Co-delivery of vascular endothelial growth factor and angiopoietin-1 using injectable microsphere/hydrogel hybrid systems for therapeutic angiogenesis.

PubMed

Shin, Seung-Hwa; Lee, Jangwook; Ahn, Dong-Gyun; Lee, Kuen Yong

2013-08-01

We hypothesized that combined delivery of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) using microsphere/hydrogel hybrid systems could enhance mature vessel formation compared with administration of each factor alone. Hybrid delivery systems composed of alginate hydrogels and poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres containing angiogenic factors were prepared. The release behavior of angiogenic factors from hybrid systems was monitored in vitro. The hybrid systems were injected into an ischemic rodent model, and blood vessel formation at the ischemic site was evaluated. The sustained release over 4 weeks of both VEGF and Ang-1 from hybrid systems was achieved in vitro. Co-delivery of VEGF and Ang-1 was advantageous to retain muscle tissues and significantly induced vessel enlargement at the ischemic site, compared to mice treated with either VEGF or Ang-1 alone. Sustained and combined delivery of VEGF and Ang-1 significantly enhances vessel enlargement at the ischemic site, compared with sustained delivery of either factor alone. Microsphere/hydrogel hybrid systems may be a promising vehicle for delivery of multiple drugs for many therapeutic applications.

Emerging vascular endothelial growth factor antagonists to treat neovascular age-related macular degeneration.

PubMed

Hussain, Rehan M; Ciulla, Thomas A

2017-09-01

Evolving anti-vascular endothelial growth factor (VEGF) treatments for neovascular age-related macular degeneration (nAMD) include long acting agents, combination strategies involving new pathways, topical agents, sustained-release, and genetic therapy strategies. Areas covered: Brolucizumab and abicipar pegol have smaller molecular size, facilitating higher concentrations and potentially longer duration than current anti-VEGF agents. Agents being combined with anti-VEGFs include OPT-302 (to inhibit VEGF-C and VEGF-D); pegpleranib and rinucumab (to inhibit platelet derived growth factor, PDGF - but both failed to show consistently improved visual outcomes compared to anti-VEGF monotherapy); and RG7716, ARP-1536 and nesvacumab (to activate the Tie-2 tyrosine kinase receptor, which reduces permeability). X-82 is an oral anti-VEGF and anti-PDGF being tested in phase 2 studies. Topical anti-VEGF ± anti-PDGF drugs under study include pazopanib, PAN-90806, squalamine lactate, regorafinib, and LHA510. Sustained-release anti-VEGF delivery treatments, such as the ranibizumab Port Delivery System, GB-102, NT-503, hydrogel depot, Durasert, and ENV1305 aim to reduce the burden of frequent injections. Gene therapies with new viral vectors hold the potential to induce sustained expression of anti-angiogenic proteins via the retina's cellular apparatus, and include AVA-101/201, ADVM-202/302, AAV2-sFLT01, RGX314, and Retinostat. Expert opinion: There are many emerging anti-VEGF treatments that aim to improve visual outcomes and reduce the treatment burden of nAMD.

Bone marrow-derived mesenchymal stem cells from early diffuse systemic sclerosis exhibit a paracrine machinery and stimulate angiogenesis in vitro.

PubMed

Guiducci, Serena; Manetti, Mirko; Romano, Eloisa; Mazzanti, Benedetta; Ceccarelli, Claudia; Dal Pozzo, Simone; Milia, Anna Franca; Bellando-Randone, Silvia; Fiori, Ginevra; Conforti, Maria Letizia; Saccardi, Riccardo; Ibba-Manneschi, Lidia; Matucci-Cerinic, Marco

2011-11-01

To characterise bone marrow-derived mesenchymal stem cells (MSCs) from patients with systemic sclerosis (SSc) for the expression of factors implicated in MSC recruitment at sites of injury, angiogenesis and fibrosis. The study also analysed whether the production/release of bioactive mediators by MSCs were affected by stimulation with cytokines found upregulated in SSc serum and tissues, and whether MSCs could modulate dermal microvascular endothelial cell (MVEC) angiogenesis. MSCs obtained from five patients with early severe diffuse SSc (SSc-MSCs) and five healthy donors (H-MSCs) were stimulated with vascular endothelial growth factor (VEGF), transforming growth factor β (TGFβ) or stromal cell-derived factor-1 (SDF-1). Transcript and protein levels of SDF-1 and its receptor CXCR4, VEGF, TGFβ(1) and receptors TβRI and TβRII were evaluated by quantitative real-time PCR, western blotting and confocal microscopy. VEGF, SDF-1 and TGFβ(1) secretion in culture supernatant was measured by ELISA. MVEC capillary morphogenesis was performed on Matrigel with the addition of MSC-conditioned medium. In SSc-MSCs the basal expression of proangiogenic SDF-1/CXCR4 and VEGF was significantly increased compared with H-MSCs. SSc-MSCs constitutively released higher levels of SDF-1 and VEGF. SDF-1/CXCR4 were upregulated after VEGF stimulation and CXCR4 redistributed from the cytoplasm to the cell surface. VEGF was increased by SDF-1 challenge. VEGF, TGFβ and SDF-1 stimulation upregulated TGFβ(1), TβRI and TβRII in SSc-MSCs. TβRII redistributed from the cytoplasm to focal adhesion contacts. SSc-MSC-conditioned medium showed a greater proangiogenic effect on MVECs than H-MSCs. Experiments with blocking antibodies showed that MSC-derived cytokines were responsible for this potent proangiogenic effect. SSc-MSCs constitutively overexpress and release bioactive mediators/proangiogenic factors and potentiate dermal MVEC angiogenesis.

Carbon nanotubes as VEGF carriers to improve the early vascularization of porcine small intestinal submucosa in abdominal wall defect repair

PubMed Central

Liu, Zhengni; Feng, Xueyi; Wang, Huichun; Ma, Jun; Liu, Wei; Cui, Daxiang; Gu, Yan; Tang, Rui

2014-01-01

Insufficient early vascularization in biological meshes, resulting in limited host tissue incorporation, is thought to be the primary cause for the failure of abdominal wall defect repair after implantation. The sustained release of exogenous angiogenic factors from a biocompatible nanomaterial might be a way to overcome this limitation. In the study reported here, multiwalled carbon nanotubes (MWNT) were functionalized by plasma polymerization to deliver vascular endothelial growth factor165 (VEGF165). The novel VEGF165-controlled released system was incorporated into porcine small intestinal submucosa (PSIS) to construct a composite scaffold. Scaffolds incorporating varying amounts of VEGF165-loaded functionalized MWNT were characterized in vitro. At 5 weight percent MWNT, the scaffolds exhibited optimal properties and were implanted in rats to repair abdominal wall defects. PSIS scaffolds incorporating VEGF165-loaded MWNT (VEGF–MWNT–PSIS) contributed to early vascularization from 2–12 weeks postimplantation and obtained more effective collagen deposition and exhibited improved tensile strength at 24 weeks postimplantation compared to PSIS or PSIS scaffolds, incorporating MWNT without VEGF165 loading (MWNT–PSIS). PMID:24648727

Enhanced angiogenesis and osteogenesis in critical bone defects by the controlled release of BMP-2 and VEGF: implantation of electron beam melting-fabricated porous Ti6Al4V scaffolds incorporating growth factor-doped fibrin glue.

PubMed

Lv, Jia; Xiu, Peng; Tan, Jie; Jia, Zhaojun; Cai, Hong; Liu, Zhongjun

2015-06-24

Electron beam melting (EBM)-fabricated porous titanium implants possessing low elastic moduli and tailored structures are promising biomaterials for orthopedic applications. However, the bio-inert nature of porous titanium makes reinforcement with growth factors (GFs) a promising method to enhance implant in vivo performance. Bone-morphogenic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) are key factors of angiogenesis and osteogenesis. Therefore, the present study is aimed at evaluating EBM-fabricated porous titanium implants incorporating GF-doped fibrin glue (FG) as composite scaffolds providing GFs for improvement of angiogenesis and osteogenesis in rabbit femoral condyle defects. BMP-2 and VEGF were added into the constituent compounds of FG, and then this GF-doped FG was subsequently injected into the porous scaffolds. In five groups of implants, angiogenesis and osteogenesis were evaluated at 4 weeks post-implantation using Microfil perfusion and histological analysis: eTi (empty scaffolds), cTi (containing undoped FG), BMP/cTi (containing 50 μg rhBMP-2), VEGF/cTi (containing 0.5 μg VEGF) and Dual/cTi (containing 50 μg rhBMP-2 and 0.5 μg VEGF). The results demonstrate that these composite implants are biocompatible and provide the desired gradual release of the bioactive growth factors. Incorporation of GF delivery, whether a single factor or dual factors, significantly enhanced both angiogenesis and osteogenesis inside the porous scaffolds. However, the synergistic effect of the dual factors combination was observable on angiogenesis but absent on osteogenesis. In conclusion, fibrin glue is a biocompatible material that could be employed as a delivery vehicle in EBM-fabricated porous titanium for controlled release of BMP-2 and VEGF. Application of this method for loading a porous titanium scaffold to incorporate growth factors is a convenient and promising strategy for improving osteogenesis of critical-sized bone defects.

Improvement in autologous human fat transplant survival with SVF plus VEGF-PLA nano-sustained release microspheres.

PubMed

Li, Liqun; Pan, Shengsheng; Ni, Binting; Lin, Yuanshao

2014-08-01

Early neovascularization is important for autologous fat transplant survival. SVF cells are ideal seed cells. Both vascular endothelial growth factor (VEGF) and SVF cells can promote neovascularization. However, the half-life (about 50 min) of VEGF is too short to sustain an adequate local concentration. We have investigated whether VEGF-polylactic acid (PLA) nano-sustained release microspheres plus SVF cells can improve neovascularization and survival of transplanted fat tissues. SVF cells were harvested and constructed VEGF-PLA nano-sustained release microspheres in vitro. Human fat tissues was mixed with SVF cells plus VEGF-PLA, SVF cells alone or Dulbecco's modified Eagle's medium as the control. These three mixtures were injected into random sites in 18 nude mice. Two months later, the transplants were weighed and examined histologically; and capillaries were counted to quantify neovascularization. Hematoxylin-eosin (HE) and anti-VEGF stains were applied to reveal cell infiltration. The mean wet weight of fat in the SVF plus VEGF-PLA, SVF alone, and control transplants were 0.18 ± 0.013 g, 0.16 ± 0.015 g, and 0.071 ± 0.12 g, respectively; the differences between groups were statistically significant. More vessels were present in the SVF plus VEGF-PLA transplants than in the other two types. Transplants mixed with SVF cells also had an acceptable density of capillaries. Histological analysis revealed that both the SVF plus VEGF-PLA and SVF alone transplants, but not the control transplants, were composed of adipose tissue, and had less fat necrosis and less fibrosis than control specimens. SVF plus VEGF-PLA transplants had significantly greater capillary density and VEGF expression than the other two transplant groups. Thus transplanted fat tissue survival and quality can be enhanced by the addition of VEGF-PLA nano-sustained release microspheres plus SVF cells. © 2014 International Federation for Cell Biology.

Enhancement of VEGF-Mediated Angiogenesis by 2-N,6-O-Sulfated Chitosan-Coated Hierarchical PLGA Scaffolds.

PubMed

Yu, Yuanman; Chen, Jie; Chen, Rui; Cao, Lingyan; Tang, Wei; Lin, Dan; Wang, Jing; Liu, Changsheng

2015-05-13

Rapid and controlled vascularization within scaffolds remains one of the key limitations in tissue engineering applications. This study describes the fabrication and characterization of 2-N,6-O-sulfated chitosan (26SCS)-coated hierarchical scaffold composed of poly(lactic-co-glycolic acid) (PLGA) microspheres, as a desirable vehicle for vascular endothelial growth factor (VEGF) delivery and consequent angiogenic boosting in vitro. Owing to the hierarchical porous structure and high affinity between VEGF and 26SCS, the 26SCS-modified PLGA (S-PLGA) scaffold possesses excellent entrapment and sustained release of VEGF. Using human umbilical vein endothelial cells (HUVECs) as a cell model, the VEGF-loaded S-PLGA scaffold shows desirable cell viability and attachment. The bioactivity of released VEGF is validated by intracellular nitric oxide secretion and capillary tube formation, demonstrating the improved capacity of VEGF-mediated pro-angiogenesis ascribed to 26SCS incorporation. Such a strategy will afford an effective method to prepare a scaffold with promoted angiogenesis.

Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sevostyanova, V. V., E-mail: sevostyanova.victoria@gmail.com; Khodyrevskaya, Y. I.; Glushkova, T. V.

The development of tissue-engineered small-diameter vascular grafts is an urgent issue in cardiovascular surgery. In this study, we assessed how the incorporation of the vascular endothelial growth factor (VEGF) affects morphological and mechanical properties of polycaprolactone (PCL) vascular grafts along with its release kinetics. Vascular grafts were prepared using two-phase electrospinning. In pursuing our aims, we performed scanning electron microscopy, mechanical testing, and enzyme-linked immunosorbent assay. Our results demonstrated the preservation of a highly porous structure and improvement of PCL/VEGF scaffold mechanical properties as compared to PCL grafts. A prolonged VEGF release testifies the use of this construct as amore » scaffold for tissue-engineered vascular grafts.« less

Hyaluronic acid/Chitosan nanoparticles as delivery vehicles for VEGF and PDGF-BB.

PubMed

Parajó, Yolanda; D'Angelo, Ivana; Welle, Alexander; Garcia-Fuentes, Marcos; Alonso, María José

2010-11-01

The development of a vascular network in tissue-engineered constructs is a fundamental bottleneck of bioregenerative medicine, particularly when the size of the implant exceeds a certain limit given by diffusion lengths and/or if the host tissue shows a very active metabolism. One of the approaches to achieve the vascularization of tissue constructs is generating a sustained release of proangiogenic factors from the ischemic site. This work describes the formation and characterization of hyaluronic acid-chitosan (HA/CS) nanoparticles for the delivery of two pro-angiogenic growth factors: vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF-BB). These nanoparticles were prepared by an ionic gelification technique, and different formulations were developed by encapsulating the growth factors in association with two stabilizing agents: bovine serum albumin or heparin sodium salt. These carriers were characterized with regard to their physicochemical properties, their stability in biological media, and their cytotoxicity in the C3a hepatoma cell line. The results show that nanoparticles around 200 nm can be prepared by this method. HA/CS nanoparticles were stable when incubated in EMEM cell culture medium or in water at 37°C for 24 h. Cell culture tests confirmed that HA/CS nanoparticles are not cytotoxic within the concentration range used for growth factor delivery. Moreover, HA/CS nanoparticles were able to entrap efficiently both growth factors, reaching association values of 94% and 54% for VEGF and PDGF, respectively. In vitro release studies confirm that PDGF-BB is released from HA/CS nanoparticles in a sustained manner over approximately 1 week. On the other hand, VEGF is completely released within the first 24 h.

Development of PLGA-coated β-TCP scaffolds containing VEGF for bone tissue engineering.

PubMed

Khojasteh, Arash; Fahimipour, Farahnaz; Eslaminejad, Mohamadreza Baghaban; Jafarian, Mohammad; Jahangir, Shahrbanoo; Bastami, Farshid; Tahriri, Mohammadreza; Karkhaneh, Akbar; Tayebi, Lobat

2016-12-01

Bone tissue engineering is sought to apply strategies for bone defects healing without limitations and short-comings of using either bone autografts or allografts and xenografts. The aim of this study was to fabricate a thin layer poly(lactic-co-glycolic) acid (PLGA) coated beta-tricalcium phosphate (β-TCP) scaffold with sustained release of vascular endothelial growth factor (VEGF). PLGA coating increased compressive strength of the β-TCP scaffolds significantly. For in vitro evaluations, canine mesenchymal stem cells (cMSCs) and canine endothelial progenitor cells (cEPCs) were isolated and characterized. Cell proliferation and attachment were demonstrated and the rate of cells proliferation on the VEGF released scaffold was significantly more than compared to the scaffolds with no VEGF loading. A significant increase in expression of COL1 and RUNX2 was indicated in the scaffolds loaded with VEGF and MSCs compared to the other groups. Consequently, PLGA coated β-TCP scaffold with sustained and localized release of VEGF showed favourable results for bone regeneration in vitro, and this scaffold has the potential to use as a drug delivery device in the future. Copyright © 2016. Published by Elsevier B.V.

Arsenite induces endothelial cell permeability increase through a reactive oxygen species-vascular endothelial growth factor pathway.

PubMed

Bao, Lingzhi; Shi, Honglian

2010-11-15

As a potent environmental oxidative stressor, arsenic exposure has been reported to exacerbate cardiovascular diseases and increase vascular endothelial cell monolayer permeability. However, the underlying mechanism of this effect is not well understood. In this paper, we test our hypothesis that reactive oxygen species (ROS)-induced vascular endothelial growth factor (VEGF) expression may play an important role in an arsenic-caused increase of endothelial cell monolayer permeability. The mouse brain vascular endothelial cell bEnd3 monolayer was exposed to arsenite for 1, 3, and 6 days. The monolayer permeability, VEGF protein release, and ROS generation were determined. In addition, VE-cadherin and zonula occludens-1 (ZO-1), two membrane structure proteins, were immunostained to elucidate the effects of arsenite on the cell-cell junction. The roles of ROS and VEGF in arsenite-induced permeability was determined by inhibiting ROS with antioxidants and immuno-depleting VEGF with a VEGF antibody. We observed that arsenite increased bEnd3 monolayer permeability, elevated the production of cellular ROS, and increased VEGF release. VE-cadherin and ZO-1 disruptions were also found in cells treated with arsenite. Furthermore, both antioxidant (N-acetyl cysteine and tempol) and the VEGF antibody treatments significantly lowered the arsenite-induced permeability of the bEnd3 monolayer as well as VEGF expression. VE-cadherin and ZO-1 disruptions were also diminished by N-acetyl cysteine and the VEGF antibody. Our data suggest that the increase in VEGF expression caused by ROS may play an important role in the arsenite-induced increase in endothelial cell permeability.

The Phosphorylation of Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) by Engineered Surfaces with Electrostatically or Covalently Immobilized VEGF

PubMed Central

Anderson, Sean M.; Chen, Tom T.; Iruela-Arispe, M. Luisa; Segura, Tatiana

2010-01-01

Growth factors are a class of signaling proteins that direct cell fate through interaction with cell surface receptors. Although a myriad of possible cell fates stem from a growth factor binding to its receptor, the signaling cascades that result in one fate over another are still being elucidated. One possible mechanism by which nature modulates growth factor signaling is through the method of presentation of the growth factor – soluble or immobilized (matrix bound). Here we present the methodology to study signaling of soluble versus immobilized VEGF through VEGFR-2. We have designed a strategy to covalently immobilize VEGF using its heparin-binding domain to orient the molecule (bind) and a secondary functional group to mediate covalent binding (lock). This bind-and-lock approach aims to allow VEGF to assume a bioactive orientation before covalent immobilization. Surface plasmon resonance (SPR) demonstrated heparin and VEGF binding with surface densities of 60 ng/cm2 and 100 pg/cm2, respectively. ELISA experiments confirmed VEGF surface density and showed that electrostatically bound VEGF releases in cell medium and heparin solutions while covalently bound VEGF remains immobilized. Electrostatically bound VEGF and covalently bound VEGF phosphorylate VEGFR-2 in both VEGFR-2 transfected cells and VEGFR-2 endogenously producing cells. HUVECs plated on VEGF functionalized surfaces showed different morphologies between surface-bound VEGF and soluble VEGF. The surfaces synthesized in these studies allow for the study of VEGF/VEGFR-2 signaling induced by covalently bound, electrostatically bound, and soluble VEGF and may provide further insight into the design of materials for the generation of a mature and stable vasculature. PMID:19540581

Sustained delivery of VEGF from designer self-assembling peptides improves cardiac function after myocardial infarction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Hai-dong; Cui, Guo-hong; Yang, Jia-jun

Highlights: Black-Right-Pointing-Pointer The designer peptide LRKKLGKA could self-assemble into nanofibers. Black-Right-Pointing-Pointer Injection of LRKKLGKA peptides could promote the sustained delivery of VEGF. Black-Right-Pointing-Pointer Injection of VEGF with LRKKLGKA peptides lead to sufficient angiogenesis. Black-Right-Pointing-Pointer Injection of VEGF with LRKKLGKA peptides improves heart function. -- Abstract: Poor vascularization and insufficient oxygen supply are detrimental to the survival of residual cardiomyocytes or transplanted stem cells after myocardial infarction. To prolong and slow the release of angiogenic factors, which stimulate both angiogenesis and vasculogenesis, we constructed a novel self-assembling peptide by attaching the heparin-binding domain sequence LRKKLGKA to the self-assembling peptide RADA16. Thismore » designer self-assembling peptide self-assembled into nanofiber scaffolds under physiological conditions, as observed by atomic force microscopy. The injection of designer self-assembling peptides can efficiently provide the sustained delivery of VEGF for at least 1 month. At 4 weeks after transplantation, cardiac function was improved, and scar size and collagen deposition were markedly reduced in the group receiving VEGF with the LRKKLGKA scaffolds compared with groups receiving VEGF alone, LRKKLGKA scaffolds alone or VEGF with RADA16 scaffolds. The microvessel density in the VEGF with LRKKLGKA group was higher than that in the VEGF with RADA16 group. TUNEL and cleaved caspase-3 expression assays showed that the transplantation of VEGF with LRKKLGKA enhanced cell survival in the infarcted heart. These results present the tailor-made peptide scaffolds as a new generation of sustained-release biomimetic biomaterials and suggest that the use of angiogenic factors along with designer self-assembling peptides can lead to myocardial protection, sufficient angiogenesis, and improvement in cardiac function.« less

HSV-mediated gene transfer of vascular endothelial growth factor to dorsal root ganglia prevents diabetic neuropathy

PubMed Central

Chattopadhyay, M; Krisky, D; Wolfe, D; Glorioso, JC; Mata, M; Fink, DJ

2005-01-01

We examined the utility of herpes simplex virus (HSV) vector-mediated gene transfer of vascular endothelial growth factor (VEGF) in a mouse model of diabetic neuropathy. A replication-incompetent HSV vector with VEGF under the control of the HSV ICP0 promoter (vector T0VEGF) was constructed. T0VEGF expressed and released VEGF from primary dorsal root ganglion (DRG) neurons in vitro, and following subcutaneous inoculation in the foot, expressed VEGF in DRG and nerve in vivo. At 2 weeks after induction of diabetes, subcutaneous inoculation of T0VEGF prevented the reduction in sensory nerve amplitude characteristic of diabetic neuropathy measured 4 weeks later, preserved autonomic function measured by pilocarpine-induced sweating, and prevented the loss of nerve fibers in the skin and reduction of neuropeptide calcitonin gene-related peptide and substance P in DRG neurons of the diabetic mice. HSV-mediated transfer of VEGF to DRG may prove useful in treatment of diabetic neuropathy. PMID:15843809

Effects of VEGF-ANG-1-PLA nano-sustained release microspheres on proliferation and differentiation of ADSCs.

PubMed

He, Yucang; Li, Zihao; Chen, Zhuojie; Yu, Xiaofang; Ji, Ziwan; Wang, Jingping; Qian, Yao; Li, Liqun

2018-05-10

The improvement of fat graft viability might depend on the presence of multipotent resident adipose derived stem cells (ADSCs) which is the important component of stromal vascular fraction (SVF). Vascular endothelial growth factor (VEGF) and angiogenin-1 (Ang-1) are responsible for neovascularization. However, their half-life is too short to produce a biological effect. We thus investigated whether VEGF-ANG-1-polylactic acid (PLA) microspheres could enhance the angiogenic properties of ADSCs. PLA microspheres containing VEGF and ANG-1 were prepared by in vitro ultrasonic emulsification and characterized according to their encapsulation efficiency (EE), drug-loading rate (DL), particle size and drug release. The systemic toxicity of empty loaded nanospheres (NPs) and the ability of these microspheres to promote the proliferation and differentiation of ADSCs were evaluated. The EE and DL were above 86% and 2.8%, respectively. The drug release was completed after 20 days. Systemic toxicity was verified in ADSCs that received the unloaded NPs. It was observed that ADSCs treated with VEGF-ANG-1-PLA microspheres had an increase in the proliferation and the number of CD31 positive cells. ADSCs proliferation and differentiation toward endothelial cells (ECs) could be enhanced by the addition of VEGF-ANG-1-PLA nano-sustained release microspheres. This article is protected by copyright. All rights reserved.

Connective tissue growth factor is a substrate of ADAM28

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mochizuki, Satsuki; Tanaka, Rena; Shimoda, Masayuki

2010-11-26

Research highlights: {yields} The hyper-variable region in the cysteine-rich domain of ADAM28 binds to C-terminal domain of CTGF. {yields} ADAM28 cleaves CTGF alone and CTGF in the CTGF/VEGF{sub 165} complex. {yields} CTGF digestion by ADAM28 releases biologically active VEGF{sub 165} from the complex. {yields} ADAM28, CTGF and VEGF{sub 165} are commonly co-expressed by carcinoma cells in human breast carcinoma tissues. {yields} These suggest that ADAM28 promotes VEGF{sub 165}-induced angiogenesis in the breast carcinomas by selective CTGF digestion in the CTGF/VEGF{sub 165} complex. -- Abstract: ADAM28, a member of the ADAM (a disintegrin and metalloproteinase) gene family, is over-expressed by carcinomamore » cells and the expression correlates with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, information about substrates of ADAM28 is limited. We screened interacting molecules of ADAM28 in human lung cDNA library by yeast two-hybrid system and identified connective tissue growth factor (CTGF). Binding of CTGF to proADAM28 was demonstrated by yeast two-hybrid assay and protein binding assay. ADAM28 cleaved CTGF in dose- and time-dependent manners at the Ala{sup 181}-Tyr{sup 182} and Asp{sup 191}-Pro{sup 192} bonds in the hinge region of the molecule. ADAM28 selectively digested CTGF in the complex of CTGF and vascular endothelial growth factor{sub 165} (VEGF{sub 165}), releasing biologically active VEGF{sub 165} from the complex. RT-PCR and immunohistochemical analyses demonstrated that ADAM28, CTGF and VEGF are commonly co-expressed in the breast carcinoma tissues. These data provide the first evidence that CTGF is a novel substrate of ADAM28 and suggest that ADAM28 may promote VEGF{sub 165}-induced angiogenesis in the breast carcinomas by the CTGF digestion in the CTGF/VEGF{sub 165} complex.« less

The use of injectable sonication-induced silk hydrogel for VEGF165 and BMP-2 delivery for elevation of the maxillary sinus floor

PubMed Central

Zhang, Wenjie; Wang, Xiuli; Wang, Shaoyi; Zhao, Jun; Xu, Lianyi; Zhu, Chao; Zeng, Deliang; Chen, Jake; Zhang, Zhiyuan; Kaplan, David L.; Jiang, Xinquan

2011-01-01

Sonication-induced silk hydrogels were previously prepared as an injectable bone replacement biomaterial, with a need to improve osteogenic features. Vascular endothelial growth factor (VEGF165) and bone morphogenic protein-2 (BMP-2) are key regulators of angiogenesis and osteogenesis, respectively, during bone regeneration. Therefore, the present study aimed at evaluating in situ forming silk hydrogels as a vehicle to encapsulate dual factors for rabbit maxillary sinus floor augmentation. Sonication-induced silk hydrogels were prepared in vitro and the slow release of VEGF165 and BMP-2 from these silk gels was evaluated by ELISA. For in vivo studies for each time point (4 and 12 weeks), 24 sinus floors elevation surgeries were made bilaterally in 12 rabbits for the following four treatment groups: silk gel (group Silk gel), silk gel/VEGF165 (group VEGF), silk gel/BMP-2 (group BMP-2), silk gel/VEGF165/BMP-2 (group V+B) (n=6 per group). Sequential florescent labeling and radiographic observations were used to record new bone formation and mineralization, along with histological and histomorphometric analysis. At week 4, VEGF165 promoted more tissue infiltration into the gel and accelerated the degradation of the gel material. At this time point, the bone area in group V+B was significantly larger than those in the other three groups. At week 12, elevated sinus floor heights of groups BMP-2 and V+B were larger than those of the Silk gel and VEGF groups, and the V+B group had the largest new bone area among all groups. In addition, a larger blood vessel area formed in the remaining gel areas in groups VEGF and V+B. In conclusion, VEGF165 and BMP-2 released from injectable and biodegradable silk gels promoted angiogenesis and new bone formation, with the two factors demonstrating an additive effect on bone regeneration. These results indicate that silk hydrogels can be used as an injectable vehicle to deliver multiple growth factors in a minimally invasive approach to regenerate irregular bony cavities. PMID:21889205

Dimethyl sulfoxide-caused changes in pro- and anti-angiogenic factor levels could contribute to an anti-angiogenic response in HeLa cells.

PubMed

Şimşek, Ece; Aydemir, Esra Arslan; İmir, Nilüfer; Koçak, Orhan; Kuruoğlu, Aykut; Fışkın, Kayahan

2015-10-01

Dimethyl sulfoxide (DMSO) is widely used in biological research as a general solvent. While it has been previously demonstrated that DMSO possesses a wide range of pharmacological effects, there is no published work regarding the effects of DMSO on pro-angiogenic factor levels. This study was designed to investigate the possible effects of DMSO on the levels of three pro-angiogenic factors released from HeLa cells in vitro. Cells were treated with two different and previously determined concentrations of DMSO. The cytotoxic effects of DMSO concentrations on HeLa cells were determined via MTT. Survival rates of DMSO-treated cells were determined by Invitrogen live/dead viability/cytotoxicity kit and trypan blue exclusion assay. Changes in the pro-angiogenic levels in media were evaluated by Cayman's Substance P Enzyme Immunoassay ELISA kit. Vascular endothelial growth factor ELISA kit and interferon gamma ELISA kit for substance P, VEGF and IFNγ respectively. Changes in substance P levels were corrected by standard western blotting. Changes in VEGF and IFNγ levels were corrected both by western blot and real time PCR. Treatment with 1.4 μM DMSO caused a time-dependent inhibition of cell proliferation at 24, 48 and 72 h. 1.4 μM DMSO caused a significant reduction in VEGF levels at 72 h of incubation and sharp increases in IFNγ levels at both 48 and 72 h of incubation. According to real time PCR analyses, DMSO (1.4 μM) exhibited an inhibitory effect on VEGF but acted as an augmenter of IFNγ release on HeLa cells in vitro. This is the first report showing that the general solvent DMSO suppressed HeLa cell proliferation, decreased the levels of two pro-angiogenic factors (substance P and VEGF) and increased the release of an anti-angiogenic factor IFNγ in vitro. Copyright © 2015 Elsevier Ltd. All rights reserved.

* Central Growth Factor Loaded Depots in Bone Tissue Engineering Scaffolds for Enhanced Cell Attraction.

PubMed

Quade, Mandy; Knaack, Sven; Akkineni, Ashwini Rahul; Gabrielyan, Anastasia; Lode, Anja; Rösen-Wolff, Angela; Gelinsky, Michael

2017-08-01

Tissue engineering, the application of stem and progenitor cells in combination with an engineered extracellular matrix, is a promising strategy for bone regeneration. However, its success is limited by the lack of vascularization after implantation. The concept of in situ tissue engineering envisages the recruitment of cells necessary for tissue regeneration from the host environment foregoing ex vivo cell seeding of the scaffold. In this study, we developed a novel scaffold system for enhanced cell attraction, which is based on biomimetic mineralized collagen scaffolds equipped with a central biopolymer depot loaded with chemotactic agents. In humid milieu, as after implantation, the signaling factors are expected to slowly diffuse out of the central depot forming a gradient that stimulates directed cell migration toward the scaffold center. Heparin, hyaluronic acid, and alginate have been shown to be capable of depot formation. By using vascular endothelial growth factor (VEGF) as model factor, it was demonstrated that the release kinetics can be adjusted by varying the depot composition. While alginate and hyaluronic acid are able to reduce the initial burst and prolong the release of VEGF, the addition of heparin led to a much stronger retention that resulted in an almost linear release over 28 days. The biological activity of released VEGF was proven for all variants using an endothelial cell proliferation assay. Furthermore, migration experiments with endothelial cells revealed a relationship between the degree of VEGF retention and migration distance: cells invaded deepest in scaffolds containing a heparin-based depot indicating that the formation of a steep gradient is crucial for cell attraction. In conclusion, this novel in situ tissue engineering approach, specifically designed to recruit and accommodate endogenous cells upon implantation, appeared highly promising to stimulate cell invasion, which in turn would promote vascularization and finally new bone formation.

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion.

PubMed

Gorin, Caroline; Rochefort, Gael Y; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Muller, Laurent; Chaussain, Catherine; Germain, Stéphane

2016-03-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. ©AlphaMed Press.

In vitro effects of 0 to 120 Grays of irradiation on bone viability and release of growth factors.

PubMed

Sawada, Kosaku; Fujioka-Kobayashi, Masako; Kobayashi, Eizaburo; Brömme, Jens O; Schaller, Benoit; Miron, Richard J

2016-07-04

High dose radiation therapy is commonly used in maxillofacial surgeries to treat a number of head and neck tumors. Despite its widespread use, little information is available regarding the effects of irradiation on bone cell viability and release of growth factors following dose-dependent irradiation. Bone samples were collected from porcine mandibular cortical bone and irradiated at doses of 0, 7.5, 15, 30, 60 and 120 Grays. Thereafter, cell viability was quantified, and the release of growth factors including TGFβ1, BMP2, VEGF, IL1β and RANKL were investigated over time. It was observed that at only 7.5Gy of irradiation, over 85 % of cells were non-vital and by 60 Gy, all cells underwent apoptosis. Furthermore, over a 7-fold decrease in VEGF and a 2-fold decrease in TGFβ1 were observed following irradiation at all tested doses. Little change was observed for BMP2 and IL1β whereas RANKL was significantly increased for all irradiated samples. These results demonstrate the pronounced effects of irradiation on bone-cell vitality and subsequent release of growth factors. Interestingly, the largest observed change in gene expression was the 7-fold decrease in VEGF protein following irradiation. Future research aimed at improving our understanding of bone following irradiation is necessary to further improve future clinical treatments.

The mechanisms how heparin affects the tumor cell induced VEGF and chemokine release from platelets to attenuate the early metastatic niche formation

PubMed Central

Ponert, Jan Moritz; Schwarz, Svenja; Haschemi, Reza; Müller, Jens; Pötzsch, Bernd; Bendas, Gerd

2018-01-01

Metastasis is responsible for the majority of cancer associated fatalities. Tumor cells leaving the primary tumor and entering the blood flow immediately interact with platelets. Activated platelets contribute in different ways to cancer cell survival and proliferation, e.g. in formation of the early metastatic niche by release of different growth factors and chemokines. Here we show that a direct interaction between platelets and MV3 melanoma or MCF7 breast cancer cells induces platelet activation and a VEGF release in citrated plasma that cannot be further elevated by the coagulation cascade and generated thrombin. In contrast, the release of platelet-derived chemokines CXCL5 and CXCL7 depends on both, a thrombin-mediated platelet activation and a direct interaction between tumor cells and platelets. Preincubation of platelets with therapeutic concentrations of unfractionated heparin reduces the tumor cell initiated VEGF release from platelets. In contrast, tumor cell induced CXCL5 and CXCL7 release from platelets was not impacted by heparin pretreatment in citrated plasma. In defibrinated, recalcified plasma, on the contrary, heparin is able to reduce CXCL5 and CXCL7 release from platelets by thrombin inhibition. Our data indicate that different chemokines and growth factors in diverse platelet granules are released in tightly regulated processes by various trigger mechanisms. We show for the first time that heparin is able to reduce the mediator release induced by different tumor cells both in a contact and coagulation dependent manner. PMID:29346400

Tumor acidity-activatable manganese phosphate nanoplatform for amplification of photodynamic cancer therapy and magnetic resonance imaging.

PubMed

Hao, Yongwei; Zheng, Cuixia; Wang, Lei; Zhang, Jinjie; Niu, Xiuxiu; Song, Qingling; Feng, Qianhua; Zhao, Hongjuan; Li, Li; Zhang, Hongling; Zhang, Zhenzhong; Zhang, Yun

2017-10-15

Amorphous biodegradable metal phosphate nanomaterials are considered to possess great potential in cancer theranostic application due to their promise in providing ultra-sensitive pH-responsive therapeutic benefits and diagnostic functions simultaneously. Here we report the synthesis of photosensitising and acriflavine-carrying amorphous porous manganese phosphate (PMP) nanoparticles with ultra-sensitive pH-responsive degradability and their application for a photoactivable synergistic nanosystem that imparts reactive oxygen species (ROS) induced cytotoxicity in synchrony with hypoxia-inducible factor 1α/vascular endothelial growth factor (HIF1α/VEGF) inhibitor that suppresses tumor growth and treatment escape signalling pathway. Carboxymethyl dextran (CMD) is chemically anchored on the surface of porous manganese phosphate theranostic system through the pH-responsive boronate esters. Upon the stimulus of the tumor acid microenvironment, manganese phosphate disintegrates and releases Mn 2+ ions rapidly, which are responsible for the magnetic resonance imaging (MRI) effect. Meanwhile, the released photosensitizer chlorin e6 (Ce6) produces ROS under irradiation while acriflavine (ACF) inhibits the HIF-1α/VEGF pathway during the burst release of VEGF in tumour induced by photodynamic therapy (PDT), resulting in increased therapeutic efficacy. Considering the strong pH responsivity, MRI signal amplification and drug release profile, the PMP nanoparticles offer new prospects for tumor acidity-activatable theranostic application by amplifying the PDT through inhibiting the HIF-1α /VEGF pathway timely while enhancing the MRI effect. In this study, we report the synthesis of the tumor acidity-activatable amorphous porous manganese phosphate nanoparticles and their application for a photoactivable synergistic nanosystem that imparts reactive oxygen species (ROS) induced cytotoxicity in synchrony with hypoxia-inducible factor 1α/vascular endothelial growth factor (HIF-1α/VEGF) inhibitor that suppresses tumor growth and treatment escape signalling pathway. Besides, upon the stimulus of the tumor acid microenvironment, the manganese phosphate nanoparticles finally disintegrate and release Mn 2+ ions rapidly, which are responsible for the magnetic resonance imaging (MRI) effect. This nanoplatform is featured with distinctive advantages such as ultra pH-responsive drug release, MRI function and rational drug combination exploiting the blockage of the treatment escape signalling pathway. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

VEGF-induced neoangiogenesis is mediated by NAADP and two-pore channel-2–dependent Ca2+ signaling

PubMed Central

Favia, Annarita; Desideri, Marianna; Gambara, Guido; D’Alessio, Alessio; Ruas, Margarida; Esposito, Bianca; Del Bufalo, Donatella; Parrington, John; Ziparo, Elio; Palombi, Fioretta; Galione, Antony; Filippini, Antonio

2014-01-01

Vascular endothelial growth factor (VEGF) and its receptors VEGFR1/VEGFR2 play major roles in controlling angiogenesis, including vascularization of solid tumors. Here we describe a specific Ca2+ signaling pathway linked to the VEGFR2 receptor subtype, controlling the critical angiogenic responses of endothelial cells (ECs) to VEGF. Key steps of this pathway are the involvement of the potent Ca2+ mobilizing messenger, nicotinic acid adenine-dinucleotide phosphate (NAADP), and the specific engagement of the two-pore channel TPC2 subtype on acidic intracellular Ca2+ stores, resulting in Ca2+ release and angiogenic responses. Targeting this intracellular pathway pharmacologically using the NAADP antagonist Ned-19 or genetically using Tpcn2−/− mice was found to inhibit angiogenic responses to VEGF in vitro and in vivo. In human umbilical vein endothelial cells (HUVECs) Ned-19 abolished VEGF-induced Ca2+ release, impairing phosphorylation of ERK1/2, Akt, eNOS, JNK, cell proliferation, cell migration, and capillary-like tube formation. Interestingly, Tpcn2 shRNA treatment abolished VEGF-induced Ca2+ release and capillary-like tube formation. Importantly, in vivo VEGF-induced vessel formation in matrigel plugs in mice was abolished by Ned-19 and, most notably, failed to occur in Tpcn2−/− mice, but was unaffected in Tpcn1−/− animals. These results demonstrate that a VEGFR2/NAADP/TPC2/Ca2+ signaling pathway is critical for VEGF-induced angiogenesis in vitro and in vivo. Given that VEGF can elicit both pro- and antiangiogenic responses depending upon the balance of signal transduction pathways activated, targeting specific VEGFR2 downstream signaling pathways could modify this balance, potentially leading to more finely tailored therapeutic strategies. PMID:25331892

Cytotoxic T lymphocyte-dependent tumor growth inhibition by a vascular endothelial growth factor-superantigen conjugate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Qingwen; State Key Laboratory of Genetic Engineering, Fudan University, Shanghai 200433; Jiang, Songmin

2012-11-02

Highlights: Black-Right-Pointing-Pointer We construct and purify a fusion protein VEGF-SEA. Black-Right-Pointing-Pointer VEGF-SEA strongly repressed the growth of murine solid sarcoma 180 (S180) tumors. Black-Right-Pointing-Pointer T cells driven by VEGF-SEA were accumulated around tumor cells bearing VEGFR by mice image model. Black-Right-Pointing-Pointer VEGF-SEA can serve as a tumor targeting agent and sequester CTLs into the tumor site. Black-Right-Pointing-Pointer The induced CTLs could release the cytokines, perforins and granzyme B to kill the tumor cells. -- Abstract: T cells are major lymphocytes in the blood and passengers across the tumor vasculature. If these T cells are retained in the tumor site, amore » therapeutic potential will be gained by turning them into tumor-reactive cytotoxic T lymphocytes (CTLs). A fusion protein composed of human vascular endothelial growth factor (VEGF) and staphylococcal enterotoxin A (SEA) with a D227A mutation strongly repressed the growth of murine solid sarcoma 180 (S180) tumors (control versus VEGF-SEA treated with 15 {mu}g, mean tumor weight: 1.128 g versus 0.252 g, difference = 0.876 g). CD4{sup +} and CD8{sup +} T cells driven by VEGF-SEA were accumulated around VEGFR expressing tumor cells and the induced CTLs could release the tumoricidal cytokines, such as interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha). Meanwhile, intratumoral CTLs secreted cytolytic pore-forming perforin and granzyme B proteins around tumor cells, leading to the death of tumor cells. The labeled fusion proteins were gradually targeted to the tumor site in an imaging mice model. These results show that VEGF-SEA can serve as a tumor targeting agent and sequester active infiltrating CTLs into the tumor site to kill tumor cells, and could therefore be a potential therapeutical drug for a variety of cancers.« less

Streptococcus sanguinis-induced cytokine and matrix metalloproteinase-1 release from platelets.

PubMed

Cognasse, Fabrice; Hamzeh-Cognasse, Hind; Chabert, Adrien; Jackson, Elke; Arthaud, Charles-Antoine; Garraud, Olivier; McNicol, Archie

2014-04-22

Streptococcus sanguinis (S.sanguinis), a predominant bacterium in the human oral cavity, has been widely associated with the development of infective endocarditis. Platelets play both a haemostatic function and can influence both innate and adaptive immune responses. Previous studies have shown that S.sanguinis can interact with, and activate, platelets. The aim of this study was to determine whether S.sanguinis stimulates the release of matrix metalloproteinases (MMPs) 1, 2 and 9 and the pro-inflammatory mediators SDF-1, VEGF and sCD40L, from platelets and to subsequently pharmacologically address the release mechanism (s). S.sanguinis stimulated the release of MMP-1, SDF-1, VEGF and sCD40L from platelets and inhibitors of cyclooxygenase and phosphatidylinositol 3-kinase, and antagonists of the αIIbβ3 integrin and glycoprotein Ib, each inhibited the secretion of all factors. Therefore the release of MMP-1, SDF-1, VEGF and sCD40L occurs late in the platelet response to S.sanguinis and highlights the complex intracellular signalling pathways stimulated in response to S.sanguinis which lead to haemostasis, MMP and pro-inflammatory mediator secretion.

Interleukin-6 and vascular endothelial growth factor release by renal cell carcinoma cells impedes lymphocyte-dendritic cell cross-talk.

PubMed

Cabillic, F; Bouet-Toussaint, F; Toutirais, O; Rioux-Leclercq, N; Fergelot, P; de la Pintière, C Thomas; Genetet, N; Patard, J-J; Catros-Quemener, V

2006-12-01

Anti-tumour T cell response requires antigen presentation via efficient immunological synapse between antigen presenting cells, e.g. dendritic cells (DC), and specific T cells in an adapted Th1 cytokine context. Nine renal cell carcinoma (RCC) primary culture cells were used as sources of tumour antigens which were loaded on DC (DC-Tu) for autologous T cell activation assays. Cytotoxic activity of lymphocytes stimulated with DC-Tu was evaluated against autologous tumour cells. Assays were performed with 75 grays irradiated tumour cells (Tu irr) and with hydrogen peroxide +/- heat shock (Tu H(2)O(2) +/- HS) treated cells. DC-Tu irr failed to enhance cytotoxic activity of autologous lymphocytes in seven of 13 assays. In all these defective assays, irradiated tumour cells displayed high interleukin (IL)-6 and vascular endothelial growth factor (VEGF) release. Conversely, when tumour cells released low IL-6 levels (n = 4), DC-Tu irr efficiently enhanced CTL activity. When assays were performed with the same RCC cells treated with H(2)O(2) + HS, DC-Tu stimulation resulted in improved CTL activity. H(2)O(2) + HS treatment induced post-apoptotic cell necrosis of tumour cells, totally abrogated their cytokine release [IL-6, VEGF, transforming growth factor (TGF)-beta1] and induced HSP70 expression. Taken together, data show that reduction in IL-6 and VEGF release in the environment of the tumour concomitantly to tumour cell HSP expression favours induction of a stronger anti-tumour CTL response.

Activation of platelet-rich plasma using soluble type I collagen.

PubMed

Fufa, Duretti; Shealy, Blake; Jacobson, May; Kevy, Sherwin; Murray, Martha M

2008-04-01

Platelet-rich plasma (PRP) has recently been found to be a useful delivery system for growth factors important to oral tissue healing. But application of PRP in a liquid form to a wound site within the oral cavity can be complicated by significant loss of the PRP into the surrounding oral space unless gelation through the clotting mechanism is accomplished. Gelation is currently accomplished using bovine thrombin; however, rare but serious complications of this method have led to the search for alternative clotting mechanisms, including the use of soluble collagen as a clotting activator. In this work, our hypothesis was that soluble type I collagen would be as effective as bovine thrombin in causing clotting of the PRP and stimulating growth factor release from the platelets and granulocytes. PRP from human donors was clotted using type I collagen or bovine thrombin. Clot retraction was determined by measuring clot diameters over time. The release of platelet-derived growth factor (PDGF)-AB, transforming growth factor (TGF)-beta1, and vascular endothelial growth factor (VEGF) from both types of clots was measured over 10 days using enzyme-linked immunosorbent assasy. Clots formed using type I collagen exhibited far less retraction than those formed with bovine thrombin. Bovine thrombin and type I collagen stimulated similar release of PDGF-AB and VEGF between 1 and 10 days; however, thrombin activation resulted in a greater release of TGF-beta1 during the first 5 days after activation. The use of type I collagen to activate clotting of PRP may be a safe and effective alternative to bovine thrombin. The use of collagen results in less clot retraction and equal release of PDGF-AB and VEGF compared with currently available methods of clot activation.

Nanodiamond-based injectable hydrogel for sustained growth factor release: Preparation, characterization and in vitro analysis.

PubMed

Pacelli, Settimio; Acosta, Francisca; Chakravarti, Aparna R; Samanta, Saheli G; Whitlow, Jonathan; Modaresi, Saman; Ahmed, Rafeeq P H; Rajasingh, Johnson; Paul, Arghya

2017-08-01

Nanodiamonds (NDs) represent an emerging class of carbon nanomaterials that possess favorable physical and chemical properties to be used as multifunctional carriers for a variety of bioactive molecules. Here we report the synthesis and characterization of a new injectable ND-based nanocomposite hydrogel which facilitates a controlled release of therapeutic molecules for regenerative applications. In particular, we have formulated a thermosensitive hydrogel using gelatin, chitosan and NDs that provides a sustained release of exogenous human vascular endothelial growth factor (VEGF) for wound healing applications. Addition of NDs improved the mechanical properties of the injectable hydrogels without affecting its thermosensitive gelation properties. Biocompatibility of the generated hydrogel was verified by in vitro assessment of apoptotic gene expressions and anti-inflammatory interleukin productions. NDs were complexed with VEGF and the inclusion of this complex in the hydrogel network enabled the sustained release of the angiogenic growth factor. These results suggest for the first time that NDs can be used to formulate a biocompatible, thermosensitive and multifunctional hydrogel platform that can function both as a filling agent to modulate hydrogel properties, as well as a delivery platform for the controlled release of bioactive molecules and growth factors. One of the major drawbacks associated with the use of conventional hydrogels as carriers of growth factors is their inability to control the release kinetics of the loaded molecules. In fact, in most cases, a burst release is inevitable leading to diminished therapeutic effects and unsuccessful therapies. As a potential solution to this issue, we hereby propose a strategy of incorporating ND complexes within an injectable hydrogel matrix. The functional groups on the surface of the NDs can establish interactions with the model growth factor VEGF and promote a prolonged release from the polymer network, therefore, providing a longer therapeutic effect. Our strategy demonstrates the efficacy of using NDs as an essential component for the design of a novel injectable nanocomposite system with improved release capabilities. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Systemic pretreatment with dimethyloxalylglycine increases myocardial HIF-1α and VEGF production and improves functional recovery after acute ischemia/reperfusion.

PubMed

Poynter, Jeffrey A; Manukyan, Mariuxi C; Wang, Yue; Brewster, Benjamin D; Herrmann, Jeremy L; Weil, Brent R; Abarbanell, Aaron M; Meldrum, Daniel R

2011-08-01

Stem cells protect the heart from ischemic damage in part by the release of cytoprotective growth factors, particularly vascular endothelial growth factor (VEGF). Production of VEGF is regulated in part by levels of the transcription factor hypoxia inducible factor 1-α (HIF-1α). Dimethyloxalylglycine (DMOG) prevents the deactivation of HIF-1α and increases VEGF production. However, the effects of systemic DMOG treatment on myocardial tolerance for ischemia are unknown. We hypothesized that systemic pretreatment with DMOG would improve myocardial ischemic tolerance. To study this hypothesis, adult male rats were randomly given an intraperitoneal injection of DMOG (40 mg/kg in 1 mL saline, n = 5) or saline (1 mL, n = 6) 24 h before cardiectomy and isolated heart perfusion. All hearts were subjected to 15 min equilibration, 25 min ischemia and 40 min reperfusion. Myocardial function was continuously monitored. Following reperfusion, myocardial homogenates were analyzed for HIF-1α and VEGF production. We observed that hearts in the DMOG group exhibited greater recovery of left ventricular developed pressure LVDP, +dP/dt and -dP/dt. Myocardial HIF-1α and VEGF levels were increased by DMOG therapy. In conclusion, systemic pretreatment with DMOG augments post-ischemic myocardial functional recovery through increased HIF-1α levels and greater VEGF production. Copyright © 2011 Mosby, Inc. All rights reserved.

Engineered stem cell mimics to enhance stroke recovery.

PubMed

George, Paul M; Oh, Byeongtaek; Dewi, Ruby; Hua, Thuy; Cai, Lei; Levinson, Alexa; Liang, Xibin; Krajina, Brad A; Bliss, Tonya M; Heilshorn, Sarah C; Steinberg, Gary K

2018-06-13

Currently, no medical therapies exist to augment stroke recovery. Stem cells are an intriguing treatment option being evaluated, but cell-based therapies have several challenges including developing a stable cell product with long term reproducibility. Since much of the improvement observed from cellular therapeutics is believed to result from trophic factors the stem cells release over time, biomaterials are well-positioned to deliver these important molecules in a similar fashion. Here we show that essential trophic factors secreted from stem cells can be effectively released from a multi-component hydrogel system into the post-stroke environment. Using our polymeric system to deliver VEGF-A and MMP-9, we improved recovery after stroke to an equivalent degree as observed with traditional stem cell treatment in a rodent model. While VEGF-A and MMP-9 have many unique mechanisms of action, connective tissue growth factor (CTGF) interacts with both VEGF-A and MMP-9. With our hydrogel system as well as with stem cell delivery, the CTGF pathway is shown to be downregulated with improved stroke recovery. Copyright © 2018 Elsevier Ltd. All rights reserved.

VEGF-induced intracellular Ca2+ oscillations are down-regulated and do not stimulate angiogenesis in breast cancer-derived endothelial colony forming cells

PubMed Central

Ruffinatti, Federico Alessandro; Poletto, Valentina; Massa, Margherita; Tancredi, Richard; Zuccolo, Estella; Khdar, Dlzar Alì; Riccardi, Alberto; Biggiogera, Marco; Rosti, Vittorio; Guerra, Germano; Moccia, Francesco

2017-01-01

Endothelial colony forming cells (ECFCs) represent a population of truly endothelial precursors that promote the angiogenic switch in solid tumors, such as breast cancer (BC). The intracellular Ca2+ toolkit, which drives the pro-angiogenic response to VEGF, is remodelled in tumor-associated ECFCs such that they are seemingly insensitive to this growth factor. This feature could underlie the relative failure of anti-VEGF therapies in cancer patients. Herein, we investigated whether and how VEGF uses Ca2+ signalling to control angiogenesis in BC-derived ECFCs (BC-ECFCs). Although VEGFR-2 was normally expressed, VEGF failed to induce proliferation and in vitro tubulogenesis in BC-ECFCs. Likewise, VEGF did not trigger robust Ca2+ oscillations in these cells. Similar to normal cells, VEGF-induced intracellular Ca2+ oscillations were triggered by inositol-1,4,5-trisphosphate-dependent Ca2+ release from the endoplasmic reticulum (ER) and maintained by store-operated Ca2+ entry (SOCE). However, InsP3-dependent Ca2+ release was significantly lower in BC-ECFCs due to the down-regulation of ER Ca2+ levels, while there was no remarkable difference in the amplitude, pharmacological profile and molecular composition of SOCE. Thus, the attenuation of the pro-angiogenic Ca2+ response to VEGF was seemingly due to the reduction in ER Ca2+ concentration, which prevents VEGF from triggering robust intracellular Ca2+ oscillations. However, the pharmacological inhibition of SOCE prevented BC-ECFC proliferation and in vitro tubulogenesis. These findings demonstrate for the first time that BC-ECFCs are insensitive to VEGF, which might explain at cellular and molecular levels the failure of anti-VEGF therapies in BC patients, and hint at SOCE as a novel molecular target for this disease. PMID:29221123

GENDER DIFFERENCES IN INJURY INDUCED MESENCHYMAL STEM CELL APOPTOSIS, EXPRESSION OF VEGF, TNF, AND IL-6 AND ABROGATION VIA TNFR1 ABLATION

PubMed Central

Crisostomo, Paul R.; Wang, Meijing; Herring, Christine M.; Markel, Troy A.; Meldrum, Kirstan K.; Lillemoe, Keith D.; Meldrum, Daniel R.

2007-01-01

Concomitant pro- and anti-inflammatory properties of bone marrow stem cells (BMSC) may be an important aspect of their ability to heal injured tissue. However, very few studies have examined whether gender differences exist in BMSC function. Indeed, it remains unknown whether gender differences exist in BMSC function and ability to resist apoptosis, and if so, whether TNF receptor 1 (TNFR1) plays a role in these differences. We hypothesized that TNFR1 ablation equalizes gender differences in bone marrow mesenchymal stem cell (MSC) apoptosis, as well as expression of vascular endothelial growth factor (VEGF), TNF, and interleukin (IL)-6. Mouse MSCs from male wildtype (WT), female WT, male TNFR1 knockouts (TNFR1KO), and female TNFR1KO were stressed by endotoxin 200 ng/ml or 1 hr hypoxia. MSC activation was determined by measuring VEGF, TNF, and IL-6 production (ELISA). Differences considered significant if p<0.05. LPS and hypoxia resulted in significant activation in all experimental groups compared to controls. Male WT demonstrated significantly greater TNF and IL-6 and significantly less VEGF release than female WT MSCs. However, release of TNF, IL-6, and VEGF in male TNFR1 knockouts differed from male WT, but was not different from female WT MSCs. Similarly apoptosis in hypoxic male TNFRIKO differed from male WT, but it was not different from apoptosis from WT female. Female WT did not differ in TNF, IL-6, and VEGF release compared to female TNFR1KO. Gender differences exist in injury induced BMSC VEGF, TNF, and IL-6 expression. TNFR1 may autoregulate VEGF, TNF, and IL-6 expression in males more than females. MSCs are novel therapeutic agents for organ protection, but further study of the disparate expression of VEGF, TNF, and IL-6 in males and females as well as the role of TNFR1 in these gender differences is necessary to maximize this protection. PMID:17070836

Multifunctional silk-heparin biomaterials for vascular tissue engineering applications

PubMed Central

Seib, F. Philipp; Herklotz, Manuela; Burke, Kelly A.; Maitz, Manfred F.; Werner, Carsten; Kaplan, David L.

2013-01-01

Over the past 30 years, silk has been proposed for numerous biomedical applications that go beyond its traditional use as a suture material. Silk sutures are well tolerated in humans, but the use of silk for vascular engineering applications still requires extensive biocompatibility testing. Some studies have indicated a need to modify silk to yield a hemocompatible surface. This study examined the potential of low molecular weight heparin as a material for refining silk properties by acting as a carrier for vascular endothelial growth factor (VEGF) and improving silk hemocompatibility. Heparinized silk showed a controlled VEGF release over 6 days; the released VEGF was bioactive and supported the growth of human endothelial cells. Silk samples were then assessed using a humanized hemocompatibility system that employs whole blood and endothelial cells. The overall thrombogenic response for silk was very low and similar to the clinical reference material polytetrafluoroethylene. Despite an initial inflammatory response to silk, apparent as complement and leukocyte activation, the endothelium was maintained in a resting, anticoagulant state. The low thrombogenic response and the ability to control VEGF release support the further development of silk for vascular applications. PMID:24099708

The synergistic effect of VEGF and biomorphic silicon carbides topography on in vivo angiogenesis and human bone marrow derived mesenchymal stem cell differentiation.

PubMed

Díaz-Rodríguez, P; Gómez-Amoza, J L; Landin, M

2015-08-04

Topographical features of biomaterials are able to modulate cell attachment, spreading and differentiation. The addition of growth factors to implantable biomaterials can modify these cellular responses, enhancing their therapeutic potential. The aim of this research is to establish the influence of biomorphic silicon carbide ceramics (bioSiCs) surface topography on the proliferation and osteoblastic differentiation of mesenchymal stem cells and the potential synergistic effect of the ceramic porous structure together with vascular endothelial growth factor loading (VEGF) on the surface mediated osteoblastic differentiation. Three porous bioSiCs with important differences in their microstructure were obtained from different natural precursors. Samples loaded with or without VEGF through ionic interactions were cultured with human umbilical vein endothelial cells (HUVEC) or bone marrow derived mesenchymal stem cells (hMSCs). Cell behaviour and protein activity with regard to bioSiC porous structure and surface properties were analysed. An in vivo model (Chick Chorioallantoic Membrane; CAM) was used to assess the capability of the VEGF loaded systems to promote angiogenesis. Experimental data show that loaded systems were able to control the release of VEGF for up to 15 d ensuring the activity of the protein, increasing the proliferation of HUVECs and the formation of new blood vessels in the CAM. It was found that the selection of bioSiCs with a higher pore size promoted a higher concentration of osteoblastic differentiation markers of MSCs cultured on the surface of bioSiCs. Furthermore, the addition of VEGF to the systems was able to promote a faster osteoblastic differentiation according to the qPCR results, suggesting a synergy between both the surface properties and the controlled release of the growth factor. The VEGF loaded sapelli bioSiC was found to be the most promising material for bone tissue engineering applications.

Revisiting the role of hCG: new regulation of the angiogenic factor EG-VEGF and its receptors.

PubMed

Brouillet, S; Hoffmann, P; Chauvet, S; Salomon, A; Chamboredon, S; Sergent, F; Benharouga, M; Feige, J J; Alfaidy, N

2012-05-01

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an angiogenic factor reported to be specific for endocrine tissues, including the placenta. Its biological activity is mediated via two G protein-coupled receptors, prokineticin receptor 1 (PROKR1) and prokineticin receptor 2 (PROKR2). We have recently shown that (i) EG-VEGF expression peaks between the 8th and 11th weeks of gestation, (ii) its mRNA and protein levels are up-regulated by hypoxia, (iii) EG-VEGF is a negative regulator of trophoblast invasion and (iv) its circulating levels are increased in preeclampsia (PE), the most threatening pathology of pregnancy. Here, we investigated the regulation of the expression of EG-VEGF and its receptors by hCG, a key pregnancy hormone that is also deregulated in PE. During the first trimester of pregnancy, hCG and EG-VEGF exhibit the same pattern of expression, suggesting that EG-VEGF is potentially regulated by hCG. Both placental explants (PEX) and primary cultures of trophoblasts from the first trimester of pregnancy were used to investigate this hypothesis. Our results show that (i) LHCGR, the hCG receptor, is expressed both in cyto- and syncytiotrophoblasts, (ii) hCG increases EG-VEGF, PROKR1 and PROKR2 mRNA and protein expression in a dose- and time-dependent manner, (iii) hCG increases the release of EG-VEGF from PEX conditioned media, (iv) hCG effects are transcriptional and post-transcriptional and (v) the hCG effects are mediated by cAMP via cAMP response elements present in the EG-VEGF promoter region. Altogether, these results demonstrate a new role for hCG in the regulation of EG-VEGF and its receptors, an emerging regulatory system in placental development.

Novel approach for a PTX/VEGF dual drug delivery system in cardiovascular applications-an innovative bulk and surface drug immobilization.

PubMed

Wulf, Katharina; Teske, Michael; Matschegewski, Claudia; Arbeiter, Daniela; Bajer, Dalibor; Eickner, Thomas; Schmitz, Klaus-Peter; Grabow, Niels

2018-06-01

The successive incorporation of several drugs into the polymeric bulk of implants mostly results in loss of considerable quantity of one drug, and/or the loss in quality of the coating and also in changes of drug release time points. A dual drug delivery system (DDDS) based on poly-L-lactide (PLLA) copolymers combining the effective inhibition of smooth muscle cell proliferation while simultaneously promoting re-endothelialization was successfully developed. To overcome possible antagonistic drug interactions and the limitation of the polymeric bulk material as release system for dual drugs, a novel concept which combines the bulk and surface drug immobilization for a DDDS was investigated. The advantage of this DDDS is that the bulk incorporation of fluorescein diacetate (FDAc) (model drug for paclitaxel (PTX)) via spray coating enhanced the subsequent cleavable surface coupling of vascular endothelial growth factor (VEGF) via the crosslinker bissulfosuccinimidyl suberate (BS 3 ). In the presence of the embedded FDAc, the VEGF loading and release are about twice times higher than in absence. Furthermore, the DDDS combines the diffusion drug delivery (FDAc or PTX) and the chemical controlled drug release, VEGF via hydrolysable ester bonds, without loss in quantity and quality of the drug release curves. Additionally, the performed in vitro biocompatibility study showed the bimodal influences of PTX and VEGF on human endothelial EA.hy926 cells. In conclusion, it was possible to show the feasibility to develop a novel DDDS which has a high potential for the medical application due to the possible easy and short modification of a polymer-based PTX delivery system.

Streptococcus sanguinis-induced cytokine and matrix metalloproteinase-1 release from platelets

PubMed Central

2014-01-01

Background Streptococcus sanguinis (S.sanguinis), a predominant bacterium in the human oral cavity, has been widely associated with the development of infective endocarditis. Platelets play both a haemostatic function and can influence both innate and adaptive immune responses. Previous studies have shown that S.sanguinis can interact with, and activate, platelets. Results The aim of this study was to determine whether S.sanguinis stimulates the release of matrix metalloproteinases (MMPs) 1, 2 and 9 and the pro-inflammatory mediators SDF-1, VEGF and sCD40L, from platelets and to subsequently pharmacologically address the release mechanism (s). S.sanguinis stimulated the release of MMP-1, SDF-1, VEGF and sCD40L from platelets and inhibitors of cyclooxygenase and phosphatidylinositol 3-kinase, and antagonists of the αIIbβ3 integrin and glycoprotein Ib, each inhibited the secretion of all factors. Conclusions Therefore the release of MMP-1, SDF-1, VEGF and sCD40L occurs late in the platelet response to S.sanguinis and highlights the complex intracellular signalling pathways stimulated in response to S.sanguinis which lead to haemostasis, MMP and pro-inflammatory mediator secretion. PMID:24755160

In vitro characterizations of mesoporous hydroxyapatite as a controlled release delivery device for VEGF in orthopedic applications.

PubMed

Poh, Chye Khoon; Ng, Suxiu; Lim, Tee Yong; Tan, Hark Chuan; Loo, Joachim; Wang, Wilson

2012-11-01

Following bone implant surgery, prolonged ischemic conditions at the implant site often result in postsurgical complications like failure of osseointegration at the bone-implant interface which can lead to implant failure. Thus, restoration of the vascular supply is paramount to the proper development of the bone. High surface area mesostructured materials have been shown to be attractive candidates for bone regeneration to enhance cell adhesion and cell proliferation. This study uses hydroxyapatite, a naturally occurring mineral in the bone, fabricated to a range of suitable pore sizes, infused with vascular endothelial growth factor (VEGF), to be progressively released to stimulate revascularization. In this study, several characterizations including nitrogen adsorption analysis, Fourier-transformed infrared spectroscopy, X-ray diffraction, field emission scanning electron microscope, and transmission electron microscope were used to evaluate the synthesized mesoporous hydroxyapatite (MHA). The results showed that MHA can gradually release VEGF for enhancing revascularization, which is beneficial for orthopedic applications. Copyright © 2012 Wiley Periodicals, Inc.

Cyclic strain alters the expression and release of angiogenic factors by human tendon cells.

PubMed

Mousavizadeh, Rouhollah; Khosravi, Shahram; Behzad, Hayedeh; McCormack, Robert G; Duronio, Vincent; Scott, Alex

2014-01-01

Angiogenesis is associated with the tissue changes underlying chronic overuse tendinopathy. We hypothesized that repetitive, cyclic loading of human tendon cells would lead to increased expression and activity of angiogenic factors. We subjected isolated human tendon cells to overuse tensile loading using an in vitro model (1 Hz, 10% equibiaxial strain). We found that mechanically stimulated human tendon cells released factors that promoted in vitro proliferation and tube formation by human umbilical vein endothelial cells (HUVEC). In response to cyclic strain, there was a transient increase in the expression of several angiogenic genes including ANGPTL4, FGF-2, COX-2, SPHK1, TGF-alpha, VEGF-A and VEGF-C, with no change in anti-angiogenic genes (BAI1, SERPINF1, THBS1 and 2, TIMP1-3). Cyclic strain also resulted in the extracellular release of ANGPTL4 protein by tendon cells. Our study is the first report demonstrating the induction of ANGPTL4 mRNA and release of ANGPTL4 protein in response to cyclic strain. Tenocytes may contribute to the upregulation of angiogenesis during the development of overuse tendinopathy.

Cyclic Strain Alters the Expression and Release of Angiogenic Factors by Human Tendon Cells

PubMed Central

Mousavizadeh, Rouhollah; Khosravi, Shahram; Behzad, Hayedeh; McCormack, Robert G.; Duronio, Vincent; Scott, Alex

2014-01-01

Angiogenesis is associated with the tissue changes underlying chronic overuse tendinopathy. We hypothesized that repetitive, cyclic loading of human tendon cells would lead to increased expression and activity of angiogenic factors. We subjected isolated human tendon cells to overuse tensile loading using an in vitro model (1 Hz, 10% equibiaxial strain). We found that mechanically stimulated human tendon cells released factors that promoted in vitro proliferation and tube formation by human umbilical vein endothelial cells (HUVEC). In response to cyclic strain, there was a transient increase in the expression of several angiogenic genes including ANGPTL4, FGF-2, COX-2, SPHK1, TGF-alpha, VEGF-A and VEGF-C, with no change in anti-angiogenic genes (BAI1, SERPINF1, THBS1 and 2, TIMP1-3). Cyclic strain also resulted in the extracellular release of ANGPTL4 protein by tendon cells. Our study is the first report demonstrating the induction of ANGPTL4 mRNA and release of ANGPTL4 protein in response to cyclic strain. Tenocytes may contribute to the upregulation of angiogenesis during the development of overuse tendinopathy. PMID:24824595

Platelet Vascular Endothelial Growth Factor is a Potential Mediator of Transfusion-Related Acute Lung Injury.

PubMed

Maloney, James P; Ambruso, Daniel R; Voelkel, Norbert F; Silliman, Christopher C

The occurrence of non-hemolytic transfusion reactions is highest with platelet and plasma administration. Some of these reactions are characterized by endothelial leak, especially transfusion related acute lung injury (TRALI). Elevated concentrations of inflammatory mediators secreted by contaminating leukocytes during blood product storage may contribute to such reactions, but platelet-secreted mediators may also contribute. We hypothesized that platelet storage leads to accumulation of the endothelial permeability mediator vascular endothelial growth factor (VEGF), and that intravascular administration of exogenous VEGF leads to extensive binding to its lung receptors. Single donor, leukocyte-reduced apheresis platelet units were sampled over 5 days of storage. VEGF protein content of the centrifuged supernatant was determined by ELISA, and the potential contribution of VEGF from contaminating leukocytes was quantified. Isolated-perfused rat lungs were used to study the uptake of radiolabeled VEGF administered intravascularly, and the effect of unlabeled VEGF on lung leak. There was a time-dependent release of VEGF into the plasma fraction of the platelet concentrates (62 ± 9 pg/ml on day one, 149 ± 23 pg/ml on day 5; mean ± SEM, p<0.01, n=8) and a contribution by contaminating leukocytes was excluded. Exogenous 125I-VEGF bound avidly and specifically to the lung vasculature, and unlabeled VEGF in the lung perfusate caused vascular leak. Rising concentrations of VEGF occur during storage of single donor platelet concentrates due to platelet secretion or disintegration, but not due to leukocyte contamination. Exogenous VEGF at these concentrations rapidly binds to its receptors in the lung vessels. At higher VEGF concentrations, VEGF causes vascular leak in uninjured lungs. These data provide further evidence that VEGF may contribute to the increased lung permeability seen in TRALI associated with platelet products.

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion

PubMed Central

Gorin, Caroline; Rochefort, Gael Y.; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Germain, Stéphane

2016-01-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. Significance The results from the present study show that fibroblast growth factor-2 (FGF-2) priming is more efficient than hypoxia at increasing dental pulp stem cells derived from deciduous teeth (SHED)-induced vascularization compared with nonprimed controls. Together, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both hepatocyte growth factor and vascular endothelial growth factor. PMID:26798059

Hypoxia-mimicking bioactive glass regenerative effects on dental stem cells

NASA Astrophysics Data System (ADS)

Noor, Siti Noor Fazliah Mohd; Azevedo, Maria; Mohamad, Hasmaliza; Autefage, Hélène

2016-12-01

Vascularization is an important aspect of tissue regeneration. Hypoxia, low oxygen concentration, is a known stimulus for the release of vascular endothelial growth factors (VEGF) which play important roles in vascularization. The current study aimed to assess the effect of a cobalt-containing bioactive glass (BG) in stimulating hypoxia and promoting vascularization. To incorporate cobalt into BG, 1 mol% of calcium was substituting with cobalt, and this formulation was compared to the one without cobalt. Both BGs were processed via melt-derived method. The BG powders with particle size less than 38 µm were incubated with cell culture medium for 4 hours at 37°C on continuous rolling, and then the medium was filtered using 0.22 µm syringe filters. Prior to use, the BG-conditioned media were supplemented with 10% (v/v) fetal bovine serum and 1% (v/v) antibiotic-antimycotic, and were allowed to equilibrate overnight inside a CO2 incubator. The conditioned media were used on human dental stem cells (stem cells from permanent (DPSC) and deciduous (SHED) teeth) and assessed for their capacity to stimulate the release of angiogenic factors from the cells. The results showed that cobalt ions were released from the cobalt-containing BG, following partial dissolution of the glasses in cell culture medium, and promoted VEGF release from the cells. In conclusion, the incorporation of cobalt in BG may have potential to be used for tissue regeneration by promoting vascularization through the activation of hypoxia pathway and the release of VEGF.

MAPK/ERK signal pathway involved expression of COX-2 and VEGF by IL-1β induced in human endometriosis stromal cells in vitro

PubMed Central

Huang, Fengying; Cao, Jing; Liu, Qiuhong; Zou, Ying; Li, Hongyun; Yin, Tuanfang

2013-01-01

Objective: Now there are more and more evidences that Cyclooxygenase-2 (COX-2) plays an important role in angiogenesis of endometriosis (EMs). Vascular endothelial growth factor (VEGF) has a potent angiogenic activity. However, it is worth studying about the regulating mechanism of COX-2/COX-1 and VEGF in the development of human endometriosis in vitro. The current study was designed to investigate the effect of 4 cytokines on COX-2/COX-1 expression and the effect of IL-1β on VEGF release in human endometriosis stromal cells (ESC), and to explore the related signaling pathways involved in vitro. Methods: Isolation, culture and identification of ESC. Cells were treated with 4 cytokines, and the inhibitor mitogen-activated protein-Erk (MEK) and the inhibitor p38 mitogen-activated protein kinase (MAPK) prior to adding cytokine IL-1β. COX-2 protein expression was measured by western blot and VEGF secretion was determined by ELISA. Results: Among four kinds of cytokines, IL-1β treatment increased COX-2 protein expression and VEGF release in three ESC, and TNF-α had the same effect on COX-2 protein level as IL-1β only in ectopic and eutopic ESC, and MCSF had only slight effect on ectopic ESC. In contrast, cytokines had no effect on COX-1 expression. We also demonstrated that MAPK reduced the synthesis of COX-2 by IL-1β induced. COX-2 inhibitor reduced VEGF release by IL-1β induced. Conclusions: i) In human ESC in vitro, IL-1β up-regulated the COX-2 expression through the activation of p38 MAPK pathway, and not to COX-1. ii) Up-regulation of VEGF level by IL-1β treatment was found in human endometriosis stromal cell and COX-2 inhibitor was involved in this process. PMID:24133591

Poly(lactic-co-glycolide) polymer constructs cross-linked with human BMP-6 and VEGF protein significantly enhance rat mandible defect repair.

PubMed

Das, Anusuya; Fishero, Brian A; Christophel, J Jared; Li, Ching-Ju; Kohli, Nikita; Lin, Yong; Dighe, Abhijit S; Cui, Quanjun

2016-04-01

We have previously shown that the combined delivery of mesenchymal stem cells (MSCs), vascular endothelial growth factor (VEGF) and bone morphogenetic protein 6 (BMP-6) induces significantly more bone formation than that induced by the delivery of any single factor or a combination of any two factors. We now determine whether the exogenous addition of VEGF and BMP-6 is sufficient for bone healing when MSCs are not provided. Poly(lactic-co-glycolic acid) (PLAGA) microsphere-based three-dimensional scaffolds (P) were fabricated by thermal sintering of PLAGA microspheres. The scaffolds were chemically cross-linked with 200 ng recombinant human VEGF (P(VEGF)) or BMP-6 (P(BMP-6)) or both (P(VEGF+BMP-6)) by the EDC-NHS-MES method. Release of the proteins from the scaffolds was detected for 21 days in vitro which confirmed their comparable potential to supply the proteins in vivo. The scaffolds were delivered to a critical-sized mandibular defect created in 32 Sprague Dawley rats. Significant bone regeneration was observed only in rats with P(VEGF+BMP-6) scaffolds at weeks 2, 8 and 12 as revealed by micro-computer tomography. Vascular ingrowth was higher in the P(VEGF+BMP-6) group as seen by microfil imaging than in other groups. Trichrome staining revealed that a soft callus formed in P(VEGF), P(BMP-6) and P(VEGF+BMP-6) but not in P. MSCs isolated from rat femurs displayed expression of the bone-specific marker osteocalcin when cultured with P(VEGF), P(BMP-6), or P(VEGF+BMP-6) but not with P. Robust mineralization and increased alkaline phosphatase gene expression were seen in rat MSCs when cultured on P(VEGF+BMP-6) but not on P, P(VEGF), or P(BMP-6). Thus, unlike the delivery of VEGF or BMP-6 alone, the combined delivery of VEGF and BMP-6 to the bone defect significantly enhanced bone repair through the enhancement of angiogenesis and the differentiation of endogenously recruited MSCs into the bone repair site.

