References of "Pequeux, Christel"
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See detailOzone-primed neutrophils promote early steps of tumor cell metastasis to lungs by enhancing their NET production
Rocks, Natacha ULiege; Vanwinge, Céline ULiege; Radermecker, Coraline ULiege et al

in Thorax (2019), 0

Air pollution, including particulates and gazes such as ozone (O3), is detrimental for patient’s health and has repeatedly been correlated to increased morbidity and mortality in industrialized countries ... [more ▼]

Air pollution, including particulates and gazes such as ozone (O3), is detrimental for patient’s health and has repeatedly been correlated to increased morbidity and mortality in industrialized countries. Although studies have described a link between ambient particulate matter and increased lung cancer morbidity, no direct relation has yet been established between O3 exposure and metastatic dissemination to lungs. [less ▲]

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See detailDevelopment of injectable liposomes and drug-in-cyclodextrin-in-liposome formulations encapsulating estetrol to prevent cerebral ischemia of premature babies.
Palazzo, Claudio; Laloy, Julie; Delvigne, Anne Sophie et al

in European Journal of Pharmaceutical Sciences (2019), 9(127), 52-59

Neonatal Hypoxic-Ischemic Encephalopathy (HIE), a brain disease due to brain hypoxia along with ischemia and reduced cerebral blood flow, is one of the primary reasons of severe injury among babies ... [more ▼]

Neonatal Hypoxic-Ischemic Encephalopathy (HIE), a brain disease due to brain hypoxia along with ischemia and reduced cerebral blood flow, is one of the primary reasons of severe injury among babies prematurely born. No efficacy treatment is available to the present day. Estetrol (E4), a major estradiol metabolite, has an important role in the brain development and protection. The aim of this study is to develop new injectable liposome and drug-in-cyclodextrin-in-liposome (DCL) formulations, encapsulating E4 in order to enhance its crossing through the blood-brain barrier (BBB). Liposome and DCL formulations were prepared and were physiochemically characterized. Stability in foetal bovine serum (FBS) was evaluated. LDH and MTS tests on endothelial, neuronal and BBB model cells, as well as hemocompatibility of the nanovectors were performed in vitro. In vitro BBB passage was evaluated using human BBB cell line (hCMEC/D3). All the formulations had average particle size below 150 nm, polydispersity index below 0.10 and ζ potential around + 30 mV. The encapsulation efficacy for liposomes was between 3% and 10% while those of DCL are between 15% and 35%. The effect of liposome and DCL formulations on cell viability and integrity was evaluated. The results showed no toxic effects on all the tested cell lines. Hemocompatibility tests showed no hemolysis, platelet aggregation or effects on coagulation, confirming the possibility of the formulations to be intravenously administrated. BBB passage tests highlighted the capability of the formulations to pass the BBB and reach the brain. Therefore, the formulations are promising drug delivery system to target estrogens to the brain, due to their physiochemical characteristics. [less ▲]

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See detailLymph/angiogenesis contributes to sex differences in lung cancer through oestrogen receptor alpha signalling
Dubois, Charline; Rocks, Natacha ULiege; Blacher, Silvia ULiege et al

in Endocrine-Related Cancer (2019), 26(2), 201-216

Oestrogen signalling pathways are emerging targets for lung cancer therapy. Unravelling the contribution of oestrogens in lung cancer development is a pre-requisite to support the development of sex-based ... [more ▼]

Oestrogen signalling pathways are emerging targets for lung cancer therapy. Unravelling the contribution of oestrogens in lung cancer development is a pre-requisite to support the development of sex-based treatments and identify patients who could potentially benefit from anti-oestrogen treatments. In this study, we highlight the contribution of lymphatic and blood endothelia in the sex-dependent modulation of lung cancer. The orthotopic graft of syngeneic lung cancer cells into immunocompetent mice showed that lung tumours grow faster in female mice than in males. Moreover, oestradiol (E2) promoted tumour development, increased lymph/angiogenesis and VEGFA and bFGF levels in lung tumours of females through an oestrogen receptor (ER) alpha-dependent pathway. Furthermore, while treatment with ERb antagonist was inefficient, ERa antagonist (MPP) and tamoxifen decreased lung tumour volumes, altered blood and lymphatic vasculature and reduced VEGFA and bFGF levels in females, but not in males. Finally, the quantification of lymphatic and blood vasculature of lung adenocarcinoma biopsies from patients aged between 35 and 55 years revealed more extensive lymphangiogenesis and angiogenesis in tumour samples issued from women than from men. In conclusion, our findings highlight an E2/ERa-dependent modulation of lymphatic and blood vascular components of lung tumour microenvironment. Our study has potential clinical implication in a personalised medicine perspective by pointing to the importance of oestrogen status or supplementation on lung cancer development that should be considered to adapt therapeutic strategies. [less ▲]

