Functional analysis of dual-specificity protein phosphatases in angiogenesis
; ERPICUM, Charlotte ; Gilles, Christine et al
in Pulido, Rafael (Ed.) Protein Tyrosine Phosphatases: Methods and Protocols (in press)
Therapeutic perspectives targeting angiogenesis in cancer stimulated an intense investigation of the mechanisms triggering and governing angiogenic processes. Several publications have highlighted the ... [more ▼]
Therapeutic perspectives targeting angiogenesis in cancer stimulated an intense investigation of the mechanisms triggering and governing angiogenic processes. Several publications have highlighted the importance of typical dual-specificity phosphatases (DSPs) or MKPs in endothelial cells and their role in controlling different biological functions implicated in angiogenesis such as migration, proliferation, apoptosis, tubulogenesis and cell adhesion. However, among atypical DSPs, the only one investigated in angiogenesis was DUSP3. We recently identified this DSP as new key player in endothelial cells and angiogenesis. In this chapter we provide with detailed protocols and models used to investigate the role of DUSP3 in endothelial cells and angiogenesis. We start the chapter with an overview of the role of several DSPs in angiogenesis. We continue with providing a full description of a highly efficient transfection protocol to deplete DUSP3 using small interfering RNA (siRNA) in the primary Human Umbilical Vein Endothelial Cells (HUVEC). We next describe the major assays used to investigate different processes involved in angiogenesis such as tube formation assay, proliferation assay and spheroids sprouting assay. We finish the chapter by validating our results in DUSP3-knockout mice using in vivo angiogenesis assays such as Matrigel plug and Lewis lung carcinoma cell subcutaneous xenograft model followed by anti-CD31 immunofluorescence and ex vivo aortic ring assay. All methods described can be adapted to other phosphatases and signaling molecules. [less ▲]Detailed reference viewed: 53 (8 ULg)
Feasibility study of repetitive diffusion MRI after Neoadjuvant radiotherapy for following tumor microenvironment.
LALLEMAND, François ; Leroi, Natacha ; Bahri, Mohamed Ali et al
Conference (2016, March 22)
Purpose/Objective. Neoadjuvant radiotherapy (NeoRT) improves tumor local control and tumor resection in many cancers. The timing between the end of the NeoRT and surgery is mostly driven by the occurrence ... [more ▼]
Purpose/Objective. Neoadjuvant radiotherapy (NeoRT) improves tumor local control and tumor resection in many cancers. The timing between the end of the NeoRT and surgery is mostly driven by the occurrence of side effects or the tumor downsizing. We previously demonstrated in an in vivo model that the timing of surgery and the schedule of NeoRT influenced the tumor dissemination. Here, our aim is to evaluate with functional MRI (fMRI) the impact of the radiation treatment on the tumor microenvironment and subsequently to identify non-invasive markers helping to determine the best timing to perform surgery for avoiding tumor spreading. First, we needed to demonstrate the feasibility of repetitive MRI imaging after NeoRT in mice. Material/methods. We used two models of NeoRT we previously developed in mice: MDA-MB 231 and 4T1 cells implanted in the flank of mice. When tumors reached the planned volume, they are irradiated with 2x5 Gy and then surgically removed at different time points after RT. In the mean time between the end of RT and the surgical procedure, mice were imaged in a 9,4T Agilent® MRI. Diffusion Weighted (DW) -MRI was performed every 2 days between RT and surgery. For each tumors we acquired 8 slices of 1 mm thickness and 0.5 mm gap with an “in plane voxel resolution” of 0.5 mm. For DW-MRI, we performed FSEMS (Fast Spin Echo MultiSlice) sequences, with 9 different B-values (from 40 to 1000) and B0, in the 3 main directions. We also performed IVIM (IntraVoxel Incoherent Motion) analysis, in the aim to obtain information on intravascular diffusion, related to perfusion (F: