Implication of Epithelial-to-Mesenchymal Transitions (EMTs) on the formation of fibrin(ogen)-rich vascular nests for Circulating Tumor Cells (CTCs)
Lambert, Justine ; Bourcy, Morgane ; Francart, Marie-Emilie et al
Poster (2016, May)Detailed reference viewed: 26 (7 ULg)
Neonatal Hypoxic-Ischemic Encephalopathy: a new view of an old problem
Tskitishvili, Ekaterine ; VIELLEVOYE, Renaud ; et al
in Références en Gynécologie Obstétrique (2016), 17(1-1),
Neonatal hypoxic-ischemic encephalopathy (HIE) remains a challenge of perinatal medicine. It is an important cause of long term morbidity, including motor and behavioral deficits, mental retardation ... [more ▼]
Neonatal hypoxic-ischemic encephalopathy (HIE) remains a challenge of perinatal medicine. It is an important cause of long term morbidity, including motor and behavioral deficits, mental retardation, seizures and cerebral palsy, and mortality in newborns. This paper reviews the pathophysiology and current concepts of the management of neonatal HIE as well as the future potential neuroprotective strategies for attenuation of this disease. [less ▲]Detailed reference viewed: 144 (6 ULg)
From Metabolomics Study of Age-Related Macular Degeneration (AMD) to the Development of New Pyruvate Dehydrogenase Kinase Inhibitors (PDK)
Arslan, Deniz ; Schoumacher, Matthieu ; Pirotte, Bernard et al
Poster (2016, May)
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 ... [more ▼]
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. PDK and its four isoforms (PDK1-4) regulate the activity of the pyruvate dehydrogenase complex (PDH), a mitochondrial enzyme that plays a major role in the metabolic pathway of glucose, by reversible phosphorylation. Starting from these results, development of new PDK inhibitors could open the way to innovative treatment opportunities in AMD disease. Different analogues of (R)-3,3,3-trifluoro-2-hydroxy-2-methylpropanamide (fig.1) have been already synthetized and pharmacological evaluation is currently in progress. According to the results obtained, various pharmacomodulations will be investigated [less ▲]Detailed reference viewed: 77 (22 ULg)
From Metabolomics to Identification of a new therapeutic approach for Age-Related Macular Degeneration (AMD)
Schoumacher, Matthieu ; De Tullio, Pascal ; LAMBERT, Vincent et al
Poster (2016, May)
Age-related macular degeneration (AMD) is the leading cause of vision loss in the western world among people aged 50 or older. 90% of all vision loss due to AMD result from the exudative form, which is ... [more ▼]
Age-related macular degeneration (AMD) is the leading cause of vision loss in the western world among people aged 50 or older. 90% of all vision loss due to AMD result from the exudative form, which is characterized by choroidal neovascularization (CNV). Age-related changes that induce pathologic CNV are incompletely understood and critical issues remain to be addressed. Metabolomics is defined as the comprehensive study of endogenous metabolites changes in various biological systems. This newly emerging “omic” science provides a unique opportunity to correlate variation of the metabolome with pathological occurrence or progression and/or to identify metabolites that are implicated in the disease. We apply a 1H NMR metabolomics approach on sera collected from AMD patient and healthy volunteers and form a mice model of laser-induced CNV which mimics the effect of exudative AMD. After post-processing treatments, the different spectra were analyzed by statistical discriminant methodologies (PCA, ICA, PLS-DA, O-PLS-DA). These approaches allow the differentiation between control and AMD patients and between laser-induced mice and the control mice group. Moreover, the same discriminating spectral zones have been identified in human and mice model, leading to the emergence of different putative biomarkers. Among these markers, lactate emerges as a key metabolite in both settings. Mechanistically, lactate produced locally and by inflammatory cells, plays a critical role in the onset of the inflammatory and angiogenic phases. In mice model of laser-induced CNV, normalization of circulating lactate by dichloroacetate a pyruvate dehydrogenase kinase (PDK) inhibitor, decreases CNV development. Our data support the innovative concept of lactate as a parainflammation- and angio-metabolite associated to AMD and CNV progression. Moreover, control of blood lactate level via inhibition of PDK provides new options for the treatment of exudative AMD. This study demonstrates the ability of metabolomics for drug target discovery and opens new perspectives for AMD treatment and patient follow-up. [less ▲]Detailed reference viewed: 64 (10 ULg)
Impacts of Ionizing Radiation on the Different Compartments of the Tumor Microenvironment
Leroi, Natacha ; LALLEMAND, François ; COUCKE, Philippe et al
in Frontiers in Pharmacology (2016), 7
During the last decade, the initial cancer cell-centered view of tumors has greatly evolved to an integrated vision of tumor biology taking into account the key contribution of the TME. Obviously, the ... [more ▼]
