References of "Blacher, Silvia"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailCharacterization of the pre-metastatic niche in lymph node, in experimental and clinical settings
Noël, Agnès ULiege; Balsat, Cédric; Garcia Caballero, Melissa et al

Poster (2017, June 08)

Detailed reference viewed: 31 (7 ULiège)
Peer Reviewed
See detailNON-INVASIVE ANALYSIS OF POTENTIALLY DYSREGULATED MIRNAS IN ENDOMETRIOSIS
Munaut, Carine ULiege; Emonard, Violaine; TIMMERMANS, Marie ULiege et al

Conference (2017, May 17)

Detailed reference viewed: 23 (3 ULiège)
Full Text
Peer Reviewed
See detailActivational and organizational disruption of folliculogenesis and estrous cycle caused by exposure to Bisphenol A (BPA) during early postnatal or adult life
Lopez Rodriguez, David ULiege; Franssen, Delphine ULiege; GERARD, Arlette ULiege et al

Conference (2017, May 05)

Our previous studies have shown that an early postnatal exposure to a very low dose of bisphenol A (BPA) disrupts sexual maturation and pubertal timing. However, the long-term effects of such low dose ... [more ▼]

Our previous studies have shown that an early postnatal exposure to a very low dose of bisphenol A (BPA) disrupts sexual maturation and pubertal timing. However, the long-term effects of such low dose exposure as well as the effects of adult exposure have not been studied. One day-old and 90 day-old female rats received daily subcutaneous injections of corn oil (vehicle) or BPA (25ng/kg/d or 5mg/kg/d) for 15 days. The early postnatal exposure to both BPA doses significantly decreased the percentage of females with a regular cycle (BPA-25ng: 51±15%; BPA-5mg: 7±7%; OIL: 86±2%). The estrus cycle alterations were characterized by a decrease in time spent in proestrus (BPA-25ng: 13±3%; BPA-5mg: 12±3%; OIL: 18±3%). During adult exposure, both doses caused a disruption of the estrous cycle characterized by a significant decrease in the average time spent in proestrus (BPA-25ng: 19±2%; BPA-5mg: 17±1%; OIL: 23±1%). This effect was transient as the exposed females showed a regular cycle one month after the last dose of BPA. After adult exposure, we also observed a disruption of folliculogenesis characterized by a significant decrease of antral follicles (BPA-25ng: 21±2%; BPA-5mg: 21±2%; OIL: 36±2%) and increase of atretic follicles (BPA-25ng: 24±4%; BPA-5mg: 26±6%; OIL: 15±1%). GnRH secretion measured ex vivo 24h after adult exposure was moderately affected by BPA. Indeed, GnRH interpulse interval was significantly different when comparing animals exposed to the high or low dose of BPA but not when comparingexposed animals to the control group (BPA-25ng: 42.6±0.5; BPA-5mg: 40.2±0.6%; OIL: 41.1±0,2minutes±SEM). In conclusion, while exposure to BPA produces persistent alterations of the estrous cycle after early postnatal exposure, exposure during adulthood appears to cause activational non-persistent alternations of both the estrous cycle and folliculogenesis. [less ▲]

Detailed reference viewed: 65 (6 ULiège)
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 ▲]

Detailed reference viewed: 62 (2 ULiège)
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 ▲]

Detailed reference viewed: 34 (4 ULiège)
Full Text
Peer Reviewed
See detailZonula occludens-1/NF-κB/CXCL8: a new regulatory axis for tumor angiogenesis.
Lesage, Julien; Suarez-Carmona, Meggy; Neyrinck-Leglantier, Deborah et al

in FASEB Journal (2017), 31(4), 1678-1688

Zonula occludens-1 (ZO-1) is a submembrane scaffolding protein that may display proinvasive functions when it relocates from tight junctions into the cytonuclear compartment. This article examines the ... [more ▼]

