Estetrol is a weak estrogen antagonizing estradiol-dependent mammary gland proliferation.
Gérard, Céline ; Blacher, Silvia ; et al
in Journal of Endocrinology (2015), 224(1), 86-95
Estetrol (E4) is a natural estrogen produced exclusively by the human fetal liver during pregnancy. Its physiological activity remains unknown. In contrast to ethinyl estradiol (EE) and estradiol (E2), E4 ... [more ▼]
Estetrol (E4) is a natural estrogen produced exclusively by the human fetal liver during pregnancy. Its physiological activity remains unknown. In contrast to ethinyl estradiol (EE) and estradiol (E2), E4 has a minimal impact on liver cells activity and could provide a better safety profile in contraception or hormone therapy. The aim of this study was to delineate if E4 exhibits an activity profile distinct from that of E2 on mammary gland. Compared to E2, E4 acted as a low affinity estrogen in both, human in vitro and murine in vivo, models. E4 was 100 times less potent than E2 to stimulate the proliferation of human breast epithelial (HBE) cells and murine mammary gland in vitro and in vivo, respectively. This effect was prevented by fulvestrant and by tamoxifen supporting the notion that ERalpha is the main mediator of the estrogenic effect of E4 on the breast. Interestingly, when E4 was administered along with E2, it significantly antagonized the strong stimulatory effect of E2 on HBE cells proliferation and on the growth of mammary ducts. This study characterizes for the first time the impact of E4 on mammary gland. Our results highlight that E4 is less potent than E2 and exhibits antagonistic properties towards the proliferative effect of E2 on breast epithelial cells. These data support E4 as a potential new estrogen for clinical use with a reduced impact on breast proliferation. [less ▲]Detailed reference viewed: 32 (13 ULg)
Soluble factors regulated by epithelial-mesenchymal transition mediate tumour angiogenesis and myeloid cell recruitment.
Suarez-Carmona, Meggy ; Bourcy, Morgane ; et al
in Journal of Pathology (The) (2015)
Epithelial-to-mesenchymal transition (EMT) programs provide cancer cells with invasive and survival capacities that might favor metastatic dissemination. Whilst signaling cascades triggering EMT have been ... [more ▼]
Epithelial-to-mesenchymal transition (EMT) programs provide cancer cells with invasive and survival capacities that might favor metastatic dissemination. Whilst signaling cascades triggering EMT have been extensively studied, the impact of EMT on the crosstalk between tumor cells and the tumor microenvironment remains elusive. We aimed to identify EMT-regulated soluble factors that facilitate the recruitment of host cells in the tumor. Our findings indicate that EMT phenotypes relate to the induction of a panel of secreted mediators, namely IL-8, IL-6, sICAM-1, PAI-1 and GM-CSF, and implicate the EMT-transcription factor Snail as a regulator of this process. We further show that EMT-derived soluble factors are pro-angiogenic in vivo (in the mouse ear sponge assay), ex vivo (in the rat aortic ring assay) and in vitro (in a chemotaxis assay). Additionally, conditioned medium from EMT-positive cells stimulates the recruitment of myeloid cells. In a bank of 40 triple-negative breast cancers, tumors presenting features of EMT were significantly more angiogenic and infiltrated by a higher quantity of myeloid cells compared to tumors with little or no EMT. Taken together, our results show that EMT programs trigger the expression of soluble mediators in cancer cells that stimulate angiogenesis and recruit myeloid cells in vivo, which might in turn favor cancer spread. [less ▲]Detailed reference viewed: 26 (11 ULg)
Influence of mouse strain on ovarian tissue recovery after engraftment with angiogenic factor.