During the last decade, the initial cancer cell-centered view of tumors has greatly evolved to an integrated vision of tumor biology taking into account the key contribution of the TME. Obviously, the different compartments of TME are closely related and contribute not only to tumor progression, but also to its response to treatments. Importantly, the TME evolves over time during the different steps of cancer development and is also affected by different therapeutic modalities. Although, improvements have been achieved regarding RT delivery to the primary tumor, ionizing radiation also target nontumor cells that influence tumor growth and metastatic dissemination. Different approaches have been proposed to overcome the radioresistance of cancer cells. The TME-mediated radioresistance is now the object of researches, which has been elegantly reviewed recently by Barker et al. (2015) and severalarticles pointed out the importance of treatments that modify the TME and likely radiosensitize tumor (Ansiaux et al., 2005; Crokart et al., 2005b; Frérart et al., 2008). However, the impact of anti-cancer treatments on the TME and consequently on the tumor phenotype, response to treatment and metastases, is often neglected. Here we pointed out the impact of RT on the TME. Recent findings emphasize the interest to optimize RT (i.e., dose per fraction) and timing of surgery (Leroi et al., 2015; Surace et al., 2015) in order to prevent metastatic spreading. The future challenge in RT will be to define the most appropriate combinations between RT, and other therapeutic modalities with the optimal sequence and timing of treatments. In this context, investigation of the TME-related acquired resistance will be essential and will provide important innovative data. [less ▲]Detailed reference viewed: 55 (12 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: 48 (20 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: 43 (3 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: 140 (19 ULg)
Metabolomic analyzes of the tumor microenvironment after neoadjuvant radiotherapy implicated in surgery-related metastatic spreading.
Leroi, Natacha ; BLACHER, Silvia ; Lallemand, François et al
Conference (2016, January 30)Detailed reference viewed: 19 (3 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: 37 (7 ULg)
− Evaluation of Z-VAD-FMK as an anti-apoptotic drug to prevent granulosa cells apoptosis and follicle death after ovarian tissue transplantation
Fransolet, Maïté ; NOEL, Laure ; HENRY, Laurie et al
Poster (2016, January 25)Detailed reference viewed: 24 (4 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: 25 (4 ULg)
Epithelial-mesenchymal transition induces tissue factor and pro-coagulant properties supporting early metastasis of circulating tumor cells.
Bourcy, Morgane ; Suarez-Carmona, Meggy ; Lambert, Justine et al
Poster (2016, January)Detailed reference viewed: 23 (4 ULg)
Dysregulated circulating miRNAs in preeclampsia.
Munaut, Carine ; ; Blacher, Silvia et al
in Biomedical Reports (2016), 5(6), 686-692
Preeclampsia (PE) is a pregnancy-related disease with potentially severe consequences with respect to foeto-maternal morbidity and mortality. However, the molecular pathogenesis of PE remains largely ... [more ▼]
Preeclampsia (PE) is a pregnancy-related disease with potentially severe consequences with respect to foeto-maternal morbidity and mortality. However, the molecular pathogenesis of PE remains largely unknown. Recent reports have shown that microRNAs (miRNAs or miRs) may play important roles in the development of PE. Analysing the miRNAs in sera from preeclamptic women may improve our understanding of the pathophysiological mechanisms of the disease. The aim of this retrospective study was to identify whether circulating miRNAs were differentially expressed in PE patients compared with controls. Serum samples from 23 women who developed PE were compared with samples from 44 pregnant controls. Seventeen circulating miRNAs previously described in PE were chosen for evaluation of their expression by reverse transcription quantitative polymerase chain reaction (RT-qPCR). In the maternal serum, the miR-210-3p, miR-210-5p, miR-1233-3p, and miR-574-5p levels were found to be significantly higher in the PE patients than in the controls (P<0.05). Using a logistic regression model, we evaluated the discriminant power of those differentially expressed miRNAs, and the combination of miR-210-5p and miR-574-5p yielded an area under the curve of 0.7223 for discriminating PE patients from the controls. In conclusion, the fact that four circulating miRNAs (miR-210-3p, miR-210-5p, miR-1233-3p, and miR-574-5p) were differentially expressed in the sera of women who developed PE compared with controls confirms the possible pathophysiological role of miRNAs in PE. [less ▲]Detailed reference viewed: 21 (1 ULg)
Accurate Control of 17beta-Estradiol Long-Term Release Increases Reliability and Reproducibility of Preclinical Animal Studies.