Identification of candidate angiogenic inhibitors processed by matrix metalloproteinase 2 (MMP-2) in cell-based proteomic screens: disruption of vascular endothelial growth factor (VEGF)/heparin affin regulatory peptide (pleiotrophin) and VEGF/Connective tissue growth factor angiogenic inhibitory complexes by MMP-2 proteolysis.

PubMed

Dean, Richard A; Butler, Georgina S; Hamma-Kourbali, Yamina; Delbé, Jean; Brigstock, David R; Courty, José; Overall, Christopher M

2007-12-01

Matrix metalloproteinases (MMPs) exert both pro- and antiangiogenic functions by the release of cytokines or proteolytically generated angiogenic inhibitors from extracellular matrix and basement membrane remodeling. In the Mmp2-/- mouse neovascularization is greatly reduced, but the mechanistic aspects of this remain unclear. Using isotope-coded affinity tag labeling of proteins analyzed by multidimensional liquid chromatography and tandem mass spectrometry we explored proteome differences between Mmp2-/- cells and those rescued by MMP-2 transfection. Proteome signatures that are hallmarks of proteolysis revealed cleavage of many known MMP-2 substrates in the cellular context. Proteomic evidence of MMP-2 processing of novel substrates was found. Insulin-like growth factor binding protein 6, follistatin-like 1, and cystatin C protein cleavage by MMP-2 was biochemically confirmed, and the cleavage sites in heparin affin regulatory peptide (HARP; pleiotrophin) and connective tissue growth factor (CTGF) were sequenced by matrix-assisted laser desorption ionization-time of flight mass spectrometry. MMP-2 processing of HARP and CTGF released vascular endothelial growth factor (VEGF) from angiogenic inhibitory complexes. The cleaved HARP N-terminal domain increased HARP-induced cell proliferation, whereas the HARP C-terminal domain was antagonistic and decreased cell proliferation and migration. Hence the unmasking of cytokines, such as VEGF, by metalloproteinase processing of their binding proteins is a new mechanism in the control of cytokine activation and angiogenesis.

Identification of Candidate Angiogenic Inhibitors Processed by Matrix Metalloproteinase 2 (MMP-2) in Cell-Based Proteomic Screens: Disruption of Vascular Endothelial Growth Factor (VEGF)/Heparin Affin Regulatory Peptide (Pleiotrophin) and VEGF/Connective Tissue Growth Factor Angiogenic Inhibitory Complexes by MMP-2 Proteolysis▿ †

PubMed Central

Dean, Richard A.; Butler, Georgina S.; Hamma-Kourbali, Yamina; Delbé, Jean; Brigstock, David R.; Courty, José; Overall, Christopher M.

2007-01-01

Matrix metalloproteinases (MMPs) exert both pro- and antiangiogenic functions by the release of cytokines or proteolytically generated angiogenic inhibitors from extracellular matrix and basement membrane remodeling. In the Mmp2−/− mouse neovascularization is greatly reduced, but the mechanistic aspects of this remain unclear. Using isotope-coded affinity tag labeling of proteins analyzed by multidimensional liquid chromatography and tandem mass spectrometry we explored proteome differences between Mmp2−/− cells and those rescued by MMP-2 transfection. Proteome signatures that are hallmarks of proteolysis revealed cleavage of many known MMP-2 substrates in the cellular context. Proteomic evidence of MMP-2 processing of novel substrates was found. Insulin-like growth factor binding protein 6, follistatin-like 1, and cystatin C protein cleavage by MMP-2 was biochemically confirmed, and the cleavage sites in heparin affin regulatory peptide (HARP; pleiotrophin) and connective tissue growth factor (CTGF) were sequenced by matrix-assisted laser desorption ionization-time of flight mass spectrometry. MMP-2 processing of HARP and CTGF released vascular endothelial growth factor (VEGF) from angiogenic inhibitory complexes. The cleaved HARP N-terminal domain increased HARP-induced cell proliferation, whereas the HARP C-terminal domain was antagonistic and decreased cell proliferation and migration. Hence the unmasking of cytokines, such as VEGF, by metalloproteinase processing of their binding proteins is a new mechanism in the control of cytokine activation and angiogenesis. PMID:17908800

In Vivo Efficacy of an Injectable Microsphere-Hydrogel Ocular Drug Delivery System.

PubMed

Osswald, Christian R; Guthrie, Micah J; Avila, Abigail; Valio, Joseph A; Mieler, William F; Kang-Mieler, Jennifer J

2017-09-01

Demonstrate in vivo that controlled and extended release of a low dose of anti-vascular endothelial growth factor (anti-VEGF) from a microsphere-hydrogel drug delivery system (DDS) has a therapeutic effect in a laser-induced rat model of choroidal neovascularization (CNV). Anti-VEGF (ranibizumab or aflibercept) was loaded into poly(lactic-co-glycolic acid) microspheres that were then suspended within an injectable poly(N-isopropylacrylamide)-based thermo-responsive hydrogel DDS.The DDS was shown previously to release bioactive anti-VEGF for ~200 days. CNV was induced using an Ar-green laser. The four experimental groups were as follows: (i) non-treated, (ii) drug-free DDS, (iii) anti-VEGF-loaded DDS, and (iv) bolus injection of anti-VEGF. CNV lesion areas were measured based on fluorescein angiograms and quantified using a multi-Otsu thresholding technique. Intraocular pressure (IOP) and dark-adapted electroretinogram (ERG) were also obtained pre- and post-treatment (1, 2, 4, 8, and 12 weeks). The anti-VEGF-loaded DDS group had significantly smaller (60%) CNV lesion areas than non-treated animals throughout the study. A small transient increase in IOP was seen immediately after injection; however, all IOP measurements at all time points were within the normal range. There were no significant changes in ERG maximal response compared to pre-treatment measurements for the drug-loaded DDS, which suggests no adverse effects on retinal cellular function. The current study demonstrates that the DDS can effectively decrease laser-induced CNV lesions in a murine model. Controlled and extended release from our DDS achieved greater treatment efficacy using an order of magnitude less drug than what is required with bolus administration. This suggests that our DDS may provide a significant advantage in the treatment of posterior segment eye diseases.

Diabetic Macular Edema: From Old Concepts to New Therapeutic Avenues

PubMed Central

Mansour, Ahmad M; Pulido, Jose S; Arevalo, J Fernando

2015-01-01

Diabetic macular edema (DME) is a significant cause of blindness in the working population and is currently challenging to treat. Current interventions include focal laser or intravitreal injections. This article outlines a new treatment protocol based on the theory that peripheral ischemia is the precursor to angiogenesis, which will ultimately gather its momentum at the fovea. Extreme peripheral light laser panretinal photocoagulation (PRP) back to the equator reduces excessive production of the vascular endothelial growth factor (VEGF) in the eye. This decreases VEGF-induced DME and provides long-term protection against the development of neovascularization. Initial exacerbation of DME often accompanies PRP. Therefore, injections of anti-VEGF agents (with or without dexamethasone implants) initially can forestall worsening of DME and prevent loss of vision. However, on the other hand, applying peripheral PRP and intraocular injections can induce posterior vitreous detachment (PVD). This could help release vitreomacular adhesions (VMA) and vitreomacular traction (VMT), thereby decreasing DME severity and improving the response to intravitreal injections. In the current approach, peripheral retinal photocoagulation should stop the drive for VEGF release; moreover, laser ablation should produce secondary, accidental, and beneficial PVD. This approach precludes focal laser therapy and paves the path for prolonged intervals between anti-VEGF therapy. PMID:27800500

Angiogenesis in calcium phosphate scaffolds by inorganic copper ion release.

PubMed

Barralet, Jake; Gbureck, Uwe; Habibovic, Pamela; Vorndran, Elke; Gerard, Catherine; Doillon, Charles J

2009-07-01

Angiogenesis in a tissue-engineered device may be induced by incorporating growth factors (e.g., vascular endothelial growth factor [VEGF]), genetically modified cells, and=or vascular cells. It represents an important process during the formation and repair of tissue and is essential for nourishment and supply of reparative and immunological cells. Inorganic angiogenic factors, such as copper ions, are therefore of interest in the fields of regenerative medicine and tissue engineering due to their low cost, higher stability, and potentially greater safety compared with recombinant proteins or genetic engineering approaches. The purpose of this study was to compare tissue responses to 3D printed macroporous bioceramic scaffolds implanted in mice that had been loaded with either VEGF or copper sulfate. These factors were spatially localized at the end of a single macropore some 7 mm from the surface of the scaffold. Controls without angiogenic factors exhibited only poor tissue growth within the blocks; in contrast, low doses of copper sulfate led to the formation of microvessels oriented along the macropore axis. Further, wound tissue ingrowth was particularly sensitive to the quantity of copper sulfate and was enhanced at specific concentrations or in combination with VEGF. The potential to accelerate and guide angiogenesis and wound healing by copper ion release without the expense of inductive protein(s) is highly attractive in the area of tissue-engineered bone and offers significant future potential in the field of regenerative biomaterials.

Sequential delivery of TAT-HSP27 and VEGF using microsphere/hydrogel hybrid systems for therapeutic angiogenesis.

PubMed

Shin, Seung-Hwa; Lee, Jangwook; Lim, Kwang Suk; Rhim, Taiyoun; Lee, Sang Kyung; Kim, Yong-Hee; Lee, Kuen Yong

2013-02-28

Ischemic disease is associated with high mortality and morbidity rates, and therapeutic angiogenesis via systemic or local delivery of protein drugs is one potential approach to treat the disease. In this study, we hypothesized that combined delivery of TAT-HSP27 (HSP27 fused with transcriptional activator) and VEGF could enhance the therapeutic efficacy in an ischemic mouse model, and that sequential release could be critical in therapeutic angiogenesis. Alginate hydrogels containing TAT-HSP27 as an anti-apoptotic agent were prepared, and porous PLGA microspheres loaded with VEGF as an angiogenic agent were incorporated into the hydrogels to prepare microsphere/hydrogel hybrid delivery systems. Sequential in vitro release of TAT-HSP27 and VEGF was achieved by the hybrid systems. TAT-HSP27 was depleted from alginate gels in 7 days, while VEGF was continually released for 28 days. The release rate of VEGF was attenuated by varying the porous structures of PLGA microspheres. Sequential delivery of TAT-HSP27 and VEGF was critical to protect against muscle degeneration and fibrosis, as well as to promote new blood vessel formation in the ischemic site of a mouse model. This approach to controlling the sequential release behaviors of multiple drugs could be useful in the design of novel drug delivery systems for therapeutic angiogenesis. Copyright © 2012 Elsevier B.V. All rights reserved.

Constitutive Endocytosis of VEGFR2 Protects the Receptor against Shedding.

PubMed

Basagiannis, Dimitris; Christoforidis, Savvas

2016-08-05

VEGFR2 plays a fundamental role in blood vessel formation and in life threatening diseases, such as cancer angiogenesis and cardiovascular disorders. Although inactive growth factor receptors are mainly localized at the plasma membrane, VEGFR2 undergoes constitutive endocytosis (in the absence of ligand) and recycling. Intriguingly, the significance of these futile transport cycles of VEGFR2 remains unclear. Here we found that, unexpectedly, the function of constitutive endocytosis of VEGFR2 is to protect the receptor against plasma membrane cleavage (shedding), thereby preserving the functional state of the receptor until the time of activation by VEGF. Inhibition of constitutive endocytosis of VEGFR2, by interference with the function of clathrin, dynamin, or Rab5, increases dramatically the cleavage/shedding of VEGFR2. Shedding of VEGFR2 produces an N-terminal soluble fragment (100 kDa, s100), which is released in the extracellular space, and a residual C-terminal part (130 kDa, p130) that remains integrated at the plasma membrane. The released soluble fragment (s100) co-immunoprecipitates with VEGF, in line with the topology of the VEGF-binding domain at the N terminus of VEGFR2. Increased shedding of VEGFR2 (via inhibition of constitutive endocytosis) results in reduced response to VEGF, consistently with the loss of the VEGF-binding domain from the membrane remnant of VEGFR2. These data suggest that constitutive internalization of VEGFR2 protects the receptor against shedding and provides evidence for an unprecedented mechanism via which endocytosis can regulate the fate and activity of growth factor receptors. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Constitutive Endocytosis of VEGFR2 Protects the Receptor against Shedding*

PubMed Central

Basagiannis, Dimitris; Christoforidis, Savvas

2016-01-01

VEGFR2 plays a fundamental role in blood vessel formation and in life threatening diseases, such as cancer angiogenesis and cardiovascular disorders. Although inactive growth factor receptors are mainly localized at the plasma membrane, VEGFR2 undergoes constitutive endocytosis (in the absence of ligand) and recycling. Intriguingly, the significance of these futile transport cycles of VEGFR2 remains unclear. Here we found that, unexpectedly, the function of constitutive endocytosis of VEGFR2 is to protect the receptor against plasma membrane cleavage (shedding), thereby preserving the functional state of the receptor until the time of activation by VEGF. Inhibition of constitutive endocytosis of VEGFR2, by interference with the function of clathrin, dynamin, or Rab5, increases dramatically the cleavage/shedding of VEGFR2. Shedding of VEGFR2 produces an N-terminal soluble fragment (100 kDa, s100), which is released in the extracellular space, and a residual C-terminal part (130 kDa, p130) that remains integrated at the plasma membrane. The released soluble fragment (s100) co-immunoprecipitates with VEGF, in line with the topology of the VEGF-binding domain at the N terminus of VEGFR2. Increased shedding of VEGFR2 (via inhibition of constitutive endocytosis) results in reduced response to VEGF, consistently with the loss of the VEGF-binding domain from the membrane remnant of VEGFR2. These data suggest that constitutive internalization of VEGFR2 protects the receptor against shedding and provides evidence for an unprecedented mechanism via which endocytosis can regulate the fate and activity of growth factor receptors. PMID:27298320

Synergistic Effects of GDNF and VEGF on Lifespan and Disease Progression in a Familial ALS Rat Model

PubMed Central

Krakora, Dan; Mulcrone, Patrick; Meyer, Michael; Lewis, Christina; Bernau, Ksenija; Gowing, Genevieve; Zimprich, Chad; Aebischer, Patrick; Svendsen, Clive N; Suzuki, Masatoshi

2013-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons in the brain and spinal cord. We have recently shown that human mesenchymal stem cells (hMSCs) modified to release glial cell line-derived neurotrophic factor (GDNF) decrease disease progression in a rat model of ALS when delivered to skeletal muscle. In the current study, we determined whether or not this effect could be enhanced by delivering GDNF in concert with other trophic factors. hMSC engineered to secrete GDNF (hMSC-GDNF), vascular endothelial growth factor (hMSC-VEGF), insulin-like growth factor-I (hMSC-IGF-I), or brain-derived neurotrophic factor (hMSC-BDNF), were prepared and transplanted bilaterally into three muscle groups. hMSC-GDNF and hMSC-VEGF prolonged survival and slowed the loss of motor function, but hMSC-IGF-I and hMSC-BDNF did not have any effect. We then tested the efficacy of a combined ex vivo delivery of GDNF and VEGF in extending survival and protecting neuromuscular junctions (NMJs) and motor neurons. Interestingly, the combined delivery of these neurotrophic factors showed a strong synergistic effect. These studies further support ex vivo gene therapy approaches for ALS that target skeletal muscle. PMID:23712039

Scaffold Composition Determines the Angiogenic Outcome of Cell-Based Vascular Endothelial Growth Factor Expression by Modulating Its Microenvironmental Distribution.

PubMed

Gaudiello, Emanuele; Melly, Ludovic; Cerino, Giulia; Boccardo, Stefano; Jalili-Firoozinezhad, Sasan; Xu, Lifen; Eckstein, Friedrich; Martin, Ivan; Kaufmann, Beat A; Banfi, Andrea; Marsano, Anna

2017-12-01

Delivery of genetically modified cells overexpressing Vascular Endothelial Growth Factor (VEGF) is a promising approach to induce therapeutic angiogenesis in ischemic tissues. The effect of the protein is strictly modulated by its interaction with the components of the extracellular matrix. Its therapeutic potential depends on a sustained but controlled release at the microenvironmental level in order to avoid the formation of abnormal blood vessels. In this study, it is hypothesized that the composition of the scaffold plays a key role in modulating the binding, hence the therapeutic effect, of the VEGF released by 3D-cell constructs. It is found that collagen sponges, which poorly bind VEGF, prevent the formation of localized hot spots of excessive concentration, therefore, precluding the development of aberrant angiogenesis despite uncontrolled expression by a genetically engineered population of adipose tissue-derived stromal cells. On the contrary, after seeding on VEGF-binding egg-white scaffolds, the same cell population caused aberrantly enlarged vascular structures after 14 d. Collagen-based engineered tissues also induced a safe and efficient angiogenesis in both the patch itself and the underlying myocardium in rat models. These findings open new perspectives on the control and the delivery of proangiogenic stimuli, and are fundamental for the vascularization of engineered tissues/organs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Local induction of lymphangiogenesis with engineered fibrin-binding VEGF-C promotes wound healing by increasing immune cell trafficking and matrix remodeling.

PubMed

Güç, Esra; Briquez, Priscilla S; Foretay, Didier; Fankhauser, Manuel A; Hubbell, Jeffrey A; Kilarski, Witold W; Swartz, Melody A

2017-07-01

Lymphangiogenesis occurs in inflammation and wound healing, yet its functional roles in these processes are not fully understood. Consequently, clinically relevant strategies for therapeutic lymphangiogenesis remain underdeveloped, particularly using growth factors. To achieve controlled, local capillary lymphangiogenesis with protein engineering and determine its effects on fluid clearance, leukocyte trafficking, and wound healing, we developed a fibrin-binding variant of vascular endothelial growth factor C (FB-VEGF-C) that is slowly released upon demand from infiltrating cells. Using a novel wound healing model, we show that implanted fibrin containing FB-VEGF-C, but not free VEGF-C, could stimulate local lymphangiogenesis in a dose-dependent manner. Importantly, the effects of FB-VEGF-C were restricted to lymphatic capillaries, with no apparent changes to blood vessels and downstream collecting vessels. Leukocyte intravasation and trafficking to lymph nodes were increased in hyperplastic lymphatics, while fluid clearance was maintained at physiological levels. In diabetic wounds, FB-VEGF-C-induced lymphangiogenesis increased extracellular matrix deposition and granulation tissue thickening, indicators of improved wound healing. Together, these results indicate that FB-VEGF-C is a promising strategy for inducing lymphangiogenesis locally, and that such lymphangiogenesis can promote wound healing by enhancing leukocyte trafficking without affecting downstream lymphatic collecting vessels. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

VEGF secretion during hypoxia depends on free radicals-induced Fyn kinase activity in mast cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garcia-Roman, Jonathan; Ibarra-Sanchez, Alfredo; Lamas, Monica

2010-10-15

Research highlights: {yields} Bone marrow-derived mast cells (BMMCs) secrete functional VEGF but do not degranulate after Cobalt chloride-induced hypoxia. {yields} CoCl{sub 2}-induced VEGF secretion in mast cells occurs by a Ca{sup 2+}-insensitive but brefeldin A and Tetanus toxin-sensitive mechanism. {yields} Trolox and N-acetylcysteine inhibit hypoxia-induced VEGF secretion but only Trolox inhibits Fc{epsilon}RI-dependent anaphylactic degranulation in mast cells. {yields} Src family kinase Fyn activation after free radical production is necessary for hypoxia-induced VEGF secretion in mast cells. -- Abstract: Mast cells (MC) have an important role in pathologic conditions such as asthma and chronic obstructive pulmonary disease (COPD), where hypoxia conducemore » to deleterious inflammatory response. MC contribute to hypoxia-induced angiogenesis producing factors such as vascular endothelial growth factor (VEGF), but the mechanisms behind the control of hypoxia-induced VEGF secretion in this cell type is poorly understood. We used the hypoxia-mimicking agent cobalt chloride (CoCl{sub 2}) to analyze VEGF secretion in murine bone marrow-derived mast cells (BMMCs). We found that CoCl{sub 2} promotes a sustained production of functional VEGF, able to induce proliferation of endothelial cells in vitro. CoCl{sub 2}-induced VEGF secretion was independent of calcium rise but dependent on tetanus toxin-sensitive vesicle-associated membrane proteins (VAMPs). VEGF exocytosis required free radicals formation and the activation of Src family kinases. Interestingly, an important deficiency on CoCl{sub 2}-induced VEGF secretion was observed in Fyn kinase-deficient BMMCs. Moreover, Fyn kinase was activated by CoCl{sub 2} in WT cells and this activation was prevented by treatment with antioxidants such as Trolox and N-acetylcysteine. Our results show that BMMCs are able to release VEGF under hypoxic conditions through a tetanus toxin-sensitive mechanism, promoted by free radicals-dependent Fyn kinase activation.« less

VEGF released from a fibrin biomatrix increases VEGFR-2 expression and improves early outcome after ischaemia-reperfusion injury.

PubMed

Moritz, Martina; Pfeifer, Sabine; Balmayor, Elizabeth R; Mittermayr, Rainer; Wolbank, Susanne; Redl, Heinz; van Griensven, Martijn

2017-07-01

Skeletal ischaemia-reperfusion (I-R) injury may influence patient outcome after severe vascular trauma or clamping of major vessels. The aim of this study was to observe whether locally applied vascular endothelial growth factor (VEGF) in fibrin could induce the expression of VEGF-receptor-2 (VEGFR-2) and improve the outcome after I-R injury. Transgenic mice expressing VEGFR-2 promoter-controlled luciferase were used for the assessment of VEGFR-2 expression. Ischaemia was induced for 2 h by a tension-controlled tourniquet to the hind limb, followed by 24 h of reperfusion. The animals were locally injected subcutaneously with fibrin sealant containing 20 or 200 ng VEGF; control animals received no treatment or fibrin sealant application. In vivo VEGFR-2 expression was quantified upon administration of luciferin at several observation times. For oedema and inflammation quantification, wet:dry ratio measurements and a myeloperoxidase assay of the muscle tissue were performed. Laser Doppler imaging showed that ischaemia was present and that the blood flow had returned to baseline levels after 24 h of reperfusion. VEGFR-2 expression levels in the fibrin + 200 ng VEGF were significantly higher than in all other groups. Granulocyte infiltration was reduced in both treatment groups, as well as reduced oedema formation. These results showed that VEGF released from fibrin had a positive effect on early I-R outcome in a mouse model, possibly via VEGFR-2. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Thicker carotid intima-media thickness and increased plasma VEGF levels suffered by post-acute thrombotic stroke patients.

PubMed

Yueniwati, Yuyun; Darmiastini, Ni Komang; Arisetijono, Eko

2016-01-01

Atherosclerosis causes reduction of the oxygen supply to structures in the far arterial wall, provoking the release of factors that drive angiogenesis of vasa vasorum, including VEGF. Other studies have revealed the inflammatory response in atherosclerosis and the role of platelet factor 4 (PF4) as an anti-angiogenic chemokine through the inhibition of VEGF. This cross-sectional study aims at measuring the effect of atherosclerosis assessed through carotid intima-media thickness (CIMT) against plasma VEGF levels in patients with post-acute thrombotic stroke. CIMT was assessed sonographically using GE Logiq S6 with 13 MHz frequency linear probe. VEGF-A plasma levels were measured using enzyme-linked immunosorbent assay (ELISA) method. Differences among variables were compared statistically. The data were analyzed using Pearson correlation. A total of 25 patients with post-acute thrombotic stroke were identified in days 7 to 90. CIMT thickening was indicated in 88% of patients (1.202 ± 0.312 mm), while an increase in plasma VEGF was identified in all patients (178.28 ± 93.96 ng/mL). There was no significant correlation between CIMT and plasma VEGF levels in patients with post-acute thrombotic stroke ( p =0.741). A significant correlation was recognized between CIMT and total cholesterol ( p =0.029) and low-density lipoprotein ( p =0.018). There were no significant correlations between CIMT and plasma VEGF levels in patients with post-acute thrombotic stroke. However, plasma VEGF increased in patients with thrombotic stroke. CIMT measurement is a promising noninvasive modality to assess the vascular condition of patients with stroke and diabetes, while plasma VEGF cannot specifically assess vascular condition as it can be triggered by ischemic conditions in tissues of the whole body.

Bevacizumab plus fotemustine as first-line treatment in metastatic melanoma patients: clinical activity and modulation of angiogenesis and lymphangiogenesis factors.

PubMed

Del Vecchio, Michele; Mortarini, Roberta; Canova, Stefania; Di Guardo, Lorenza; Pimpinelli, Nicola; Sertoli, Mario R; Bedognetti, Davide; Queirolo, Paola; Morosini, Paola; Perrone, Tania; Bajetta, Emilio; Anichini, Andrea

2010-12-01

To assess the clinical and biological activity of the association of bevacizumab and fotemustine as first-line treatment in advanced melanoma patients. Previously untreated, metastatic melanoma patients (n = 20) received bevacizumab (at 15 mg/kg every 3 weeks) and fotemustine (100 mg/m² by intravenous administration on days 1, 8, and 15, repeated after 4 weeks) in a multicenter, single-arm, open-label, phase II study. Primary endpoint was the best overall response rate; other endpoints were toxicity, time to progression (TTP), and overall survival (OS). Serum cytokines, angiogenesis, and lymphangiogenesis factors were monitored by multiplex arrays and by in vitro angiogenesis assays. Effects of fotemustine on melanoma cells, in vitro, on vascular endothelial growth factor (VEGF)-C release and apoptosis were assessed by ELISA and flow cytometry, respectively. One complete response, 2 partial responses (PR), and 10 patients with stable disease were observed. TTP and OS were 8.3 and 20.5 months, respectively. Fourteen patients experienced adverse events of toxicity grade 3-4. Serum VEGF-A levels in evaluated patients (n = 15) and overall serum proangiogenic activity were significantly inhibited. A significant reduction in VEGF-C levels was found in several post-versus pretherapy serum samples. In vitro, fotemustine inhibited VEGF-C release by melanoma cells without inducing significant cell death. Serum levels of interleukin (IL)-10 and IL-12p70 showed the highest levels in sera of PR patients, compared with patients with stable or progressive disease whereas IL-23 showed the opposite pattern. The combination of bevacizumab plus fotemustine has clinical activity in advanced melanoma and promotes systemic modulation of angiogenesis and lymphangiogenesis factors. ©2010 AACR.

Effect of thalidomide and arsenic trioxide on the release of tumor necrosis factor-α and vascular endothelial growth factor from the KG-1a human acute myelogenous leukemia cell line.

PubMed

Girgis, Erian H; Mahoney, John P; Khalil, Rafaat H; Soliman, Magdi R

2010-07-01

Studies conducted in our lab have indicated that thalidomide cytotoxicity in the KG-1a human acute myelogenous leukemia (AML) cell line was enhanced by combining it with arsenic trioxide. The current investigation was conducted in order to evaluate the effect of thalidomide either alone or in combination with arsenic trioxide on the release of tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) from this cell line in an attempt to clarify its possible cytotoxic mechanism(s). Human AML cell line KG-1a was used in this study. The cells were cultured for 48 h in the presence or absence of thalidomide (5 mg/l), and or arsenic trioxide (4 μM). The levels of TNF-α and VEGF in the supernatant were determined by ELISA. Results obtained indicate that the levels of TNF-α in the supernatant of KG-1a cell cultures incubated with thalidomide, arsenic trioxide, or combination were statistically lower than those observed in the supernatant of control cells (2.89, 5.07, 4.15 and 16.88 pg/ml, respectively). However, the levels of VEGF in the supernatant of thalidomide-treated cells were statistically higher than those in the supernatant of control cells (69.61 vs. 11.48 pg/l). Arsenic trioxide, whether alone or in combination with thalidomide, did not produce any statistically significant difference in the levels of VEGF as compared to the control or thalidomide-treated cell supernatant. These findings indicate that thalidomide and the arsenic trioxide inhibition of TNF-α production by KG-1a cells may play an important role in their cytotoxic effect.

Enzymatically cross-linked injectable alginate-g-pyrrole hydrogels for neovascularization.

PubMed

Devolder, Ross; Antoniadou, Eleni; Kong, Hyunjoon

2013-11-28

Microparticles capable of releasing protein drugs are often incorporated into injectable hydrogels to minimize their displacement at an implantation site, reduce initial drug burst, and further control drug release rates over a broader range. However, there is still a need to develop methods for releasing drug molecules over extended periods of time, in order to sustain the bioactivity of drug molecules at an implantation site. In this study, we hypothesized that a hydrogel formed through the cross-linking of pyrrole units linked to a hydrophilic polymer would release protein drugs in a more sustained manner, because of an enhanced association between cross-linked pyrrole groups and the drug molecules. To examine this hypothesis, we prepared hydrogels of alginate substituted with pyrrole groups, alginate-g-pyrrole, through a horse-radish peroxidase (HRP)-activated cross-linking of the pyrrole groups. The hydrogels were encapsulated with poly(lactic-co-glycolic acid) (PLGA) microparticles loaded with vascular endothelial growth factor (VEGF). The resulting hydrogel system released VEGF in a more sustained manner than Ca(2+) alginate or Ca(2+) alginate-g-pyrrole gel systems. Finally, implantations of the VEGF-releasing HRP-activated alginate-g-pyrrole hydrogel system on chicken chorioallantoic membranes resulted in the formation of blood vessels in higher densities and with larger diameters, compared to other control conditions. Overall, the drug releasing system developed in this study will be broadly useful for regulating release rates of a wide array of protein drugs, and further enhance the quality of protein drug-based therapies. © 2013 Elsevier B.V. All rights reserved.

Extracellular regulation of VEGF: isoforms, proteolysis, and vascular patterning

PubMed Central

Vempati, Prakash; Popel, Aleksander S.; Mac Gabhann, Feilim

2014-01-01

The regulation of vascular endothelial growth factor A (VEGF) is critical to neovascularization in numerous tissues under physiological and pathological conditions. VEGF has multiple isoforms, created by alternative splicing or proteolytic cleavage, and characterized by different receptor-binding and matrix-binding properties. These isoforms are known to give rise to a spectrum of angiogenesis patterns marked by differences in branching, which has functional implications for tissues. In this review, we detail the extensive extracellular regulation of VEGF and the ability of VEGF to dictate the vascular phenotype. We explore the role of VEGF-releasing proteases and soluble carrier molecules on VEGF activity. While proteases such as MMP9 can ‘release’ matrix-bound VEGF and promote angiogenesis, for example as a key step in carcinogenesis, proteases can also suppress VEGF’s angiogenic effects. We explore what dictates pro- or anti-angiogenic behavior. We also seek to understand the phenomenon of VEGF gradient formation. Strong VEGF gradients are thought to be due to decreased rates of diffusion from reversible matrix binding, however theoretical studies show that this scenario cannot give rise to lasting VEGF gradients in vivo. We propose that gradients are formed through degradation of sequestered VEGF. Finally, we review how different aspects of the VEGF signal, such as its concentration, gradient, matrix-binding, and NRP1-binding can differentially affect angiogenesis. We explore how this allows VEGF to regulate the formation of vascular networks across a spectrum of high to low branching densities, and from normal to pathological angiogenesis. A better understanding of the control of angiogenesis is necessary to improve upon limitations of current angiogenic therapies. PMID:24332926

ACTIVATION OF PLATELET-RICH PLASMA USING SOLUBLE TYPE I COLLAGEN

PubMed Central

Fufa, Duretti; Shealy, Blake; Jacobson, May; Kevy, Sherwin; Murray, Martha M.

2008-01-01

PURPOSE Platelet-rich plasma (PRP) has recently been found to be a useful delivery system for growth factors important in oral tissue healing. However, application of PRP in a liquid form to a wound site within the oral cavity can be complicated by significant loss of the PRP into the surrounding oral space unless gelation via the clotting mechanism is accomplished. Gelation is currently accomplished using bovine thrombin; however, rare but serious complications of this method have led to the search for alternative clotting mechanisms, including the use of soluble collagen as a clotting activator. In this paper, our hypothesis was that soluble Type I collagen would be as effective as bovine thrombin in causing clotting of the PRP and of stimulating growth factor release from the platelets and granulocytes. MATERIALS AND METHODS PRP from human donors was clotted using Type I collagen or bovine thrombin. Clot retraction was determined by measuring clot diameters over time. The release of PDGF-AB, TGF-β1 and VEGF from both types of clots was measured over 10 days using ELISA. RESULTS Clots formed using Type I collagen had far less retraction than those formed with bovine thrombin. Bovine thrombin and Type I collagen stimulated similar release of PDGF-AB and VEGF between 1 and 10 days; however, thrombin activation resulted in a greater release of TGF-β1 during the first five days after activation. CONCLUSIONS The use of Type I collagen to activate clotting of PRP may be a safe and effective alternative to bovine thrombin. The use of collagen results in less clot retraction and equal release of PDGF-AB and VEGF when compared to currently available methods of clot activation. PMID:18355591

Oxidized LDL binding to LOX-1 upregulates VEGF expression in cultured bovine chondrocytes through activation of PPAR-{gamma}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kanata, Sohya; Akagi, Masao; Nishimura, Shunji

It has been reported that vascular endothelial growth factor (VEGF) and its receptors play an important role in the destruction of articular cartilage in osteoarthritis through increased production of matrix metalloproteinases. We investigated whether the oxidized low-density lipoprotein (ox-LDL) binding to lectin-like ox-LDL receptor-1 (LOX-1) upregulates VEGF expression in cultured bovine articular chondrocytes (BACs). Ox-LDL markedly increased VEGF mRNA expression and protein release in time- and dose-dependent manners, which was significantly suppressed by anti-LOX-1 antibody pretreatment. Activation of peroxisome proliferator-activated receptor (PPAR)-{gamma} was evident in BACs with ox-LDL addition and was attenuated by anti-LOX-1 antibody. The specific PPAR-{gamma} inhibitor GW9662more » suppressed ox-LDL-induced VEGF expression. These results suggest that the ox-LDL/LOX-1 system upregulates VEGF expression in articular cartilage, at least in part, through activation of PPAR-{gamma} and supports the hypothesis that ox-LDL is involved in cartilage degradation via LOX-1.« less

Down-regulation of Jab1, HIF-1alpha, and VEGF by Moloney murine leukemia virus-ts1 infection: a possible cause of neurodegeneration.

PubMed

Lungu, Gina F; Stoica, George; Wong, Paul K Y

2008-05-01

Moloney murine leukemia virus-temperature sensitive (MoMuLV-ts1)-mediated neuronal death is a result of both loss of glial support and release of cytokines and neurotoxins from ts1-infected glial cells. Here the authors propose vascular endothelial growth factor (VEGF) down-regulation as another contributory factor in neuronal degeneration induced by ts1 infection. To determine how ts1 affects VEGF expression in ts1-infected brain, the authors examined the expression of several proteins that are important in regulating the expression of VEGF. The authors found significant decreases in Jun-activating domain-binding protein 1 (Jab1), hypoxia-inducible factor (HIF)-1alpha, and VEGF levels and increases in p53 protein levels in ts1-infected brains compared to noninfected control brains. The authors suggest that a decrease Jab1 expression in ts1 infection leads to accumulation of p53, which binds to HIF-1alpha to accelerate its degradation. A rapid degradation of HIF-1alpha leads to decreased VEGF production and secretion. Considering that endothelial cells are the most conspicuous in virus replication and production in ts1 infection, but are not killed by the infection, the authors examined the expression of these proteins using infected and noninfected mouse cerebrovascular endothelial (CVE) cells. The ts1- infected CVE cells showed decreased Jab1, HIF-1alpha, and VEGF mRNA and protein levels and increased p53 protein levels compared with noninfected cells, consistent with the results found in vivo. These results confirm that ts1 infection results in insufficient secretion of VEGF from endothelial cells and may result in decreased neuroprotection. This study suggested that ts1-mediated neuropathology in mice may result from changes in expression and activity of Jab1, p53, and HIF-1alpha, with a final target on VEGF expression and neuronal degeneration.

Development of a Sustainable Release System for a Ranibizumab Biosimilar Using Poly(lactic-co-glycolic acid) Biodegradable Polymer-Based Microparticles as a Platform.

PubMed

Tanetsugu, Yusuke; Tagami, Tatsuaki; Terukina, Takayuki; Ogawa, Takaya; Ohta, Masato; Ozeki, Tetsuya

2017-01-01

Ranibizumab is a humanized monoclonal antibody fragment against vascular endothelial growth factor (VEGF)-A and is widely used to treat age-related macular degeneration (AMD) caused by angiogenesis. Ranibizumab has a short half-life in the eye due to its low molecular weight and susceptibility to proteolysis. Monthly intravitreal injection of a large amount of ranibizumab formulation is a burden for both patients and medical staff. We therefore sought to develop a sustainable release system for treating the eye with ranibizumab using a drug carrier. A ranibizumab biosimilar (RB) was incorporated into microparticles of poly(lactic-co-glycolic acid) (PLGA) biodegradable polymer. Ranibizumab was sustainably released from PLGA microparticles (80+% after 3 weeks). Assay of tube formation by endothelial cells indicated that RB released from PLGA microparticles inhibited VEGF-induced tube formation and this tendency was confirmed by a cell proliferation assay. These results indicate that RB-loaded PLGA microparticles are useful for sustainable RB release and suggest the utility of intraocular sustainable release systems for delivering RB site-specifically to AMD patients.

Drug depot-anchoring hydrogel: A self-assembling scaffold for localized drug release and enhanced stem cell differentiation.

PubMed

Li, Ruixiang; Pang, Zhiqing; He, Huining; Lee, Seungjin; Qin, Jing; Wu, Jian; Pang, Liang; Wang, Jianxin; Yang, Victor C

2017-09-10

Localized and long-term delivery of growth factors has been a long-standing challenge for stem cell-based tissue engineering. In the current study, a polymeric drug depot-anchoring hydrogel scaffold was developed for the sustained release of macromolecules to enhance the differentiation of stem cells. Self-assembling peptide (RADA16)-modified drug depots (RDDs) were prepared and anchored to a RADA16 hydrogel. The anchoring effect of RADA16 modification on the RDDs was tested both in vitro and in vivo. It was shown that the in vitro leakage of RDDs from the RADA16 hydrogel was significantly less than that of the unmodified drug depots (DDs). In addition, the in vivo retention of injected hydrogel-incorporated RDDs was significantly longer than that of hydrogel-incorporated unmodified DDs. A model drug, vascular endothelial growth factor (VEGF), was encapsulated in RDDs (V-RDDs) as drug depot that was then anchored to the hydrogel. The release of VEGF could be sustained for 4weeks. Endothelial progenitor cells (EPCs) were cultured on the V-RDDs-anchoring scaffold and enhanced cell proliferation and differentiation were observed, compared with a VEGF-loaded scaffold. Furthermore, this scaffold laden with EPCs promoted neovascularization in an animal model of hind limb ischemia. These results demonstrate that self-assembling hydrogel-anchored drug-loaded RDDs are promising for localized and sustained drug release, and can effectively enhance the proliferation and differentiation of resident stem cells, thus lead to successful tissue regeneration. Copyright © 2017. Published by Elsevier B.V.

Microparticles released by vascular endothelial cells increase hypoxia inducible factor expression in human proximal tubular HK-2 cells.

PubMed

Fernandez-Martínez, Ana Belen; Torija, Ana Valdehita; Carracedo, Julia; Ramirez, Rafael; de Lucio-Cazaña, Francisco Javier

2014-08-01

Microparticles are produced by vesiculation of the cell plasma membrane and serve as vectors of cell-to-cell communication. Co-culture experiments have shown that hypoxia-inducible factor-α (HIF-α)-regulated-genes are up-regulated in human renal proximal tubular HK-2 cells by endothelial cell factors which might be transported inside endothelial microparticles (EMP). Here we aimed to study in HK-2 cells the effect of EMP, produced by activated endothelial cells, on HIF-α and HIF-α-regulated vascular endothelial growth factor-A (VEGF-A). EMP, at a concentration much lower than that found in plasma, increased the expression of HIF-α/VEGF-A in a COX-2/EP2 receptor dependent manner. Since the EMP/cells ratio was ∼1/1000, we hypothesized that paracrine mediators produced by HK-2 cells amplified the initial signal. This hypothesis was confirmed by two facts which also suggested that the mediators were conveyed by particles released by HK-2 cells: (i) HIF-α was up-regulated in HK-2 cells treated with the pellet obtained from the conditioned medium of the EMP-treated HK-2 cells. (ii) In transwell experiments, EMP-treated cells increased the expression of HIF-α in untreated HK-2 cells. Interestingly, we detected these cells, particles that were released by EMP-treated HK-2 cells. Depending on the pathological context, activation of HIF-α and VEGF-A signaling in renal tissue/cells may have either beneficial or harmful effects. Therefore, our results suggest that their presence in the urinary space of EMP produced by activated endothelial cells may influence the outcome of a number of renal diseases. Copyright © 2014 Elsevier Ltd. All rights reserved.

Angiotensin II Evokes Angiogenic Signals within Skeletal Muscle through Co-ordinated Effects on Skeletal Myocytes and Endothelial Cells

PubMed Central

Gorman, Jennifer L.; Liu, Sammy T. K.; Slopack, Dara; Shariati, Khashayar; Hasanee, Adam; Olenich, Sara; Olfert, I. Mark; Haas, Tara L.

2014-01-01

Skeletal muscle overload induces the expression of angiogenic factors such as vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)-2, leading to new capillary growth. We found that the overload-induced increase in angiogenesis, as well as increases in VEGF, MMP-2 and MT1-MMP transcripts were abrogated in muscle VEGF KO mice, highlighting the critical role of myocyte-derived VEGF in controlling this process. The upstream mediators that contribute to overload-induced expression of VEGF have yet to be ascertained. We found that muscle overload increased angiotensinogen expression, a precursor of angiotensin (Ang) II, and that Ang II signaling played an important role in basal VEGF production in C2C12 cells. Furthermore, matrix-bound VEGF released from myoblasts induced the activation of endothelial cells, as evidenced by elevated endothelial cell phospho-p38 levels. We also found that exogenous Ang II elevates VEGF expression, as well as MMP-2 transcript levels in C2C12 myotubes. Interestingly, these responses also were observed in skeletal muscle endothelial cells in response to Ang II treatment, indicating that these cells also can respond directly to the stimulus. The involvement of Ang II in muscle overload-induced angiogenesis was assessed. We found that blockade of AT1R-dependent Ang II signaling using losartan did not attenuate capillary growth. Surprisingly, increased levels of VEGF protein were detected in overloaded muscle from losartan-treated rats. Similarly, we observed elevated VEGF production in cultured endothelial cells treated with losartan alone or in combination with Ang II. These studies conclusively establish the requirement for muscle derived VEGF in overload-induced angiogenesis and highlight a role for Ang II in basal VEGF production in skeletal muscle. However, while Ang II signaling is activated following overload and plays a role in muscle VEGF production, inhibition of this pathway is not sufficient to halt overload-induced angiogenesis, indicating that AT1-independent signals maintain VEGF production in losartan-treated muscle. PMID:24416421

Bone engineering in dog mandible: Coculturing mesenchymal stem cells with endothelial progenitor cells in a composite scaffold containing vascular endothelial growth factor.

PubMed

Khojasteh, Arash; Fahimipour, Farahnaz; Jafarian, Mohammad; Sharifi, Davoud; Jahangir, Shahrbanoo; Khayyatan, Fahimeh; Baghaban Eslaminejad, Mohamadreza

2017-10-01

We sought to assess the effects of coculturing mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) in the repair of dog mandible bone defects. The cells were delivered in β-tricalcium phosphate scaffolds coated with poly lactic co-glycolic acid microspheres that gradually release vascular endothelial growth factor (VEGF). The complete scaffold and five partial scaffolds were implanted in bilateral mandibular body defects in eight beagles. The scaffolds were examined histologically and morphometrically 8 weeks after implantation. Histologic staining of the decalcified scaffolds demonstrated that bone formation was greatest in the VEGF/MSC scaffold (63.42 ± 1.67), followed by the VEGF/MSC/EPC (47.8 ± 1.87) and MSC/EPC (45.21 ± 1.6) scaffolds, the MSC scaffold (34.59 ± 1.49), the VEGF scaffold (20.03 ± 1.29), and the untreated scaffold (7.24 ± 0.08). Hence, the rate of new bone regeneration was highest in scaffolds containing MSC, either mixed with EPC or incorporating VEGF. Adding both EPC and VEGF with the MSC was not necessary. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1767-1777, 2017. © 2016 Wiley Periodicals, Inc.

Expression Pattern of HIF-1α and VEGF Supports Circumferential Application of Scatter Laser for Proliferative Sickle Retinopathy

PubMed Central

Rodrigues, Murilo; Kashiwabuchi, Fabiana; Deshpande, Monika; Jee, Kathleen; Goldberg, Morton F.; Lutty, Gerard; Semenza, Gregg L.; Montaner, Silvia; Sodhi, Akrit

2016-01-01

Purpose Retinal vascular occlusions in sickle cell anemia patients cause tissue ischemia and the release of angiogenic mediators that promote the development of retinal neovascularization, initiating proliferative sickle retinopathy (PSR). Laser photocoagulation (LPC) has emerged as the most common treatment for PSR. Nonetheless, only two randomized controlled clinical trials have evaluated the use of LPC for PSR, and both failed to definitively demonstrate efficacy of this approach. This may be due to a lack of knowledge regarding the appropriate location for placement of laser coagulations in PSR eyes. To help address this question, we examined the expression of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) in PSR eyes. Methods The expression pattern of HIF-1α and VEGF in PSR (n = 5) and control (n = 3) eyes was examined by immunohistochemistry in different retinal regions defined by the presence or absence of retinal vessels. Results Hypoxia-inducible factor 1α and VEGF were expressed in the inner retina of 5/5 untreated PSR eyes adjacent to retinal neovascularization; expression of HIF-1α was not detected (and VEGF only lightly detected) in normal retinal and choroidal vasculature of 3/3 control eyes. Hypoxia-inducible factor 1α and VEGF were strongly expressed in retinal cells within avascular (nonperfused) retina, anterior to the boundary between perfused and nonperfused retina, as well as in posterior ischemic retina in the presence or absence of neovascular sea fans. Conclusions If the goal of LPC in PSR is to quench the expression of HIF-1–driven angiogenic mediators, our results support broad application of peripheral laser for its treatment. PMID:27951596

PKCδ Regulates Force Signaling during VEGF/CXCL4 Induced Dissociation of Endothelial Tubes

PubMed Central

Jamison, Joshua; Wang, James H-C.; Wells, Alan

2014-01-01

Wound healing requires the vasculature to re-establish itself from the severed ends; endothelial cells within capillaries must detach from neighboring cells before they can migrate into the nascent wound bed to initiate angiogenesis. The dissociation of these endothelial capillaries is driven partially by platelets' release of growth factors and cytokines, particularly the chemokine CXCL4/platelet factor-4 (PF4) that increases cell-cell de-adherence. As this retraction is partly mediated by increased transcellular contractility, the protein kinase c-δ/myosin light chain-2 (PKCδ/MLC-2) signaling axis becomes a candidate mechanism to drive endothelial dissociation. We hypothesize that PKCδ activation induces contractility through MLC-2 to promote dissociation of endothelial cords after exposure to platelet-released CXCL4 and VEGF. To investigate this mechanism of contractility, endothelial cells were allowed to form cords following CXCL4 addition to perpetuate cord dissociation. In this study, CXCL4-induced dissociation was reduced by a VEGFR inhibitor (sunitinib malate) and/or PKCδ inhibition. During combined CXCL4+VEGF treatment, increased contractility mediated by MLC-2 that is dependent on PKCδ regulation. As cellular force is transmitted to focal adhesions, zyxin, a focal adhesion protein that is mechano-responsive, was upregulated after PKCδ inhibition. This study suggests that growth factor regulation of PKCδ may be involved in CXCL4-mediated dissociation of endothelial cords. PMID:24699667

PKCδ regulates force signaling during VEGF/CXCL4 induced dissociation of endothelial tubes.

PubMed

Jamison, Joshua; Wang, James H-C; Wells, Alan

2014-01-01

Wound healing requires the vasculature to re-establish itself from the severed ends; endothelial cells within capillaries must detach from neighboring cells before they can migrate into the nascent wound bed to initiate angiogenesis. The dissociation of these endothelial capillaries is driven partially by platelets' release of growth factors and cytokines, particularly the chemokine CXCL4/platelet factor-4 (PF4) that increases cell-cell de-adherence. As this retraction is partly mediated by increased transcellular contractility, the protein kinase c-δ/myosin light chain-2 (PKCδ/MLC-2) signaling axis becomes a candidate mechanism to drive endothelial dissociation. We hypothesize that PKCδ activation induces contractility through MLC-2 to promote dissociation of endothelial cords after exposure to platelet-released CXCL4 and VEGF. To investigate this mechanism of contractility, endothelial cells were allowed to form cords following CXCL4 addition to perpetuate cord dissociation. In this study, CXCL4-induced dissociation was reduced by a VEGFR inhibitor (sunitinib malate) and/or PKCδ inhibition. During combined CXCL4+VEGF treatment, increased contractility mediated by MLC-2 that is dependent on PKCδ regulation. As cellular force is transmitted to focal adhesions, zyxin, a focal adhesion protein that is mechano-responsive, was upregulated after PKCδ inhibition. This study suggests that growth factor regulation of PKCδ may be involved in CXCL4-mediated dissociation of endothelial cords.

Induction of endothelial cell proliferation by angiogenic factors released by activated monocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pakala, Rajbabu; Watanabe, Takuya; Benedict, Claude R

2002-06-01

Introduction: Cell-cell interaction is an essential component of atherosclerotic plaque development. Activated monocytes appear to play a central role in the development of atherosclerosis, not only through foam cell formation but also via the production of various growth factors that induce proliferation of different cell types that are involved in the plaque development. Using serum free co-culture method, we determined the effect of monocytes on endothelial cell proliferation. Methods: Endothelial cell proliferation is determined by the amount of [{sup 3}H]thymidine incorporated in to the DNA. Basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) levels inmore » the conditioned medium were determined by ELISA. Results: Conditioned medium from unactivated monocytes partially inhibited endothelial cell proliferation, whereas conditioned medium from activated monocytes promoted endothelial cell proliferation. The mitogenic effect of conditioned medium derived from activated monocytes is due to the presence of b-FGF, VEGF and IL-8. Neutralizing antibodies against b-FGF, VEGF and IL-8 partially reversed the mitogenic effect of conditioned medium derived from activated monocytes. When b-FGF, VEGF and IL-8 were immunoprecipitated from conditioned medium derived from activated monocytes, it is less mitogenic to endothelial cells. Conclusion: Activated monocytes may play an important role in the development of atherosclerotic plaque by producing endothelial cell growth factors.« less

Silk hydrogels for sustained ocular delivery of anti-vascular endothelial growth factor (anti-VEGF) therapeutics.

PubMed

Lovett, Michael L; Wang, Xiaoqin; Yucel, Tuna; York, Lyndsey; Keirstead, Marc; Haggerty, Linda; Kaplan, David L

2015-09-01

Silk hydrogels were formulated with anti-vascular endothelial growth factor (anti-VEGF) therapeutics for sustained ocular drug delivery. Using silk fibroin as a vehicle for delivery, bevacizumab-loaded hydrogel formulations demonstrated sustained release of 3 months or greater in experiments in vitro as well as in vivo using an intravitreal injection model in Dutch-belted rabbits. Using both standard dose (1.25mg bevacizumab/50 μL injection) and high dose (5.0mg bevacizumab/50 μL injection) hydrogel formulations, release concentrations were achieved at day 90 that were equivalent or greater than those achieved at day 30 with the positive standard dose control (single injection (50 μL) of 1.25mg bevacizumab solution), which is estimated to be the therapeutic threshold based on the current dosage administration schedule of 1 injection/month. These gels also demonstrated signs of biodegradation after 3 months, suggesting that repeated injections may be possible (e.g., one injection every 3-6 months or longer). Due to its pharmacokinetic and biodegradation profiles, this delivery system may be used to reduce the frequency of dosing for patients currently enduring treatment using bevacizumab or other anti-VEGF therapeutics. Copyright © 2015 Elsevier B.V. All rights reserved.

Role of platelet-released growth factors in detoxification of reactive oxygen species in osteoblasts.

PubMed

Tohidnezhad, Mersedeh; Wruck, Christoph-Jan; Slowik, Alexander; Kweider, Nisreen; Beckmann, Rainer; Bayer, Andreas; Houben, Astrid; Brandenburg, Lars-Ove; Varoga, Deike; Sönmez, Tolga-Taha; Stoffel, Marcus; Jahr, Holger; Lippross, Sebastian; Pufe, Thomas

2014-08-01

Oxidative stress can impair fracture healing. To protect against oxidative damage, a system of detoxifying and antioxidative enzymes works to reduce the cellular stress. The transcription of these enzymes is regulated by antioxidant response element (ARE). The nuclear factor (erythroid-derived 2)-like2 (Nrf2) plays a major role in transcriptional activation of ARE-driven genes. Recently it has been shown that vascular endothelial growth factor (VEGF) prevents oxidative damage via activation of the Nrf2 pathway in vitro. Platelet-released growth factor (PRGF) is a mixture of autologous proteins and growth factors, prepared from a determined volume of platelet-rich plasma (PRP). It has already used to enhance fracture healing in vitro. The aim of the present study was to elucidate if platelets can lead to upregulation of VEGF and if platelets can regulate the activity of Nrf2-ARE system in primary human osteoblast (hOB) and in osteoblast-like cell line (SAOS-2). Platelets and PRGF were obtained from healthy human donors. HOB and SAOS-2 osteosarcoma cell line were used. The ARE activity was analysed using a dual luciferase reporter assay system. We used Western blot to detect the nuclear accumulation of Nrf2 and the amount of cytosolic antioxidant Thioredoxin Reductase-1 (TXNRD-1), Heme Oxygenase-1 (HO-1) and NAD(P)H quinine oxidoreductase-1 (NQO1). Gene expression analysis was performed by real-time RT PCR. ELISA was used for the quantification of growth factors. The activity of ARE was increased in the presence of PRGF up to 50%. Western blotting demonstrated enhanced nuclear accumulation of Nrf2. This was followed by an increase in the protein expression of the aforementioned downstream targets of Nrf2. Real-time RT PCR data showed an upregulation in the gene expression of the VEGF after PRGF treatment. This was confirmed by ELISA, where the treatment with PRGF induced the protein level of VEGF in both cells. These results provide a new insight into PRGF's mode of action in osteoblasts. PRGF not only leads to increase the endogenous VEGF, but also it may be involved in preventing oxidative damage through the Nrf2-ARE signalling. Nrf2 activation via PRGF may have great potential as an effective therapeutic drug target in fracture healing. Copyright © 2014 Elsevier Inc. All rights reserved.

Platelet-rich concentrates differentially release growth factors and induce cell migration in vitro.

PubMed

Schär, Michael O; Diaz-Romero, Jose; Kohl, Sandro; Zumstein, Matthias A; Nesic, Dobrila

2015-05-01

Platelet-rich concentrates are used as a source of growth factors to improve the healing process. The diverse preparation protocols and the gaps in knowledge of their biological properties complicate the interpretation of clinical results. In this study we aimed to (1) analyze the concentration and kinetics of growth factors released from leukocyte- and platelet-rich fibrin (L-PRF), leukocyte- and platelet-rich plasma (L-PRP), and natural blood clot during in vitro culture; (2) investigate the migration of mesenchymal stem cells (MSCs) and human umbilical vein endothelial cells (HUVECs) as a functional response to the factors released; and (3) uncover correlations between individual growth factors with the initial platelet/leukocyte counts or the induced cell migration. L-PRF, L-PRP, and natural blood clot prepared from 11 donors were cultured in vitro for 28 days and media supernatants collected after 8 hours and 1, 3, 7, 14, and 28 days. Released transforming growth factor β1 (TGF-β1), vascular endothelial growth factor (VEGF), insulin growth factor (IGF-1), platelet-derived growth factor AB (PDGF-AB), and interleukin-1β (IL-1β) were measured in the supernatants with enzyme-linked immunosorbent assay. Migration of MSC and HUVEC induced by the supernatants was evaluated in Boyden chambers. More TGF-ß1 was released (mean ± SD in pg/mL of blood) from L-PRF (37,796 ± 5492) compared with L-PRP (23,738 ± 6848; p < 0.001) and blood clot (3739 ± 4690; p < 0.001), whereas more VEGF and IL-1ß were released from blood clot (1933 ± 704 and 2053 ± 908, respectively) compared with both L-PRP (642 ± 208; p < 0.001 and 273 ± 386; p < 0.001, respectively) and L-PRF (852 ± 376; p < 0.001 and 65 ± 56, p < 0.001, respectively). No differences were observed in IGF-1 and PDGF-AB released from any of the concentrates. TGF-β1 release peaked at Day 7 in L-PRF and at 8 hours and Day 7 in L-PRP and 8 hours and Day 14 in blood clot. In all concentrates, main release of VEGF occurred between 3 and 7 days and of IL-1β between Days 1 and 7. IGF-1 and PDGF-AB were released until Day 1 in L-PRP and blood clot, in contrast to sustained release over the first 3 days in L-PRF. The strongest migration of MSC occurred in response to L-PRF, and more HUVEC migration was seen in L-PRF and blood clot compared with L-PRP. TGF-β1 correlated with initial platelet counts in L-PRF (Pearson r = 0.66, p = 0.0273) and initial leukocyte counts in L-PRP (Pearson r = 0.83, p = 0.0016). A positive correlation of IL-1β on migration of MSC and HUVEC was revealed (Pearson r = 0.16, p = 0.0208; Pearson r = 0.31, p < 0.001). In comparison to L-PRP, L-PRF had higher amounts of released TGF-β1, a long-term release of growth factors, and stronger induction of cell migration. Future preclinical studies should confirm these data in a defined injury model. By characterizing the biologic properties of different platelet concentrates in vitro, we may gain a better understanding of their clinical effects and develop guidelines for specific future applications.

Low grade inflammation inhibits VEGF induced HUVECs migration in p53 dependent manner

DOE Office of Scientific and Technical Information (OSTI.GOV)

Panta, Sushil; Yamakuchi, Munekazu; Kagoshima University Hospital, Kagoshima

In the course of studying crosstalk between inflammation and angiogenesis, high doses of pro-inflammatory factors have been reported to induce apoptosis in cells. Under normal circumstances also the pro-inflammatory cytokines are being released in low doses and are actively involved in cell signaling pathways. We studied the effects of low grade inflammation in growth factor induced angiogenesis using tumor necrosis factor alfa (TNFα) and vascular endothelial growth factor A (VEGF) respectively. We found that low dose of TNFα can inhibit VEGF induced angiogenesis in human umbilical vein endothelial cells (HUVECs). Low dose of TNFα induces mild upregulation and moreover nuclearmore » localization of tumor suppressor protein 53 (P53) which causes decrease in inhibitor of DNA binding-1 (Id1) expression and shuttling to the cytoplasm. In absence of Id1, HUVECs fail to upregulate β{sub 3}-integrin and cell migration is decreased. Connecting low dose of TNFα induced p53 to β{sub 3}-integrin through Id1, we present additional link in cross talk between inflammation and angiogenesis. - Highlights: • Low grade inflammation (low dose of TNF alfa) inhibits VEGF induced endothelial cells migration. • The low grade inflammation with VEGF treatment upregulates P53 to a nonlethal level. • P53 activation inhibits Id1 shuttling to the cytoplasm in endothelial cells. • Inhibition of Id1 resulted in downregulation of β{sub 3}-integrin which cause decrease in cell migration. • Inflammation and angiogenesis might cross-talk by P53 – Id1 – β{sub 3}-integrin pathway in endothelial cells.« less

Peroxynitrite Upregulates Angiogenic Factors VEGF-A, BFGF, and HIF-1α in Human Corneal Limbal Epithelial Cells

PubMed Central

Ashki, Negin; Chan, Ann M.; Qin, Yu; Wang, Wei; Kiyohara, Meagan; Lin, Lin; Braun, Jonathan; Wadehra, Madhuri; Gordon, Lynn K.

2014-01-01

Purpose. Corneal neovascularization (NV) is a sight-threatening condition often associated with infection, inflammation, prolonged contact lens use, corneal burns, and acute corneal graft rejection. Macrophages recruited to the cornea release nitric oxide (NO) and superoxide anion (O2−), which react together to form the highly toxic molecule peroxynitrite (ONOO−). The role of ONOO− in upregulating multiple angiogenic factors in cultured human corneal limbal epithelial (HCLE) cells was investigated. Methods. Human corneal limbal epithelial cells were incubated with 500 μM of ONOO− donor for various times. VEGF-A, BFGF, and hypoxic-inducible factor-alpha (HIF-1α) were investigated via Western blot and RT-PCR was performed for VEGF. Functional assays using human umbilical vein endothelial cells (HUVEC) used conditioned media from ONOO−-exposed HCLE cells. Secreted VEGF from conditioned media was detected and analyzed using ELISA. Results. Increased angiogenic factors were observed as early as 4 hours after HCLE exposure to ONOO−. HIF-1 expression was seen at 4, 6, and 8 hours post-ONOO− exposure (P < 0.05). BFGF expression was elevated at 4 hours and peaked at 8 hours after treatment with ONOO− (P < 0.005). Increased VEGF-A gene expression was observed at 6 and 8 hours post-ONOO− treatment. Functional assays using conditioned media showed increased HUVEC migration and tube formation. Conclusions. Exposure to elevated extracellular concentrations of ONOO− results in upregulation of angiogenic factors in HCLE cells. It is possible that, in the setting of inflammation or infection, that exposure to ONOO− could be one contributor to the complex initiators of corneal NV. Validation in vivo would identify an additional potential control point for corneal NV. PMID:24398102

Peroxynitrite upregulates angiogenic factors VEGF-A, BFGF, and HIF-1α in human corneal limbal epithelial cells.

PubMed

Ashki, Negin; Chan, Ann M; Qin, Yu; Wang, Wei; Kiyohara, Meagan; Lin, Lin; Braun, Jonathan; Wadehra, Madhuri; Gordon, Lynn K

2014-03-19

Corneal neovascularization (NV) is a sight-threatening condition often associated with infection, inflammation, prolonged contact lens use, corneal burns, and acute corneal graft rejection. Macrophages recruited to the cornea release nitric oxide (NO) and superoxide anion (O2(-)), which react together to form the highly toxic molecule peroxynitrite (ONOO(-)). The role of ONOO(-) in upregulating multiple angiogenic factors in cultured human corneal limbal epithelial (HCLE) cells was investigated. Human corneal limbal epithelial cells were incubated with 500 μM of ONOO(-) donor for various times. VEGF-A, BFGF, and hypoxic-inducible factor-alpha (HIF-1α) were investigated via Western blot and RT-PCR was performed for VEGF. Functional assays using human umbilical vein endothelial cells (HUVEC) used conditioned media from ONOO(-)-exposed HCLE cells. Secreted VEGF from conditioned media was detected and analyzed using ELISA. Increased angiogenic factors were observed as early as 4 hours after HCLE exposure to ONOO(-). HIF-1 expression was seen at 4, 6, and 8 hours post-ONOO(-) exposure (P < 0.05). BFGF expression was elevated at 4 hours and peaked at 8 hours after treatment with ONOO(-) (P < 0.005). Increased VEGF-A gene expression was observed at 6 and 8 hours post-ONOO(-) treatment. Functional assays using conditioned media showed increased HUVEC migration and tube formation. Exposure to elevated extracellular concentrations of ONOO(-) results in upregulation of angiogenic factors in HCLE cells. It is possible that, in the setting of inflammation or infection, that exposure to ONOO(-) could be one contributor to the complex initiators of corneal NV. Validation in vivo would identify an additional potential control point for corneal NV.

The effects of biomimetically conjugated VEGF on osteogenesis and angiogenesis of MSCs (human and rat) and HUVECs co-culture models.

PubMed

Lü, Lanxin; Deegan, Anthony; Musa, Faiza; Xu, Tie; Yang, Ying

2018-07-01

The purpose of this work was to investigate if the biomimetically conjugated VEGF and HUVECs co-culture could modulate the osteogenic and angiogenic differentiation of MSCs derived from rat and human bone marrow (rMSCs and hMSCs). After treated by ammonia plasma, Poly(lactic-co-glycolic acid) (PLGA) electrospun nanofibers were immobilized with VEGF through heparin to fulfil the sustained release. The proliferation capacity of rMSCs and hMSCs on neat PLGA nanofibers (NF) and VEGF immobilized NF (NF-VEGF) surfaces were assessed by CCK-8 and compared when MSCs were mono-cultured and co-cultured with HUVECs. The effect of VEGF and HUVECs co-culturing on osteogenic and angiogenic differentiation of rMSCs and hMSCs were investigated by calcium deposits and CD31 expression on NF and NF-VEGF surfaces. The results indicated that VEGF has been biomimetically immobilized onto PLGA nanofibers surface and kept sustained release successfully. The CD31 staining results showed that both VEGF and HUVECs co-culture could enhance the angiogenesis of rMSCs and hMSCs. However, the proliferation and osteogenic differentiation of MSCs when cultured with VEGF and HUVECs showed a species dependent response. Taken together, VEGF immobilization and co-culture with HUVECs promoted angiogenesis of MSCs, indicating a good strategy for vascularization in bone tissue engineering. Copyright © 2018. Published by Elsevier B.V.

Oncogenic RAS pathway activation promotes resistance to anti-VEGF therapy through G-CSF–induced neutrophil recruitment

PubMed Central

Phan, Vernon T.; Wu, Xiumin; Cheng, Jason H.; Sheng, Rebecca X.; Chung, Alicia S.; Zhuang, Guanglei; Tran, Christopher; Song, Qinghua; Kowanetz, Marcin; Sambrone, Amy; Tan, Martha; Meng, Y. Gloria; Jackson, Erica L.; Peale, Franklin V.; Junttila, Melissa R.; Ferrara, Napoleone

2013-01-01

Granulocyte-colony stimulating factor (G-CSF) promotes mobilization of CD11b+Gr1+ myeloid cells and has been implicated in resistance to anti-VEGF therapy in mouse models. High G-CSF production has been associated with a poor prognosis in cancer patients. Here we show that activation of the RAS/MEK/ERK pathway regulates G-CSF expression through the Ets transcription factor. Several growth factors induced G-CSF expression by a MEK-dependent mechanism. Inhibition of G-CSF release with a MEK inhibitor markedly reduced G-CSF production in vitro and synergized with anti-VEGF antibodies to reduce CD11b+Ly6G+ neutrophil mobilization and tumor growth and led to increased survival in animal models of cancer, including a genetically engineered mouse model of pancreatic adenocarcinoma. Analysis of biopsies from pancreatic cancer patients revealed increased phospho-MEK, G-CSF, and Ets expression and enhanced neutrophil recruitment compared with normal pancreata. These results provide insights into G-CSF regulation and on the mechanism of action of MEK inhibitors and point to unique anticancer strategies. PMID:23530240

Inhibition of vascular endothelial growth factor-induced angiogenesis suppresses tumour growth in vivo

NASA Astrophysics Data System (ADS)

Kim, K. Jin; Li, Bing; Winer, Jane; Armanini, Mark; Gillett, Nancy; Phillips, Heidi S.; Ferrara, Napoleone

1993-04-01

THE development of new blood vessels (angiogenesis) is required for many physiological processes including embryogenesis, wound healing and corpus luteum formation1,2. Blood vessel neoformation is also important in the pathogenesis of many disorders1-5, particularly rapid growth and metastasis of solid tumours3-5. There are several potential mediators of tumour angiogenesis, including basic and acidic fibroblast growth factors, tumour necrosis factor-α and transforming factors-α and -β 1,2. But it is unclear whether any of these agents actually mediates angiogenesis and tumour growth in vivo. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen and an angiogenesis inducer released by a variety of tumour cells and expressed in human tumours in situ. To test whether VEGF may be a tumour angiogenesis factor in vivo, we injected human rhabdomyosar-coma, glioblastoma multiforme or leiomyosarcoma cell lines into nude mice. We report here that treatment with a monoclonal antibody specific for VEGF inhibited the growth of the tumours, but had no effect on the growth rate of the tumour cells In vitro. The density of vessels was decreased in the antibody-treated tumours. These findings demonstrate that inhibition of the action of an angiogenic factor spontaneously produced by tumour cells may suppress tumour growth in vivo.

Toll-like receptor 2 mediates mesenchymal stem cell-associated myocardial recovery and VEGF production following acute ischemia-reperfusion injury

PubMed Central

Abarbanell, Aaron M.; Wang, Yue; Herrmann, Jeremy L.; Weil, Brent R.; Poynter, Jeffrey A.; Manukyan, Mariuxi C.

2010-01-01

Toll-like receptor 2 (TLR2), a key component of the innate immune system, is linked to inflammation and myocardial dysfunction after ischemia-reperfusion injury (I/R). Treatment of the heart with mesenchymal stem cells (MSCs) is known to improve myocardial recovery after I/R in part by paracrine factors such as VEGF. However, it is unknown whether TLR2 activation on the MSCs affects MSC-mediated myocardial recovery and VEGF production. We hypothesized that the knockout of TLR2 on the MSCs (TLR2KO MSCs) would 1) improve MSC-mediated myocardial recovery and 2) increase myocardial and MSC VEGF release. With the isolated heart perfusion system, Sprague-Dawley rat hearts were subjected to I/R and received one of three intracoronary treatments: vehicle, male wild-type MSCs (MWT MSCs), or TL2KO MSCs. All treatments were performed immediately before ischemia, and heart function was measured continuously. Postreperfusion, heart homogenates were analyzed for myocardial VEGF production. Contrary to our hypothesis, only MWT MSC treatment significantly improved the recovery of left ventricular developed pressure and the maximal positive and negative values of the first derivative of pressure. In addition, VEGF production was greatest in hearts treated with MWT MSCs. To investigate MSC production of VEGF, MSCs were activated with TNF in vitro and the supernatants collected for ELISA. In vitro basal levels of MSC VEGF production were similar. However, with TNF activation, MWT MSCs produced significantly more VEGF, whereas activated TLR2KO MSC production of VEGF was unchanged. Finally, we observed that MWT MSCs proliferated more rapidly than TLR2KO MSCs. These data indicate that TLR2 may be essential to MSC-mediated myocardial recovery and VEGF production. PMID:20173040

Resveratrol attenuates myocardial ischemia/reperfusion injury through up-regulation of vascular endothelial growth factor B.

PubMed

Yang, Lei; Zhang, Yan; Zhu, Mengmeng; Zhang, Qiong; Wang, Xiaoling; Wang, Yanjiao; Zhang, Jincai; Li, Jing; Yang, Liang; Liu, Jie; Liu, Fei; Yang, Yinan; Kang, Licheng; Shen, Yanna; Qi, Zhi

2016-12-01

The objective was to examine the protective effect of resveratrol (RSV) on myocardial ischemia/reperfusion (IR) injury and whether the mechanism was related to vascular endothelial growth factor B (VEGF-B) signaling pathway. Rat hearts were isolated for Langendorff perfusion test and H9c2 cells were used for in vitro assessments. RSV treatment significantly improved left ventricular function, inhibited CK-MB release, and reduced infarct size in comparison with IR group ex vivo. RSV treatment markedly decreased cell death and apoptosis of H9c2 cells during IR. We found that RSV was responsible for the up-regulation of VEGF-B mRNA and protein level, which caused the activation of Akt and the inhibition of GSK3β. Additionally, RSV prevented the generation of reactive oxygen species (ROS) by up-regulating the expression of MnSOD either in vitro or ex vivo. We also found that the inhibition of VEGF-B abolished the cardioprotective effect of RSV, increased apoptosis, and led to the down-regulation of phosphorylated Akt, GSK3β, and MnSOD in H9c2 cells. These results demonstrated that RSV was able to attenuate myocardial IR injury via promotion of VEGF-B/antioxidant signaling pathway. Therefore, the up-regulation of VEGF-B can be a promising modality for clinical myocardial IR injury therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Hypoxia and inflammation in the release of VEGF and interleukins from human retinal pigment epithelial cells.

PubMed

Arjamaa, Olli; Aaltonen, Vesa; Piippo, Niina; Csont, Tamás; Petrovski, Goran; Kaarniranta, Kai; Kauppinen, Anu

2017-09-01

Retinal diseases are closely associated with both decreased oxygenation and increased inflammation. It is not known if hypoxia-induced vascular endothelial growth factor (VEGF) expression in the retina itself evokes inflammation, or whether inflammation is a prerequisite for the development of neovascularization. Human ARPE-19 cell line and primary human retinal pigment epithelium (RPE) cells were used. ARPE-19 cells were kept either under normoxic (24 h or 48 h) or hypoxic conditions (1% O 2 , 24 h). Part of the cells were re-oxygenated (24 h). Some ARPE-19 cells were additionally pre-treated with bacterial lipopolysaccharide (LPS). The levels of IL-6, IL-8, IL-1β, and IL-18 were determined from medium samples by an enzyme-linked immunosorbent assay (ELISA) method. Primary human RPE cells were exposed to hypoxia for 24 h, and the subsequent release of IL-6 and IL-8 was measured with ELISA. VEGF secretion from ARPE-19 cells was determined up to 24 h. Hypoxia induced significant (P < 0.01) increases in the levels of both IL-6 and IL-8 in ARPE-19 cells, and LPS pre-treatment further enhanced these responses. Hypoxia exposure did not affect the IL-1β or IL-18 release irrespective of LPS pre-treatment. If primary RPE cells were incubated for 4 h in hypoxic conditions, IL-6 and IL-8 concentrations were increased by 7 and 8-fold respectively. Hypoxia increased the VEGF secretion from ARPE-19 cells in a similar manner with or without pre-treatment with LPS. Hypoxia causes an inflammatory reaction in RPE cells that is potentiated by pre-treatment with the Toll-like receptor-activating agent, LPS. The secretion of VEGF from these cells is regulated directly by hypoxia and is not mediated by inflammation.

Non-viral vectors based on magnetoplexes, lipoplexes and polyplexes for VEGF gene delivery into central nervous system cells.

PubMed

Villate-Beitia, Ilia; Puras, Gustavo; Soto-Sánchez, Cristina; Agirre, Mireia; Ojeda, Edilberto; Zarate, Jon; Fernández, Eduardo; Pedraz, José Luis

2017-04-15

Nanotechnology based non-viral vectors hold great promise to deliver therapeutic genes into the central nervous system (CNS) in a safe and controlled way. Vascular endothelial growth factor (VEGF) is a potential therapeutic gene candidate for CNS disorders due to its specific roles in brain angiogenesis and neuroprotection. In this work, we elaborated three different non-viral vectors based on magnetic, cationic lipid and polymeric nanoparticles complexed to the phVEGF165aIRESGFP plasmid, which codifies the VEGF protein -extracellular- and the green fluorescent protein (GFP) -intracellular-. Nanoparticles and corresponding nanoplexes -magnetoplexes, lipoplexes and polyplexes- were characterized in terms of size, zeta potential, polydispersity index, morphology and ability to bind, release and protect DNA. Transfection efficiencies of nanoplexes were measured in terms of percentage of GFP expressing cells, mean fluorescent intensity (MFI) and VEGF (ng/ml) production in HEK293, C6 and primary neuronal culture cells. Magnetoplexes showed the highest transfection efficiencies in C6, followed by lipoplexes, and in primary neuronal culture cells, followed by polyplexes. Lipoplexes were the most efficient in HEK293 cells, followed by magnetoplexes. The biological activity of VEGF was confirmed by its proliferative effect in HUVEC cells. Overall, these results provide new insights for VEGF gene delivery into CNS cells using non-viral vectors. Copyright © 2017. Published by Elsevier B.V.