Fransolet, Maïté ; Henry, Laurie ; et al
in Journal of Ovarian Research (2015), 8(1), 14
BACKGROUND: For women facing gonadotoxic treatment, cryopreservation of ovarian tissue with subsequent retransplantation during remission is a promising technique for fertility preservation. However ... [more ▼]
BACKGROUND: For women facing gonadotoxic treatment, cryopreservation of ovarian tissue with subsequent retransplantation during remission is a promising technique for fertility preservation. However, follicle loss within grafted ovarian tissue can be caused by ischemia and progressive revascularization. Several xenograft models using different immunodeficient rodent lines are suitable for studying ovarian tissue survival and follicular viability after frozen-thawed ovarian cortex transplantation. SCID mice, which are deficient for functional B and T cells, are the most commonly used mice for ovarian xenograft studies. However, due to incomplete immunosuppression, NOD-SCID mice displaying low NK cell function and an absence of circulating complement might be more appropriate. The present study aims to define the most appropriate immunodeficient mouse strain for ovarian tissue xenotransplantation by comparing ovarian graft recovery in SCID and NOD-SCID mice following engraftment in the presence of isoform 111 of vascular endothelial growth factor. METHODS: Sheep ovarian cortex fragments were embedded in a collagen matrix, with or without VEGF111, before being stitched onto the ovaries of SCID and NOD-SCID mice. Transplants were recovered after 3 days to study early revascularization or after 3 weeks to evaluate follicle preservation and tissue fibrosis through histological analyses. RESULTS: At day 3, vessels were largely reorganized in the ovarian grafts of both mouse strains. After 3 weeks, the cortical tissue was clearly identifiable in SCID mice but not in NOD-SCID mice. Upon VEGF111 treatment, vascularization was significantly improved 3 days after transplantation in SCID mice. This increase in vessel density was correlated with better follicular preservation in SCID mice 3 weeks after transplantation. Fibrosis was not decreased by VEGF treatment in either mouse strain. CONCLUSIONS: Tissue architecture and follicular morphology were better preserved in ovarian tissues grafted in SCID mice in comparison with NOD-SCID mice. Moreover, tissue revascularization was improved in SCID mice by VEGF111 graft treatment. Thus, we consider SCID mice to be the best murine model for studying ovarian tissue xenografts. [less ▲]Detailed reference viewed: 16 (1 ULg)
Isoform 165 of vascular endothelial growth factor in collagen matrix improves ovine cryopreserved ovarian tissue revascularisation after xenotransplantation in mice.
Henry, Laurie ; LABIED, Soraya ; Fransolet, Maïté et al
in Reproductive biology and endocrinology (2015), 13(1), 15
BACKGROUND: Aggressive anti-cancer treatments can result in ovarian failure. Ovarian cryopreservation has been developed to preserve the fertility of young women, but early graft revascularisation still ... [more ▼]
BACKGROUND: Aggressive anti-cancer treatments can result in ovarian failure. Ovarian cryopreservation has been developed to preserve the fertility of young women, but early graft revascularisation still requires improvement. METHODS: Frozen/thawed sheep ovarian cortical biopsies were embedded in collagen matrix with or without isoform 165 of vascular endothelial growth factor (VEGF165) and transplanted into ovaries of immunodeficient mice. Ovaries were chosen as transplantation sites to more closely resemble clinical conditions in which orthotopic transplantation has previously allowed several spontaneous pregnancies. RESULTS: We found that VEGF165 significantly increased the number of Dextran-FITC positive functional vessels 3 days after grafting. Dextran- fluorescein isothiocyanate (FITC) positive vessels were detectable in 53% and 29% of the mice in the VEGF-treated and control groups, respectively. Among these positive fragments, 50% in the treated group displayed mature smooth-muscle-actin-alpha (alpha-SMA) positive functional vessels compared with 0% in the control group. CD31 positive murine blood vessels were observed in 40% of the VEGF165 transplants compared with 21% of the controls. After 3 weeks, the density of murine vessels was significantly higher in the VEGF165 group. CONCLUSION: The encapsulation of ovarian tissue in collagen matrix in the presence of VEGF165 before grafting has a positive effect on functional blood vessel recruitment. It can be considered as a useful technique to be improved and further developed before human clinical applications in female cancer patients in the context of fertility preservation. [less ▲]Detailed reference viewed: 17 (0 ULg)
EGFR activation and signaling in cancer cells are enhanced by the membrane-bound metalloprotease MT4-MMP.