perfusion factor) and subsequently tumor vessels perfusion. Results. As preliminary results, with the MBA-MB 231 we observed a significant increase of F at day 6 after irradiation than a decrease and stabilization until surgery. No other modifications of the MRI signal, ADC, D or D* were observed. We observed similar results with 4T1 cells, F increased at day 3 than returned to initial signal. The difference in the timing of the peak of F can be related to the difference in tumor growth between MBA-MB 231 and 4T1 (four weeks vs one week). Conclusion. For the first time, we demonstrate the feasibility of repetitive fMRI imaging in mice models after NeoRT. With these models, we show a significant peak of the perfusion factor (F) at day 6 or day 3. This change occurs between the two previous time points of surgery demonstrating a difference in the metastatic spreading. Indeed, after a NeoRT of 2X5Gy we observed more metastases in the lung when MDA-MB 231 tumor bearing mice are operated 4 days after RT compared to 11 days. These preliminary results are very promising for identifying noninvasive markers for determining the best timing for surgery. [less ▲]Detailed reference viewed: 21 (6 ULg)
Estetrols’ Potential for Neuroprotection Following the injury to the Developing Brain: Preclinical Studies
Tskitishvili, Ekaterine ; Nisolle, Michelle ; Noël, Agnès et al
in The 17th World Congress of Gynecological Endocrinology, Florence 2-5 March 2016 (2016, March)
Context: Hypoxic-Ischemic encephalopathy (HIE) remains a major cause of perinatal brain injury. The brain rapidly increases in size, shape and complexity during the second and third trimesters. A sentinel ... [more ▼]
Context: Hypoxic-Ischemic encephalopathy (HIE) remains a major cause of perinatal brain injury. The brain rapidly increases in size, shape and complexity during the second and third trimesters. A sentinel event in late pregnancy or the intrapartum period may have an acute profound effect on a previously neurologically intact fetus, leading to the development of (HIE). The nature of the deficits is dependent on the gestational age and severity of the insult, though it is seldom reported in preterm infants. Studies in animal models of HIE may provide important information for the development of treatment for this pathological condition. Estetrol (E4) is a recently described estrogen with four hydroxyl-groups that is synthesized exclusively during pregnancy by the human fetal liver. Objective: In this study, we evaluated E4’s neuroprotective and therapeutic potency in neonatal (in vivo) HIE model of the immature 7-day-old newborn rat. Methods: Rat pups body temperatures were examined along with their body and brain weights. Brains were studied at the level of the hippocampus and cortex. Intact cell counting and expressions of markers for neuronal early grey matter damage (microtubule-associated protein-2 (MAP-2)), neurogenesis (doublecortin (DCX)) and angiogenesis (vascular-endothelial growth factor (VEGF)) were evaluated by histo- and immunohistochemistry. The serum levels of two markers of brain damage (S100B and glial fibrillary acidic protein (GFAP)) were measured by ELISA. Results: Our results demonstrate that E4 has a significant neuroprotective and therapeutic effects. Estetrol decreases the early gray matter loss, and promotes neuro- and angiogenesis in vivo. Estetrol treatment has no effects on body weight, brain weight or body temperature. Conclusion: Taken together, E4 might become an important safe and physiological substance to treat neonatal HIE. [less ▲]Detailed reference viewed: 19 (1 ULg)
Dynamics of Internalization and Recycling of the Pro-Metastatic Membrane Type 4-Matrix Metalloproteinase (MT4-MMP) in Breast Cancer Cells
Truong, Alice ; Yip, Cassandre ; PAYE, Alexandra et al
in FEBS Journal (2016), 283(4), 704-22
MT4-MMP (MMP17) is a glycosylphosphatidyl inositol (GPI)-anchored membrane-type MMP expressed on the cell surface of human breast cancer cells. In triple negative breast cancer cells, MT4-MMP promotes ... [more ▼]