Gérard, Céline ; Gallez, Anne ; Dubois, Charline et al
in Journal of Mammary Gland Biology & Neoplasia (2016)
Estrogens are the subject of intensive researches aiming to elucidate their mechanism of action on the various tissues they target and especially on mammary gland and breast cancer. The use of ready-to ... [more ▼]
Estrogens are the subject of intensive researches aiming to elucidate their mechanism of action on the various tissues they target and especially on mammary gland and breast cancer. The use of ready-to-use slow releasing devices to administer steroids, especially estrogens, to small experimental animals remains the method of choice in terms of animal well-being and of safety for both the researcher and the animal. In this study, we evaluated and compared, in vitro and in vivo, the release kinetic of estradiol (E2) over sixty days from two different slow-releasing systems: the matrix pellet (MP) and the reservoir implant (RI). We compared the impact of these systems in three E2-sensitive mouse models : mammary gland development, human MCF7 adenocarcinoma xenograft and mouse melanoma progression. The real amount of E2 that is released from both types of devices could differ from manufacturer specifications due to inadequate release for MP and initial burst effect for RI. Compared to MP, the interindividual variability was reduced with RI thanks to a superior control of the E2 release. Depending on the dose-dependent sensitivity of the physiological or pathological readout studied, this could lead to an improvement of the statistical power of in vivo experiments and thus to a reduction of the required animal number. Altogether, our data draw attention on the importance to adequately select the slow-releasing device that is the most appropriated to a specific experiment to better fulfill the 3Rs rule (Replacement, Reduction, Refinement) related to animal welfare and protection. [less ▲]Detailed reference viewed: 19 (3 ULg)
Diffusion MRI for following tumor modifications after neoadjuvant radiotherapy.
LALLEMAND, François ; Leroi, Natacha ; Bahri, Mohamed Ali et al
in Radiotherapy & Oncology (2016), 119
Neoadjuvant radiotherapy (NeoRT) improves tumor local control and tumor resection in many cancers. The timing between the end of the NeoRT and surgery is driven by the occurrence of side effects or the ... [more ▼]
Neoadjuvant radiotherapy (NeoRT) improves tumor local control and tumor resection in many cancers. The timing between the end of the NeoRT and surgery is driven by the occurrence of side effects or the tumor downsizing. Some studies demonstrated that the timing of surgery and the RT schedule could influence tumor dissemination and subsequently patient overall survival. We demonstrated the impact of NeoRT on metastatic spreading in a Scid mice model. After an irradiation of 2x5gy, we show more metastasis in the lung when the mice are operated at day 4 compared to day 11. 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. [less ▲]Detailed reference viewed: 26 (8 ULg)
Degradomic and yeast 2-hybrid inactive catalytic domain substrate trapping identifies new membrane-type 1 matrix metalloproteinase (MMP14) substrates: CCN3 (Nov) and CCN5 (WISP2).
; ; Sounni, Nor Eddine et al
in Matrix Biology (2016)
Members of the CCN family of matricellular proteins are cytokines linking cells to the extracellular matrix. We report that CCN3 (Nov) and CCN5 (WISP2) are novel substrates of MMP14 (membrane-type 1 ... [more ▼]
Members of the CCN family of matricellular proteins are cytokines linking cells to the extracellular matrix. We report that CCN3 (Nov) and CCN5 (WISP2) are novel substrates of MMP14 (membrane-type 1-matrix metalloproteinase, MT1-MMP) that we identified using MMP14 "inactive catalytic domain capture" (ICDC) as a yeast two-hybrid protease substrate trapping platform in parallel with degradomics mass spectrometry screens for MMP14 substrates. CCN3 and CCN5, previously unknown substrates of MMPs, were biochemically validated as substrates of MMP14 and other MMPs in vitro-CCN5 was processed in the variable region by MMP14 and MMP2, as well as by MMP1, 3, 7, 8, 9 and 15. CCN1, 2 and 3 are proangiogenic factors yet we found novel opposing activity of CCN5 that was potently antiangiogenic in an aortic ring vessel outgrowth model. MMP14, a known regulator of angiogenesis, cleaved CCN5 and abrogated the angiostatic activity. CCN3 was also processed in the variable region by MMP14 and MMP2, and by MMP1, 8 and 9. In addition to the previously reported cleavages of CCN1 and CCN2 by several MMPs we found that MMPs 8, 9, and 1 process CCN1, and MMP8 and MMP9 also process CCN2. Thus, our study reveals additional and pervasive family-wide processing of CCN matricellular proteins/cytokines by MMPs. Furthermore, CCN5 cleavage by proangiogenic MMPs results in removal of an angiogenic brake held by CCN5. This highlights the importance of thorough dissection of MMP substrates that is needed to reveal higher-level control mechanisms beyond type IV collagen and other extracellular matrix protein remodelling in angiogenesis. SUMMARY: We find CCN family member cleavage by MMPs is more pervasive than previously reported and includes CCN3 (Nov) and CCN5 (WISP2). CCN5 is a novel antiangiogenic factor, whose function is abrogated by proangiogenic MMP cleavage. By processing CCN proteins, MMPs regulate cell responses angiogenesis in connective tissues. [less ▲]Detailed reference viewed: 13 (1 ULg)
Tissue factor induced by epithelial-mesenchymal transition triggers a pro-coagulant state that drives metastasis of circulating tumor cells.