Paye, Alexandra ; Truong, Alice ; Yip, Cassandre et al
in Cancer Research (2014), 74(23), 6758-70
MT4-MMP (MMP-17) is a GPI-anchored matrix metalloprotease expressed on the surface of cancer cells which promotes tumor growth and metastasis. In this report, we identify MT4-MMP as an important driver of ... [more ▼]
MT4-MMP (MMP-17) is a GPI-anchored matrix metalloprotease expressed on the surface of cancer cells which promotes tumor growth and metastasis. In this report, we identify MT4-MMP as an important driver of cancer cell proliferation through CDK4 activation and retinoblastoma protein (Rb) inactivation. We also determine a functional link between MT4-MMP and the growth factor receptor EGFR. Mechanistic experiments revealed direct association of MT4-MMP and its positive effects on EGFR phosphorylation in response to TGF- and EGF in cancer cells. Notably, the effects of MT4-MMP on proliferation and EGFR activation did not rely on metalloprotease activity. Clinically, MT4-MMP and EGFR expression were correlated in human triple negative breast cancer specimens. Altogether our results identify MT4-MMP as a positive modifier of EGFR outside-in signaling that acts to cooperatively drive cancer cell proliferation. [less ▲]Detailed reference viewed: 51 (12 ULg)
Does neoadjuvant radiotherapy and the timing of surgery modify metastatic dissemination?
Leroi, Natacha ; BLACHER, Silvia ; Marée, Raphaël et al
Conference (2014, June 29)Detailed reference viewed: 17 (4 ULg)
DUSP3/VHR is a pro-angiogenic atypical dual-specificity phosphatase
Amand, Mathieu ; Erpicum, Charlotte ; BAJOU, Khalid et al
Poster (2014, January 27)Detailed reference viewed: 47 (19 ULg)
X-ray microtomography: A new tool to follow soft material shrinkage during convective drying
Léonard, Angélique ; Blacher, Silvia ; Marchot, Pierre et al
in 2nd World Congress on Industrial Process Tomography : Hannover, Germany 29-31 août 2001 (2014)
X-ray microtomography is proposed as a new tool to investigate the shrinkage of soft material which occurs during convective drying. Reliable shrinkage curves are obtained with samples of wastewater ... [more ▼]
X-ray microtomography is proposed as a new tool to investigate the shrinkage of soft material which occurs during convective drying. Reliable shrinkage curves are obtained with samples of wastewater treatment sludge. We develop a four zones model to describe the drying kinetics based of the experimental data provided by X-ray microtomography. The observation of the drying and shrinkage curves allows us to determine 3 critical water content values, which define different drying zones where extragranular, intragranular or mixed limitations prevail. When drying is externally controlled, the decrease of the drying rate observed during experiments can be related to the reduction of the external area of the sample. © 2014 International Society for Industrial Process Tomography. [less ▲]Detailed reference viewed: 8 (1 ULg)
DUSP3/VHR is a pro-angiogenic atypical dual-specificity phosphatase
Amand, Mathieu ; Erpicum, Charlotte ; BAJOU, Khalid et al
in Molecular Cancer (2014)
Background DUSP3 phosphatase, also known as Vaccinia-H1 Related (VHR) phosphatase, encoded by DUSP3/Dusp3 gene, is a relatively small member of the dual-specificity protein phosphatases. In vitro studies ... [more ▼]