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See detailEstetrol, a newly designated orphan drug, for attenuation of neonatal Hypoxic-Ischemic Encephalopathy (HIE)
Tskitishvili, Ekaterine ULiege; Pequeux, Christel ULiege; VIELLEVOYE, Renaud ULiege et al

Poster (2018, November 13)

Estetrol, a newly designated orphan drug, for attenuation of neonatal Hypoxic-Ischemic Encephalopathy (HIE) Ekaterine Tskitishvili1*, Christel Pequeux1, Renaud Viellevoye2, Michelle Nisolle3, Agnes Noël1 ... [more ▼]

Estetrol, a newly designated orphan drug, for attenuation of neonatal Hypoxic-Ischemic Encephalopathy (HIE) Ekaterine Tskitishvili1*, Christel Pequeux1, Renaud Viellevoye2, Michelle Nisolle3, Agnes Noël1 and Jean-Michel Foidart1 1Laboratory of Development Biology and Tumor, University of Liege, Liege, Belgium; 2Department of Pediatrics, University of Liege, Liege, Belgium; 3Department of Ob/Gyn, University of Liege, Liege, Belgium Estetrol (E4) is a fetal estrogen synthesized only during human pregnancy. We aimed to study its role in attenuation of neonatal HIE. In vitro we defined antioxidative and cell viability effects of E4 on primary hippocampal cell cultures in oxidative stress condition by using lactate dehydrogenase (LDH) activity and cell survival (MTS) assays. To study the neuroprotective and therapeutic effects of E4 in vivo neonatal HIE model of 7-day-old newborn rat pups was used. Brains were studied at the level of the hippocampus and cortex. Intact cell counting and expressions of markers for gray and white matter (MAP-2 and MBP), neurogenesis (DCX) and angiogenesis (VEGF) were evaluated by histo- and immunohistochemistry. The serum levels of brain damage markers (S100B and GFAP) were measured by ELISA. Our results demonstrate that E4 has significant antioxidative and cell survival properties along with neuroprotective and therapeutic effects. It decreases the early gray and white matter loss and promotes neuro- and angiogenesis in vivo. Combined use of E4 with other steroids does not have priority over the single use of E4. We also defined that E4's antioxidative actions mostly depend on ERα and ERβ, whereas neurogenesis and possibly promyelinating activities might be realized through ERβ. Treatment by E4 has no effects on body weight, brain weight or body temperature. E4 might become an important safe and physiological substance to treat neonatal HIE. Based on our data EMA granted orphan drug designation to E4. References 1.Tskitishvili E, Nisolle M, Munaut C, Pequeux C, Gerard C, Noel A, Foidart JM.Estetrol attenuates Neonatal Hypoxic-Ischemic brain injury. Exp Neurol 2014; 261:298-307. 2. Tskitishvili E , Pequeux C, Munaut C, Viellevoye R, Nisolle M, Noel A, Foidart JM. Use of Estetrol with other Steroids for Attenuation of Neonatal Hypoxic-Ischemic brain injury: to combine or not to combine? Oncotarget 2016; 7(23):33722-43. 3. Tskitishvili E,Viellevoye R, Gerard C, Pequeux C, Munaut C, Nisolle M, Noel A, Foidart JM. Neonatal Hypoxic-Ischemic Encephalopathy: a new view of an old problem. Références en Gynécologie Obstetrique. 2016 17;1-4 4. Tskitishvili E, Pequeux C, Munaut C, Viellevoye R, Nisolle M, Noël A, Foidart JM. Estrogen receptors and estetrol-dependent neuroprotective actions: a pilot study. J Endocrinol. 2017; 232(1):85-95. 5.Foidart JM, Tskitishvili E. International patent application. Estrogenic components for use in the treatment of neurological disorders. [less ▲]