Bourcy, Morgane ; Suarez-Carmona, Meggy ; Lambert, Justine et al
in Cancer Research (2016)
Epithelial-mesenchymal transition (EMT) is prominent in circulating tumor cells (CTC), but how it influences metastatic spread in this setting is obscure. Insofar as blood provides a specific ... [more ▼]
Epithelial-mesenchymal transition (EMT) is prominent in circulating tumor cells (CTC), but how it influences metastatic spread in this setting is obscure. Insofar as blood provides a specific microenvironment for tumor cells, we explored a potential link between EMT and coagulation that may provide EMT-positive CTC with enhanced colonizing properties. Here we report that EMT induces tissue factor (TF), a major cell-associated initiator of coagulation and related pro-coagulant properties in the blood. TF blockade by antibody or shRNA diminished the pro-coagulant activity of EMT-positive cells, confirming a functional role for TF in these processes. Silencing the EMT transcription factor ZEB1 inhibited both EMT-associated TF expression and coagulant activity, further strengthening the link between EMT and coagulation. Accordingly, EMT-positive cells exhibited a higher persistance/survival in the lungs of mice colonized after intravenous injection, a feature diminished by TF or ZEB1 silencing. In tumor cells with limited metastatic capability, enforcing expression of the EMT transcription factor Snail increased TF, coagulant properties and early metastasis. Clinically, we identified a subpopulation of CTC expressing vimentin and TF in the blood of metastatic breast cancer patients consistent with our observations. Overall, our findings define a novel EMT-TF regulatory axis which triggers local activation of coagulation pathways to support metastatic colonization of EMT-positive CTC. [less ▲]Detailed reference viewed: 57 (22 ULg)
Impact of estetrol on breast cancer development, metastatic dissemination and angiogenesis
Gallez, Anne ; Gérard, Céline ; Blacher, Silvia et al
The increased risk of breast cancer and thromboembolism in women who take Hormone Replacement Therapy (HRT) currently is a major public health problem. The discovery of novel molecules with better safety ... [more ▼]
The increased risk of breast cancer and thromboembolism in women who take Hormone Replacement Therapy (HRT) currently is a major public health problem. The discovery of novel molecules with better safety profile would provide useful advances for patient care. Estretrol (E4) appears as a promising candidate for HRT. Indeed, in contrast to current treatment containing ethinyl estradiol or estradiol (E2), E4 has a minimal impact on liver cells activity supporting a decreased incidence on thromboembolic events. In preclinical studies, E4 has been effective against the main symptoms of menopause such as hot flushes, vaginal atrophy, and osteoporosis, from a starting dose of 0.3 mg/kg/day. The aim of this study was to define the impact of E4 on breast cancer development when it is used at concentrations effective for menopause symptom relief. Treatment of estrogen receptor (ER)-positive breast cancer-developing mice (MMTV-PyMT) with several concentrations of E4 has shown that 0.3 mg/kg/day E4 did not increase tumor development and metastasis dissemination. However, at 3mg/kg/day, E4 increased the growth of hormone-dependent tumors and their metastatic dissemination in ovariectomized and intact mice. This effect was similar to the one observed with E2 used at 0.08 mg/kg/day. In an in vivo model of ER-negative tumors, we observed that 3mg/kg/day E4 improved tumor growth by increasing angiogenesis, and subsequently decreasing necrosis and tumor hypoxia. In contrast, 0.3 mg/kg/day E4 did not induce any of these effects on ER-negative tumors and tumor microenvironment. In conclusion, we have shown that 0.3 mg/kg/day E4, already reported to prevent menopause symptoms, does not increase breast tumor growth, metastasis dissemination, and angiogenesis. However, similarly to E2, higher concentrations of E4 are pro-tumorous. These results support that E4, if it is used in strictly controlled clinical applications, could have no or only limited impact on breast cancer. [less ▲]Detailed reference viewed: 72 (2 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: 50 (11 ULg)