Background DUSP3 phosphatase, also known as Vaccinia-H1 Related (VHR) phosphatase, encoded by DUSP3/Dusp3 gene, is a relatively small member of the dual-specificity protein phosphatases. In vitro studies showed that DUSP3 is a negative regulator of ERK and JNK pathways in several cell lines. On the other hand, DUSP3 is implicated in human cancer. It has been alternatively described as having tumor suppressive and oncogenic properties. Thus, the available data suggest that DUSP3 plays complex and contradictory roles in tumorigenesis that could be cell type-dependent. Since most of these studies were performed using recombinant proteins or in cell-transfection based assays, the physiological function of DUSP3 has remained elusive. Results Using immunohistochemistry on human cervical sections, we observed a strong expression of DUSP3 in endothelial cells (EC) suggesting a contribution for this phosphatase to EC functions. DUSP3 downregulation, using RNA interference, in human EC reduced significantly in vitro tube formation on Matrigel and spheroid angiogenic sprouting. However, this defect was not associated with an altered phosphorylation of the documented in vitro DUSP3 substrates, ERK1/2, JNK1/2 and EGFR but was associated with an increased PKC phosphorylation. To investigate the physiological function of DUSP3, we generated Dusp3-deficient mice by homologous recombination. The obtained DUSP3-/- mice were healthy, fertile, with no spontaneous phenotype and no vascular defect. However, DUSP3 deficiency prevented neo-vascularization of transplanted b-FGF containing Matrigel and LLC xenograft tumors as evidenced by hemoglobin (Hb) and FITC-dextran quantifications. Furthermore, we found that DUSP3 is required for b-FGF-induced microvessel outgrowth in the aortic ring assay. Conclusions All together, our data identify DUSP3 as a new important player in angiogenesis. [less ▲]Detailed reference viewed: 77 (22 ULg)
Bone marrow-derived mesenchymal stem cells drive lymphangiogenesis.
Maertens, Ludovic ; Erpicum, Charlotte ; Detry, Benoît et al
in PLoS ONE (2014), 9(9), 106976
It is now well accepted that multipotent Bone-Marrow Mesenchymal Stem Cells (BM-MSC) contribute to cancer progression through several mechanisms including angiogenesis. However, their involvement during ... [more ▼]
It is now well accepted that multipotent Bone-Marrow Mesenchymal Stem Cells (BM-MSC) contribute to cancer progression through several mechanisms including angiogenesis. However, their involvement during the lymphangiogenic process is poorly described. Using BM-MSC isolated from mice of two different backgrounds, we demonstrate a paracrine lymphangiogenic action of BM-MSC both in vivo and in vitro. Co-injection of BM-MSC and tumor cells in mice increased the in vivo tumor growth and intratumoral lymphatic vessel density. In addition, BM-MSC or their conditioned medium stimulated the recruitment of lymphatic vessels in vivo in an ear sponge assay, and ex vivo in the lymphatic ring assay (LRA). In vitro, MSC conditioned medium also increased the proliferation rate and the migration of both primary lymphatic endothelial cells (LEC) and an immortalized lymphatic endothelial cell line. Mechanistically, these pro-lymphangiogenic effects relied on the secretion of Vascular Endothelial Growth Factor (VEGF)-A by BM-MSC that activates VEGF Receptor (VEGFR)-2 pathway on LEC. Indeed, the trapping of VEGF-A in MSC conditioned medium by soluble VEGF Receptors (sVEGFR)-1, -2 or the inhibition of VEGFR-2 activity by a specific inhibitor (ZM 323881) both decreased LEC proliferation, migration and the phosphorylation of their main downstream target ERK1/2. This study provides direct unprecedented evidence for a paracrine lymphangiogenic action of BM-MSC via the production of VEGF-A which acts on LEC VEGFR-2. [less ▲]Detailed reference viewed: 25 (3 ULg)
Improved computer-assisted analysis of the global lymphatic network in human cervical tissues.