Zonula occludens-1 (ZO-1) is a submembrane scaffolding protein that may display proinvasive functions when it relocates from tight junctions into the cytonuclear compartment. This article examines the functional involvement of ZO-1 in CXCL8/IL-8 chemokine expression in lung and breast tumor cells. ZO-1 small interfering RNA and cDNA transfection experiments emphasized regulation of CXCL8/IL-8 expression via a cytonuclear pool of ZO-1. Luciferase reporter assays highlighted a 173-bp region of CXCL8/IL-8 promoter that responded to ZO-1. Moreover, by using mutated promoter constructs, we identified a NF-κB site as critical in this activation. Furthermore, NF-κB pathway signaling analysis revealed both IκBα and p65 phosphorylation in ZO-1-overexpressing cells, and subsequent p65 silencing validated its requirement for CXCL8/IL-8 induction. Investigation of the functional implication of this regulatory axis next showed the proangiogenic activity of ZO-1 in both ex vivo and in vivo angiogenesis assays. Finally, we found that non-small-cell lung carcinoma that presented a cytonuclear ZO-1 pattern was significantly more angiogenic that that without detectable cytonuclear ZO-1 expression. Taken together, our results demonstrate that ZO-1 regulates CXCL8/IL-8 expression via the NF-κB signaling pathway and its p65 subunit, which subsequently modulates the transcription of IL-8. We also provide evidence of a newly identified regulatory pathway that could promote angiogenesis. Thus, our results support the concept that the ZO-1 shuttle from the cell junction to the cytonuclear compartment may affect both the intrinsic invasive properties of tumor cells and the establishment of the protumoral microenvironment. [less ▲]

Detailed reference viewed: 28 (2 ULiège)
Full Text
Peer Reviewed
See detailA specific immune and lymphatic profile characterizes the pre-metastatic state of the sentinel lymph node in patients with early cervical cancer
Balsat, Cédric ULiege; Blacher, Silvia ULiege; Herfs, Michael ULiege et al

in Oncoimmunology (2017), 6(2), 1265718

The lymph node (LN) pre-metastatic niche is faintly characterized in lymphophilic human neoplasia, although LN metastasis is considered as the strongest prognostic marker of patient survival. Due to its ... [more ▼]

The lymph node (LN) pre-metastatic niche is faintly characterized in lymphophilic human neoplasia, although LN metastasis is considered as the strongest prognostic marker of patient survival. Due to its specific dissemination through a complex bilateral pelvic lymphatic system, early cervical cancer is a relevant candidate for investigating the early nodal metastatic process. In the present study, we analyzed in-depth both the lymphatic vasculature and the immune climate of pre-metastatic sentinel LN (SLN), in 48 cases of FIGO stage IB1 cervical neoplasms. An original digital image analysis methodology was used to objectively determine whole slide densities and spatial distributions of immunostained structures. We observed a marked increase in lymphatic vessel density (LVD) and a specific capsular and subcapsular distribution in pre-metastatic SLN when compared with non-sentinel counterparts. Such features persisted in the presence of nodal metastatic colonization. The inflammatory profile attested by CD8+, Foxp3, CD20 and PD-1expression was also significantly increased in pre-metastatic SLN. Remarkably, the densities of CD20+ B cells and PD-1 expressing germinal centers were positively correlated with LVD. All together, these data strongly support the existence of a pre-metastatic dialog between the primary tumor and the first nodal relay. Both lymphatic and immune responses contribute to the elaboration of a specific pre-metastatic microenvironment in human SLN. Moreover, this work provides evidence that, in the context of early cervical cancer, a pre-metastatic lymphangiogenesis occurs within the SLN (pre-metastatic niche) and is associated with a specific humoral immune response. [less ▲]

Detailed reference viewed: 99 (23 ULiège)
Full Text
Peer Reviewed
See detailTargeting VEGFR-3/-2 signaling pathways with AD0157: a potential strategy against tumor-associated lymphangiogenesis and lymphatic metastases.
Garcia-Caballero, Melissa; Paupert, Jenny; Blacher, Silvia ULiege et al

in Journal of Hematology & Oncology (2017), 10(1), 122

BACKGROUND: Lymphatic metastasis is one of the leading causes of death in patients with different types of cancer and is the main prognostic factor for the disease survival. The formation of new lymphatic ... [more ▼]