MT4-MMP (MMP17) is a glycosylphosphatidyl inositol (GPI)-anchored membrane-type MMP expressed on the cell surface of human breast cancer cells. In triple negative breast cancer cells, MT4-MMP promotes primary tumor growth and lung metastases. Although trafficking and internalization of the transmembrane MT1-MMP have been extensively investigated, little is known about the regulatory mechanisms of the GPI-anchored MT4-MMP. Here, we investigated the fate and cellular trafficking of MT4-MMP by analyzing its homophilic complex interactions, internalization and recycling dynamics compared to an inert form, MT4-MMP-E249A. Oligomeric and dimeric complexes were analyzed by co-transfection of cells with FLAG- or Myc-tagged MT4-MMP by reducing and non-reducing immunoblots and co-immunoprecipitation experiments. The trafficking of MT4-MMP was studied using an antibody feeding assay and confocal microscopy analysis or cell surface protein biotinylation and Western blot analysis. We demonstrate that MT4-MMP forms homophilic complexes at the cell surface, internalizes in early endosomes, and some of the enzyme is either auto-degraded or recycled to the cell surface. Our data indicate that MT4-MMP is internalized by the CLIC/GEEC pathway, a mechanism that differs from other MT-MMP members. Although MT4-MMP localizes with caveolin-1, MT4-MMP internalization was not affected by inhibitors of caveolin-1 or clathrin endocytosis pathways but was reduced by cdc42 or RhoA silencing with siRNA. We provide a new mechanistic insight into the regulatory mechanisms of MT4-MMP, which may have implications in the design of novel therapeutic strategies for metastatic breast cancer. This article is protected by copyright. All rights reserved. [less ▲]Detailed reference viewed: 60 (11 ULg)
Regulation of Tissue Factor by Epithelial-to-Mesenchymal Transitions: Impacts for the metastatic progression.
Francart, Marie-Emilie ; Bourcy, Morgane ; Lambert, Justine et al
Poster (2016, January 25)Detailed reference viewed: 8 (0 ULg)
Implication of Epithelial-to-Mesenchymal Transitions (EMTs) on the formation of vascular nests for Circulating Tumor Cells (CTCs) : focus on CD44 as a fibrin(ogen) receptor.
Lambert, Justine ; Bourcy, Morgane ; Francart, Marie-Emilie et al
Poster (2016, January 25)Detailed reference viewed: 14 (1 ULg)
Epithelial-mesenchymal transition induces tissue factor and pro-coagulant properties supporting early metastasis of circulating tumor cells.
Bourcy, Morgane ; ; Lambert, Justine et al
Poster (2016, January)Detailed reference viewed: 14 (1 ULg)
Elastin density: Link between histological and biomechanical properties of vaginal tissue in women with pelvic organ prolapse?
DE LANDSHEERE, Laurent ; ; Blacher, Silvia et al
in International Urogynecology Journal & Pelvic Floor Dysfunction (2016)
INTRODUCTION AND HYPOTHESIS: The aim of the study was to correlate histological and biomechanical characteristics of the vaginal wall in women with pelvic organ prolapse (POP). METHODS: Tissue samples ... [more ▼]
INTRODUCTION AND HYPOTHESIS: The aim of the study was to correlate histological and biomechanical characteristics of the vaginal wall in women with pelvic organ prolapse (POP). METHODS: Tissue samples were collected from the anterior [point Ba; POP Questionnaire (POP-Q)] and/or posterior (point Bp; POP-Q) vaginal wall of 15 women who underwent vaginal surgery for POP. Both histological and biomechanical assessments were performed from the same tissue samples in 14 of 15 patients. For histological assessment, the density of collagen and elastin fibers was determined by combining high-resolution virtual imaging and computer-assisted digital image analysis. For biomechanical testing, uniaxial tension tests were performed to evaluate vaginal tissue stiffness at low (C0) and high (C1) deformation rates. RESULTS: Biomechanical testing highlights the hyperelastic behavior of the vaginal wall. At low strains (C0), vaginal tissue appeared stiffer when elastin density was low. We found a statistically significant inverse relationship between C0 and the elastin/collagen ratio (p = 0.048) in the lamina propria. However, at large strain levels (C1), no clear relationship was observed between elastin density or elastin/collagen ratio and stiffness, likely reflecting the large dispersion of the mechanical behavior of the tissue samples. CONCLUSION: Histological and biomechanical properties of the vaginal wall vary from patient to patient. This study suggests that elastin density deserves consideration as a relevant factor of vaginal stiffness in women with POP. [less ▲]Detailed reference viewed: 16 (2 ULg)