Balsat, Cédric ; ; GOFFIN, Frédéric et al
in Modern Pathology : An Official Journal of the United States & Canadian Academy of Pathology, Inc (2014), 27(6), 887-98
Lymphatic dissemination is a key event in cervical cancer progression and related tumor lymphatic markers are viewed as promising prognostic factor of nodal extension. However, validating such parameters ... [more ▼]
Lymphatic dissemination is a key event in cervical cancer progression and related tumor lymphatic markers are viewed as promising prognostic factor of nodal extension. However, validating such parameters requires an objective characterization of the lymphatic vasculature. Here, we performed a global analysis of the lymphatic network using a new computerized method applied on whole uterine cervical digital images. Sixty-eight cases of cervical neoplasia (12 CIN3, 10 FIGO stage 1A and 46 stage IB1) and 10 cases of normal cervical tissue were reacted with antibodies raised against D2-40, D2-40/p16 and D2-40/Ki67. Immunostained structures were automatically detected on whole slides. The lymphatic vessel density (D2-40), proliferating lymphatic vessel density (D2-40/ki67) and spatial lymphatic distribution in respect to the adjacent epithelium were assessed from normal cervix to early cervical cancer and correlated with lymphovascular space invasion and lymph node status. Prominent lymphatic vessel density and proliferating lymphatic vessel density are detected under the transformation zone of benign cervix and no further increase is noted during cancer progression. Notably, a shift of lymphatic vessel distribution toward the neoplastic edges is detected. In IB1 cervical cancer, although intra- and peritumoral lymphatic vessel density are neither correlated with lymphovascular space invasion nor with lymph node metastasis, a specific spatial distribution with more lymphatic vessels in the vicinity of tumor edges is predictive of lymphatic dissemination. Herein, we provide a new computerized method suitable for an innovative detailed analysis of the lymphatic network. We show that the transformation zone of the benign cervix acts as a baseline lymphangiogenic niche before the initiation of neoplastic process. During cancer progression, this specific microenvironment is maintained with lymphatic vessels even in closer vicinity to tumor cells.Modern Pathology advance online publication, 6 December 2013; doi:10.1038/modpathol.2013.195. [less ▲]Detailed reference viewed: 56 (20 ULg)
Blocking lipid synthesis overcomes tumor re-growth and metastasis after anti-angiogenic therapy withdrawal.
Sounni, Nor Eddine ; Cimino, Jonathan ; BLACHER, Silvia et al
in Cell Metabolism (2014), 20(2), 280-94
The molecular mechanisms responsible for the failure of antiangiogenic therapies and how tumors adapt to these therapies are unclear. Here, we applied transcriptomic, proteomic, and metabolomic approaches ... [more ▼]
The molecular mechanisms responsible for the failure of antiangiogenic therapies and how tumors adapt to these therapies are unclear. Here, we applied transcriptomic, proteomic, and metabolomic approaches to preclinical models and provide evidence for tumor adaptation to vascular endothelial growth factor blockade through a metabolic shift toward carbohydrate and lipid metabolism in tumors. During sunitinib or sorafenib treatment, tumor growth was inhibited and tumors were hypoxic and glycolytic. In sharp contrast, treatment withdrawal led to tumor regrowth, angiogenesis restoration, moderate lactate production, and enhanced lipid synthesis. This metabolic shift was associated with a drastic increase in metastatic dissemination. Interestingly, pharmacological lipogenesis inhibition with orlistat or fatty acid synthase downregulation with shRNA inhibited tumor regrowth and metastases after sunitinib treatment withdrawal. Our data shed light on metabolic alterations that result in cancer adaptation to antiangiogenic treatments and identify key molecules involved in lipid metabolism as putative therapeutic targets. [less ▲]Detailed reference viewed: 89 (31 ULg)
Cell invasion in the spheroid sprouting assay: a spatial organisation analysis adaptable to cell behaviour.
Blacher, Silvia ; Erpicum, Charlotte ; et al
in PLoS ONE (2014), 9(5), 97019
The endothelial cell spheroid assay provides a suitable in vitro model to study (lymph) angiogenesis and test pro- and anti-(lymph) angiogenic factors or drugs. Usually, the extent of cell invasion ... [more ▼]
The endothelial cell spheroid assay provides a suitable in vitro model to study (lymph) angiogenesis and test pro- and anti-(lymph) angiogenic factors or drugs. Usually, the extent of cell invasion, observed through optical microscopy, is measured. The present study proposes the spatial distribution of migrated cells as a new descriptor of the (lymph) angiogenic response. The utility of this novel method rests with its capacity to locally characterise spheroid structure, allowing not only the investigation of single and collective cell invasion but also the evolution of the spheroid core itself. Moreover, the proposed method can be applied to 2D-projected spheroid images obtained by optical microscopy, as well as to 3D images acquired by confocal microscopy. To validate the proposed methodology, endothelial cell invasion was evaluated under different experimental conditions. The results were compared with widely used global parameters. The comparison shows that our method prevents local spheroid modifications from being overlooked and leading to the possible misinterpretation of results. [less ▲]Detailed reference viewed: 33 (5 ULg)
Changes in elastin density in different locations of the vaginal wall in women with pelvic organ prolapse.