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See detailInclusion of 17β-estradiol into liposome prevent the activation of membrane initiated signaling of ERalpha
Gallez, Anne ULiege; Palazzo, Claudio; Evrard, Brigitte ULiege et al

Poster (2018)

Estrogens are implicated in many physiological and pathological processes thanks to their interaction with estrogen receptors (ERs). The estrogen receptor alpha (ERα) controls reproduction, normal mammary ... [more ▼]

Estrogens are implicated in many physiological and pathological processes thanks to their interaction with estrogen receptors (ERs). The estrogen receptor alpha (ERα) controls reproduction, normal mammary gland development and breast cancer progression. The activation of ERα by estrogens, especially by 17β-estradiol (E2), leads to two major pathways: (1) the genomic effects associated to the transcriptional activity of the ERα and (2) the MISS (Membrane Initiated Steroid Signaling) effects related to the induction of fast signaling pathways occurring when ERα is anchored to the plasma membrane. Liposome are small non-toxic and biodegradable vectors widely studied for treatment of pathologies, like multiple sclerosis, Parkinson and Alzheimer disease and cancer. The encapsulation of several types of molecules (proteins, DNA and steroids), the protection of the activity and the improvement of the pharmacokinetic properties of these compounds represent the main advantages of liposome’s use. However, the impact of the encapsulation on molecular mechanisms is not yet established. As a proof of concept, we evaluate the impact of E2 inclusion into liposome (named POPC E2) in vitro and in vivo on ERα signaling pathway activation. [less ▲]

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See detailERα- and dose-dependent effect of estetrol on angiogenesis and tumor growth
Gallez, Anne ULiege; BLACHER, Silvia ULiege; Gérard, Céline et al

Poster (2017, November 07)

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See detailESTROGEN RECEPTORS AND ESTETROL-DEPENDENT NEUROPROTECTIVE ACTIONS: A PILOT STUDY
Tskitishvili, Ekaterine ULiege; Pequeux, Christel ULiege; Munaut, Carine ULiege et al

Conference (2017, October 20)

Context: Estetrol (E4) has strong antioxidative, neurogenic and angiogenic effects in neural system resulting in the attenuation of neonatal hypoxic–ischemic encephalopathy. Objective: We aimed to define ... [more ▼]

Context: Estetrol (E4) has strong antioxidative, neurogenic and angiogenic effects in neural system resulting in the attenuation of neonatal hypoxic–ischemic encephalopathy. Objective: We aimed to define the role of estrogen receptors in E4-dependent actions in neuronal cell cultures and prove the promyelinating effect of E4. Methods: In vitro the antioxidative and cell survival/proliferating effects of E4 on H2O2-induced oxidative stress in primary hippocampal cell cultures were studied using different combinations of specific inhibitors for ERα (MPP dihydrochloride), ERβ (PHTTP), GPR30 (G15) and palmytoilation (2-BR). LDH activity and cell survival assays were performed. In vivo the promyelinating role of different concentrations of E4 (1 mg/kg/day, 5 mg/kg/day, 10 mg/kg/day, 50 mg/kg/day) was investigated using the hypoxic–ischemic brain damage model in the 7-day-old immature rats before/after the induction of hypoxic–ischemic insult. Myelin basic protein (MBP) immunostaining was performed on brain coronal sections. Results: Our results show that LDH activity is significantly upregulated in cell cultures where the E4’s effect was completely blocked by concomitant treatment either with ERα and ERβ inhibitors (MPP and PHTPP, respectively), or ERα and ERβ inhibitors combined with 2-BR. Cell survival is significantly downregulated in cell cultures where the effect of E4 was blocked by ERβ inhibitor (PHTTP) alone. The blockage of GRP30 receptor did affect neither LDH activity nor cell survival. MBP immunostaining is significantly upregulated in E4-pretreated groups at a concentration of 5 mg/kg/day and 50 mg/kg/day E4, whereas the MBP-positive area OD ratio is significantly increased in all the E4-treated groups. Conclusions: E4’s antioxidative actions mostly depend on ERα and ERβ, whereas neurogenesis and possibly promyelinating activities might be realized through ERβ. [less ▲]