Supplementation of transport and freezing media with anti-apoptotic drugs improves ovarian cortex survival
HENRY, Laurie ; Fransolet, Maïté ; LABIED, Soraya et al
in Journal of Ovarian Research (2016)
Background: Ovarian tissue preservation is proposed to patients at risk of premature ovarian failure, but this procedure still needs to be optimized. To limit injury during ovarian tissue cryopreservation ... [more ▼]
Background: Ovarian tissue preservation is proposed to patients at risk of premature ovarian failure, but this procedure still needs to be optimized. To limit injury during ovarian tissue cryopreservation, anti-apoptotic drugs were added to the transport and freezing media of ovarian cortex tissue. Methods: Sheep ovaries were transported, prepared and frozen in solutions containing vehicle or anti-apoptotic drugs (Z-VAD-FMK, a pan-caspase inhibitor, or sphingosine-1-phosphate (S1P), a bioactive lipid). After the tissue was thawed, the ovarian cortex was cultured for 2 or 6 days. Follicular quantification and morphological and proliferation analyses were performed on histological sections. Results: After 2 days of culture, S1P improved the quality of primordial follicles; higher densities of morphologically normal and proliferative primordial follicles were found. Z-VAD-FMK displayed similar effects by preserving global primordial follicular density, but this effect was evident after 6 days of culture. This drug also improved cell proliferation after 2 and 6 days of culture. Conclusions: Our results showed that the addition of S1P or Z-VAD-FMK to the transport and freezing media prior to ovarian tissue cryopreservation improves primordial follicular quality and therefore improves global tissue survival. This should ultimately lead to improved fertility restoration after auto-transplantation. [less ▲]Detailed reference viewed: 18 (1 ULg)
Quantitative assessment of mouse mammary gland morphology using automated digital image processing and TEB detection.
Blacher, Silvia ; Gérard, Céline ; Gallez, Anne et al
in Endocrinology (2016)
The assessment of rodent mammary gland morphology is largely used to study the molecular mechanisms driving breast development and to analyze the impact of various endocrine disruptors with putative ... [more ▼]
The assessment of rodent mammary gland morphology is largely used to study the molecular mechanisms driving breast development and to analyze the impact of various endocrine disruptors with putative pathological implications. In this work, we propose a methodology relying on fully automated digital image analysis methods including image processing and quantification of the whole ductal tree and of the terminal end buds (TEB) as well. It allows to accurately and objectively measure both growth parameters and fine morphological glandular structures. Mammary gland elongation was characterized by two parameters: the length and the epithelial area of the ductal tree. Ductal tree fine structures were characterized by: 1) branch end-point density, 2) branching density and 3) branch length distribution. The proposed methodology was compared to quantification methods classically used in the literature. This procedure can be transposed to several software and thus largely used by scientists studying rodent mammary gland morphology. [less ▲]Detailed reference viewed: 26 (1 ULg)
An Improved Molecular Histology Method for Ion Suppression Monitoring and Quantification of Phosphatidyl Cholines During MALDI MSI Lipidomics Analyses.