DE LANDSHEERE, Laurent ; Blacher, Silvia ; Munaut, Carine et al
in International Urogynecology Journal & Pelvic Floor Dysfunction (2014)
INTRODUCTION AND HYPOTHESIS: The purpose of this study was to analyze the histomorphometric properties of the vaginal wall in women with pelvic organ prolapse (POP). METHODS: In 15 women undergoing ... [more ▼]
INTRODUCTION AND HYPOTHESIS: The purpose of this study was to analyze the histomorphometric properties of the vaginal wall in women with pelvic organ prolapse (POP). METHODS: In 15 women undergoing surgery for POP, full-thickness biopsies were collected at two different sites of location from the anterior and/or posterior vaginal wall. Properties of the precervical area (POP-Q point C/D) were compared with the most distal portion of the vaginal wall (POP-Q point Ba/Bp) using histological staining and immunohistochemistry. The densities of total collagen fibers, elastic fibers, smooth muscle cells, and blood vessels were determined by combining high-resolution virtual imaging and computer-assisted digital image analysis. RESULTS: The mean elastin density was significantly decreased in the lamina propria and muscularis layer of the vaginal wall from the most distal portion of the prolapsed vaginal wall compared with the precervical area. This difference was statistically significant in the lamina propria for both anterior (8.4 +/- 1.2 and 12.1 +/- 2.0, p = 0.048) and posterior (6.8 +/- 0.5 and 10.1 +/- 1.4, p = 0.040) locations, and in the muscularis for the anterior (5.2 +/- 0.4 and 8.4 +/- 1.2, p = 0.009) vaginal wall. There were no statistically significant differences in the mean densities of collagen fibers, smooth muscle cells or blood vessels between the two locations. CONCLUSIONS: In this study, we observed changes in elastin density in two different locations of the vaginal wall from women with POP. The histomorphometric properties of the vaginal wall can be variable from one place to another in the same patient. This result supports the existence of most vulnerable locations within the vaginal wall and the potential benefit of site-specific prolapse surgery. [less ▲]Detailed reference viewed: 58 (12 ULg)
Effects of adenosine on lymphangiogenesis.
Lenoir, Bénédicte ; ; Blacher, Silvia et al
in PloS one (2014), 9(3), 92715
BACKGROUND: The lymphatic system controls tissue homeostasis by draining protein-rich lymph to the vascular system. Lymphangiogenesis, the formation of lymphatic vessels, is a normal event in childhood ... [more ▼]
BACKGROUND: The lymphatic system controls tissue homeostasis by draining protein-rich lymph to the vascular system. Lymphangiogenesis, the formation of lymphatic vessels, is a normal event in childhood but promotes tumor spread and metastasis during adulthood. Blocking lymphangiogenesis may therefore be of therapeutic interest. Production of adenosine is enhanced in the tumor environment and contributes to tumor progression through stimulation of angiogenesis. In this study, we determined whether adenosine affects lymphangiogenesis. METHODS: Lymphatic endothelial cells (HMVEC-dLy) were cultured in presence of adenosine and their proliferation, migration and tube formation was assessed. Gelatin sponges embedded with the stable analogue of adenosine 2-chloro adenosine were implanted in mice ear and lymphangiogenesis was quantified. Mice were intravenously