BACKGROUND: Lymphatic metastasis is one of the leading causes of death in patients with different types of cancer and is the main prognostic factor for the disease survival. The formation of new lymphatic vessels (lymphangiogenesis) in primary tumors facilitates tumor cell dissemination to regional lymph nodes and correlates with distant metastases. Lymphangiogenesis has thus emerged as a suitable therapeutic target to block metastases, but no anti-lymphangiogenic compounds have been approved for clinical use to date. Therefore, new or improved therapies blocking lymphatic metastases are urgently required. METHODS: We established murine breast tumors to assess the effect of AD0157 on tumor growth, lymphangiogenesis, and lymphatic dissemination. Then, a battery of in vivo (mouse corneal neovascularization and ear sponges), ex vivo (mouse lymphatic rings and rat mesentery explants), and in vitro (proliferation, tubulogenesis, wound-healing, Boyden chambers, and spheroids) assays was used to give insight into the lymphangiogenic steps affected by AD0157. Finally, we investigated the molecular pathways controlled by this drug. RESULTS: AD0157 was found to inhibit the growth of human breast cancer xenografts in mice, to strongly reduce tumor-associated lymphangiogenesis and to block metastatic dissemination to both lymph nodes and distant organs. The high anti-lymphangiogenic potency of AD0157 was further supported by its inhibitory activity at low micromolar range in two in vivo pathological models and in two ex vivo assays. In addition, AD0157 inhibited lymphatic endothelial cell proliferation, migration and invasion, cellular sprouting, and tube formation. Mechanistically, this compound induced apoptosis in lymphatic endothelial cells and decreased VEGFR-3/-2, ERK1/2, and Akt phosphorylations. CONCLUSIONS: These findings demonstrate the suitability of AD0157 to suppress tumor-associated lymphangiogenesis. Beyond discovering a new potent anti-lymphangiogenic drug that is worth considering in future clinical settings, our study supports the interest of designing anti-lymphangiogenic therapies to avoid distant metastatic processes. [less ▲]

Detailed reference viewed: 24 (1 ULiège)
Full Text
Peer Reviewed
See detailModeling pre-metastatic lymphvascular niche in the mouse ear sponge assay.
Garcia-Caballero, Melissa; Van De Velde, Maureen ULiege; Blacher, Silvia ULiege et al

in Scientific Reports (2017), 7

Lymphangiogenesis, the formation of new lymphatic vessels, occurs in primary tumors and in draining lymph nodes leading to pre-metastatic niche formation. Reliable in vivo models are becoming instrumental ... [more ▼]

Lymphangiogenesis, the formation of new lymphatic vessels, occurs in primary tumors and in draining lymph nodes leading to pre-metastatic niche formation. Reliable in vivo models are becoming instrumental for investigating alterations occurring in lymph nodes before tumor cell arrival. In this study, we demonstrate that B16F10 melanoma cell encapsulation in a biomaterial, and implantation in the mouse ear, prevents their rapid lymphatic spread observed when cells are directly injected in the ear. Vascular remodeling in lymph nodes was detected two weeks after sponge implantation, while their colonization by tumor cells occurred two weeks later. In this model, a huge lymphangiogenic response was induced in primary tumors and in pre-metastatic and metastatic lymph nodes. In control lymph nodes, lymphatic vessels were confined to the cortex. In contrast, an enlargement and expansion of lymphatic vessels towards paracortical and medullar areas occurred in pre-metastatic lymph nodes. We designed an original computerized-assisted quantification method to examine the lymphatic vessel structure and the spatial distribution. This new reliable and accurate model is suitable for in vivo studies of lymphangiogenesis, holds promise for unraveling the mechanisms underlying lymphatic metastases and pre-metastatic niche formation in lymph nodes, and will provide new tools for drug testing. [less ▲]

Detailed reference viewed: 30 (11 ULiège)
Full Text
Peer Reviewed
See detailThe role of fatty acid beta-oxidation in lymphangiogenesis.
Wong, Brian W.; Wang, Xingwu; Zecchin, Annalisa et al

in Nature (2017), 542(49),

Lymphatic vessels are lined by lymphatic endothelial cells (LECs), and are critical for health. However, the role of metabolism in lymphatic development has not yet been elucidated. Here we report that in ... [more ▼]

Lymphatic vessels are lined by lymphatic endothelial cells (LECs), and are critical for health. However, the role of metabolism in lymphatic development has not yet been elucidated. Here we report that in transgenic mouse models, LEC-specific loss of CPT1A, a rate-controlling enzyme in fatty acid beta-oxidation, impairs lymphatic development. LECs use fatty acid beta-oxidation to proliferate and for epigenetic regulation of lymphatic marker expression during LEC differentiation. Mechanistically, the transcription factor PROX1 upregulates CPT1A expression, which increases acetyl coenzyme A production dependent on fatty acid beta-oxidation. Acetyl coenzyme A is used by the histone acetyltransferase p300 to acetylate histones at lymphangiogenic genes. PROX1-p300 interaction facilitates preferential histone acetylation at PROX1-target genes. Through this metabolism-dependent mechanism, PROX1 mediates epigenetic changes that promote lymphangiogenesis. Notably, blockade of CPT1 enzymes inhibits injury-induced lymphangiogenesis, and replenishing acetyl coenzyme A by supplementing acetate rescues this process in vivo. [less ▲]