ERK1/2/COX-2/PGE2 signaling pathway mediates GPR91-dependent VEGF release in streptozotocin-induced diabetes

PubMed Central

Li, Tingting; Hu, Jianyan; Du, Shanshan; Chen, Yongdong; Wang, Shuai

2014-01-01

Purpose Retinal vascular dysfunction caused by vascular endothelial growth factor (VEGF) is the major pathological change that occurs in diabetic retinopathy (DR). It has recently been demonstrated that G protein-coupled receptor 91 (GPR91) plays a major role in both vasculature development and retinal angiogenesis. In this study, we examined the signaling pathways involved in GPR91-dependent VEGF release during the early stages of retinal vascular change in streptozotocin-induced diabetes. Methods Diabetic rats were assigned randomly to receive intravitreal injections of shRNA lentiviral particles targeting GPR91 (LV.shGPR91) or control particles (LV.shScrambled). Accumulation of succinate was assessed by gas chromatography-mass spectrometry (GC-MS). At 14 weeks, the ultrastructure and function of the retinal vessels of diabetic retinas with or without shRNA treatment were assessed using hematoxylin and eosin (HE) staining, transmission electron microscopy (TEM), and Evans blue dye permeability. The expression of GPR91, extracellular signal-regulated kinases 1 and 2 (ERK1/2) and cyclooxygenase-2 (COX-2) were measured using immunofluorescence and western blotting. COX-2 and VEGF mRNA were determined by quantitative RT–PCR. Prostaglandin E2 (PGE2) and VEGF secretion were detected using an enzyme-linked immunosorbent assay. Results Succinate exhibited abundant accumulation in diabetic rat retinas. The retinal telangiectatic vessels, basement membrane thickness, and Evans blue dye permeability were attenuated by treatment with GPR91 shRNA. In diabetic rats, knockdown of GPR91 inhibited the activities of ERK1/2 and COX-2 as well as the expression of PGE2 and VEGF. Meanwhile, COX-2, PGE2, and VEGF expression was inhibited by ERK1/2 inhibitor U0126 and COX-2 inhibitor NS-398. Conclusions Our data suggest that hyperglycemia causes succinate accumulation and GPR91 activity in retinal ganglion cells, which mediate VEGF-induced retinal vascular change via the ERK1/2/COX-2/PGE2 pathway. This study highlights the signaling pathway as a potential target for intervention in DR. PMID:25324681

The Novel Mechanisms Concerning the Inhibitions of Palmitate-Induced Proinflammatory Factor Releases and Endogenous Cellular Stress with Astaxanthin on MIN6 β-Cells.

PubMed

Kitahara, Atsuko; Takahashi, Kazuto; Morita, Naru; Murashima, Toshitaka; Onuma, Hirohisa; Sumitani, Yoshikazu; Tanaka, Toshiaki; Kondo, Takuma; Hosaka, Toshio; Ishida, Hitoshi

2017-06-20

Astaxanthin, an antioxidant agent, can protect pancreatic β-cells of db/db mice from glucotoxicity and resolve chronic inflammation in adipose tissue. Nonetheless, the effects of astaxanthin on free-fatty-acid-induced inflammation and cellular stress in β-cells remain to be demonstrated. Meanwhile, palmitate enhances the secretion of pro-inflammatory adipokines monocyte chemoattractant protein-1 (MCP-1) and VEGF 120 (vascular endothelial growth factor). We therefore investigated the influence of astaxanthin on palmitate-stimulated MCP-1 and VEGF 120 secretion in mouse insulinoma (MIN6) pancreatic β-cells. Furthermore, whether astaxanthin prevents cellular stress in MIN6 cells was also assessed. Pre-treatment with astaxanthin or with N -acetyl-cysteine (NAC) which is an antioxidant drug, significantly attenuated the palmitate-induced MCP-1 release through downregulation of phosphorylated c-Jun NH₂-terminal protein kinase (JNK) pathways, and suppressed VEGF 120 through the PI3K/Akt pathways relative to the cells stimulated with palmitate alone. In addition, palmitate significantly upregulated homologous protein (CHOP) and anti-glucose-regulated protein (GRP78), which are endoplasmic reticulum (ER) stress markers, in MIN6 cells. On the other hand, astaxanthin attenuated the increased CHOP content, but further up-regulated palmitate-stimulated GRP78 protein expression. By contrast, NAC had no effects on either CHOP or GRP78 enhancement induced by palmitate in MIN6 cells. In conclusion, astaxanthin diminishes the palmitate-stimulated increase in MCP-1 secretion via the downregulation of JNK pathways in MIN6 cells, and affects VEGF 120 secretion through PI3K/Akt pathways. Moreover, astaxanthin can prevent not only oxidative stress caused endogenously by palmitate but also ER stress, which NAC fails to attenuate, via upregulation of GRP78, an ER chaperon.

The Novel Mechanisms Concerning the Inhibitions of Palmitate-Induced Proinflammatory Factor Releases and Endogenous Cellular Stress with Astaxanthin on MIN6 β-Cells

PubMed Central

Kitahara, Atsuko; Takahashi, Kazuto; Morita, Naru; Murashima, Toshitaka; Onuma, Hirohisa; Sumitani, Yoshikazu; Tanaka, Toshiaki; Kondo, Takuma; Hosaka, Toshio; Ishida, Hitoshi

2017-01-01

Astaxanthin, an antioxidant agent, can protect pancreatic β-cells of db/db mice from glucotoxicity and resolve chronic inflammation in adipose tissue. Nonetheless, the effects of astaxanthin on free-fatty-acid-induced inflammation and cellular stress in β-cells remain to be demonstrated. Meanwhile, palmitate enhances the secretion of pro-inflammatory adipokines monocyte chemoattractant protein-1 (MCP-1) and vascular endothelial growth factor (VEGF120). We therefore investigated the influence of astaxanthin on palmitate-stimulated MCP-1 and VEGF120 secretion in mouse insulinoma (MIN6) pancreatic β-cells. Furthermore, whether astaxanthin prevents cellular stress in MIN6 cells was also assessed. Pre-treatment with astaxanthin or with N-acetyl-cysteine (NAC) which is an antioxidant drug, significantly attenuated the palmitate-induced MCP-1 release through downregulation of phosphorylated c-Jun NH2-terminal protein kinase (JNK) pathways, and suppressed VEGF120 through the PI3K/Akt pathways relative to the cells stimulated with palmitate alone. In addition, palmitate significantly upregulated homologous protein (CHOP) and anti-glucose-regulated protein (GRP78), which are endoplasmic reticulum (ER) stress markers, in MIN6 cells. On the other hand, astaxanthin attenuated the increased CHOP content, but further up-regulated palmitate-stimulated GRP78 protein expression. By contrast, NAC had no effects on either CHOP or GRP78 enhancement induced by palmitate in MIN6 cells. In conclusion, astaxanthin diminishes the palmitate-stimulated increase in MCP-1 secretion via the downregulation of JNK pathways in MIN6 cells, and affects VEGF120 secretion through PI3K/Akt pathways. Moreover, astaxanthin can prevent not only oxidative stress caused endogenously by palmitate but also ER stress, which NAC fails to attenuate, via upregulation of GRP78, an ER chaperon. PMID:28632169

Evaluation of an injectable polymeric delivery system for controlled and localized release of biological factors to promote therapeutic angiogenesis

NASA Astrophysics Data System (ADS)

Rocker, Adam John

Cardiovascular disease remains as the leading cause of death worldwide and is frequently associated with partial or full occlusion of coronary arteries. Currently, angioplasty and bypass surgery are the standard approaches for treating patients with these ischemic heart conditions. However, a large number of patients cannot undergo these procedures. Therapeutic angiogenesis provides a minimally invasive tool for treating cardiovascular diseases by inducing new blood vessel growth from the existing vasculature. Angiogenic growth factors can be delivered locally through gene, cell, and protein therapy. Natural and synthetic polymer growth factor delivery systems are under extensive investigation due their widespread applications and promising therapeutic potential. Although biocompatible, natural polymers often suffer from batch-to-batch variability which can cause unpredictable growth factor release rates. Synthetic polymers offer advantages for growth factor delivery as they can be easily modified to control release kinetics. During the angiogenesis process, vascular endothelial growth factor (VEGF) is necessary to initiate neovessel formation while platelet-derived growth factor (PDGF) is needed later to help stabilize and mature new vessels. In the setting of myocardial infarction, additional anti-inflammatory cytokines like IL-10 are needed to help optimize cardiac repair and limit the damaging effects of inflammation following infarction. To meet these angiogenic and anti-inflammatory needs, an injectable polymer delivery system created from a sulfonated reverse thermal gel encapsulating micelle nanoparticles was designed and evaluated. The sulfonate groups on the thermal gel electrostatically bind to VEGF which controls its release rate, while the micelles are loaded with PDGF and are slowly released as the gel degrades. IL-10 was loaded into the system as well and diffused from the gel over time. An in vitro release study was performed which demonstrated the sequential release capabilities of the polymer system. The ability of the polymer system to induce new blood vessel formation was analyzed in vivo using a subcutaneous injection mouse model. Histological assessment was used to quantify blood vessel formation and an inflammatory response which showed that the polymer delivery system demonstrated a significant increase in functional and mature vessel formation while significantly reducing inflammation.

Opiate receptor blockade on human granulosa cells inhibits VEGF release.

PubMed

Lunger, Fabian; Vehmas, Anni P; Fürnrohr, Barbara G; Sopper, Sieghart; Wildt, Ludwig; Seeber, Beata

2016-03-01

The objectives of this study were to determine whether the main opioid receptor (OPRM1) is present on human granulosa cells and if exogenous opiates and their antagonists can influence granulosa cell vascular endothelial growth factor (VEGF) production via OPRM1. Granulosa cells were isolated from women undergoing oocyte retrieval for IVF. Complementary to the primary cells, experiments were conducted using COV434, a well-characterized human granulosa cell line. Identification and localization of opiate receptor subtypes was carried out using Western blot and flow cytometry. The effect of opiate antagonist on granulosa cell VEGF secretion was assessed by enzyme-linked immunosorbent assay. For the first time, the presence of OPRM1 on human granulosa cells is reported. Blocking of opiate signalling using naloxone, a specific OPRM1 antagonist, significantly reduced granulosa cell-derived VEGF levels in both COV434 and granulosa-luteal cells (P < 0.01). The presence of opiate receptors and opiate signalling in granulosa cells suggest a possible role in VEGF production. Targeting this signalling pathway could prove promising as a new clinical option in the prevention and treatment of ovarian hyperstimulation syndrome. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Hypoxic stress, brain vascular system, and β-amyloid: a primary cell culture study.

PubMed

Muche, Abebe; Bürger, Susanne; Arendt, Thomas; Schliebs, Reinhard

2015-01-01

This study stresses the hypothesis whether hypoxic events contribute to formation and deposition of β-amyloid (Aβ) in cerebral blood vessels by affecting the processing of endothelial amyloid precursor protein (APP). Therefore, cerebral endothelial cells (ECs) derived from transgenic Tg2576 mouse brain, were subjected to short periods of hypoxic stress, followed by assessment of formation and secretion of APP cleavage products sAPPα, sAPPβ, and Aβ as well as the expression of endothelial APP. Hypoxic stress of EC leads to enhanced secretion of sAPPβ into the culture medium as compared to normoxic controls, which is accompanied by increased APP expression, induction of vascular endothelial growth factor (VEGF) synthesis, nitric oxide production, and differential changes in endothelial p42/44 (ERK1/2) expression. The hypoxia-mediated up-regulation of p42/44 at a particular time of incubation was accompanied by a corresponding down-regulation of the phosphorylated form of p42/44. To reveal any role of hypoxia-induced VEGF in endothelial APP processing, ECs were exposed by VEGF. VEGF hardly affected the amount of sAPPβ and Aβ(1-40) secreted into the culture medium, whereas the suppression of the VEGF receptor action by SU-5416 resulted in decreased release of sAPPβ and Aβ(1-40) in comparison to control incubations, suggesting a role of VEGF in controlling the activity of γ-secretase, presumably via the VEGF receptor-associated tyrosine kinase. The data suggest that hypoxic stress represents a mayor risk factor in causing Aβ deposition in the brain vascular system by favoring the amyloidogenic route of endothelial APP processing. The hypoxic-stress-induced changes in β-secretase activity are presumably mediated by altering the phosphorylation status of p42/44, whereas the stress-induced up-regulation of VEGF appears to play a counteracting role by maintaining the balance of physiological APP processing.

Divergent effects of new cyclooxygenase inhibitors on gastric ulcer healing: Shifting the angiogenic balance

PubMed Central

Ma, Li; del Soldato, Piero; Wallace, John L.

2002-01-01

Delayed gastric ulcer healing is a well recognized problem associated with the use of cyclooxygenase (COX) inhibitors. In contrast, NO-releasing COX inhibitors do not interfere with ulcer healing. These divergent effects may in part be due to differences in their effects on platelets, which are known to influence ulcer healing. Therefore, we compared the effects of a nonselective COX inhibitor (flurbiprofen), a nitric oxide-releasing COX inhibitor (HCT-1026), and a selective COX-2 inhibitor (celecoxib) on gastric ulcer healing, angiogenesis, and platelet/serum levels of vascular endothelial growth factor (VEGF) and endostatin. Gastric ulcers were induced in rats by serosal application of acetic acid. Daily treatment with the test drugs was started 3 days later and continued for 1 week. Celecoxib and flurbiprofen impaired angiogenesis and delayed ulcer healing, as well as increasing serum endostatin levels relative to those of VEGF. HCT-1026 did not delay ulcer healing nor impair angiogenesis, and also did not change the ratio of serum endostatin to VEGF. Incubation of human umbilical vein endothelial cells with serum from celecoxib- or flurbiprofen-treated rats resulted in suppressed proliferation and increased apoptosis, effects that were reversed by an antiendostatin antibody. These results demonstrate a previously unrecognized mechanism through which nonsteroidal antiinflammatory drugs can delay ulcer healing, namely, through altering the balance of anti- and proangiogenic factors in the serum. The absence of a delaying effect of HCT-1026 on ulcer healing may be related to the maintenance of a more favorable balance in serum levels of pro- and antiangiogenic growth factors. PMID:12232050

Endogenous Stem Cells Were Recruited by Defocused Low-Energy Shock Wave in Treating Diabetic Bladder Dysfunction.

PubMed

Jin, Yang; Xu, Lina; Zhao, Yong; Wang, Muwen; Jin, Xunbo; Zhang, Haiyang

2017-04-01

Defocused low-energy shock wave (DLSW) has been shown effects on activating mesenchymal stromal cells (MSCs) in vitro. In this study, recruitment of endogenous stem cells was firstly examined as an important pathway during the healing process of diabetic bladder dysfunction (DBD) treated by DLSW in vivo. Neonatal rats received intraperitoneal injection of 5-ethynyl-2-deoxyuridine (EdU) and then DBD rat model was created by injecting streptozotocin. Four weeks later, DLSW treatment was performed. Afterward, their tissues were examined by histology. Meanwhile, adipose tissue-derived stem cells (ADSCs) were treated by DLSW in vitro. Results showed DLSW ameliorated voiding function of diabetic rats by recruiting EdU + Stro-1 + CD34 - endogenous stem cells to release abundant nerve growth factor (NGF) and vascular endothelial growth factor (VEGF). Some EdU + cells overlapped with staining of smooth muscle actin. After DLSW treatment, ADSCs showed higher migration ability, higher expression level of stromal cell-derived factor-1 and secreted more NGF and VEGF. In conclusion, DLSW could ameliorate DBD by recruiting endogenous stem cells. Beneficial effects were mediated by secreting NGF and VEGF, resulting into improved innervation and vascularization in bladder.

Emodin-Loaded Magnesium Silicate Hollow Nanocarriers for Anti-Angiogenesis Treatment through Inhibiting VEGF

PubMed Central

Ren, Hua; Zhu, Chao; Li, Zhaohui; Yang, Wei; Song, E

2014-01-01

The applications of anti-VEGF (vascular endothelial growth factor) treatment in ophthalmic fields to inhibit angiogenesis have been widely documented in recent years. However, the hydrophobic nature of many agents makes its delivery difficult in practice. Therefore, the aim of the present study was to introduce a new kind of hydrophobic drug carrier by employing nanoparticles with a hollow structure inside. Followed by the synthesis and characterization of magnesium silicate hollow spheres, cytotoxicity was evaluated in retina capillary endothelial cells. The loading and releasing capacity were tested by employing emodin, and the effect on VEGF expression was performed at the gene and protein level. Finally, an investigation on angiogenesis was carried on fertilized chicken eggs. The results indicated that the magnesium silicate nanoparticles had low toxicity. Emodin–MgSiO3 can inhibit the expression of both VEGF gene and protein effectively. Angiogenesis of eggs was also reduced significantly. Based on the above results, we concluded that magnesium silicate hollow spheres were good candidates as drug carriers with enough safety. PMID:25250911

Examination of the foreign body response to biomaterials by nonlinear intravital microscopy.

PubMed

Dondossola, Eleonora; Holzapfel, Boris M; Alexander, Stephanie; Filippini, Stefano; Hutmacher, Dietmar W; Friedl, Peter

2016-01-01

Implanted biomaterials often fail because they elicit a foreign body response (FBR) and concomitant fibrotic encapsulation. To design clinically relevant interference approaches, it is crucial to first examine the FBR mechanisms. Here, we report the development and validation of infrared-excited nonlinear microscopy to resolve the three-dimensional (3D) organization and fate of 3D-electrospun scaffolds implanted deep into the skin of mice, and the following step-wise FBR process. We observed that immigrating myeloid cells (predominantly macrophages of the M1 type) engaged and became immobilized along the scaffold/tissue interface, before forming multinucleated giant cells. Both macrophages and giant cells locally produced vascular endothelial growth factor (VEGF), which initiated and maintained an immature neovessel network, followed by formation of a dense collagen capsule 2-4 weeks post-implantation. Elimination of the macrophage/giant-cell compartment by clodronate and/or neutralization of VEGF by VEGF Trap significantly diminished giant-cell accumulation, neovascularization and fibrosis. Our findings identify macrophages and giant cells as incendiaries of the fibrotic encapsulation of engrafted biomaterials via VEGF release and neovascularization, and therefore as targets for therapy.

Examination of the foreign body response to biomaterials by nonlinear intravital microscopy

PubMed Central

Dondossola, Eleonora; Holzapfel, Boris M.; Alexander, Stephanie; Filippini, Stefano; Hutmacher, Dietmar W.; Friedl, Peter

2017-01-01

Implanted biomaterials often fail because they elicit a foreign body response (FBR) and concomitant fibrotic encapsulation. To design clinically relevant interference approaches, it is crucial to first examine the FBR mechanisms. Here, we report the development and validation of infrared-excited nonlinear microscopy to resolve the three-dimensional (3D) organization and fate of 3D-electrospun scaffolds implanted deep into the skin of mice, and the following step-wise FBR process. We observed that immigrating myeloid cells (predominantly macrophages of the M1 type) engaged and became immobilized along the scaffold/tissue interface, before forming multinucleated giant cells. Both macrophages and giant cells locally produced vascular endothelial growth factor (VEGF), which initiated and maintained an immature neovessel network, followed by formation of a dense collagen capsule 2–4 weeks post-implantation. Elimination of the macrophage/giant-cell compartment by clodronate and/or neutralization of VEGF by VEGF Trap significantly diminished giant-cell accumulation, neovascularization and fibrosis. Our findings identify macrophages and giant cells as incendiaries of the fibrotic encapsulation of engrafted biomaterials via VEGF release and neovascularization, and therefore as targets for therapy. PMID:28979821

PSMA, EpCAM, VEGF and GRPR as imaging targets in locally recurrent prostate cancer after radiotherapy.

PubMed

Rybalov, Maxim; Ananias, Hildo J K; Hoving, Hilde D; van der Poel, Henk G; Rosati, Stefano; de Jong, Igle J

2014-04-10

In this retrospective pilot study, the expression of the prostate-specific membrane antigen (PSMA), the epithelial cell adhesion molecule (EpCAM), the vascular endothelial growth factor (VEGF) and the gastrin-releasing peptide receptor (GRPR) in locally recurrent prostate cancer after brachytherapy or external beam radiotherapy (EBRT) was investigated, and their adequacy for targeted imaging was analyzed. Prostate cancer specimens were collected of 17 patients who underwent salvage prostatectomy because of locally recurrent prostate cancer after brachytherapy or EBRT. Immunohistochemistry was performed. A pathologist scored the immunoreactivity in prostate cancer and stroma. Staining for PSMA was seen in 100% (17/17), EpCAM in 82.3% (14/17), VEGF in 82.3% (14/17) and GRPR in 100% (17/17) of prostate cancer specimens. Staining for PSMA, EpCAM and VEGF was seen in 0% (0/17) and for GRPR in 100% (17/17) of the specimens' stromal compartments. In 11.8% (2/17) of cases, the GRPR staining intensity of prostate cancer was higher than stroma, while in 88.2% (15/17), the staining was equal. Based on the absence of stromal staining, PSMA, EpCAM and VEGF show high tumor distinctiveness. Therefore, PSMA, EpCAM and VEGF can be used as targets for the bioimaging of recurrent prostate cancer after EBRT to exclude metastatic disease and/or to plan local salvage therapy.

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) expression in colorectal cancer.

PubMed

Nagano, Hideki; Goi, Takanori; Koneri, Kenji; Hirono, Yasuo; Katayama, Kanji; Yamaguchi, Akio

2007-12-01

Vascular endothelial growth factor (VEGF) is known as an important factor in the growth and metastasis of cancer cells. In 2001, a novel angiogenesis factor, endocrine gland-derived vascular endothelial growth factor (EG-VEGF), was cloned. In this study, we investigated the expression of EG-VEGF in colorectal cancer, the relationship between its expression and clinicopathological factors, and the in vitro activity of EG-VEGF transfectants. We determined expression levels of EG-VEGF in 113 advanced colorectal cancers resected in our hospital by quantitative PCR, and compared the expression levels and clinicopathological findings by multivariate analyses. The expression of EG-VEGF mRNA was positive in 31 cancers and negative in 82 cancers. We found that compared with the negative expression of the EG-VEGF gene, its positive expression was more frequently associated with hematogenous metastasis, and was associated with a poorer survival rate. In addition, EG-VEGF transfectants showed a higher degree of in vitro tubular formation than control cells. We speculate that, in colorectal cancers, the EG-VEGF gene functions as an important factor in angiogenesis in primary and metastatic lesions, and consider that it is useful as a novel prognostic factor. EG-VEGF molecule-targeted therapy has the potential for improving survival rates.

Granulocyte-Colony Stimulating Factor Receptor, Tissue Factor, and VEGF-R Bound VEGF in Human Breast Cancer In Loco.

PubMed

Wojtukiewicz, Marek Z; Sierko, Ewa; Skalij, Piotr; Kamińska, Magda; Zimnoch, Lech; Brekken, Ralf A; Thorpe, Philip E

2016-01-01

Doxorubicin and docetaxel-based chemotherapy regimens used in breast cancer patients are associated with high risk of febrile neutropenia (FN). Granulocyte colony-stimulating factors (G-CSF) are recommended for both treating and preventing chemotherapy-induced neutropenia. Increased thrombosis incidence in G-CSF treated patients was reported; however, the underlying mechanisms remain unclear. The principal activator of blood coagulation in cancer is tissue factor (TF). It additionally contributes to cancer progression and stimulates angiogenesis. The main proangiogenic factor is vascular endothelial growth factor (VEGF). The aim of the study was to evaluate granulocyte-colony stimulating factor receptor (G-CSFR), tissue factor (TF) expression and vascular endothelial growth factor receptor (VEGF-R) bound VEGF in human breast cancer in loco. G-CSFR, TF and VEGFR bound VEGF (VEGF: VEGFR) were assessed in 28 breast cancer tissue samples. Immunohistochemical (IHC) methodologies according to ABC technique and double staining IHC procedure were employed utilizing antibodies against G-CSFR, TF and VEGF associated with VEGFR (VEGF: VEGFR). Expression of G-CSFR was demonstrated in 20 breast cancer tissue specimens (71%). In 6 cases (21%) the expression was strong (IRS 9-12). Strong expression of TF was observed in all investigated cases (100%). Moreover, expression of VEGF: VEGFR was visualized in cancer cells (IRS 5-8). No presence of G-CSFR, TF or VEGF: VEGFR was detected on healthy breast cells. Double staining IHC studies revealed co-localization of G-CSFR and TF, G-CSFR and VEGF: VEGFR, as well as TF and VEGF: VEGFR on breast cancer cells and ECs. The results of the study indicate that GCSFR, TF and VEGF: VEGFR expression as well as their co-expression might influence breast cancer biology, and may increase thromboembolic adverse events incidence.

Insulin-like growth factor binding protein-3 induces angiogenesis through IGF-I- and SphK1-dependent mechanisms.

PubMed

Granata, R; Trovato, L; Lupia, E; Sala, G; Settanni, F; Camussi, G; Ghidoni, R; Ghigo, E

2007-04-01

Angiogenesis is critical for development and repair, and is a prominent feature of many pathological conditions. Based on evidence that insulin-like growth factor binding protein (IGFBP)-3 enhances cell motility and activates sphingosine kinase (SphK) in human endothelial cells, we have investigated whether IGFBP-3 plays a role in promoting angiogenesis. IGFBP-3 potently induced network formation by human endothelial cells on Matrigel. Moreover, it up-regulated proangiogenic genes, such as vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP)-2 and -9. IGFBP-3 even induced membrane-type 1 MMP (MT1-MMP), which regulates MMP-2 activation. Decreasing SphK1 expression by small interfering RNA (siRNA), blocked IGFBP-3-induced network formation and inhibited VEGF, MT1-MMP but not IGF-I up-regulation. IGF-I activated SphK, leading to sphingosine-1-phosphate (S1P) formation. The IGF-I effect on SphK activity was blocked by specific inhibitors of IGF-IR, PI3K/Akt and ERK1/2 phosphorylation. The disruption of IGF-I signaling prevented the IGFBP-3 effect on tube formation, SphK activity and VEGF release. Blocking ERK1/2 signaling caused the loss of SphK activation and VEGF and IGF-I up-regulation. Finally, IGFBP-3 dose-dependently stimulated neovessel formation into subcutaneous implants of Matrigel in vivo. Thus, IGFBP-3 positively regulates angiogenesis through involvement of IGF-IR signaling and subsequent SphK/S1P activation.

Angiogenesis in arthritis: role in disease pathogenesis and as a potential therapeutic target.

PubMed

Paleolog, E M; Miotla, J M

1998-01-01

Rheumatoid arthritis (RA) is a chronic destructive musculo-skeletal disorder, associated with thickening of the synovial membrane lining the joints, inflammation and hyperproliferation of synovial cells, as well as a pro-inflammatory cytokine cascade, leukocyte infiltration, and tissue damage and bone resorption. An early event in RA is an alteration in blood vessel density and prominent neovascularisation. The hyperplasia of the synovium necessitates a compensatory increase in the number of blood vessels to nourish and oxygenate the tissue. However, angiogenesis may not keep pace with synovial proliferation, leading to regions of hypoperfusion and hypoxia. VEGF, a potent endothelial cell mitogen, is expressed in RA synovium and elevated in the serum of RA patients. We have reported that dissociated RA synovial membrane cells spontaneously secrete VEGF, and that release of VEGF by these cells is upregulated by cytokines and hypoxia. In a murine model of RA, VEGF is released from synovial cells isolated from the knees of arthritic but not healthy mice, and the extent of VEGF production correlates with the severity of arthritis. VEGF thus appears to play a key role in mediating alterations in synovial vessel density in arthritis. As a consequence, RA may be a potential target for anti-angiogenic therapy, and targeting VEGF may prove to be especially beneficial.

Dual effects of VEGF-B on activating cardiomyocytes and cardiac stem cells to protect the heart against short- and long-term ischemia-reperfusion injury.

PubMed

Li, Guo-Hua; Luo, Bin; Lv, Yan-Xia; Zheng, Fei; Wang, Lu; Wei, Meng-Xi; Li, Xian-Yu; Zhang, Lei; Wang, Jia-Ning; Chen, Shi-You; Tang, Jun-Ming; He, Xiaohua

2016-05-04

To investigate whether vascular endothelial growth factor B (VEGF-B) improves myocardial survival and cardiac stem cell (CSC) function in the ischemia-reperfusion (I/R) heart and promotes CSC mobilization and angiogenesis. One hour after myocardial ischemia and infarction, rats were treated with recombinant human VEGF-B protein following 24 h or 7 days of myocardial reperfusion. Twenty-four hours after myocardial I/R, VEGF-B increased pAkt and Bcl-2 levels, reduced p-p38MAPK, LC3-II/I, beclin-1, CK, CK-MB and cTnt levels, triggered cardiomyocyte protection against I/R-induced autophagy and apoptosis, and contributed to the decrease of infarction size and the improvement of heart function during I/R. Simultaneously, an in vitro hypoxia-reoxygenation (H/R)-induced H9c2 cardiomyocyte injury model was used to mimic I/R injury model in vivo; in this model, VEGF-B decreased LDH release, blocked H/R-induced apoptosis by inhibiting cell autophagy, and these special effects could be abolished by the autophagy inducer, rapamycin. Mechanistically, VEGF-B markedly activated the Akt signaling pathway while slightly inhibiting p38MAPK, leading to the blockade of cell autophagy and thus protecting cardiomyocyte from H/R-induced activation of the intrinsic apoptotic pathway. Seven days after I/R, VEGF-B induced the expression of SDF-1α and HGF, resulting in the massive mobilization and homing of c-Kit positive cells, triggering further angiogenesis and vasculogenesis in the infracted heart and contributing to the improvement of I/R heart function. VEGF-B could contribute to a favorable short- and long-term prognosis for I/R via the dual manipulation of cardiomyocytes and CSCs.

Nitric oxide synthesis leads to vascular endothelial growth factor synthesis via the NO/cyclic guanosine 3',5'-monophosphate (cGMP) pathway in human corpus cavernosal smooth muscle cells.

PubMed

Komori, Kazuhiko; Tsujimura, Akira; Takao, Tetsuya; Matsuoka, Yasuhiro; Miyagawa, Yasushi; Takada, Shingo; Nonomura, Norio; Okuyama, Akihiko

2008-07-01

Vascular smooth muscle cells express endothelial nitric oxide synthase (eNOS) and produce nitric oxide (NO). Recently, increased NO production has been reported to induce the synthesis and secretion of vascular endothelial growth factor (VEGF) via the NO/cyclic guanosine 3',5'-monophosphate (cGMP) pathway. L-arginine (L-arg), the precursor of NO, and selective phosphodiesterase type 5 (PDE-5) inhibitors that increase levels of intracellular cGMP may complementarily enhance VEGF synthesis in corpus cavernosal smooth muscle cells (CCSMCs), and may consequently restore impaired endothelial function. Expression of eNOS in corpus cavernosal smooth muscle has also been reported. However, it is unclear whether CCSMCs can generate NO. To elucidate whether CCSMCs can synthesize NO and whether NO synthesis enhances VEGF synthesis via the NO/cGMP pathway. Corpus cavernosal cells were cultured and characterized by immunocytochemistry and immunoblotting. CCSMCs were treated with L-arg. CCSMCs were also incubated with L-arg and with vardenafil, an inhibitor of PDE-5. Release of NO from cells was confirmed by assay of NO metabolites (NOx). Intracellular cGMP concentration and VEGF concentration in the medium were measured. Isolated cells were determined to be CCSMCs. The expression of eNOS by CCSMCs was also identified. NOx and cGMP levels in the L-arg-treated group were significantly greater than those in the control group. VEGF and cGMP levels in the L-arg-treated group were also significantly greater than those in the control group. VEGF and cGMP levels in the L-arg + vardenafil-treated group were significantly greater than those in the L-arg-treated group and the control group. CCSMCs express eNOS and synthesize NO. NO synthesis leads to enhancement of VEGF synthesis via the NO/cGMP pathway. Combined L-arg and vardenafil treatment, which can enhance VEGF production, may provide a novel therapeutic strategy for the treatment of erectile dysfunction as well as endothelial dysfunction in general.

Paracrine control of vascularization and neurogenesis by neurotrophins.

PubMed

Emanueli, Costanza; Schratzberger, Peter; Kirchmair, Rudolf; Madeddu, Paolo

2003-10-01

The neuronal system plays a fundamental role in the maturation of primitive embryonic vascular network by providing a paracrine template for blood vessel branching and arterial differentiation. Furthermore, postnatal vascular and neural regeneration cooperate in the healing of damaged tissue. Neurogenesis continues in adulthood although confined to specific brain regions. Following ischaemic insult, neural staminal cells contribute towards the healing process through the stimulation of neurogenesis and vasculogenesis. Evidence indicates that nerves and blood vessels exert a reciprocal control of their own growth by paracrine mechanisms. For instance, guidance factors, including vascular endothelial growth factor A (VEGF-A) and semaphorins, which share the ability of binding neuropilin receptors, play a pivotal role in the tridimensional growth pattern of arterial vessels and nerves. Animal models and clinical studies have demonstrated a role of VEGF-A in the pathogenesis of ischaemic and diabetic neuropathies. Further, supplementation with VEGF-A ameliorates neuronal recovery by exerting protective effects on nerves and stimulating reparative neovascularization. Human tissue kallikrein, a recently discovered angiogenic and arteriogenic factor, accelerates neuronal recovery by stimulating the growth of vasa nervorum. Conversely, the neurotrophin nerve growth factor, known to regulate neuronal survival and differentiation, is now regarded as a stimulator of angiogenesis and arteriogenesis. These results indicate that angiogenesis and neurogenesis are paracrinally regulated by growth factors released by endothelial cells and neurons. Supplementation of these growth factors, alone or in combination, could benefit the treatment of ischaemic diseases and neuropathies.

S100 chemokines mediate bookmarking of premetastatic niches

PubMed Central

Rafii, Shahin; Lyden, David

2010-01-01

Primary tumours release soluble factors, including VEGF-A, TGFβ and TNFα, which induce expression of the chemokines S100A8 and S100A9 in the myeloid and endothelial cells within the lung before tumour metastasis. These chemokine-activated premetastatic niches support adhesion and invasion of disseminating malignant cells, thereby establishing a fertile habitat for metastatic tumours. PMID:17139281

Activated PAR-2 regulates pancreatic cancer progression through ILK/HIF-α-induced TGF-α expression and MEK/VEGF-A-mediated angiogenesis.

PubMed

Chang, Li-Hsun; Pan, Shiow-Lin; Lai, Chin-Yu; Tsai, An-Chi; Teng, Che-Ming

2013-08-01

Tissue factor initiates the process of thrombosis and activates cell signaling through protease-activated receptor-2 (PAR-2). The aim of this study was to investigate the pathological role of PAR-2 signaling in pancreatic cancer. We first demonstrated that activated PAR-2 up-regulated the protein expression of both hypoxia-inducible factor-1α (HIF-1α) and HIF-2α, resulting in enhanced transcription of transforming growth factor-α (TGF-α). Down-regulation of HIFs-α by siRNA or YC-1, an HIF inhibitor, resulted in depleted levels of TGF-α protein. Furthermore, PAR-2, through integrin-linked kinase (ILK) signaling, including the p-AKT, promoted HIF protein expression. Diminishing ILK by siRNA decreased the levels of PAR-2-induced p-AKT, HIFs-α, and TGF-α; our results suggest that ILK is involved in the PAR-2-mediated TGF-α via an HIF-α-dependent pathway. Furthermore, the culture medium from PAR-2-treated pancreatic cancer cells enhanced human umbilical vein endothelial cell proliferation and tube formation, which was blocked by the MEK inhibitor, PD98059. We also found that activated PAR-2 enhanced tumor angiogenesis through the release of vascular endothelial growth factor-A (VEGF-A) from cancer cells, independent of the ILK/HIFs-α pathways. Consistent with microarray analysis, activated PAR-2 induced TGF-A and VEGF-A gene expression. In conclusion, the activation of PAR-2 signaling induced human pancreatic cancer progression through the induction of TGF-α expression by ILK/HIFs-α, as well as through MEK/VEGF-A-mediated angiogenesis, and it plays a role in the interaction between cancer progression and cancer-related thrombosis. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Tissue Factor-Factor VIIa Complex Triggers Protease Activated Receptor 2-Dependent Growth Factor Release and Migration in Ovarian Cancer

PubMed Central

Chanakira, Alice; Westmark, Pamela R.; Ong, Irene M.; Sheehan, John P.

2017-01-01

Objective Enhanced tissue factor (TF) expression in epithelial ovarian cancer (EOC) is associated with aggressive disease. Our objective was to evaluate the role of the TF-factor VIIa-protease-activated receptor-2 (PAR-2) pathway in human EOC. Methods TCGA RNAseq data from EOC databases were analyzed for PAR expression. Cell and microparticle (MP) associated TF protein expression (Western blot) and MP-associated coagulant activity were determined in human EOC (SKOV-3, OVCAR-3 and CaOV-3) and control cell lines. PAR-1 and PAR-2 protein expression were similarly examined. The PAR dependence of VEGF-A release (ELISA) and chemotactic migration in response to FVIIa and cellular proliferation in response to thrombin was evaluated with small molecule antagonists. Results Relative mRNA expression consistently demonstrated PAR-2>PAR-1≫PAR-3/4 in multiple EOC datasets. Human EOC cell line lysates confirmed expression of TF, PAR-1 and PAR-2 proteins. MPs isolated from EOC cell lines demonstrated markedly enhanced (4–10 fold) TF coagulant activity relative to control cell lines. FVIIa induced a dose-dependent increase in VEGF-A release (2.5-3 fold) from EOC cell lines that was abrogated by the PAR-2 antagonist ENMD-1068. FVIIa treatment of CaOV-3 and OVCAR-3 cells resulted in increased chemotactic migration that was abolished by ENMD-1068. Thrombin induced dose-dependent EOC cell line proliferation was completely reversed by the PAR-1 antagonist vorapaxar. Small molecule antagonists had no effect on these phenotypes without protease present. Conclusions Enhanced activity of the TF-FVIIa-PAR-2 axis may contribute to the EOC progression via PAR-2 dependent signaling that supports an angiogenic and invasive phenotype and local thrombin generation supporting PAR-1 dependent proliferation. PMID:28148395

Effects of EG-VEGF, VEGF and TGF-β1 on pregnancy outcome in patients undergoing IVF-ET treatment.

PubMed

Gao, Min-zhi; Zhao, Xiao-ming; Lin, Yi; Sun, Zhao-gui; Zhang, Hui-qin

2012-10-01

To investigate the correlation of endocrine gland-derived vascular endothelial growth factor (EG-VEGF), vascular endothelial growth factor (VEGF) and transforming growth factor beta 1 (TGF-β1) with the corresponding reproductive outcome in patients who received in vitro fertilization-embryo transfer (IVF-ET). Sixty-seven women undergoing IVF-ET at a university tertiary hospital were recruited for a prospective study. Concentrations of EG-VEGF, VEGF and TGF-β1 were measured by enzyme-linked immunosorbent assay (ELISA) in follicular fluid (FF) collected during oocyte retrieval (OR) and in serum collected 2 days after OR. In FF, concentrations of both EG-VEGF and VEGF were negatively correlated with peak E2 and the number of MII oocytes retrieved, and positively correlated with each other. In serum, concentrations of all the three growth factors were positively correlated with the rate of good quality embryo, and with one another. Patients in the pregnancy group had lower peak E2 concentrations and higher serum EG-VEGF concentrations than those in the non-pregnancy group, but such tendency was not observed in the case of VEGF and TGF-β1. Both concentrations of EG-VEGF and VEGF in FF were negatively correlated with ovarian response and oocyte maturation. Concentrations of all the three growth factors in serum were positively correlated with embryo quality, but only serum concentrations of EG-VEGF were associated with the pregnancy outcome.

Delayed brain radiation necrosis: pathological review and new molecular targets for treatment.

PubMed

Furuse, Motomasa; Nonoguchi, Naosuke; Kawabata, Shinji; Miyatake, Shin-Ichi; Kuroiwa, Toshihiko

2015-12-01

Delayed radiation necrosis is a well-known adverse event following radiotherapy for brain diseases and has been studied since the 1930s. The primary pathogenesis is thought to be the direct damage to endothelial and glial cells, particularly oligodendrocytes, which causes vascular hyalinization and demyelination. This primary pathology leads to tissue inflammation and ischemia, inducing various tissue protective responses including angiogenesis. Macrophages and lymphocytes then infiltrate the surrounding areas of necrosis, releasing inflammatory cytokines such as interleukin (IL)-1α, IL-6, and tumor necrosis factor (TNF)-α. Microglia also express these inflammatory cytokines. Reactive astrocytes play an important role in angiogenesis, expressing vascular endothelial growth factor (VEGF). Some chemokine networks, like the CXCL12/CXCR4 axis, are upregulated by tissue inflammation. Hypoxia may mediate the cell-cell interactions among reactive astrocytes, macrophages, and microglial cells around the necrotic core. Recently, bevacizumab, an anti-VEGF antibody, has demonstrated promising results as an alternative treatment for radiation necrosis. The importance of VEGF in the pathophysiology of brain radiation necrosis is being recognized. The discovery of new molecular targets could facilitate novel treatments for radiation necrosis. This literature review will focus on recent work characterizing delayed radiation necrosis in the brain.

Cholangiocytes and blood supply.

PubMed

Gaudio, Eugenio; Franchitto, Antonio; Pannarale, Luigi; Carpino, Guido; Alpini, Gianfranco; Francis, Heather; Glaser, Shannon; Alvaro, Domenico; Onori, Paolo

2006-06-14

The microvascular supply of the biliary tree, the peribiliary plexus (PBP), stems from the hepatic artery branches and flows into the hepatic sinusoids. A detailed three-dimensional study of the PBP has been performed by using the Scanning Electron Microscopy vascular corrosion casts (SEMvcc) technique. Considering that the PBP plays a fundamental role in supporting the secretory and absorptive functions of the biliary epithelium, their organization in either normalcy and pathology is explored. The normal liver shows the PBP arranged around extra- and intrahepatic biliary tree. In the small portal tract PBP was characterized by a single layer of capillaries which progressively continued with the extrahepatic PBP where it showed a more complex vascular network. After common duct ligation (BDL), progressive modifications of bile duct and PBP proliferation are observed. The PBP presents a three-dimensional network arranged around many bile ducts and appears as bundles of vessels, composed by capillaries of homogeneous diameter with a typical round mesh structure. The PBP network is easily distinguishable from the sinusoidal network which appears normal. Considering the enormous extension of the PBP during BDL, the possible role played by the Vascular Endothelial Growth Factor (VEGF) is evaluated. VEGF-A, VEGF-C and their related receptors appeared highly immunopositive in proliferating cholangiocytes of BDL rats. The administration of anti-VEGF-A or anti-VEGF-C antibodies to BDL rats as well as hepatic artery ligation induced a reduced bile duct mass. The administration of rVEGF-A to BDL hepatic artery ligated rats prevented the decrease of cholangiocyte proliferation and VEGF-A expression as compared to BDL control rats. These data suggest the role of arterial blood supply of the biliary tree in conditions of cholangiocyte proliferation, such as it occurs during chronic cholestasis. On the other hand, the role played by VEGF as a tool of cross-talk between cholangiocytes and PBP endothelial cells suggests that manipulation of VEGF release and function could represent a therapeutic strategy for human pathological conditions characterized by damage of hepatic artery or the biliary tree.

Vascular endothelial growth factor (VEGF) inhibition--a critical review.

PubMed

Moreira, Irina Sousa; Fernandes, Pedro Alexandrino; Ramos, Maria João

2007-03-01

Angiogenesis, or formation of new blood capillaries from preexisting vessels, plays both beneficial and damaging roles in the organism. It is a result of a complex balance of positive and negative regulators, and vascular endothelial growth factor (VEGF) is one of the most important pro-angiogenic factors involved in tumor angiogenesis. VEGF increases vascular permeability, which might facilitate tumor dissemination via the circulation causing a greater delivery of oxygen and nutrients; it recruits circulating endothelial precursor cells, and acts as a survival factor for immature tumor blood vessels. The endotheliotropic activities of VEGF are mediated through the VEGF-specific tyrosine-kinase receptors: VEGFR-1, VEGFR-2 and VEGFR-3. VEGF and its receptors play a central role in tumor angiogenesis, and therefore the blockade of this pathway is a promising therapeutic strategy for inhibiting angiogenesis and tumor growth. A number of different strategies to inhibit VEGF signal transduction are in development and they include the development of humanized neutralizing anti-VEGF monoclonal antibodies, receptor antagonists, soluble receptors, antagonistic VEGF mutants, and inhibitors of VEGF receptor function. These agents can be divided in two broad classes, namely agents designed to target the VEGF activity and agents designed to target the surface receptor function. The main purpose of this review is to summarize all the available information regarding the importance of the pro-angiogenic factor VEGF in cancer therapy. After an overview of the VEGF family and their respective receptors, we shall focus our attention on the different VEGF-inhibitors existent nowadays. Agents based upon anti-VEGF therapy have provided solid proofs about their success, and therefore we believe that a critical review is of the utmost importance to help researchers in their future work.

Survivin expression promotes VEGF-induced tumor angiogenesis via PI3K/Akt enhanced β-catenin/Tcf-Lef dependent transcription.

PubMed

Fernández, Jaime G; Rodríguez, Diego A; Valenzuela, Manuel; Calderon, Claudia; Urzúa, Ulises; Munroe, David; Rosas, Carlos; Lemus, David; Díaz, Natalia; Wright, Mathew C; Leyton, Lisette; Tapia, Julio C; Quest, Andrew Fg

2014-09-09

Early in cancer development, tumour cells express vascular endothelial growth factor (VEGF), a secreted molecule that is important in all stages of angiogenesis, an essential process that provides nutrients and oxygen to the nascent tumor and thereby enhances tumor-cell survival and facilitates growth. Survivin, another protein involved in angiogenesis, is strongly expressed in most human cancers, where it promotes tumor survival by reducing apoptosis as well as favoring endothelial cell proliferation and migration. The mechanisms by which cancer cells induce VEGF expression and angiogenesis upon survivin up-regulation remain to be fully established. Since the PI3K/Akt signalling and β-catenin-Tcf/Lef dependent transcription have been implicated in the expression of many cancer-related genes, including survivin and VEGF, we evaluated whether survivin may favor VEGF expression, release from tumor cells and induction of angiogenesis in a PI3K/Akt-β-catenin-Tcf/Lef-dependent manner. Here, we provide evidence linking survivin expression in tumor cells to increased β-catenin protein levels, β-catenin-Tcf/Lef transcriptional activity and expression of several target genes of this pathway, including survivin and VEGF, which accumulates in the culture medium. Alternatively, survivin downregulation reduced β-catenin protein levels and β-catenin-Tcf/Lef transcriptional activity. Also, using inhibitors of PI3K and the expression of dominant negative Akt, we show that survivin acts upstream in an amplification loop to promote VEGF expression. Moreover, survivin knock-down in B16F10 murine melanoma cells diminished the number of blood vessels and reduced VEGF expression in tumors formed in C57BL/6 mice. Finally, in the chick chorioallantoid membrane assay, survivin expression in tumor cells enhanced VEGF liberation and blood vessel formation. Importantly, the presence of neutralizing anti-VEGF antibodies precluded survivin-enhanced angiogenesis in this assay. These findings provide evidence for the existance of a posititve feedback loop connecting survivin expression in tumor cells to PI3K/Akt enhanced β-catenin-Tcf/Lef-dependent transcription followed by secretion of VEGF and angiogenesis.

DNA containing CpG motifs induces angiogenesis

NASA Astrophysics Data System (ADS)

Zheng, Mei; Klinman, Dennis M.; Gierynska, Malgorzata; Rouse, Barry T.

2002-06-01

New blood vessel formation in the cornea is an essential step in the pathogenesis of a blinding immunoinflammatory reaction caused by ocular infection with herpes simplex virus (HSV). By using a murine corneal micropocket assay, we found that HSV DNA (which contains a significant excess of potentially bioactive "CpG" motifs when compared with mammalian DNA) induces angiogenesis. Moreover, synthetic oligodeoxynucleotides containing CpG motifs attract inflammatory cells and stimulate the release of vascular endothelial growth factor (VEGF), which in turn triggers new blood vessel formation. In vitro, CpG DNA induces the J774A.1 murine macrophage cell line to produce VEGF. In vivo CpG-induced angiogenesis was blocked by the administration of anti-mVEGF Ab or the inclusion of "neutralizing" oligodeoxynucleotides that specifically oppose the stimulatory activity of CpG DNA. These findings establish that DNA containing bioactive CpG motifs induces angiogenesis, and suggest that CpG motifs in HSV DNA may contribute to the blinding lesions of stromal keratitis.

Nanotechnology-based drug delivery treatments and specific targeting therapy for age-related macular degeneration.

PubMed

Lin, Tai-Chi; Hung, Kuo-Hsuan; Peng, Chi-Hsien; Liu, Jorn-Hon; Woung, Lin-Chung; Tsai, Ching-Yao; Chen, Shih-Jen; Chen, Yan-Ting; Hsu, Chih-Chien

2015-11-01

Nanoparticles combined with cells, drugs, and specially designed genes provide improved therapeutic efficacy in studies and clinical setting, demonstrating a new era of treatment strategy, especially in retinal diseases. Nanotechnology-based drugs can provide an essential platform for sustaining, releasing and a specific targeting design to treat retinal diseases. Poly-lactic-co-glycolic acid is the most widely used biocompatible and biodegradable polymer approved by the Food and Drug Administration. Many studies have attempted to develop special devices for delivering small-molecule drugs, proteins, and other macromolecules consistently and slowly. In this article, we first review current progress in the treatment of age-related macular degeneration. Then, we discuss the function of vascular endothelial growth factor (VEGF) and the pharmacological effects of anti-VEGF-A antibodies and soluble or modified VEGF receptors. Lastly, we summarize the combination of antiangiogenic therapy and nanomedicines, and review current potential targeting therapy in age-related macular degeneration. Copyright © 2015. Published by Elsevier Taiwan.

ROS-induced ROS release orchestrated by Nox4, Nox2, and mitochondria in VEGF signaling and angiogenesis.

PubMed

Kim, Young-Mee; Kim, Seok-Jo; Tatsunami, Ryosuke; Yamamura, Hisao; Fukai, Tohru; Ushio-Fukai, Masuko

2017-06-01

Reactive oxygen species (ROS) derived from NADPH oxidase (NOX) and mitochondria play a critical role in growth factor-induced switch from a quiescent to an angiogenic phenotype in endothelial cells (ECs). However, how highly diffusible ROS produced from different sources can coordinate to stimulate VEGF signaling and drive the angiogenic process remains unknown. Using the cytosol- and mitochondria-targeted redox-sensitive RoGFP biosensors with real-time imaging, here we show that VEGF stimulation in human ECs rapidly increases cytosolic RoGFP oxidation within 1 min, followed by mitochondrial RoGFP oxidation within 5 min, which continues at least for 60 min. Silencing of Nox4 or Nox2 or overexpression of mitochondria-targeted catalase significantly inhibits VEGF-induced tyrosine phosphorylation of VEGF receptor type 2 (VEGFR2-pY), EC migration and proliferation at the similar extent. Exogenous hydrogen peroxide (H 2 O 2 ) or overexpression of Nox4, which produces H 2 O 2 , increases mitochondrial ROS (mtROS), which is prevented by Nox2 siRNA, suggesting that Nox2 senses Nox4-derived H 2 O 2 to promote mtROS production. Mechanistically, H 2 O 2 increases S36 phosphorylation of p66Shc, a key mtROS regulator, which is inhibited by siNox2, but not by siNox4. Moreover, Nox2 or Nox4 knockdown or overexpression of S36 phosphorylation-defective mutant p66Shc(S36A) inhibits VEGF-induced mtROS, VEGFR2-pY, EC migration, and proliferation. In summary, Nox4-derived H 2 O 2 in part activates Nox2 to increase mtROS via pSer36-p66Shc, thereby enhancing VEGFR2 signaling and angiogenesis in ECs. This may represent a novel feed-forward mechanism of ROS-induced ROS release orchestrated by the Nox4/Nox2/pSer36-p66Shc/mtROS axis, which drives sustained activation of angiogenesis signaling program. Copyright © 2017 the American Physiological Society.

Leukocyte- and platelet-rich fibrin (L-PRF) for long-term delivery of growth factor in rotator cuff repair: review, preliminary results and future directions.

PubMed

Zumstein, Matthias A; Berger, Simon; Schober, Martin; Boileau, Pascal; Nyffeler, Richard W; Horn, Michael; Dahinden, Clemens A

2012-06-01

Surgical repair of the rotator cuff repair is one of the most common procedures in orthopedic surgery. Despite it being the focus of much research, the physiological tendon-bone insertion is not recreated following repair and there is an anatomic non-healing rate of up to 94%. During the healing phase, several growth factors are upregulated that induce cellular proliferation and matrix deposition. Subsequently, this provisional matrix is replaced by the definitive matrix. Leukocyte- and platelet-rich fibrin (L-PRF) contain growth factors and has a stable dense fibrin matrix. Therefore, use of LPRF in rotator cuff repair is theoretically attractive. The aim of the present study was to determine 1) the optimal protocol to achieve the highest leukocyte content; 2) whether L-PRF releases growth factors in a sustained manner over 28 days; 3) whether standard/gelatinous or dry/compressed matrix preparation methods result in higher growth factor concentrations. 1) The standard L-PRF centrifugation protocol with 400 x g showed the highest concentration of platelets and leukocytes. 2) The L-PRF clots cultured in medium showed a continuous slow release with an increase in the absolute release of growth factors TGF-β1, VEGF and MPO in the first 7 days, and for IGF1, PDGF-AB and platelet activity (PF4=CXCL4) in the first 8 hours, followed by a decrease to close to zero at 28 days. Significantly higher levels of growth factor were expressed relative to the control values of normal blood at each culture time point. 3) Except for MPO and the TGFβ-1, there was always a tendency towards higher release of growth factors (i.e., CXCL4, IGF-1, PDGF-AB, and VEGF) in the standard/gelatinous- compared to the dry/compressed group. L-PRF in its optimal standard/gelatinous-type matrix can store and deliver locally specific healing growth factors for up to 28 days and may be a useful adjunct in rotator cuff repair.

Vascular endothelial growth factor from Trimeresurus jerdonii venom specifically binds to VEGFR-2.

PubMed

Zhong, Shurong; Wu, Jianbo; Cui, Yunpeng; Li, Rui; Zhu, Shaowen; Rong, Mingqiang; Lu, Qiumin; Lai, Ren

2015-09-01

Vascular endothelial growth factors (VEGFs) play important roles in angiogenesis. In this study, a vascular endothelial growth factor named TjsvVEGF was purified from the venom of Trimeresurus jerdonii by gel filtration, affinity, ion-exchange and high-performance liquid chromatography. TjsvVEGF was a homodimer with an apparent molecular mass of 29 kDa. The cDNA encoding TjsvVEGF was obtained by PCR. The open reading frame of the cloned TjsvVEGF was composed of 432 bp coding for a signal peptide of 24 amino acid residues and a mature protein of 119 amino acid residues. Compared with other snake venom VEGFs, the nucleotide and deduced protein sequences of the cloned TjsvVEGF were conserved. TjsvVEGF showed low heparin binding activity and strong capillary permeability increasing activity. The KD of TjsvVEGF to VEFGR-2 is 413 pM. However, the binding of TjsvVEGF to VEGFR-1 is too weak to detect. Though TjsvVEGF had high sequence identities (about 90%) with Crotalinae VEGFs, the receptor preference of TjsvVEGF was similar to Viperinae VEGFs which had lower sequence identities (about 60%) with it. TjsvVEGF might serve as a useful tool for the study of structure-function relationships of VEGFs and their receptors. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Protective role of vitamin E preconditioning of human dermal fibroblasts against thermal stress in vitro.

PubMed

Butt, Hira; Mehmood, Azra; Ali, Muhammad; Tasneem, Saba; Anjum, Muhammad Sohail; Tarar, Moazzam N; Khan, Shaheen N; Riazuddin, Sheikh

2017-09-01

Oxidative microenvironment of burnt skin restricts the outcome of cell based therapies of thermal skin injuries. The aim of this study was to precondition human dermal fibroblasts with an antioxidant such as vitamin E to improve their survival and therapeutic abilities in heat induced oxidative in vitro environment. Fibroblasts were treated with 100μM vitamin E for 24h at 37°C followed by heat shock for 10min at 51°C in fresh serum free medium. Preconditioning with vitamin E reduced cell injury as demonstrated by decreased expression of annexin-V, cytochrome p450 (CYP450) mediated oxidative reactions, senescence and release of lactate dehydrogenase (LDH) accomplished by down-regulated expression of pro-apoptotic BAX gene. Vitamin E preconditioned cells exhibited remarkable improvement in cell viability, release of paracrine factors such as epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), stromal derived factor-1alpha (SDF-1α) and also showed significantly up-regulated levels of PCNA, VEGF, BCL-XL, FGF7, FGF23, FLNβ and Col7α genes presumably through activation of phosphatidylinositol 3-kinase (PI3-K)/Akt pathway. The results suggest that pretreatment of fibroblasts with vitamin E prior to transplantation in burnt skin speeds up the wound healing process by improving the antioxidant scavenging responses in oxidative environment of transplanted burn wounds. Copyright © 2017 Elsevier Inc. All rights reserved.

Tissue factor-dependent vascular endothelial growth factor production by human fibroblasts in response to activated factor VII.

PubMed

Ollivier, V; Bentolila, S; Chabbat, J; Hakim, J; de Prost, D

1998-04-15

The transmembrane protein tissue factor (TF) is the cell surface receptor for coagulation factor VII (FVII) and activated factor VII (FVIIa). Recently, TF has been identified as a regulator of angiogenesis, tumor growth, and metastasis. This study was designed to link the binding of FVII(a) to its receptor, TF, with the subsequent triggering of angiogenesis through vascular endothelial growth factor (VEGF) production by human lung fibroblasts. We report that incubation of fibroblasts, which express constitutive surface TF, with FVII(a) induces VEGF synthesis. FVII(a)-induced VEGF secretion, assessed by a specific enzyme-linked immunosorbent assay, was time- and concentration-dependent. VEGF secretion was maximal after 24 hours of incubation of the cells with 100 nmol/L FVII(a) and represented a threefold induction of the basal VEGF level. Reverse transcriptase-polymerase chain reaction analysis of VEGF detected three mRNA species of 180, 312, and 384 bp corresponding, respectively, to VEGF121, VEGF165, and VEGF189. A 2.5- to 3.5-fold increase was observed for the 180- and 312-bp transcripts at 12 and 24 hours, respectively. FVII(a)-dependent VEGF production was inhibited by a pool of antibodies against TF, pointing to the involvement of this receptor. On specific active-site inhibition with dansyl-glutamyl-glycinyl-arginyl chloromethyl ketone, FVIIa lost 70% of its capacity to elicit VEGF production. Consistent with this, the native form (zymogen) of FVII only had a 1.8-fold stimulating effect. Protein tyrosine kinase and protein kinase C are involved in signal transduction leading to VEGF production, as shown by the inhibitory effects of genistein and GF 109203X. The results of this study indicate that TF is essential for VIIa-induced VEGF production by human fibroblasts and that its role is mainly linked to the proteolytic activity of the TF-VIIa complex.

Release of growth factors and the effect of age, sex, and severity of injury after long bone fracture. A preliminary report.

PubMed

Pountos, Ippokratis; Georgouli, Theodora; Henshaw, Karen; Bird, Howard; Giannoudis, Peter V

2013-02-01

The systemic response after fracture is regulated by a complex mechanism involving numerous growth factors. In this study, we analyzed the kinetics of key growth factors following lower-limb long bone fracture. Human serum was isolated from 15 patients suffering from lower-limb long bone fracture (tibia/femur) requiring surgical fixation. The levels of platelet-derived growth factor (PDGF-BB), vascular edothelial growth factor (VEGF), insulin growth factor-I (IGF-I), and transforming growth factor β1 (TGF-β1) were assayed by colorimetric ELISA at different time points during the first week after fracture. 10 healthy volunteers made up the control group of the study. Serum levels of the growth factors measured were compared to age, sex, and injury severity score. We found that there was a decline in the levels of PDGF-BB, IGF-I and TGF-β1 during the first 3 days after fracture. However, VEGF levels remained unchanged. The levels of all the growth factors studied then increased, with the highest concentrations noted at day 7 after surgery. No correlation was found between circulating levels of growth factors and age, injury severity score (ISS), blood loss, or fluid administration. There are systemic mitogenic and osteogenic signals after fracture. Important growth factors are released into the peripheral circulation, but early after surgery it appears that serum levels of key growth factors fall. By 7 days postoperatively, the levels had increased considerably. Our findings should be considered in cases where autologous serum is used for ex vivo expansion of mesenchymal stem cells. There should be further evaluation of the use of these molecules as biomarkers of bone union.

Regulation of human feto-placental endothelial barrier integrity by vascular endothelial growth factors: competitive interplay between VEGF-A165a, VEGF-A165b, PIGF and VE-cadherin.

PubMed

Pang, Vincent; Bates, David O; Leach, Lopa

2017-12-01

The human placenta nourishes and protects the developing foetus whilst influencing maternal physiology for fetal advantage. It expresses several members of the vascular endothelial growth factor (VEGF) family including the pro-angiogenic/pro-permeability VEGF-A 165 a isoform, the anti-angiogenic VEGF-A 165 b, placental growth factor (PIGF) and their receptors, VEGFR1 and VEGFR2. Alterations in the ratio of these factors during gestation and in complicated pregnancies have been reported; however, the impact of this on feto-placental endothelial barrier integrity is unknown. The present study investigated the interplay of these factors on junctional occupancy of VE-cadherin and macromolecular leakage in human endothelial monolayers and the perfused placental microvascular bed. Whilst VEGF-A 165 a (50 ng/ml) increased endothelial monolayer albumin permeability ( P <0.0001), equimolar concentrations of VEGF-A 165 b ( P >0.05) or PlGF ( P >0.05) did not. Moreover, VEGF-A 165 b (100 ng/ml; P <0.001) but not PlGF (100 ng/ml; P >0.05) inhibited VEGF-A 165 a-induced permeability when added singly. PlGF abolished the VEGF-A 165 b-induced reduction in VEGF-A 165 a-mediated permeability ( P >0.05); PlGF was found to compete with VEGF-A 165 b for binding to Flt-1 at equimolar affinity. Junctional occupancy of VE-cadherin matched alterations in permeability. In the perfused microvascular bed, VEGF-A 165 b did not induce microvascular leakage but inhibited and reversed VEGF-A 165 a-induced loss of junctional VE-cadherin and tracer leakage. These results indicate that the anti-angiogenic VEGF-A 165 b isoform does not increase permeability in human placental microvessels or HUVEC primary cells and can interrupt VEGF-A 165 a-induced permeability. Moreover, the interplay of these isoforms with PIGF (and s-flt1) suggests that the ratio of these three factors may be important in determining the placental and endothelial barrier in normal and complicated pregnancies. © 2017 The Author(s).

Pentoxifylline inhibits hypoxia-induced upregulation of tumor cell tissue factor and vascular endothelial growth factor.

PubMed

Amirkhosravi, A; Meyer, T; Warnes, G; Amaya, M; Malik, Z; Biggerstaff, J P; Siddiqui, F A; Sherman, P; Francis, J L

1998-10-01

Tissue factor (TF), the membrane glycoprotein that initiates blood coagulation, is constitutively expressed by many tumor cells and is implicated in peri-tumor fibrin deposition and hypercoagulability in cancer. Upregulation of tumor TF correlates with enhanced metastatic potential. Furthermore, TF has been colocalized with VEGF in breast cancer, specially at sites of early angiogenesis. There are no data on the effect of hypoxia on tumor cell TF expression. Since hypoxia is known to stimulate VEGF production, we studied whether this also induces tumor cell TF expression. Confluent monolayers of A375 melanoma, MCF-7 breast carcinoma and A549 lung carcinoma were cultured in either 95% air, 5% CO2 (normoxic) or 95% N2, 5% CO2 (hypoxic; 25-30 mmHg) for 24 h. Procoagulant activity (PCA) was measured by amidolytic and clotting assays, surface TF antigen by flow cytometry, early apoptosis by annexin V binding and VEGF levels in culture supernatants by ELISA. Hypoxia significantly increased tumor cell PCA in all three cell lines tested and TF antigen on A375 cells was increased four-fold (P <0.05). Pentoxifylline (PTX), a methylxanthine derivative, significantly inhibited the hypoxia-induced increase in PCA as well as VEGF release in all three cell lines tested. In A375 cells, PTX significantly inhibited TF antigen expression by both normoxic and hypoxic cells. Hypoxia induced a slight (5%) but not significant, increase in early apoptosis. Intravenous injection of hypoxic A375 cells into nude rats produced more pronounced thrombocytopenia (n = 5, P <0.01) and more lung metastases (n = 3, P <0.05) compared to normoxic cells. We conclude that hypoxia increases TF expression by malignant cells which enhances tumor cell-platelet binding and hematogenous metastasis. Hypoxia-induced upregulation of TF appears to parallel that of VEGF, although the mechanism remains unclear.

Coculture with endothelial cells enhances osteogenic differentiation of periodontal ligament stem cells via cyclooxygenase-2/prostaglandin E2/vascular endothelial growth factor signaling under hypoxia.

PubMed

Zhao, Lixing; Wu, Yeke; Tan, Lijun; Xu, Zhenrui; Wang, Jun; Zhao, Zhihe; Li, Xiaoyu; Li, Yu; Yang, Pu; Tang, Tian

2013-12-01

During periodontitis and orthodontic tooth movement, periodontal vasculature is severely impaired, leading to a hypoxic microenvironment of periodontal cells. However, the impact of hypoxia on periodontal cells is poorly defined. The present study investigates responses of cocultured endothelial cells (ECs) and periodontal ligament stem cells (PDLSCs) to hypoxia. Osteogenic differentiation, molecular characterization, and various behaviors of PDLSCs and human umbilical venous ECs under hypoxia were assessed by quantitative real-time reverse-transcription polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assay. Moreover, the effect of ECs on PDLSC osteogenic differentiation was tested using NS398 (cyclooxygenase 2 blocker), SU5416 (vascular endothelial growth factor [VEGF] receptor inhibitor), AH6809, L-798106, and L-161982 (EP1/2/3/4 antagonists). First, hypoxia promoted osteogenic differentiation in PDLSCs and enhanced EC migration, whereas PD98059 (extracellular signal-regulated protein kinase [ERK] inhibitor) blocked, and cocultured ECs further enhanced, hypoxia-induced osteogenic differentiation. Second, NS398 impaired EC migration and prostaglandin E2 (PGE2)/VEGF release, whereas cocultured PDLSCs and exogenous PGE2 partially reversed it. Third, NS398 (pretreated ECs) decreased PGE2/VEGF concentrations. NS398-treated ECs and AH6809/SU5416-treated PDLSCs impaired cocultured EC-induced enhancement of PDLSC osteogenic differentiation. Hypoxia enhances ERK-mediated osteogenic differentiation in PDLSCs. Coculture with EC further augments PDLSC osteogenic differentiation via cyclooxygenase-2/PGE2/VEGF signaling.

Rifaximin, a non-absorbable antibiotic, inhibits the release of pro-angiogenic mediators in colon cancer cells through a pregnane X receptor-dependent pathway.

PubMed

Esposito, Giuseppe; Gigli, Stefano; Seguella, Luisa; Nobile, Nicola; D'Alessandro, Alessandra; Pesce, Marcella; Capoccia, Elena; Steardo, Luca; Cirillo, Carla; Cuomo, Rosario; Sarnelli, Giovanni

2016-08-01

Activation of intestinal human pregnane X receptor (PXR) has recently been proposed as a promising strategy for the chemoprevention of inflammation-induced colon cancer. The present study was aimed at evaluating the effect of rifaximin, a non-absorbable antibiotic, in inhibiting angiogenesis in a model of human colorectal epithelium and investigating the role of PXR in its mechanism of action. Caco-2 cells were treated with rifaximin (0.1, 1.0 and 10.0 µM) in the presence or absence of ketoconazole (10 µM) and assessed for cell proliferation, migration and expression of proliferating cell nuclear antigen (PCNA). The release of vascular endothelial growth factor (VEGF) and nitric oxide (NO), expression of Akt, mechanistic target of rapamycin (mTOR), p38 mitogen activated protein kinases (MAPK), nuclear factor κB (NF-κB) and metalloproteinase-2 and -9 (MMP-2 and -9) were also evaluated. Treatment with rifaximin 0.1, 1.0 and 10.0 µM caused significant and concentration-dependent reduction of cell proliferation, cell migration and PCNA expression in the Caco-2 cells vs. untreated cells. Treatment downregulated VEGF secretion, NO release, VEGFR-2 expression, MMP-2 and MMP-9 expression vs. untreated cells. Rifaximin treatment also resulted in a concentration-dependent decrease in the phosphorylation of Akt, mTOR, p38MAPK and inhibition of hypoxia-inducible factor 1-α (HIF-1α), p70S6K and NF-κB. Ketoconazole (PXR antagonist) treatment inhibited these effects. These findings demonstrated that rifaximin causes PXR-mediated inhibition of angiogenic factors in Caco-2 cell line and may be a promising anticancer tool.

Therapeutic angiogenesis: angiogenic growth factors for ischemic heart disease.

PubMed

Henning, Robert J

2016-09-01

Stem cells encode vascular endothelial growth factors (VEGFs), fibroblastic growth factors (FGFs), stem cell factor, stromal cell-derived factor, platelet growth factor and angiopoietin that can contribute to myocardial vascularization. VEGFs and FGFs are the most investigated growth factors. VEGFs regulate angiogenesis and vasculogenesis. FGFs stimulate vessel cell proliferation and differentiation and are regulators of endothelial cell migration, proliferation and survival. Clinical trials of VEGF or FGF for myocardial angiogenesis have produced disparate results. The efficacy of therapeutic angiogenesis can be improved by: (1) identifying the most optimal patients; (2) increased knowledge of angiogenic factor pharmacokinetics and proper dose; (3) prolonging contact of angiogenic factors with the myocardium; (4) increasing the efficiency of VEGF or FGF gene transduction; and (5) utilizing PET or MRI to measure myocardial perfusion and perfusion reserve.

Vascular Endothelial Growth Factor and Angiopoietin are Required for Prostate Regeneration.

PubMed Central

Wang, Gui-min; Kovalenko, Bruce; Huang, Yili; Moscatelli, David

2007-01-01

BACKGROUND The regulation of the prostate size by androgens may be partly the result of androgen effects on the prostatic vasculature. We examined the effect of changes in androgen levels on the expression of a variety of angiogenic factors in the mouse prostate and determined if vascular endothelial growth factor (VEGF)-A and the angiopoietins are involved in the vascular response to androgens. METHODS Expression of angiogenic factors in prostate was quantitated using real-time PCR at different times after castration and after administration of testosterone to castrated mice. Angiopoietins were localized in prostate by immunohistochemistry and in situ hybridization. The roles of VEGF and the angiopoietins in regeneration of the prostate were examined in mice inoculated with cells expressing soluble VEGF receptor-2 or soluble Tie-2. RESULTS Castration resulted in a decrease in VEGF-A, VEGF-B, VEGF-C, placenta growth factor, FGF-2, and FGF-8 expression after one day. In contrast, VEGF-D mRNA levels increased. No changes in angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), hepatocyte growth factor, VEGF receptor-1, VEGF receptor-2 or tie-2 mRNA levels were observed. Administration of testosterone to castrated mice had the opposite effect on expression of these angiogenic factors. Ang-2 was expressed predominately in prostate epithelial cells whereas Ang-1 was expressed in epithelium and smooth muscle. Inoculation of mice with cells expressing soluble VEGF receptor-2 or Tie-2 blocked the increase in vascular density normally observed after administration of testosterone to castrated mice. The soluble receptors also blocked the increase in prostate weight and proliferation of prostatic epithelial cells. CONCLUSION VEGF-A and angiopoietins are required for the vascular response to androgens and for the ability of the prostate to regenerate in response to androgens. PMID:17221843

VEGF internalization is not required for VEGFR-2 phosphorylation in bioengineered surfaces with covalently linked VEGF

PubMed Central

Anderson, Sean M.; Shergill, Bhupinder; Barry, Zachary T.; Manousiouthakis, Eleana; Chen, Tom T.; Botvinick, Elliot; Platt, Manu O.; Iruela-Arispe, M. Luisa; Segura, Tatiana

2011-01-01

Vascular endothelial growth factor (VEGF) is known to activate proliferation, migration, and survival pathways in endothelial cells through phosphorylation of VEGF receptor-2 (VEGFR-2). VEGF has been incorporated into biomaterials through encapsulation, electrostatic sequestration, and covalent attachment, but the effect of these immobilization strategies on VEGF signaling has not been thoroughly investigated. Further, although growth factor internalization along with the receptor generally occurs in a physiological setting, whether this internalization is needed for receptor phosphorylation is not entirely clear. Here we show that VEGF covalently bound through a modified heparin molecule elicits an extended response of pVEGFR-2 in human umbilical vein endothelial cells (HUVECs) and that the covalent linkage reduces internalization of the growth factor during receptor endocytosis. Optical tweezer measurements show that the rupture force required to disrupt the heparin-VEGF-VEGFR-2 interaction increases from 3–8 pN to 6–12 pN when a covalent bond is introduced between VEGF and heparin. Importantly, by covalently binding VEGF to a heparin substrate, the stability (half-life) of VEGF is extended over three-fold. Here, mathematical models support the biological conclusions, further suggesting that VEGF internalization is significantly reduced when covalently bound, and indicating that VEGF is available for repeated phosphorylation events. PMID:21826315

Tuberculosis-diabetes co-morbidity is characterized by heightened systemic levels of circulating angiogenic factors

PubMed Central

Kumar, Nathella Pavan; Moideen, Kadar; Sivakumar, Shanmugam; Menon, Pradeep A; Viswanathan, Vijay; Kornfeld, Hardy; Babu, Subash

2016-01-01

Background Tuberculosis-diabetes co-morbidity (TB-DM) is characterized by increased inflammation with elevated circulating levels of inflammatory cytokines and other factors. Circulating angiogenic factors are intricately involved in the angiogenesis-inflammation nexus. Methods To study the association of angiogenic factors with TB-DM, we examined the systemic levels of VEGF-A, VEGF-C, VEGF-D, VEGF-R1, VEGF-R2, VEGF-R3 in individuals with either TB-DM (n=44) or TB alone (n=44). Results Circulating levels of VEGF-A, C, D, R1, R2 and R3 were significantly higher in TB-DM compared to TB individuals. Moreover, the levels of VEGF-A, C, R2 and/or R3 were significantly higher in TB-DM with bilateral or cavitary disease or with hemoptysis, suggesing an association with both disease severity and adverse clinical presentation. The levels of these factors also exhibited a significant positive relationship with bacterial burdens and HbA1c levels. In addition, VEGF-A, C and R2 levels were signifantly higher (at 2 months of treatment) in culture positive compared to culture negative TB-DM individuals. Finally, the circulating levels of VEGF-A, C, D, R1, R2 and R3 were significantly reduced following successful chemotherapy at 6 months. Conclusion Our data demonstrate that TB-DM is associated with heightened levels of circulating angiogenic factors, possibly reflecting both dysregulated angiogenesis and exaggerated inflammation. PMID:27717783

Irradiation-induced angiosarcoma and anti-angiogenic therapy: A therapeutic hope?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Azzariti, Amalia, E-mail: a.azzariti@oncologico.bari.it; Porcelli, Letizia; Mangia, Anita

2014-02-15

Angiosarcomas are rare soft-tissue sarcomas of endothelial cell origin. They can be sporadic or caused by therapeutic radiation, hence secondary breast angiosarcomas are an important subgroup of patients. Assessing the molecular biology of angiosarcomas and identify specific targets for treatment is challenging. There is currently great interest in the role of angiogenesis and of angiogenic factors associated with tumor pathogenesis and as targets for treatment of angiosarcomas. A primary cell line derived from a skin fragment of a irradiation-induced angiosarcoma patient was obtained and utilized to evaluate cell biomarkers CD31, CD34, HIF-1alpha and VEGFRs expression by immunocytochemistry and immunofluorescence, drugsmore » cytotoxicity by cell counting and VEGF release by ELISA immunoassay. In addition to previous biomarkers, FVIII and VEGF were also evaluated on tumor specimens by immunohistochemistry to further confirm the diagnosis. We targeted the VEGF–VEGFR-2 axis of tumor angiogenesis with two different class of vascular targeted drugs; caprelsa, the VEGFR-2/EGFR/RET inhibitor and bevacizumab the anti-VEGF monoclonal antibody. We found the same biomarkers expression either in tumor specimens and in the cell line derived from tumor. In vitro experiments demonstrated that angiogenesis plays a pivotal role in the progression of this tumor as cells displayed high level of VEGFR-2, HIF-1 alpha strongly accumulated into the nucleus and the pro-angiogenic factor VEGF was released by cells in culture medium. The evaluation of caprelsa and bevacizumab cytotoxicity demonstrated that both drugs were effective in inhibiting tumor proliferation. Due to these results, we started to treat the patient with pazopanib, which was the unique tyrosine kinase inhibitor available in Italy through a compassionate supply program, obtaining a long lasting partial response. Our data suggest that the study of the primary cell line could help physicians in choosing a therapeutic approach for patient that almost in vitro shows chances of success and that the anti-angiogenetic agents are a reliable therapeutic opportunity for angiosarcomas patients. - Highlights: • Characterization of a new AS cell line for VEGFR-2, HIF-1 alpha and VEGF. • Caprelsa and bevacizumab inhibit AS cells proliferation. • Anti-angiogenetic agents as a reliable therapeutic opportunity for AS patients.« less

Survival, differentiation, and neuroprotective mechanisms of human stem cells complexed with neurotrophin-3-releasing pharmacologically active microcarriers in an ex vivo model of Parkinson's disease.