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See detailWhole blood microsampling for the quantitation of estetrol without derivatization by liquid chromatography-tandem mass spectrometry
Nys, Gwenaël ULiege; Gallez, Anne ULiege; Kok, Miranda ULiege et al

in Journal of Pharmaceutical and Biomedical Analysis (2017), 140

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See detailDose-Dependant effect of Estetrol on Angiogenesis and Tumor growth
Gallez, Anne ULiege; BLACHER, Silvia ULiege; Lenfant, Françoise et al

Conference (2017, May 19)

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See detailDose-dependent effect of Estetrol on Angiogenesis and Tumor Growth
Gallez, Anne ULiege; Blacher, Silvia ULiege; Lenfant, Françoise et al

Poster (2017, April 24)

Hormone replacement therapies (HRT) based on estrogen preparations are the most powerful treatments to prevent menopause symptoms. However, they are associated to an increased risk of breast cancer and ... [more ▼]

Hormone replacement therapies (HRT) based on estrogen preparations are the most powerful treatments to prevent menopause symptoms. However, they are associated to an increased risk of breast cancer and they sustain the development of Estrogen Receptor α-positive tumors (ERα+). In addition, we have previously observed that estradiol (E2) can promote the growth of ERα-negative (ERα-) tumors, by increasing tumor angiogenesis that subsequently improves oxygen and nutrients delivery, thereby preventing hypoxia and necrosis. To identify new and safe drugs for the development of HRT presenting a better benefit/risk ratio, it is therefore necessary to evaluate the potential impact of new candidates on both ERα+ and ERα- tumors. In this context, estetrol (E4), a natural estrogen exclusively produced by the fetal liver, is a promising candidate. [less ▲]

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See detailCancer associated fibroblast-derived integrin α11 regulates PDGFRβ signaling to promote breast cancer progression
Primac, Irina ULiege; Blacher, Silvia ULiege; cimino, Jonathan et al

Conference (2017, April 24)

CAF-specific proteins can provide important prognostic markers and targets for anticancer drugs. Recently, integrin α11 (ITGA11) emerged as a new biomarker of CAFs. ITGA11 is mainly expressed by ... [more ▼]

CAF-specific proteins can provide important prognostic markers and targets for anticancer drugs. Recently, integrin α11 (ITGA11) emerged as a new biomarker of CAFs. ITGA11 is mainly expressed by mesenchymal cells and is correlated with fibroblast activation and matrix reorganization. While the role of ITGA11 in wound healing has been well described, only a very limited number of reports have assessed its role in the cancer disease. This research project aims to investigate the role of stromal ITGA11 in breast cancer. To analyze the in vivo effects of ITGA11 on tumor insurgence, growth and metastasis, we crossed the oncogenic MMTv-PyMT mice with the ITGA11 KO/WT mice, which develop spontaneously breast tumors. ITGA11 deletion strongly delayed tumor growth and metastasis in PyMT mouse model. ITGA11 was poorly expressed at early stages of the tumor progression and its expression was strongly increased in the late stage invasive carcinomas. Importantly, a reduced angiogenesis and collagen content was observed in tumors lacking of ITGA11. Furthermore, a strong co-localization between ITGA11 and PDGFRb, but not other CAF markers such as alpha smooth actin, was also observed within the tumor stroma, suggesting that ITGA11 defines a subpopulation of CAFs, which is not represented by myofibroblasts, but rather PDGFRb+ CAFs. For mechanistic investigation, CAFs and breast cancer cells were isolated from the PyMT model. ITGA11 co-immunoprecipitated with PDGFRb in the isolated CAFs and regulated its phosphorylation. Interestingly, ITGA11-deficient CAFs failed to promote CAF and cancer cell invasion, in contrast to WT CAFs in a spheroid invasion assay. A high throughput comparative proteomics analysis on CAF spheroids in 3D a system was next performed. Proteomics data identified several proteins with relevance in the cancer disease which were significantly modulated in CAFs through ITGA11 down-regulation. The top-ranking candidates are under validation and molecular pathways, which may link these targets and ITGA11 will be further analyzed in the in vitro models. Overall, these in vivo and in vitro data show that ITGA11 defines a PDGFRβ+ subpopulation of CAFs distinct from α-SMA+ myofibroblasts that promote tumor cell invasion and angiogenesis at late stages of carcinoma evolution. ITGA11 is a promising target within the stroma of breast cancer and further investigations of its molecular signaling pathways will be of great relevance. [less ▲]