injected with adenoviruses containing expression vector for 5'-endonucleotidase, which plays a major role in the formation of adenosine. RESULTS: In vitro, we observed that adenosine decreased the proliferation of lymphatic endothelial cells, their migration and tube formation. However, in vivo, gelatin sponges containing 2-chloro adenosine and implanted in mice ear displayed an elevated level of lymphangiogenesis (2.5-fold, p<0.001). Adenovirus-mediated over-expression of cytosolic 5'-nucleotidase IA stimulated lymphangiogenesis and the recruitment of macrophages in mouse liver. Proliferation of lymphatic endothelial cells was enhanced (2-fold, p<0.001) when incubated in the presence of conditioned medium from murine macrophages. CONCLUSION: We have shown that adenosine stimulates lymphangiogenesis in vivo, presumably through a macrophage-mediated mechanism. This observation suggests that blockade of adenosine receptors may help in anti-cancer therapies. [less ▲]Detailed reference viewed: 46 (2 ULg)
Lymphangiogenesis and extracellular matrix remodeling
Erpicum, Charlotte ; Detry, Benoît ; Paupert, Jenny et al
Conference (2013, January 28)Detailed reference viewed: 40 (11 ULg)
Isoform 111 of vascular endothelial growth factor (VEGF111) improves angiogenesis of ovarian tissue xenotransplantation
Labied, Soraya ; Delforge, Yves ; Munaut, Carine et al
in Transplantation (2013), 95(3), 426-433
Background: Cryopreservation of cortex ovarian tissue before anti-cancer therapy is a promising technique for fertility preservation mainly in children and young women. Ischemia in the early stage after ... [more ▼]
Background: Cryopreservation of cortex ovarian tissue before anti-cancer therapy is a promising technique for fertility preservation mainly in children and young women. Ischemia in the early stage after ovarian graft causes massive follicle loss by apoptosis. VEGF111 is a recently described VEGF isoform that does not bind to the extracellular matrix, diffuse extensively and is resistant to proteolysis. These properties confer a significantly higher angiogenic potential to VEGF111 in comparison to the other VEGF isoforms. Methods: We evaluated the morphology of cryopreserved sheep ovarian cortex, grafted in the presence or absence of VEGF111. Ovarian cortex biopsies were embedded in type I collagen with or without VEGF111 addition before transplantation to SCID mice ovaries. Transplants were retrieved 3 days or 3 weeks later. Follicular density, vasculature network, haemoglobin content and cell proliferation were analysed. Results: Addition of VEGF111 increased density of functional capillaries (p=0.01) 3 days after grafting. By double immunostaining of Ki-67 and von Willebrand Factor (vWF) we demonstrated that proliferating endothelial cells were found in 83% of the VEGF111 group when compared to 33% in the control group (p=0.001). This angio-stimulation was associated with a significant enhancement of haemoglobin content (p=0.03). Three weeks after transplantation, the number of primary follicles was significantly higher in VEGF111 grafts (p=0.02). Conclusion: VEGF111 accelerates blood vessels recruitment, functional angiogenesis and improves the viability of ovarian cortex by limiting ischemia and ovarian cortex damage. [less ▲]Detailed reference viewed: 51 (19 ULg)
Sunitinib inhibits inflammatory corneal lymphangiogenesis.