PubMed

Daviaud, Nicolas; Garbayo, Elisa; Sindji, Laurence; Martínez-Serrano, Alberto; Schiller, Paul C; Montero-Menei, Claudia N

2015-06-01

Stem cell-based regenerative therapies hold great potential for the treatment of degenerative disorders such as Parkinson's disease (PD). We recently reported the repair and functional recovery after treatment with human marrow-isolated adult multilineage inducible (MIAMI) cells adhered to neurotrophin-3 (NT3) releasing pharmacologically active microcarriers (PAMs) in hemiparkinsonian rats. In order to comprehend this effect, the goal of the present work was to elucidate the survival, differentiation, and neuroprotective mechanisms of MIAMI cells and human neural stem cells (NSCs), both adhering to NT3-releasing PAMs in an ex vivo organotypic model of nigrostriatal degeneration made from brain sagittal slices. It was shown that PAMs led to a marked increase in MIAMI cell survival and neuronal differentiation when releasing NT3. A significant neuroprotective effect of MIAMI cells adhering to PAMs was also demonstrated. NSCs barely had a neuroprotective effect and differentiated mostly into dopaminergic neuronal cells when adhering to PAM-NT3. Moreover, those cells were able to release dopamine in a sufficient amount to induce a return to baseline levels. Reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay analyses identified vascular endothelial growth factor (VEGF) and stanniocalcin-1 as potential mediators of the neuroprotective effect of MIAMI cells and NSCs, respectively. It was also shown that VEGF locally stimulated tissue vascularization, which might improve graft survival, without excluding a direct neuroprotective effect of VEGF on dopaminergic neurons. These results indicate a prospective interest of human NSC/PAM and MIAMI cell/PAM complexes in tissue engineering for PD. Stem cell-based regenerative therapies hold great potential for the treatment of degenerative disorders such as Parkinson's disease (PD). The present work elucidates and compares the survival, differentiation, and neuroprotective mechanisms of marrow-isolated adult multilineage inducible cells and human neural stem cells both adhered to neurotrophin-3-releasing pharmacologically active microcarriers in an ex vivo organotypic model of PD made from brain sagittal slices. ©AlphaMed Press.

Modeling Vascularized Bone Regeneration Within a Porous Biodegradable CaP Scaffold Loaded with Growth Factors

PubMed Central

Sun, X; Kang, Y; Bao, J; Zhang, Y; Yang, Y; Zhou, X

2013-01-01

Osteogenetic microenvironment is a complex constitution in which extracellular matrix (ECM) molecules, stem cells and growth factors each interact to direct the coordinate regulation of bone tissue development. Importantly, angiogenesis improvement and revascularization are critical for osteogenesis during bone tissue regeneration processes. In this study, we developed a three-dimensional (3D) multi-scale system model to study cell response to growth factors released from a 3D biodegradable porous calcium phosphate (CaP) scaffold. Our model reconstructed the 3D bone regeneration system and examined the effects of pore size and porosity on bone formation and angiogenesis. The results suggested that scaffold porosity played a more dominant role in affecting bone formation and angiogenesis compared with pore size, while the pore size could be controlled to tailor the growth factor release rate and release fraction. Furthermore, a combination of gradient VEGF with BMP2 and Wnt released from the multi-layer scaffold promoted angiogenesis and bone formation more readily than single growth factors. These results demonstrated that the developed model can be potentially applied to predict vascularized bone regeneration with specific scaffold and growth factors. PMID:23566802

Loss of epigenetic Kruppel-like factor 4 histone deacetylase (KLF-4-HDAC)-mediated transcriptional suppression is crucial in increasing vascular endothelial growth factor (VEGF) expression in breast cancer.

PubMed

Ray, Alpana; Alalem, Mohamed; Ray, Bimal K

2013-09-20

Vascular endothelial growth factor (VEGF) is recognized as an important angiogenic factor that promotes angiogenesis in a series of pathological conditions, including cancer, inflammation, and ischemic disorders. We have recently shown that the inflammatory transcription factor SAF-1 is, at least in part, responsible for the marked increase of VEGF levels in breast cancer. Here, we show that SAF-1-mediated induction of VEGF is repressed by KLF-4 transcription factor. KLF-4 is abundantly present in normal breast epithelial cells, but its level is considerably reduced in breast cancer cells and clinical cancer tissues. In the human VEGF promoter, SAF-1- and KLF-4-binding elements are overlapping, whereas SAF-1 induces and KLF-4 suppresses VEGF expression. Ectopic overexpression of KLF-4 and RNAi-mediated inhibition of endogenous KLF-4 supported the role of KLF-4 as a transcriptional repressor of VEGF and an inhibitor of angiogenesis in breast cancer cells. We show that KLF-4 recruits histone deacetylases (HDACs) -2 and -3 at the VEGF promoter. Chronological ChIP assays demonstrated the occupancy of KLF-4, HDAC2, and HDAC3 in the VEGF promoter in normal MCF-10A cells but not in MDA-MB-231 cancer cells. Co-transfection of KLF-4 and HDAC expression plasmids in breast cancer cells results in synergistic repression of VEGF expression and inhibition of angiogenic potential of these carcinoma cells. Together these results identify a new mechanism of VEGF up-regulation in cancer that involves concomitant loss of KLF-4-HDAC-mediated transcriptional repression and active recruitment of SAF-1-mediated transcriptional activation.

Vascular endothelial growth factor-C (VEGF-C) expression predicts lymph node metastasis of transitional cell carcinoma of the bladder.

PubMed

Suzuki, Kazumi; Morita, Tatsuo; Tokue, Akihiko

2005-02-01

It has been found that expression of vascular endothelial growth factor-C (VEGF-C) in several carcinomas is significantly associated with angiogenesis, lymphangiogenesis and regional lymph node metastasis. However, VEGF-C expression in bladder transitional cell carcinoma (TCC) has not yet been reported. To elucidate the role of VEGF-C in bladder TCC, we examined VEGF-C expression in bladder TCC and pelvic lymph node metastasis specimens obtained from patients who underwent radical cystectomy. Eighty-seven patients who underwent radical cystectomy for clinically organ-confined TCC of the bladder were enrolled in the present study. No neoadjuvant treatments, except transurethral resection of the tumor, were given to these patients. The VEGF-C expressions of 87 bladder tumors and 20 pelvic lymph node metastasis specimens were examined immunohistochemically and the association between VEGF-C expression and clinicopathological factors, including angiogenesis as evaluated by microvessel density (MVD), was also examined. Vascular endothelial growth factor-C expression was found in the cytoplasm of tumor cells, but not in the normal transitional epithelium. Vascular endothelial growth factor-C expression was significantly associated with the pathological T stage (P = 0.0289), pelvic lymph node metastasis (P < 0.0001), lymphatic involvement (P = 0.0008), venous involvement (P = 0.0002) and high MVD (P = 0.0043). The multivariate analysis demonstrated that VEGF-C expression and high MVD in bladder TCC were independent risk factors influencing the pelvic lymph node metastasis. Moreover, the patients with VEGF-C-positive tumors had significantly poorer prognoses than those with the VEGF-C-negative tumors (P = 0.0087) in the univariate analysis. The multivariate analysis based on Cox proportional hazard model showed that the independent prognostic factors were patient age (P = 0.0132) and pelvic lymph node metastasis (P = 0.0333). The present study suggests that VEGF-C expression is an important predictive factor of pelvic lymph node metastasis in bladder cancer patients.

Human Herpesvirus-8-Transformed Endothelial Cells Have Functionally Activated Vascular Endothelial Growth Factor/Vascular Endothelial Growth Factor Receptor

PubMed Central

Masood, Rizwan; Cesarman, Ethel; Smith, D. Lynne; Gill, Parkash S.; Flore, Ornella

2002-01-01

Kaposi’s sarcoma is a vascular tumor commonly associated with human immunodeficiency virus (HIV)-1 and human herpesvirus (HHV-8) also known as Kaposi’s sarcoma-associated herpesvirus. The principal features of this tumor are abnormal proliferation of vascular structures lined with spindle-shaped endothelial cells. HHV-8 may transform a subpopulation of endothelial cells in vitro via viral and cellular gene expression. We hypothesized that among the cellular genes, vascular endothelial growth factors (VEGFs) and their cognate receptors may be involved in viral-mediated transformation. We have shown that HHV-8-transformed endothelial cells (EC-HHV-8) express higher levels of VEGF, VEGF-C, VEGF-D, and PlGF in addition to VEGF receptors-1, -2, and -3. Furthermore, antibodies to VEGF receptor-2 inhibited cell proliferation and viability. Similarly, inhibition of VEGF gene expression with antisense oligonucleotides inhibited EC-HHV-8 cell proliferation/viability. The growth and viability of primary endothelial cells and a fibroblast cell line however were unaffected by either the VEGF receptor-2 antibody or the VEGF antisense oligodeoxynucleotides. VEGF and VEGF receptors are thus induced in EC-HHV-8 and participate in the transformation. Inhibitors of VEGF may thus modulate the disease process during development and progression. PMID:11786394

Activation of PPARbeta/delta induces endothelial cell proliferation and angiogenesis.

PubMed

Piqueras, Laura; Reynolds, Andrew R; Hodivala-Dilke, Kairbaan M; Alfranca, Arántzazu; Redondo, Juan M; Hatae, Toshihisa; Tanabe, Tadashi; Warner, Timothy D; Bishop-Bailey, David

2007-01-01

The role of the nuclear receptor peroxisome-proliferator activated receptor (PPAR)-beta/delta in endothelial cells remains unclear. Interestingly, the selective PPARbeta/delta ligand GW501516 is in phase II clinical trials for dyslipidemia. Here, using GW501516, we have assessed the involvement of PPARbeta/delta in endothelial cell proliferation and angiogenesis. Western blot analysis indicated PPARbeta/delta was expressed in primary human umbilical and aortic endothelial cells, and in the endothelial cell line, EAHy926. Treatment with GW501516 increased human endothelial cell proliferation and morphogenesis in cultures in vitro, endothelial cell outgrowth from murine aortic vessels in vitro, and angiogenesis in a murine matrigel plug assay in vivo. GW501516 induced vascular endothelial cell growth factor mRNA and peptide release, as well as adipose differentiation-related protein (ADRP), a PPARbeta/delta target gene. GW501516-induced proliferation, morphogenesis, vascular endothelial growth factor (VEGF), and ADRP were absent in endothelial cells transfected with dominant-negative PPARbeta/delta. Furthermore, treatment of cells with cyclo-VEGFI, a VEGF receptor1/2 antagonist, abolished GW501516-induced endothelial cell proliferation and tube formation. PPARbeta/delta is a novel regulator of endothelial cell proliferation and angiogenesis through VEGF. The use of GW501516 to treat dyslipidemia may need to be carefully monitored in patients susceptible to angiogenic disorders.

Tumor necrosis factor-α promotes the lymphangiogenesis of gallbladder carcinoma through nuclear factor-κB-mediated upregulation of vascular endothelial growth factor-C

PubMed Central

Du, Qiang; Jiang, Lei; Wang, Xiaoqian; Wang, Meiping; She, Feifei; Chen, Yanling

2014-01-01

Vascular endothelial growth factor (VEGF)-C is an important lymphangiogenic factor involved in the lymphangiogenesis of gallbladder carcinoma (GBC) and the lymph node metastasis of the tumor. Tumor necrosis factor (TNF)-α, a key inflammatory cytokine responding to chronic inflammation of GBC, has been reported to stimulate the expression of VEGF-C in some nonneoplastic cells. But whether TNF-α promotes the expression of VEGF-C in GBC has yet to be determined. Therefore, in the present study, the concentration of TNF-α and VEGF-C and the lymphatic vessel density (LVD) in the clinical GBC specimens were analyzed, and a linear correlation was found between the concentration of TNF-α and that of VEGF-C, the lymphatic vessel density (LVD); The transcription and protein level of VEGF-C in NOZ cell line were detected by real-time polymerase chain reaction (PCR) and enzyme linked immunosorbent assay (ELISA), and TNF-α enhanced the expression of VEGF-C in NOZ cell lines in a dose and time-dependent manner. Lymphatic tube formation in vitro was observed in a three-dimensional coculture system consisting of HDLECs and NOZ cell lines, and lymphatic vessels of GBC in nude mice model was detected by immunohistochemistry. TNF-α promoted the tube formation of lymphatic endothelial cells in vitro and the lymphangiogenesis of GBC in nude mice; The nuclear factor (NF)-κB binding site on the VEGF-C promoter was identified using Site-directed mutagenesis, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation assay (ChIP). Taken together, TNF-α can upregulate the expression of VEGF-C and promote the lymphangiogenesis of GBC via NF-κB combining with the promoter of VEGF-C. PMID:25154789

Neo-vascularization of the stroke cavity by implantation of human neural stem cells on VEGF-releasing PLGA microparticles

PubMed Central

Bible, Ellen; Qutachi, Omar; Chau, David Y.S.; Alexander, Morgan R.; Shakesheff, Kevin M.; Modo, Michel

2012-01-01

Replacing the tissue lost after a stroke potentially provides a new neural substrate to promote recovery. However, significant neurobiological and biotechnological challenges need to be overcome to make this possibility into a reality. Human neural stem cells (hNSCs) can differentiate into mature brain cells, but require a structural support that retains them within the cavity and affords the formation of a de novo tissue. Nevertheless, in our previous work, even after a week, this primitive tissue is void of a vasculature that could sustain its long-term viability. Therefore, tissue engineering strategies are required to develop a vasculature. Vascular endothelial growth factor (VEGF) is known to promote the proliferation and migration of endothelial cells during angio- and arteriogenesis. VEGF by itself here did not affect viability or differentiation of hNSCs, whereas growing cells on poly(D,L-lactic acid-co-glycolic acid) (PLGA) microparticles, with or without VEGF, doubled astrocytic and neuronal differentiation. Secretion of a burst and a sustained delivery of VEGF from the microparticles in vivo attracted endothelial cells from the host into this primate tissue and in parts established a neovasculature, whereas in other parts endothelial cells were merely interspersed with hNSCs. There was also evidence of a hypervascularization indicating that further work will be required to establish an adequate level of vascularization. It is therefore possible to develop a putative neovasculature within de novo tissue that is forming inside a tissue cavity caused by a stroke. PMID:22818980

Review and update of intraocular therapy in noninfectious uveitis.

PubMed

Sallam, Ahmed; Taylor, Simon R J; Lightman, Sue

2011-11-01

To review new clinically relevant data regarding the intraocular treatment of noninfectious uveitis. Triamcinolone acetonide, the most commonly used intravitreal corticosteroid for treatment of uveitis and uveitic macular oedema has a limited duration of action and is associated with a high risk of corticosteroid-induced intraocular pressure (IOP) rise and cataract. Recent advances have led to the development of sustained-release corticosteroid devices using different corticosteroids such as dexamethasone and fluocinolone acetonide. Treatment options for patients who have previously exhibited corticosteroid hypertensive response have also expanded through the use of new noncorticosteroid intravitreal therapeutics such as methotrexate and antivascular endothelial growth factor (anti-VEGF) agents. Ozurdex dexamethasone implant appears to have a better safety profile, and a slightly long-lasting effect than triamcinolone acetonide. The Retisert implant allows the release of corticosteroids at a constant rate for 2.5 years, but it requires surgical placement and its use is associated with a very high risk of cataract and requirement for IOP-lowering surgery. For patients who are steroid responders, methotrexate may offer a better alternative to corticosteroid treatment than anti-VEGF agents, but controlled trials are required to confirm this.

Controllable mineral coatings on PCL scaffolds as carriers for growth factor release

PubMed Central

Suárez-González, Darilis; Barnhart, Kara; Migneco, Francesco; Flanagan, Colleen; Hollister, Scott J.; Murphy, William L.

2011-01-01

In this study, we have developed mineral coatings on polycaprolactone scaffolds to serve as templates for growth factor binding and release. Mineral coatings were formed using a biomimetic approach that consisted in the incubation of scaffolds in modified simulated body fluids (mSBF). To modulate the properties of the mineral coating, which we hypothesized would dictate growth factor release, we used carbonate (HCO3) concentration in mSBF of 4.2 mM, 25mM, and 100mM. Analysis of the mineral coatings formed using scanning electron microscopy indicated growth of a continuous layer of mineral with different morphologies. X-ray diffraction analysis showed peaks associated with hydroxyapatite, the major inorganic constituent of human bone tissue in coatings formed in all HCO3 concentrations. Mineral coatings with increased HCO3 substitution showed more rapid dissolution kinetics in an environment deficient in calcium and phosphate but showed re-precipitation in an environment with the aforementioned ions. The mineral coating provided an effective mechanism for growth factor binding and release. Peptide versions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2) were bound with efficiencies up to 90% to mineral mineral-coated PCL scaffolds. We also demonstrated sustained release of all growth factors with release kinetics that were strongly dependent in the solubility of the mineral coating. PMID:22014948

Novel vascular endothelial growth factor blocker improves cellular viability and reduces hypobaric hypoxia-induced vascular leakage and oedema in rat brain.

PubMed

Saraswat, Deepika; Nehra, Sarita; Chaudhary, Kamal; CVS, Siva Prasad

2015-05-01

Vascular endothelial growth factor (VEGF) is an important cerebral angiogenic and permeability factor under hypoxia. There is a need to find effective molecules that may ameliorate hypoxia-induced cerebral oedema. In silico identification of novel candidate molecules that block VEGF-A site were identified and validated with a Ramachandran plot. The active site residues of VEGF-A were detected by Pocketfinder, CASTp, and DogSiteScorer. Based on in silico data, three VEGF-A blocker (VAB) candidate molecules (VAB1, VAB2, and VAB3) were checked for improvement in cellular viability and regulation of VEGF levels in N2a cells under hypoxia (0.5% O2 ). Additionally, the best candidate molecule's efficacy was assessed in male Sprague-Dawley rats for its ameliorative effect on cerebral oedema and vascular leakage under hypobaric hypoxia 7260 m. All experimental results were compared with the commercially available VEGF blocker sunitinib. Vascular endothelial growth factor-A blocker 1 was found most effective in increasing cellular viability and maintaining normal VEGF levels under hypoxia (0.5% oxygen) in N2a cells. Vascular endothelial growth factor-A blocker 1 effectively restored VEGF levels, decreased cerebral oedema, and reduced vascular leakage under hypobaric hypoxia when compared to sunitinib-treated rats. Vascular endothelial growth factor-A blocker 1 may be a promising candidate molecule for ameliorating hypobaric hypoxia-induced vasogenic oedema by regulating VEGF levels. © 2015 Wiley Publishing Asia Pty Ltd.

Experimental variation of the level and the ratio of angiogenic and osteogenic signaling affects the spatiotemporal expression of bone-specific markers and organization of bone formation in ectopic sites.

PubMed

Moser, Norman; Goldstein, Jan; Kauffmann, Phillip; Epple, Matthias; Schliephake, Henning

2018-04-01

The aim of the present study was to test the hypothesis that the ratio of angiogenic and osteogenic signaling affects ectopic bone formation when delivered in different amounts. Porous composite PDLLA/CaCO 3 scaffolds were loaded with rhBMP2 and rhVEGF in different dosage combinations and implanted into the gluteal muscles of 120 adult male Wistar rats. Bone formation and expression of alkaline phosphatase and Runx2 were quantified by histomorphometry. Spatial distribution across the scaffolds was assessed by using a grid that discriminated between the periphery and center of the scaffolds. The evaluation showed that the combined delivery of bone morphogenetic protein BMP2 and VEGF in different dosage combinations did not enhance the overall quantity of ectopic bone formation compared to the delivery of BMP2 alone. The addition of VEGF generally upregulated Runx2 after 4 weeks, which may have retarded terminal osteogenic differentiation. However, slow combined delivery of 1.5-2.0 μg BMP2 combined with 50 ng VEGF165 over a period of 5 weeks supported a more even distribution of bone formation across the implanted scaffolds whereas higher amounts of VEGF did not elicit this effect. The findings suggest that structural organization rather than the quantity of ectopic bone formation is affected by the dosage and the ratio of BMP2 and VEGF levels at the observed intervals. The development of carriers for dual growth factor delivery has to take into account the necessity to carefully balance the ratio of growth release.

Plasma and platelet-derived vascular endothelial growth factor and angiopoietin-1 in hypertension: effects of antihypertensive therapy.

PubMed

Nadar, S K; Blann, A D; Lip, G Y H

2004-10-01

Platelets carry angiogenic growth factors vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1). Although platelet-derived growth factors are important in the pathogenesis and metastasis of malignancy, their role in the pathogenesis of complications and the response to treatment in hypertension is less known. To test the hypotheses that there are differences in VEGF and Ang-1 in the plasma and within platelets from patients with hypertension, and that levels change with successful treatment. We recruited 42 previously untreated patients with hypertension (25 male; mean age 53 years) and 30 age- and sex-matched controls. Plasma VEGF, Ang-1 and soluble P-selectin (sPsel, an index of platelet activation), and total platelet [platelet VEGF (pVEGF) and platelet Ang-1 (pAng-1)] were measured by ELISA. The patients were then treated for 6 months with amlodipine-based antihypertensive therapy, achieving a mean blood pressure below 140/80 mmHg. Patients with hypertension had significantly higher levels of plasma sPsel (P =0.01), VEGF (P < 0.001) and Ang-1 (P = 0.01), as well as pVEGF (P < 0.001) and pAng-1 (P =0.02). The levels of plasma and platelet angiogenic growth factors were significantly reduced after antihypertensive treatment (VEGF, P = 0.01; pVEGF, P < 0.001; Ang-1, P < 0.001; pAng-1, P = 0.04). There were no correlations with blood pressure or the levels of sPsel. Levels of plasma and intra-platelet VEGF and Ang-1 are increased in hypertension and are decreased with treatment. Platelet levels of VEGF and Ang-1 may be related to platelet activation but may also involve other mechanisms (for example, the general vascular and haemodynamic changes) that are seen in hypertension.

A virally inactivated functional growth factor preparation from human platelet concentrates.

PubMed

Su, C-Y; Kuo, Y P; Lin, Y C; Huang, C-T; Tseng, Y H; Burnouf, T

2009-08-01

Human platelet growth factors (HPGF) are essential for tissue regeneration and may replace fetal bovine serum (FBS) in cell therapy. No method for the manufacture of standardized virally inactivated HPGF has been developed yet. Platelet concentrates (PC) were subjected to solvent/detergent (S/D) treatment (1% TnBP/1% Triton X-45), oil extraction, hydrophobic interaction chromatography and sterile filtration. Platelet-derived growth factor (PDGF)-AB, -BB and -AA, transforming growth factor-beta1 (TGF-beta1), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1) and vascular endothelium growth factor (VEGF) were measured by ELISA. Composition in proteins and lipids was determined, protein profiles were obtained by SDS-PAGE, and TnBP and Triton X-45 were assessed by gas chromatography and high-performance liquid chromatography, respectively. Cell growth promoting activity of HPGF was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay using human embryonic kidney (HEK293A) fibroblast and Statens Seruminstitute rabbit corneal (SIRC) epithelial cell lines. The GF preparation contained a mean of 16.66, 2.04, 1.53, 72.19, 0.33, 48.59 and 0.44 ng/ml of PDGF-AB, -BB, -AA, TGF-beta1, EGF, IGF-1 and VEGF, respectively. The protein profile was typical of platelet releasates and had less than 2 p.p.m. of residual S/D agents. MTS assay of HEK293A and SIRC cultures showed that the GF preparation at 10% and 0.1% (v/v), respectively, could successfully replace 10% FBS for cell proliferation. Cell-stimulating activity of HPGF on HEK293A was over twice that of PC releasates. STANDARDIZED and functional virally inactivated HPGF can be prepared from human PC for possible applications in cell therapy and regenerative medicine.

Identification of functional VEGF receptors on human platelets.

PubMed

Selheim, Frode; Holmsen, Holm; Vassbotn, Flemming S

2002-02-13

Platelets secrete platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) upon stimulation. We have demonstrated that platelets have functionally active PDGF alpha-receptors, a transmembrane tyrosine kinase involved in negative feedback regulation. Here we demonstrate the presence of the related VEGF receptors fms-like tyrosine kinase-1 and kinase-insert domain region on human platelets. VEGF itself did not cause platelet aggregation. However, addition of exogenous VEGF to SFRLLN or thrombin-stimulated platelets potentiated platelet aggregation. Moreover, thrombin-induced phosphoinositide 3-kinase and mitogen-activated protein kinase activity were enhanced in the presence of VEGF.

Increased expression of VEGF121/VEGF165-189 ratio results in a significant enhancement of human prostate tumor angiogenesis.

PubMed

Catena, Raul; Muniz-Medina, Vanessa; Moralejo, Beatriz; Javierre, Biola; Best, Carolyn J M; Emmert-Buck, Michael R; Green, Jeffrey E; Baker, Carl C; Calvo, Alfonso

2007-05-15

Vascular endothelial growth factor (VEGF) is a proangiogenic factor upregulated in many tumors. The alternative splicing of VEGF mRNA renders 3 major isoforms of 121, 165 and 189 amino-acids in humans (1 less amino-acid for each mouse VEGF isoform). We have designed isoform specific real time QRT-PCR assays to quantitate VEGF transcripts in mouse and human normal and malignant prostates. In the human normal prostate, VEGF(165) was the predominant isoform (62.8% +/- 5.2%), followed by VEGF(121) (22.5% +/- 6.3%) and VEGF(189) (p < 0.001) (14.6% +/- 2.1%). Prostate tumors showed a significant increase in the percentage of VEGF(121) and decreases in VEGF(165) (p < 0.01) and VEGF(189) (p < 0.05). However, the amount of total VEGF mRNA was similar between normal and malignant prostates. VEGF(164) was the transcript with the highest expression in the mouse normal prostate. Unlike human prostate cancer, tumors from TRAMP mice demonstrated a significant increase in total VEGF mRNA levels and in each of the VEGF isoforms, without changes in the relative isoform ratios. Morpholino phosphorodiamide antisense oligonucleotide technology was used to increase the relative amount of VEGF(121) while proportionally decreasing VEGF(165) and VEGF(189) levels in human prostate cell lines, through the modification of alternative splicing, without changing transcription levels and total amount of VEGF. The increase in the VEGF(121)/VEGF(165-189) ratio in PC3 cells resulted in a dramatic increase in prostate tumor angiogenesis in vivo. Our results underscore the importance of VEGF(121) in human prostate carcinoma and demonstrate that the relative expression of the different VEGF isoforms has an impact on prostate carcinogenesis. (c) 2007 Wiley-Liss, Inc.

Induction of angiogenesis in tissue-engineered scaffolds designed for bone repair: a combined gene therapy-cell transplantation approach.

PubMed

Jabbarzadeh, Ehsan; Starnes, Trevor; Khan, Yusuf M; Jiang, Tao; Wirtel, Anthony J; Deng, Meng; Lv, Qing; Nair, Lakshmi S; Doty, Steven B; Laurencin, Cato T

2008-08-12

One of the fundamental principles underlying tissue engineering approaches is that newly formed tissue must maintain sufficient vascularization to support its growth. Efforts to induce vascular growth into tissue-engineered scaffolds have recently been dedicated to developing novel strategies to deliver specific biological factors that direct the recruitment of endothelial cell (EC) progenitors and their differentiation. The challenge, however, lies in orchestration of the cells, appropriate biological factors, and optimal factor doses. This study reports an approach as a step forward to resolving this dilemma by combining an ex vivo gene transfer strategy and EC transplantation. The utility of this approach was evaluated by using 3D poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds for bone tissue engineering applications. Our goal was achieved by isolation and transfection of adipose-derived stromal cells (ADSCs) with adenovirus encoding the cDNA of VEGF. We demonstrated that the combination of VEGF releasing ADSCs and ECs results in marked vascular growth within PLAGA scaffolds. We thereby delineate the potential of ADSCs to promote vascular growth into biomaterials.

Induction of angiogenesis in tissue-engineered scaffolds designed for bone repair: A combined gene therapy–cell transplantation approach

PubMed Central

Jabbarzadeh, Ehsan; Starnes, Trevor; Khan, Yusuf M.; Jiang, Tao; Wirtel, Anthony J.; Deng, Meng; Lv, Qing; Nair, Lakshmi S.; Doty, Steven B.; Laurencin, Cato T.

2008-01-01

One of the fundamental principles underlying tissue engineering approaches is that newly formed tissue must maintain sufficient vascularization to support its growth. Efforts to induce vascular growth into tissue-engineered scaffolds have recently been dedicated to developing novel strategies to deliver specific biological factors that direct the recruitment of endothelial cell (EC) progenitors and their differentiation. The challenge, however, lies in orchestration of the cells, appropriate biological factors, and optimal factor doses. This study reports an approach as a step forward to resolving this dilemma by combining an ex vivo gene transfer strategy and EC transplantation. The utility of this approach was evaluated by using 3D poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds for bone tissue engineering applications. Our goal was achieved by isolation and transfection of adipose-derived stromal cells (ADSCs) with adenovirus encoding the cDNA of VEGF. We demonstrated that the combination of VEGF releasing ADSCs and ECs results in marked vascular growth within PLAGA scaffolds. We thereby delineate the potential of ADSCs to promote vascular growth into biomaterials. PMID:18678895

Heparin-Based Coacervate of FGF2 Improves Dermal Regeneration by Asserting a Synergistic Role with Cell Proliferation and Endogenous Facilitated VEGF for Cutaneous Wound Healing.

PubMed

Wu, Jiang; Ye, Jingjing; Zhu, Jingjing; Xiao, Zecong; He, Chaochao; Shi, Hongxue; Wang, Yadong; Lin, Cai; Zhang, Hongyu; Zhao, Yingzheng; Fu, Xiaobing; Chen, Hong; Li, Xiaokun; Li, Lin; Zheng, Jie; Xiao, Jian

2016-06-13

Effective wound healing requires complicated, coordinated interactions and responses at protein, cellular, and tissue levels involving growth factor expression, cell proliferation, wound closure, granulation tissue formation, and vascularization. In this study, we develop a heparin-based coacervate consisting of poly(ethylene argininylaspartate digylceride) (PEAD) as a storage matrix, heparin as a bridge, and fibroblast growth factor-2 (FGF2) as a cargo (namely heparin-FGF2@PEAD) for wound healing. First, in vitro characterization demonstrates the loading efficiency and control release of FGF2 from the heparin-FGF2@PEAD coacervate. The following in vivo studies examine the wound healing efficiency of the heparin-FGF2@PEAD coacervate upon delivering FGF2 to full-thickness excisional skin wounds in vivo, in comparison with the other three control groups with saline, heparin@PEAD as vehicle, and free FGF2. Collective in vivo data show that controlled release of FGF2 to the wounds by the coacervate significantly accelerates the wound healing by promoting cell proliferation, stimulating the secretion of vascular endothelial growth factor (VEGF) for re-epithelization, collagen deposition, and granulation tissue formation, and enhancing the expression of platelet endothelial cell adhesion molecule (CD31) and alpha-smooth muscle actin (α-SMA) for blood vessel maturation. In parallel, no obvious wound healing effect is found for the control, vehicle, and free FGF2 groups, indicating the important role of the coavervate in the wound healing process. This work designs a suitable delivery system that can protect and release FGF2 in a sustained and controlled manner, which provides a promising therapeutic potential for topical treatment of wounds.

Characterization of two types of vascular endothelial growth factor from Litopenaeus vannamei and their involvements during WSSV infection.

PubMed

Wang, Zhiwei; Li, Shihao; Li, Fuhua; Yang, Hui; Yang, Fusheng; Xiang, Jianhai

2015-12-01

Vascular endothelial growth factors (VEGFs) are important signaling proteins in VEGF signaling pathway which play key roles in inducing endothelial cell proliferation, migration, angiogenesis, vascular permeability, inhibition of apoptosis and virus infection. In the present study, we isolated and characterized two VEGF genes, LvVEGF1 and LvVEGF2 from Litopenaeus vannamei. The deduced amino acid sequences of both LvVEGF1 and LvVEGF2 contained a signal peptide, a typical PDGF/VEGF domain and a cysteine knot motif (CXCXC). Tissue distribution analysis showed that LvVEGF1 was predominantly expressed in lymphoid organ (Oka) while LvVEGF2 was mainly detected in gill and hemocytes. The transcriptional levels of LvVEGF1 in Oka and LvVEGF2 in gill or hemocytes were apparently up-regulated during WSSV infection. Double-stranded RNA interference was used for further functional studies. The data showed that silencing of LvVEGF1 and LvVEGF2 caused a decrease of the copy numbers of the virus in WSSV infected shrimp and a reduction of the cumulative mortality rate of shrimp during WSSV infection. The present study indicated that LvVEGF1 and LvVEGF2 might facilitate WSSV infection, which provided new evidence to understand the function of VEGF signaling pathway during WSSV infection in shrimp. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synaptic loss and firing alterations in Axotomized Motoneurons are restored by vascular endothelial growth factor (VEGF) and VEGF-B.

PubMed

Calvo, Paula M; de la Cruz, Rosa R; Pastor, Angel M

2018-06-01

Vascular endothelial growth factor (VEGF), also known as VEGF-A, was discovered due to its vasculogenic and angiogenic activity, but a neuroprotective role for VEGF was later proven for lesions and disorders. In different models of motoneuronal degeneration, VEGF administration leads to a significant reduction of motoneuronal death. However, there is no information about the physiological state of spared motoneurons. We examined the trophic role of VEGF on axotomized motoneurons with recordings in alert animals using the oculomotor system as the experimental model, complemented with a synaptic study at the confocal microscopy level. Axotomy leads to drastic alterations in the discharge characteristics of abducens motoneurons, as well as to a substantial loss of their synaptic inputs. Retrograde delivery of VEGF completely restored the discharge activity and synaptically-driven signals in injured motoneurons, as demonstrated by correlating motoneuronal firing rate with motor performance. Moreover, VEGF-treated motoneurons recovered a normal density of synaptic boutons around motoneuronal somata and in the neuropil, in contrast to the low levels of synaptic terminals found after axotomy. VEGF also reduced the astrogliosis induced by axotomy in the abducens nucleus to control values. The administration of VEGF-B produced results similar to those of VEGF. This is the first work demonstrating that VEGF and VEGF-B restore the normal operating mode and synaptic inputs on injured motoneurons. Altogether these data indicate that these molecules are relevant synaptotrophic factors for motoneurons and support their clinical potential for the treatment of motoneuronal disorders. Copyright © 2018 Elsevier Inc. All rights reserved.

VEGF is a chemoattractant for FGF-2–stimulated neural progenitors

PubMed Central

Zhang, Huanxiang; Vutskits, Laszlo; Pepper, Michael S.; Kiss, Jozsef Z.

2003-01-01

Mmigration of undifferentiated neural progenitors is critical for the development and repair of the nervous system. However, the mechanisms and factors that regulate migration are not well understood. Here, we show that vascular endothelial growth factor (VEGF)-A, a major angiogenic factor, guides the directed migration of neural progenitors that do not display antigenic markers for neuron- or glia-restricted precursor cells. We demonstrate that progenitor cells express both VEGF receptor (VEGFR) 1 and VEGFR2, but signaling through VEGFR2 specifically mediates the chemotactic effect of VEGF. The expression of VEGFRs and the chemotaxis of progenitors in response to VEGF require the presence of fibroblast growth factor 2. These results demonstrate that VEGF is an attractive guidance cue for the migration of undifferentiated neural progenitors and offer a mechanistic link between neurogenesis and angiogenesis in the nervous system. PMID:14691144

[Investigation of mechanisms of action of growth factors of autologous platelet-rich plasma used to treat erectile dysfunction].

PubMed

Epifanova, M V; Chalyi, M E; Krasnov, A O

2017-09-01

To determine the quantitative and qualitative composition of growth factors (PDGF-AA, PDGF-BB, VEGF, VEGF-D, FGF-acid, FGF-basic) and platelets in various modifications of APRP. Blood of 12 male volunteers (control group) and 12 patients with ED was used to prepare APRP and the subsequently determine the concentration of growth factors. The growth factor concentrations (FGF acid, FGF basic, PDGF-AA, PDGF-BB, VEGF, VEGF-D) was determined using a flow cytometry-based xMAP Luminex (Gen-Probe) system. Concentration of platelets in APRP obtained by two stage centrifugation, reached 1480 (1120-1644) in the control group and 1232 (956-1502) in patients with ED. The concentration of growth factors in the samples prepared without preliminary freezing was: PDGF-AA 842 (22-3700), PDGF-BB 2837 (1460-4100), FGF-basic 7.9 (0.28-127), FGF-acid 3, 4 (0.14-11), VEGF 19 (4.6-46), VEGF-D 21 (14-38). After thawing, the concentration of all growth factors in the samples increased. The study findings suggest that the mechanism of erectile function recovery following the use of APRP is through the active substances detected in APRP, i.e. FGF-basic, PDGF-AA, PDGF-BB, VEGF, VEGF-D and FGF-acid. Also, the study showed that the content of growth factors in APRP after of freezing/thawing is higher than in APRP that has not been frozen. This is due to the cell membrane destruction at extremely low temperatures during freezing.

Lenticular cytoprotection. Part 1: the role of hypoxia inducible factors-1α and -2α and vascular endothelial growth factor in lens epithelial cell survival in hypoxia.

PubMed

Neelam, Sudha; Brooks, Morgan M; Cammarata, Patrick R

2013-01-01

The prosurvival signaling cascades that mediate the unique ability of human lens epithelial cells to survive in their naturally hypoxic environment are not well defined. Hypoxia induces the synthesis of the hypoxia inducible factor HIF-1α that in turn, plays a crucial role in modulating a downstream survival scheme, where vascular endothelial growth factor (VEGF) also plays a major role. To date, no published reports in the lens literature attest to the expression and functionality of HIF-2α and the role it might play in regulating VEGF expression. The aim of this study was to identify the functional expression of the hypoxia inducible factors HIF-1α and HIF-2α and establish their role in regulating VEGF expression. Furthermore, we demonstrate a link between sustained VEGF expression and the ability of the hypoxic human lens epithelial cell to thrive in low oxygen conditions and resist mitochondrial membrane permeability transition (also referred to as lenticular cytoprotection). Hypoxia inducible factor translation inhibitors were used to demonstrate the role of HIF-1α and HIF-2α and the simultaneous expression of both hypoxic inducible factors to determine their role in regulating VEGF expression. Axitinib, which inhibits lenticular cell autophosphorylation of its VEGF receptor, was employed to demonstrate a role for the VEGF-VEGFR2 receptor complex in regulating Bcl-2 expression. Specific antisera and western blot analysis were used to detect the protein levels of HIF-1α and HIF-2α, as well as the proapoptotic protein, BAX and the prosurvival protein, Bcl-2. VEGF levels were analyzed with enzyme-linked immunosorbent assay (ELISA). The potentiometric dye, 5,5',6,6'-tetrachloro1,1',3,3'-tetraethyl-benzimidazolylcarbocyanine iodide, was used to determine the effect of the inhibitors on mitochondrial membrane permeability transition. Cultured human lens epithelial cells (HLE-B3) maintained under hypoxic condition (1% oxygen) displayed consistent accumulation of VEGF throughout the 72 h incubation period. Using hypoxia inducible factor translation inhibitors targeting HIF-1α or HIF-2α, the specific inhibition of each protein did not diminish VEGF synthesis. The combined inhibition of HIF-1α and HIF-2α expression, using a double hypoxia inducible factor translation inhibitor, markedly decreased the level of VEGF. The inhibition of VEGF synthesis was associated with a profound deficiency in the level of the prosurvival protein, Bcl-2. Axitinib also prevented the VEGF-mediated expression of Bcl-2. The loss of VEGF coupled with the decrease in intracellular Bcl-2 correlated with marked mitochondrial depolarization, an early predictor of cellular apoptosis. Our data support a model in which the sustained synthesis of VEGF in human lens epithelial cells, maintained under hypoxic condition, is regulated by a compensatory inter-relationship between HIF-1α and HIF-2α. VEGF acts as a prosurvival factor in hypoxic lens epithelial cells by maintaining consistent expression of the prosurvival protein Bcl-2, which likely prevents the translocation of cytosolic BAX to the outer mitochondrial membrane, thus preventing the initiation of mitochondrial depolarization.

An Antagonistic Vascular Endothelial Growth Factor (VEGF) Variant Inhibits VEGF-Stimulated Receptor Autophosphorylation and Proliferation of Human Endothelial Cells

NASA Astrophysics Data System (ADS)

Siemeister, Gerhard; Schirner, Michael; Reusch, Petra; Barleon, Bernhard; Marme, Dieter; Martiny-Baron, Georg

1998-04-01

Vascular endothelial growth factor (VEGF) is a potent mitogen with a unique specificity for endothelial cells and a key mediator of aberrant endothelial cell proliferation and vascular permeability in a variety of human pathological situations, such as tumor angiogenesis, diabetic retinopathy, rheumatoid arthritis, or psoriasis. VEGF is a symmetric homodimeric molecule with two receptor binding interfaces lying on each pole of the molecule. Herein we report on the construction and recombinant expression of an asymmetric heterodimeric VEGF variant with an intact receptor binding interface at one pole and a mutant receptor binding interface at the second pole of the dimer. This VEGF variant binds to VEGF receptors but fails to induce receptor activation. In competition experiments, the heterodimeric VEGF variant antagonizes VEGF-stimulated receptor autophosphorylation and proliferation of endothelial cells. A 15-fold excess of the heterodimer was sufficient to inhibit VEGF-stimulated endothelial cell proliferation by 50%, and a 100-fold excess resulted in an almost complete inhibition. By using a rational approach that is based on the structure of VEGF, we have shown the feasibility to construct a VEGF variant that acts as an VEGF antagonist.

The Regulation of Vascular Endothelial Growth Factor by Hypoxia and Prostaglandin F2α during Human Endometrial Repair

PubMed Central

Maybin, Jacqueline A.; Hirani, Nikhil; Brown, Pamela; Jabbour, Henry N.

2011-01-01

Context: The human endometrium has an exceptional capacity for repeated repair after menses, but its regulation remains undefined. Premenstrually, progesterone levels fall and prostaglandin (PG) F2α synthesis increases, causing spiral arteriole constriction. We hypothesized that progesterone withdrawal, PGF2α, and hypoxia increase vascular endothelial growth factor (VEGF), an endometrial repair factor. Design and Results: Endometrial biopsies were collected (n = 47) with ethical approval and consent. VEGF mRNA, quantified by quantitative RT-PCR, was increased during menstruation (P < 0.01).VEGF protein was maximally secreted from proliferative endometrial explants. Treatment of an endometrial epithelial cell line and primary human endometrial stromal cells with 100 nm PGF2α or hypoxia (0.5% O2) resulted in significant increases in VEGF mRNA and protein. VEGF was maximal when cells were cotreated with PGF2α and hypoxia simultaneously (P < 0.05–0.001). Secretory-phase endometrial explants also showed an increase in VEGF with cotreatment (P < 0.05). However, proliferative-phase explants showed no increase in VEGF on treatment with PGF2α and/or hypoxia. Proliferative tissue was induced to increase VEGF mRNA expression when exposed to progesterone and its withdrawal in vitro but only in the presence of hypoxia and PG. Hypoxia-inducible factor-1α (HIF-1α) silencing with RNA interference suppressed hypoxia-induced VEGF expression in endometrial cells but did not alter PGF2α-induced VEGF expression. Conclusions: Endometrial VEGF is increased at the time of endometrial repair. Progesterone withdrawal, PGF2α, and hypoxia are necessary for this perimenstrual VEGF expression. Hypoxia acts via HIF-1α to increase VEGF, whereas PGF2α acts in a HIF-1α-independent manner. Hence, two pathways regulate the expression of VEGF during endometrial repair. PMID:21677035

PLACENTAL GROWTH FACTOR ADMINISTRATION ABOLISHES PLACENTAL ISCHEMIA-INDUCED HYPERTENSION

PubMed Central

Spradley, Frank T.; Tan, Adelene Y.; Joo, Woo S.; Daniels, Garrett; Kussie, Paul; Karumanchi, S. Ananth; Granger, Joey P.

2016-01-01

Preeclampsia is a pregnancy-specific disorder of new-onset hypertension. Unfortunately, the most effective treatment is early delivery of the fetus and placenta. Placental ischemia appears central to the pathogenesis of preeclampsia as placental ischemia/hypoxia induced in animals by reduced uterine perfusion pressure (RUPP) or in humans stimulates release of hypertensive placental factors into the maternal circulation. The anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1), which antagonizes and reduces bioavailable vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), is elevated in RUPP rats and preeclampsia. Although PlGF and VEGF are both natural ligands for sFlt-1, VEGF also has high affinity to VEGFR2 (Flk-1) causing side effects like edema. PlGF is specific for sFlt-1. We tested the hypothesis that PlGF treatment reduces placental ischemia-induced hypertension by antagonizing sFlt-1 without adverse consequences to the mother or fetus. On gestational day 14, rats were randomized to four groups: normal pregnant (NP) or RUPP ± infusion of rhPlGF (180 μg/kg/day; AG31, a purified, recombinant human form of PlGF) for 5 days via intraperitoneal osmotic minipumps. On day 19, mean arterial blood pressure and plasma sFlt-1 were higher and glomerular filtration rate lower in RUPP than NP rats. Infusion of rhPlGF abolished these changes seen with RUPP along with reducing oxidative stress. These data indicate that the increased sFlt-1 and reduced PlGF resulting from placental ischemia contribute to maternal hypertension. Our novel finding that rhPlGF abolishes placental ischemia-induced hypertension, without major adverse consequences, suggests a strong therapeutic potential for this growth factor in preeclampsia. PMID:26831193

Effect of human vascular endothelial growth factor gene transfer on endogenous vascular endothelial growth factor mRNA expression in a rat fibroblast and osteoblast culture model.

PubMed

Li, Ru; Li, Claire H; Nauth, Aaron; McKee, Michael D; Schemitsch, Emil H

2010-09-01

Vascular endothelial growth factor (VEGF) plays an important role in promoting angiogenesis and osteogenesis during fracture repair. Our previous studies have shown that cell-based VEGF gene therapy enhances bone healing of a rabbit tibia segmental bone defect in vivo. The aim of this project was to examine the effect of exogenous human VEGF on the endogenous rat VEGF messenger RNA (mRNA) expression in a cell-based gene transfer model. Rat fibroblasts and osteoblasts were harvested from the dermal tissue and periosteum, respectively, of Fisher 344 rats. The cells were then cultured and transfected with pcDNA-human VEGF using Superfect reagent (Qiagen). Four experimental groups were created: 1) fibroblast-VEGF; 2) osteoblast-VEGF; 3) nontransfected fibroblast controls; and 4) nontransfected osteoblast controls. The cultured cells were harvested at 1, 3, and 7 days after the gene transfection. The total mRNA was extracted (Trizol; Invitrogen); both human VEGF and rat VEGF mRNA were measured by reverse transcriptase-polymerase chain reaction and quantified by VisionWorksLS. The human VEGF165 mRNA was detected by reverse transcriptase-polymerase chain reaction from transfected fibroblasts and osteoblasts at 1, 3, and 7 days after gene transfection. The human VEGF165 levels peaked at Day 1 and then gradually reduced expression in both transfected fibroblasts and osteoblasts. Two endogenous rat VEGF isoforms were detected in this cell culture model: rat VEGF120 and rat VEGF164. We compared the rat VEGF120 and rat VEGF164 expression level of the fibroblasts or osteoblasts that were transfected with human VEGF165, with nontransfected control cells. Both the transfected fibroblasts and osteoblasts showed greater expression of rat VEGF164 than nontransfected controls at Day 1 (peak level) and Day 3, but not at Day 7. The expression of rat VEGF120 was lower in transfected fibroblasts, but higher in transfected osteoblasts, than the relevant control groups at any time point after transfection. In addition, human VEGF gene transfection increased osteoblast cell proliferation after 3 days. These in vitro results suggest that cell-based human VEGF gene therapy is not only effective at causing human VEGF expression, but also enhances endogenous rat VEGF mRNA expression in both fibroblasts and osteoblasts, particularly the rat VEGF164 isoform.

Helicobacter pylori induces vascular endothelial growth factor production in gastric epithelial cells through hypoxia-inducible factor-1α-dependent pathway.

PubMed

Kang, Min-Jung; Song, Eun-Jung; Kim, Bo-Yeon; Kim, Dong-Jae; Park, Jong-Hwan

2014-12-01

Although Helicobacter pylori have been known to induce vascular endothelial growth factor (VEGF) production in gastric epithelial cells, the precise mechanism for cellular signaling is incompletely understood. In this study, we investigated the role of bacterial virulence factor and host cellular signaling in VEGF production of H. pylori-infected gastric epithelial cells. We evaluated production of VEGF, activation of nuclear factor nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPKs) and hypoxia-inducible factor-1α (HIF-1α) stabilization in gastric epithelial cells infected with H. pylori WT or isogenic mutants deficient in type IV secretion system (T4SS). H. pylori induced VEGF production in gastric epithelial cells via both T4SS-dependent and T4SS-independent pathways, although T4SS-independent pathway seems to be the dominant signaling. The inhibitor assay implicated that activation of NF-κB and MAPKs is dispensable for H. pylori-induced VEGF production in gastric epithelial cells. H. pylori led to HIF-1α stabilization in gastric epithelial cells independently of T4SS, NF-κB, and MAPKs, which was essential for VEGF production in these cells. N-acetyl-cysteine (NAC), a reactive oxygen species (ROS) inhibitor, treatment impaired H. pylori-induced HIF-1α stabilization and VEGF production in gastric epithelial cells. We defined the important role of ROS-HIF-1α axis in VEGF production of H. pylori-infected gastric epithelial cells, and bacterial T4SS has a minor role in H. pylori-induced VEGF production of gastric epithelial cells. © 2014 John Wiley & Sons Ltd.

VEGF111b, a new member of VEGFxxxb isoforms and induced by mitomycin C, inhibits angiogenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gu, Fang; Li, Xiuli; Kong, Jian

2013-11-08

Highlights: •We discovered a new member of VEGFxxxb family-VEGF111b. •We found VEGF111b mRNA and protein can be induced by mitomycin C. •We confirmed VEGF111b over-expression inhibits angiogenesis. •VEGF111b inhibits angiogenesis through inhibiting VEGF-R2/PI3K/Akt and VEGF-R2/ERK1/2 phosphorylation. -- Abstract: Vascular endothelial growth factor (VEGF-A) stimulating angiogenesis is required for tumor growth and progression. The conventional VEGF-A isoforms have been considered as pro-angiogenic factors. Another family of VEGF-A isoforms generated by alternative splicing, termed VEGFxxxb isoforms, has anti-angiogenic property, exemplified by VEGF165b. Here, we identify a new number of VEGFxxx family-VEGF111b induced by mitomycin C, although not detected in mitomycin C-unexposed ovarianmore » cancer cells. SKOV3 cells were transfected with pcDNA{sub 3.1} empty vector, pcDNA{sub 3.1}-VEGF111b or pcDNA{sub 3.1}-VEGF165b to collect conditioned mediums respectively. VEGF111b overexpression inhibits proliferation, migration and tube formation of endothelial cell by inhibiting VEGF-R2 phosphorylation and its downstream signaling, similar to VEGF165b but slightly lower than VEGF165b. The anti-angiogenic property depends on the six amino acids of exon 8b of the VEGFxxxb isoforms. Our results show that VEGF111b is a novel potent anti-angiogenic agent that can target the VEGF-R2 and its signaling pathway to inhibit ovarian tumor growth.« less

Role of EG-VEGF in human placentation: Physiological and pathological implications.

PubMed

Hoffmann, Pascale; Saoudi, Yasmina; Benharouga, Mohamed; Graham, Charles H; Schaal, Jean-Patrick; Mazouni, Chafika; Feige, Jean-Jacques; Alfaidy, Nadia

2009-08-01

Pre-eclampsia (PE), the major cause of maternal morbidity and mortality, is thought to be caused by shallow invasion of the maternal decidua by extravillous trophoblasts (EVT). Data suggest that a fine balance between the expressions of pro- and anti-invasive factors might regulate EVT invasiveness. Recently, we showed that the expression of the new growth factor endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is high in early pregnancy but falls after 11 weeks, suggesting an essential role for this factor in early pregnancy. Using human villous explants and HTR-8/SVneo, a first trimester extravillous trophoblast cell line, we showed differential expression of EG-VEGF receptors, PKR1 and PKR2, in the placenta and demonstrated that EG-VEGF inhibits EVT migration, invasion and tube-like organisation. EG-VEGF inhibitory effect on invasion was supported by a decrease in matrix metalloproteinase (MMP)-2 and MMP-9 production. Interference with PKR2 expression, using specific siRNAs, reversed the EG-VEGF-induced inhibitory effects. Furthermore, we determined EG-VEGF circulating levels in normal and PE patients. Our results showed that EG-VEGF levels were highest during the first trimester of pregnancy and decreased thereafter to non-pregnant levels. More important, EG-VEGF levels were significantly elevated in PE patients compared with age-matched controls. These findings identify EG-VEGF as a novel paracrine regulator of trophoblast invasion. We speculate that a failure to correctly down-regulate placental expression of EG-VEGF at the end of the first trimester of pregnancy might lead to PE.

The Related Transcriptional Enhancer Factor-1 Isoform, TEAD4216, Can Repress Vascular Endothelial Growth Factor Expression in Mammalian Cells

PubMed Central

Appukuttan, Binoy; McFarland, Trevor J.; Stempel, Andrew; Kassem, Jean B.; Hartzell, Matthew; Zhang, Yi; Bond, Derek; West, Kelsey; Wilson, Reid; Stout, Andrew; Pan, Yuzhen; Ilias, Hoda; Robertson, Kathryn; Klein, Michael L.; Wilson, David; Smith, Justine R.; Stout, J. Timothy

2012-01-01

Increased cellular production of vascular endothelial growth factor (VEGF) is responsible for the development and progression of multiple cancers and other neovascular conditions, and therapies targeting post-translational VEGF products are used in the treatment of these diseases. Development of methods to control and modify the transcription of the VEGF gene is an alternative approach that may have therapeutic potential. We have previously shown that isoforms of the transcriptional enhancer factor 1-related (TEAD4) protein can enhance the production of VEGF. In this study we describe a new TEAD4 isoform, TEAD4216, which represses VEGF promoter activity. The TEAD4216 isoform inhibits human VEGF promoter activity and does not require the presence of the hypoxia responsive element (HRE), which is the sequence critical to hypoxia inducible factor (HIF)-mediated effects. The TEAD4216 protein is localized to the cytoplasm, whereas the enhancer isoforms are found within the nucleus. The TEAD4216 isoform can competitively repress the stimulatory activity of the TEAD4434 and TEAD4148 enhancers. Synthesis of the native VEGF165 protein and cellular proliferation is suppressed by the TEAD4216 isoform. Mutational analysis indicates that nuclear or cytoplasmic localization of any isoform determines whether it acts as an enhancer or repressor, respectively. The TEAD4216 isoform appears to inhibit VEGF production independently of the HRE required activity by HIF, suggesting that this alternatively spliced isoform of TEAD4 may provide a novel approach to treat VEGF-dependent diseases. PMID:22761647

A novel model of persistent retinal neovascularization for the development of sustained anti-VEGF therapies.

PubMed

Li, Yong; Busoy, Joanna Marie; Zaman, Ben Alfyan Achirn; Tan, Queenie Shu Woon; Tan, Gavin Siew Wei; Barathi, Veluchamy Amutha; Cheung, Ning; Wei, Jay Ji-Ye; Hunziker, Walter; Hong, Wanjin; Wong, Tien Yin; Cheung, Chui Ming Gemmy

2018-05-28

Anti-vascular endothelial growth factor (VEGF) therapies lead to a major breakthrough in treatment of neovascular retinal diseases such as age-related macular degeneration or diabetic retinopathy. Current management of these conditions require regular and frequent intravitreal injections to prevent disease recurrence once the effect of the injected drug wears off. This has led to a pressing clinical need of developing sustained release formulations or therapies with longer duration. A major drawback in developing such therapies is that the currently available animal models show spontaneous regression of vascular leakage. They therefore not only fail to recapitulate retinal vascular disease in humans, but also prevent to discern if regression is due to prolonged therapeutic effect or simply reflects spontaneous healing. Here, we described the development of a novel rabbit model of persistent retinal neovascularization (PRNV). Retinal Müller glial are essential for maintaining the integrity of the blood-retinal barrier. Intravitreal injection of DL-alpha-aminoadipic acid (DL-AAA), a selective retinal glial (Müller) cell toxin, results in persistent vascular leakage for up to 48 weeks. We demonstrated that VEGF concentrations were significantly increased in vitreous suggesting VEGF plays a significant role in mediating the leakage observed. Intravitreal administration of anti-VEGF drugs (e.g. bevacizumab, ranibizumab and aflibercept) suppresses vascular leakage for 8-10 weeks, before recurrence of leakage to pre-treatment levels. All three anti-VEGF drugs are very effective in re-ducing angiographic leakage in PRNV model, and aflibercept demonstrated a longer duration of action compared with the others, reminiscent of what is observed with these drugs in human in the clinical setting. Therefore, this model provides a unique tool to evaluate novel anti-VEGF formulations and therapies with respect to their duration of action in comparison to the currently used drugs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) and its receptor PROKR2 are associated to human colorectal cancer progression and peritoneal carcinomatosis.

PubMed

Benlahfid, Mohammed; Traboulsi, Wael; Sergent, Frederic; Benharouga, Mohamed; Elhattabi, Khalid; Erguibi, Driss; Karkouri, Mehdi; Elattar, Hicham; Fadil, Abdelaziz; Fahmi, Yassine; Aboussaouira, Touria; Alfaidy, Nadia

2018-02-06

The highest risk factor for mortality among malignant tumors is metastasis. Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an angiogenic factor which biological activity is mediated via two G protein-coupled receptors, prokineticin receptor1 (PROKR1) and PROKR2. Recent studies suggested that EG-VEGF expression is deregulated in multiple cancers including colorectal cancer (CRC). Using distinctive CRC and peritoneal carcinomatosis (PC) cohorts and a corresponding control cohort, we determined the circulating levels of EG-VEGF and its in situ expression, and that of its related receptors. Circulating EG-VEGF levels were significantly increased in patients with metastatic PC compared to CRC and control patients (p< 0.05). Furthermore, according to clinicopathologic examinations, local EG-VEGF expression correlated with higher tumor and nodal stages (p< 0.001) of CRC. EG-VEGF and PROKR2 were highly expressed in colorectal primary lesions compared to positive controls. PROKR1 expression was lower and did not change in tumor specimens. Also, EG-VEGF and its receptor PROKR2 were differentially expressed in the colorectal primary lesions and in the control groups. Altogether these findings suggest that EG-VEGF/receptors system might be an important actor in the CRC progression into PC and might be involved in the ability of tumor cells to invade other organs. Circulating EG-VEGF could be proposed as a prognostic marker in human CRC and its progression into PC.

Revealing the role of phospholipase Cβ3 in the regulation of VEGF-induced vascular permeability

PubMed Central

Hoeppner, Luke H.; Phoenix, Kathryn N.; Clark, Karl J.; Bhattacharya, Resham; Gong, Xun; Sciuto, Tracey E.; Vohra, Pawan; Suresh, Sandip; Bhattacharya, Santanu; Dvorak, Ann M.; Ekker, Stephen C.; Dvorak, Harold F.; Claffey, Kevin P.

2012-01-01

VEGF induces vascular permeability (VP) in ischemic diseases and cancer, leading to many pathophysiological consequences. The molecular mechanisms by which VEGF acts to induce hyperpermeability are poorly understood and in vivo models that easily facilitate real-time, genetic studies of VP do not exist. In the present study, we report a heat-inducible VEGF transgenic zebrafish (Danio rerio) model through which VP can be monitored in real time. Using this approach with morpholino-mediated gene knock-down and knockout mice, we describe a novel role of phospholipase Cβ3 as a negative regulator of VEGF-mediated VP by regulating intracellular Ca2+ release. Our results suggest an important effect of PLCβ3 on VP and provide a new model with which to identify genetic regulators of VP crucial to several disease processes. PMID:22674805

Restraint of angiogenesis by zinc finger transcription factor CTCF-dependent chromatin insulation

PubMed Central

Tang, Ming; Chen, Bo; Pardo, Carolina; Pampo, Christine; Chen, Jing; Lien, Ching-Ling; Wu, Lizi; Wang, Heiman; Yao, Kai; Oh, S. Paul; Seto, Edward; Smith, Lois E. H.; Siemann, Dietmar W.; Kladde, Michael P.; Cepko, Constance L.; Lu, Jianrong

2011-01-01

Angiogenesis is meticulously controlled by a fine balance between positive and negative regulatory activities. Vascular endothelial growth factor (VEGF) is a predominant angiogenic factor and its dosage is precisely regulated during normal vascular formation. In cancer, VEGF is commonly overproduced, resulting in abnormal neovascularization. VEGF is induced in response to various stimuli including hypoxia; however, very little is known about the mechanisms that confine its induction to ensure proper angiogenesis. Chromatin insulation is a key transcription mechanism that prevents promiscuous gene activation by interfering with the action of enhancers. Here we show that the chromatin insulator-binding factor CTCF binds to the proximal promoter of VEGF. Consistent with the enhancer-blocking mode of chromatin insulators, CTCF has little effect on basal expression of VEGF but specifically affects its activation by enhancers. CTCF knockdown cells are sensitized for induction of VEGF and exhibit elevated proangiogenic potential. Cancer-derived CTCF missense mutants are mostly defective in blocking enhancers at the VEGF locus. Moreover, during mouse retinal development, depletion of CTCF causes excess angiogenesis. Therefore, CTCF-mediated chromatin insulation acts as a crucial safeguard against hyperactivation of angiogenesis. PMID:21896759

Immunoexpression of vascular endothelial growth factor in periapical granulomas, radicular cysts, and residual radicular cysts.

PubMed

Nonaka, Cassiano Francisco Weege; Maia, Alexandre Pinto; Nascimento, George João Ferreira do; de Almeida Freitas, Roseana; Batista de Souza, Lélia; Galvão, Hébel Cavalcanti

2008-12-01

Our aim was to assess and compare the immunoexpression of vascular endothelial growth factor (VEGF) in periapical granulomas (PGs), radicular cysts (RCs), and residual radicular cysts (RRCs), relating it to the angiogenic index and the intensity of the inflammatory infiltrate. Twenty PGs, 20 RCs, and 10 RRCs were evaluated by immunohistochemistry using anti-VEGF antibody. Angiogenic index was determined by microvessel count (MVC) using anti-von Willebrand factor antibody. The PGs and RCs showed higher expression of VEGF than the RRCs. Lesions presenting few inflammatory infiltrate revealed the lowest immunoexpression of VEGF (P < .05). Irrespective of the intensity of the inflammatory infiltrate, most of the RCs and RRCs showed moderate to strong epithelial expression of VEGF. Lesions showing dense inflammatory infiltrate presented higher MVC indices (P < .05). VEGF expression and MVC did not reveal a significant correlation (P > .05). VEGF is present in periapical inflammatory lesions but at a lower level in RRCs. The expression of this proangiogenic factor is closely related to the intensity of the inflammatory infiltrate in these lesions.

The roles of vascular endothelial growth factor in bone repair and regeneration

PubMed Central

Hu, Kai; Olsen, Bjorn R.

2016-01-01

Vascular endothelial growth factor-A (VEGF) is one of the most important growth factors for regulation of vascular development and angiogenesis. Since bone is a highly vascularized organ and angiogenesis plays an important role in osteogenesis, VEGF also influences skeletal development and postnatal bone repair. Compromised bone repair and regeneration in many patients can be attributed to impaired blood supply; thus, modulation of VEGF levels in bones represents a potential strategy for treating compromised bone repair and improving bone regeneration. This review (i) summarizes the roles of VEGF at different stages of bone repair, including the phases of inflammation, endochondral ossification, intramembranous ossification during callus formation and bone remodeling; (ii) discusses different mechanisms underlying the effects of VEGF on osteoblast function, including paracrine, autocrine and intracrine signaling during bone repair; (iii) summarizes the role of VEGF in the bone regenerative procedure, distraction osteogenesis; and (iv) reviews evidence for the effects of VEGF in the context of repair and regeneration techniques involving the use of scaffolds, skeletal stem cells and growth factors. PMID:27353702

Hematological and hepatic effects of vascular epidermal growth factor (VEGF) used to stimulate hair growth in an animal model.

PubMed

Gnann, Laís Angelo; Castro, Rafael Ferreira; Azzalis, Ligia Ajaime; Feder, David; Perazzo, Fabio Ferreira; Pereira, Edimar Cristiano; Rosa, Paulo César Pires; Junqueira, Virginia Berlanga Campos; Rocha, Katya Cristina; Machado, Carlos D' Aparecida; Paschoal, Francisco Camargo; de Abreu, Luiz Carlos; Valenti, Vitor Engrácia; Fonseca, Fernando Luiz Affonso

2013-10-29

Alopecia areata is the hair loss usually reversible, in sharply defined areas. The treatment of alopecia using growth factors shows interesting activity in promoting hair growth. In this concept, VEGF (vascular endothelial growth factor) is a marker of angiogenesis, stimulating hair growth by facilitating the supply of nutrients to the hair follicle, increasing follicular diameter. The aim of this study was the evaluation of a topical gel enriched with VEGF liposomes on the hair growth stimulation and its toxicological aspects. Mesocricetus auratus were randomly divided into three groups. Control group was treated with Aristoflex® gel, 1% group with the same gel but added 1% VEGF and 3% group with 3% VEGF. Biochemical, hematological and histological analyses were done. At the end of the experiment (15th day of VEGF treatment) efficacy was determined macroscopically by hair density dermatoscopy analysis, and microscopically by hair diameter analysis. They both demonstrated that hair of the VEGF group increased faster and thicker than control. On the other hand, biochemical and hematological results had shown that VEGF was not 100% inert. VEGF increased hair follicle area, but more studies are necessary to confirm its toxicity.

Vascular Endothelial Growth Factor Secretion by Nonmyocytes Modulates Connexin-43 Levels in Cardiac Organoids

PubMed Central

Iyer, Rohin K.; Odedra, Devang; Chiu, Loraine L.Y.; Vunjak-Novakovic, Gordana

2012-01-01

We previously showed that the sequential, but not simultaneous, culture of endothelial cells (ECs), fibroblasts (FBs), and cardiomyocytes (CMs) resulted in elongated, beating cardiac organoids. We hypothesized that the expression of Cx43 and contractile function are mediated by vascular endothelial growth factor (VEGF) released by nonmyocytes during the preculture period. Cardiac organoids (∼200 μm diameter) were cultivated in microchannels to enable rapid screening. Three experimental groups were formed: (i) Simultaneous Preculture (ECs+FBs for 48 h, followed by CMs), (ii) Sequential Preculture (ECs for 24 h, FBs for 24 h, followed by CMs), and (iii) Simultaneous Triculture (ECs+FBs+CMs). Controls included CMs only, FBs only, and ECs only groups, and preculture with ECs only or FBs only. The highest VEGF levels were found in the Preculture groups [Simultaneous Preculture, 8.9±2.7 ng/(mL·h−1); Sequential Preculture, 16.6±3.4 ng/(mL·h−1)], as compared with Simultaneous Triculture where VEGF was not detectable, as shown by enzyme-linked immunosorbent assay. Analytical flow cytometry showed that VEGFR2 was expressed by ECs (86%±2 VEGFR2+), FBs (44%±1 VEGFR2+), and CMs (49%±2 VEGFR2+), showing that all three cell types were capable of responding to changes in VEGF. Addition of anti-VEGF neutralizing IgG (0.4 μg/mL) to Simultaneous Preculture resulted in 3-fold decrease in Cx43 mRNA and 1.5-fold decrease in Cx43 protein, while Simultaneous Triculture supplemented with VEGF ligand (30 ng/mL) had a threefold increase in Cx43 mRNA and a twofold increase in Cx43 protein. Addition of a small molecule inhibitor of the VEGFR2 receptor (19.4 nM) to Sequential Preculture caused a 1.4-fold decrease in Cx43 mRNA and a 4.1-fold decrease in Cx43 protein. Cx43 was localized within CMs, and not within FBs or ECs. Enriched CM organoids and Sequential Preculture organoids grown in the presence of VEGFR2 inhibitor displayed low levels of Cx43 and poor functional properties. Taken together, these results suggest that endogenous VEGF-VEGFR2 signaling enhanced Cx43 expression and cardiac function in engineered cardiac organoids. PMID:22519405

Placental expression of EG-VEGF and its receptors PKR1 (prokineticin receptor-1) and PKR2 throughout mouse gestation.

PubMed

Hoffmann, P; Feige, J-J; Alfaidy, N

2007-10-01

Compelling evidence indicates that vascular endothelial growth factor (VEGF) is an important mediator of placental angiogenesis and appears to be disregulated in pre-eclampsia (PE). Recently, we characterised the expression of EG-VEGF (endocrine gland-derived vascular endothelial growth factor), also known as prokineticin 1 (PK1) in human placenta during the first trimester of pregnancy and showed that this factor is likely to play an important role in human placentation. However, because it is impossible to prospectively study placentation in humans, it has been impossible to further characterise EG-VEGF expression throughout complete gestation and especially at critical gestational ages for PE development. In the present study, we used mouse placenta to further characterise EG-VEGF expression throughout gestation. We investigated the pattern of expression of EG-VEGF and its receptors, PKR1 and PKR2 at the mRNA and protein levels. Our results show that EG-VEGF and VEGF exhibit different patterns of expression and different localisations in the mouse placenta. EG-VEGF was mainly localised in the labyrinth whereas VEGF was mainly present in glycogen and giant cells. EG-VEGF mRNA and protein levels were highest before 10.5days post coitus (dpc) whereas those of VEGF showed stable expression throughout gestation. PKR1 protein was localised to the labyrinth layer and showed the same pattern of expression as EG-VEGF whereas PKR2 expression was maintained over 10.5dpc with both trophoblastic and endothelial cell localisations. Altogether these findings suggest that EG-VEGF may have a direct effect on both endothelial and trophoblastic cells and is likely to play an important role in mouse placentation.

The cellular response to vascular endothelial growth factors requires co-ordinated signal transduction, trafficking and proteolysis

PubMed Central

Smith, Gina A.; Fearnley, Gareth W.; Tomlinson, Darren C.; Harrison, Michael A.; Ponnambalam, Sreenivasan

2015-01-01

VEGFs (vascular endothelial growth factors) are a family of conserved disulfide-linked soluble secretory glycoproteins found in higher eukaryotes. VEGFs mediate a wide range of responses in different tissues including metabolic homoeostasis, cell proliferation, migration and tubulogenesis. Such responses are initiated by VEGF binding to soluble and membrane-bound VEGFRs (VEGF receptor tyrosine kinases) and co-receptors. VEGF and receptor splice isoform diversity further enhances complexity of membrane protein assembly and function in signal transduction pathways that control multiple cellular responses. Different signal transduction pathways are simultaneously activated by VEGFR–VEGF complexes with membrane trafficking along the endosome–lysosome network further modulating signal output from multiple enzymatic events associated with such pathways. Balancing VEGFR–VEGF signal transduction with trafficking and proteolysis is essential in controlling the intensity and duration of different intracellular signalling events. Dysfunction in VEGF-regulated signal transduction is important in chronic disease states including cancer, atherosclerosis and blindness. This family of growth factors and receptors is an important model system for understanding human disease pathology and developing new therapeutics for treating such ailments. PMID:26285805

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is released by female mouse bladder urothelial cells and expressed by the urothelium as an early response to lipopolysaccharides (LPS).

PubMed

Li, Yan; Lu, Ming; Alvarez-Lugo, Lery; Chen, Gang; Chai, Toby C

2017-04-01

We studied in vitro and in vivo response of primary mouse bladder urothelial cells (mBUC) and bladder urothelium to lipopolysaccharides (LPS), focusing on granulocyte-macrophage colony-stimulating factor (GM-CSF) signaling. Female C57BL/6 mBUC were exposed for 12 hr to differing concentrations of LPS (100 ng/ml to 10 µg/ml). mBUC were also exposed to a single dose of LPS (1 µg/ml) for 3, 6, 12 hr. Neutralizing GM-CSF antibody (0.1 μg/ml) was used block GM-CSF activity in vitro. In vivo experiments were performed, whereby, LPS (1 mg/ml) was instilled intravesically and left to dwell for 30 min followed by harvest of bladder urothelium 3 to 18 hr later. ELISA measured GM-CSF. qPCR quantitated mRNA for GM-CSF, vascular endothelial growth factor-A (VEGF-A), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and tumor necrosis factor α (TNF-α). RT-PCR was used to detect mRNA for GM-CSF, GM-CSFRα, and β in bladder tissues. Immunohistofluorescence and Western blots for GM-CSFRα were performed on bladder tissues. LPS induced a dose-dependent release of GM-CSF by mBUC. Mouse bladder urothelium did not express GM-CSF mRNA at baseline, but expressed GM-CSF mRNA 3 hr after in vivo LPS exposure, with GM-CSF mRNA expression disappearing 18 hr later. GM-CSFRα expression was confirmed in bladder urothelium. GM-CSF neutralizing antibody significantly diminished LPS-induced increases of VEGF and COX-2 mRNA expression. Urothelium and mBUC secreted GM-CSF as an early response to LPS. GM-CSF mediated downstream expression of VEGF and COX-2. Urothelial GM-CSF may function as a signaling mediator for both inflammation and pain transduction. Neurourol. Urodynam. 36:1020-1025, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Differential regulation of ANG2 and VEGF-A in human granulosa lutein cells by choriogonadotropin.

PubMed

Pietrowski, D; Keck, C

2004-04-01

The growth and development of the corpus luteum after rupture of the follicle is a highly regulated process characterised by a rapid vascularization of the follicle surrounding granulosa cells. Vascularization is regulated by a large number of growth factors and cytokines whereas members of the angiopoietin family and VEGF-A are reported to play a principal role. The gonadotropic hormones luteinizing hormone and choriogonadotropin are reported to be essential for corpus luteum formation. In this study we investigated by RT PCR if the growth factors PGF, PDGF-A, PDGF-B, VEGF-A, VEGF-B, VEGF-C, VEGF-D, ANG1, ANG2, ANG3 and ANG4 are expressed in granulosa cells. We show the expression of VEGF-A, VEGF-B, PDGF-A, ANG1 and ANG2 in granulosa cells. Using RT-PCR and Real-Time PCR we demonstrate that angiopoietin 2 is downregulated in human granulosa cells in vitro after choriogonadotropin treatment whereas the expression of angiopoietin 1 is not significantly altered. The expression of VEGF on the RNA- and on the protein level was determined. It was shown that in granulosa cells VEGF is upregulated after choriogonadotropin treatment on the RNA level and that increasing concentrations of choriogonadotropin from 0 to 10 U/ml leads to an increasing amount of VEGF in the cell culture supernatants. The amount of VEGF in the supernatants reaches a plateau at 0.5 U/ml and is increased only slightly and not significantly after treatment of the cells with 10 U/ml choriogonadotropin compared to 0.5 U/ml. In total these findings suggests that in granulosa cells the mRNA of various growth factors is detectable by RT-PCR and that VEGF-A and ANG2 is regulated by the gonadotropic hormone choriogonadotropin. These findings may add impact on the hypothesis of choriogonadotropin as a novel angiogenic factor.

Leakage-resistant blood vessels in mice transgenically overexpressing angiopoietin-1.

