessary for sustaining cell proliferation and attenuating carcinogenesis.