Jadoul, Laure ; Smargiasso, Nicolas ; et al
in OMICS : A Journal of Integrative Biology (2016), 20(2), 110-21
Tissue lipidomics is one of the latest omics approaches for biomarker discovery in pharmacology, pathology, and the life sciences at large. In this context, matrix-assisted laser desorption/ionization ... [more ▼]
Tissue lipidomics is one of the latest omics approaches for biomarker discovery in pharmacology, pathology, and the life sciences at large. In this context, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is the most versatile tool to map compounds within tissue sections. However, ion suppression events occurring during MALDI MSI analyses make it impossible to use this method for quantitative investigations without additional validation steps. This is especially true for lipidomics, since different lipid classes are responsible for important ion suppression events. We propose here an improved lipidomics method to assess local ion suppression of phospatidylcholines in tissues. Serial tissue sections were spiked with different amounts of PC(16:0 d31/18:1) using a nebulization device. Settings for standard nebulization were strictly controlled for a detection similar to when using spiked tissue homogenates. The sections were simultaneously analyzed by MALDI MSI using a Fourier transform ion cyclotron resonance analyzer. Such a spray-based approach allows taking into account the biochemical heterogeneity of the tissue for the detection of PC(16:0 d31/18:1). Thus, here we present the perspective to use this method for quantification purposes. The linear regression lines are considered as calibration curves and we calculate PC(16:0/18:1) quantification values for different ROIs. Although those values need to be validated by a using a different independent approach, the workflow offers an insight into new quantitative mass spectrometry imaging (q-MSI) methods. This approach of ion suppression monitoring of phosphocholines in tissues may be highly interesting for a large range of applications in MALDI MSI, particularly for pathology using translational science workflows. [less ▲]Detailed reference viewed: 86 (6 ULg)
: Regulation of Tissue Factor by Epithelial-to-Mesenchymal Transitions: Impacts for the metastatic progression.
Francart, Marie-Emilie ; Bourcy, Morgane ; Lambert, Justine et al
Poster (2015, December 03)Detailed reference viewed: 11 (1 ULg)
MT4-MMP, a potential prognostic factor in triple negative breast cancer
Yip, Cassandre ; FOIDART, Pierre ; SOMJA, Joan et al
Scientific conference (2015, December 03)Detailed reference viewed: 25 (9 ULg)
FROM METABOLOMICS STUDY OF AGE RELATED MACULAR DEGENERATION (AMD) TO THE DEVELOPMENT OF NEW PDK INHIBITORS
Arslan, Deniz ; Schoumacher, Matthieu ; Pirotte, Bernard et al
in Arslan, Deniz (Ed.) Gazi Pharma Symposium Abstract Book (2015, November 12)
Metabolomics is one of the most recent technologies in the Omics sciences defined as “the comprehensive characterization of small molecules (called metabolites) in different biological samples.” This ... [more ▼]
Metabolomics is one of the most recent technologies in the Omics sciences defined as “the comprehensive characterization of small molecules (called metabolites) in different biological samples.” This methodology can be applied in many areas, such as biomarker discovery, clinical studies, drug efficacy and toxicity evaluation, diagnostic tools, quality control or drug discovery. Its capability to extract biochemical information associated with a cellular or biological system makes this technique a powerful tool for Medicinal Chemistry. In this work, we present a 1H NMR metabolomics study applied to therapeutic target discovery. Age-related macular degeneration (AMD) is a leading cause of blindness in the elderly population of industrialized countries. This blindness results from the deterioration of the macula, a small part of the retina specialized for the high-acuity vision. Exudative AMD, called “wet”, is characterized by the formation of new blood vessels growing under the retina according to a process named choroidal neovascularization (CNV). Currently, the aetiology and pathogenesis of AMD remain unclear. Nevertheless, a recent metabolomics study performed on the serum of “wet” AMD patients and on a CNV murine model, that mimics the effect of “wet” AMD, have demonstrated that lactate level is clearly involved in the severity of the pathology as well as the relationship between lactate, CNV and AMD. According to this result, we suggest a new therapeutic approach of AMD based on the normalization of blood lactate level. The modulation of the lactate plasma concentration by treatment of the animals with synthetic compounds and more specifically Pyruvate Dehydrogenase Kinase (PDK) inhibitors significantly decrease the CNV. Starting from these results, development of new PDK inhibitors could open the way to innovative treatment opportunities in AMD disease. [less ▲]Detailed reference viewed: 61 (7 ULg)