Detry, Benoît ; Blacher, Silvia ; Erpicum, Charlotte et al
in Investigative Ophthalmology & Visual Science (2013), 54(5), 3082-93
PURPOSE: To evaluate the antilymphangiogenic potential of multi-target tyrosine kinase inhibitor sunitinib in corneal neovascularization (NV). METHODS: Inflammatory corneal NV was induced by thermal ... [more ▼]
PURPOSE: To evaluate the antilymphangiogenic potential of multi-target tyrosine kinase inhibitor sunitinib in corneal neovascularization (NV). METHODS: Inflammatory corneal NV was induced by thermal cauterization applied in the central cornea of mice, to which sunitinib malate was daily administered by gavage or not. At days 6, 11, or 17 post cauterization, lymphatic and blood vessels, as well as inflammatory cells were immunostained and quantified in whole-mounted corneas. RT-PCRs were performed to evidence VEGF-A, VEGF-C, VEGF-D, placental growth factor (PlGF), and soluble vascular endothelial growth factor receptor (VEGFR)-1 and -2 (sVEGFR-1, sVEGFR-2) expressions. Macrophages were isolated from mice peritoneal cavity following thioglycollate injection to produce conditioned medium. The effects of sunitinib were evaluated in vitro in the aortic and lymphatic ring assays in the presence or not of macrophage conditioned medium. RESULTS: Sunitinib treatment drastically reduced pathologic corneal lymphangiogenesis and angiogenesis. Reduced F4/80+ cell infiltration was evidenced in sunitinib-treated mice and was associated to decreased VEGF-A (by 50%, P < 0.01) and VEGF-C (by 35%, P < 0.01) expressions, while VEGF-D and sVEGFR-2 expressions were not affected. In vitro, sunitinib dose-dependently inhibited aortic ring outgrowth, but failed to affect lymphangiogenesis in the lymphatic ring assay. However, macrophage conditioned medium-enhanced angiogenesis and lymphangiogenesis were both strongly counteracted by sunitinib treatment. Mechanistically, sunitinib blocked VEGFR-2 phosphorylation induced by VEGF-A released by macrophages. CONCLUSIONS: Sunitinib exerts antihemangiogenic and antilymphangiogenic effects in vivo by reducing F4/80+ cell recruitment and interacting with their released factors. [less ▲]Detailed reference viewed: 34 (9 ULg)
Towards Lipidomics of Low-Abundant Species for Exploring Tumor Heterogeneity Guided by High-Resolution Mass Spectrometry Imaging
Cimino, Jonathan ; ; Far, Johann et al
in International Journal of Molecular Sciences (2013), 14
Many studies have evidenced the main role of lipids in physiological and also pathological processes such as cancer, diabetes or neurodegenerative diseases. The identification and the in situ localization ... [more ▼]
Many studies have evidenced the main role of lipids in physiological and also pathological processes such as cancer, diabetes or neurodegenerative diseases. The identification and the in situ localization of specific low-abundant lipid species involved in cancer biology are still challenging for both fundamental studies and lipid marker discovery. In this paper, we report the identification and the localization of specific isobaric minor phospholipids in human breast cancer xenografts by FTICR MALDI imaging supported by histochemistry. These potential candidates can be further confirmed by liquid chromatography coupled with electrospray mass spectrometry (LC-ESI-MS) after extraction from the region of interest defined by MALDI imaging. Finally, this study highlights the importance of characterizing the heterogeneous distribution of low-abundant lipid species, relevant in complex histological samples for biological purposes. [less ▲]Detailed reference viewed: 39 (8 ULg)
Laser-induced choroidal neovascularization model to study age-related macular degeneration in mice.
LAMBERT, Vincent ; Lecomte, Julie ; Hansen, Sylvain et al
in Nature Protocols (2013), 8(11), 2197-2211
The mouse model of laser-induced choroidal neovascularization (CNV) has been used extensively in studies of the exudative form of age-related macular degeneration (AMD). This experimental in vivo model ... [more ▼]
The mouse model of laser-induced choroidal neovascularization (CNV) has been used extensively in studies of the exudative form of age-related macular degeneration (AMD). This experimental in vivo model relies on laser injury to perforate Bruch's membrane, resulting in subretinal blood vessel recruitment from the choroid. By recapitulating the main features of the exudative form of human AMD, this assay has served as the backbone for testing antiangiogenic therapies. This standardized protocol can be applied to transgenic mice and can include treatments with drugs, recombinant proteins, antibodies, adenoviruses and pre-microRNAs to aid in the search for new molecular regulators and the identification of novel targets for innovative treatments. This robust assay requires 7-14 d to complete, depending on the treatment applied and whether immunostaining is performed. This protocol includes details of how to induce CNV, including laser induction, lesion excision, processing and different approaches to quantify neoformed vasculature. [less ▲]Detailed reference viewed: 81 (32 ULg)