Detailed reference viewed: 61 (3 ULiège)
Peer Reviewed
See detailDysregulated circulating miRNAs in pre-eclampsia
Tebache, Linda; Munaut, Carine ULiege; Blacher, Silvia ULiege et al

Conference (2016, September 25)

Detailed reference viewed: 19 (5 ULiège)
Full Text
Peer Reviewed
See detailNovel application assigned to toluquinol: inhibition of lymphangiogenesis by interfering with VEGF-C/VEGFR-3 signaling pathway.
Garcia-Caballero, Melissa; Blacher, Silvia ULiege; Paupert, J. et al

in British Journal of Pharmacology (2016), 173(12), 1966-87

BACKGROUND AND PURPOSE: Lymphangiogenesis is an important biological process associated with the pathogenesis of several diseases, including metastatic dissemination, graft rejection, lymphedema and other ... [more ▼]

BACKGROUND AND PURPOSE: Lymphangiogenesis is an important biological process associated with the pathogenesis of several diseases, including metastatic dissemination, graft rejection, lymphedema and other inflammatory disorders. The development of new drugs blocking lymphangiogenesis has become a promising therapeutic strategy. In this study, we aim at investigating the ability of toluquinol, a 2-methyl-hydroquinone isolated from the culture broth of the marine fungus Penicillium sp. HL-85-ALS5-R004, to inhibit lymphangiogenesis in vitro, ex vivo and in vivo. EXPERIMENTAL APPROACH: We used human lymphatic endothelial cells (LEC) to analyze the effect of toluquinol in 2D and 3D in vitro cultures, and in the ex vivo mouse lymphatic ring assay. For in vivo approaches, the transgenic Fli1:eGFPy1 zebrafish, the mouse ear sponges and cornea models were used. Western-blotting and apoptosis analyses were carried out to search for drug targets. KEY RESULTS: Toluquinol inhibited LEC proliferation, migration, tubulogenesis and sprouting of new lymphatic vessels. Furthermore, toluquinol induced LEC apoptosis after 14 h of treatment in vitro, blocked the thoracic duct development in zebrafish, and reduced the VEGF-C-induced lymphatic vessel formation and corneal neovascularization in mice. Mechanistically, we are providing evidence that this drug abrogates the VEGF-C-induced VEGFR-3 phosphorylation in a dose-dependent manner, and represses Akt and ERK1/2 phosphorylations. CONCLUSIONS AND IMPLICATIONS: Based on these findings, we propose toluquinol as a new candidate with pharmacological potential for the treatment of lymphangiogenesis-related pathologies. Notably, its ability to suppress corneal neovascularization paves the way for applications in vascular ocular pathologies. This article is protected by copyright. All rights reserved. [less ▲]

Detailed reference viewed: 32 (11 ULiège)
Full Text
See detailEstetrol, a natural SERM exhibiting combined estrogenic and anti-estrogenic properties on mammary gland and breast cancer
Gallez, Anne ULiege; Gérard, Céline ULiege; Blacher, Silvia ULiege et al

Poster (2016, May 30)

The increased risk of breast cancer and thromboembolism in women who take hormone replacement therapy (HRT) is a major public health problem. The discovery of new drugs with better safety profile would ... [more ▼]

The increased risk of breast cancer and thromboembolism in women who take hormone replacement therapy (HRT) is a major public health problem. The discovery of new drugs with better safety profile would provide useful advances for patient care. Estetrol (E4) is a liver friendly promising candidate for HRT. In preclinical and/or clinical studies, E4 has been effective against the main symptoms of menopause from a starting dose of 0.3 mg/kg/day. The aim of this study was to define the impact of E4 on mammary gland and breast cancer development. Our preclinical data show that E4 is less efficient than estradiol (E2) to induce mammary gland growth. Treatment with several concentrations of E4 has shown that E4 did not increase tumor development, when it is used at 0.3 mg/kg/day. However, at 3 mg/kg/day, E4 increased tumor growth similarly to E2 (0.08 mg/kg/day). E4 presents also some anti-estrogenic effects on mammary gland and antitumor activity on breast cancer by decreasing the strong proliferative effect of E2. While ERα is the predominant receptor mediating its effects, the dual weak-estrogenic/anti-estrogenic feature of E4 results from differential signaling pathways activation. Both nuclear and rapid extra-nuclear signaling pathways are necessary for a complete estrogenic effect of E4. However, the antitumor action of E4 is not due to a capacity to antagonize E2-induced nuclear activity. In conclusion, our results support that E4, if it is used in strictly controlled clinical applications, could have no or only limited impact on breast and breast cancer. [less ▲]

Detailed reference viewed: 58 (2 ULiège)