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See detailLc-chip versus UHPLC-tandem mass spectrometry for the quantitation of estetrol and estradiol without derivatization after whole blood microsampling
Nys, Gwenaël ULiege; Servais, Anne-Catherine ULiege; Pequeux, Christel ULiege et al

Conference (2017, March 29)

the aim of this work was to conduct a PK study on mice to select the most appropriate administration route for E2 and E4 formulations. To achieve this goal, a reference method for the quantitation of both ... [more ▼]

the aim of this work was to conduct a PK study on mice to select the most appropriate administration route for E2 and E4 formulations. To achieve this goal, a reference method for the quantitation of both estrogens after whole blood microsampling was developed and validated on a UHPLC-MS/MS system. This reference method was later transferred on LC-chip device and both methods were compared in terms of analytical parameters such as response function, accuracy, precision, trueness and limit of quantification. [less ▲]

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See detailAccurate Control of 17beta-Estradiol Long-Term Release Increases Reliability and Reproducibility of Preclinical Animal Studies.
Gérard, Céline ULiege; Gallez, Anne ULiege; Dubois, Charline ULiege et al

in Journal of Mammary Gland Biology and Neoplasia (2017), 22(1), 1-11

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 ▲]

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See detailEstrogen receptors and estetroldependent neuroprotective actions: a pilot study
Tskitishvili, Ekaterine ULiege; Pequeux, Christel ULiege; Munaut, Carine ULiege et al

in Journal of Endocrinology (2017), 232(1), 85-95

Estetrol (E4) has strong antioxidative, neurogenic and angiogenic effects in neural system resulting in the attenuation of neonatal hypoxic-ischemic encephalopathy. We aimed to define the role of estrogen ... [more ▼]

Estetrol (E4) has strong antioxidative, neurogenic and angiogenic effects in neural system resulting in the attenuation of neonatal hypoxic-ischemic encephalopathy. We aimed to define the role of estrogen receptors in E4-dependent actions in neuronal cell cultures and prove the promyelinating effect of E4. In vitro the antioxidative and cell survival/proliferating effects of E4 on H2O2-induced oxidative stress in primary hippocampal cell cultures were studied using different combinations of specific inhibitors for ERalpha (MPP dihydrochloride), ERbeta (PHTTP), GPR30 (G15) and palmytoilation (2-BR). LDH activity and cell survival assays were performed. In vivo the promyelinating role of different concentrations of E4 (1 mg/kg/day, 5 mg/kg/day, 10 mg/kg/day, 50 mg/kg/day) was investigated using the hypoxic-ischemic brain damage model in the 7-day-old immature rats before/after the induction of hypoxic-ischemic insult. Myelin basic protein (MBP) immunostaining was performed on brain coronal sections. Our results show that LDH activity is significantly upregulated in cell cultures where the E4's effect was completely blocked by concomitant treatment either with ERalpha and ERbeta inhibitors (MPP and PHTPP, respectively), or ERalpha and ERbeta inhibitors combined with 2-BR. Cell survival is significantly downregulated in cell cultures where the effect of E4 was blocked by ERbeta inhibitor (PHTTP) alone. The blockage of GRP30 receptor did affect neither LDH activity nor cell survival. MBP immunostaining is significantly upregulated in E4-pretreated groups at a concentration of 5 mg/kg/day and 50 mg/kg/day E4, whereas the MBP-positive area OD ratio is significantly increased in all the E4-treated groups. E4's antioxidative actions mostly depend on ERalpha and ERbeta, whereas neurogenesis and possibly promyelinating activities might be realized through ERbeta. [less ▲]

Detailed reference viewed: 75 (24 ULiège)