PubMed

Thurston, G; Suri, C; Smith, K; McClain, J; Sato, T N; Yancopoulos, G D; McDonald, D M

1999-12-24

Angiopoietin-1 (Ang1) and vascular endothelial growth factor (VEGF) are endothelial cell-specific growth factors. Direct comparison of transgenic mice overexpressing these factors in the skin revealed that the VEGF-induced blood vessels were leaky, whereas those induced by Ang1 were nonleaky. Moreover, vessels in Ang1-overexpressing mice were resistant to leaks caused by inflammatory agents. Coexpression of Ang1 and VEGF had an additive effect on angiogenesis but resulted in leakage-resistant vessels typical of Ang1. Ang1 therefore may be useful for reducing microvascular leakage in diseases in which the leakage results from chronic inflammation or elevated VEGF and, in combination with VEGF, for promoting growth of nonleaky vessels.

Causation by Diesel Exhaust Particles of Endothelial Dysfunctions in Cytotoxicity, Pro-inflammation, Permeability, and Apoptosis Induced by ROS Generation.

PubMed

Tseng, Chia-Yi; Wang, Jhih-Syuan; Chao, Ming-Wei

2017-10-01

Epidemiological studies suggest that an increase of diesel exhaust particles (DEP) in ambient air corresponds to an increase in hospital-recorded myocardial infarctions within 48 h after exposure. Among the many theories to explain this data are endothelial dysfunction and translocation of DEP into vasculature. The mechanisms for such DEP-induced vascular permeability remain unknown. One of the major mechanisms underlying the effects of DEP is suggested to be oxidative stress. Experiments have shown that DEP induce the generation of reactive oxygen species (ROS), such as superoxide anion and H 2 O 2 in the HUVEC tube cells. Transcription factor Nrf2 is translocated to the cell nucleus, where it activates transcription of the antioxidative enzyme HO-1 and sequentially induces the release of vascular permeability factor VEGF-A. Furthermore, a recent study shows that DEP-induced intracellular ROS may cause the release of pro-inflammatory TNF-α and IL-6, which may induce endothelial permeability as well by promoting VEGF-A secretion independently of HO-1 activation. These results demonstrated that the adherens junction molecule, VE-cadherin, becomes redistributed from the membrane at cell-cell borders to the cytoplasm in response to DEP, separating the plasma membranes of adjacent cells. DEP were occasionally found in endothelial cell cytoplasm and in tube lumen. In addition, the induced ROS is cytotoxic to the endothelial tube-like HUVEC. Acute DEP exposure stimulates ATP depletion, followed by depolarization of their actin cytoskeleton, which sequentially inhibits PI3K/Akt activity and induces endothelial apoptosis. Nevertheless, high-dose DEP augments tube cell apoptosis up to 70 % but disrupts the p53 negative regulator Mdm2. In summary, exposure to DEP affects parameters influencing vasculature permeability and viability, i.e., oxidative stress and its upregulated antioxidative and pro-inflammatory responses, which sequentially induce vascular permeability factor, VEGF-A release and disrupt cell-cell junction integrity. While exposure to a low dose of DEP actin triggers cytoskeleton depolarization, reduces PI3K/Akt activity, and induces a p53/Mdm2 feedback loop, a high dose causes apoptosis by depleting Mdm2. Addition of ROS scavenger N-acetyl cysteine suppresses DEP-induced oxidative stress efficiently and reduces subsequent damages by increasing endogenous glutathione.

VEGF-incorporated biomimetic poly(lactide-co-glycolide) sintered microsphere scaffolds for bone tissue engineering.

PubMed

Jabbarzadeh, Ehsan; Deng, Meng; Lv, Qing; Jiang, Tao; Khan, Yusuf M; Nair, Lakshmi S; Laurencin, Cato T

2012-11-01

Regenerative engineering approaches utilizing biomimetic synthetic scaffolds provide alternative strategies to repair and restore damaged bone. The efficacy of the scaffolds for functional bone regeneration critically depends on their ability to induce and support vascular infiltration. In the present study, three-dimensional (3D) biomimetic poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds were developed by sintering together PLAGA microspheres followed by nucleation of minerals in a simulated body fluid. Further, the angiogenic potential of vascular endothelial growth factor (VEGF)-incorporated mineralized PLAGA scaffolds were examined by monitoring the growth and phenotypic expression of endothelial cells on scaffolds. Scanning electron microscopy micrographs confirmed the growth of bone-like mineral layers on the surface of microspheres. The mineralized PLAGA scaffolds possessed interconnectivity and a compressive modulus of 402 ± 61 MPa and compressive strength of 14.6 ± 2.9 MPa. Mineralized scaffolds supported the attachment and growth and normal phenotypic expression of endothelial cells. Further, precipitation of apatite layer on PLAGA scaffolds resulted in an enhanced VEGF adsorption and prolonged release compared to nonmineralized PLAGA and, thus, a significant increase in endothelial cell proliferation. Together, these results demonstrated the potential of VEGF-incorporated biomimetic PLAGA sintered microsphere scaffolds for bone tissue engineering as they possess the combined effects of osteointegrativity and angiogenesis. Copyright © 2012 Wiley Periodicals, Inc.

Antisense oligodeoxynucleotide inhibits vascular endothelial growth factor expression in U937 foam cells.

PubMed

Yang, Peng-Yuan; Rui, Yao-Cheng; Jin, You-Xin; Li, Tie-Jun; Qiu, Yan; Zhang, Li; Wang, Jie-Song

2003-06-01

To study the expression of vascular endothelial growth factor (VEGF) induced by oxidized low density liporotein (ox-LDL) and the inhibitory effects of antisense oligodeoxynucleotide (asODN) on the levels of VEGF protein and mRNA in the U937 foam cells. U937 cells were incubated with ox-LDL 80 mg/L for 48 h, then, the foam cells were treated with asODN (0, 5, 10, and 20 micromol/L). The VEGF concentration in the media was determined by ELISA. The VEGF protein expression level in cells was measured by immuohistochemistry; the positive ratio detected by a morphometrical analysis system was used as the amount of the VEGF expression level. The VEGF mRNA level was examined by Northern blotting. After U937 cells were incubated with ox-LDL, VEGF expression level increased greatly both in the cells and in the media. asODN markedly inhibited the increase of VEGF. After treatment with asODN 20 micromol/L, the VEGF protein concentration in the media decreased by 45.0%, the VEGF positive ratio detected by immuohistochemistry in cells decreased by 64.9%, and the VEGF mRNA level decreased by 47.1%. The expression of VEGF in U937 foam cells was strong. asODN inhibited VEGF expression significantly in U937 foam cells in vitro.

Immunohistochemical expression of vascular endothelial growth factor in canine oral squamous cell carcinomas.

PubMed

Martano, Manuela; Restucci, Brunella; Ceccarelli, Dora Maria; Lo Muzio, Lorenzo; Maiolino, Paola

2016-01-01

Angiogenesis is crucial for the growth and metastasis of malignant tumours, and various proangiogenic factors promote this process. One of these factors is vascular endothelial growth factor (VEGF), which appears to play a key role in tumour angiogenesis. The aim of the present study was to assess whether VEGF expression is associated with angiogenesis, disease progression and neoplastic proliferation in canine oral squamous cell carcinoma (OSCC) tissue. VEGF immunoreactivity was quantified by immunohistochemistry in 30 specimens, including normal oral mucosa and OSCC tissues graded as well, moderately or poorly differentiated. VEGF expression was correlated with tumour cell proliferation, as assessed using the proliferating cell nuclear antigen (PCNA) marker and microvessel density (data already published). The present results revealed that VEGF and PCNA expression increased significantly between normal oral tissue and neoplastic tissue, and between well and moderately/poorly differentiated tumours. In addition, VEGF expression was strongly correlated with PCNA expression and microvessel density. It was concluded that VEGF may promote angiogenesis through a paracrine pathway, stimulating endothelial cell proliferation and, similarly, may induce tumour cell proliferation through an autocrine pathway. The present results suggest that the evaluation of VEGF may be a useful additional criterion for estimating malignancy and growth potential in canine OSCCs.

PTB-associated splicing factor inhibits IGF-1-induced VEGF upregulation in a mouse model of oxygen-induced retinopathy.

PubMed

Dong, Lijie; Nian, Hong; Shao, Yan; Zhang, Yan; Li, Qiutang; Yi, Yue; Tian, Fang; Li, Wenbo; Zhang, Hong; Zhang, Xiaomin; Wang, Fei; Li, Xiaorong

2015-05-01

Pathological retinal neovascularization, including retinopathy of prematurity and age-related macular degeneration, is the most common cause of blindness worldwide. Insulin-like growth factor-1 (IGF-1) has a direct mitogenic effect on endothelial cells, which is the basis of angiogenesis. Vascular endothelial growth factor (VEGF) activation in response to IGF-1 is well documented; however, the molecular mechanisms responsible for the termination of IGF-1 signaling are still not completely elucidated. Here, we show that the polypyrimidine tract-binding protein-associated splicing factor (PSF) is a potential negative regulator of VEGF expression induced by IGF stimulation. Functional analysis demonstrated that ectopic expression of PSF inhibits IGF-1-stimulated transcriptional activation and mRNA expression of the VEGF gene, whereas knockdown of PSF increased IGF-1-stimulated responses. PSF recruited Hakai to the VEGF transcription complex, resulting in inhibition of IGF-1-mediated transcription. Transfection with Hakai siRNA reversed the PSF-mediated transcriptional repression of VEGF gene transcription. In summary, these results show that PSF can repress the transcriptional activation of VEGF stimulated by IGF-1 via recruitment of the Hakai complex and delineate a novel regulatory mechanism of IGF-1/VEGF signaling that may have implications in the pathogenesis of neovascularization in ocular diseases.

Vascular Endothelial Growth Factor and Angiogenesis in the Regulation of Cutaneous Wound Repair

PubMed Central

Johnson, Kelly E.; Wilgus, Traci A.

2014-01-01

Significance: Angiogenesis, the growth of new blood vessels from existing vessels, is an important aspect of the repair process. Restoration of blood flow to damaged tissues provides oxygen and nutrients required to support the growth and function of reparative cells. Vascular endothelial growth factor (VEGF) is one of the most potent proangiogenic growth factors in the skin, and the amount of VEGF present in a wound can significantly impact healing. Recent Advances: The activity of VEGF was once considered to be specific for endothelial cells lining the inside of blood vessels, partly because VEGF receptor (VEGFR) expression was believed to be restricted to endothelial cells. It is now known, however, that VEGFRs can be expressed by a variety of other cell types involved in wound repair. For example, keratinocytes and macrophages, which both carry out important functions during wound healing, express VEGFRs and are capable of responding directly to VEGF. Critical Issues: The mechanisms by which VEGF promotes angiogenesis are well established. Recent studies, however, indicate that VEGF can directly affect the activity of several nonendothelial cell types present in the skin. The implications of these extra-angiogenic effects of VEGF on wound repair are not yet known, but they suggest that this growth factor may play a more complex role during wound healing than previously believed. Future Directions: Despite the large number of studies focusing on VEGF and wound healing, it is clear that the current knowledge of how VEGF contributes to the repair of skin wounds is incomplete. Further research is needed to obtain a more comprehensive understanding of VEGF activities during the wound healing process. PMID:25302139

Serum vascular endothelial growth factor in dogs with soft tissue sarcomas.

PubMed

de Queiroz, G Fernandes; Dagli, M Lúcia Zaidan; Meira, S Aparecida; Matera, J Maria

2013-09-01

This work aimed to evaluate serum vascular endothelial growth factor (VEGF) in 25 dogs with soft tissue sarcoma, and in 30 healthy dogs. Blood was collected once time from the control animals and three times, in the same way, from animals with sarcoma. Blood count was performed in the blood collected, and serum VEGF was measured by enzyme-linked immunosorbent assay quantitative method. Serum VEGF in control animals was similar to patients with soft tissue sarcoma. There was a reduction in serum VEGF after the sarcoma resection. There was positive correlation between serum VEGF and neutrophil counts, and negative between VEGF and hemoglobin content in animals with sarcoma. Animals with hemangiopericytoma showed higher serum VEGF levels compared to the patients with malignant peripheral nerve sheath. Circulating blood cells can contribute to elevate VEGF serum concentrations in dogs with soft tissue sarcomas and a possible role of VEGF in the angiogenesis of these tumors. © 2012 John Wiley & Sons Ltd.

The power of VEGF (vascular endothelial growth factor) family molecules.

PubMed

Thomas, Jean-Leon; Eichmann, Anne

2013-05-01

Vascular endothelial growth factors (VEGFs) and their high-affinity tyrosine kinase VEGF receptors (VEGFRs) are key regulators of both angiogenesis and neurogenesis. The current issue of CMLS discusses recent literature and work implementing these signals in nervous system development, maintenance and disease pathology.

Expression of epidermal growth factor receptor and vascular endothelial growth factor in malignant canine epithelial nasal tumours.

PubMed

Shiomitsu, K; Johnson, C L; Malarkey, D E; Pruitt, A F; Thrall, D E

2009-06-01

Epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) signalling pathways play a role in carcinogenesis. Inhibition of EGF receptor (EGFR) and of VEGF is effective in increasing the radiation responsiveness of neoplastic cells both in vitro and in human trials. In this study, immunohistochemical evaluation was employed to determine and characterize the potential protein expression levels and patterns of EGFR and VEGF in a variety of canine malignant epithelial nasal tumours. Of 24 malignant canine nasal tumours, 13 (54.2%) were positive for EGFR staining and 22 (91.7%) were positive for VEGF staining. The intensity and percentage of immunohistochemically positive neoplastic cells for EGFR varied. These findings indicate that EGFR and VEGF proteins were present in some malignant epithelial nasal tumours in the dogs, and therefore, it may be beneficial to treat canine patients with tumours that overexpress EGFR and VEGF with specific inhibitors in conjunction with radiation.

Vascular endothelial growth factors: A comparison between invertebrates and vertebrates.

PubMed

Kipryushina, Yulia O; Yakovlev, Konstantin V; Odintsova, Nelly A

2015-12-01

This review aims to summarize recent data concerning the structure and role of the members of the vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGFR) families in the context of early development, organogenesis and regeneration, with a particular emphasis on the role of these factors in the development of invertebrates. Homologs of VEGF and/or VEGFR have been found in all Eumetazoa, in both Radiata and Bilateria, where they are expressed in the descendants of different germ layers and play a pivotal role in the development of animals with and without a vascular system. VEGF is a well-known angiogenesis regulator, but this factor also control cell migration during neurogenesis and the development of branching organs (the trachea) in invertebrate and vertebrate species. A possible explanation for the origin of Vegf/Vegfr in the animal kingdom and a pathway of Vegf/Vegfr evolution are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nuclear Localization of Vascular Endothelial Growth Factor-D and Regulation of c-Myc–Dependent Transcripts in Human Lung Fibroblasts

PubMed Central

Pacheco-Rodriguez, Gustavo; Malide, Daniela; Meza-Carmen, Victor; Kato, Jiro; Cui, Ye; Padilla, Philip I.; Samidurai, Arun; Gochuico, Bernadette R.

2014-01-01

Lymphangiogenesis and angiogenesis are processes that are, in part, regulated by vascular endothelial growth factor (VEGF)-D. The formation of lymphatic structures has been implicated in multiple lung diseases, including pulmonary fibrosis. VEGF-D is a secreted protein produced by fibroblasts and macrophages, which induces lymphangiogenesis by signaling via VEGF receptor-3, and angiogenesis through VEGF receptor-2. VEGF-D contains a central VEGF homology domain, which is the biologically active domain, with flanking N- and C-terminal propeptides. Full-length VEGF-D (∼ 50 kD) is proteolytically processed in the extracellular space, to generate VEGF homology domain that contains the VEGF-D receptor–binding sites. Here, we report that, independent of its cell surface receptors, full-length VEGF-D accumulated in nuclei of fibroblasts, and that this process appears to increase with cell density. In nuclei, full-length VEGF-D associated with RNA polymerase II and c-Myc. In cells depleted of VEGF-D, the transcriptionally regulated genes appear to be modulated by c-Myc. These findings have potential clinical implications, as VEGF-D was found in fibroblast nuclei in idiopathic pulmonary fibrosis, a disease characterized by fibroblast proliferation. These findings are consistent with actions of full-length VEGF-D in cellular homeostasis in health and disease, independent of its receptors. PMID:24450584

A positive circuit of VEGF increases Glut-1 expression by increasing HIF-1α gene expression in human retinal endothelial cells.

PubMed

Choi, Yoon Kyung

2017-12-01

Treatment of human retinal microvascular endothelial cells (HRMECs) with vascular endothelial growth factor 165 (VEGF 165 ) increased hypoxia-inducible factor 1α (HIF-1α), VEGF, and glucose transporter 1 (Glut-1) mRNA expression and Glut-1 protein localization to the membrane. In contrast, treatment of human retinal pigment epithelium cells with VEGF 165 did not induce HIF-1α, VEGF, and Glut-1 gene expression. Microvascular endothelial cells are surrounded by astrocytic end feet in the retina. Astrocyte-derived A-kinase anchor protein 12 overexpression during hypoxia downregulated VEGF secretion, and this conditioned medium reduced VEGF and Glut-1 expression in HRMECs, suggesting that communications between astrocytes and endothelial cells may be the determinants of the blood vessel network. In HRMECs, HIF-1α small interfering RNA transfection blocked the VEGF 165 -mediated increase in VEGF and Glut-1 gene expression. Inhibition of protein kinase C (PKC) with inhibitor GF109203X or with a small interfering RNA targeting PKCζ attenuated the VEGF 165 -induced Glut-1 protein expression and VEGF and Glut-1 mRNA expression. In addition, results of an immunoprecipitation assay imply an interaction between VEGF receptor 2 (VEGFR2) and PKCζ in HRMECs. Therefore, VEGF secretion by hypoxic astrocytes may upregulate HIF-1α gene expression, inducing VEGF and Glut-1 expression via the VEGFR2-PKCζ axis in HRMECs.

Double-Stranded RNA-Binding Protein Regulates Vascular Endothelial Growth Factor mRNA Stability, Translation, and Breast Cancer Angiogenesis▿

PubMed Central

Vumbaca, Frank; Phoenix, Kathryn N.; Rodriguez-Pinto, Daniel; Han, David K.; Claffey, Kevin P.

2008-01-01

Vascular endothelial growth factor (VEGF) is a key angiogenic factor expressed under restricted nutrient and oxygen conditions in most solid tumors. The expression of VEGF under hypoxic conditions requires transcription through activated hypoxia-inducible factor 1 (HIF-1), increased mRNA stability, and facilitated translation. This study identified double-stranded RNA-binding protein 76/NF90 (DRBP76/NF90), a specific isoform of the DRBP family, as a VEGF mRNA-binding protein which plays a key role in VEGF mRNA stability and protein synthesis under hypoxia. The DRBP76/NF90 protein binds to a human VEGF 3′ untranslated mRNA stability element. RNA interference targeting the DRBP76/NF90 isoform limited hypoxia-inducible VEGF mRNA and protein expression with no change in HIF-1-dependent transcriptional activity. Stable repression of DRBP76/NF90 in MDA-MB-435 breast cancer cells demonstrated reduced polysome-associated VEGF mRNA levels under hypoxic conditions and reduced mRNA stability. Transient overexpression of the DRBP76/NF90 protein increased both VEGF mRNA and protein levels synthesized under normoxic and hypoxic conditions. Cells with stable repression of the DRBP76/NF90 isoform showed reduced tumorigenic and angiogenic potential in an orthotopic breast tumor model. These data demonstrate that the DRBP76/NF90 isoform facilitates VEGF expression by promoting VEGF mRNA loading onto polysomes and translation under hypoxic conditions, thus promoting breast cancer growth and angiogenesis in vivo. PMID:18039850

The prognosis was poorer in colorectal cancers that expressed both VEGF and PROK1 (No correlation coefficient between VEGF and PROK1).

PubMed

Goi, Takanori; Nakazawa, Toshiyuki; Hirono, Yasuo; Yamaguchi, Akio

2015-10-06

The angiogenic proteins vascular endothelial growth factor (VEGF) and prokineticin1 (PROK1) proteins are considered important in colorectal cancer, the relationship between their simultaneous expression and prognosis was investigated in the present study. VEGF and PROK1 expression in 620 primary human colorectal cancer lesions was confirmed via immunohistochemical staining with anti-VEGF and anti-PROK1 antibodies, and the correlation between the expression of these 2 proteins and recurrence/prognosis were investigated. VEGF protein was expressed in 329 (53.1%) and PROK1 protein was expressed in 223 (36.0%). PROK1 and VEGF were simultaneously expressed in 116 (18.7%) of the 620 cases. The correlation coefficient between VEGF expression and PROK1 expression was r = 0.11, and therefore correlation was not observed. Clinical pathology revealed that substantially lymphnode matastasis, hematogenous metastasis, or TMN advanced-stage IV was significantly more prevalent in cases that expressed both VEGF and PROK1 than in the cases negative for both proteins or those positive for only 1 of the proteins. Also the cases positive for both proteins exhibited the worst recurrence and prognosis. In the Cox proportional hazards model, VEGF and PROK1 expression was an independent prognostic factor. The prognosis was poorer in colorectal cancers that expressed both PROK1 and VEGF relative to the cases that expressed only 1 protein, and the expression of both proteins was found to be an independent prognostic factor.

Minoxidil upregulates the expression of vascular endothelial growth factor in human hair dermal papilla cells.

PubMed

Lachgar, S; Charveron, M; Gall, Y; Bonafe, J L

1998-03-01

The hair follicle dermal papilla which controls hair growth, is characterized in the anagen phase by a highly developed vascular network. We have demonstrated in a previous study that the expression of an angiogenic growth factor called vascular endothelial growth factor (VEGF) mRNA varied during the hair cycle. VEGF mRNA is strongly expressed in dermal papilla cells (DPC) in the anagen phase, but during the catagen and telogen phases. VEGF mRNA is less strongly expressed. This involvement of VEGF during the hair cycle allowed us to determine whether VEGF mRNA expression by DPC was regulated by minoxidil. In addition, the effect of minoxidil on VEGF protein synthesis in both cell extracts and DPC-conditioned medium, was investigated immunoenzymatically. Both VEGF mRNA and protein were significantly elevated in treated DPC compared with controls. DPC incubated with increasing minoxidil concentrations (0.2, 2, 6, 12 and 24 mumol/L) induced a dose-dependent expression of VEGF mRNA. Quantification of transcripts showed that DPC stimulated with 24 mumol/L minoxidil express six times more VEGF mRNA than controls. Similarly, VEGF protein production increases in cell extracts and conditioned media following minoxidil stimulation. These studies strongly support the likely involvement of minoxidil in the development of dermal papilla vascularization via a stimulation of VEGF expression, and support the hypothesis that minoxidil has a physiological role in maintaining a good vascularization of hair follicles in androgenetic alopecia.

Differential Receptor Binding and Regulatory Mechanisms for the Lymphangiogenic Growth Factors Vascular Endothelial Growth Factor (VEGF)-C and -D*

PubMed Central

Davydova, Natalia; Harris, Nicole C.; Roufail, Sally; Paquet-Fifield, Sophie; Ishaq, Musarat; Streltsov, Victor A.; Williams, Steven P.; Karnezis, Tara; Stacker, Steven A.; Achen, Marc G.

2016-01-01

VEGF-C and VEGF-D are secreted glycoproteins that induce angiogenesis and lymphangiogenesis in cancer, thereby promoting tumor growth and spread. They exhibit structural homology and activate VEGFR-2 and VEGFR-3, receptors on endothelial cells that signal for growth of blood vessels and lymphatics. VEGF-C and VEGF-D were thought to exhibit similar bioactivities, yet recent studies indicated distinct signaling mechanisms (e.g. tumor-derived VEGF-C promoted expression of the prostaglandin biosynthetic enzyme COX-2 in lymphatics, a response thought to facilitate metastasis via the lymphatic vasculature, whereas VEGF-D did not). Here we explore the basis of the distinct bioactivities of VEGF-D using a neutralizing antibody, peptide mapping, and mutagenesis to demonstrate that the N-terminal α-helix of mature VEGF-D (Phe93–Arg108) is critical for binding VEGFR-2 and VEGFR-3. Importantly, the N-terminal part of this α-helix, from Phe93 to Thr98, is required for binding VEGFR-3 but not VEGFR-2. Surprisingly, the corresponding part of the α-helix in mature VEGF-C did not influence binding to either VEGFR-2 or VEGFR-3, indicating distinct determinants of receptor binding by these growth factors. A variant of mature VEGF-D harboring a mutation in the N-terminal α-helix, D103A, exhibited enhanced potency for activating VEGFR-3, was able to promote increased COX-2 mRNA levels in lymphatic endothelial cells, and had enhanced capacity to induce lymphatic sprouting in vivo. This mutant may be useful for developing protein-based therapeutics to drive lymphangiogenesis in clinical settings, such as lymphedema. Our studies shed light on the VEGF-D structure/function relationship and provide a basis for understanding functional differences compared with VEGF-C. PMID:27852824

Binding affinities of vascular endothelial growth factor (VEGF) for heparin-derived oligosaccharides

PubMed Central

Zhao, Wenjing; McCallum, Scott A.; Xiao, Zhongping; Zhang, Fuming; Linhardt, Robert J.

2011-01-01

Heparin and heparan sulphate (HS) exert their wide range of biological activities by interacting with extracellular protein ligands. Among these important protein ligands are various angiogenic growth factors and cytokines. HS-binding to vascular endothelial growth factor (VEGF) regulates multiple aspects of vascular development and function through its specific interaction with HS. Many studies have focused on HS-derived or HS-mimicking structures for the characterization of VEGF165 interaction with HS. Using a heparinase 1-prepared small library of heparin-derived oligosaccharides ranging from hexasaccharide to octadecasaccharide, we systematically investigated the heparin-specific structural features required for VEGF binding. We report the apparent affinities for the association between the heparin-derived oligosaccharides with both VEGF165 and VEGF55, a peptide construct encompassing exclusively the heparin-binding domain of VEGF165. An octasaccharide was the minimum size of oligosaccharide within the library to efficiently bind to both forms of VEGF and that a tetradecasaccharide displayed an effective binding affinity to VEGF165 comparable to unfractionated heparin. The range of relative apparent binding affinities among VEGF and the panel of heparin-derived oligosaccharides demonstrate that VEGF binding affinity likely depends on the specific structural features of these oligosaccharides including their degree of sulphation and sugar ring stereochemistry and conformation. Notably, the unique 3-O-sulpho group found within the specific antithrombin binding site of heparin is not required for VEGF165 binding. These findings afford new insight into the inherent kinetics and affinities for VEGF association with heparin and heparin-derived oligosaccharides with key residue specific modifications and may potentially benefit the future design of oligosaccharide-based anti-angiogenesis drugs. PMID:21658003

Intracoronary Cytoprotective Gene Therapy: A Study of VEGF-B167 in a Pre-Clinical Animal Model of Dilated Cardiomyopathy.

PubMed

Woitek, Felix; Zentilin, Lorena; Hoffman, Nicholas E; Powers, Jeffery C; Ottiger, Isabel; Parikh, Suraj; Kulczycki, Anna M; Hurst, Marykathryn; Ring, Nadja; Wang, Tao; Shaikh, Farah; Gross, Polina; Singh, Harinder; Kolpakov, Mikhail A; Linke, Axel; Houser, Steven R; Rizzo, Victor; Sabri, Abdelkarim; Madesh, Muniswamy; Giacca, Mauro; Recchia, Fabio A

2015-07-14

Vascular endothelial growth factor (VEGF)-B activates cytoprotective/antiapoptotic and minimally angiogenic mechanisms via VEGF receptors. Therefore, VEGF-B might be an ideal candidate for the treatment of dilated cardiomyopathy, which displays modest microvascular rarefaction and increased rate of apoptosis. This study evaluated VEGF-B gene therapy in a canine model of tachypacing-induced dilated cardiomyopathy. Chronically instrumented dogs underwent cardiac tachypacing for 28 days. Adeno-associated virus serotype 9 viral vectors carrying VEGF-B167 genes were infused intracoronarily at the beginning of the pacing protocol or during compensated heart failure. Moreover, we tested a novel VEGF-B167 transgene controlled by the atrial natriuretic factor promoter. Compared with control subjects, VEGF-B167 markedly preserved diastolic and contractile function and attenuated ventricular chamber remodeling, halting the progression from compensated to decompensated heart failure. Atrial natriuretic factor-VEGF-B167 expression was low in normally functioning hearts and stimulated by cardiac pacing; it thus functioned as an ideal therapeutic transgene, active only under pathological conditions. Our results, obtained with a standard technique of interventional cardiology in a clinically relevant animal model, support VEGF-B167 gene transfer as an affordable and effective new therapy for nonischemic heart failure. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Engineering vascularized soft tissue flaps in an animal model using human adipose–derived stem cells and VEGF+PLGA/PEG microspheres on a collagen-chitosan scaffold with a flow-through vascular pedicle

PubMed Central

Zhang, Qixu; Hubenak, Justin; Iyyanki, Tejaswi; Alred, Erik; Turza, Kristin C.; Davis, Greg; Chang, Edward I.; Branch-Brooks, Cynthia D.; Beahm, Elisabeth K.; Butler, Charles E.

2015-01-01

Insufficient neovascularization is associated with high levels of resorption and necrosis in autologous and engineered fat grafts. We tested the hypothesis that incorporating angiogenic growth factor into a scaffold–stem cell construct and implanting this construct around a vascular pedicle improves neovascularization and adipogenesis for engineering soft tissue flaps. Poly(lactic-co-glycolic-acid/polyethylene glycol (PLGA/PEG) microspheres containing vascular endothelial growth factor (VEGF) were impregnated into collagen-chitosan scaffolds seeded with human adipose-derived stem cells (hASCs). This setup was analyzed in vitro and then implanted into isolated chambers around a discrete vascular pedicle in nude rats. Engineered tissue samples within the chambers were harvested and analyzed for differences in vascularization and adipose tissue growth. In vitro testing showed that the collagen-chitosan scaffold provided a supportive environment for hASC integration and proliferation. PLGA/PEG microspheres with slow-release VEGF had no negative effect on cell survival in collagen-chitosan scaffolds. In vivo, the system resulted in a statistically significant increase in neovascularization that in turn led to a significant increase in adipose tissue persistence after 8 weeks versus control constructs. These data indicate that our model—hASCs integrated with a collagen-chitosan scaffold incorporated with VEGF-containing PLGA/PEG microspheres supported by a predominant vascular vessel inside a chamber—provides a promising, clinically translatable platform for engineering vascularized soft tissue flap. The engineered adipose tissue with a vascular pedicle could conceivably be transferred as a vascularized soft tissue pedicle flap or free flap to a recipient site for the repair of soft-tissue defects. PMID:26410787

Engineering vascularized soft tissue flaps in an animal model using human adipose-derived stem cells and VEGF+PLGA/PEG microspheres on a collagen-chitosan scaffold with a flow-through vascular pedicle.

PubMed

Zhang, Qixu; Hubenak, Justin; Iyyanki, Tejaswi; Alred, Erik; Turza, Kristin C; Davis, Greg; Chang, Edward I; Branch-Brooks, Cynthia D; Beahm, Elisabeth K; Butler, Charles E

2015-12-01

Insufficient neovascularization is associated with high levels of resorption and necrosis in autologous and engineered fat grafts. We tested the hypothesis that incorporating angiogenic growth factor into a scaffold-stem cell construct and implanting this construct around a vascular pedicle improves neovascularization and adipogenesis for engineering soft tissue flaps. Poly(lactic-co-glycolic-acid/polyethylene glycol (PLGA/PEG) microspheres containing vascular endothelial growth factor (VEGF) were impregnated into collagen-chitosan scaffolds seeded with human adipose-derived stem cells (hASCs). This setup was analyzed in vitro and then implanted into isolated chambers around a discrete vascular pedicle in nude rats. Engineered tissue samples within the chambers were harvested and analyzed for differences in vascularization and adipose tissue growth. In vitro testing showed that the collagen-chitosan scaffold provided a supportive environment for hASC integration and proliferation. PLGA/PEG microspheres with slow-release VEGF had no negative effect on cell survival in collagen-chitosan scaffolds. In vivo, the system resulted in a statistically significant increase in neovascularization that in turn led to a significant increase in adipose tissue persistence after 8 weeks versus control constructs. These data indicate that our model-hASCs integrated with a collagen-chitosan scaffold incorporated with VEGF-containing PLGA/PEG microspheres supported by a predominant vascular vessel inside a chamber-provides a promising, clinically translatable platform for engineering vascularized soft tissue flap. The engineered adipose tissue with a vascular pedicle could conceivably be transferred as a vascularized soft tissue pedicle flap or free flap to a recipient site for the repair of soft-tissue defects. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of the secretion and release of vascular endothelial growth factor from two-dimensional culture and three-dimensional cell spheroids formed with stem cells and osteoprecursor cells.

PubMed

Lee, Hyunjin; Lee, Sung-Il; Ko, Youngkyung; Park, Jun-Beom

2018-05-18

Co-culture has been applied in cell therapy, including stem cells, and has been reported to give enhanced functionality. In this study, stem-cell spheroids were formed in concave micromolds at different ratios of stem cells to osteoprecursor cells, and the amount of secretion of vascular endothelial growth factor (VEGF) was evaluated. Gingiva-derived stem cells and osteoprecursor cells in the amount of 6 × 105 were seeded on a 24-well culture plate or concave micromolds. The ratios of stem cells to osteoprecursor cells included: 0:4 (group 1), 1:3 (group 2), 2:2 (group 3), 3:1 (group 4), and 4:0 (group 5). The morphology of cells in a 2-dimensional culture (groups 1-5) showed a fibroblast-like appearance. The secretion of VEGF increased with the increase in stem cells, and a statistically significant increase was noted in groups 3, 4 and 5 when compared with the media-only group (p < 0.05). Osteoprecursor cells formed spheroids in concave microwells, and no noticeable change in the morphology was noted with the increase in stem cells. Spheroids containing stem cells were positive for the stem-cell markers SSEA-4. The secretion of VEGF from cell spheroids increased with the increase in stem cells. This study showed that cell spheroids formed with stem cells and osteoprecursor cells with different ratios, using microwells, had paracrine effects on the stem cells. The secretion of VEGF increased with the increase in stem cells. This stem-cell spheroid may be applied for tissue-engineering purposes.

Hematological and hepatic effects of vascular epidermal growth factor (VEGF) used to stimulate hair growth in an animal model

PubMed Central

2013-01-01

Background Alopecia areata is the hair loss usually reversible, in sharply defined areas. The treatment of alopecia using growth factors shows interesting activity in promoting hair growth. In this concept, VEGF (vascular endothelial growth factor) is a marker of angiogenesis, stimulating hair growth by facilitating the supply of nutrients to the hair follicle, increasing follicular diameter. The aim of this study was the evaluation of a topical gel enriched with VEGF liposomes on the hair growth stimulation and its toxicological aspects. Methods Mesocricetus auratus were randomly divided into three groups. Control group was treated with Aristoflex® gel, 1% group with the same gel but added 1% VEGF and 3% group with 3% VEGF. Biochemical, hematological and histological analyses were done. Results At the end of the experiment (15th day of VEGF treatment) efficacy was determined macroscopically by hair density dermatoscopy analysis, and microscopically by hair diameter analysis. They both demonstrated that hair of the VEGF group increased faster and thicker than control. On the other hand, biochemical and hematological results had shown that VEGF was not 100% inert. Conclusions VEGF increased hair follicle area, but more studies are necessary to confirm its toxicity. PMID:24168457

Protein Kinase D-dependent Phosphorylation and Nuclear Export of Histone Deacetylase 5 Mediates Vascular Endothelial Growth Factor-induced Gene Expression and Angiogenesis*S⃞

PubMed Central

Ha, Chang Hoon; Wang, Weiye; Jhun, Bong Sook; Wong, Chelsea; Hausser, Angelika; Pfizenmaier, Klaus; McKinsey, Timothy A.; Olson, Eric N.; Jin, Zheng-Gen

2008-01-01

Vascular endothelial growth factor (VEGF) is essential for normal and pathological angiogenesis. However, the signaling pathways linked to gene regulation in VEGF-induced angiogenesis are not fully understood. Here we demonstrate a critical role of protein kinase D (PKD) and histone deacetylase 5 (HDAC5) in VEGF-induced gene expression and angiogenesis. We found that VEGF stimulated HDAC5 phosphorylation and nuclear export in endothelial cells through a VEGF receptor 2-phospholipase Cγ-protein kinase C-PKD-dependent pathway. We further showed that the PKD-HDAC5 pathway mediated myocyte enhancer factor-2 transcriptional activation and a specific subset of gene expression in response to VEGF, including NR4A1, an orphan nuclear receptor involved in angiogenesis. Specifically, inhibition of PKD by overexpression of the PKD kinase-negative mutant prevents VEGF-induced HDAC5 phosphorylation and nuclear export as well as NR4A1 induction. Moreover, a mutant of HDAC5 specifically deficient in PKD-dependent phosphorylation inhibited VEGF-mediated NR4A1 expression, endothelial cell migration, and in vitro angiogenesis. These findings suggest that the PKD-HDAC5 pathway plays an important role in VEGF regulation of gene transcription and angiogenesis. PMID:18332134

[Role of VEGF in diseases of the retina].

PubMed

Barquet, Luis Arias

2015-03-01

Angiogenesis is the process through which new blood vessels are formed, based on preexisting vessels, and is the paradigm of diseases such as cancer and exudative ageassociated macular degeneration (ARMD). Several proangiogenic factors have been identified, such as vascular endothelial growth factor (VEGF), especially VEGF-A, which activates endothelial cells and promotes cell proliferation, migration, and an increase in vascular permeability. VEGF is also involved in the etiopathogenesis of other retinal diseases, such as diabetic macular edema and macular edema secondary to retinal vein occlusion. Likewise, there is increasing evidence that placental growth factor (PIGF) acts recepsynergetically with VEGF in promoting these diseases. Currently, the main treatment for these diseases are the anti-VEGF drugs, aflibercept, ranibizumab and bevacizumab. These agents differ in their molecular structure and mechanism of action. Copyright © 2015 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

The DEK oncogene activates VEGF expression and promotes tumor angiogenesis and growth in HIF-1α-dependent and -independent manners

PubMed Central

Li, Yang; Lv, Zhaohui; Zhu, Jie; Lin, Jing; Ding, Lihua; Ye, Qinong

2016-01-01

The DEK oncogene is overexpressed in various cancers and overexpression of DEK correlates with poor clinical outcome. Vascular endothelial growth factor (VEGF) is the most important regulator of tumor angiogenesis, a process essential for tumor growth and metastasis. However, whether DEK enhances tumor angiogenesis remains unclear. Here, we show that DEK is a key regulator of VEGF expression and tumor angiogenesis. Using chromatin immunoprecipitation assay, we found that DEK promoted VEGF transcription in breast cancer cells (MCF7, ZR75-1 and MDA-MB-231) by directly binding to putative DEK-responsive element (DRE) of the VEGF promoter and indirectly binding to hypoxia response element (HRE) upstream of the DRE through its interaction with the transcription factor hypoxia-inducible factor 1α (HIF-1α), a master regulator of tumor angiogenesis and growth. DEK is responsible for recruitment of HIF-1α and the histone acetyltransferase p300 to the VEGF promoter. DEK-enhanced VEGF increases vascular endothelial cell proliferation, migration and tube formation as well as angiogenesis in the chick chorioallantoic membrane. DEK promotes tumor angiogenesis and growth in nude mice in HIF-1α-dependent and -independent manners. Immunohistochemical staining showed that DEK expression positively correlates with the expression of VEGF and microvessel number in 58 breast cancer patients. Our data establish DEK as a sequence-specific binding transcription factor, a novel coactivator for HIF-1α in regulation of VEGF transcription and a novel promoter of angiogenesis. PMID:26988756

EG-VEGF: a key endocrine factor in placental development.

PubMed

Brouillet, Sophie; Hoffmann, Pascale; Feige, Jean-Jacques; Alfaidy, Nadia

2012-10-01

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF), also named prokineticin 1, is the canonical member of the prokineticin family. Numerous reports suggest a direct involvement of this peptide in normal and pathological reproductive processes. Recent advances propose EG-VEGF as a key endocrine factor that controls many aspects of placental development and suggest its involvement in the development of preeclampsia (PE), the most threatening pathology of human pregnancy. This review describes the finely tuned action and regulation of EG-VEGF throughout human pregnancy, argues for its clinical relevance as a potential diagnostic marker of the onset of PE, and discusses future research directions for therapeutic targeting of EG-VEGF. Copyright © 2012 Elsevier Ltd. All rights reserved.

Differential Expression of VEGF-Axxx Isoforms Is Critical for Development of Pulmonary Fibrosis.

PubMed

Barratt, Shaney L; Blythe, Thomas; Jarrett, Caroline; Ourradi, Khadija; Shelley-Fraser, Golda; Day, Michael J; Qiu, Yan; Harper, Steve; Maher, Toby M; Oltean, Sebastian; Hames, Thomas J; Scotton, Chris J; Welsh, Gavin I; Bates, David O; Millar, Ann B

2017-08-15

Fibrosis after lung injury is related to poor outcome, and idiopathic pulmonary fibrosis (IPF) can be regarded as an exemplar. Vascular endothelial growth factor (VEGF)-A has been implicated in this context, but there are conflicting reports as to whether it is a contributory or protective factor. Differential splicing of the VEGF-A gene produces multiple functional isoforms including VEGF-A 165 a and VEGF-A 165 b, a member of the inhibitory family. To date there is no clear information on the role of VEGF-A in IPF. To establish VEGF-A isoform expression and functional effects in IPF. We used tissue sections, plasma, and lung fibroblasts from patients with IPF and control subjects. In a bleomycin-induced lung fibrosis model we used wild-type MMTV mice and a triple transgenic mouse SPC-rtTA +/- TetoCre +/- LoxP-VEGF-A +/+ to conditionally induce VEGF-A isoform deletion specifically in the alveolar type II (ATII) cells of adult mice. IPF and normal lung fibroblasts differentially expressed and responded to VEGF-A 165 a and VEGF-A 165 b in terms of proliferation and matrix expression. Increased VEGF-A 165 b was detected in plasma of progressing patients with IPF. In a mouse model of pulmonary fibrosis, ATII-specific deficiency of VEGF-A or constitutive overexpression of VEGF-A 165 b inhibited the development of pulmonary fibrosis, as did treatment with intraperitoneal delivery of VEGF-A 165 b to wild-type mice. These results indicate that changes in the bioavailability of VEGF-A sourced from ATII cells, namely the ratio of VEGF-A xxx a to VEGF-A xxx b, are critical in development of pulmonary fibrosis and may be a paradigm for the regulation of tissue repair.

Triiodothyronine stimulates VEGF expression and secretion via steroids and HIF-1α in murine Leydig cells.

PubMed

Dhole, Bodhana; Gupta, Surabhi; Venugopal, Senthil Kumar; Kumar, Anand

2018-06-01

Leydig cells are the principal steroidogenic cells of the testis. Leydig cells also secrete a number of growth factors including vascular endothelial growth factor (VEGF) which has been shown to regulate both testicular steroidogenesis and spermatogenesis. The thyroid hormone, T 3, is known to stimulate steroidogenesis in Leydig cells. T 3 has also been shown to stimulate VEGF production in a variety of cell lines. However, studies regarding the effect of T 3 on VEGF synthesis and secretion by the Leydig cells were lacking. Therefore, we investigated the effect of T 3 on VEGF synthesis and secretion in a mouse Leydig tumour cell line, MLTC-1. The effect of T 3 was compared with that of LH/cAMP and hypoxia, two known stimulators of Leydig cell functions. The cells were treated with T 3 , 8-Br-cAMP (a cAMP analogue), or CoCl 2 (a hypoxia mimetic) and VEGF secreted in the cell supernatant was measured using ELISA. The mRNA levels of VEGF were measured by quantitative RT-PCR. In the MLTC-1 cells, T 3 , 8-Br-cAMP, and CoCl 2 stimulated VEGF mRNA levels and the protein secretion. T 3 also increased steroid secretion as well as HIF-1α protein levels, two well-established upstream regulators of VEGF. Inhibitors of steroidogenesis as well as HIF-1α resulted in inhibition of T 3 -stimulated VEGF secretion by the MLTC-1 cells. This suggested a mediatory role of steroids and HIF-1α protein in T 3 -stimulated VEGF secretion by MLTC-1 cells. The mediation by steroids and HIF-1α were independent of each other. 8-Br-cAMP: 8-bromo - 3', 5' cyclic adenosine monophosphate; CoCl 2 : cobalt chloride; HIF-1α: hypoxia inducible factor -1α; LH: luteinizing hormone; T 3 : 3, 5, 3'-L-triiodothyronine; VEGF: vascular endothelial growth factor.

Conditional Switching of Vascular Endothelial Growth Factor (VEGF) Expression in Tumors: Induction of Endothelial Cell Shedding and Regression of Hemangioblastoma-Like Vessels by VEGF Withdrawal

NASA Astrophysics Data System (ADS)

Benjamin, Laura E.; Keshet, Eli

1997-08-01

We have recently shown that VEGF functions as a survival factor for newly formed vessels during developmental neovascularization, but is not required for maintenance of mature vessels. Reasoning that expanding tumors contain a significant fraction of newly formed and remodeling vessels, we examined whether abrupt withdrawal of VEGF will result in regression of preformed tumor vessels. Using a tetracycline-regulated VEGF expression system in xenografted C6 glioma cells, we showed that shutting off VEGF production leads to detachment of endothelial cells from the walls of preformed vessels and their subsequent death by apoptosis. Vascular collapse then leads to hemorrhages and extensive tumor necrosis. These results suggest that enforced withdrawal of vascular survival factors can be applied to target preformed tumor vasculature in established tumors. The system was also used to examine phenotypes resulting from over-expression of VEGF. When expression of the transfected VEGF cDNA was continuously ``on,'' tumors became hyper-vascularized with abnormally large vessels, presumably arising from excessive fusions. Tumors were significantly less necrotic, suggesting that necrosis in these tumors is the result of insufficient angiogenesis.

Lenticular cytoprotection. Part 1: The role of hypoxia inducible factors-1α and -2α and vascular endothelial growth factor in lens epithelial cell survival in hypoxia

PubMed Central

Neelam, Sudha; Brooks, Morgan M.

2013-01-01

Purpose The prosurvival signaling cascades that mediate the unique ability of human lens epithelial cells to survive in their naturally hypoxic environment are not well defined. Hypoxia induces the synthesis of the hypoxia inducible factor HIF-1α that in turn, plays a crucial role in modulating a downstream survival scheme, where vascular endothelial growth factor (VEGF) also plays a major role. To date, no published reports in the lens literature attest to the expression and functionality of HIF-2α and the role it might play in regulating VEGF expression. The aim of this study was to identify the functional expression of the hypoxia inducible factors HIF-1α and HIF-2α and establish their role in regulating VEGF expression. Furthermore, we demonstrate a link between sustained VEGF expression and the ability of the hypoxic human lens epithelial cell to thrive in low oxygen conditions and resist mitochondrial membrane permeability transition (also referred to as lenticular cytoprotection). Methods Hypoxia inducible factor translation inhibitors were used to demonstrate the role of HIF-1α and HIF-2α and the simultaneous expression of both hypoxic inducible factors to determine their role in regulating VEGF expression. Axitinib, which inhibits lenticular cell autophosphorylation of its VEGF receptor, was employed to demonstrate a role for the VEGF–VEGFR2 receptor complex in regulating Bcl-2 expression. Specific antisera and western blot analysis were used to detect the protein levels of HIF-1α and HIF-2α, as well as the proapoptotic protein, BAX and the prosurvival protein, Bcl-2. VEGF levels were analyzed with enzyme-linked immunosorbent assay (ELISA). The potentiometric dye, 5,5′,6,6′-tetrachloro1,1′,3,3′-tetraethyl-benzimidazolylcarbocyanine iodide, was used to determine the effect of the inhibitors on mitochondrial membrane permeability transition. Results Cultured human lens epithelial cells (HLE-B3) maintained under hypoxic condition (1% oxygen) displayed consistent accumulation of VEGF throughout the 72 h incubation period. Using hypoxia inducible factor translation inhibitors targeting HIF-1α or HIF-2α, the specific inhibition of each protein did not diminish VEGF synthesis. The combined inhibition of HIF-1α and HIF-2α expression, using a double hypoxia inducible factor translation inhibitor, markedly decreased the level of VEGF. The inhibition of VEGF synthesis was associated with a profound deficiency in the level of the prosurvival protein, Bcl-2. Axitinib also prevented the VEGF-mediated expression of Bcl-2. The loss of VEGF coupled with the decrease in intracellular Bcl-2 correlated with marked mitochondrial depolarization, an early predictor of cellular apoptosis. Conclusions Our data support a model in which the sustained synthesis of VEGF in human lens epithelial cells, maintained under hypoxic condition, is regulated by a compensatory inter-relationship between HIF-1α and HIF-2α. VEGF acts as a prosurvival factor in hypoxic lens epithelial cells by maintaining consistent expression of the prosurvival protein Bcl-2, which likely prevents the translocation of cytosolic BAX to the outer mitochondrial membrane, thus preventing the initiation of mitochondrial depolarization. PMID:23335846

Placental stress and pre-eclampsia: a revised view.

PubMed

Redman, C W G; Sargent, I L

2009-03-01

In pre-eclampsia, poor placentation causes both oxidative and endoplasmic reticulum stress of the placenta. It is believed placental hypoxia stimulates excessive production of soluble fms-like tyrosine kinase 1 (sFlt-1), which binds and deactivates circulating vascular endothelial growth factor (VEGF). When maternal endothelium is deprived of VEGF it becomes dysfunctional hence leading to the clinical syndrome of the mother. In this paper the previous claim that poor placentation may predispose more to placental oxidative stress than hypoxia is reiterated. We show why pre-eclampsia is not only an endothelial disease, but also a disorder of systemic inflammation. We question that hypoxia is the only or indeed the main stimulus to release of sFlt-1; and emphasise the role of inflammatory mechanisms. Hypoxia cannot be assumed simply because hypoxia-inducible transcription factors (HIF) are upregulated. Concurrent assessments of nuclear factor-kappaB (NF-kappaB), a transcription factor for inflammatory responses are desirable to obtain a more complete picture. We point out that the pre-eclampsia placenta is the source of bioactive circulating factors other than sFlt-1 in concentrations that are much higher than in normal pregnancy. These may also contribute to the final inflammatory syndrome. We propose a modified version of the two-stage model for pre-eclampsia.

Potential role of follicle-stimulating hormone (FSH) and transforming growth factor (TGFβ1) in the regulation of ovarian angiogenesis.

PubMed

Kuo, Shih-Wei; Ke, Ferng-Chun; Chang, Geen-Dong; Lee, Ming-Ting; Hwang, Jiuan-Jiuan

2011-06-01

Angiogenesis occurs during ovarian follicle development and luteinization. Pituitary secreted FSH was reported to stimulate the expression of endothelial mitogen VEGF in granulosa cells. And, intraovarian cytokine transforming growth factor (TGF)β1 is known to facilitate FSH-induced differentiation of ovarian granulosa cells. This intrigues us to investigate the potential role of FSH and TGFβ1 regulation of granulosa cell function in relation to ovarian angiogenesis. Granulosa cells were isolated from gonadotropin-primed immature rats and treated once with FSH and/or TGFβ1 for 48 h, and the angiogenic potential of conditioned media (granulosa cell culture conditioned media; GCCM) was determined using an in vitro assay with aortic ring embedded in collagen gel and immunoblotting. FSH and TGFβ1 increased the secreted angiogenic activity in granulosa cells (FSH + TGFβ1 > FSH ≈ TGFβ1 >control) that was partly attributed to the increased secretion of pro-angiogenic factors VEGF and PDGF-B. This is further supported by the evidence that pre-treatment with inhibitor of VEGF receptor-2 (Ki8751) or PDGF receptor (AG1296) throughout or only during the first 2-day aortic ring culture period suppressed microvessel growth in GCCM-treated groups, and also inhibited the FSH + TGFβ1-GCCM-stimulated release of matrix remodeling-associated gelatinase activities. Interestingly, pre-treatment of AG1296 at late stage suppressed GCCM-induced microvessel growth and stability with demise of endothelial and mural cells. Together, we provide original findings that both FSH and TGFβ1 increased the secretion of VEGF and PDGF-B, and that in turn up-regulated the angiogenic activity in rat ovarian granulosa cells. This implicates that FSH and TGFβ1 play important roles in regulation of ovarian angiogenesis during follicle development. Copyright © 2010 Wiley-Liss, Inc.

Inhibition of VEGF secretion and experimental choroidal neovascularization by picropodophyllin (PPP), an inhibitor of the insulin-like growth factor-1 receptor.

PubMed

Economou, Mario A; Wu, Jiangmei; Vasilcanu, Daiana; Rosengren, Linda; All-Ericsson, Charlotta; van der Ploeg, Ingeborg; Menu, Eline; Girnita, Leonard; Axelson, Magnus; Larsson, Olle; Seregard, Stefan; Kvanta, Anders

2008-11-01

Choroidal neovascularization (CNV) is a debilitating complication of age-related macular degeneration (AMD) and a leading cause of vision loss. Along with other angiogenic factors like vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF-1) and its receptor, IGF-1R, have been implicated in CNV. We have previously shown that the cyclolignan picropodophyllin (PPP) efficiently blocks the insulin-like growth factor-1 receptor (IGF-1R) activity and causes cell death in uveal melanoma cell lines and in an in-vivo model. In this study we investigated the effect of PPP on VEGF expression both in vitro and in vivo and whether this effect has anti-angiogenic consequences in a murine CNV model. C57BL/6J mice with laser-induced CNVs were treated with PPP. Effects on CNV area were assayed by image analysis. VEGF levels in choroids and retinal pigment epithelial cells (APRE-19) were measured by Western blot or ELISA. Transcriptional activation of the VEGF promoter was determined by luciferase reporter gene assay. Mice treated with PPP, administered intraperitoneally or orally, showed 22-32% (p = 0.002) decrease in CNV area. Furthermore, VEGF levels in the choroids were significantly reduced. In cultured APRE-19 cells, IGF-1 was shown to increase VEGF secretion. This increase was completely blocked by PPP. We could confirm that PPP reduced the level of transcriptional activity of VEGF promoter. PPP reduces IGF-1 dependent VEGF expression and CNV in vivo. Accordingly, IGF-1R inhibitors may be useful tools in the therapy of conditions associated with CNV including neovascular AMD.

Inhibition of VEGF secretion and experimental choroidal neovascularization by picropodophyllin (PPP), an inhibitor of the insulin-like growth factor-1 receptor.

PubMed

Economou, Mario A; Wu, Jiangmei; Vasilcanu, Daiana; Rosengren, Linda; All-Ericsson, Charlotta; van der Ploeg, Ingeborg; Menu, Eline; Girnita, Leonard; Axelson, Magnus; Larsson, Olle; Seregard, Stefan; Kvanta, Anders

2008-06-01

Choroidal neovascularization (CNV) is a debilitating complication of age-related macular degeneration (AMD) and a leading cause of vision loss. Along with other angiogenic factors such as vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF)-1 and its receptor, IGF-1R, have been implicated in CNV. A prior study has shown that the cyclolignan picropodophyllin (PPP) efficiently blocks the insulin-like growth factor-1 receptor (IGF-1R) activity and causes cell death in uveal melanoma cell lines and in an in vivo model. In this study we investigated the effect of PPP on VEGF expression, both in vitro and in vivo, and whether this effect has antiangiogenic consequences in a murine CNV model. C57BL/6J mice with laser-induced CNVs were treated with PPP. Effects on CNV area were assayed by image analysis. VEGF levels in the choroid and retinal pigment epithelial cells (ARPE-19) were measured by Western blot or ELISA. Transcriptional activation of the VEGF promoter was determined by luciferase reporter gene assay. Mice treated with PPP, administered intraperitoneally or orally, showed a 22% to 32% (P = 0.002) decrease in CNV area. Furthermore, VEGF levels in the choroid were significantly reduced. In cultured ARPE-19 cells, IGF-1 was shown to increase VEGF secretion. This increase was completely blocked by PPP. PPP reduced the level of transcriptional activity of the VEGF promoter. PPP reduces IGF-1-dependent VEGF expression and CNV in vivo. Accordingly, IGF-1R inhibitors may be useful tools in the treatment of conditions associated with CNV, including neovascular AMD.

Obesity promotes resistance to anti-VEGF therapy in breast cancer by up-regulating IL-6 and potentially FGF-2.

PubMed

Incio, Joao; Ligibel, Jennifer A; McManus, Daniel T; Suboj, Priya; Jung, Keehoon; Kawaguchi, Kosuke; Pinter, Matthias; Babykutty, Suboj; Chin, Shan M; Vardam, Trupti D; Huang, Yuhui; Rahbari, Nuh N; Roberge, Sylvie; Wang, Dannie; Gomes-Santos, Igor L; Puchner, Stefan B; Schlett, Christopher L; Hoffmman, Udo; Ancukiewicz, Marek; Tolaney, Sara M; Krop, Ian E; Duda, Dan G; Boucher, Yves; Fukumura, Dai; Jain, Rakesh K

2018-03-14

Anti-vascular endothelial growth factor (VEGF) therapy has failed to improve survival in patients with breast cancer (BC). Potential mechanisms of resistance to anti-VEGF therapy include the up-regulation of alternative angiogenic and proinflammatory factors. Obesity is associated with hypoxic adipose tissues, including those in the breast, resulting in increased production of some of the aforementioned factors. Hence, we hypothesized that obesity could contribute to anti-VEGF therapy's lack of efficacy. We found that BC patients with obesity harbored increased systemic concentrations of interleukin-6 (IL-6) and/or fibroblast growth factor 2 (FGF-2), and their tumor vasculature was less sensitive to anti-VEGF treatment. Mouse models revealed that obesity impairs the effects of anti-VEGF on angiogenesis, tumor growth, and metastasis. In one murine BC model, obesity was associated with increased IL-6 production from adipocytes and myeloid cells within tumors. IL-6 blockade abrogated the obesity-induced resistance to anti-VEGF therapy in primary and metastatic sites by directly affecting tumor cell proliferation, normalizing tumor vasculature, alleviating hypoxia, and reducing immunosuppression. Similarly, in a second mouse model, where obesity was associated with increased FGF-2, normalization of FGF-2 expression by metformin or specific FGF receptor inhibition decreased vessel density and restored tumor sensitivity to anti-VEGF therapy in obese mice. Collectively, our data indicate that obesity fuels BC resistance to anti-VEGF therapy via the production of inflammatory and angiogenic factors. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Expression of vascular endothelial growth factor mRNA in non-small-cell lung carcinomas

PubMed Central

Fontanini, G; Boldrini, L; Chinè, S; Pisaturo, F; Basolo, F; Calcinai, A; Lucchi, M; Mussi, A; Angeletti, C A; Bevilacqua, G

1999-01-01

The vascular endothelial growth factor (VEGF) has been shown to be strictly related to vascular permeability and endothelial cell growth under physiological and pathological conditions. In tumour development and progression, VEGF plays a pivotal role in the development of the tumoral vascular network, and useful information in the progression of human cancer can be obtained by analysing the vascular endothelial growth factor expression of the tumours. In this study, we investigated the vascular endothelial growth factor transcript expression in non-small-cell lung carcinomas to evaluate the significance of this factor in a group of cancers in which the vascular pattern has been shown to significantly affect progression. Surgical samples of 42 patients with NSCLC were studied using reverse transcription polymerase chain reaction (PCR) analysis and in situ hybridization. Thirty-three out of 42 cases (78.6%) showed VEGF transcript expression predominantly as transcripts for the secretory forms of VEGF (isoforms 121 and 165). In situ hybridization, performed on 24 out of 42 samples, showed that the VEGF transcript expression was in several cases present in the cytoplasm both of neoplastic and normal cells, even if the VEGF mRNA was less expressed in the corresponding non-tumoral part. The VEGF 121 expression was associated with hilar and/or mediastinal nodal involvement (P = 0.02), and, taken together, the VEGF isoforms were shown to significantly influence overall (P = 0.02) and disease-free survival (P = 0.03). As a regulator of tumour angiogenesis, VEGF may represent a useful indicator of progression and poor prognosis in non-small-cell lung carcinomas. © 1999 Cancer Research Campaign PMID:9888482

Differential roles of vascular endothelial growth factor receptors 1 and 2 in dendritic cell differentiation.

PubMed

Dikov, Mikhail M; Ohm, Joyce E; Ray, Neelanjan; Tchekneva, Elena E; Burlison, Jared; Moghanaki, Drew; Nadaf, Sorena; Carbone, David P

2005-01-01

Impaired Ag-presenting function in dendritic cells (DCs) due to abnormal differentiation is an important mechanism of tumor escape from immune control. A major role for vascular endothelial growth factor (VEGF) and its receptors, VEGFR1/Flt-1 and VEGFR2/KDR/Flk-1, has been documented in hemopoietic development. To study the roles of each of these receptors in DC differentiation, we used an in vitro system of myeloid DC differentiation from murine embryonic stem cells. Exposure of wild-type, VEGFR1(-/-), or VEGFR2(-/-) embryonic stem cells to exogenous VEGF or the VEGFR1-specific ligand, placental growth factor, revealed distinct roles of VEGF receptors. VEGFR1 is the primary mediator of the VEGF inhibition of DC maturation, whereas VEGFR2 tyrosine kinase signaling is essential for early hemopoietic differentiation, but only marginally affects final DC maturation. SU5416, a VEGF receptor tyrosine kinase inhibitor, only partially rescued the mature DC phenotype in the presence of VEGF, suggesting the involvement of both tyrosine kinase-dependent and independent inhibitory mechanisms. VEGFR1 signaling was sufficient for blocking NF-kappaB activation in bone marrow hemopoietic progenitor cells. VEGF and placental growth factor affect the early stages of myeloid/DC differentiation. The data suggest that therapeutic strategies attempting to reverse the immunosuppressive effects of VEGF in cancer patients might be more effective if they specifically targeted VEGFR1.

Vascular endothelial growth factor receptor-1 mediates migration of human colorectal carcinoma cells by activation of Src family kinases

PubMed Central

Lesslie, D P; Summy, J M; Parikh, N U; Fan, F; Trevino, J G; Sawyer, T K; Metcalf, C A; Shakespeare, W C; Hicklin, D J; Ellis, L M; Gallick, G E

2006-01-01

Vascular endothelial growth factor (VEGF) is the predominant pro-angiogenic cytokine in human malignancy, and its expression correlates with disease recurrence and poor outcomes in patients with colorectal cancer. Recently, expression of vascular endothelial growth factor receptors (VEGFRs) has been observed on tumours of epithelial origin, including those arising in the colon, but the molecular mechanisms governing potential VEGF-driven biologic functioning in these tumours are not well characterised. In this report, we investigated the role of Src family kinases (SFKs) in VEGF-mediated signalling in human colorectal carcinoma (CRC) cell lines. Vascular endothelial growth factor specifically activated SFKs in HT29 and KM12L4 CRC cell lines. Further, VEGF stimulation resulted in enhanced cellular migration, which was effectively blocked by pharmacologic inhibition of VEGFR-1 or Src kinase. Correspondingly, migration studies using siRNA clones with reduced Src expression confirmed the requirement for Src in VEGF-induced migration in these cells. Furthermore, VEGF treatment enhanced VEGFR-1/SFK complex formation and increased tyrosine phosphorylation of focal adhesion kinase, p130 cas and paxillin. Finally, we demonstrate that VEGF-induced migration is not due, at least in part, to VEGF acting as a mitogen. These results suggest that VEGFR-1 promotes migration of tumour cells through a Src-dependent pathway linked to activation of focal adhesion components that regulate this process. PMID:16685275

Association of polymorphisms in the vascular endothelial growth factor gene and its serum levels with diabetic retinopathy in Chinese patients with type 2 diabetes: a cross-sectional study.

PubMed

Fan, Xiaohong; Wu, Qunhong; Li, Yuan; Hao, Yanhua; Ning, Ning; Kang, Zheng; Cui, Yu; Liu, Ruohong; Han, Liyuan

2014-01-01

Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis, and plays a key role in the pathogenesis of diabetic retinopathy (DR). This study was designed to identify the possible role of VEGF gene polymorphisms in the development of DR in type 2 diabetic patients in Chinese and clarify the relationship between VEGF serum levels and the risk of DR. This cross-sectional study included 1 040 Chinese subjects with type 2 diabetes mellitus. There were 372 patients diagnosed with DR in the case group and 668 patients without DR in the control group. DNA from each patient was analyzed for VEGF polymorphisms of -2578A/C (rs699947), -1154G/A (rs1570360), -460C/T (rs833061), +405C/G (rs2010963), and +936C/T (rs3025039) using MassARRAY compact analyzer. The VEGF serum levels were quantified by enzyme-linked immunosorbent assay (ELISA). No evidence of association was observed between -2578 A/C (rs699947), +405C/G (rs2010963), +936C/T (rs3025039), and DR risk under stringent Bonferroni's correction. However, VEGF serum levels were significantly higher in DR patients than those of control group. The genetic variation of VEGF polymorphisms influenced VEGF serum levels; subjects carrying the VEGF -2578 C/C (rs699947) genotype had greater VEGF serum levels than those carrying the C/A genotype and VEGF serum levels were significantly higher in CC genotype of the +405C/G (rs2010963) compared with those of the other genotypes. The data did not suggest significant association between the VEGF polymorphisms and DR risk under stringent Bonferroni's correction. However, our study indicated that DR patients have higher VEGF levels than diabetic patients without retinopathy, and -2578A/C (rs699947) and +405C/G (rs2010963) may be important factors in determining serum VEGF levels.

Orf virus interleukin-10 and vascular endothelial growth factor-E modulate gene expression in cultured equine dermal fibroblasts.

PubMed

Wise, Lyn M; Bodaan, Christa J; Mercer, Andrew A; Riley, Christopher B; Theoret, Christine L

2016-10-01

Wounds in horses often exhibit sustained inflammation and inefficient vascularization, leading to excessive fibrosis and clinical complications such as "proud flesh". Orf virus-derived proteins, vascular endothelial growth factor (VEGF)-E and interleukin (ovIL)-10, enhance angiogenesis and control inflammation and fibrosis in skin wounds of laboratory animals. The study aimed to determine if equine dermal cells respond to VEGF-E and ovIL-10. Equine dermal cells are expected to express VEGF and IL-10 receptors, so viral protein treatment is likely to alter cellular gene expression and behaviour in a manner conducive to healing. Skin samples were harvested from the lateral thoracic wall of two healthy thoroughbred horses. Equine dermal cells were isolated using a skin explant method and their phenotype assessed by immunofluorescence. Cells were treated with recombinant proteins, with or without inflammatory stimuli. Gene expression was examined using standard and quantitative reverse transcriptase PCR. Cell behaviour was evaluated in a scratch assay. Cultured cells were half vimentin(+ve) fibroblasts and half alpha smooth muscle actin(+ve) and vimentin(+ve) myofibroblasts. VEGF-E increased basal expression of IL-10 mRNA, whereas VEGF-A and collagenase-1 mRNA expression was increased by ovIL-10. In cells exposed to inflammatory stimulus, both treatments dampened tumour necrosis factor mRNA expression, and ovIL-10 exacerbated expression of monocyte chemoattractant protein. Neither viral protein influenced cell migration greatly. This study shows that VEGF-E and ovIL-10 are active on equine dermal cells and exert anti-inflammatory and anti-fibrotic effects that may enhance skin wound healing in horses. © 2016 ESVD and ACVD.

Chronic Ethanol consumption modulates growth factor release, mucosal cytokine production and microRNA expression in nonhuman primates

PubMed Central

Asquith, Mark; Pasala, Sumana; Engelmann, Flora; Haberthur, Kristen; Meyer, Christine; Park, Byung; Grant, Kathleen A.; Messaoudi, Ilhem

2013-01-01

BACKGROUND Chronic alcohol consumption has been associated with enhanced susceptibility to both systemic and mucosal infections. However, the exact mechanisms underlying this enhanced susceptibility remain incompletely understood. METHODS Using a nonhuman primate model of ethanol self-administration, we examined the impact of chronic alcohol exposure on immune homeostasis, cytokine and growth factor production in peripheral blood, lung and intestinal mucosa following twelve months of chronic ethanol exposure. RESULTS Ethanol exposure inhibited activation-induced production of growth factors HGF, G-CSF and VEGF by peripheral blood mononuclear cells (PBMC). Moreover, ethanol significantly reduced the frequency of colonic Th1 and Th17 cells in a dose-dependent manner. In contrast, we did not observe differences in lymphocyte frequency or soluble factor production in the lung of ethanol-consuming animals. To uncover mechanisms underlying reduced growth factor and Th1/Th17 cytokine production, we compared expression levels of microRNAs in PBMC and intestinal mucosa. Our analysis revealed ethanol-dependent upregulation of distinct microRNAs in affected tissues (miR-181a and miR-221 in PBMC; miR-155 in colon). Moreover, we were able to detect reduced expression of the transcription factors STAT3 and ARNT, which regulate expression of VEGF, G-CSF and HGF and contain targets for these microRNAs. To confirm and extend these observations, PBMC were transfected with either mimics or antagomirs of miR181 and 221and protein levels of the transcription factors and growth factors were determined. Transfection of microRNA mimics led to a reduction in both STAT-3/ARNT as well as VEGF/HGF/G-CSF levels. The opposite outcome was observed when microRNA antagomirs were transfected CONCLUSION Chronic ethanol consumption significantly disrupts both peripheral and mucosal immune homeostasis, and this dysregulation may be mediated by changes in microRNA expression. PMID:24329418

Ovarian hyperstimulation syndrome is correlated with a reduction of soluble VEGF receptor protein level and a higher amount of VEGF-A.

PubMed

Pietrowski, D; Szabo, L; Sator, M; Just, A; Egarter, C

2012-01-01

Ovarian hyperstimulation syndrome (OHSS) is a potentially life-threatening condition associated with increased vascular permeability. The vascular endothelial growth factor (VEGF) system and its receptors have been identified as the main angiogenic factors responsible for increased capillary permeability and are therefore discussed as crucial for the occurrence of OHSS. Recently, a number of soluble receptors for the VEGFs have been detected (sVEGF-Rs) and it has been shown that these sVEGF-Rs compete with the membrane-standing VEGF-R to bind VEGFs. We analyzed the serum levels of soluble VEGF-R1, -R2 and -R3 in 34 patients suffering from OHSS and in 34 controls without this disease. In a subgroup analysis, we correlated the severity of the OHSS with the detected amounts of VEGF-R1, -R2 and -R3. In addition, we determined the amount of total VEGF-A in the samples. All the three soluble VEGF receptors tended to be higher in the control group compared with that in the OHSS group but this difference only reached significance for sVEGF-R2 (mean ± SEM: 15.5 ± 0.6 versus 13.8 ± 0.5 ng/ml, respectively, P< 0.05). In the subgroup analysis, sVEGF-R2 levels decreased as the severity of OHSS increased (OHSS-I: 16.8 ± 1.9 ng/ml and OHSS-III: 12.7 ± 1.0 ng/ml, P< 0.05) Moreover, the serum levels of total VEGF-A were higher in the OHSS group than those in the controls (537.7 ± 38.9 versus 351 ± 53.4 pg/ml, respectively P< 0.05). We propose that VEGF-A plays a role in the occurrence of OHSS, that the amount of biologically available VEGF-A is modulated by sVEGF-Rs and that different combinations of VEGF-A and sVEGF-R levels might contribute to the severity of OHSS.

Vascular Endothelial Growth Factor and Angiopoietin-1 Stimulate Postnatal Hematopoiesis by Recruitment of Vasculogenic and Hematopoietic Stem Cells

PubMed Central

Hattori, Koichi; Dias, Sergio; Heissig, Beate; Hackett, Neil R.; Lyden, David; Tateno, Masatoshi; Hicklin, Daniel J.; Zhu, Zhenping; Witte, Larry; Crystal, Ronald G.; Moore, Malcolm A.S.; Rafii, Shahin

2001-01-01

Tyrosine kinase receptors for angiogenic factors vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) are expressed not only by endothelial cells but also by subsets of hematopoietic stem cells (HSCs). To further define their role in the regulation of postnatal hematopoiesis and vasculogenesis, VEGF and Ang-1 plasma levels were elevated by injecting recombinant protein or adenoviral vectors expressing soluble VEGF165, matrix-bound VEGF189, or Ang-1 into mice. VEGF165, but not VEGF189, induced a rapid mobilization of HSCs and VEGF receptor (VEGFR)2+ circulating endothelial precursor cells (CEPs). In contrast, Ang-1 induced delayed mobilization of CEPs and HSCs. Combined sustained elevation of Ang-1 and VEGF165 was associated with an induction of hematopoiesis and increased marrow cellularity followed by proliferation of capillaries and expansion of sinusoidal space. Concomitant to this vascular remodeling, there was a transient depletion of hematopoietic activity in the marrow, which was compensated by an increase in mobilization and recruitment of HSCs and CEPs to the spleen resulting in splenomegaly. Neutralizing monoclonal antibody to VEGFR2 completely inhibited VEGF165, but not Ang-1–induced mobilization and splenomegaly. These data suggest that temporal and regional activation of VEGF/VEGFR2 and Ang-1/Tie-2 signaling pathways are critical for mobilization and recruitment of HSCs and CEPs and may play a role in the physiology of postnatal angiogenesis and hematopoiesis. PMID:11342585

The Angio-Fibrotic Switch of VEGF and CTGF in Proliferative Diabetic Retinopathy

PubMed Central

Kuiper, Esther J.; Van Nieuwenhoven, Frans A.; de Smet, Marc D.; van Meurs, Jan C.; Tanck, Michael W.; Oliver, Noelynn; Klaassen, Ingeborg; Van Noorden, Cornelis J. F.; Goldschmeding, Roel; Schlingemann, Reinier O.

2008-01-01

Background In proliferative diabetic retinopathy (PDR), vascular endothelial growth factor (VEGF) and connective tissue growth factor (CTGF) cause blindness by neovascularization and subsequent fibrosis, but their relative contribution to both processes is unknown. We hypothesize that the balance between levels of pro-angiogenic VEGF and pro-fibrotic CTGF regulates angiogenesis, the angio-fibrotic switch, and the resulting fibrosis and scarring. Methods/Principal Findings VEGF and CTGF were measured by ELISA in 68 vitreous samples of patients with proliferative DR (PDR, N = 32), macular hole (N = 13) or macular pucker (N = 23) and were related to clinical data, including degree of intra-ocular neovascularization and fibrosis. In addition, clinical cases of PDR (n = 4) were studied before and after pan-retinal photocoagulation and intra-vitreal injections with bevacizumab, an antibody against VEGF. Neovascularization and fibrosis in various degrees occurred almost exclusively in PDR patients. In PDR patients, vitreous CTGF levels were significantly associated with degree of fibrosis and with VEGF levels, but not with neovascularization, whereas VEGF levels were associated only with neovascularization. The ratio of CTGF and VEGF was the strongest predictor of degree of fibrosis. As predicted by these findings, patients with PDR demonstrated a temporary increase in intra-ocular fibrosis after anti-VEGF treatment or laser treatment. Conclusions/Significance CTGF is primarily a pro-fibrotic factor in the eye, and a shift in the balance between CTGF and VEGF is associated with the switch from angiogenesis to fibrosis in proliferative retinopathy. PMID:18628999

VEGF and VEGFB Play Balancing Roles in Adipose Differentiation, Gene Expression, and Function.

PubMed

Jin, Honghong; Li, Dan; Wang, Xutong; Jia, Jia; Chen, Yang; Yao, Yapeng; Zhao, Chunlan; Lu, Xiaodan; Zhang, Shujie; Togo, Jacques; Ji, Yan; Zhang, Luqing; Feng, Xuechao; Zheng, Yaowu

2018-05-01

Obesity is the result of abnormal adipose development and energy metabolism. Using vascular endothelial growth factor (VEGF) B-knockout and inducible VEGF downregulation mouse models, we have shown that VEGFB inactivation caused expansion of white adipose, whitening of brown adipose, an increase in fat accumulation, and a reduction in energy consumption. At the same time, expression of the white adipose-associated genes was increased and brown adipose-associated genes decreased. VEGF repression, in contrast, induced brown adipose expansion and brown adipocyte development in white adipose, increased energy expenditure, upregulated brown adipose-associated genes, and downregulated white adipose-associated genes. When VEGFB-knockout and VEGF-repressed mice are crossed together, VEGF and VEGFB can counteractively regulate large numbers of genes and efficiently reverse each other's roles. These genes, under counteractive VEGF and VEGFB regulations, include transcription factors, adhesion molecules, and metabolic enzymes. This balancing role is confirmed by morphologic and functional changes. This study reports that VEGF and VEGFB counteractively regulate adipose development and function in energy metabolism.

