Search results for "wt"
showing 10 items of 5424 documents
Synthesis of Combretastatin A-4 and 3′-Aminocombretastatin A-4 derivatives with Aminoacid Containing Pendants and Study of their Interaction with Tub…
2020
Natural product combretastatin A-4 (CA-4) and its nitrogenated analogue 3&prime
ASTROCYTES SHED EXTRACELLULAR VESICLES THAT CONTAIN FIBROBLAST GROWTH FACTOR-2 AND VASCULAR ENDOTHELIAL GROWTH FACTOR.
2007
An important component of the pathogenic process of multiple sclerosis (MS) is the blood-brain barrier (BBB) damage. We recently set an in vitro model of BBB, based on a three-cell-type co-culture system, in which rat neurons and astrocytes synergistically induce brain capillary endothelial cells to form a monolayer with permeability properties resembling those of the physiological BBB. Herein we report that the serum from patients with secondary progressive multiple sclerosis (SPMS) has a damaging effect on isolated neurons. This finding suggests that neuronal damaging in MS could be a primary event and not only secondary to myelin damage, as generally assumed. SPMS serum affects the perme…
In vitro and in vivo arterial differentiation of human multipotent adult progenitor cells
2006
Many stem cell types have been shown to differentiate into endothelial cells (ECs); however, their specification to arterial or venous endothelium remains unexplored. We tested whether a specific arterial or venous EC fate could be induced in human multipotent adult progenitor cells (hMAPCs) and AC133(+) cells (hAC133(+)). In vitro, in the presence of VEGF(165), hAC133(+) cells only adopted a venous and microvascular EC phenotype, while hMAPCs differentiated into both arterial and venous ECs, possibly because hMAPCs expressed significantly more sonic hedgehog (Shh) and its receptors as well as Notch 1 and 3 receptors and some of their ligands. Accordingly, blocking either of those pathways …
Arthrinins A–D: Novel diterpenoids and further constituents from the sponge derived fungus Arthrinium sp.
2011
Bioassay-guided fractionation of a methanolic extract of the fungus Arthrinium sp., isolated from the Mediterranean sponge Geodia cydonium, afforded 10 natural products including five new diterpenoids, arthrinins A-D (1-4) and myrocin D (5). In addition, five known compounds were obtained, which included myrocin A (6), norlichexanthone (7), anomalin A (8), decarboxycitrinone (9) and 2,5-dimethyl-7-hydroxychromone (10). The structures of all isolated compounds were unambiguously elucidated based on extensive 1D and 2D NMR and HR-MS analyzes. The absolute configuration of arthrinins A-D (1-4) was established by the convenient Mosher method performed in NMR tubes and by interpretation of the R…
VEGF receptor signaling links inflammation and tumorigenesis in colitis-associated cancer.
2010
Inflammation drives expression of VEGFR2, which is expressed on and drives growth of tumor cells in colitis-associated cancer.
NEURONS PRODUCE FGF-2 AND VEGF SECRETE THEM AT LEST IN PART BY SHEDDING EXTRACELLULAR VESCICLES
2007
Abstract We previously found that neurons are able to affect the ability of brain capillary endothelial cells to form in vitro a monolayer with properties resembling the blood-brain barrier. We then looked, by immunofluorescence and western analysis, for factors, produced by neurons, with the potential to influence growth and differentiation of endothelial cells. In the present paper, we report that neurons produce both vascular endothelial growth factor and fibroblast growth factor 2, two well-known angiogenic factors. More interestingly, we gained evidence that both factors are released by neurons, at least in part, by shedding of extracellular vesicles, that contain β1 integrin, a membra…
Vascular endothelial growth factor gene polymorphisms in ovarian cancer
2007
Abstract Background. Polymorphisms within the vascular endothelial growth factor (VEGF) gene, the most important regulator of angiogenesis and vascular permeability, were shown to be independently associated with an impaired prognosis in various malignancies. No data have been reported in ovarian cancer. Methods. In the present multi-center study, we examined three common polymorphisms within the VEGF gene ( VEGF +405G/C, VEGF −460C/T, and VEGF +936C/T) in 553 Caucasian patients with ovarian cancer using pyrosequencing. Results. The three investigated polymorphisms did not correlate with any of the investigated clinico-pathological parameters. In univariate and multivariate models, only FIG…
Extracellular HSP27 mediates angiogenesis through Toll-like receptor 3.
2013
The heat-shock protein 27 (HSP27) is up-regulated in tumor cells and released in their microenvironment. Here, we show that extracellular HSP27 has a proangiogenic effect evidenced on chick chorioallantoic membrane. To explore this effect, we test the recombinant human protein (rhHSP27) at physiopathological doses (0.1-10 μg/ml) onto human microvascular endothelial cells (HMECs) grown as monolayers or spheroids. When added onto HMECs, rhHSP27 dose-dependently accelerates cell migration (with a peak at 5 μg/ml) and favors spheroid sprouting within 12-24 h. rhHSP27 increases VEGF gene transcription and promotes secretion of VEGF-activating VEGF receptor type 2. Increased VEGF transcription is…
Integrin-dependent and -independent functions of astrocytic fibronectin in retinal angiogenesis
2011
Fibronectin (FN) is a major component of the extracellular matrix and functions in cell adhesion, cell spreading and cell migration. In the retina, FN is transiently expressed and assembled on astrocytes (ACs), which guide sprouting tip cells and deposit a provisional matrix for sprouting angiogenesis. The precise function of FN in retinal angiogenesis is largely unknown. Using genetic tools, we show that astrocytes are the major source of cellular FN during angiogenesis in the mouse retina. Deletion of astrocytic FN reduces radial endothelial migration during vascular plexus formation in a gene dose-dependent manner. This effect correlates with reduced VEGF receptor 2 and PI3K/AKT signalli…
Reactive oxygen species activation of MAPK pathway results in VEGF upregulation as an undesired irradiation response
2013
Background Radioresistance limits the effectiveness of radiotherapy in head and neck squamous cell carcinoma. We previously demonstrated post-radiogenic mitogen-activated protein kinase (MAPK) pathway activation and vascular endothelial growth factor (VEGF) release resulting in reduced tumor cell response. Here, we examined the association of this mechanism with the induction of reactive oxygen species (ROS) under irradiation (IR). Methods Intracellular ROS after IR were measured. We modeled radiation-induced ROS by exposure of two SCC lines to H2O2 and evaluated the impact of irradiation and ROS on ERK phosphorylation by Western blot, immunohistochemistry, and ELISA. Results We found eleva…