Dynamics of Internalization and Recycling of the pro-Metastatic Membrane Type 4-Matrix Metalloproteinase (MT4-MMP) in Breast Cancer cells
Truong, Alice ; Yip, Cassandre ; PAYE, Alexandra et al
Poster (2015, October 26)
MT4-MMP (MMP17) is a glycosyl-phosphatidyl inositol-anchored membrane-type matrix metalloproteinase expressed at the cell surface of human breast cancer cells. In triple negative breast cancer, MT4-MMP ... [more ▼]
MT4-MMP (MMP17) is a glycosyl-phosphatidyl inositol-anchored membrane-type matrix metalloproteinase expressed at the cell surface of human breast cancer cells. In triple negative breast cancer, MT4-MMP promotes primary tumor growth and lung metastases. Recently, we demonstrated that EGFR activation and signaling are enhanced by MT4-MMP in a non-proteolytic dependent manner. While trafficking and internalization of EGFR was extensively investigated, little is known about MT4-MMP. Here, we investigated the dimerization, internalization and recycling dynamics of MT4-MMP and its mutated inactive form MT4-MMP-E249A. We demonstrate that MT4-MMP forms dimers and oligomers at the cell surface, a process that was not inhibited neither by broad-spectrum MMP inhibitors (GM6001 and BB94) nor TIMP-2. MT4-MMP is internalized in early endosomes from 10 minutes to 60 minutes. Once internalized, some amount of MT4-MMP is auto-degraded, whereas its inert form E249A was found intact. Large part of the internalized enzyme was recycled intact at the cell surface. By exploring its endocytosis, we found that MT4-MMP is internalized by the CLIC/GEEC pathway, a mechanism that differs from other MT-MMP members. Overall, we provided a new mechanistic insight on the regulatory mechanisms of MT4-MMP in human breast cancer cells. We also, highlighted unique features of MT4-MMP among membrane-associated MMPs, which may be useful for the design of novel therapeutic strategies for metastatic breast cancer. [less ▲]Detailed reference viewed: 32 (19 ULg)
Epithelial-Mesenchymal Transitions induce Tissue Factor expression and pro-coagulant properties, supporting early metastasis of Circulating Tumor Cells.
Bourcy, Morgane ; ; Francart, Marie-Emilie et al
Conference (2015, October)Detailed reference viewed: 19 (7 ULg)
Implication of adamalysin proteases in mesothelioma
Sepult, Christelle ; Rocks, Natacha ; et al
Conference (2015, September 30)Detailed reference viewed: 17 (4 ULg)
Clinical significance of MT4-MMP and EGFR expression in Breast Cancer
Yip, Cassandre ; PAYE, Alexandra ; Truong, Alice et al
Scientific conference (2015, September 11)Detailed reference viewed: 14 (5 ULg)
Involvement of adamalysin proteases in modulations of tumor microenvironment and premetastatic niches.
Donati, Kim ; ; Sepult, Christelle et al
Poster (2015, September)Detailed reference viewed: 17 (1 ULg)
MT4-MMP, a potential therapeutic target in triple negative breast cancer
Yip, Cassandre ; FOIDART, Pierre ; SOMJA, Joan et al
Poster (2015, September)
MT4-MMP and EGFR axis may have a significant role in patient outcome and response to EGFR targeted therapy. This axis is clinically relevant in TNBC, the most aggressive breast cancer subtype. TNBC are ... [more ▼]
MT4-MMP and EGFR axis may have a significant role in patient outcome and response to EGFR targeted therapy. This axis is clinically relevant in TNBC, the most aggressive breast cancer subtype. TNBC are known to express high level of EGFR and treatment options are limited due to the non response of to the EGFR targeted therapy. Expression levels of MT4-MMP and EGFR in TNBC may be used as prognosis factor for the selection of patient who may respond or not to EGFR targeted therapy. Also, our data shed light and the potential therapeutic option of targeting both MT4-MMP and EGFR in TNBC. [less ▲]Detailed reference viewed: 35 (14 ULg)