The regulation of vascular endothelial growth factor-induced microvascular permeability requires Rac and reactive oxygen species.

PubMed

Monaghan-Benson, Elizabeth; Burridge, Keith

2009-09-18

Vascular permeability is a complex process involving the coordinated regulation of multiple signaling pathways in the endothelial cell. It has long been documented that vascular endothelial growth factor (VEGF) greatly enhances microvascular permeability; however, the molecular mechanisms controlling VEGF-induced permeability remain unknown. Treatment of microvascular endothelial cells with VEGF led to an increase in reactive oxygen species (ROS) production. ROS are required for VEGF-induced permeability as treatment with the free radical scavenger, N-acetylcysteine, inhibited this effect. Additionally, treatment with VEGF caused ROS-dependent tyrosine phosphorylation of both vascular-endothelial (VE)-cadherin and beta-catenin. Rac1 was required for the VEGF-induced increase in permeability and adherens junction protein phosphorylation. Knockdown of Rac1 inhibited VEGF-induced ROS production consistent with Rac lying upstream of ROS in this pathway. Collectively, these data suggest that VEGF leads to a Rac-mediated generation of ROS, which, in turn, elevates the tyrosine phosphorylation of VE-cadherin and beta-catenin, ultimately regulating adherens junction integrity.

Tristetraprolin Inhibits Ras-dependent Tumor Vascularization by Inducing Vascular Endothelial Growth Factor mRNA Degradation

PubMed Central

Essafi-Benkhadir, Khadija; Onesto, Cercina; Stebe, Emmanuelle; Moroni, Christoph

2007-01-01

Vascular endothelial growth factor (VEGF) is one of the most important regulators of physiological and pathological angiogenesis. Constitutive activation of the extracellular signal-regulated kinase (ERK) pathway and overexpression of VEGF are common denominators of tumors from different origins. We have established a new link between these two fundamental observations converging on VEGF mRNA stability. In this complex phenomenon, tristetraprolin (TTP), an adenylate and uridylate-rich element-associated protein that binds to VEGF mRNA 3′-untranslated region, plays a key role by inducing VEGF mRNA degradation, thus maintaining basal VEGF mRNA amounts in normal cells. ERKs activation results in the accumulation of TTP mRNA. However, ERKs reduce the VEGF mRNA-destabilizing effect of TTP, leading to an increase in VEGF expression that favors the angiogenic switch. Moreover, TTP decreases RasVal12-dependent VEGF expression and development of vascularized tumors in nude mice. As a consequence, TTP might represent a novel antiangiogenic and antitumor agent acting through its destabilizing activity on VEGF mRNA. Determination of TTP and ERKs status would provide useful information for the evaluation of the angiogenic potential in human tumors. PMID:17855506

Vascular endothelial growth factor upregulation in transient global ischemia induced by cardiac arrest and resuscitation in rat brain.

PubMed

Pichiule, P; Chávez, J C; Xu, K; LaManna, J C

1999-12-10

This study examined vascular endothelial growth factor (VEGF) expression in rat brain after reversible global cerebral ischemia produced by cardiac arrest and resuscitation. Three alternative splicing forms, VEGF(188), VEGF(164) and VEGF(120), were observed in cortex, hippocampus and brainstem by RT-PCR analysis. After 24 h of recovery from cardiac arrest, mRNA levels corresponding to VEGF(188) and VEGF(164) were significantly increased by about double in all the regions analyzed. These mRNA levels remained elevated at 24 and 48 h of recovery but returned to basal expression after 7 days of recovery. Changes in VEGF(120) expression after cardiac arrest did not reach statistical significance. VEGF protein expression measured by Western blot was also increased by about double at 24 and 48 h of recovery but returned to control levels after 7 days of recovery. VEGF immunohistochemistry localized this increased expression mostly associated with astrocytes. Considering its biological activity, VEGF induction after cardiac arrest and resuscitation may be responsible for the increased vascular permeability and the resultant vasogenic edema, found 24-48 h after reversible global ischemia.

Gelatin device for the delivery of growth factors involved in endochondral ossification.

PubMed

Ahrens, Lucas A J; Vonwil, Daniel; Christensen, Jon; Shastri, V Prasad

2017-01-01

Controlled release drug delivery systems are well established as oral and implantable dosage forms. However, the controlled release paradigm can also be used to present complex soluble signals responsible for cellular organization during development. Endochondral ossification (EO), the developmental process of bone formation from a cartilage matrix is controlled by several soluble signals with distinct functions that vary in structure, molecular weight and stability. This makes delivering them from a single vehicle rather challenging. Herein, a gelatin-based delivery system suitable for the delivery of small molecules as well as recombinant human (rh) proteins (rhWNT3A, rhFGF2, rhVEGF, rhBMP4) is reported. The release behavior and biological activity of the released molecules was validated using analytical and biological assays, including cell reporter systems. The simplicity of fabrication of the gelatin device should foster its adaptation by the diverse scientific community interested in interrogating developmental processes, in vivo.

Gelatin device for the delivery of growth factors involved in endochondral ossification

PubMed Central

Ahrens, Lucas A. J.; Vonwil, Daniel; Christensen, Jon

2017-01-01

Controlled release drug delivery systems are well established as oral and implantable dosage forms. However, the controlled release paradigm can also be used to present complex soluble signals responsible for cellular organization during development. Endochondral ossification (EO), the developmental process of bone formation from a cartilage matrix is controlled by several soluble signals with distinct functions that vary in structure, molecular weight and stability. This makes delivering them from a single vehicle rather challenging. Herein, a gelatin-based delivery system suitable for the delivery of small molecules as well as recombinant human (rh) proteins (rhWNT3A, rhFGF2, rhVEGF, rhBMP4) is reported. The release behavior and biological activity of the released molecules was validated using analytical and biological assays, including cell reporter systems. The simplicity of fabrication of the gelatin device should foster its adaptation by the diverse scientific community interested in interrogating developmental processes, in vivo. PMID:28380024

Serum vascular endothelial growth factor A levels reflect itch severity in mycosis fungoides and Sézary syndrome.

PubMed

Sakamoto, Minami; Miyagaki, Tomomitsu; Kamijo, Hiroaki; Oka, Tomonori; Takahashi, Naomi; Suga, Hiraku; Yoshizaki, Ayumi; Asano, Yoshihide; Sugaya, Makoto; Sato, Shinichi

2018-01-01

Angiogenesis is an important step to support progression of malignancies, including mycosis fungoides (MF) and Sézary syndrome (SS). Vascular endothelial growth factor (VEGF)-A, a key player in angiogenesis, is secreted by tumor cells of MF/SS and its expression levels in lesional skin correlated with disease severity. In this study, we examined serum VEGF-A levels in MF/SS patients. Serum VEGF-A levels were elevated in patients with erythrodermic MF/SS and the levels decreased after treatment. Importantly, serum VEGF-A levels positively correlated with markers for pruritus. We also found that VEGF-A upregulated mRNA expression of thymic stromal lymphopoietin by keratinocytes. Taken together, our study suggests that VEGF-A can promote progression and pruritus in MF/SS. Inhibition of VEGF-A signaling can be a therapeutic strategy for patients with erythrodermic MF/SS. © 2017 Japanese Dermatological Association.

Effect of local neutralization of basic fibroblast growth factor or vascular endothelial growth factor by a specific antibody on the development of the corpus luteum in the cow.

PubMed

Yamashita, Hiromichi; Kamada, Daichi; Shirasuna, Koumei; Matsui, Motozumi; Shimizu, Takashi; Kida, Katsuya; Berisha, Bajram; Schams, Dieter; Miyamoto, Akio

2008-09-01

Active angiogenesis and progesterone (P) synthesis occur in parallel during development of the corpus luteum (CL). Basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) are known to stimulate angiogenesis and P synthesis in vitro. The aim of the present study was to investigate the impact of bFGF or VEGF on the CL development in the cow by using a specific antibody against bFGF or VEGF. bFGF antibody, VEGF antibody, or saline as a control (n = 4 cows/treatment) were injected directly into the CL immediately after ovulation (Day 1), and the treatment was continued for 3 times/day over 7 days. Luteal biopsies were applied on Day 8 of the estrous cycle to determine the expression of genes associated with P synthesis and angiogenesis. Intraluteal injections with the bFGF antibody or the VEGF antibody markedly decreased the CL volume, plasma P concentration and StAR mRNA expression. bFGF antibody treatment decreased the mRNA expression of bFGF, FGF receptor-1, VEGF120, and angiopoietin (ANPT)-1, and increased ANPT-2/ANPT-1 ratio. However, VEGF antibody treatment decreased ANPT-2 mRNA expression and ANPT-2/ANPT-1 ratio. These results indicate that local neutralization of bFGF or VEGF changes genes regulating angiogenesis and P synthesis, and remarkably suppresses the CL size and P secretion during the development of CL in the cow, supporting the concept that bFGF and VEGF control the CL formation and function.

Alginate Sulfates Mitigate Binding Kinetics of Proangiogenic Growth Factors with Receptors toward Revascularization.

PubMed

Schmidt, John; Lee, Min Kyung; Ko, Eunkyung; Jeong, Jae Hyun; DiPietro, Luisa A; Kong, Hyunjoon

2016-07-05

Ever since proangiogenic growth factors have been used as a vascular medicine to treat tissue ischemia, efforts have been increasingly made to develop a method to enhance efficacy of growth factors in recreating microvascular networks, especially at low dose. To this end, we hypothesized that polysaccharides substituted with sulfate groups would amplify growth factor receptor activation and stimulate phenotypic activities of endothelial cells involved in neovascularization. We examined this hypothesis by modifying alginate with a controlled number of sulfates and using it to derive a complex with vascular endothelial growth factor (VEGF), as confirmed with fluorescence resonance energy transfer (FRET) assay. Compared with the bare VEGF and with a mixture of VEGF and unmodified alginates, the VEGF complexed with alginate sulfates significantly reduced the dissociation rate with the VEGFR-2, elevated VEGFR-2 phosphorylation level, and increased the number of endothelial sprouts in vitro. Furthermore, the VEGF-alginate sulfate complex improved recovery of perfusion in an ischemic hindlimb of a mouse due to the increase of the capillary density. Overall, this study not only demonstrates an important cofactor of VEGF but also uncovers an underlying mechanism by which the cofactor mitigates the VEGF-induced signaling involved in the binding kinetics and activation of VEGFR. We therefore believe that the results of this study will be highly useful in improving the therapeutic efficacy of various growth factors and expediting their uses in clinical treatments of wounds and tissue defects.

TNF-alpha and endotoxin increase hypoxia-induced VEGF production by cultured human nasal fibroblasts in synergistic fashion.

PubMed

Sun, Dong; Matsune, Shoji; Ohori, Junichiro; Fukuiwa, Tatsuya; Ushikai, Masato; Kurono, Yuichi

2005-09-01

Vascular endothelial growth factor (VEGF) promotes angiogenesis and is associated with the invasion and metastasis of malignant tumors. It enhances vascular permeability and is expressed in inflammatory nasal as well as middle-ear mucosa. As the mechanism of VEGF induction during chronic inflammation, such as chronic paranasal sinusitis (CPS) remains to be clarified, we studied the factors regulating the production of VEGF in cultured human nasal fibroblasts and discussed the role of VEGF in the pathogenesis of CPS. We used ELISA to quantify VEGF levels in paranasal sinus effusions, nasal secretions, and serum from patients with CPS. In addition, we cultured human nasal fibroblasts isolated from nasal polyps of CPS patients and studied the effects of hypoxia, TNF-alpha, and endotoxin on their production of VEGF using ELISA and PCR. The VEGF concentration was significantly higher in paranasal sinus effusions than in nasal secretions and serum. Nasal fibroblasts produced high levels of VEGF, when cultured under hypoxic condition and this production was remarkably enhanced in the presence of TNF-alpha or endotoxin. VEGF is locally produced in paranasal sinuses as well as nasal mucosa and its production is increased in patients with CPS. Hypoxia is associated with the production of VEGF by nasal fibroblasts and TNF-alpha and endotoxin may act synergistically to enhance VEGF production in paranasal sinuses under hypoxic condition.

In vitro and in vivo evaluation of a small-caliber coaxial electrospun vascular graft loaded with heparin and VEGF.

PubMed

Hu, Yun-Tao; Pan, Xu-Dong; Zheng, Jun; Ma, Wei-Guo; Sun, Li-Zhong

2017-08-01

To date, clinically available expanded polytetrafluoro-ethylene (ePTFE) vascular grafts are suboptimal for reconstructing small caliber (D < 6 mm) arteries, owing to thrombosis in early and restenosis in late stage. Our aim in this preliminary study was to fabricate a nano-fibrous vascular graft which was biofunctionalized with VEGF 165 and heparin. The short term performance was evaluated both in vitro and in vivo. Four-mm caliber grafts were prepared by the coaxial-elctrospun technique, which consisted of poly(l-lactide-co-caprolactone) [P(LLA-CL)] collagen and elastin. Heparin and endothelial cell growth factor-165 (VEGF 165 ) were encapsulated in the core of the fibrous. Controlled release of the heparin and VEGF 165 were evaluated for 28 days. Endothelial cells were cultured on the electrospun grafts or ePTFE grafts as controls. The cellular adhesion, proliferation and morphology were examined. Electrospun or ePTFE grafts were randomly implanted into a rabbit infrarenal aortic replacement model (n = 30) for 28 days without any antiplatelet therapy. At the termination, all grafts were examined by Doppler ultrasound and then evaluated with histology and scanning electron microscopy. The cumulative release amount of heparin (6.93 ± 1.03 mg) and VEGF 165 (22.17 ± 5.56 μg) during 28 days were measured. Endothelial cells cultured on electrospun grafts showed significantly higher attachment efficiency and proliferation compared to the ePTFE ones (P < 0.001). At 2 h more ECs had attached to the P(LLA-CL)/Collagen/Elatin grafts (83.26 ± 8.02%) compared to P(LLA-CL) (67.07 ± 4.16%) and ePTFE (46.87 ± 8.85%). ECs proliferated faster on VEGF loaded grafts (O.D = 2.9 ± 1.2, n = 12) compared to ePTFE (O.D = 1.7 ± 1.0, n = 12). The patency was significantly higher in electrospun grafts (86.6%) than ePTFE grafts (40.0%) (P = 0.021). Correspondingly, the microscope images of electrospun implants showed little thrombus when compared with the ePTFE implants. Biofunctionalized electrospun graft showed surgical properties, hemocompatibility and higher short-term patency compared with the ePTFE grafts. Despite good early performances, profound study should be designed for long-term evaluation. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Abnormal angiopoietins 1&2, angiopoietin receptor Tie-2 and vascular endothelial growth factor levels in hypertension: relationship to target organ damage [a sub-study of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT)].

PubMed

Nadar, S K; Blann, A; Beevers, D G; Lip, G Y H

2005-10-01

The increased risk of target organ damage (TOD) in hypertension may be related to a prothrombotic or hypercoagulable state, with abnormalities in platelet activation. Altered angiogenesis, possibly related to increased plasma vascular endothelial growth factor (VEGF) is also a feature of hypertension. We hypothesized a link between altered angiogenesis and TOD in hypertension. Accordingly, the angiogenic growth factors VEGF, angiopoietin 1 and 2 (Ang 1 & 2) and soluble angiopoietin receptor Tie-2 in plasma and in platelets were assessed in terms of the presence or absence of hypertensive TOD. We studied 199 patients (75% men; mean age 68 years) with hypertension. Of these, 125 had evidence of hypertensive TOD (stroke, previous myocardial infarction, angina, left ventricular hypertrophy and mild renal failure). Patients were compared with 74 healthy normotensive controls (69% men; mean age 68 years). Plasma VEGF, Ang 1 & 2 and Tie-2, and total platelet levels of VEGF and Ang-1 (obtained by lysing a known number of platelets with 0.5% Tween) were measured by an enzyme-linked immunosorbent assay. Hypertensive patients had higher levels of plasma VEGF, Ang-1, Ang-2, Tie-2 and platelet VEGF (all P

Differential Regulation of Angiogenesis using Degradable VEGF-Binding Microspheres

PubMed Central

Belair, David G.; Miller, Michael J.; Wang, Shoujian; Darjatmokon, Soesiawati R.; Binder, Bernard Y.K.; Sheibani, Nader; Murphy, William L.

2016-01-01

Vascular endothelial growth factor (VEGF) spatial and temporal activity must be tightly controlled during angiogenesis to form perfusable vasculature in a healing wound. The native extracellular matrix (ECM) regulates growth factor activity locally via sequestering, and researchers have used ECM-mimicking approaches to regulate the activity of VEGF in cell culture and in vivo. However, the impact of dynamic, affinity-mediated growth factor sequestering has not been explored in detail with biomaterials. Here, we sought to modulate VEGF activity dynamically over time using poly(ethylene glycol) microspheres containing VEGF-binding peptides (VBPs) and exhibiting varying degradation rates. The degradation rate of VBP microspheres conferred a differential ability to up- or down-regulate VEGF activity in culture with primary human endothelial cells. VBP microspheres with fast-degrading crosslinks reduced VEGF activity and signaling, while VBP microspheres with no inherent degradability sequestered and promoted VEGF activity in culture with endothelial cells. VBP microspheres with degradable crosslinks significantly reduced neovascularization in vivo, but neither non-degradable VBP microspheres nor bolus delivery of soluble VBP reduced neovascularization. The covalent incorporation of VBP to degradable microspheres was required to reduce neovascularization in a mouse model of choroidal neovascularization in vivo, which demonstrates a potential clinical application of degradable VBP microspheres to reduce pathological angiogenesis. The results herein highlight the ability to modulate the activity of a sequestered growth factor by changing the crosslinker identity within PEG hydrogel microspheres. The insights gained here may instruct the design and translation of affinity-based growth factor sequestering biomaterials for regenerative medicine applications. PMID:27061268

Induction of an angiogenic phenotype in endometriotic stromal cell cultures by interleukin-1beta.

PubMed

Lebovic, D I; Bentzien, F; Chao, V A; Garrett, E N; Meng, Y G; Taylor, R N

2000-03-01

Activated peritoneal macrophages are associated with endometriosis and may play a central role in its aetiology by releasing interleukin-1beta (IL-1beta) in response to refluxed endometrium. Pari passu with the establishment of endometriotic implants is the development of a vascular supply. In this study we investigated the angiogenic properties of two endometrial proteins, vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6), and assessed their production in response to IL-1beta stimulation in human stromal cells isolated from normal endometrium (NE) and endometriotic lesions (EI). Proliferation of bovine brain capillary endothelial cells (BBCE) with a [(3)H]-thymidine incorporation assay was observed when VEGF (2.1 +/- 0.2-fold; P < 0.05) or VEGF and IL-6 (1.8 +/- 0.1-fold; P < 0.05) were added in vitro, relative to saline-treated control cultures. Northern blot analysis showed induction of VEGF mRNA (2.6-fold; P < 0.05) and IL-6 mRNA (6.3-fold; P < 0.05) transcripts in EI cells, but not NE cells, exposed to IL-1beta. A similar induction was seen with VEGF and IL-6 protein secretion in the responsive EI cells. Reverse transcription-polymerase chain reaction (RT-PCR) for the IL-1 receptor type I (IL-1 RI) indicated that the differential effects of IL-1beta on NE and EI cells was associated with 2.4 +/- 0.1-fold more receptor mRNA in EI versus NE cells. We propose that the ability of IL-1beta to activate an angiogenic phenotype in EI stromal cells but not in NE cells, is mediated by the IL-1 RI.

Perlecan Domain V Induces VEGf Secretion in Brain Endothelial Cells through Integrin α5β1 and ERK-Dependent Signaling Pathways

PubMed Central

Clarke, Douglas N.; Al Ahmad, Abraham; Lee, Boyeon; Parham, Christi; Auckland, Lisa; Fertala, Andrezj; Kahle, Michael; Shaw, Courtney S.; Roberts, Jill; Bix, Gregory J.

2012-01-01

Perlecan Domain V (DV) promotes brain angiogenesis by inducing VEGF release from brain endothelial cells (BECs) following stroke. In this study, we define the specific mechanism of DV interaction with the α5β1 integrin, identify the downstream signal transduction pathway, and further investigate the functional significance of resultant VEGF release. Interestingly, we found that the LG3 portion of DV, which has been suggested to possess most of DV’s angio-modulatory activity outside of the brain, binds poorly to α5β1 and induces less BEC proliferation compared to full length DV. Additionally, we implicate DV’s DGR sequence as an important element for the interaction of DV with α5β1. Furthermore, we investigated the importance of AKT and ERK signaling in DV-induced VEGF expression and secretion. We show that DV increases the phosphorylation of ERK, which leads to subsequent activation and stabilization of eIF4E and HIF-1α. Inhibition of ERK activity by U0126 suppressed DV-induced expression and secretion of VEGR in BECs. While DV was capable of phosphorylating AKT we show that AKT phosphorylation does not play a role in DV’s induction of VEGF expression or secretion using two separate inhibitors, LY294002 and Akt IV. Lastly, we demonstrate that VEGF activity is critical for DV increases in BEC proliferation, as well as angiogenesis in a BEC-neuronal co-culture system. Collectively, our findings expand our understanding of DV’s mechanism of action on BECs, and further support its potential as a novel stroke therapy. PMID:23028886

Modified model of VX2 tumor overexpressing vascular endothelial growth factor.

PubMed

Pascale, Florentina; Ghegediban, Saida-Homayra; Bonneau, Michel; Bedouet, Laurent; Namur, Julien; Verret, Valentin; Schwartz-Cornil, Isabelle; Wassef, Michel; Laurent, Alexandre

2012-06-01

To determine whether upregulated expression of vascular endothelial growth factor (VEGF) in VX2 cells can increase vessel density (VD) and reduce tumor necrosis. The VX2 cell line was transfected with expression vectors containing cDNA for rabbit VEGF. Stable clones producing rabbit VEGF (VEGF-VX2) were selected. VEGF-VX2 cells (n = 5 rabbits) or nontransfected VX2 cells (controls; n = 5 rabbits) were implanted into leg muscle of 10 rabbits. The animals were sacrificed at day 21. Tumor volume, percentage of necrosis, VD, and VEGF concentration in tumor protein extract were quantified. Overexpression of VEGF by VX2 cells augmented tumor implantation efficiency 100% and favored cyst formation. The tumor volume was significantly larger for VEGF-VX2 transfected tumors versus controls (P = .0143). Overexpression of VEGF in VX2 cells significantly increased the VD of the tumors (P = .0138). The percentage of necrosis was reduced in VEGF-VX2 tumors versus controls (19.5% vs 38.5 %; P = .002). VEGF concentration in VEGF-VX2 tumors was significantly higher than in control tumors (P = .041) and was correlated with tumor volume (ρ = .883, P = .012). The overexpression of VEGF increased tumor growth and vascularization, favored cyst formation, and reduced tumor necrosis. This new phenotype of the VX2 tumor may offer some advantages over classic models of VX2 tumor for evaluating anticancer therapies. Copyright © 2012 SIR. Published by Elsevier Inc. All rights reserved.

Expression pattern of vascular endothelial growth factor 2 during sea urchin development.

PubMed

Kipryushina, Yulia O; Yakovlev, Konstantin V; Kulakova, Milana A; Odintsova, Nelly A

2013-12-01

The VEGF family in the sea urchin is comprised of three members designated Vegf1 through Vegf3. In this study, we found a high level of similarity between the PDGF/VEGF domain of the predicted gene Sp-Vegf2 in the sea urchin Strongylocentrotus purpuratus and the same domain of a gene that we found in a closely related sea urchin, Strongylocentrotus intermedius. The sequence of the Si-Vegf2 cDNA was determined, and the expression of the Si-Vegf2 mRNA throughout early sea urchin development was studied by RT-PCR and in situ hybridization. Also we analyzed phylogenetic relationships of Si-Vegf2 and other members of the PDGF and VEGF families. We have found that the Si-Vegf2 present during the time span from the egg to the 4-arm pluteus stage. This mRNA is uniformly distributed in eggs, cleaving embryos and early blastulae. At the gastrula stage, the Si-Vegf2 transcripts are localized in the ventrolateral clusters of primary mesenchyme cells, and later, at the prism stage, they are detected in the forming apex. At the early pluteus stage, Si-Vegf2 mRNAs are found in two groups of mesenchyme cells in the scheitel region on the apical pole. We have determined that Si-Vegf2 is a mesenchyme-expressed factor but its developmental function is unknown. Copyright © 2013 Elsevier B.V. All rights reserved.

Levels of hormones and cytokines associated with growth in Honamlı and native hair goats.

PubMed

Devrim, A K; Elmaz, O; Mamak, N; Sudagidan, M

2015-01-01

This study was designed to assess alterations of hormone and cytokine levels associated with growth period during puberty in Honamlı goats which were identified as a new goat breed and had one of the highest meat production potential among the other goat breeds in Turkey. Honamlı goats are originated from native hair goats, so parallel studies of sampling and analyzing were conducted also in native hair goats which have moderate meat production. Blood serum samples of Honamlı (n=90) and native hair goats (n=90) were obtained from the pure herds in Korkuteli and Ka districts of Anatolia. Concentrations of growth hormone (GH), myostatin (MSTN), insulin-like growth factor (IGF), growth hormone releasing hormone (GHRH), growth hormone releasing peptide (GHRP), leptin, transforming growth factor-betal (TGF-β1) and vascular endothelial cell growth factor (VEGF) levels were measured by ELISA in each breed in the age groups of 4, 8 and 12 months. The present results indicate interesting correlations among the age groups and all the examined hormone and cytokine parameters exhibited significant (P<0.05 and P<0.001) differences. The parameters investigated were usually begun to increase after 4 months of age in the both breeds and sexes. Therefore, this paper supported the view that the beginning of hormonal alterations of goats could occur at 4th month of age. The results reported here emphasize the primary role played by GH, MSTN, IGF-1, leptin, GHRH, GHRP, TGF-βi and VEGF in the first year growth period of goats.

Signal transduction by VEGF receptors in regulation of angiogenesis and lymphangiogenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shibuya, Masabumi; Claesson-Welsh, Lena

2006-03-10

The VEGF/VPF (vascular endothelial growth factor/vascular permeability factor) ligands and receptors are crucial regulators of vasculogenesis, angiogenesis, lymphangiogenesis and vascular permeability in vertebrates. VEGF-A, the prototype VEGF ligand, binds and activates two tyrosine kinase receptors: VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). VEGFR1, which occurs in transmembrane and soluble forms, negatively regulates vasculogenesis and angiogenesis during early embryogenesis, but it also acts as a positive regulator of angiogenesis and inflammatory responses, playing a role in several human diseases such as rheumatoid arthritis and cancer. The soluble VEGFR1 is overexpressed in placenta in preeclampsia patients. VEGFR2 has critical functions in physiological and pathologicalmore » angiogenesis through distinct signal transduction pathways regulating proliferation and migration of endothelial cells. VEGFR3, a receptor for the lymphatic growth factors VEGF-C and VEGF-D, but not for VEGF-A, regulates vascular and lymphatic endothelial cell function during embryogenesis. Loss-of-function variants of VEGFR3 have been identified in lymphedema. Formation of tumor lymphatics may be stimulated by tumor-produced VEGF-C, allowing increased spread of tumor metastases through the lymphatics. Mapping the signaling system of these important receptors may provide the knowledge necessary to suppress specific signaling pathways in major human diseases.« less

The role of molecular pain biomarkers in temporomandibular joint internal derangement.

PubMed

Ernberg, M

2017-06-01

There is evidence that low-grade inflammation may be responsible for pain and development of degenerative changes in temporomandibular joint internal derangement. This article reviews the current knowledge of the molecular mechanisms behind TMJ internal derangements. A non-systematic search was carried out in PubMed, Embase and the Cochrane library for studies regarding pathophysiological mechanisms behind internal derangements focusing on pain-mediating inflammatory and cartilage-degrading molecules. Recent data suggest that release of cytokines may be the key event for pain and cartilage destruction in TMJ internal derangements. Cytokines promote the release of matrix metalloproteinases (MMPs), and due to hypoxia, vascular endothelial growth factor (VEGF) is released. This activates chondrocytes to produce MMPs and reduce their tissue inhibitors (TIMPs) as well as the recruitment of osteoclasts, ultimately leading to cartilage and bone resorption. Also, proteoglycans have an important role in this process. Several cytokines, MMPs, TIMPs and VEGF have been identified in higher concentrations in the TMJ synovial fluid of patients with painful internal derangements and shown to be associated with the degree of degeneration. Other molecules that show elevated levels include hyaluronic acid synthase, disintegrin and metalloproteinase with thrombospondin motifs (ADAMTs), aggrecan, fibromodulin, biglycan and lumican. Taken together, more or less pronounced inflammation of TMJ structures with release of cytokines, MMPs and other molecular markers that interact in a complex manner may be responsible for tissue degeneration in internal derangements. As internal derangements may be symptom-free, the degree of inflammation, but also other mechanisms, may be important for pain development. © 2017 John Wiley & Sons Ltd.

Endocrine gland-derived endothelial growth factor (EG-VEGF) is a potential novel regulator of human parturition.

PubMed

Dunand, C; Hoffmann, P; Sapin, V; Blanchon, L; Salomon, A; Sergent, F; Benharouga, M; Sabra, S; Guibourdenche, J; Lye, S J; Feige, J J; Alfaidy, N

2014-09-01

EG-VEGF is an angiogenic factor that we identified as a new placental growth factor during human pregnancy. EG-VEGF is also expressed in the mouse fetal membrane (FM) by the end of gestation, suggesting a local role for this protein in the mechanism of parturition. However, injection of EG-VEGF to gravid mice did not induce labor, suggesting a different role for EG-VEGF in parturition. Here, we searched for its role in the FM in relation to human parturition. Human pregnant sera and total FM, chorion, and amnion were collected during the second and third trimesters from preterm no labor, term no labor, and term labor patients. Primary human chorion trophoblast and FM explants cultures were also used. We demonstrate that circulating EG-VEGF increased toward term and significantly decreased at the time of labor. EG-VEGF production was higher in the FM compared to placentas matched for gestational age. Within the FM, the chorion was the main source of EG-VEGF. EG-VEGF receptors, PROKR1 and PROKR2, were differentially expressed within the FM with increased expression toward term and an abrupt decrease with the onset of labor. In chorion trophoblast and FM explants collected from nonlaboring patients, EG-VEGF decreased metalloproteinase-2 and -9 activities and increased PGDH (prostaglandin-metabolizing enzyme) expression. Altogether these data demonstrate that EG-VEGF is a new cytokine that acts locally to ensure FM protection in late pregnancy. Its fine contribution to the initiation of human labor is exhibited by the abrupt decrease in its levels as well as a reduction in its receptors. © 2014 by the Society for the Study of Reproduction, Inc.

The immunohistochemical expression of endocrine gland-derived-VEGF (EG-VEGF) as a prognostic marker in ovarian cancer.

PubMed

Bălu, Sevilla; Pirtea, L; Gaje, Puşa; Cîmpean, Anca Maria; Raica, M

2012-01-01

Ovarian cancer-related angiogenesis is a complex process orchestrated by many positive and negative regulators. Many growth factors are involved in the development of the tumor-associated vasculature, and from these, endocrine gland-derived vascular endothelial growth factor (EG-VEGF) seems to play a crucial role. EG-VEGF is the first organ-specific angiogenic factor and its effects are restricted to the endothelial cells of the endocrine glands. Although EG-VEGF was detected in both normal and neoplastic ovaries, its clinical significance remains controversial. In the present study, we analyzed 30 patients with epithelial ovarian cancer, and the immunohistochemical expression of EG-VEGF was compared with the conventional clinico-pathological parameters of prognosis. Neoplastic cells of the ovarian carcinoma expressed EG-VEGF in 73.33% of the cases, as a cytoplasmic granular product of reaction. We found a strong correlation between the expression of EG-VEGF at protein level and tumor stage, grade, and microscopic type. The expression of EG-VEGF was found in patients with stage III and IV, but not in stage II. The majority of serous adenocarcinoma, half of the cases with clear cell carcinoma and two cases with endometrioid carcinoma showed definite expression in tumor cells. No positive reaction was found in the cases with mucinous carcinoma. Our results showed that EG-VEGF expression is an indicator not only of the advanced stage, but also of ovarian cancer progression. Based on these data, we concluded that EG-VEGF expression in tumor cells of the epithelial ovarian cancer is a good marker of unfavorable prognosis and could be an attractive therapeutic target in patients with advanced-stage tumors, refractory conventional chemotherapy.

Maternal/newborn VEGF-C936T interaction and its influence on the risk, severity and prognosis of preeclampsia, as well as on the maternal angiogenic profile.

PubMed

Procopciuc, Lucia Maria; Caracostea, Gabriela; Zaharie, Gabriela; Stamatian, Florin

2014-11-01

To analyze the influence of maternal/newborn vascular endothelial growth factor (VEGF)-CT936 interaction as a modulating factor in preeclampsia as well as its influence on the maternal angiogenic balance. Seventy pairs of preeclamptic women/newborns and 94 pairs of normal pregnant mothers/newborns were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Serum VEGF and soluble VEGF receptor-1 (sVEGFR-1) levels were measured using ELISA. The risk to develop mild (odds ratio; OR: 3.79, p = 0.008) and severe (OR: 2.94, p = 0.037) preeclampsia being increased in association with the CT936-VEGF genotype and increased in severe preeclampsia to 6.07 (p = 0.03) if the women were carriers of the homozygous TT936-VEGF genotype. The presence of the VEGF-T936 allele in both the mother and the newborn significantly increases the risk of pregnancy-induced hypertension (PIH), mild and severe preeclampsia. If both the mothers and newborns were carriers of the VEGF-T936 allele, significantly lower VEGF and higher sVEGFR-1 levels were observed for all types of preeclampsia. Pregnant women with PIH and severe preeclampsia delivered at a significantly earlier gestational age neonates with a significantly lower birth weight if both the preeclamptic mothers and their newborns were carriers of the VEGF-T936 allele. Our study suggests the role of maternal/fetal VEGF-CT936 polymorphism as a modulating factor in preeclampsia, which affects the angiogenic balance in preeclamptic mothers, as well as their pregnancy outcome.

Anti-Tumor Activity of a Novel HS-Mimetic-Vascular Endothelial Growth Factor Binding Small Molecule

PubMed Central

Sugahara, Kazuyuki; Thimmaiah, Kuntebommanahalli N.; Bid, Hemant K.; Houghton, Peter J.; Rangappa, Kanchugarakoppal S.

2012-01-01

The angiogenic process is controlled by variety of factors of which the vascular endothelial growth factor (VEGF) pathway plays a major role. A series of heparan sulfate mimetic small molecules targeting VEGF/VEGFR pathway has been synthesized. Among them, compound 8 (2-butyl-5-chloro-3-(4-nitro-benzyl)-3H-imidazole-4-carbaldehyde) was identified as a significant binding molecule for the heparin-binding domain of VEGF, determined by high-throughput-surface plasmon resonance assay. The data predicted strong binding of compound 8 with VEGF which may prevent the binding of VEGF to its receptor. We compared the structure of compound 8 with heparan sulfate (HS), which have in common the functional ionic groups such as sulfate, nitro and carbaldehyde that can be located in similar positions of the disaccharide structure of HS. Molecular docking studies predicted that compound 8 binds at the heparin binding domain of VEGF through strong hydrogen bonding with Lys-30 and Gln-20 amino acid residues, and consistent with the prediction, compound 8 inhibited binding of VEGF to immobilized heparin. In vitro studies showed that compound 8 inhibits the VEGF-induced proliferation migration and tube formation of mouse vascular endothelial cells, and finally the invasion of a murine osteosarcoma cell line (LM8G7) which secrets high levels of VEGF. In vivo, these effects produce significant decrease of tumor burden in an experimental model of liver metastasis. Collectively, these data indicate that compound 8 may prevent tumor growth through a direct effect on tumor cell proliferation and by inhibition of endothelial cell migration and angiogenesis mediated by VEGF. In conclusion, compound 8 may normalize the tumor vasculature and microenvironment in tumors probably by inhibiting the binding of VEGF to its receptor. PMID:22916091

Peripheral blood mononuclear cells from patients with rheumatoid arthritis spontaneously secrete vascular endothelial growth factor (VEGF): specific up-regulation by tumour necrosis factor-alpha (TNF-α) in synovial fluid

PubMed Central

BOTTOMLEY, MJ; WEBB, NJA; WATSON, CJ; HOLT, PJL; FREEMONT, AJ; BRENCHLEY, PEC

1999-01-01

This study was designed to investigate VEGF production from peripheral blood mononuclear cells (PBMC) from patients with rheumatoid arthritis (RA) compared with healthy controls and to identify the predominant cellular source in PBMC isolated from RA patients. The regulation of PBMC VEGF production by cytokines and synovial fluid (SF) was studied. PBMC were isolated from RA patients and healthy controls and stimulated with lipopolysaccharide (LPS), IL-1β, IL-4, IL-6, IL-8, IL-10, TNF-α and transforming growth factor-beta (TGF-β) isoforms for varying time points up to 72 h at 37°C/5% CO2. The effect of SF on VEGF secretion by PBMC was also studied. Supernatant VEGF levels were measured using a flt-1 receptor capture ELISA. RA patients had significantly higher spontaneous production of VEGF compared with controls, and monocytes were identified as the predominant cellular source. RA PBMC VEGF production was up-regulated by TGF-β isoforms and TNF-α and down-regulated by IL-4 and IL-10, with no effect observed with IL-1β, IL-6 and IL-8. Antibody blocking experiments confirmed that TNF-α and not TGF-β isoforms in SF increased VEGF secretion by RA PBMC. These results emphasize the importance of monocytes as a source of VEGF in the pathophysiology of RA. Several cytokines known to be present in SF can modulate the level of VEGF secretion, but the predominant effect of SF in VEGF up-regulation is shown to be dependent on TNF-α. PMID:10403932

Vascular endothelial growth factor A (VEGF-A) decreases expression and secretion of pleiotrophin in a VEGF receptor-independent manner.

PubMed

Poimenidi, Evangelia; Theodoropoulou, Christina; Koutsioumpa, Marina; Skondra, Lamprini; Droggiti, Eirini; van den Broek, Marloes; Koolwijk, Pieter; Papadimitriou, Evangelia

2016-05-01

Vascular endothelial growth factor A (VEGF-A) is a key molecule in angiogenesis acting through VEGF receptors (VEGFRs), ανβ3 integrin, receptor protein tyrosine phosphatase beta/zeta (RPTPβ/ζ) and cell surface nucleolin (NCL). Pleiotrophin (PTN) stimulates endothelial cell migration and limits the angiogenic effects of VEGF-A165 to the levels of its own effect, possibly acting as a VEGF-A165 modifier. Since PTN and VEGF-A165 share receptors and actions on endothelial cells, in the present work we studied whether and how VEGF-A165 affects PTN expression or secretion. VEGF-A165 decreased PTN mRNA and protein levels acting at the transcriptional level. Bevacizumab, a selective VEGFR2 tyrosine kinase inhibitor and down-regulation of VEGFR2 expression by siRNA did not affect this decrease, suggesting that it is VEGFR-independent. VEGF-A121 also decreased PTN mRNA and protein levels, suggesting that heparin binding of VEGF-A165 is not involved. Blockage of cell surface NCL, lack of expression or mutation of β3 integrin and down-regulation of RPTPβ/ζ abolished the inhibitory effect of VEGF-A165 on PTN expression and secretion. Down-regulation of endogenous PTN in endothelial cells enhanced VEGF-A165-induced increase in migration and tube formation on matrigel. Collectively, these data suggest that VEGF-A down-regulates PTN expression and secretion through the RPTPβ/ζ-ανβ3-NCL axis to enhance its own effect on cell migration and further highlight the role of RPTPβ/ζ in VEGF-A actions. Copyright © 2016 Elsevier Inc. All rights reserved.

Cytokines and bullous pemphigoid.

PubMed

D'Auria, L; Cordiali Fei, P; Ameglio, F

1999-06-01

This report reviews the data presented in the literature concerning the presence and levels of different cytokines in sera, lesional tissue or blister fluids of patients with bullous pemphigoid. The list of cytokines analysed includes 21 molecules: interleukins (IL)-1 => 8, IL-10 => 13, IL-15, granulocyte-monocyte-colony stimulating factor (GM-CSF), interferon-gamma (IFN-gamma), oncostatin-M (OSM), regulated upon activation normal T cell expressed and presumably secreted (RANTES), transforming growth factor-beta 1 (TGF-beta 1), tumor necrosis factor-alpha (TNF-alpha) and vascular endothelial growth factor (VEGF). Basic information regarding the functions of these cytokines and their possible involvement in the pathogenetic steps of the disease, such as autoantigen expression, autoantibody induction, complement activation, local cell recruitment and stimulation, resident cell activation, release of various effector molecules and tissue damage are also reported. A specific function for each cytokine in bullous pemphigoid induction cannot be still defined, however, the literature attributes a major role to IL-1, IL-4, IL-5, IL-6, IL-8 and IFN-gamma. On the basis of significant (direct or inverse) correlations found between disease intensity and the blister fluid/serum levels, the following cytokines IL-7, IL-15, RANTES, VEGF and TNF-alpha, besides those previously mentioned, may also be involved in this disease.

Enhanced Mitogenic Activity of Recombinant Human Vascular Endothelial Growth Factor VEGF121 Expressed in E. coli Origami B (DE3) with Molecular Chaperones.

PubMed

Kaplan, Ondřej; Zárubová, Jana; Mikulová, Barbora; Filová, Elena; Bártová, Jiřina; Bačáková, Lucie; Brynda, Eduard

2016-01-01

We describe the production of a highly-active mutant VEGF variant, α2-PI1-8-VEGF121, which contains a substrate sequence for factor XIIIa at the aminoterminus designed for incorporation into a fibrin gel. The α2-PI1-8-VEGF121 gene was synthesized, cloned into a pET-32a(+) vector and expressed in Escherichia coli Origami B (DE3) host cells. To increase the protein folding and the solubility, the resulting thioredoxin-α2-PI1-8-VEGF121 fusion protein was co-expressed with recombinant molecular chaperones GroES/EL encoded by independent plasmid pGro7. The fusion protein was purified from the soluble fraction of cytoplasmic proteins using affinity chromatography. After cleavage of the thioredoxin fusion part with thrombin, the target protein was purified by a second round of affinity chromatography. The yield of purified α2-PI1-8-VEGF121 was 1.4 mg per liter of the cell culture. The α2-PI1-8-VEGF121 expressed in this work increased the proliferation of endothelial cells 3.9-8.7 times in comparison with commercially-available recombinant VEGF121. This very high mitogenic activity may be caused by co-expression of the growth factor with molecular chaperones not previously used in VEGF production. At the same time, α2-PI1-8-VEGF121 did not elicit considerable inflammatory activation of human endothelial HUVEC cells and human monocyte-like THP-1 cells.

Imatinib mesylate (STI571) decreases the vascular endothelial growth factor plasma concentration in patients with chronic myeloid leukemia.

PubMed

Legros, Laurence; Bourcier, Christine; Jacquel, Arnaud; Mahon, François-Xavier; Cassuto, Jill-Patrice; Auberger, Patrick; Pagès, Gilles

2004-07-15

Increased angiogenesis in bone marrow (BM) is one of the characteristics of chronic myeloid leukemia (CML), a clonal myeloproliferative disorder that expresses a chimeric Bcr/Abl protein. Recently, the therapeutic strategy in CML has been totally modified with the development of a new drug: imatinib mesylate (STI571), a specific inhibitor of Bcr/Abl tyrosine kinase activity. The aim of our study was to determine, in patients with CML, the capacity of imatinib mesylate to modulate one of the most potent regulators of angiogenesis, the vascular endothelial growth factor (VEGF). In newly diagnosed CML, we observed significantly increased VEGF secretion by CML BM cells and significantly increased VEGF plasma concentrations. We showed that low plasma VEGF concentrations could be one of the characteristics of complete cytogenetic remission. To understand the molecular mechanisms leading to the inhibition of VEGF production by imatinib, we focused our experiments on the human cell line K562, which is Bcr/Abl positive. We demonstrated that imatinib inhibits VEGF gene transcription by targeting the Sp1 and Sp3 transcription factors. Taken together, our results highlight the potential prognostic value of VEGF concentrations in evaluating the evolution of CML patients treated with imatinib.

Vascular endothelial growth factor (VEGF-634G/C) polymorphism and retinopathy of prematurity: a meta-analysis

PubMed Central

Malik, Manzoor Ahmad; Shukla, Swati; Azad, Shorya Vardhan; Kaur, Jasbir

2014-01-01

Purpose Vascular endothelial growth factor polymorphism (VEGF-634G/C, rs 2010963) has been considered a risk factor for the development of retinopathy of prematurity (ROP). However, the results remain controversial. Therefore, the aim of the present meta-analysis was to determine the association between VEGF-634G/C polymorphism and ROP risk. Methods Published literature from PubMed and other databases were retrieved. All studies evaluating the association between VEGF-634G/C polymorphism and ROP risk were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using random or fixed effects model. A total of six case-control studies including 355 cases and 471 controls were included. Results By pooling all the studies, we found that VEGF-634G/C polymorphism was not associated with ROP risk at co-dominant and allele levels and no association was also found in dominant and recessive models. While stratifying on ethnicity level no association was observed in Caucasian and Asian population. Discussion This meta-analysis suggests that VEGF-634G/C polymorphism may not be associated with ROP risk, the association between single VEGF-634G/C polymorphism and ROP risk awaits further investigation. PMID:25473347

Essential roles of angiotensin II in vascular endothelial growth factor expression in sleep apnea syndrome.

PubMed

Takahashi, Susumu; Nakamura, Yutaka; Nishijima, Tsuguo; Sakurai, Shigeru; Inoue, Hiroshi

2005-09-01

Hypoxia-induced endothelial cell dysfunction has been implicated in increased cardiovascular disease associated with obstructive sleep apnea syndrome (OSAS). OSAS mediates hypertension by stimulating angiotensin II (Ang II) production. Hypoxia and Ang II are the major stimuli of vascular endothelial growth factor (VEGF), which is a potent angiogenic cytokine and also contributes to the atherogenic process itself. We observed serum Ang II and VEGF levels and peripheral blood mononuclear cell (PBMC) and neutrophil VEGF expression. Compared to controls, subjects with OSAS had significantly increased levels of serum Ang II and VEGF and VEGF mRNA expression in their leukocytes. To examine whether Ang II stimulates VEGF expression in OSAS, we treated PBMCs obtained from control subjects with Ang II and with an Ang II receptor type 1 (AT(1)) blocker, olmesartan. We observed an increased expression of VEGF in the Ang II-stimulated PBMCs and decreased in VEGF mRNA and protein expression in the PBMCs treated with olmesartan. These findings suggest that the Ang II-AT(1) receptors pathway potentially are involved in OSAS and VEGF-induced vascularity and that endothelial dysfunction might be linked to this change in Ang II activity within leukocytes of OSAS patients.

Nuclear translocation of phosphorylated STAT3 regulates VEGF-A-induced lymphatic endothelial cell migration and tube formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okazaki, Hideki; Tokumaru, Sho; Hanakawa, Yasushi

2011-09-02

Highlights: {yields} VEGF-A enhanced lymphatic endothelial cell migration and increased tube formation. {yields} VEGF-A treated lymphatic endothelial cell showed activation of STAT3. {yields} Dominant-negative STAT3 inhibited VEGF-A-induced lymphatic endothelial cell migration and tube formation. -- Abstract: Vascular endothelial growth factor (VEGF) is an endothelial cell-specific growth factor that regulates endothelial functions, and signal transducers and activators of transcription (STATs) are known to be important during VEGF receptor signaling. The aim of this study was to determine whether STAT3 regulates VEGF-induced lymphatic endothelial cell (LEC) migration and tube formation. VEGF-A (33 ng/ml) enhanced LEC migration by 2-fold and increased tube lengthmore » by 25% compared with the control, as analyzed using a Boyden chamber and Matrigel assay, respectively. Western blot analysis and immunostaining revealed that VEGF-A induced the nuclear translocation of phosphorylated STAT3 in LECs, and this translocation was blocked by the transfection of LECs with an adenovirus vector expressing a dominant-negative mutant of STAT3 (Ax-STAT3F). Transfection with Ax-STAT3F also almost completely inhibited VEGF-A-induced LEC migration and tube formation. These results indicate that STAT3 is essential for VEGF-A-induced LEC migration and tube formation and that STAT3 regulates LEC functions.« less

Enhanced effect of VEGF165 on L-type calcium currents in guinea-pig cardiac ventricular myocytes.

PubMed

Xing, Wenlu; Gao, Chuanyu; Qi, Datun; Zhang, You; Hao, Peiyuan; Dai, Guoyou; Yan, Ganxin

2017-01-01

The mechanisms of vascular endothelial growth factor 165 (VEGF165) on electrical properties of cardiomyocytes have not been fully elucidated. The aim of this study is to test the hypothesis that VEGF165, an angiogenesis-initiating factor, affects L-type calcium currents (I Ca,L ) and cell membrane potential in cardiac myocytes by acting on VEGF type-2 receptors (VEGFR2). I Ca,L and action potentials (AP) were recorded by the whole-cell patch clamp method in isolated guinea-pig ventricular myocytes treated with different concentrations of VEGF165 proteins. Using a VEGFR2 inhibitor, we also tested the receptor of VEGF165 in cardiomyocytes. We found that VEGF165 increased I Ca,L in a concentration-dependent manner. SU5416, a VEGFR2 inhibitor, almost completely eliminated VEGF165-induced I Ca,L increase. VEGF165 had no significant influence on action potential 90 (APD90) and other properties of AP. We conclude that in guinea-pig ventricular myocytes, I Ca,L can be increased by VEGF165 in a concentration-dependent manner through binding to VEGFR2 without causing any significant alteration to action potential duration. Results of this study may further expound the safety of VEGF165 when used in the intervention of heart diseases. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Spider angiomas in patients with liver cirrhosis: Role of vascular endothelial growth factor and basic fibroblast growth factor

PubMed Central

Li, Chung-Pin; Lee, Fa-Yauh; Hwang, Shinn-Jang; Lu, Rei-Hwa; Lee, Wei-Ping; Chao, Yee; Wang, Sung-Sang; Chang, Full-Young; Whang-Peng, Jacqueline; Lee, Shou-Dong

2003-01-01

AIM: To investigate whether vascular endothelial growth factor (VEGF) and basic fibroblastic growth factor (bFGF) are associated with spider angiomas in patients with liver cirrhosis. METHODS: Eighty-six patients with liver cirrhosis were enrolled and the number and size of the spider angiomas were recorded. Fifty-three healthy subjects were selected as controls. Plasma levels of VEGF and bFGF were measured in both the cirrhotics and the controls. RESULTS: Plasma VEGF and bFGF were increased in cirrhotics compared with controls (122 ± 13 vs. 71 ± 11 pg/mL, P = 0.003 for VEGF; 5.1 ± 0.5 vs. 3.4 ± 0.5 pg/mL, P = 0.022 for bFGF). In cirrhotics, plasma VEGF and bFGF were also higher in patients with spider angiomas compared with patients without spider angiomas (185 ± 28 vs. 90 ± 10 pg/mL, P = 0.003 for VEGF; 6.8 ± 1.0 vs. 4.1 ± 0.5 pg/mL, P = 0.017 for bFGF). Multivariate logistic regression showed that young age and increased plasma levels of VEGF and bFGF were the most significant predictors for the presence of spider angiomas in cirrhotic patients (odds ratio [OR] = 6.64, 95% confidence interval [CI] = 2.02-21.79, P = 0.002; OR = 4.35, 95%CI = 1.35-14.01, P = 0.014; OR = 5.66, 95%CI = 1.72-18.63, P = 0.004, respectively). CONCLUSION: Plasma VEGF and bFGF are elevated in patients with liver cirrhosis. Age as well as plasma levels of VEGF and bFGF are significant predictors for spider angiomas in cirrhotic patients. PMID:14669345

Circulating plasma vascular endothelial growth factor and microvascular complications of type 1 diabetes mellitus: the influence of ACE inhibition.

PubMed

Chaturvedi, N; Fuller, J H; Pokras, F; Rottiers, R; Papazoglou, N; Aiello, L P

2001-04-01

To determine whether circulating plasma vascular endothelial growth factor (VEGF) is elevated in the presence of diabetic microvascular complications, and whether the impact of angiotensin-converting enzyme (ACE) inhibitors on these complications can be accounted for by changes in circulating VEGF. Samples (299/354 of those with retinal photographs) from the EUCLID placebo-controlled clinical trial of the ACE inhibitor lisinopril in mainly normoalbuminuric non-hypertensive Type 1 diabetic patients were used. Albumin excretion rate (AER) was measured 6 monthly. Geometric mean VEGF levels by baseline retinopathy status, change in retinopathy over 2 years, and by treatment with lisinopril were calculated. No significant correlation was observed between VEGF at baseline and age, diabetes duration, glycaemic control, blood pressure, smoking, fibrinogen and von Willebrand factor. Mean VEGF concentration at baseline was 11.5 (95% confidence interval 6.0--27.9) pg/ml in those without retinopathy, 12.9 (6.0--38.9) pg/ml in those with non-proliferative retinopathy, and 16.1 (8.1--33.5) pg/ml in those with proliferative retinopathy (P = 0.06 for trend). Baseline VEGF was 15.2 pg/ml in those who progressed by at least one level of retinopathy by 2 years compared to 11.8 pg/ml in those who did not (P = 0.3). VEGF levels were not altered by lisinopril treatment. Results were similar for AER. Circulating plasma VEGF concentration is not strongly correlated with risk factor status or microvascular disease in Type 1 diabetes, nor is it affected by ACE inhibition. Changes in circulating VEGF cannot account for the beneficial effect of ACE inhibition on retinopathy.

Luteogenic Hormones Act through a Vascular Endothelial Growth Factor-Dependent Mechanism to Up-Regulate α5β1 and αvβ3 Integrins, Promoting the Migration and Survival of Human Luteinized Granulosa Cells

PubMed Central

Rolaki, Alexandra; Coukos, George; Loutradis, Dimitris; DeLisser, Horace M.; Coutifaris, Christos; Makrigiannakis, Antonis

2007-01-01

The formation of the corpus luteum (CL) is critical for the establishment of a successful pregnancy. After ovulation, the CL develops from the remnants of the ovulated ovarian follicle. This process, which involves varying cell-matrix interactions, is poorly characterized. To understand the role and potential regulation of cell-matrix interactions in the formation of the CL, we investigated the expression and activity of the matrix protein fibronectin (FN) and several of its integrin receptors on luteinized granulosa cells (GCs). In situ, FN and several FN-binding integrins were detected around luteinizing GCs during the early luteal phase, although expression declined in the late luteal phase. In vitro, GCs released FN, and stimulation of these cells with human chorionic gonadotropin increased the surface expression of FN, α5β1, and αvβ3. Up-regulation of these proteins on GCs was reproduced by stimulation with vascular endothelial growth factor (VEGF) and was inhibited by anti-VEGF antibody. Lastly, expression of α5β1 and αvβ3 mediated adhesion to FN, facilitated migration, and prevented apoptosis. These data suggest that in vivo luteogenic hormones, in part through a VEGF-dependent mechanism, stimulate selected integrin-matrix adhesive interactions that promote the motility and survival of GCs and thus contribute to the formation and preservation of the CL. PMID:17456762

Asbestos and erionite prime and activate the NLRP3 inflammasome that stimulates autocrine cytokine release in human mesothelial cells

PubMed Central

2013-01-01

Background Pleural fibrosis and malignant mesotheliomas (MM) occur after exposures to pathogenic fibers, yet the mechanisms initiating these diseases are unclear. Results We document priming and activation of the NLRP3 inflammasome in human mesothelial cells by asbestos and erionite that is causally related to release of IL-1β, IL-6, IL-8, and Vascular Endothelial Growth Factor (VEGF). Transcription and release of these proteins are inhibited in vitro using Anakinra, an IL-1 receptor antagonist that reduces these cytokines in a human peritoneal MM mouse xenograft model. Conclusions These novel data show that asbestos-induced priming and activation of the NLRP3 inflammasome triggers an autocrine feedback loop modulated via the IL-1 receptor in mesothelial cell type targeted in pleural infection, fibrosis, and carcinogenesis. PMID:23937860

Vascular endothelial growth factor C promotes cervical cancer cell invasiveness via regulation of microRNA-326/cortactin expression.

PubMed

Cheng, Yang; Jiang, Shuyi; Yuan, Jin; Liu, Junxiu; Simoncini, Tommaso

2018-04-16

Vascular endothelial growth factor C (VEGF-C) accelerates cervical cancer metastasis, while the detailed mechanism remains largely unknown. Recent evidence indicates that microRNA play a crucial role in controlling cancer cell invasiveness. In the present study, we investigated the role of miR-326 in VEGF-C-induced cervical cancer cell invasion. VEGF-C expression was higher and miR-326 was much lower in primary cervical cancer specimens than that in non-cancerous specimens, and a negative correlation between VEGF-C and miR-326 was found. On cervical carcinoma cell line SiHa cells, treatment with VEGF-C downregulated miR-326 level and increased cortactin protein expression. Transfection with miR-326 mimic reversed cortactin expression induced by VEGF-C, suggesting that VEGF-C increased cortactin via downregulation of miR-326. VEGF-C activated c-Src and c-Src inhibitor PP2 abolished VEGF-C effect on miR-326 and cortactin expression, implying that VEGF-C regulated miR-326/cortactin via c-Src signaling. VEGF-C promoted SiHa cell invasion index, which was largely inhibited by transfection with miR-326 antagonist or by siRNA against cortactin. In conclusion, our findings implied that VEGF-C reduced miR-326 expression and increased cortactin expression through c-Src signaling, leading to enhanced cervical cancer invasiveness. This may shed light on potential therapeutic strategies for cervical cancer therapy.

Effects of antibodies to EG-VEGF on angiogenesis in the chick embryo chorioallantoic membrane.

PubMed

Feflea, Stefana; Cimpean, Anca Maria; Ceausu, Raluca Amalia; Gaje, Pusa; Raica, Marius

2012-01-01

Endocrine gland-related vascular endothelial growth factor (EG-VEGF), is an angiogenic factor specifically targeting endothelial cells derived from endocrine tissues. The inhibition of the EG-VEGF/prokineticin receptor pathway could represent a selective antiangiogenic and anticancer strategy. to evaluate the impact of an antibody to EG-VEGF on the rapidly growing capillary plexus of the chick embryo chorioallantoic membrane (CAM). The in ovo CAM assay was performed for the humanized EG-VEGF antibody. Hemorrhagic damage was induced in the capillaries, which led to early death of the embryos. Upon morphological staining, there was evidence of vascular disruption and extravasation of red blood cells in the chorion. Signs of vacuolization of the covering epithelium were also observed. Blocking endogenous EG-VEGF might represent a valuable approach of impairing or inhibiting angiogenesis in steroidogenic-derived embryonic tissues.

Vascular Repair After Menstruation Involves Regulation of Vascular Endothelial Growth Factor-Receptor Phosphorylation by sFLT-1

PubMed Central

Graubert, Michael D.; Asuncion Ortega, Maria; Kessel, Bruce; Mortola, Joseph F.; Iruela-Arispe, M. Luisa

2001-01-01

Regeneration of the endometrium after menstruation requires a rapid and highly organized vascular response. Potential regulators of this process include members of the vascular endothelial growth factor (VEGF) family of proteins and their receptors. Although VEGF expression has been detected in the endometrium, the relationship between VEGF production, receptor activation, and endothelial cell proliferation during the endometrial cycle is poorly understood. To better ascertain the relevance of VEGF family members during postmenstrual repair, we have evaluated ligands, receptors, and activity by receptor phosphorylation in human endometrium throughout the menstrual cycle. We found that VEGF is significantly increased at the onset of menstruation, a result of the additive effects of hypoxia, transforming growth factor-α, and interleukin-1β. Both VEGF receptors, FLT-1 and KDR, followed a similar pattern. However, functional activity of KDR, as determined by phosphorylation studies, revealed activation in the late menstrual and early proliferative phases. The degree of KDR phosphorylation was inversely correlated with the presence of sFLT-1. Endothelial cell proliferation analysis in endometrium showed a peak during the late menstrual and early proliferative phases in concert with the presence of VEGF, VEGF receptor phosphorylation, and decrease of sFLT-1. Together, these results suggest that VEGF receptor activation and the subsequent modulation of sFLT-1 in the late menstrual phase likely contributes to the onset of angiogenesis and endothelial repair in the human endometrium. PMID:11290558

Expression of vascular endothelial growth factor in third-trimester placentas is not increased in growth-restricted fetuses.

PubMed

Tse, J Y; Lao, T T; Chan, C C; Chiu, P M; Cheung, A N

2001-01-01

Vascular endothelial growth factor (VEGF) is considered the growth factor that stimulates vasculogenesis and angiogenesis. Recent studies have demonstrated its role in regulating placental growth and invasion. Its expression can be upregulated by hypoxia. Intrauterine growth restriction (IUGR) is thought to be associated with inadequate placental perfusion, which might result from a failure in the development of the villous vascular network. Our present study was undertaken to examine the relationship between VEGF expression and IUGR in pregnancies with preserved umbilical artery end-diastolic flow. VEGF Expression was determined by immunohistochemical analysis of placentas from 17 pregnancies with normal infant birth weight and 17 pregnancies complicated by IUGR. We found no significant differences in the expression of VEGF in villous syncytiotrophoblasts and intermediate trophoblasts in maternal decidua between IUGR and normal pregnancies. However, in both groups there was a strong correlation in the expression of VEGF with villous syncytiotrophoblasts and intermediate trophoblasts. In normal and IUGR pregnancies the infants' Apgar scores at birth were significantly correlated with VEGF staining in both syncytiotrophoblasts and intermediate trophoblasts (P < .05). A strong correlation also was found between cord hematocrit and VEGF staining in villous syncytiotrophoblasts (P < .05), but VEGF staining in intermediate trophoblasts was not correlated with cord hemoglobin or hematocrit. Our results suggest that VEGF acts in an autocrine and paracrine fashion in both normal and IUGR placentas, and its expression can have an effect on the well being of the infant at birth.

[Expression of vascular endothelial growth factor and its significance in pulmonary bronchoalveolar carcinoma].

PubMed

Song, Weian; Li, Hui; Wang, Huasheng; Zhang, Weidong; Zhao, Xiaogang

2004-02-20

To study the relationship between the vascular endothelial growth factor (VEGF) and the clinicopathological characteristics of the patients with pulmonary bronchoalveolar carcinoma, and to research the possible role of VEGF in the malignant growth of pulmonary bronchoalveolar carcinoma. The expression of VEGF and MVD were detected in 38 pulmonary bronchoalveolar carcinoma and 20 normal lung tissues by immunohistochemical method. The positive rate of VEGF expression (73.68%,28/38) and MVD (63.81±19.26) in pulmonary bronchoalveolar carcinoma tissues were both remarkably higher than those in normal lung tissues (0, 18.44±6.53)( P < 0.005,P < 0.001). The positive rate of VEGF expression was significantly related to the size of tumor ( P < 0.05), lymphatic metastasis ( P < 0.025) and TNM stage ( P < 0.05), and so did the MVD ( P < 0.05, P < 0.05, P < 0.05). MVD was remarkably higher in VEGF (+) carcinoma tissues than that in VEGF (-) carcinoma tissues ( P < 0.05). VEGF correlates with the clinicopathological characteristics of pulmonary bronchoalveolar carcinoma. It may play an important role in the development of pulmonary bronchoalveolar carcinoma.

Is There a Relationship Between Use of Anti-Vascular Endothelial Growth Factor Agents and Atrophic Changes in Age-Related Macular Degeneration Patients?

PubMed

Kaynak, Süleyman; Kaya, Mahmut; Kaya, Derya

2018-04-01

Choroidal neovascularization due to age-related macular degeneration (AMD) is currently treated successfully with anti-vascular endothelial growth factor (VEGF) intravitreal agents. Emerging evidence suggests that anti-VEGF treatment may potentially increase development of geographic atrophy. However, there is not yet direct proof of a causal relationship between geographic atrophy and use of anti-VEGF agents in neovaskuler AMD. The aim of this review is to discuss the evidence concerning the association between anti-VEGF therapy and progression of geographic atrophy.

Lack of Obvious Influence of PLLA Nanofibers on the Gene Expression of BMP-2 and VEGF during Growth and Differentiation of Human Mesenchymal Stem Cells

PubMed Central

Schofer, Markus D.; Fuchs-Winkelmann, S.; Wack, C.; Rudisile, M.; Dersch, R.; Leifeld, I.; Wendorff, J.; Greiner, A.; Paletta, J. R. J.; Boudriot, U.

2009-01-01

Growth factors like bone morphogenetic protein 2 (BMP-2) and vascular endothelial growth factor (VEGF) play an important role in bone remodeling and fracture repair. Therefore, with respect to tissue engineering, an artificial graft should have no negative impact on the expression of these factors. In this context, the aim of this study was to analyze the impact of poly(L-lactic acid) (PLLA) nanofibers on VEGF and BMP-2 gene expression during the time course of human mesenchymal stem cell (hMSC) differentiation towards osteoblasts. PLLA matrices were seeded with hMSCs and cultivated over a period of 22 days under growth and osteoinductive conditions, and analyzed during the course of culture, with respect to gene expression of VEGF and BMP-2. Furthermore, BMP-2–enwoven PLLA nanofibers were used in order to elucidate whether initial down-regulation of growth factor expression could be compensated. Although there was a great interpatient variability with respect to the expression of VEGF and BMP-2, PLLA nanofibers tend to result in a down-regulation in BMP-2 expression during the early phase of cultivation. This effect was diminished in the case of VEGF gene expression. The initial down-regulation was overcome when BMP-2 was directly incorporated into the PLLA nanofibers by electrospinning. Furthermore, the incorporation of BMP-2 into the PLLA nanofibers resulted in an increase in VEGF gene expression. Summarized, the results indicate that the PLLA nanofibers have little effect on growth factor production. An enhancement in gene expression of BMP-2 and VEGF can be achieved by an incorporation of BMP-2 into the PLLA nanofibers. PMID:19412560

[Pathogenetic and Prognostic Role of Growth Factors in the Development of Chronic Heart Failure].

PubMed

Teplyakov, A T; Berezikova, E N; Shilov, S N; Efremova, A V; Pustovetova, M G; Popova, A A; Grakova, E V; Torim, Y Y; Safronov, I D; Andriyanova, A V

2017-10-01

To study the role of growth factors ((vascular endothelial growth factor (VEGF), platelet derived growth factor AB (PDGF-AB) and basic fibroblast growth factor (FGF-basic)) in the development and progression of chronic heart failure (CHF) in patients with ishcemic heart disease (IHD). We included in this study 94 patients with CHF. The control group comprised 32 persons. Blood serum levels of growth factors were determined at baseline and after 12 months of observation by enzyme-linked immunosorbent assay. VEGF, PDGF-AB and FGF-basic play an important role in the pathogenesis and progression of heart failure in patients with IHD, determining the increased risk of adverse cardiovascular events in this pathology. Serum activity of growth factors characterizes the severity and course of CHF: with disease progression levels of VEGF and FGF-basic decrease and PDGF-AB concentration increases. Initial low level of VEGF expression regardless of the sex of the patient's sex, significantly low level of FGF-basic and significantly high PDGF-AB in men characterizes unfavorable course of CHF. A correlation has been established between blood serum levels of VEGF, PDGF-AB and FGF-basic and severity and course of CHF.

Ocular Angiogenesis: Vascular Endothelial Growth Factor and Other Factors.

PubMed

Rubio, Roman G; Adamis, Anthony P

2016-01-01

Systematic study of the mechanisms underlying pathological ocular neovascularization has yielded a wealth of knowledge about pro- and anti-angiogenic factors that modulate diseases such as neovascular age-related macular degeneration. The evidence implicating vascular endothelial growth factor (VEGF) in particular has led to the development of a number of approved anti-VEGF therapies. Additional proangiogenic targets that have emerged as potential mediators of ocular neovascularization include hypoxia-inducible factor-1, angiopoietin-2, platelet-derived growth factor-B and components of the alternative complement pathway. As for VEGF, knowledge of these factors has led to a product pipeline of many more novel agents that are in various stages of clinical development in the setting of ocular neovascularization. These agents are represented by a range of drug classes and, in addition to novel small- and large-molecule VEGF inhibitors, include gene therapies, small interfering RNA agents and tyrosine kinase inhibitors. In addition, combination therapy is beginning to emerge as a strategy to improve the efficacy of individual therapies. Thus, a variety of agents, whether administered alone or as adjunctive therapy with agents targeting VEGF, offer the promise of expanding the range of treatments for ocular neovascular diseases. © 2016 S. Karger AG, Basel.

Silencing of VEGF inhibits human osteosarcoma angiogenesis and promotes cell apoptosis via VEGF/PI3K/AKT signaling pathway

PubMed Central

Peng, Ningning; Gao, Shuming; Guo, Xu; Wang, Guangya; Cheng, Cai; Li, Min; Liu, Kehun

2016-01-01

Background: Osteosarcoma is a kind of highly malignant tumor and the growth and metastasis is closely related to angiogenesis. Vascular endothelial growth factor (VEGF) is an important angiogenesis-promoting factor. In the current study, we investigated the effects of suppressed VEGF on osteosarcoma and its molecular mechanism provided for a basis by targeting angiogenesis. Material/Methods: We established bearing human osteosarcoma Wistar rats model by subcutaneous inoculation of human SaOS-2 cells and the adenovirus vector Ad-VEGF-siRNA was constructed for further study. We assessed the efficiency of VEGF silencing and its influence on SaOS-2 cells. The expression of mRNA and protein were detected by RT-PCR and western blotting, respectively. Intratumoral microvessel density (MVD), VEGF and CD31 were evaluated by immunohistochemistry. We detected the cell apoptotic rates by flow cytometry. Results: Our results indicated that Ad-VEGF-siRNA could effectively suppressed the expression of VEGF expression, inhibited the proliferation capability and promoted apoptosis of SaOS-2 cells in vitro. Silencing of VEGF expression also suppress osteosarcoma tumor growth and reduce osteosarcoma angiogenesis in the Wistar rats model in vivo. Furthermore, We found that phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) activation were considerably reduced while inhibition VEGF expression in SaOS-2 cells. Conclusion: Our data demonstrated that VEGF silencing could suppress cells proliferation, promote cells apoptosis and reduce osteosarcoma angiogenesis through inactivation of VEGF/PI3K/AKT signaling pathway. PMID:27158386

Vascular Endothelial Growth Factor Modulates Skeletal Myoblast Function

PubMed Central

Germani, Antonia; Di Carlo, Anna; Mangoni, Antonella; Straino, Stefania; Giacinti, Cristina; Turrini, Paolo; Biglioli, Paolo; Capogrossi, Maurizio C.

2003-01-01

Vascular endothelial growth factor (VEGF) expression is enhanced in ischemic skeletal muscle and is thought to play a key role in the angiogenic response to ischemia. However, it is still unknown whether, in addition to new blood vessel growth, VEGF modulates skeletal muscle cell function. In the present study immunohistochemical analysis showed that, in normoperfused mouse hindlimb, VEGF and its receptors Flk-1 and Flt-1 were expressed mostly in quiescent satellite cells. Unilateral hindlimb ischemia was induced by left femoral artery ligation. At day 3 and day 7 after the induction of ischemia, Flk-1 and Flt-1 were expressed in regenerating muscle fibers and VEGF expression by these fibers was markedly enhanced. Additional in vitro experiments showed that in growing medium both cultured satellite cells and myoblast cell line C2C12 expressed VEGF and its receptors. Under these conditions, Flk-1 receptor exhibited constitutive tyrosine phosphorylation that was increased by VEGF treatment. During myogenic differentiation Flk-1 and Flt-1 were down-regulated. In a modified Boyden Chamber assay, VEGF enhanced C2C12 myoblasts migration approximately fivefold. Moreover, VEGF administration to differentiating C2C12 myoblasts prevented apoptosis, while inhibition of VEGF signaling either with selective VEGF receptor inhibitors (SU1498 and CB676475) or a neutralizing Flk-1 antibody, enhanced cell death approximately 3.5-fold. Finally, adenovirus-mediated VEGF165 gene transfer inhibited ischemia-induced apoptosis in skeletal muscle. These results support a role for VEGF in myoblast migration and survival, and suggest a novel autocrine role of VEGF in skeletal muscle repair during ischemia. PMID:14507649

A Review of the Development of a Vehicle for Localized and Controlled Drug Delivery for Implantable Biosensors

PubMed Central

Bhardwaj, Upkar; Papadimitrakopoulos, Fotios; Burgess, Diane J.

2008-01-01

A major obstacle to the development of implantable biosensors is the foreign body response (FBR) that results from tissue trauma during implantation and the continuous presence of the implant in the body. The in vivo stability and functionality of biosensors are compromised by damage to sensor components and decreased analyte transport to the sensor. This paper summarizes research undertaken by our group since 2001 to control the FBR toward implanted sensors. Localized and sustained delivery of the anti-inflammatory drug, dexamethasone, and the angiogenic growth factor, vascular endothelial growth factor (VEGF), was utilized to inhibit inflammation as well as fibrosis and provide a stable tissue–device interface without producing systemic adverse effects. The drug-loaded polylactic-co-glycolic acid (PLGA) microspheres were embedded in a polyvinyl alcohol (PVA) hydrogel composite to fabricate a drug-eluting, permeable external coating for implantable devices. The composites were fabricated using the freeze–thaw cycle method and had mechanical properties similar to soft body tissue. Dexamethasone-loaded microsphere/hydrogel composites were able to provide anti-inflammatory protection, preventing the FBR. Moreover, concurrent release of dexamethasone with VEGF induced neoangiogenesis in addition to providing anti-inflammatory protection. Sustained release of dexamethasone is required for the entire sensor lifetime, as a delayed inflammatory response developed after depletion of the drug from the composites. These studies have shown the potential of PLGA microsphere/PVA hydrogel-based composites as drug-eluting external coatings for implantable biosensors. PMID:19885291

Prostaglandins induce vascular endothelial growth factor in a human monocytic cell line and rat lungs via cAMP.

PubMed

Höper, M M; Voelkel, N F; Bates, T O; Allard, J D; Horan, M; Shepherd, D; Tuder, R M

1997-12-01

Prostaglandins have emerged as a therapeutic option for patients with peripheral vascular disease as well as pulmonary hypertension as a means to increase blood flow. We tested the hypothesis that prostaglandins regulate vascular endothelial growth factor (VEGF) expression in the human monocytic THP-1 cell line and in isolated perfused rat lungs. Our data show that the stable PGI2-analogue iloprost induces VEGF gene expression (predominantly VEGF121, but also VEGF165 isoforms) and VEGF protein synthesis in THP-1 cells. This effect is abolished by dexamethasone and by Rp-cAMP, a specific inhibitor of cAMP-dependent protein kinase (PKA) activation. The calcium channel blocker diltiazem has no effect on the iloprost-induced VEGF gene expression, and depletion of intracellular Ca2+ stores by long-term exposure (16 h) of THP-1 cells to thapsigargin does not inhibit iloprost-induced VEGF gene expression, suggesting that an increase in intracellular Ca2+ is not essential for VEGF gene induction by iloprost. However, an increase of intracellular Ca2+ by a short-term (2 h) exposure of THP-1 cells to thapsigargin or to the calcium-ionophore A23187 increases VEGF mRNA levels, indicating that a change in intracellular Ca2+ by itself can alter VEGF gene expression. The effects of thapsigargin or A23187 on VEGF gene expression are also mediated via cAMP-PKA since they are inhibited by Rp-cAMP. In isolated perfused rat lungs, PGI2 and PGE2 increases VEGF mRNA abundance whereas Rp-cAMP inhibits the prostaglandin-induced VEGF gene activation. Thus, our data suggest that prostaglandins stimulate VEGF gene expression in monocytic cells and in rat lungs via a cAMP-dependent mechanism.

Vascular Endothelial Growth Factor in Eye Disease

PubMed Central

Penn, J.S.; Madan, A.; Caldwell, R.B.; Bartoli, M.; Caldwell, R.W.; Hartnett, M.E.

2012-01-01

Collectively, angiogenic ocular conditions represent the leading cause of irreversible vision loss in developed countries. In the U.S., for example, retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration are the principal causes of blindness in the infant, working age and elderly populations, respectively. Evidence suggests that vascular endothelial growth factor (VEGF), a 40 kDa dimeric glycoprotein, promotes angiogenesis in each of these conditions, making it a highly significant therapeutic target. However, VEGF is pleiotropic, affecting a broad spectrum of endothelial, neuronal and glial behaviors, and confounding the validity of anti-VEGF strategies, particularly under chronic disease conditions. In fact, among other functions VEGF can influence cell proliferation, cell migration, proteolysis, cell survival and vessel permeability in a wide variety of biological contexts. This article will describe the roles played by VEGF in the pathogenesis of retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration. The potential disadvantages of inhibiting VEGF will be discussed, as will the rationales for targeting other VEGF-related modulators of angiogenesis. PMID:18653375

Vascular endothelial growth factor and amyotrophic lateral sclerosis: the interplay with exercise and noninvasive ventilation.

PubMed

Carilho, Rita; de Carvalho, Mamede; Swash, Michael; Pinto, Susana; Pinto, Anabela; Costa, Júlia

2014-04-01

We evaluated plasma vascular endothelial growth factor (VEGF) levels in patients with amyotrophic lateral sclerosis (ALS) with reference to the effects of respiratory failure, noninvasive ventilation (NIV), and exercise. We studied plasma VEGF levels in 83 ALS patients, 20 healthy controls, and 10 patients with other disorders. There were 4 groups of ALS patients: G1, 27 patients without respiratory problems; G2, 14 patients stabilized on nocturnal NIV; G3, 30 patients presenting with respiratory failure; G4, 12 patients on an aerobic exercise protocol. VEGF plasma levels did not differ significantly between ALS patients and controls, or between ALS groups. In G3, the mean VEGF levels increased 75% during NIV. In G4, the mean VEGF level increased by 300% during the exercise program. VEGF levels did not change during the course of the disease. VEGF levels in ALS depend on changes in ventilation and exercise but are probably not affected by the disease process itself. Copyright © 2013 Wiley Periodicals, Inc.

Placental growth factor neutralising antibodies give limited anti-angiogenic effects in an in vitro organotypic angiogenesis model.

PubMed

Brave, Sandra R; Eberlein, Cath; Shibuya, Masabumi; Wedge, Stephen R; Barry, Simon T

2010-12-01

Vascular Endothelial Growth Factor Receptor (VEGFR) mediated signalling drives angiogenesis. This is predominantly attributed to the activity of VEGFR-2 following binding of VEGF-A. Whether other members of the VEGFR and ligand families such as VEGFR-1 and its ligand Placental Growth Factor (PlGF) can also contribute to developmental and pathological angiogenesis is less clear. We explored the function of PlGF in VEGF-A dependent angiogenesis using an in vitro co-culture assay in which endothelial cells are cultured on a fibroblast feeder layer. In the presence of 2% FS MCDB media (containing limited growth factors) in vitro endothelial tube formation is driven by endogenous angiogenic stimuli which are produced by the fibroblast and endothelial cells. Under these conditions independent sequestration of either free VEGF-A or PlGF with polyclonal and monoclonal antibodies inhibited tube formation suggesting that both ligands are required to drive an angiogenic response. Endothelial tube formation could only be driven within this assay by the addition of exogenous VEGF-A, VEGF-E or VEGF-A/PlGF heterodimer, but not by PlGF alone, implying that activation of either VEGFR-2/VEGFR-1 heterodimers or VEGFR-2 homodimers were responsible for eliciting an angiogenic response directly, but not VEGFR-1 homodimers. In contrast to results obtained with an endogenous angiogenic drive, sequestration of PlGF did not affect endothelial tube formation when the assay was driven by 1 ng/ml exogenous VEGF-A. These data suggest that although neutralising PlGF can be shown to reduce endothelial tube formation in vitro, this effect is only observed under restricted culture conditions and is influenced by VEGF-A. Such data questions whether neutralising PlGF would have a therapeutic benefit in vivo in the presence of pathological concentrations of VEGF-A.

Expression of VEGF₁₆₅b, VEGFR1, VEGFR2 and CD34 in benign and malignant tumors of parotid glands.

PubMed

Błochowiak, Katarzyna J; Sokalski, Jerzy; Bodnar, Magdalena B; Trzybulska, Dorota; Marszałek, Andrzej K; Witmanowski, Henryk

2018-01-01

Vascular endothelial growth factor (VEGF) is an angiogenic factor and could be involved in the pathogenesis of salivary gland tumors. VEGF exerts its biological function by binding to its receptors, VEGFR1 and VEGFR2. An alternative splice variant of VEGF (VEGFxxxb) is an anti-angiogenic factor. Binding VEGF165b with VEGFR2 results in an impaired angiogenic response. The imbalance of VEGFxxx and VEGFxxxb isoforms can underpin pathological angiogenesis. The purpose of this study was to evaluate and compare the expression of VEGF165b, VEGFR1, VEGFR2, and CD34 in benign and malignant parotid gland tumors and to explore the possible correlations between their expression and clinicopathological features of tumors. The study was performed on archived paraffin-embedded tissue samples derived from 70 patients with benign and malignant parotid gland tumors (25 with malignant tumors, 23 with pleomorphic adenoma and 22 with Warthin's tumor). Immunohistochemical staining of selected tissue sections was performed using monoclonal antibodies. Immunohistochemical staining of selected molecules was used for evaluation of their expression in tissue sections. There were no statistically significant differences in the expression of the selected proteins localized in the tumor and surgical margin taken from the same patient. Expression of VEGFR2 correlated with VEGF165b in mixed tumors. There was a statistically significant difference in the expression of VEGFR1 in malignant tumors between females and males, and between the expression of VEGFR1 and the score of T classification in malignant tumors. VEGF165b cannot be treated as a prognostic factor. VEGF receptors correlated with selected clinicopathological data of malignant tumors, indicating their possible role as a prognostic marker. The balance of VEGF isoforms have a limited influence on the development of parotid glands tumors. The correlation between VEGF165b and VEGFR2 in mixed tumors suggests the existence of an additional antiangiogenic pathway in poorly vascularized mixed tumors.

Involvement of Vascular Endothelial Growth Factor in Kaposi's Sarcoma Associated with Acquired Immunodeficiency Syndrome

PubMed Central

Sakurada, Shinsaku; Kato, Tetsuji; Mashiba, Kohichi; Mori, Shigeo

1996-01-01

To examine the role of vascular endothelial growth factor (VEGF) in the development of edema associated with Kaposi's sarcoma (KS) in acquired immunodeficiency syndrome (AIDS), we exploited animal model systems to detect the activity that induces vascular hyper‐permeability (VHP) using cultured AIDS‐KS spindle cells. Cultured AIDS‐KS spindle cells and conditioned medium (AIDS‐KS‐CM) that had been semi‐purified through a heparin affinity column were tested for the ability to induce VHP in animals. The AIDS‐KS spindle cells and AIDS‐KS‐CM induced VHP that was histamine‐independent. The VHP‐inducing activity was detected in the 0.5 M NaCl fraction from the heparin affinity column and was blocked by anti‐VEGF neutralizing antibody. In addition, the production of VEGF was demonstrated in fresh AIDS‐KS tissue as well as in cultured AIDS‐KS cells, while control cells were negative for VEGF production. From these observations, we concluded that AIDS‐KS cells produce a factor(s) that promotes VHP, and this factor could be VEGF. PMID:9045943

Association of Vascular Endothelial Growth Factor Expression with Tumor Angiogenesis and with Early Relapse in Primary Breast Cancer

PubMed Central

Hoshina, Seigo; Takayanagi, Toshiaki; Tominaga, Takeshi

1994-01-01

Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti‐VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF‐rich tumors was clearly higher than that in VEGF‐poor tumors (P<0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse‐free survival rate of VEGF‐rich tumors was significantly worse than that of VEGF‐poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer. PMID:7525523

Quantitation of Vascular Endothelial Growth Factor and Interleukin-6 in Different Stages of Breast Cancer.

PubMed

Raghunathachar Sahana, Kabbathi; Akila, Prashant; Prashant, Vishwanath; Sharath Chandra, Bellekere; Nataraj Suma, Maduvanahalli

2017-10-01

Determination of the impact of angiogenesis on tumor development and progression is essential. This study aimed to determine the serum levels of Vascular endothelial growth factor (VEGF) and Interleukin 6 (IL-6) in breast carcinoma, and to correlate them with tumor size, lymph node involvement, and cancer stage. Under aseptic precautions 5 ml of venous blood was collected from 37 breast cancer patients and 20 healthy females after obtaining due consent and ethical committee clearance. Serum levels of VEGF and IL-6 were determined by enzyme-linked immunosorbent assay (ELISA). Serum IL-6 and VEGF levels were both significantly greater in patients than controls (P = 0.001, P = 0.001, respectively). The serum IL-6 and VEGF levels also significantly correlated with TNM staging (P = 0.001, P = 0.001). Serum IL-6 and VEGF positively correlated with each other (r 2 = 0.668, P = 0.01). Serum IL-6 and VEGF levels did not correlate with tumor size (P = 0.45, P = 0.17) or lymph node metastasis (P = 0.95, P = 0.68). Serum IL-6 and VEGF were greater in breast cancer patients than controls. The levels increased with advanced tumor, nodes, metastasis (TNM) staging, thus correlating with the patients' prognoses. Serum IL-6 and VEGF levels can be used as diagnostic tools and prognostic factors in breast cancer.

Serum levels, and bone marrow immunohistochemical expression of, vascular endothelial growth factor in patients with chronic myeloproliferative diseases.

PubMed

Panteli, Katerina; Bai, Maria; Hatzimichael, Eleftheria; Zagorianakou, Nektaria; Agnantis, Niki John; Bourantas, Konstantinos

2007-12-01

Current data suggest that angiogenesis plays a significant role in the pathogenesis and progression of chronic myeloproliferative diseases (cMPDs). In the present study, we evaluated serum levels of vascular endothelial growth factor (VEGF) in 83 patients with cMPDs [myelofibrosis with myeloid metaplasia (MMM, n = 25), essential thrombocythaemia (ET, n = 40), polycythaemia vera (PV, n = 8) and chronic myeloid leukemia (CML, n = 10)] and in 27 healthy individuals. Serum VEGF levels were significantly increased in patients with cMPDs compared to healthy individuals (all p values were < or = 0.05) and were significantly correlated with bone marrow microvessel density (MVD) (p = 0.0013). In addition, the immunohistochemical expression of VEGF protein in bone marrow biopsy specimens were analyzed in 61 patients with cMPDs, (ET, n = 36 and MMM, n = 25) and in 27 healthy individuals. The cellular distribution of VEGF expression was similar in bone marrow specimens of patients and healthy individuals. VEGF protein was detected mainly in erythroid cells, whereas myeloid cells and megakaryocytes exhibited a variable expression of the protein. The percentage of bone marrow VEGF positive cells was positively correlated with serum levels of VEGF (p = 0.001). The results of the present study suggest that, VEGF is a major angiogenetic factor in patients with cMPDs and contributes to the pathogenesis of these diseases.

Role of VEGF-C and VEGF-D in lymphangiogenesis in gastric cancer.

PubMed

Yonemura, Yutaka; Endo, Yoshio; Tabata, Kayoko; Kawamura, Taiichi; Yun, Hyo-Yung; Bandou, Etsurou; Sasaki, Takuma; Miura, Masahiro

2005-10-01

The molecular mechanisms of lymphangiogenesis induced by vascular endothelial growth factor (VEGF)-C and VEGF-D in gastric cancer were studied. VEGF-C and VEGF-D gene expression vectors were transfected into the gastric cancer cell line KKLS, which did not originally express VEGF-C and VEGF-D, and stable transfectants (KKLS/VEGF-C and KKLS/VEGF-D) were established. The cell lines were inoculated into the subserosal layer of the stomach and subcutaneous tissue of nude mice. VEGF-C and VEGF-D expression in KKLS/VEGF-C and KKLS/VEGF-D cells was found by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. Expression of mouse VEGF receptor (VEGFR)-2 and mouse VEGFR-3 mRNA was detected in the KKLS/VEGF-C and KKLS/VEGF-D gastric tumors. Newly formed lymphatic vessels were detected not only in the periphery but also in the center of the tumors. The intratumor lymphatic vessels connected with the preexisting lymphatic vessels in the muscularis mucosa. The average numbers of lymphatic vessels in KKLS/VEGF-C (52.0 +/- 9.5) and KKLS/VEGF-D (16.4 +/- 0.6) gastric tumors were significantly higher than that in the KKLS/control vector tumors (4.0 +/- 1.4). VEGF-C and VEGF-D may induce neoformation of lymphatic vessels in experimental gastric tumors by the induction of VEGFR-3 expression.

Placental growth factor expression is reversed by antivascular endothelial growth factor therapy under hypoxic conditions.

PubMed

Zhou, Ai-Yi; Bai, Yu-Jing; Zhao, Min; Yu, Wen-Zhen; Huang, Lv-Zhen; Li, Xiao-Xin

2014-08-01

Clinical trials have revealed that the antivascular endothelial growth factor (VEGF) therapies are effective in retinopathy of prematurity (ROP). But the low level of VEGF was necessary as a survival signal in healthy conditions, and endogenous placental growth factor (PIGF) is redundant for development. The purpose of this study was to elucidate the PIGF expression under hypoxia as well as the influence of anti-VEGF therapy on PIGF. CoCl2-induced hypoxic human umbilical vein endothelial cells (HUVECs) were used for an in vitro study, and oxygen-induced retinopathy (OIR) mice models were used for an in vivo study. The expression patterns of PIGF under hypoxic conditions and the influence of anti-VEGF therapy on PIGF were evaluated by quantitative reverse transcription-polymerase chain reaction (RTPCR). The retinal avascular areas and neovascularization (NV) areas of anti-VEGF, anti-PIGF and combination treatments were calculated. Retina PIGF concentration was evaluated by ELISA after treatment. The vasoactive effects of exogenous PIGF on HUVECs were investigated by proliferation and migration studies. PIGF mRNA expression was reduced by hypoxia in OIR mice, in HUVECs under hypoxia and anti-VEGF treatment. However, PIGF expression was reversed by anti-VEGF therapy in the OIR model and in HUVECs under hypoxia. Exogenous PIGF significantly inhibited HUVECs proliferation and migration under normal conditions, but it stimulated cell proliferation and migration under hypoxia. Anti-PIGF treatment was effective for neovascular tufts in OIR mice (P<0.05). The finding that PIGF expression is iatrogenically up-regulated by anti-VEGF therapy provides a consideration to combine it with anti-PIGF therapy.

Chronic ethanol consumption modulates growth factor release, mucosal cytokine production, and microRNA expression in nonhuman primates.

PubMed

Asquith, Mark; Pasala, Sumana; Engelmann, Flora; Haberthur, Kristen; Meyer, Christine; Park, Byung; Grant, Kathleen A; Messaoudi, Ilhem

2014-04-01

Chronic alcohol consumption has been associated with enhanced susceptibility to both systemic and mucosal infections. However, the exact mechanisms underlying this enhanced susceptibility remain incompletely understood. Using a nonhuman primate model of ethanol (EtOH) self-administration, we examined the impact of chronic alcohol exposure on immune homeostasis, cytokine, and growth factor production in peripheral blood, lung, and intestinal mucosa following 12 months of chronic EtOH exposure. EtOH exposure inhibited activation-induced production of growth factors hepatocyte growth factor (HGF), granulocyte colony-stimulating factor (G-CSF), and vascular-endothelial growth factor (VEGF) by peripheral blood mononuclear cells (PBMC). Moreover, EtOH significantly reduced the frequency of colonic Th1 and Th17 cells in a dose-dependent manner. In contrast, we did not observe differences in lymphocyte frequency or soluble factor production in the lung of EtOH-consuming animals. To uncover mechanisms underlying reduced growth factor and Th1/Th17 cytokine production, we compared expression levels of microRNAs in PBMC and intestinal mucosa. Our analysis revealed EtOH-dependent up-regulation of distinct microRNAs in affected tissues (miR-181a and miR-221 in PBMC; miR-155 in colon). Moreover, we were able to detect reduced expression of the transcription factors STAT3 and ARNT, which regulate expression of VEGF, G-CSF, and HGF and contain targets for these microRNAs. To confirm and extend these observations, PBMC were transfected with either mimics or antagomirs of miR-181 and miR-221, and protein levels of the transcription factors and growth factors were determined. Transfection of microRNA mimics led to a reduction in both STAT3/ARNT as well as VEGF/HGF/G-CSF levels. The opposite outcome was observed when microRNA antagomirs were transfected. Chronic EtOH consumption significantly disrupts both peripheral and mucosal immune homeostasis, and this dysregulation may be mediated by changes in microRNA expression. Copyright © 2013 by the Research Society on Alcoholism.

VEGF induces sensory and motor peripheral plasticity, alters bladder function, and promotes visceral sensitivity

PubMed Central

2012-01-01

Background This work tests the hypothesis that bladder instillation with vascular endothelial growth factor (VEGF) modulates sensory and motor nerve plasticity, and, consequently, bladder function and visceral sensitivity. In addition to C57BL/6J, ChAT-cre mice were used for visualization of bladder cholinergic nerves. The direct effect of VEGF on the density of sensory nerves expressing the transient receptor potential vanilloid subfamily 1 (TRPV1) and cholinergic nerves (ChAT) was studied one week after one or two intravesical instillations of the growth factor. To study the effects of VEGF on bladder function, mice were intravesically instilled with VEGF and urodynamic evaluation was assessed. VEGF-induced alteration in bladder dorsal root ganglion (DRG) neurons was performed on retrogradly labeled urinary bladder afferents by patch-clamp recording of voltage gated Na+ currents. Determination of VEGF-induced changes in sensitivity to abdominal mechanostimulation was performed by application of von Frey filaments. Results In addition to an overwhelming increase in TRPV1 immunoreactivity, VEGF instillation resulted in an increase in ChAT-directed expression of a fluorescent protein in several layers of the urinary bladder. Intravesical VEGF caused a profound change in the function of the urinary bladder: acute VEGF (1 week post VEGF treatment) reduced micturition pressure and longer treatment (2 weeks post-VEGF instillation) caused a substantial reduction in inter-micturition interval. In addition, intravesical VEGF resulted in an up-regulation of voltage gated Na+ channels (VGSC) in bladder DRG neurons and enhanced abdominal sensitivity to mechanical stimulation. Conclusions For the first time, evidence is presented indicating that VEGF instillation into the mouse bladder promotes a significant increase in peripheral nerve density together with alterations in bladder function and visceral sensitivity. The VEGF pathway is being proposed as a key modulator of neural plasticity in the pelvis and enhanced VEGF content may be associated with visceral hyperalgesia, abdominal discomfort, and/or pelvic pain. PMID:23249422

Early Growth Response-1 Induces and Enhances Vascular Endothelial Growth Factor-A Expression in Lung Cancer Cells

PubMed Central

Shimoyamada, Hiroaki; Yazawa, Takuya; Sato, Hanako; Okudela, Koji; Ishii, Jun; Sakaeda, Masashi; Kashiwagi, Korehito; Suzuki, Takehisa; Mitsui, Hideaki; Woo, Tetsukan; Tajiri, Michihiko; Ohmori, Takahiro; Ogura, Takashi; Masuda, Munetaka; Oshiro, Hisashi; Kitamura, Hitoshi

2010-01-01

Vascular endothelial growth factor-A (VEGF-A) is crucial for angiogenesis, vascular permeability, and metastasis during tumor development. We demonstrate here that early growth response-1 (EGR-1), which is induced by the extracellular signal–regulated kinase (ERK) pathway activation, activates VEGF-A in lung cancer cells. Increased EGR-1 expression was found in adenocarcinoma cells carrying mutant K-RAS or EGFR genes. Hypoxic culture, siRNA experiment, luciferase assays, chromatin immunoprecipitation, electrophoretic mobility shift assays, and quantitative RT-PCR using EGR-1–inducible lung cancer cells demonstrated that EGR-1 binds to the proximal region of the VEGF-A promoter, activates VEGF-A expression, and enhances hypoxia inducible factor 1α (HIF-1α)-mediated VEGF-A expression. The EGR-1 modulator, NAB-2, was rapidly induced by increased levels of EGR-1. Pathology samples of human lung adenocarcinomas revealed correlations between EGR-1/HIF-1α and VEGF-A expressions and relative elevation of EGR-1 and VEGF-A expression in mutant K-RAS- or EGFR-carrying adenocarcinomas. Both EGR-1 and VEGF-A expression increased as tumors dedifferentiated, whereas HIF-1α expression did not. Although weak correlation was found between EGR-1 and NAB-2 expressions on the whole, NAB-2 expression decreased as tumors dedifferentiated, and inhibition of DNA methyltransferase/histone deacetylase increased NAB-2 expression in lung cancer cells despite no epigenetic alteration in the NAB-2 promoter. These findings suggest that EGR-1 plays important roles on VEGF-A expression in lung cancer cells, and epigenetic silencing of transactivator(s) associated with NAB-2 expression might also contribute to upregulate VEGF-A expression. PMID:20489156

Human telomerase reverse transcriptase regulates vascular endothelial growth factor expression via human papillomavirus oncogene E7 in HPV-18-positive cervical cancer cells.

PubMed

Li, Fang; Cui, Jinquan

2015-07-01

Human papillomavirus (HPV) infection induces chronic and precancerous lesions and results in invasive cervical cancer. Human telomerase as well as inflammatory and angiogenic factors such as telomerase reverse transcriptase (hTERT) or vascular endothelial growth factor (VEGF) could play a role in regulating HPV-induced cervical cancer. This study investigated underlying molecular events in HPV-induced HPV-positive cervical cancer through hTERT and VEGF in vitro. Expressions of hTERT, a rate-limiting subunit of telomerase, and VEGF mRNA and proteins were, respectively, assessed by qRT-PCR, ELISA, and TRAP-ELISA in HPV-positive tissue samples and cervical cancer cell lines. To assess hTERT and VEGF secretion, hTERT overexpression and knockdown were conducted in HPV-18-positive Hela cells by hTERT cDNA and shRNA transfection, respectively. Then, the effect of HPV E6 and E7 on VEGF expressions was assessed in HPV-negative cervical cancer cells. Data have shown that VEGF expression levels are associated with hTERT expressions and telomerase activity in HPV-positive cervical cancer tissues and cells. Knockdown of hTERT expression down-regulated VEGF expressions, whereas overexpression of hTERT up-regulated VEGF expressions in HPV-18-positive Hela cells. Furthermore, HPV E7 oncoprotein was necessary for hTERT to up-regulate VEGF expressions in HPV-negative cervical cancer cells. Data from this current study indicate that HPV oncoproteins up-regulated hTERT and telomerase activity and in turn promoted VEGF expressions, which could be a key mechanism for HPV-induced cervical cancer development and progression.

Expression and localization of endocrine gland-derived vascular endothelial growth factor (EG-VEGF) in human pancreas and pancreatic adenocarcinoma.

PubMed

Morales, Angélica; Vilchis, Felipe; Chávez, Bertha; Chan, Carlos; Robles-Díaz, Guillermo; Díaz-Sánchez, Vicente

2007-10-01

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) was recently identified as the first tissue-specific angiogenic molecule. EG-VEGF (the gene product of PROK-1) appears to be expressed exclusively in steroid-producing organs such as the ovary, testis, adrenals and placenta. Since the human pancreatic cells retain steroidogenic activity, in the present study we ascertained whether this angiogenic factor is expressed in normal pancreas and pancreatic adenocarcinoma. Tissue samples from normal males (n=5), normal females (n=5) and from surgically resected adenocarcinomas (n=2) were processed for RT-PCR and immunohistochemical studies. Results from semi-quantitative analysis by RT-PCR suggest a distinct expression level for EG-VEGF in the different tissue samples. The relative amount of EG-VEGF mRNA in pancreas was more abundant in female adenocarcinoma (0.89) followed by male adenocarcinoma (0.71), than normal female (0.64) and normal male (0.38). The expression of mRNA for EG-VEGF in normal tissue was significantly higher in females than in males. All samples examined showed specific immunostaining for EG-VEGF. In male preparations, the positive labeling was localized predominantly within the pancreatic islets while in female preparations the main staining was detected towards the exocrine portion. Specific immunolabeling was also observed in endothelial cells of pancreatic blood vessels. Our data provide evidence that the human pancreas expresses the EG-VEGF, a highly specific mitogen which regulates proliferation and differentiation of the vascular endothelium. The significance of this finding could be interpreted as either, EG-VEGF is not exclusive of endocrine organs, or the pancreas should be considered as a functional steroidogenic tissue. The extent of the expression of EG-VEGF appears to have a dimorphic pattern in normal and tumoral pancreatic tissue.

Effects of aspirin on intra-platelet vascular endothelial growth factor, angiopoietin-1, and p-selectin levels in hypertensive patients.

PubMed

Nadar, Sunil; Blann, Andrew D; Lip, Gregory Y H

2006-09-01

Although aspirin is useful in reducing platelet activation and cardiovascular events, its effects on platelet levels of angiogenic factors, such as vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1), and markers of platelet activation in hypertension are unknown. The aim of this study was to study the effects of aspirin on the platelet morphology, plasma and platelet levels of VEGF (sVEGF and pVEGF respectively), Ang-1 (sAng-1 and pAng-1 respectively), and P-selectin (sPsel and pPsel respectively) in patients with well controlled hypertension. A total of 35 aspirin-naive, hypertensive patients (29 male and six female; mean age 64 years) were compared with 30 (23 male, seven female, mean age 59 years) normotensive control subjects. Blood was collected for plasma VEGF, P-selectin, and Ang-1 (enzyme-linked immunoassay), intra-platelet levels of VEGF, Ang-1, and P-selectin, and platelet volume and mass. Research indices in hypertensive patients were studied before and after 3 months treatment with aspirin 75 mg daily. Hypertensive patients had significantly higher plasma levels of VEGF (P=.04), Ang-1 (P<.001), as well as pVEGF (P=.008), pAng-1(P=.001), sPsel (P=.02), pPsel (P<.001), and mean platelet mass (P=.01) when compared with control subjects. After treatment with aspirin for 3 months, there were significant reductions in plasma VEGF (P=.01), pAng-1 (P=.04), sPsel (P=.001), and pPsel (P<.001) levels, but not levels of platelet VEGF and plasma Ang-1. Neither pVEGF nor pAng-1 correlated with blood pressure or with their respective plasma levels. The use of aspirin in high-risk hypertensive patients leads to a reduction in intra-platelet angiogenic growth factors and platelet activation. This may have implications for the use of aspirin in conditions (such as vascular disease) that have been associated with an increase in angiogenesis and platelet activation.

Autoantibodies in dilated cardiomyopathy induce vascular endothelial growth factor expression in cardiomyocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saygili, Erol, E-mail: erol.saygili@med.uni-duesseldorf.de; Noor-Ebad, Fawad; Schröder, Jörg W.

2015-09-11

Background: Autoantibodies have been identified as major predisposing factors for dilated cardiomyopathy (DCM). Patients with DCM show elevated serum levels of vascular endothelial growth factor (VEGF) whose source is unknown. Besides its well-investigated effects on angiogenesis, evidence is present that VEGF signaling is additionally involved in fibroblast proliferation and cardiomyocyte hypertrophy, hence in cardiac remodeling. Whether autoimmune effects in DCM impact cardiac VEGF signaling needs to be elucidated. Methods: Five DCM patients were treated by the immunoadsorption (IA) therapy on five consecutive days. The eluents from the IA columns were collected and prepared for cell culture. Cardiomyocytes from neonatal ratsmore » (NRCM) were incubated with increasing DCM-immunoglobulin-G (IgG) concentrations for 48 h. Polyclonal IgG (Venimmun N), which was used to restore IgG plasma levels in DCM patients after the IA therapy was additionally used for control cell culture purposes. Results: Elevated serum levels of VEGF decreased significantly after IA (Serum VEGF (ng/ml); DCM pre-IA: 45 ± 9.1 vs. DCM post–IA: 29 ± 6.7; P < 0.05). In cell culture, pretreatment of NRCM by DCM-IgG induced VEGF expression in a time and dose dependent manner. Biologically active VEGF that was secreted by NRCM significantly increased BNP mRNA levels in control cardiomyocytes and induced cell-proliferation of cultured cardiac fibroblast (Fibroblast proliferation; NRCM medium/HC-IgG: 1 ± 0.0 vs. NRCM medium/DCM-IgG 100 ng/ml: 5.6 ± 0.9; P < 0.05). Conclusion: The present study extends the knowledge about the possible link between autoimmune signaling in DCM and VEGF induction. Whether this observation plays a considerable role in cardiac remodeling during DCM development needs to be further elucidated. - Highlights: • Mechanisms of remodeling in dilated cardiomyopathy (DCM) are not fully understood. • Autoantibodies have been identified as major predisposing factors for DCM. • DCM patients show high serum levels of VEGF. • Recent data indicate that VEGF is involved in cardiac remodeling processes. • Whether autoimmune processes in DCM are involved in VEGF signaling are unclear.« less

Localization of vascular endothelial growth factor in the zona pellucida of developing ovarian follicles in the rat: a possible role in destiny of follicles.

PubMed

Celik-Ozenci, Ciler; Akkoyunlu, Gokhan; Kayisli, Umit Ali; Arici, Aydin; Demir, Ramazan

2003-11-01

There is increasing evidence that in many species angiogenic factors, such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), may have important roles in folliculogenesis. The aim of this study is to determine the localization of VEGF and its receptors, Flt-1 and KDR, and bFGF expression in the rat ovary and to evaluate their distributions throughout the different follicular stages. Out of 20 virginal female rats, 10 were studied during the natural ovarian cycle without any ovulation induction. The other 10 were superovulated and their ovaries were studied by western analysis and immunohistochemistry. Granulosa cells (GC) and oocytes of primordial follicles were negative for VEGF. In early primary follicles, VEGF was present in the oocyte but its immunoreactivity was weak, while newly developing zona pellucida (ZP) of primary follicles was negative for VEGF. Subsequently, with the commencement of antral spaces between GC of the secondary follicle, ZP of some secondary follicles became strongly positive for VEGF, forming a continuous ring around the oocyte. In preovulatory mature follicles granulosa and theca interna (TI) cells showed a weak immunoreactivity for VEGF. Western blot analyses have also demonstrated that VEGF, a 26-kDa protein, was present in follicles. Moreover, in ovulated cumulus-oocyte complex we observed a halo-like immunoreactivity of VEGF around the fully mature oocyte. The immunoreactivity for Flt-1 and KDR receptors in growing follicles was mostly limited to GC and TI cells. Anti-bFGF did not exhibit any immunoreactivity in ZP of follicles at any stage. Its expression was weak in GC of the follicles at different stages, whereas, it could be localized to some extent in the blood capillaries of TI of antral follicles and in blood vessels localized in the stroma. Interestingly, VEGF immunoreactivity in the ZP of some secondary follicles is very striking. Accordingly, the possibility that VEGF may be an important regulatory molecule for the dominant follicle selection or atresia should be considered.

VEGF improves survival of mesenchymal stem cells in infarcted hearts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pons, Jennifer; Huang Yu; Arakawa-Hoyt, Janice

2008-11-14

Bone marrow-derived mesenchymal stem cells (MSC) are a promising source for cell-based treatment of myocardial infarction (MI), but existing strategies are restricted by low cell survival and engraftment. We examined whether vascular endothelial growth factor (VEGF) improve MSC viability in infracted hearts. We found long-term culture increased MSC-cellular stress: expressing more cell cycle inhibitors, p16{sup INK}, p21 and p19{sup ARF}. VEGF treatment reduced cellular stress, increased pro-survival factors, phosphorylated-Akt and Bcl-xL expression and cell proliferation. Co-injection of MSCs with VEGF to MI hearts increased cell engraftment and resulted in better improvement of cardiac function than that injected with MSCs ormore » VEGF alone. In conclusion, VEGF protects MSCs from culture-induce cellular stress and improves their viability in ischemic myocardium, which results in improvements of their therapeutic effect for the treatment of MI.« less

Vascular endothelial growth factor inhibitor-induced hypertension: from pathophysiology to prevention and treatment based on long-acting nitric oxide donors.

PubMed

Kruzliak, Peter; Novák, Jan; Novák, Miroslav

2014-01-01

Hypertension is the most common adverse effect of the inhibitors of vascular endothelial growth factor (VEGF) pathway-based therapy (VEGF pathway inhibitors therapy, VPI therapy) in cancer patients. VPI includes monoclonal antibodies against VEGF, tyrosine kinase inhibitors, VEGF Traps, and so-called aptamers that may become clinically relevant in the future. All of these substances inhibit the VEGF pathway, which in turn causes a decrease in nitric oxide (NO) and an increase in blood pressure, with the consequent development of hypertension and its final events (e.g., myocardial infarction or stroke). To our knowledge, there is no current study on how to provide an optimal therapy for patients on VPI therapy with hypertension. This review summarizes the roles of VEGF and NO in vessel biology, provides an overview of VPI agents, and suggests a potential treatment procedure for patients with VPI-induced hypertension.

In vitro and in vivo evaluation of calcium phosphate composite scaffolds containing BMP-VEGF loaded PLGA microspheres for the treatment of avascular necrosis of the femoral head.

PubMed

Zhang, Hao-Xuan; Zhang, Xiu-Ping; Xiao, Gui-Yong; Hou, Yong; Cheng, Lei; Si, Meng; Wang, Shuai-Shuai; Li, Yu-Hua; Nie, Lin

2016-03-01

Avascular necrosis of the femoral head (ANFH) is difficult to treat due to high pressure and hypoxia, and reduced levels of growth factors such as bone morphogenetic protein (BMP), and vascular endothelial growth factor (VEGF). We generated a novel calcium phosphate (CPC) composite scaffold, which contains BMP-VEGF-loaded poly-lactic-co-glycolic acid (PLGA) microspheres (BMP-VEGF-PLGA-CPC). The BMP-VEGF-loaded microspheres have an encapsulation efficiency of 89.15% for BMP, and 78.55% for VEGF. The BMP-VEGF-PLGA-CPC scaffold also demonstrated a porosity of 62% with interconnected porous structures, and pore sizes of 219 μm and compressive strength of 6.60 MPa. Additionally, bone marrow mesenchymal stem cells (BMSCs) were seeded on scaffolds in vitro. Further characterization showed that the BMP-VEGF-PLGA-CPC scaffolds were biocompatible and enhanced osteogenesis and angiogenesis in vitro. Using a rabbit model of ANFH, BMP-VEGF-PLGA-CPC scaffolds were implanted into the bone tunnels of core decompression in the femoral head for 6 and 12 weeks. Radiographic and histological analysis demonstrated that the BMP-VEGF-PLGA-CPC scaffolds exhibited good biocompatibility, and osteogenic and angiogenic activity in vivo. These results indicate that the BMP-VEGF-PLGA-CPC scaffold may improve the therapeutic effect of core decompression surgery and be used as a treatment for ANFH. Copyright © 2015 Elsevier B.V. All rights reserved.

Systemic Hypoxia Changes the Organ-Specific Distribution of Vascular Endothelial Growth Factor and Its Receptors

NASA Astrophysics Data System (ADS)

Marti, Hugo H.; Risau, Werner

1998-12-01

Vascular endothelial growth factor (VEGF) plays a key role in physiological blood vessel formation and pathological angiogenesis such as tumor growth and ischemic diseases. Hypoxia is a potent inducer of VEGF in vitro. Here we demonstrate that VEGF is induced in vivo by exposing mice to systemic hypoxia. VEGF induction was highest in brain, but also occurred in kidney, testis, lung, heart, and liver. In situ hybridization analysis revealed that a distinct subset of cells within a given organ, such as glial cells and neurons in brain, tubular cells in kidney, and Sertoli cells in testis, responded to the hypoxic stimulus with an increase in VEGF expression. Surprisingly, however, other cells at sites of constitutive VEGF expression in normal adult tissues, such as epithelial cells in the choroid plexus and kidney glomeruli, decreased VEGF expression in response to the hypoxic stimulus. Furthermore, in addition to VEGF itself, expression of VEGF receptor-1 (VEGFR-1), but not VEGFR-2, was induced by hypoxia in endothelial cells of lung, heart, brain, kidney, and liver. VEGF itself was never found to be up-regulated in endothelial cells under hypoxic conditions, consistent with its paracrine action during normoxia. Our results show that the response to hypoxia in vivo is differentially regulated at the level of specific cell types or layers in certain organs. In these tissues, up- or down-regulation of VEGF and VEGFR-1 during hypoxia may influence their oxygenation after angiogenesis or modulate vascular permeability.

Interleukin-6 triggers human cerebral endothelial cells proliferation and migration: The role for KDR and MMP-9

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yao, Jianhua S.; Zhai Wenwu; Young, William L.

2006-04-21

Interleukin-6 (IL-6) is involved in angiogenesis. However, the underlying mechanisms are unknown. Using human cerebral endothelial cell (HCEC), we report for First time that IL-6 triggers HCEC proliferation and migration in a dose-dependent manner, specifically associated with enhancement of VEGF expression, up-regulated and phosphorylated VEGF receptor-2 (KDR), and stimulated MMP-9 secretion. We investigated the signal pathway of IL-6/IL-6R responsible for KDR's regulation. Pharmacological inhibitor of PI3K failed to inhibit IL-6-mediated VEGF overexpression, while blocking ERK1/2 with PD98059 could abolish IL-6-induced KDR overexpression. Further, neutralizing endogenous VEGF attenuated KDR expression and phosphorylation, suggesting that IL-6-induced KDR activation is independent of VEGFmore » stimulation. MMP-9 inhibitor GM6001 significantly decreases HCEC proliferation and migration (p < 0.05), indicating the crucial function of MMP-9 in promoting angiogenic changes in HCECs. We conclude that IL-6 triggers VEGF-induced angiogenic activity through increasing VEGF release, up-regulates KDR expression and phosphorylation through activating ERK1/2 signaling, and stimulates MMP-9 overexpression.« less

Systemic administration of vascular endothelial growth factor monoclonal antibody reduces the growth of papillary thyroid carcinoma in a nude mouse model.

PubMed

Bauer, Andrew J; Patel, Aneeta; Terrell, Richard; Doniparthi, Krishna; Saji, Motoyasu; Ringel, Matthew; Tuttle, R Michael; Francis, Gary L

2003-01-01

Papillary thyroid carcinomas (PTC) are the most common thyroid cancers in children. Most are successfully treated with surgery and radioactive iodine, but some persist. PTC express high levels of vascular endothelial growth factor (VEGF) and VEGF receptor (Flt-1). PTC with the most intense expression of VEGF have the greatest recurrence risk. We hypothesized that blockade of VEGF would inhibit PTC growth. To test this, we used systemic VEGF monoclonal antibody (VEGF-MAb) to treat PTC xenografts in nude mice. Treated animals (n = 9) received 200 microg VEGF-MAb by daily i.p. injection for 10 wk, while control animals (n = 9) received vehicle alone. Tumor size was significantly reduced in the treatment group (0.28 +/- 0.06 vs 1.05 +/- 0.25 g, p = 0.008). VEGF immunostaining was more intense (2.57 +/- 0.30 vs 1.75 +/- 0.25, p = 0.06) and the number of p53 positive cells was increased (1.66 +/- 0.24 vs 0.83 +/- 0.31, p = 0.048) in treated tumors. Animal weight was similar in both groups (29.1 +/- 1.1 vs 27.4 +/- 1.1 g, p = 0.30). In conclusion, systemic VEGF-MAb significantly reduced the growth of PTC, suggesting that VEGF-MAb might be useful for treatment of resistant PTC.

Myocardial expression of the vascular endothelial growth factor (VEGF) after endocardial laser revascularization (ELR)

NASA Astrophysics Data System (ADS)

Rommerscheid, Jan; Theisen, Dirk; Schmuecker, G.; Brinkmann, Ralf; Broll, R.

2001-10-01

Background. Endocardial laser revascularization (ELR) is a new technique to treat patients with severe coronary artery disease (CAD) in a percutaneous approach. The results show a significant improvement of symptoms, but the mechanism of action is still unknown. One main theory is the angiogenesis for which Vascular Endothelial Growth Factor (VEGF) is the keypromotor. We investigated immunohistochemically the VEGF-expression after ELR in porcine hearts over a timeperiod of four weeks. Methods. ELR was performed with a single-pulse Thulium:YAG laser. 15 pigs were treated with ELR and the hearts were harvested at five timeperiods: directly (group I), 3 days (group II), 1 week (group III), 2 weeks (group IV) and 4 weeks (group V) after ELR. Each group consisted of three pigs. Immunohistochemically the VEGF-expression was assessed by staining with a polyclonal antibody against VEGF and cellcounting using an expression index (VEGF-EI) Results. A maximum of VEGF-expression was found three days (group II) after ELR with a VEGF-EI of 97%. At 1 week (group III) the VEGF-EI was similar high with 93%. Along the timecourse the index decreased to 22% at 4 weeks (groupV). Conclusions. Our findings show that ELR leads to an local upregulation of VEGF around the channels. The resulting angiogenesis could be the mechanism for the relief of angina.

Extracorporeal shock wave therapy combined with vascular endothelial growth factor-C hydrogel for lymphangiogenesis.

PubMed

Kim, In Gul; Lee, Ji Youl; Lee, David S; Kwon, Jeong Yi; Hwang, Ji Hye

2013-01-01

Lymphedema is a clinically incurable disease that occurs commonly after lymph node dissection and/or irradiation. Several studies have recently demonstrated that extracorporeal shock wave therapy (ESWT) could promote lymphangiogenesis associated with expression of vascular endothelial growth factor (VEGF)-C. This research concerned primarily the synergistic effect of ESWT combined with VEGF-C incorporated hydrogel (VEGF-C hydrogel) combination therapy for promoting lymphangiogenesis and ultimately alleviating lymphedema. The VEGF-C hydrogel was applied to the injury site in a mouse model of lymphedema and then regularly underwent ESWT (0.05 mJ/mm(2), 500 shots) every 3 days for 4 weeks. Four weeks after the treatment, mice treated with VEGF-C hydrogel and ESWT showed signs of the greatest decrease in edema/collagenous deposits when compared with the other experimental group. LYVE-1-positive vessels also revealed that the VEGF-C/ESWT group had significantly induced the growth of new lymphatic vessels compared to the other groups. Western blot analysis showed that expression of VEGF-C (1.24-fold) and VEGF receptor-3 (1.41-fold) was significantly increased in the VEGF-C/ESWT group compared to the normal group. These results suggested that VEGF-C and ESWT had a synergistic effect and were very effective in alleviating the symptoms of lymphedema and promoting lymphangiogenesis. Copyright © 2012 S. Karger AG, Basel.

Chemical allergens stimulate human epidermal keratinocytes to produce lymphangiogenic vascular endothelial growth factor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bae, Ok-Nam; Ahn, Seyeon; Jin, Sun Hee

2015-03-01

Allergic contact dermatitis (ACD) is a cell-mediated immune response that involves skin sensitization in response to contact with various allergens. Angiogenesis and lymphangiogenesis both play roles in the allergic sensitization process. Epidermal keratinocytes can produce vascular endothelial growth factor (VEGF) in response to UV irradiation and during wound healing. However, the effect of haptenic chemical allergens on the VEGF production of human keratinocytes, which is the primary contact site of toxic allergens, has not been thoroughly researched. We systematically investigated whether immune-regulatory cytokines and chemical allergens would lead to the production of VEGF in normal human keratinocytes (NHKs) in culture.more » VEGF production significantly increased when NHKs were treated with IFNγ, IL-1α, IL-4, IL-6, IL-17A, IL-22 or TNFα. Among the human sensitizers listed in the OECD Test Guideline (TG) 429, we found that CMI/MI, DNCB, 4-phenylenediamine, cobalt chloride, 2-mercaptobenzothiazole, citral, HCA, cinnamic alcohol, imidazolidinyl urea and nickel chloride all significantly upregulated VEGF production in NHKs. In addition, common human haptenic allergens such as avobenzone, formaldehyde and urushiol, also induced the keratinocyte-derived VEGF production. VEGF upregulation by pro-inflammatory stimuli, IFNγ, DNCB or formaldehyde is preceded by the production of IL-8, an acute inflammatory phase cytokine. Lymphangiogenic VEGF-C gene transcription was significantly increased when NHKs were treated with formaldehyde, DNCB or urushiol, while transcription of VEGF-A and VEGF-B did not change. Therefore, the chemical allergen-induced VEGF upregulation is mainly due to the increase in lymphangiogenic VEGF-C transcription in NHKs. These results suggest that keratinocyte-derived VEGF may regulate the lymphangiogenic process during the skin sensitization process of ACD. - Highlights: • Pro-inflammatory cytokines induced VEGF production in normal human keratinocytes (NHKs). • Chemical allergens stimulate NHKs to produce VEGF. • VEGF production is preceded by IL-8 production in NHKs. • IFNγ, DNCB and formaldehyde increase lymphangiogenic VEGF-C gene transcription. • VEGF production in NHKs may be a biomarker for the prediction of potential contact allergens.« less

Microgels produced using microfluidic on-chip polymer blending for controlled released of VEGF encoding lentivectors.

PubMed

Madrigal, Justin L; Sharma, Shonit N; Campbell, Kevin T; Stilhano, Roberta S; Gijsbers, Rik; Silva, Eduardo A

2018-03-15

Alginate hydrogels are widely used as delivery vehicles due to their ability to encapsulate and release a wide range of cargos in a gentle and biocompatible manner. The release of encapsulated therapeutic cargos can be promoted or stunted by adjusting the hydrogel physiochemical properties. However, the release from such systems is often skewed towards burst-release or lengthy retention. To address this, we hypothesized that the overall magnitude of burst release could be adjusted by combining microgels with distinct properties and release behavior. Microgel suspensions were generated using a process we have termed on-chip polymer blending to yield composite suspensions of a range of microgel formulations. In this manner, we studied how alginate percentage and degradation relate to the release of lentivectors. Whereas changes in alginate percentage had a minimal impact on lentivector release, microgel degradation led to a 3-fold increase, and near complete release, over 10 days. Furthermore, by controlling the amount of degradable alginate present within microgels the relative rate of release can be adjusted. A degradable formulation of microgels was used to deliver vascular endothelial growth factor (VEGF)-encoding lentivectors in the chick chorioallantoic membrane (CAM) assay and yielded a proangiogenic response in comparison to the same lentivectors delivered in suspension. The utility of blended microgel suspensions may provide an especially appealing platform for the delivery of lentivectors or similarly sized therapeutics. Genetic therapeutics hold considerable potential for the treatment of diseases and disorders including ischemic cardiovascular diseases. To realize this potential, genetic vectors must be precisely and efficiently delivered to targeted regions of the body. However, conventional methods of delivery do not provide sufficient spatial and temporal control. Here, we demonstrate how alginate microgels provide a basis for developing systems for controlled genetic vector release. We adjust the physiochemical properties of alginate for quicker or slower release, and we demonstrate how combining distinct formulations of microgels can tune the release of the overall composite microgel suspension. These composite suspensions are generated using a straightforward and powerful application of droplet microfluidics which allows for the real-time generation of a composite suspension. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Comparative analysis of COX-2, vascular endothelial growth factor and microvessel density in human renal cell carcinomas.

PubMed

Hemmerlein, B; Galuschka, L; Putzer, N; Zischkau, S; Heuser, M

2004-12-01

Cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) are frequently up-regulated in malignant tumours and play a role in proliferation, apoptosis, angiogenesis and tumour invasion. In the present study, the expression of COX-2 and VEGF in renal cell carcinoma (RCC) was analysed and correlated with the microvessel density (MVD). COX-2 and VEGF were analysed by realtime reverse transcriptase-polymerase chain reaction and immunohistochemistry. The MVD was assessed by CD31 immunohistochemistry. The expression of COX-2 and VEGF was determined in the RCC cell lines A498 and Caki-1 under short-term hypoxia and in multicellular tumour cell aggregates. COX-2 was expressed in RCC by tumour epithelia, endothelia and macrophages in areas of cystic tumour regression and tumour necrosis. COX-2 protein in RCC was not altered in comparison with normal renal tissue. VEGF mRNA was up-regulated in RCC and positively correlated with MVD. RCC with high up-regulation of VEGF mRNA showed weak intracytoplasmic expression of VEGF in tumour cells. Intracytoplasmic VEGF protein expression was negatively correlated with MVD. In RCC with necrosis the MVD was reduced in comparison with RCC without necrosis. A498 RCC cells down-regulated COX-2 and up-regulated VEGF under conditions of hypoxia. In Caki-1 cells COX-2 expression remained stable, whereas VEGF was significantly up-regulated. In multicellular A498 cell aggregates COX-2 and VEGF were up-regulated centrally, whereas no gradient was found in Caki-1 cells. COX-2 and VEGF are potential therapeutic targets because COX-2 and VEGF are expressed in RCC and associated cell populations such as endothelia and monocytes/macrophages.

Serum placental growth factor, vascular endothelial growth factor, soluble vascular endothelial growth factor receptor-1 and -2 levels in periodontal disease, and adverse pregnancy outcomes.

PubMed

Sert, Tuba; Kırzıoğlu, F Yeşim; Fentoğlu, Ozlem; Aylak, Firdevs; Mungan, Tamer

2011-12-01

The aim of this study is the evaluation of levels of serum interleukin (IL)-1β, IL-6, IL-10, tumor necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), placental growth factor (PIGF), and soluble VEGF receptor (sVEGFR)-1 and -2 in the association between periodontal disease and adverse pregnancy outcomes. One hundred and nine mothers, who recently gave birth, and 51 women who were not recently pregnant, aged 18 to 35 years, were included in this study. The mothers were classified as term birth, preterm birth (PTB), and preterm low birth weight (PLBW) in respect to their gestational age and baby's birth weight. The birth mothers were grouped as having gingivitis or periodontitis. The non-pregnant group also included periodontally healthy patients. Venous blood samples were collected to evaluate serum IL-1β, IL-6, IL-10, TNF-α, VEGF, PIGF, and sVEGFR-1 and -2 levels. Mother's weight, education, and income level were significantly associated with pregnancy outcomes. Serum levels of IL-1β, TNF-α, IL-6, VEGF, and sVEGFR-1 and -2 showed an increase in significance when related to pregnancy. Whereas in the PLBW group IL-1β, VEGF, and sVEGFR-2 levels were increased, in the PTB group sVEGFR-1 levels were increased. Additionally, the patients in the PLBW group with periodontitis had higher serum levels of IL-1β, VEGF, sVEGFR-2, and IL-1β/IL-10. The serum levels of IL-1β, VEGF, and sVEGFR-1 and -2 may have a potential effect on the mechanism of the association between periodontal disease and adverse pregnancy outcomes.

Collagen-binding vascular endothelial growth factor attenuates CCl4-induced liver fibrosis in mice

PubMed Central

Wu, Kangkang; Huang, Rui; Wu, Hongyan; Liu, Yong; Yang, Chenchen; Cao, Shufeng; Hou, Xianglin; Chen, Bing; Dai, Jianwu; Wu, Chao

2016-01-01

Vascular endothelial growth factor (VEGF) serves an important role in promoting angiogenesis and tissue regeneration. However, the lack of an effective delivery system that can target this growth factor to the injured site reduces its therapeutic efficacy. Therefore, in the current study, collagen-binding VEGF was constructed by fusing a collagen-binding domain (CBD) to the N-terminal of native VEGF. The CBD-VEGF can specifically bind to collagen which is the major component of the extracellular matrix in fibrotic liver. The anti-fibrotic effects of this novel material were investigated by the carbon tetrachloride (CCl4)-induced liver fibrotic mouse model. Mice were injected with CCl4 intraperitoneally to induce liver fibrosis. CBD-VEGF was injected directly into the liver tissue of mice. The liver tissues were stained with hematoxylin and eosin for general observation or with Masson's trichrome staining for detection of collagen deposition. The hepatic stellate cell activation, blood vessel formation and hepatocyte proliferation were measured by immunohistochemical staining for α-smooth muscle actin, CD31 and Ki67 in the liver tissue. The fluorescent TUNEL assay was performed to evaluate the hepatocyte apoptosis. The present study identified that the CBD-VEGF injection could significantly promote vascularization of the liver tissue of fibrotic mice and attenuate liver fibrosis. Furthermore, hepatocyte apoptosis and hepatic stellate cell activation were attenuated by CBD-VEGF treatment. CBD-VEGF treatment could additionally promote hepatocyte regeneration in the liver tissue of fibrotic mice. Thus, it was suggested that CBD-VEGF may be used as a novel therapeutic intervention for liver fibrosis. PMID:27748931

Vascular endothelial growth factor and the kidney: something of the marvellous.

PubMed

Advani, Andrew

2014-01-01

The vascular endothelial growth factor (VEGF) system is a multifarious network and an exemplar of an intraglomerular signalling pathway. Here, we review recent advances that highlight the subtle nature of the renal VEGF system and its influencers. The VEGF system is no longer considered as a simple paracrine, ligand-receptor interaction under the regulatory control of a soluble 'decoy', soluble fms-like tyrosine kinase-1 (sFLT1). Rather, the abundantly expressed, podocyte-derived VEGF isoform, VEGF-A, is now recognized to mediate both paracrine effects across the filtration barrier and autocrine actions, functioning to preserve the integrity of the cells from which it arises. Autocrine actions of the podocyte VEGF system extend beyond those of the VEGF-A isoform, however, with sFLT1 itself now appreciated as regulating podocyte morphology by binding to lipid microdomains. These and other functions of the VEGF system are profoundly affected by the presence, nature and abundance of influencers both intrinsic and extrinsic to the pathway, the latter most readily exemplified by the role of the cytokine in the diabetic kidney. The glomerular VEGF system plays a delicate, yet critical, role in preserving renal homeostasis. It may be intricate, but 'in all things of nature there is something of the marvellous'.

[Polymorphism in the regulatory regions -С2578A and +C936T of the vascular endothelial growth factor (VEGF-A) gene in Russian women with rheumatoid arthritis].

PubMed

Shevchenko, A V; Prokofyev, V F; Korolev, M A; Banshchikova, N E; Konenkov, V I

To analyze polymorphism in the regulatory regions of the vascular endothelial growth factor (VEGF) gene in female patients with rheumatoid arthritis (RA). The investigation enrolled 257 female patients with RA. A control group consisted of 297 women without chronic diseases. The investigators examined the single-nucleotide polymorphism of VEGF-А2578С in the promoter region (rs699947) and that of VEGF+С936Т 3 in the retranslated region (rs3025039) of the gene. Genotyping was performed by restriction fragment length polymorphism analysis. There was an increase in the frequency of VEGF+936 CT and a reduction in that of the VEGF+936СС genotypes in the seronegative patients as compared to the healthy women. The VEGF+936СС genotype frequency was higher in the patients with seropositive RA than in the subgroup of seronegative patients. The frequency of the VEGF-2578СС genotype was increased in the patients with RA and rheumatoid nodules, as compared to the healthy women. The data presented suggest that the presence of certain VEGF gene variants located in the regulatory regions may reflect the nature of immunopathological mechanisms in RA.

Interplay between VEGF and Nrf2 regulates angiogenesis due to intracranial venous hypertension.

PubMed

Li, Liwen; Pan, Hao; Wang, Handong; Li, Xiang; Bu, Xiaomin; Wang, Qiang; Gao, Yongyue; Wen, Guodao; Zhou, Yali; Cong, Zixiang; Yang, Youqing; Tang, Chao; Liu, Zhengwei

2016-11-21

Venous hypertension(VH) plays an important role in the pathogenesis of cerebral arteriovenous malformations (AVMs) and is closely associated with the HIF-1α/VEGF signaling pathway. Nuclear factor erythroid 2-related factor 2(Nrf2) significantly influences angiogenesis; however, the interplay between Nrf2 and VEGF under VH in brain AVMs remains unclear. Therefore, our study aimed to investigate the interplay between Nrf2 and VEGF due to VH in brain AVMs. Immunohistochemistry indicated that Nrf2 and VEGF were highly expressed in human brain AVM tissues. In vivo, we established a VH model in both wild-type (WT) and siRNA-mediated Nrf2 knockdown rats. VH significantly increased the expression of Nrf2 and VEGF. Loss of Nrf2 markedly inhibited the upregulation of VEGF, as determined by Western blot analysis and qRT-PCR. In vitro, primary brain microvascular endothelial cells (BMECs) were isolated from WT and Nrf2 -/- mice, and a VEGF-Nrf2 positive feed-back loop was observed in BMECs. By trans well assay and angiogenesis assay, Nrf2 knockout significantly inhibited the migration and vascular tube formation of BMECs. These findings suggest that the interplay between Nrf2 and VEGF can contribute to VH-induced angiogenesis in brain AVMs pathogenesis.

Novel Function for Vascular Endothelial Growth Factor Receptor-1 on Epidermal Keratinocytes

PubMed Central

Wilgus, Traci A.; Matthies, Annette M.; Radek, Katherine A.; Dovi, Julia V.; Burns, Aime L.; Shankar, Ravi; DiPietro, Luisa A.

2005-01-01

Vascular endothelial growth factor (VEGF-A), a potent stimulus for angiogenesis, is up-regulated in the skin after wounding. Although studies have shown that VEGF is important for wound repair, it is unclear whether this is based solely on its ability to promote angiogenesis or if VEGF can also promote healing by acting directly on non-endothelial cell types. By immunohistochemistry and reverse transcriptase-polymerase chain reaction, expression of VEGF receptor-1 (VEGFR-1), but not VEGFR-2, was detected in murine keratinocytes during wound repair and in normal human epidermal keratinocytes (NHEKs). The presence of VEGF receptors on NHEKs was verified by binding studies with 125I-VEGF. In vitro, VEGF stimulated the proliferation of NHEKs, an effect that could be blocked by treatment with neutralizing VEGFR-1 antibodies. A role for VEGFR-1 in keratinocytes was also shown in vivo because treatment of excisional wounds with neutralizing VEGFR-1 antibodies delayed re-epithelialization. Treatment with anti-VEGFR-1 antibodies also reduced the number of proliferating keratinocytes at the leading edge of the wound, suggesting that VEGF sends a proliferative signal to these cells. Together, these data describe a novel role for VEGFR-1 in keratinocytes and suggest that VEGF may play several roles in cutaneous wound repair. PMID:16251410

Synergistic Effects of Vascular Endothelial Growth Factor on Bone Morphogenetic Proteins Induced Bone Formation In Vivo: Influencing Factors and Future Research Directions

PubMed Central

Li, Bo; Wang, Hai; Qiu, Guixing; Su, Xinlin

2016-01-01

Vascular endothelial growth factor (VEGF) and bone morphogenetic proteins (BMPs), as key mediators in angiogenesis and osteogenesis, are used in a combined delivery manner as a novel strategy in bone tissue engineering. VEGF has the potential to enhance BMPs induced bone formation. Both gene delivery and material-based delivery systems were incorporated in previous studies to investigate the synergistic effects of VEGF and BMPs. However, their results were controversial due to variation of methods incorporated in different studies. Factors influencing the synergistic effects of VEGF on BMPs induced bone formation were identified and analyzed in this review to reduce confusion on this issue. The potential mechanisms and directions of future studies were also proposed here. Further investigating mechanisms of the synergistic effects and optimizing these influencing factors will help to generate more effective bone regeneration. PMID:28070506

Hepatocellular hypoxia-induced vascular endothelial growth factor expression and angiogenesis in experimental biliary cirrhosis.

PubMed

Rosmorduc, O; Wendum, D; Corpechot, C; Galy, B; Sebbagh, N; Raleigh, J; Housset, C; Poupon, R

1999-10-01

We tested the potential role of vascular endothelial growth factor (VEGF) and of fibroblast growth factor-2 (FGF-2) in the angiogenesis associated with experimental liver fibrogenesis induced by common bile duct ligation in Sprague-Dawley rats. In normal rats, VEGF and FGF-2 immunoreactivities were restricted to less than 3% of hepatocytes. One week after bile duct ligation, hypoxia was demonstrated by the immunodetection of pimonidazole adducts unevenly distributed throughout the lobule. After 2 weeks, hypoxia and VEGF expression were detected in >95% of hepatocytes and coexisted with an increase in periportal vascular endothelial cell proliferation, as ascertained by Ki67 immunolabeling. Subsequently, at 3 weeks the density of von Willebrand-labeled vascular section in fibrotic areas significantly increased. Semiquantitative reverse transcription polymerase chain reaction showed that VEGF(120) and VEGF(164) transcripts, that correspond to secreted isoforms, increased within 2 weeks, while VEGF(188) transcripts remained unchanged. FGF-2 mainly consisting of a 22-kd isoform, according to Western blot, was identified by immunohistochemistry in 49% and 100% of hepatocytes at 3 and 7 weeks, respectively. Our data provide evidence that in biliary-type liver fibrogenesis, angiogenesis is stimulated primarily by VEGF in response to hepatocellular hypoxia while FGF-2 likely contributes to the maintenance of angiogenesis at later stages.

Modulating release of ranibizumab and aflibercept from thiolated chitosan-based hydrogels for potential treatment of ocular neovascularization.

PubMed

Moreno, Miguel; Pow, Poh Yih; Tabitha, Tan Su Teng; Nirmal, Sonali; Larsson, Andreas; Radhakrishnan, Krishna; Nirmal, Jayabalan; Quah, Soo Tng; Geifman Shochat, Susana; Agrawal, Rupesh; Venkatraman, Subbu

2017-08-01

This paper describes the synthesis of thiolated chitosan-based hydrogels with varying degrees of crosslinking that has been utilized to modulate release kinetics of two clinically relevant FDA-approved anti-VEGF protein drugs, ranibizumab and aflibercept. These hydrogels have been fabricated into disc shaped structures for potential use as patches on ocular surface. Protein conformational changes and aggregation after loading and release was evaluated by circular dichroism (CD), steady-state tryptophan fluorescence spectroscopy, electrophoresis and size-exclusion chromatography (SEC). Finally, the capacity of both released proteins to bind to VEGF was tested by ELISA and surface plasmon resonance (SPR) technology. The study demonstrates the versatility of thiolated chitosan-based hydrogels for delivering proteins. The effect of various parameters of the hydrogel on protein release kinetics and mechanism of protein release was studied using the Korsmeyer-Peppas release model. Furthermore, we have studied the stability of released proteins in detail while comparing it with non-entrapped proteins under physiological conditions to understand the effect of formulation conditions on protein stability. The disc-shaped thiolated chitosan-based hydrogels provide a potentially useful platform to deliver ranibizumab and aflibercept for the treatments of ocular diseases such as wet AMD, DME and corneal neovascularization.

Mechanism-related circulating proteins as biomarkers for clinical outcome in patients with unresectable hepatocellular carcinoma receiving sunitinib

PubMed Central

2011-01-01

Background Several proteins that promote angiogenesis are overexpressed in hepatocellular carcinoma (HCC) and have been implicated in disease pathogenesis. Sunitinib has antiangiogenic activity and is an oral multitargeted inhibitor of vascular endothelial growth factor receptors (VEGFRs)-1, -2, and -3, platelet-derived growth factor receptors (PDGFRs)-α and -β, stem-cell factor receptor (KIT), and other tyrosine kinases. In a phase II study of sunitinib in advanced HCC, we evaluated the plasma pharmacodynamics of five proteins related to the mechanism of action of sunitinib and explored potential correlations with clinical outcome. Methods Patients with advanced HCC received a starting dose of sunitinib 50 mg/day administered orally for 4 weeks on treatment, followed by 2 weeks off treatment. Plasma samples from 37 patients were obtained at baseline and during treatment and were analyzed for vascular endothelial growth factor (VEGF)-A, VEGF-C, soluble VEGFR-2 (sVEGFR-2), soluble VEGFR-3 (sVEGFR-3), and soluble KIT (sKIT). Results At the end of the first sunitinib treatment cycle, plasma VEGF-A levels were significantly increased relative to baseline, while levels of plasma VEGF-C, sVEGFR-2, sVEGFR-3, and sKIT were significantly decreased. Changes from baseline in VEGF-A, sVEGFR-2, and sVEGFR-3, but not VEGF-C or sKIT, were partially or completely reversed during the first 2-week off-treatment period. High levels of VEGF-C at baseline were significantly associated with Response Evaluation Criteria in Solid Tumors (RECIST)-defined disease control, prolonged time to tumor progression (TTP), and prolonged overall survival (OS). Baseline VEGF-C levels were an independent predictor of TTP by multivariate analysis. Changes from baseline in VEGF-A and sKIT at cycle 1 day 14 or cycle 2 day 28, and change in VEGF-C at the end of the first off-treatment period, were significantly associated with both TTP and OS, while change in sVEGFR-2 at cycle 1 day 28 was an independent predictor of OS. Conclusions Baseline plasma VEGF-C levels predicted disease control (based on RECIST) and were positively associated with both TTP and OS in this exploratory analysis, suggesting that this VEGF family member may have utility in predicting clinical outcome in patients with HCC who receive sunitinib. Trial registration ClinicalTrials.gov: NCT00247676 PMID:21787417

A stimuli responsive liposome loaded hydrogel provides flexible on-demand release of therapeutic agents.

PubMed

O'Neill, Hugh S; Herron, Caroline C; Hastings, Conn L; Deckers, Roel; Lopez Noriega, Adolfo; Kelly, Helena M; Hennink, Wim E; McDonnell, Ciarán O; O'Brien, Fergal J; Ruiz-Hernández, Eduardo; Duffy, Garry P

2017-01-15

Lysolipid-based thermosensitive liposomes (LTSL) embedded in a chitosan-based thermoresponsive hydrogel matrix (denoted Lipogel) represents a novel approach for the spatiotemporal release of therapeutic agents. The entrapment of drug-loaded liposomes in an injectable hydrogel permits local liposome retention, thus providing a prolonged release in target tissues. Moreover, release can be controlled through the use of a minimally invasive external hyperthermic stimulus. Temporal control of release is particularly important for complex multi-step physiological processes, such as angiogenesis, in which different signals are required at different times in order to produce a robust vasculature. In the present work, we demonstrate the ability of Lipogel to provide a flexible, easily modifiable release platform. It is possible to tune the release kinetics of different drugs providing a passive release of one therapeutic agent loaded within the gel and activating the release of a second LTSL encapsulated agent via a hyperthermic stimulus. In addition, it was possible to modify the drug dosage within Lipogel by varying the duration of hyperthermia. This can allow for adaption of drug dosing in real time. As an in vitro proof of concept with this system, we investigated Lipogels ability to recruit stem cells and then elevate their production of vascular endothelial growth factor (VEGF) by controlling the release of a pro-angiogenic drug, desferroxamine (DFO) with an external hyperthermic stimulus. Initial cell recruitment was accomplished by the passive release of hepatocyte growth factor (HGF) from the hydrogel, inducing a migratory response in cells, followed by the delayed release of DFO from thermosensitive liposomes, resulting in a significant increase in VEGF expression. This delayed release could be controlled up to 14days. Moreover, by changing the duration of the hyperthermic pulse, a fine control over the amount of DFO released was achieved. The ability to trigger the release of therapeutic agents at a specific timepoint and control dosing level through changes in duration of hyperthermia enables sequential multi-dose profiles. This paper details the development of a heat responsive liposome loaded hydrogel for the controlled release of pro-angiogenic therapeutics. Lysolipid-based thermosensitive liposomes (LTSLs) embedded in a chitosan-based thermoresponsive hydrogel matrix represents a novel approach for the spatiotemporal release of therapeutic agents. This hydrogel platform demonstrates remarkable flexibility in terms of drug scheduling and sequencing, enabling the release of multiple agents and the ability to control drug dosing in a minimally invasive fashion. The possibility to tune the release kinetics of different drugs independently represents an innovative platform to utilise for a variety of treatments. This approach allows a significant degree of flexibility in achieving a desired release profile via a minimally invasive stimulus, enabling treatments to be tuned in response to changing symptoms and complications. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Vascular endothelial growth factor and soft tissue sarcomas: tumor expression correlates with grade.

PubMed

Chao, C; Al-Saleem, T; Brooks, J J; Rogatko, A; Kraybill, W G; Eisenberg, B

2001-04-01

Vascular endothelial growth factor (VEGF), an endothelial-specific mitogen overexpressed in various epithelial malignancies is thought to be a potent regulator of angiogenesis. We hypothesized that some soft tissue sarcomas, due to their high propensity for hematogenous metastases (1) would overexpress VEGF, (2) that the degree of expression may represent a significant biologic predictor for disease-specific survival, and (3) that recurrent tumor would express as high or higher VEGF compared with the primary tumor. Selected paraffin-embedded tissue of surgical specimens from 79 patients with soft tissue sarcomas, treated between 1989 and 1995 were stained with a rabbit polyclonal anti-VEGF antibody at a concentration of 2 microg/ml. Slides were assessed for VEGF expression as high or low by two investigators blinded to the clinicopathologic data. Twelve patients had VEGF expression of their primary tumors, and their recurrent tumors were compared. The Fishers' exact test assessed for differences in VEGF expression; survival analyses were performed according to the methods of Kaplan and Meier. Seventy-eight percent (29 of 37) of patients who died of disease had high VEGF expression. However, VEGF expression was not an independent predictor of either overall or disease-free survival. Tumor grade correlated with VEGF expression significantly. For the low-grade tumors, 7 of 13 expressed low VEGF, whereas for high-grade tumors, 53 of 66 expressed high VEGF (P = .016). Seven of the 12 paired tumor samples expressed identical VEGF immunostaining. The majority of high-grade soft tissue sarcomas in this study have high intensity VEGF expression. This finding may provide useful information on individual soft tissue sarcomas and offer the basis for therapeutic and biologic targeting in high-risk patients using anti-angiogenesis strategies. However, in our analysis, after accounting for tumor grade, VEGF does not seem to be an independent predictor of clinical outcome.

Comparative Evaluation of TRAIL, FGF-2 and VEGF-A-Induced Angiogenesis In Vitro and In Vivo

PubMed Central

Cartland, Siân P.; Genner, Scott W.; Zahoor, Amna; Kavurma, Mary M.

2016-01-01

Tumor necrosis-factor-related apoptosis-inducing ligand (TRAIL) has been implicated in angiogenesis; the growth of new blood vessels from an existing vessel bed. Our aim was to compare pro-angiogenic responses of TRAIL, vascular endothelial growth-factor-A (VEGF-A) and fibroblast growth-factor-2 (FGF-2) either separately (10 ng/mL) or in combination, followed by the assessment of proliferation, migration and tubule formation using human microvascular endothelial-1 (HMEC-1) cells in vitro. Angiogenesis was also measured in vivo using the Matrigel plug assay. TRAIL and FGF-2 significantly augmented HMEC-1 cell proliferation and migration, with combination treatment having an enhanced effect on cell migration only. In contrast, VEGF-A did not stimulate HMEC-1 migration at 10 ng/mL. Tubule formation was induced by all three factors, with TRAIL more effective compared to VEGF-A, but not FGF-2. TRAIL at 400 ng/mL, but not VEGF-A, promoted CD31-positive staining into the Matrigel plug. However, FGF-2 was superior, stimulating cell infiltration and angiogenesis better than TRAIL and VEGF-A in vivo. These findings demonstrate that each growth factor is more effective at different processes of angiogenesis in vitro and in vivo. Understanding how these molecules stimulate different processes relating to angiogenesis may help identify new strategies and treatments aimed at inhibiting or promoting dysregulated angiogenesis in people. PMID:27918462

Comparative Evaluation of TRAIL, FGF-2 and VEGF-A-Induced Angiogenesis In Vitro and In Vivo.

PubMed

Cartland, Siân P; Genner, Scott W; Zahoor, Amna; Kavurma, Mary M

2016-12-02

Tumor necrosis-factor-related apoptosis-inducing ligand (TRAIL) has been implicated in angiogenesis; the growth of new blood vessels from an existing vessel bed. Our aim was to compare pro-angiogenic responses of TRAIL, vascular endothelial growth-factor-A (VEGF-A) and fibroblast growth-factor-2 (FGF-2) either separately (10 ng/mL) or in combination, followed by the assessment of proliferation, migration and tubule formation using human microvascular endothelial-1 (HMEC-1) cells in vitro. Angiogenesis was also measured in vivo using the Matrigel plug assay. TRAIL and FGF-2 significantly augmented HMEC-1 cell proliferation and migration, with combination treatment having an enhanced effect on cell migration only. In contrast, VEGF-A did not stimulate HMEC-1 migration at 10 ng/mL. Tubule formation was induced by all three factors, with TRAIL more effective compared to VEGF-A, but not FGF-2. TRAIL at 400 ng/mL, but not VEGF-A, promoted CD31-positive staining into the Matrigel plug. However, FGF-2 was superior, stimulating cell infiltration and angiogenesis better than TRAIL and VEGF-A in vivo. These findings demonstrate that each growth factor is more effective at different processes of angiogenesis in vitro and in vivo. Understanding how these molecules stimulate different processes relating to angiogenesis may help identify new strategies and treatments aimed at inhibiting or promoting dysregulated angiogenesis in people.

VEGF may contribute to macrophage recruitment and M2 polarization in the decidua.

PubMed

Wheeler, Karen C; Jena, Manoj K; Pradhan, Bhola S; Nayak, Neha; Das, Subhendu; Hsu, Chaur-Dong; Wheeler, David S; Chen, Kang; Nayak, Nihar R

2018-01-01

It is increasingly evident that cytokines and growth factors produced in the decidua play a pivotal role in the regulation of the local immune microenvironment and the establishment of pregnancy. One of the major growth factors produced in the decidua is vascular endothelial growth factor (VEGF), which acts not only on endothelial cells, but also on multiple other cell types, including macrophages. We sought to determine whether decidua-derived VEGF affects macrophage recruitment and polarization using human endometrial/decidual tissue samples, primary human endometrial stromal cells (ESCs), and the human monocyte cell line THP1. In situ hybridization was used for assessment of local VEGF expression and immunohistochemistry was used for identification and localization of CD68-positive endometrial macrophages. Macrophage migration in culture was assessed using a transwell migration assay, and the various M1/M2 phenotypic markers and VEGF expression were assessed using quantitative real-time PCR (qRT-PCR). We found dramatic increases in both VEGF levels and macrophage numbers in the decidua during early pregnancy compared to the secretory phase endometrium (non-pregnant), with a significant increase in M2 macrophage markers, suggesting that M2 is the predominant macrophage phenotype in the decidua. However, decidual samples from preeclamptic pregnancies showed a significant shift in macrophage phenotype markers, with upregulation of M1 and downregulation of M2 markers. In THP1 cultures, VEGF treatment significantly enhanced macrophage migration and induced M1 macrophages to shift to an M2 phenotype. Moreover, treatment with conditioned media from decidualized ESCs induced changes in macrophage migration and polarization similar to that of VEGF treatment. These effects were abrogated by the addition of a potent VEGF inhibitor. Together these results suggest that decidual VEGF plays a significant role in macrophage recruitment and M2 polarization, and that inhibition of VEGF signaling may contribute to the shift in macrophage polarity observed in different pregnancy disorders, including preeclampsia.

VEGF may contribute to macrophage recruitment and M2 polarization in the decidua

PubMed Central

Nayak, Neha; Das, Subhendu; Hsu, Chaur-Dong; Wheeler, David S.; Chen, Kang; Nayak, Nihar R.

2018-01-01

It is increasingly evident that cytokines and growth factors produced in the decidua play a pivotal role in the regulation of the local immune microenvironment and the establishment of pregnancy. One of the major growth factors produced in the decidua is vascular endothelial growth factor (VEGF), which acts not only on endothelial cells, but also on multiple other cell types, including macrophages. We sought to determine whether decidua-derived VEGF affects macrophage recruitment and polarization using human endometrial/decidual tissue samples, primary human endometrial stromal cells (ESCs), and the human monocyte cell line THP1. In situ hybridization was used for assessment of local VEGF expression and immunohistochemistry was used for identification and localization of CD68-positive endometrial macrophages. Macrophage migration in culture was assessed using a transwell migration assay, and the various M1/M2 phenotypic markers and VEGF expression were assessed using quantitative real-time PCR (qRT-PCR). We found dramatic increases in both VEGF levels and macrophage numbers in the decidua during early pregnancy compared to the secretory phase endometrium (non-pregnant), with a significant increase in M2 macrophage markers, suggesting that M2 is the predominant macrophage phenotype in the decidua. However, decidual samples from preeclamptic pregnancies showed a significant shift in macrophage phenotype markers, with upregulation of M1 and downregulation of M2 markers. In THP1 cultures, VEGF treatment significantly enhanced macrophage migration and induced M1 macrophages to shift to an M2 phenotype. Moreover, treatment with conditioned media from decidualized ESCs induced changes in macrophage migration and polarization similar to that of VEGF treatment. These effects were abrogated by the addition of a potent VEGF inhibitor. Together these results suggest that decidual VEGF plays a significant role in macrophage recruitment and M2 polarization, and that inhibition of VEGF signaling may contribute to the shift in macrophage polarity observed in different pregnancy disorders, including preeclampsia. PMID:29324807

Investigation of hypoxia-inducible factor-1α in hippocampal sclerosis: a postmortem study.

PubMed

Feast, Alexandra; Martinian, Lillian; Liu, Joan; Catarino, Claudia B; Thom, Maria; Sisodiya, Sanjay M

2012-08-01

Hypoxia-inducible factor-1α (HIF-1α) is involved in critical aspects of cell survival in response to hypoxia and regulates vascular endothelial growth factor (VEGF) expression. Previous experimental and human studies in epilepsy show up-regulation of VEGF following seizures, although expression of HIF-1α as its potential regulator has not been explored. We used a postmortem (PM) series from patients with epilepsy and hippocampal sclerosis (HS) to investigate patterns of expression of HIF-1α and VEGF and their potential contribution to neuroprotection. In 33 PMs (17 cases with unilateral HS, 3 with bilateral HS, 3 with No-HS, and 10 controls), we quantified neuronal immunolabeling for HIF-1α and VEGF in hippocampal subfields. HIF-1α- and VEGF-immunopositive hippocampal neurones were observed in HS, No-HS, and also in control cases; there was no significant difference in overall labeling between epilepsy cases and controls. In positive cases, HIF-1α and VEGF neuronal labeling localized primarily in CA1, CA4, and CA3 subfields in all groups; significantly more positive neurons were seen in the entorhinal cortex in epilepsy cases (p < 0.05). Labeling lateralized to the side of sclerosis in unilateral HS cases, with significant differences between hemispheres (p < 0.05). There was a trend for high HIF-1α labeling scores in patients with Dravet syndrome without HS and sudden unexpected death in epilepsy (SUDEP) cases, and lower scores with long seizure-free periods prior to death. Hippocampal HIF-1α and VEGF labeling showed a significant correlation. There was neuronal colocalization of HIF-1α and VEGF. Regional expression patterns are in keeping with seizure-related activation of HIF-1α and VEGF. The prominent expression in non-HS cases could support an overall neuroprotective effect. Correlation between HIF-1α and VEGF neuronal immunolabeling supports HIF-1α-mediated induction of VEGF in epilepsy. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.

Vascular endothelial growth factor and platelet-derived growth factor are potential angiogenic and metastatic factors in human breast cancer.

PubMed

Anan, K; Morisaki, T; Katano, M; Ikubo, A; Kitsuki, H; Uchiyama, A; Kuroki, S; Tanaka, M; Torisu, M

1996-03-01

Angiogenesis is a prerequisite for tumor growth and metastasis. Tumor angiogenesis may be mediated by several angiogenic factors such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), transforming growth factor-alpha, and basic fibroblast growth factor. Differential mRNA expressions of VEGF, PDGF (A chain), transforming growth factor-alpha and basic fibroblast growth factor in 32 primary invasive breast tumors were examined by reverse transcriptase-polymerase chain reaction. We analyzed relationships between mRNA expressions of these angiogenic factors and the degree of angiogenesis, tumor size, and metastasis. Quantification of angiogenesis was achieved by the immunohistochemical staining of endothelial cells with antibody to CD31. VEGF and PDGF-A mRNAs were expressed more frequently in breast tumors than in nontumor breast tissues, whereas no difference was found in expression frequency of either transforming growth factor-alpha or basic fibroblast growth factor mRNA. Vascular counts in tumors correlated with each expression frequency of VEGF and PDGF-A mRNA. PDGF-A mRNA was expressed more frequently in tumors with lymph node metastasis than in those without metastasis. Expression of VEGF and PDGF mRNAs detected by reverse transcriptase-polymerase chain reaction in breast tumors correlates with tumor-related characteristics of angiogenesis and metastatic potential. Analysis of these mRNAs by reverse transcriptase-polymerase chain reaction may be useful for assessing the biologic behavior of a breast tumor before surgical treatment.

Growth factor-functionalized silk membranes support wound healing in vitro.

PubMed

Bienert, M; Hoss, M; Bartneck, M; Weinandy, S; Böbel, M; Jockenhövel, S; Knüchel, R; Pottbacker, K; Wöltje, M; Jahnen-Dechent, W; Neuss, S

2017-08-16

Chronic wounds represent a serious problem in daily medical routine requiring improved wound care. Silk of the domesticated silkworm (Bombyx mori) has been used to form a variety of biomaterials for medical applications. We genetically engineered B. mori to produce silk functionalized with growth factors to promote wound healing in vitro. In this study FGF-, EGF-, KGF-, PDGF- or VEGF-functionalized silk membranes were compared to native B. mori silk membranes without growth factors for their ability to support wound healing in vitro. All silk membranes were cytocompatible and supported macrophage secretion of neutrophil recruiting factor CXCL1 and monocyte chemoattractant protein 1 (MCP-1). VEGF-functionalized silk significantly outperformed other growth factor-functionalized silk membranes, but not native silk in angiogenesis assays. In addition, EGF- and VEGF-functionalized silk membranes slightly enhanced macrophage adhesion compared to silk without growth factors. In wound healing assays in vitro (reduction of wound lesion), dermal equivalents showed a higher wound healing capacity when covered with EGF-, FGF- or VEGF-functionalized silk membranes compared to native, KGF- or PDGF-functionalized silk membranes. Keratinocyte migration and growth is overstimulated by KGF- and VEGF-functionalized silk membranes. In conclusion, growth factor-functionalized silk membranes prepared from genetically engineered silk worm glands are promising wound dressings for future wound healing therapies.

Pathophysiological consequences of VEGF-induced vascular permeability

NASA Astrophysics Data System (ADS)

Weis, Sara M.; Cheresh, David A.

2005-09-01

Although vascular endothelial growth factor (VEGF) induces angiogenesis, it also disrupts vascular barrier function in diseased tissues. Accordingly, VEGF expression in cancer and ischaemic disease has unexpected pathophysiological consequences. By uncoupling endothelial cell-cell junctions VEGF causes vascular permeability and oedema, resulting in extensive injury to ischaemic tissues after stroke or myocardial infarction. In cancer, VEGF-mediated disruption of the vascular barrier may potentiate tumour cell extravasation, leading to widespread metastatic disease. Therefore, by blocking the vascular permeability promoting effects of VEGF it may be feasible to reduce tissue injury after ischaemic disease and minimize the invasive properties of circulating tumour cells.

Correlation between increasing tissue ischemia and circulating levels of angiogenic growth factors in peripheral artery disease.

PubMed

Jalkanen, Juho; Hautero, Olli; Maksimow, Mikael; Jalkanen, Sirpa; Hakovirta, Harri

2018-04-21

The aim of the present study was to assess the circulating levels of vascular endothelial growth factor (VEGF) and other suggested therapeutic growth factors with the degree of ischemia in patients with different clinical manifestations of peripheral arterial disease (PAD) according to the Rutherford grades. The study cohort consists of 226 consecutive patients admitted to a Department of Vascular Surgery for elective invasive procedures. PAD patients were grouped according to the Rutherford grades after a clinical assessment. Ankle-brachial pressure indices (ABI) and absolute toe pressure (TP) values were measured. Serum levels of circulating VEGF, hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF), and platelet derived growth factor (PDGF) were measured from serum and analysed against Rutherford grades and peripheral hemodynamic measurements. The levels of VEGF (P = 0.009) and HGF (P < 0.001) increased significantly as the ischaemic burden became more severe according to the Rutherford grades. PDGF behaved in opposite manner and declined along increasing Rutherford grades (P = 0.004). A significant, inverse correlations between Rutherford grades was detected as follows; VEGF (Pearson's correlation = 0.183, P = 0.004), HGF (Pearson's correlation = 0.253, P < 0.001), bFGF (Pearson's correlation = 0.169, P = 0.008) and PDGF (Pearson's correlation = 0.296, P < 0.001). In addition, VEGF had a clear direct negative correlation with ABI (Pearson's correlation -0.19, P = 0.009) and TP (Pearson's correlation -0.20, P = 0.005) measurements. Our present observations show that the circulating levels of VEGF and other suggested therapeutic growth factors are significantly increased along with increasing ischemia. These findings present a new perspective to anticipated positive effects of gene therapies utilizing VEGF, HGF, and bFGF, because the levels of these growth factors are endogenously high in end-stage PAD. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nicotine promotes vascular endothelial growth factor secretion by human trophoblast cells under hypoxic conditions and improves the proliferation and tube formation capacity of human umbilical endothelial cells.

PubMed

Zhao, Hongbo; Wu, Lanxiang; Wang, Yahui; Zhou, Jiayi; Li, Ruixia; Zhou, Jiabing; Wang, Zehua; Xu, Congjian

2017-04-01

Pre-eclampsia, characterized as defective uteroplacental vascularization, remains the major cause of maternal and fetal mortality and morbidity. Previous epidemiological studies demonstrated that cigarette smoking reduced the risk of pre-eclampsia. However, the molecular mechanism remains elusive. In the present study, it is demonstrated that a low dose of nicotine decreased soluble vascular endothelial growth factor receptor 1 (sFlt1) secretion in human trophoblast cells under hypoxic conditions. Nicotine was then observed to promote vascular endothelial growth factor (VEGF) secretion by reducing sFlt1 secretion and increasing VEGF mRNA transcription. Further data showed that nicotine enhanced hypoxia-mediated hypoxia-inducible factor-1α (HIF-1α) expression and HIF-1α small interfering RNA abrogated nicotine-induced VEGF secretion, indicating that HIF-1α may be responsible for nicotine-mediated VEGF transcription under hypoxic conditions. Moreover, conditioned medium from human trophoblast cells treated with nicotine under hypoxic conditions promoted the proliferation and tube formation capacity of human umbilical endothelial cells (HUVEC) by promoting VEGF secretion. These findings indicate that nicotine may promote VEGF secretion in human trophoblast cells under hypoxic conditions by reducing sFlt1 secretion and up-regulating VEGF transcription and improve the proliferation and tube formation of HUVEC cells, which may contribute to elucidate the protective effect of cigarette smoking against pre-eclampsia. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

VEGF and Ki-67 Overexpression in Predicting Poor Overall Survival in Adenoid Cystic Carcinoma.

PubMed

Park, Seongyeol; Nam, Soo Jeong; Keam, Bhumsuk; Kim, Tae Min; Jeon, Yoon Kyung; Lee, Se-Hoon; Hah, J Hun; Kwon, Tack-Kyun; Kim, Dong-Wan; Sung, Myung-Whun; Heo, Dae Seog; Bang, Yung-Jue

2016-04-01

The purpose of this study was to evaluate potential prognostic factors in patients with adenoid cystic carcinoma (ACC). A total of 68 patients who underwent curative surgery and had available tissue were enrolled in this study. Their medical records and pathologic slides were reviewed and immunohistochemistry for basic fibroblast growth factor, fibroblast growth factor receptor (FGFR) 2, FGFR3, c-kit, Myb proto-oncogene protein, platelet-derived growth factor receptor beta, vascular endothelial growth factor (VEGF), and Ki-67 was performed. Univariate and multivariate analysis was performed for determination of disease-free survival (DFS) and overall survival (OS). In univariate analyses, primary site of nasal cavity and paranasal sinus (p=0.022) and Ki-67 expression of more than 7% (p=0.001) were statistically significant factors for poor DFS. Regarding OS, perineural invasion (p=0.032), high expression of VEGF (p=0.033), and high expression of Ki-67 (p=0.007) were poor prognostic factors. In multivariate analyses, primary site of nasal cavity and paranasal sinus (p=0.028) and high expression of Ki-67 (p=0.004) were independent risk factors for poor DFS, and high expression of VEGF (p=0.011) and Ki-67 (p=0.011) showed independent association with poor OS. High expression of VEGF and Ki-67 were independent poor prognostic factors for OS in ACC.

The endocrine-gland-derived vascular endothelial growth factor (EG-VEGF)/prokineticin 1 and 2 and receptor expression in human prostate: Up-regulation of EG-VEGF/prokineticin 1 with malignancy.

PubMed

Pasquali, Daniela; Rossi, Valentina; Staibano, Stefania; De Rosa, Gaetano; Chieffi, Paolo; Prezioso, Domenico; Mirone, Vincenzo; Mascolo, Massimo; Tramontano, Donatella; Bellastella, Antonio; Sinisi, Antonio Agostino

2006-09-01

A new family of angiogenic factors named endocrine-gland-derived vascular endothelial growth factors (EG-VEGF)/prokineticins (PK) have been recently described as predominantly expressed in steroidogenic tissues. Whether the normal and malignant epithelial prostate cells and tissues express EG-VEGF/PK1 and PK2 and their receptors is still unknown. We studied the expression of EG-VEGF/PK1 and PK2 and their receptors (PK-R1 and PK-R2) in human prostate and their involvement in cancer. Using immunohistochemistry, Western blot, and RT-PCR, we determined the expression of EG-VEGF/PK1 in normal prostate (NP) and malignant prostate tissues (PCa), in epithelial cell primary cultures from normal prostate (NPEC) and malignant prostate (CPEC) and in a panel of prostate cell lines. In NPEC, CPEC, and in EPN, a nontransformed human prostate epithelial cell line, EG-VEGF/PK1, PK2, PK-R1, and PK-R2 mRNA levels were evaluated by quantitative RT-PCR. EG-VEGF/PK1 transcript was found in PCa, in CPEC, in EPN, and in LNCaP, whereas it was detected at low level in NP and in NPEC. EG-VEGF/PK1 was absent in androgen-independent PC3 and DU-145 cell lines. Immunochemistry confirmed that EG-VEGF/PK1 protein expression was restricted to hyperplastic and malignant prostate tissues, localized in the glandular epithelial cells, and progressively increased with the prostate cancer Gleason score advancement. EG-VEGF/PK1 and PK2 were weakly expressed in NPEC and EPN. On the other hand, their transcripts were highly detected in CPEC. PK-R1 and PK-R2 were found in NPEC, EPN, and CPEC. Interestingly, CPEC showed a significantly (P < 0.05) higher expression of EG-VEGF/PK1, PK2, PK-R1, and PK-R2 compared with NPEC and EPN. We demonstrated that PKs and their receptors are expressed in human prostate and that their levels increased with prostate malignancy. It may imply that EG-VEGF/PK1 could be involved in prostate carcinogenesis, probably regulating angiogenesis. Thus, the level of EG-VEGF/PK1 could be useful for prostate cancer outcome evaluation and as a target for prostate cancer treatment in the future.

Local over-expression of VEGF-DΔNΔC in the uterine arteries of pregnant sheep results in long-term changes in uterine artery contractility and angiogenesis.

PubMed

Mehta, Vedanta; Abi-Nader, Khalil N; Shangaris, Panicos; Shaw, S W Steven; Filippi, Elisa; Benjamin, Elizabeth; Boyd, Michael; Peebles, Donald M; Martin, John; Zachary, Ian; David, Anna L

2014-01-01

The normal development of the uteroplacental circulation in pregnancy depends on angiogenic and vasodilatory factors such as vascular endothelial growth factor (VEGF). Reduced uterine artery blood flow (UABF) is a common cause of fetal growth restriction; abnormalities in angiogenic factors are implicated. Previously we showed that adenovirus (Ad)-mediated VEGF-A165 expression in the pregnant sheep uterine artery (UtA) increased nitric oxide synthase (NOS) expression, altered vascular reactivity and increased UABF. VEGF-D is a VEGF family member that promotes angiogenesis and vasodilatation but, in contrast to VEGF-A, does not increase vascular permeability. Here we examined the effect of Ad.VEGF-DΔNΔC vector encoding a fully processed form of VEGF-D, on the uteroplacental circulation. UtA transit-time flow probes and carotid artery catheters were implanted in mid-gestation pregnant sheep (n = 5) to measure baseline UABF and maternal haemodynamics respectively. 7-14 days later, after injection of Ad.VEGF-DΔNΔC vector (5×10(11) particles) into one UtA and an Ad vector encoding β-galactosidase (Ad.LacZ) contralaterally, UABF was measured daily until scheduled post-mortem examination at term. UtAs were assessed for vascular reactivity, NOS expression and endothelial cell proliferation; NOS expression was studied in ex vivo transduced UtA endothelial cells (UAECs). At 4 weeks post-injection, Ad.VEGF-DΔNΔC treated UtAs showed significantly lesser vasoconstriction (Emax144.0 v/s 184.2, p = 0.002). There was a tendency to higher UABF in Ad.VEGF-DΔNΔC compared to Ad.LacZ transduced UtAs (50.58% v/s 26.94%, p = 0.152). There was no significant effect on maternal haemodynamics. An increased number of proliferating endothelial cells and adventitial blood vessels were observed in immunohistochemistry. Ad.VEGF-DΔNΔC expression in cultured UAECs upregulated eNOS and iNOS expression. Local over-expression of VEGF-DΔNΔC in the UtAs of pregnant mid-gestation sheep reduced vasoconstriction, promoted endothelial cell proliferation and showed a trend towards increased UABF. Studies in cultured UAECs indicate that VEGF-DΔNΔC may act in part through upregulation of eNOS and iNOS.

Gene expression patterns of vascular endothelial growth factor (VEGF-A) in human placenta from pregnancies with intrauterine growth restriction.

PubMed

Szentpéteri, Imre; Rab, Attila; Kornya, László; Kovács, Péter; Joó, József Gábor

2013-07-01

In this study, we describe changes in gene expression pattern of vascular endothelial growth factor (VEGF)-A in human placenta obtained from pregnancies with intrauterine growth restriction using placenta from normal pregnancies as control. We compared gene expression of VEGF-A in placental samples from Intrauterine growth restriction (IUGR) pregnancies versus placenta obtained from normal pregnancies. Among potential confounders, important clinical informations were also analyzed. In the IUGR group, the VEGF-A gene was overexpressed compared to the normal pregnancy group (Ln 2(α)β-actin: 1.32; Ln 2(α)GADPH: 1.56). There was no correlation between the degree of growth restriction and VEGF-A gene expression (Ln 2(α)(0-5)percentile: 0.58; Ln 2(α)(5-10)percentile: 0.64). Within the IUGR group, there was a trend toward a positive correlation between placental VEGF-A gene activity and gestational age at delivery (Ln 2(α)< 33 weeks: 1.09; Ln 2(α)33-37 weeks: 1.27; Ln 2(α)> 37 weeks: 1.35). Our findings suggest that the increase in placental expression of the VEGF-A gene and the resultant stimulation of angiogenesis are a response to hypoxic environment developing in the placental tissue in IUGR. Thus, it appears to be a secondary event rather than a primary factor in the development of IUGR There is a trend toward a positive correlation between gestational age and placental VEGF-A gene activity.

Smad4 Inhibits VEGF-A and VEGF-C Expressions via Enhancing Smad3 Phosphorylation in Colon Cancer.

PubMed

Li, Xuemei; Li, Xinlei; Lv, Xiaohong; Xiao, Jianbing; Liu, Baoquan; Zhang, Yafang

2017-09-01

Smad4 is a critical factor in the TGF-β pathway and is involved in tumor progression and metastasis, but the role of Smad4 in colon cancer cells is unclear. The aim of this study is to explore the effect and the underlying mechanism of Smad4 on the growth, migration and apoptosis of colon cancer cells as well as vascular endothelial growth factor (VEGF)-A and VEGF-C secreted by these cells. In this study, we showed that Smad4, VEGF-A, and VEGF-C are independent prognostic factors of colon cancer, and Smad4 expression was negatively correlated with VEGF-A and -C in samples. We found that Smad4 mRNA and protein levels in colon cancer cells, particularly in HCT-116 cells, were significantly lower than those in the human intestinal epithelial cell line (HIEC). Smad4 overexpression promoted tumor cell apoptosis, inhibited VEGF-A and -C expression in vitro and in vivo, but had no effect on cell proliferation and migration. Tail vein injection of the virus inhibited xenograft growth in nude mice. Importantly, we also demonstrated that Smad4 could increase the phosphorylation level of Smad3, but not Smad2, which may be one of the mechanisms underlying these effects of Smad4 in colon cancer. Therefore, Smad4 may be a new target for the treatment of colon cancer. Anat Rec, 300:1560-1569, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Inhibition of TGF-β Signaling in SHED Enhances Endothelial Differentiation.

PubMed

Xu, J G; Gong, T; Wang, Y Y; Zou, T; Heng, B C; Yang, Y Q; Zhang, C F

2018-02-01

Low efficiency of deriving endothelial cells (ECs) from adult stem cells hampers their utilization in tissue engineering studies. The purpose of this study was to investigate whether suppression of transforming growth factor beta (TGF-β) signaling could enhance the differentiation efficiency of dental pulp-derived stem cells into ECs. We initially used vascular endothelial growth factor A (VEGF-A) to stimulate 2 dental pulp-derived stem cells (dental pulp stem cells and stem cells from human exfoliated deciduous teeth [SHED]) and compared their differentiation capacity into ECs. We further evaluated whether the vascular endothelial growth factor receptor I (VEGF-RI)-specific ligand placental growth factor-1 (PlGF-1) could mediate endothelial differentiation. Finally, we investigated whether the TGF-β signaling inhibitor SB-431542 could enhance the inductive effect of VEGF-A on endothelial differentiation, as well as the underlying mechanisms involved. ECs differentiated from dental pulp-derived stem cells exhibited the typical phenotypes of primary ECs, with SHED possessing a higher endothelial differentiation potential than dental pulp stem cells. VEGFR1-specific ligand-PLGF exerted a negligible effect on SHED-ECs differentiation. Compared with VEGF-A alone, the combination of VEGF-A and SB-431542 significantly enhanced the endothelial differentiation of SHED. The presence of SB-431542 inhibited the phosphorylation of Suppressor of Mothers Against Decapentaplegic 2/3 (SMAD2/3), allowing for VEGF-A-dependent phosphorylation and upregulation of VEGFR2. Our results indicate that the combination of VEGF-A and SB-431542 could enhance the differentiation of dental pulp-derived stem cells into endothelial cells, and this process is mediated through enhancement of VEGF-A-VEGFR2 signaling and concomitant inhibition of TGF-β-SMAD2/3 signaling.

PACAP and VIP regulate hypoxia-inducible factors in neuroblastoma cells exposed to hypoxia.

PubMed

Maugeri, Grazia; D'Amico, Agata Grazia; Rasà, Daniela Maria; Saccone, Salvatore; Federico, Concetta; Cavallaro, Sebastiano; D'Agata, Velia

2018-06-01

Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) are two related peptides acting as neurotransmitters/neuromodulators in central and peripheral nervous system. They are also involved in cancer showing a controversial role. Particulary, they are implicated in neuroblastoma differentiation (NB). This pediatric tumor can evolve to a malignant metastatic disease or spontaneously regress towards a benign form, known as ganglioneuroblastoma/ganglioneuroma. A negative hallmark of neoplasia progression is represented by hypoxic microenvironment. Low oxygen tension induces activation of hypoxia-inducible factors (HIFs) promoting cells proliferation and metastasis formation. Moreover, HIFs trigger vascular endothelial growth factor (VEGF) release favouring high-risk NB phenotype development. In the present work, we have investigated for the first time, if PACAP and VIP interfere with NB differentiation through modulation of hypoxic/angiogenic process. To this end, we analyzed their effect in malignant undifferentiated and all-trans retinoic acid (RA) differentiated SH-SY5Y cells, representing the benign form of this tumor. Our results have suggested tha both peptides, but predominantly VIP, induce NB differentiation into benign form by regulating HIFs, VEGF and VEGFRs expression and distribution. All these data give new insight regarding PACAP/VIP regulatory role in NB progression. Copyright © 2018 Elsevier Ltd. All rights reserved.

Induction of vascular endothelial growth factor expression in human pulp fibroblasts stimulated with black-pigmented Bacteroides.

PubMed

Yang, L-C; Tsai, C-H; Huang, F-M; Su, Y-F; Lai, C-C; Liu, C-M; Chang, Y-C

2004-09-01

To investigate the effect of black-pigmented Bacteroides on the expression of vascular endothelial growth factor (VEGF) gene in human pulp fibroblasts. The supernatants of Porphyromonas endodontalis, Porphyromonas gingivalis and Prevotella intermedia were used to evaluate VEGF gene expression in human pulp fibroblasts. The levels of mRNAs were measured by the quantitative reverse-transcriptase polymerase chain reaction analysis. Black-pigmented Bacteroides induced significantly high levels of VEGF mRNA gene expression in human pulp fibroblasts (P < 0.05). In addition, the expression of VEGF depended on the bacteria tested. Black-pigmented Bacteroides may be involved in developing pulpal disease through the stimulation of VEGF production that would lead to the expansion of the vascular network coincident to progression of the inflammation.

[Transcription factors NF-kB, HIF-1, HIF-2, growth factor VEGF, VEGFR2 and carboanhydrase IX mRNA and protein level in the development of kidney cancer metastasis].

PubMed

Spirina, L V; Usynin, Y A; Yurmazov, Z A; Slonimskaya, E M; Kolegova, E S; Kondakova, I V

2017-01-01

Here, we have investigated the participation of nuclear factors NF-kB, HIF-1 and HIF-2, VEGF, VEGFR2, and carboanhydrase IX in clear-cell renal cancer. We have determined the expression and protein level of transcription factors, VEGF, VEGFR2, and carboanhydrase IX in tumor and normal tissues of 30 patients with kidney cancer. The Real-Time PCR and ELISA were used in the study. The low levels of HIF-1 mRNA expression associated with high levels of HIF-1 protein were also associated with metastasis. The expression levels of VEGF, VEGFR2, and their protein levels are increased in primary tumors of patients with disseminated kidney cancer compared to nonmetastatic cancer. No correlation was revealed between the content of mRNA and encoded proteins in the kidney cancer tissues. The changes in the ratios of mRNA levels and the respective proteins (HIF-1α, HIF-2, NF-kB, VEGF, VEGFR2, and carboanhydrase IX) may contribute to kidney-cancer metastasis.

Expression of vascular endothelial growth factor does not promote transformation but confers a growth advantage in vivo to Chinese hamster ovary cells.

PubMed Central

Ferrara, N; Winer, J; Burton, T; Rowland, A; Siegel, M; Phillips, H S; Terrell, T; Keller, G A; Levinson, A D

1993-01-01

Vascular endothelial growth factor (VEGF) is a mitogen with a specificity for endothelial cells in vitro and an angiogenic inducer in vivo. We tested the hypothesis that VEGF may confer on expressing cells a growth advantage in vivo. Dihydrofolatereductase--Chinese hamster ovary cells were transfected with expression vectors which direct the constitutive synthesis of VEGF. Neither the expression nor the exogenous administration of VEGF stimulated anchorage-dependent or anchorage-independent growth of Chinese hamster ovary cells in vitro. However, VEGF-expressing clones, unlike control cells, demonstrated an ability to proliferate in nude mice. Histologic examination revealed that the proliferative lesions were compact, well vascularized, and nonedematous. Ultrastructural analysis revealed that capillaries within the lesions were of the continuous type. These findings indicate that the expression of VEGF may confer on cells the ability to grow in vivo in the absence of transformation by purely paracrine mechanisms. Since VEGF is a widely distributed protein, this property may have relevance for a variety of physiological and pathological proliferative processes. Images PMID:8423215

Immunohistochemical expression of vegf and her-2 proteins in osteosarcoma biopsies

PubMed Central

Becker, Ricardo Gehrke; Galia, Carlos Roberto; Morini, Sandra; Viana, Cristiano Ribeiro

2013-01-01

OBJECTIVES: To identify the prevalence of erbB-2 and vascular endothelial growth factor (VEGF) in osteosarcoma biopsies and to correlate them with possible prognosis factors. METHODS: Retrospective study conducted at the Hospital do Câncer de Barretos-SP including 27 osteosarcoma biopsies immunohistochemically stained for VEGF and erbB-2. The pathological characteristics were collected from medical records of patients to correlate with markers. RESULTS: In 27 biopsies, four overexpressed VEGF and three overexpressed erbB-2. Two thirds of patients had no metastases. Almost all patients with overexpression of VEGF showed metastases. Overexpression of erbB-2 was inversely related to the presence of metastases. There was no significant association between markers and prognosis. CONCLUSION: We identified a low prevalence of erbB-2 and VEGF in the sample. There was no significant association between overexpression of markers and pathological features. A larger sample and a longer follow-up, in addition to using new laboratory techniques can determine the real expression of VEGF and erbB-2 and its role in osteosarcoma. Level of Evidence III, Case-Control Study. PMID:24453675

Imaging vascular endothelial growth factor (VEGF) receptors in turpentine-induced sterile thigh abscesses with radiolabeled single-chain VEGF.

PubMed

Levashova, Zoia; Backer, Marina; Backer, Joseph M; Blankenberg, Francis G

2009-12-01

Angiogenesis plays a central role in the pathogenesis of chronic inflammatory disorders. Vascular endothelial growth factor (VEGF) and its receptors are the most important regulators of angiogenesis. We wished to determine whether labeled forms of single-chain VEGF (scVEGF) could be used to image VEGF receptors in a well-characterized model of sterile soft-tissue inflammation induced by intramuscular injection of turpentine. Anesthetized adult male Swiss-Webster mice received a 20-microL intramuscular injection of turpentine into the right thigh. At 4, 7, or 10 d later, groups of 3-5 mice were injected via the tail vein with 50 microg of either scVEGF that had been site specifically labeled with Cy5.5 (scVEGF/Cy) or inactivated scVEGF/Cy (inVEGF/Cy) and then examined by fluorescence imaging. At 3, 4, 6, 7, 9, 10, or 12 d, additional groups of 3-5 mice were injected via the tail vein with 74-111 MBq of (99m)Tc-scVEGF (or (99m)Tc-inVEGF) and then examined by SPECT imaging. On days 3 through 10, both forms of scVEGF (scVEGF/Cy and (99m)Tc-scVEGF) showed significantly higher uptake (P < 0.05) in the right (abscessed) thigh than in the contralateral thigh (and higher uptake than the inactivated tracer). Peak uptake occurred on day 7 (3.67 +/- 1.79 [ratio of uptake in abscessed thigh to uptake in normal thigh, mean +/- SD] and 0.72 +/- 0.01 for scVEGF/Cy and inVEGF/Cy, respectively, and 3.49 +/- 1.22 and 1.04 +/- 0.41 for (99m)Tc-scVEGF and (99m)Tc-inVEGF, respectively) and slowly decreased thereafter. Autoradiography revealed peak tracer uptake in the thick irregular angiogenic rim of the abscess cavity on day 9 (5.83 x 10(-7) +/- 9.22 x 10(-8) and 5.85 x 10(-8) +/- 5.95 x 10(-8) percentage injected dose per pixel for (99m)Tc-scVEGF and (99m)Tc-inVEGF, respectively); in comparison, a thin circumscribed rim of uptake was seen with (99m)Tc-inVEGF. Immunostaining revealed that VEGFR-2 (VEGF receptor) colocalized with CD31 (endothelial cell marker) at all time points in the abscess rim, whereas F4/80 (macrophage) immunostaining reached a maximum at day 7 and decreased by day 10. The uptake of scVEGF in turpentine-induced abscesses was specific and directly related to VEGFR-2 expression in the neovasculature of the angiogenic rim. Peak tracer uptake coincided with maximum macrophage infiltration, suggesting that scVEGF imaging may be useful for the detection, localization, and monitoring of chronic inflammation in bone, joints, or soft tissues.

EG-VEGF controls placental growth and survival in normal and pathological pregnancies: case of fetal growth restriction (FGR).

PubMed

Brouillet, S; Murthi, P; Hoffmann, P; Salomon, A; Sergent, F; De Mazancourt, P; Dakouane-Giudicelli, M; Dieudonné, M N; Rozenberg, P; Vaiman, D; Barbaux, S; Benharouga, M; Feige, J-J; Alfaidy, N

2013-02-01

Identifiable causes of fetal growth restriction (FGR) account for 30 % of cases, but the remainders are idiopathic and are frequently associated with placental dysfunction. We have shown that the angiogenic factor endocrine gland-derived VEGF (EG-VEGF) and its receptors, prokineticin receptor 1 (PROKR1) and 2, (1) are abundantly expressed in human placenta, (2) are up-regulated by hypoxia, (3) control trophoblast invasion, and that EG-VEGF circulating levels are the highest during the first trimester of pregnancy, the period of important placental growth. These findings suggest that EG-VEGF/PROKR1 and 2 might be involved in normal and FGR placental development. To test this hypothesis, we used placental explants, primary trophoblast cultures, and placental and serum samples collected from FGR and age-matched control women. Our results show that (1) EG-VEGF increases trophoblast proliferation ([(3)H]-thymidine incorporation and Ki67-staining) via the homeobox-gene, HLX (2) the proliferative effect involves PROKR1 but not PROKR2, (3) EG-VEGF does not affect syncytium formation (measurement of syncytin 1 and 2 and β hCG production) (4) EG-VEGF increases the vascularization of the placental villi and insures their survival, (5) EG-VEGF, PROKR1, and PROKR2 mRNA and protein levels are significantly elevated in FGR placentas, and (6) EG-VEGF circulating levels are significantly higher in FGR patients. Altogether, our results identify EG-VEGF as a new placental growth factor acting during the first trimester of pregnancy, established its mechanism of action, and provide evidence for its deregulation in FGR. We propose that EG-VEGF/PROKR1 and 2 increases occur in FGR as a compensatory mechanism to insure proper pregnancy progress.

Identification and characterization of VEGF and FGF from Hydra.

PubMed

Krishnapati, Lakshmi-Surekha; Ghaskadbi, Surendra

2013-01-01

Vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) play important roles in the formation of the blood vascular system and in axon guidance, nervous system development and function. Here, we report isolation and characterization of VEGF and FGF homologues from Hydra vulgaris Ind-Pune, a Cnidarian which exhibits an organized nervous system and primitive epithelio-muscular cells. VEGF expression was prominent in the endoderm of the peduncle region and tentacles, as evident from in situ hybridization of whole polyps and its transverse sections. High levels of FGF were detected in the ectoderm of the budding region. The expression of VEGF in endodermal and FGF in interstitial cells was confirmed using sf-1 hydra, a temperature-sensitive mutant strain of Hydra magnipapillata. Tissue-specific expression of VEGF and FGF was confirmed by semi quantitative RT-PCR for ectodermal and endodermal tissues in H. vulgaris Ind-Pune. Treatment with SU5416, a specific inhibitor of the VEGF receptor, did not affect the whole polyp, but did delay both budding and head regeneration, suggesting a possible role of VEGF in nerve cell development, tube formation and/or in branching. FGF expression in the ectoderm of budding region, where the majority of interstitial stem cells reside suggests its role in interstitial stem cell maintenance. Further, activation of canonical Wnt signalling with the glycogen synthase kinase-3β (GSK-3β) inhibitor alsterpaullone caused down-regulation of VEGF and FGF, suggesting an antagonistic relationship between the Wnt and VEGF/FGF pathways. Our results indicate that VEGF and FGF evolved early in evolution, before the development of the blood vascular system, and open up the possibility of elucidating the evolutionarily ancient functions of VEGF and FGF.

Intraocular Vascular Endothelial Growth Factor Levels in Pachychoroid Neovasculopathy and Neovascular Age-Related Macular Degeneration.

PubMed

Hata, Masayuki; Yamashiro, Kenji; Ooto, Sotaro; Oishi, Akio; Tamura, Hiroshi; Miyata, Manabu; Ueda-Arakawa, Naoko; Takahashi, Ayako; Tsujikawa, Akitaka; Yoshimura, Nagahisa

2017-01-01

To investigate the difference in intraocular vascular endothelial growth factor (VEGF) concentration between pachychoroid neovasculopathy and neovascular age-related macular degeneration (nAMD) and its associations with responses to three monthly anti-VEGF injections as an initial treatment for the two conditions. This study included nine eyes with treatment-naïve pachychoroid neovasculopathy and 21 eyes with treatment-naïve nAMD. Before the initial intravitreal anti-VEGF injection, aqueous humor samples were collected and the concentration of VEGF was measured using enzyme-linked immunosorbent assay. The concentration was compared between the two conditions, and its associations with responses to anti-VEGF therapy were investigated. The mean VEGF concentration in pachychoroid neovasculopathy was significantly lower than that in nAMD (63.4 ± 17.8 pg/ml and 89.8 ± 45.0 pg/ml, respectively; P = 0.035). The VEGF concentration was associated with the presence or absence of drusen (β = 0.503, P = 0.004). After anti-VEGF therapy, 6 (66.7%) of 9 eyes with pachychoroid neovasculopathy and 17 (81.0%) of 21 eyes with nAMD achieved dry macula (P = 0.640). Dry macula at 3 months and 12 months was significantly associated with a low VEGF concentration in pachychoroid neovasculopathy (P = 0.013 and P = 0.042, respectively), but not in nAMD (P = 0.108 and P = 0.219). The mean VEGF concentration in pachychoroid neovasculopathy was lower than that in nAMD, suggesting that the way in which VEGF is involved in angiogenesis may differ between pachychoroid neovasculopathy and nAMD.

Severity-Related Increase and Cognitive Correlates of Serum VEGF Levels in Alzheimer's Disease ApoE4 Carriers.

PubMed

Alvarez, X Anton; Alvarez, Irene; Aleixandre, Manuel; Linares, Carlos; Muresanu, Dafin; Winter, Stefan; Moessler, Herbert

2018-01-01

Vascular endothelial growth factor (VEGF) is an angioneurin involved in the regulation of vascular and neural functions relevant for the pathophysiology of Alzheimer's disease (AD), but the influence of AD severity and ApoE4 status on circulating VEGF and its relationship with cognition has not been investigated. We assessed serum VEGF levels and cognitive performance in AD, amnestic mild cognitive impairment (MCI), and control subjects. VEGF levels were higher in AD patients than in MCI cases and controls (p < 0.05) and showed a progressive increase with clinical severity in the whole study population (p < 0.01). Among AD patients, severity-related VEGF elevations were significant in ApoE4 carriers (p < 0.05), but not in non-carriers. Increased VEGF levels were associated with disease severity and showed mild correlations with cognitive impairment that were only consistent for the ADAS-cog+ items remembering test instructions (memory) and maze task (executive functions) in the group of AD patients (p < 0.05). On the other hand, higher VEGF values were related to better memory and language performance in ApoE4 carriers with moderately-severe AD. According to these results showing severity- and ApoE4-related differences in serum VEGF and its cognitive correlates, it is suggested that increases in VEGF levels might represent an endogenous response driven by pathological factors and could entail cognitive benefits in AD patients, particularly in ApoE4 carriers. Our findings support the notion that VEGF constitutes a relevant molecular target to be further explored in AD pathology and therapy.

NGF/anti-VEGF combined exposure protects RCS retinal cells and photoreceptors that underwent a local worsening of inflammation.

PubMed

Rocco, Maria Luisa; Balzamino, Bijorn Omar; Esposito, Graziana; Petrella, Carla; Aloe, Luigi; Micera, Alessandra

2017-03-01

Our previous study highlighted the potential nerve growth factor (NGF) effect on damaged photoreceptors from a rat model of spontaneous Retinitis Pigmentosa (RP). Herein, we tested the combined NGF/anti-vascular endothelial growth factor (αVEGF) effect on cultured retinal cells isolated from Royal College of Surgeons (RCS) rats receiving an intravitreal VEGF injection (iv-VEGF) to exacerbate retinal inflammation/neovascularization. RCS (n = 75) rats were equally grouped as untreated (n = 25), iv-saline (single saline intravitreal injection; n = 25) and iv-VEGF (single VEGF intravitreal injection; n = 25). Morphological and biochemical analysis or in vitro stimulations with the biomolecular investigation were carried out on explanted retinas. Isolated retinal cells were treated with NGF and αVEGF, either alone or in combination, for 6 days and cells were harvested for morphological and biomolecular analyses. Infiltrating inflammatory cells were detected in iv-VEGF exposed RCS retinas, indicative of exacerbated inflammation and neovascularization. In cell cultures, NGF/αVEGF significantly increased retinal cell survival as well as rhodopsin expression and neurite outgrowth in photoreceptors. Particularly, NGF/αVEGF upregulated Bcl-2 mRNA, downregulated Bax mRNA, upregulated trkA NGFR mRNA and finally upregulated both NGF mRNA and protein. These data confirm and extend our previous findings on NGF-photoreceptor crosstalk, highlighting that the NGF/αVEGF combination might be an interesting approach for improving neuroprotection of RCS retinal cells and likewise photoreceptors in the presence of neovascularization. Further studies are required to translate this in vitro approach into clinical practice.

CCL5 promotes VEGF-C production and induces lymphangiogenesis by suppressing miR-507 in human chondrosarcoma cells

PubMed Central

Lin, Chih-Yang; Liu, Shih-Chia; Chen, Yen-Ling; Chen, Jih-Jung; Chan, Chia-Han; Lin, Ting-Yi; Chen, Chi-Kuan; Xu, Guo-Hong; Chen, Shiou-Sheng; Tang, Chih-Hsin; Wang, Shih-Wei

2016-01-01

Chondrosarcoma is the second most frequently occurring type of bone malignancy that is characterized by the distant metastasis propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumor lymphangiogenesis and lymphatic metastasis. Chemokine CCL5 has been reported to facilitate angiogenesis and metastasis in chondrosarcoma. However, the effect of chemokine CCL5 on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has largely remained a mystery. In this study, we showed a clinical correlation between CCL5 and VEGF-C as well as tumor stage in human chondrosarcoma tissues. We further demonstrated that CCL5 promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium (CM) from CCL5-overexpressed cells significantly induced tube formation of human lymphatic endothelial cells (LECs). Mechanistic investigations showed that CCL5 activated VEGF-C-dependent lymphangiogenesis by down-regulating miR-507. Moreover, inhibiting CCL5 dramatically reduced VEGF-C and lymphangiogenesis in the chondrosarcoma xenograft animal model. Collectively, we document for the first time that CCL5 induces tumor lymphangiogenesis by the induction of VEGF-C in human cancer cells. Our present study reveals miR-507/VEGF-C signaling as a novel mechanism in CCL5-mediated tumor lymphangiogenesis. Targeting both CCL5 and VEGF-C pathways might serve as the potential therapeutic strategy to block cancer progression and metastasis in chondrosarcoma. PMID:27166194

CCL5 promotes VEGF-C production and induces lymphangiogenesis by suppressing miR-507 in human chondrosarcoma cells.

PubMed

Wang, Li-Hong; Lin, Chih-Yang; Liu, Shih-Chia; Liu, Guan-Ting; Chen, Yen-Ling; Chen, Jih-Jung; Chan, Chia-Han; Lin, Ting-Yi; Chen, Chi-Kuan; Xu, Guo-Hong; Chen, Shiou-Sheng; Tang, Chih-Hsin; Wang, Shih-Wei

2016-06-14

Chondrosarcoma is the second most frequently occurring type of bone malignancy that is characterized by the distant metastasis propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumor lymphangiogenesis and lymphatic metastasis. Chemokine CCL5 has been reported to facilitate angiogenesis and metastasis in chondrosarcoma. However, the effect of chemokine CCL5 on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has largely remained a mystery. In this study, we showed a clinical correlation between CCL5 and VEGF-C as well as tumor stage in human chondrosarcoma tissues. We further demonstrated that CCL5 promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium (CM) from CCL5-overexpressed cells significantly induced tube formation of human lymphatic endothelial cells (LECs). Mechanistic investigations showed that CCL5 activated VEGF-C-dependent lymphangiogenesis by down-regulating miR-507. Moreover, inhibiting CCL5 dramatically reduced VEGF-C and lymphangiogenesis in the chondrosarcoma xenograft animal model. Collectively, we document for the first time that CCL5 induces tumor lymphangiogenesis by the induction of VEGF-C in human cancer cells. Our present study reveals miR-507/VEGF-C signaling as a novel mechanism in CCL5-mediated tumor lymphangiogenesis. Targeting both CCL5 and VEGF-C pathways might serve as the potential therapeutic strategy to block cancer progression and metastasis in chondrosarcoma.

Serum vascular endothelial growth factor B is elevated in women with polycystic ovary syndrome and can be decreased with metformin treatment.

PubMed

Cheng, Feifei; Zhao, Lu; Wu, Yuanyuan; Huang, Tiantian; Yang, Gangyi; Zhang, Zhanyu; Wu, Yijia; Jia, Fang; Wu, Jinlin; Chen, Chen; Liu, Dongfang

2016-03-01

To determine serum vascular endothelial growth factor B (VEGF-B) levels in polycystic ovary syndrome, their association with insulin resistance and β-cell dysfunction, and the effect of metformin on serum VEGF-B levels. A cross-sectional, interventional study. We recruited 103 women with polycystic ovary syndrome and 96 age-matched healthy controls. Serum VEGF-B levels were determined in all participants, and 44 polycystic ovary syndrome patients randomly received metformin. We measured VEGF-B levels in healthy controls and women with polycystic ovary syndrome before and after metformin treatment. Women with polycystic ovary syndrome had higher serum VEGF-B levels, which decreased with metformin treatment. In the lean and overweight/obese groups, patients with polycystic ovary syndrome had higher plasma VEGF-B levels than did healthy controls (P < 0·05). VEGF-B levels were correlated with body mass index, body fat percentage, M values, homeostasis model assessment of insulin resistance and β-cell function indices. A multiple linear regression analysis showed that VEGF-B level was associated with M values after adjusting for age, body mass index, serum sex hormones and serum lipids in women with polycystic ovary syndrome. Serum VEGF-B is significantly higher in women with polycystic ovary syndrome and is closely and positively related to insulin resistance. Metformin treatment reduces VEGF-B levels and ameliorates insulin resistance. © 2015 John Wiley & Sons Ltd.

The role of vascular endothelial growth factor in neurodegeneration and cognitive decline: exploring interactions with biomarkers of Alzheimer disease.

PubMed

Hohman, Timothy J; Bell, Susan P; Jefferson, Angela L

2015-05-01

A subset of older adults present post mortem with Alzheimer disease (AD) pathologic features but without any significant clinical manifestation of dementia. Vascular endothelial growth factor (VEGF) has been implicated in staving off AD-related neurodegeneration. To evaluate whether VEGF levels are associated with brain aging outcomes (hippocampal volume and cognition) and to further evaluate whether VEGF modifies relations between AD biomarkers and brain aging outcomes. Biomarker analysis using neuroimaging and neuropsychological outcomes from the Alzheimer's Disease Neuroimaging Initiative. This prospective longitudinal study across North America included individuals with normal cognition (n = 90), mild cognitive impairment (n = 130), and AD (n = 59) and began in October 2004, with follow-up ongoing. Cerebrospinal fluid VEGF was cross-sectionally related to brain aging outcomes (hippocampal volume, episodic memory, and executive function) using a general linear model and longitudinally using mixed-effects regression. Alzheimer disease biomarker (cerebrospinal fluid β-amyloid 42 and total tau)-by-VEGF interactions evaluated the effect of VEGF on brain aging outcomes in the presence of enhanced AD biomarkers. Vascular endothelial growth factor was associated with baseline hippocampal volume (t277 = 2.62; P = .009), longitudinal hippocampal atrophy (t858 = 2.48; P = .01), and longitudinal decline in memory (t1629 = 4.09; P < .001) and executive function (t1616 = 3.00; P = .003). Vascular endothelial growth factor interacted with tau in predicting longitudinal hippocampal atrophy (t845 = 4.17; P < .001), memory decline (t1610 = 2.49; P = .01), and executive function decline (t1597 = 3.71; P < .001). Vascular endothelial growth factor interacted with β-amyloid 42 in predicting longitudinal memory decline (t1618 = -2.53; P = .01). Elevated cerebrospinal fluid VEGF was associated with more optimal brain aging in vivo. The neuroprotective effect appeared strongest in the presence of enhanced AD biomarkers, suggesting that VEGF may be particularly beneficial in individuals showing early hallmarks of the AD cascade. Future work should evaluate the interaction between VEGF expression in vitro and pathologic burden to address potential mechanisms.

Aging impairs transcriptional regulation of vascular endothelial growth factor in human microvascular endothelial cells: implications for angiogenesis and cell survival.

PubMed

Ahluwalia, A; Jones, M K; Szabo, S; Tarnawski, A S

2014-04-01

In some tissues, aging impairs angiogenesis and reduces expression of vascular endothelial growth factor A (VEGF), a fundamental regulator of angiogenesis. We previously examined angiogenesis in aging and young gastric mucosa in vivo and in vitro and showed that an imbalance between expressions of VEGF (pro-angiogenic factor) and endostatin (anti-angiogenic protein) results in an aging-related impairment of angiogenesis in rats. However, the human relevance of these findings, and whether these mechanisms apply to endothelial cells derived from other tissues, is not clear. Since P-STAT3 and P-CREB are transcription factors that, in association with HIF-1α, can activate VEGF gene expression in some cells (e.g., liver cancer cells, vascular smooth muscle cells), we examined the expression of these two proteins in human dermal microvascular endothelial cells (HMVECs) derived from aging and neonatal individuals. We examined and quantified in vitro angiogenesis, expression of VEGF, P-STAT3, P-CREB and importin-α in HMVECs isolated from neonates (neonatal) and a 66 year old subject (aging). We also examined the effects of treatment with exogenous VEGF and endostatin on in vitro angiogenesis in these cells. Endothelial cells isolated from aging individuals had impaired angiogenesis (vs. neonatal endothelial cells) and reduced expression of VEGF mRNA and protein. Aged HMVECs also had reduced importin-α expression, and reduced expression and nuclear translocation of P-STAT3 and P-CREB. Reduced VEGF gene expression in aged HMVECs strongly correlated with the decreased levels of P-STAT3, P-CREB and importin-α in these cells. Our study clearly demonstrates that endothelial cells from aging individuals have impaired angiogenesis and reduced expression of VEGF likely due to impaired nuclear transport of P-STAT3 and P-CREB transcription factors in these cells.

Regulation of vascular endothelial growth factor-C by tumor necrosis factor-α in the conjunctiva and pterygium.

PubMed

Dong, Yoko; Kase, Satoru; Dong, Zhenyu; Fukuhara, Junichi; Tagawa, Yoshiaki; Ishizuka, Erdal Tan; Murata, Miyuki; Shinmei, Yasuhiro; Ohguchi, Takeshi; Kanda, Atsuhiro; Noda, Kousuke; Ishida, Susumu

2016-08-01

Vascular endothelial growth factor C (VEGF-C) plays an important role in the development of a pterygium through lymphangiogenesis. We examined the association between VEGF-C and tumor necrosis factor-α (TNF-α) in the pathogenesis of pterygia. Cultured conjunctival epithelial cells were treated with TNF-α, and the gene expression levels of VEGFC were evaluated by quantitative polymerase chain reaction (qPCR) and VEGF-C protein expression levels were measured using an enzyme-linked immunosorbent assay (ELISA). In addition, using ELISA, we evaluated the VEGF-C protein expression in the supernatants of cultured conjunctival epithelial cells, in which we neutralized TNF-α using anti‑TNF-α antibody. The gene expression of tumor necrosis factor receptor superfamily, member 1A (TNFRSF1A), known as TNF receptor 1 (TNFR1), was confirmed using reverse transcription PCR in cultured conjunctival epithelial cells. Immunofluorescence microscopy was used to examine the localization of VEGF-C and TNFR1 in pterygium tissues and TNFR1 expression in cultured conjunctival epithelial cells. Immunohistochemistry was used to examine the localization of TNFR1 in pterygia and normal conjunctival tissues. VEGFC gene expression increased in cultured conjunctival epithelial cells 24 h after the addition of TNF-α. The secretion of VEGF-C protein was significantly increased 48 h after the stimulation of cultured conjunctival epithelial cells with TNF-α. Increased VEGF-C protein secretion stimulated by TNF-α was significantly reduced by anti-TNF-α neutralizing antibody treatment. In cultured conjunctival epithelial cells, TNFRSF1A and TNFR1 were expressed. TNFR1 was immunolocalized in normal conjunctival tissues and in human pterygium tissues as well as in VEGF‑C‑positive epithelial cells from human pterygia. Our data demonstrate that TNF-α mediates VEGF-C expression, which plays a critical role in the pathogenesis of pterygia.

Localization and signaling patterns of vascular endothelial growth factors and receptors in human periapical lesions.

PubMed

Virtej, Anca; Løes, Sigbjørn S; Berggreen, Ellen; Bletsa, Athanasia

2013-05-01

Vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key players in vasculogenesis and are also involved in pathologic conditions with bone destruction. Vasculogenesis is critical for disease progression, and bone resorption is a hallmark of apical periodontitis. However, the localization of VEGFs and VEGFRs and their gene signaling pathways in human apical periodontitis have not been thoroughly investigated. The aim of this study was to localize VEGFs and VEGFRs and analyze their gene expression as well as signaling pathways in human periapical lesions. Tissue was collected after endodontic surgery from patients diagnosed with chronic apical periodontitis. Periodontal ligament samples from extracted healthy wisdom teeth was also collected and used as control tissue. In lesion cryosections, VEGFs/VEGFRs were identified by immunohistochemistry/double immunofluorescence by using specific antibodies. A human VEGF signaling polymerase chain reaction array system was used for gene expression analysis comparing lesions with periodontal ligament samples. The histologic evaluation revealed heterogeneous morphology of the periapical lesions with various degrees of inflammatory infiltrates. In the lesions, all investigated factors and receptors were identified in blood vessels and various immune cells. No lymphatic vessels were detected. Gene expression analysis revealed up-regulation of VEGF-A and VEGFR-3, although not significant. Phosphatidylinositol-3-kinases, protein kinase C, mitogen-activated protein kinases, and phospholipases, all known to be involved in VEGF-mediated angiogenic activity, were significantly up-regulated. The cellular and vascular expressions of VEGFs and VEGFRs in chronic apical periodontitis, along with significant alterations of genes mediating VEGF-induced angiogenic responses, suggest ongoing vascular remodeling in established chronic periapical lesions. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Hypoxia preconditioning protection of corneal stromal cells requires HIF1alpha but not VEGF.

PubMed

Xing, Dongmei; Bonanno, Joseph A

2009-05-18

Hypoxia preconditioning protects corneal stromal cells from stress-induced death. This study determined whether the transcription factor HIF-1alpha (Hypoxia Inducible Factor) is responsible and whether this is promulgated by VEGF (Vascular Endothelial Growth Factor). Cultured bovine stromal cells were preconditioned with hypoxia in the presence of cadmium chloride, a chemical inhibitor of HIF-1alpha, and HIF-1alpha siRNA to test if HIF-1alpha activity is needed for hypoxia preconditioning protection from UV-irradiation induced cell death. TUNEL assay was used to detect cell apoptosis after UV-irradiation. RT-PCR and western blot were used to detect the presence of HIF-1alpha and VEGF in transcriptional and translational levels. During hypoxia (0.5% O2), 5 muM cadmium chloride completely inhibited HIF-1alpha expression and reversed the protection by hypoxia preconditioning. HIF-1alpha siRNA (15 nM) reduced HIF-1alpha expression by 90% and produced a complete loss of protection provided by hypoxia preconditioning. Since VEGF is induced by hypoxia, can be HIF-1alpha dependent, and is often protective, we examined the changes in transcription of VEGF and its receptors after 4 h of hypoxia preconditioning. VEGF and its receptors Flt-1 and Flk-1 are up-regulated after hypoxia preconditioning. However, the transcription and translation of VEGF were paradoxically increased by siHIF-1alpha, suggesting that VEGF expression in stromal cells is not down-stream of HIF-1alpha. These findings demonstrate that hypoxia preconditioning protection in corneal stromal cells requires HIF-1alpha, but that VEGF is not a component of the protection.

Minoxidil Induction of VEGF Is Mediated by Inhibition of HIF-Prolyl Hydroxylase

PubMed Central

Yum, Soohwan; Jeong, Seongkeun; Kim, Dohoon; Lee, Sunyoung; Kim, Wooseong; Yoo, Jin-Wook; Kwon, Oh Sang; Kim, Dae-Duk; Min, Do Sik; Jung, Yunjin

2017-01-01

The topical application of minoxidil may achieve millimolar concentrations in the skin. We investigated whether millimolar minoxidil could induce vascular endothelial growth factor (VEGF), a possible effector for minoxidil-mediated hair growth, and how it occurred at the molecular level. Cell-based experiments were performed to investigate a molecular mechanism underlying the millimolar minoxidil induction of VEGF. The inhibitory effect of minoxidil on hypoxia-inducible factor (HIF) prolyl hydroxylase-2 (PHD-2) was tested by an in vitro von Hippel–Lindau protein (VHL) binding assay. To examine the angiogenic potential of millimolar minoxidil, a chorioallantoic membrane (CAM) assay was used. In human keratinocytes and dermal papilla cells, millimolar minoxidil increased the secretion of VEGF, which was not attenuated by a specific adenosine receptor antagonist that inhibits the micromolar minoxidil induction of VEGF. Millimolar minoxidil induced hypoxia-inducible factor-1α (HIF-1α), and the induction of VEGF was dependent on HIF-1. Moreover, minoxidil applied to the dorsal area of mice increased HIF-1α and VEGF in the skin. In an in vitro VHL binding assay, minoxidil directly inhibited PHD-2, thus preventing the hydroxylation of cellular HIF-1α and VHL-dependent proteasome degradation and resulting in the stabilization of HIF-1α protein. Minoxidil inhibition of PHD-2 was reversed by ascorbate, a cofactor of PHD-2, and the minoxidil induction of cellular HIF-1α was abrogated by the cofactor. Millimolar minoxidil promoted angiogenesis in the CAM assay, an in vivo angiogenic test, and this was nullified by the specific inhibition of VEGF. Our data demonstrate that PHD may be the molecular target for millimolar minoxidil-mediated VEGF induction via HIF-1. PMID:29295567

Anti-VEGF/VEGFR therapy for cancer: Reassessing the target

PubMed Central

Sitohy, Basel; Nagy, Janice A.; Dvorak, Harold F.

2012-01-01

Judah Folkman recognized that new blood vessel formation is important for tumor growth and proposed anti-angiogenesis as a novel approach to cancer therapy. Discovery of vascular permeability factor/vascular endothelial growth factor (VEGF-A) as the primary tumor angiogenesis factor prompted the development of a number of drugs that targeted it or its receptors. These agents have often been successful in halting tumor angiogenesis and in regressing rapidly growing mouse tumors. However, results in human cancer have been less impressive. A number of reasons have been offered for the lack of greater success, and we here call attention to the heterogeneity of the tumor vasculature as an important issue. Human and mouse tumors are supplied by at least six well-defined blood vessel types that arise by both angiogenesis and arterio-venogenesis. All six types can be generated in mouse tissues by an adenoviral vector expressing VEGF-A164. Once formed, four of the six types lose their VEGF-A dependency and so their responsiveness to anti-VEGF/VEGFR therapy. If therapies directed against the vasculature are to have a greater impact on human cancer, targets other than VEGF and its receptors will need to be identified on these resistant tumor vessels. PMID:22508695

Extraocular motoneurons of the adult rat show higher levels of vascular endothelial growth factor and its receptor Flk-1 than other cranial motoneurons.

PubMed

Silva-Hucha, Silvia; Hernández, Rosendo G; Benítez-Temiño, Beatriz; Pastor, Ángel M; de la Cruz, Rosa R; Morcuende, Sara

2017-01-01

Recent studies show a relationship between the deficit of vascular endothelial growth factor (VEGF) and motoneuronal degeneration, such as that occurring in amyotrophic lateral sclerosis (ALS). VEGF delivery protects motoneurons from cell death and delayed neurodegeneration in animal models of ALS. Strikingly, extraocular motoneurons show lesser vulnerability to neurodegeneration in ALS compared to other cranial or spinal motoneurons. Therefore, the present study investigates possible differences in VEGF and its main receptor VEGFR-2 or Flk-1 between extraocular and non-extraocular brainstem motoneurons. We performed immunohistochemistry and Western blot to determine the presence of VEGF and Flk-1 in rat motoneurons located in the three extraocular motor nuclei (abducens, trochlear and oculomotor) and to compare it to that observed in two other brainstem nuclei (hypoglossal and facial) that are vulnerable to degeneration. Extraocular motoneurons presented higher amounts of VEGF and its receptor Flk-1 than other brainstem motoneurons, and thus these molecules could be participating in their higher resistance to neurodegeneration. In conclusion, we hypothesize that differences in VEGF availability and signaling could be a contributing factor to the different susceptibility of extraocular motoneurons, when compared with other motoneurons, in neurodegenerative diseases.

Suppression of glioblastoma angiogenicity and tumorigenicity by inhibition of endogenous expression of vascular endothelial growth factor.

PubMed Central

Cheng, S Y; Huang, H J; Nagane, M; Ji, X D; Wang, D; Shih, C C; Arap, W; Huang, C M; Cavenee, W K

1996-01-01

The development of new capillary networks from the normal microvasculature of the host appears to be required for growth of solid tumors. Tumor cells influence this process by producing both inhibitors and positive effectors of angiogenesis. Among the latter, the vascular endothelial growth factor (VEGF) has assumed prime candidacy as a major positive physiological effector. Here, we have directly tested this hypothesis in the brain tumor, glioblastoma multiforme, one of the most highly vascularized human cancers. We introduced an antisense VEGF expression construct into glioblastoma cells and found that (i) VEGF mRNA and protein levels were markedly reduced, (ii) the modified cells did not secrete sufficient factors so as to be chemoattractive for primary human microvascular endothelial cells, (iii) the modified cells were not able to sustain tumor growth in immunodeficient animals, and (iv) the density of in vivo blood vessel formation was reduced in direct relation to the reduction of VEGF secretion and tumor formation. Moreover, revertant cells that recovered the ability to secrete VEGF regained each of these tumorigenic properties. These results suggest that VEGF plays a major angiogenic role in glioblastoma. Images Fig. 1 Fig. 4 PMID:8710899

Effects of nerve growth factor (NGF) on blood vessels area and expression of the angiogenic factors VEGF and TGFbeta1 in the rat ovary

PubMed Central

Julio-Pieper, Marcela; Lara, Hernán E; Bravo, Javier A; Romero, Carmen

2006-01-01

Background Angiogenesis is a crucial process in follicular development and luteogenesis. The nerve growth factor (NGF) promotes angiogenesis in various tissues. An impaired production of this neurotrophin has been associated with delayed wound healing. A variety of ovarian functions are regulated by NGF, but its effects on ovarian angiogenesis remain unknown. The aim of this study was to elucidate if NGF modulates 1) the amount of follicular blood vessels and 2) ovarian expression of two angiogenic factors: vascular endothelial growth factor (VEGF) and transforming growth factor beta 1 (TGFbeta1), in the rat ovary. Results In cultured neonatal rat ovaries, NGF increased VEGF mRNA and protein levels, whereas TGFbeta1 expression did not change. Sectioning of the superior ovarian nerve, which increases ovarian NGF protein content, augmented VEGF immunoreactivity and the area of capillary vessels in ovaries of prepubertal rats compared to control ovaries. Conclusion Results indicate that NGF may be important in the maintenance of the follicular and luteal vasculature in adult rodents, either indirectly, by increasing the expression of VEGF in the ovary, or directly via promoting the proliferation of vascular cells. This data suggests that a disruption on NGF regulation could be a component in ovarian disorders related with impaired angiogenesis. PMID:17096853

Imbalance between vascular endothelial growth factor and endostatin correlates with the prognosis of operable non-small cell lung cancer.

PubMed

Hu, Y; Hu, M-m; Shi, G-L; Han, Y; Li, B-L

2014-09-01

Angiogenesis is regulated by a balance of pro-angiogenic and anti-angiogenic factors. Vascular endothelial growth factor (VEGF) and endostatin respectively represents a frequent component of inducers and inhibitors in the process of angiogenesis. The ratio of VEGF/endostatin may reflect the balance of angiogenic switch. This study aimed to determine whether an imbalance between VEGF/endostatin exists in operable non-small cell lung cancer (NSCLC) patients and to assess the correlation, if any, between the imbalance and the prognosis. Preoperative serum levels of VEGF and endostatin were simultaneously determined by quantitiative enzyme-linked immunosorbent assay (ELISA) and the ratio of them was calculated among 98 NSCLC patients and 51 healthy controls. The relationship between these factors and clinicopathological features, including prognosis, was examined. The ratio of VEGF/endostatin levels was significantly higher in operable NSCLC patients [median, 10.4; interquartile range (IQR), 5.9-19.8] than in normal controls [median, 5.1; IQR, 3.3-9.7] (P = 0.002). While the ratio in patients who were still alive for more than 60 months was 8.3 (IQR, 4.3-17.9), the ratio in those who died was 12.9 (IQR, 8.0-22.1) (p = 0.017). In subgroup analysis of patients with pathological stage N0, there was a statistically significant increase of the survival time in the group with a lower ratio than in the group with a higher ratio (p = 0.032). Multivariate analysis confirmed that the VEGF/endostatin ratio was an independent prognostic factor (p = 0.018). There was an imbalance between VEGF and endostatin in serum of operable NSCLC patients. The imbalance correlated with the prognosis of operable NSCLC. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Molecular characterization of EG-VEGF-mediated angiogenesis: differential effects on microvascular and macrovascular endothelial cells.

PubMed

Brouillet, Sophie; Hoffmann, Pascale; Benharouga, Mohamed; Salomon, Aude; Schaal, Jean-Patrick; Feige, Jean-Jacques; Alfaidy, Nadia

2010-08-15

Endocrine gland derived vascular endothelial growth factor (EG-VEGF) also called prokineticin (PK1), has been identified and linked to several biological processes including angiogenesis. EG-VEGF is abundantly expressed in the highest vascularized organ, the human placenta. Here we characterized its angiogenic effect using different experimental procedures. Immunohistochemistry was used to localize EG-VEGF receptors (PROKR1 and PROKR2) in placental and umbilical cord tissue. Primary microvascular placental endothelial cell (HPEC) and umbilical vein-derived macrovascular EC (HUVEC) were used to assess its effects on proliferation, migration, cell survival, pseudovascular organization, spheroid sprouting, permeability and paracellular transport. siRNA and neutralizing antibody strategies were used to differentiate PROKR1- from PROKR2-mediated effects. Our results show that 1) HPEC and HUVEC express both types of receptors 2) EG-VEGF stimulates HPEC's proliferation, migration and survival, but increases only survival in HUVECs. and 3) EG-VEGF was more potent than VEGF in stimulating HPEC sprout formation, pseudovascular organization, and it significantly increases HPEC permeability and paracellular transport. More importantly, we demonstrated that PROKR1 mediates EG-VEGF angiogenic effects, whereas PROKR2 mediates cellular permeability. Altogether, these data characterized angiogenic processes mediated by EG-VEGF, depicted a new angiogenic factor in the placenta, and suggest a novel view of the regulation of angiogenesis in placental pathologies.

VEGF-Trap: a VEGF blocker with potent antitumor effects.

PubMed

Holash, Jocelyn; Davis, Sam; Papadopoulos, Nick; Croll, Susan D; Ho, Lillian; Russell, Michelle; Boland, Patricia; Leidich, Ray; Hylton, Donna; Burova, Elena; Ioffe, Ella; Huang, Tammy; Radziejewski, Czeslaw; Bailey, Kevin; Fandl, James P; Daly, Tom; Wiegand, Stanley J; Yancopoulos, George D; Rudge, John S

2002-08-20

Vascular endothelial growth factor (VEGF) plays a critical role during normal embryonic angiogenesis and also in the pathological angiogenesis that occurs in a number of diseases, including cancer. Initial attempts to block VEGF by using a humanized monoclonal antibody are beginning to show promise in human cancer patients, underscoring the importance of optimizing VEGF blockade. Previous studies have found that one of the most effective ways to block the VEGF-signaling pathway is to prevent VEGF from binding to its normal receptors by administering decoy-soluble receptors. The highest-affinity VEGF blocker described to date is a soluble decoy receptor created by fusing the first three Ig domains of VEGF receptor 1 to an Ig constant region; however, this fusion protein has very poor in vivo pharmacokinetic properties. By determining the requirements to maintain high affinity while extending in vivo half life, we were able to engineer a very potent high-affinity VEGF blocker that has markedly enhanced pharmacokinetic properties. This VEGF-Trap effectively suppresses tumor growth and vascularization in vivo, resulting in stunted and almost completely avascular tumors. VEGF-Trap-mediated blockade may be superior to that achieved by other agents, such as monoclonal antibodies targeted against the VEGF receptor.

Placenta growth factor not vascular endothelial growth factor A or C can predict the early recurrence after radical resection of hepatocellular carcinoma.

PubMed

Ho, Ming-Chih; Chen, Chiung-Nien; Lee, Hsinyu; Hsieh, Fon-Jou; Shun, Chia-Tung; Chang, Chi-Lun; Lai, Yeun-Tyng; Lee, Po-Huang

2007-06-08

The purpose of this study was to evaluate the relationship between the expression of PlGF in tumor tissue and clinical outcomes in HCC patients. Tumor PlGF and vascular endothelial growth factor (VEGF)-A and VEGF-C mRNA were analyzed. Results demonstrated that patients with PlGF expression levels higher than median tended to have early recurrence compared to patients with PlGF expression lower than median (P=.031). In patients with AJCC stage II-III disease, this difference was even more significant (P=.002). In contrast, VEGF-A and VEGF-C could not predict early recurrence-free survival. Since PlGF expression correlated with early recurrence of HCC, PlGF may be an important prognostic indicator in HCC.

Serum levels of vascular endothelial growth factor in chronic obstructive pulmonary disease.

PubMed

Farid Hosseini, Reza; Jabbari Azad, Farahzad; Yousefzadeh, Hadis; Rafatpanah, Houshang; Hafizi, Saeed; Tehrani, Homan; Khani, Masoud

2014-01-01

Chronic obstructive pulmonary disease (COPD) is a third leading cause of death. In this case control study, we prepared 5 cc bloods from the antecubital vein of 100 COPD patients and 40 healthy individuals as control group. Vascular endothelial growth factor (VEGF) expression protein level was measured by ELISA in both groups. We found that concentration of VEGF in blood serum of patients with COPD (189.9±16pg/ml) was significantly higher than the control group (16.4±3.48pg/ml) (p<0.001). While VEGF serum level in emphysematous patients wasn't significantly different with control group (p=0.07). Furthermore VEGF serum level in COPD patients was proportionally increased with severity of disease (p<0.001). Besides all COPD patients, regardless of their smoking status, were experienced significantly higher levels of VEGF than healthy ones (p=0.001; z=4.3). Our results suggest VEGF serum concentration as the sensitive index for severity and activity of COPD and its prognosis.

Expression of ATF4 and VEGF in chorionic villus tissue in early spontaneous abortion.

PubMed

Chai, Luwei; Ling, Kang; He, Xiaoxi; Yang, Rong

2013-10-01

To explore the relationship between early spontaneous abortion (SA) and the expression of activating transcription factor 4 (ATF4) and vascular endothelial growth factor (VEGF). The expression of ATF4 and VEGF protein and mRNA in villi from first trimester spontaneous abortion (SA, n=30) and normal pregnancy (NP, n=30) were detected by immunohistochemistry and fluorescent quantitative polymerase chain reaction (FQ-PCR). Both protein and mRNA expressions of ATF4 and VEGF in the SA group were significantly lower than in the NP group (P<0.01). Their proteins are expressed mainly in syncytiotrophoblast, cytotrophoblast and villous stromal cells. Correlation analysis showed that the expression of ATF4 was positively correlated with that of VEGF in the SA group (r=0.717, P<0.01). Lower expression of ATF4 and VEGF genes in chorionic villus tissue may participate in the pathogenesis of spontaneous abortion. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Modified rice bran hemicellulose inhibits vascular endothelial growth factor-induced angiogenesis in vitro via VEGFR2 and its downstream signaling pathways

PubMed Central

ZHU, Xia; OKUBO, Aya; IGARI, Naoki; NINOMIYA, Kentaro; EGASHIRA, Yukari

2016-01-01

Angiogenesis is implicated in diverse pathological conditions such as cancer, rheumatoid arthritis, psoriasis, atherosclerosis, and retinal neovascularization. In the present study, we investigated the effects of modified rice bran hemicellulose (MRBH), a water-soluble hemicellulose preparation from rice bran treated with shiitake enzymes, on vascular endothelial growth factor (VEGF)-induced angiogenesis in vitro and its mechanism. We found that MRBH significantly inhibited VEGF-induced tube formation in human umbilical vein endothelial cells (HUVECs) co-cultured with human dermal fibroblasts. We also observed that MRBH dose-dependently suppressed the VEGF-induced proliferation and migration of HUVECs. Furthermore, examination of the anti-angiogenic mechanism indicated that MRBH reduced not only VEGF-induced activation of VEGF receptor 2 but also of the downstream signaling proteins Akt, extracellular signal-regulated protein kinase 1/2, and p38 mitogen-activated protein kinase. These findings suggest that MRBH has in vitro anti-angiogenic effects that are partially mediated through the inhibition of VEGF signaling. PMID:28439487

VEGF-A clinical significance in gastric cancers: immunohistochemical analysis of a wide Italian cohort.

PubMed

Lastraioli, E; Boni, L; Romoli, M R; Crescioli, S; Taddei, A; Beghelli, S; Tomezzoli, A; Vindigni, C; Saragoni, L; Messerini, L; Bernini, M; Bencini, L; Giommoni, E; Freschi, G; Di Costanzo, F; Scarpa, A; Morgagni, P; Farsi, M; Roviello, F; De Manzoni, G; Bechi, P; Arcangeli, A

2014-10-01

The clinical significance of VEGF-A expression in gastric cancer (GC) has been reported with contradicting results. We analyzed the expression and clinical significance of VEGF-A in a wide Italian cohort of GC specimens. VEGF-A expression was tested by immunohistochemistry in 507 patients with GC of all clinical stages. The impact of VEGF-A on overall survival (OS) was evaluated in conjunction with clinical and pathological parameters. In the Italian cohort we studied VEGF-A was not an independent prognostic factor neither at the univariate nor at multivariate analysis. Although frequently expressed, in our study VEGF-A was not able to discriminate between groups of patients with different risk. Copyright © 2014 Elsevier Ltd. All rights reserved.

Targeting VEGF/VEGFRs Pathway in the Antiangiogenic Treatment of Human Cancers by Traditional Chinese Medicine.

PubMed

Zhang, Cheng; Wang, Ning; Tan, Hor-Yue; Guo, Wei; Li, Sha; Feng, Yibin

2018-05-01

Bearing in mind the doctrine of tumor angiogenesis hypothesized by Folkman several decades ago, the fundamental strategy for alleviating numerous cancer indications may be the strengthening application of notable antiangiogenic therapies to inhibit metastasis-related tumor growth. Under physiological conditions, vascular sprouting is a relatively infrequent event unless when specifically stimulated by pathogenic factors that contribute to the accumulation of angiogenic activators such as the vascular endothelial growth factor (VEGF) family and basic fibroblast growth factor (bFGF). Since VEGFs have been identified as the principal cytokine to initiate angiogenesis in tumor growth, synthetic VEGF-targeting medicines containing bevacizumab and sorafenib have been extensively used, but prominent side effects have concomitantly emerged. Traditional Chinese medicines (TCM)-derived agents with distinctive safety profiles have shown their multitarget curative potential by impairing angiogenic stimulatory signaling pathways directly or eliciting synergistically therapeutic effects with anti-angiogenic drugs mainly targeting VEGF-dependent pathways. This review aims to summarize ( a) the up-to-date understanding of the role of VEGF/VEGFR in correlation with proangiogenic mechanisms in various tissues and cells; ( b) the elaboration of antitumor angiogenesis mechanisms of 4 representative TCMs, including Salvia miltiorrhiza, Curcuma longa, ginsenosides, and Scutellaria baicalensis; and ( c) circumstantial clarification of TCM-driven therapeutic actions of suppressing tumor angiogenesis by targeting VEGF/VEGFRs pathway in recent years, based on network pharmacology.

Can anti-vascular endothelial growth factor antibody reverse radiation necrosis? A preclinical investigation.

PubMed

Duan, Chong; Perez-Torres, Carlos J; Yuan, Liya; Engelbach, John A; Beeman, Scott C; Tsien, Christina I; Rich, Keith M; Schmidt, Robert E; Ackerman, Joseph J H; Garbow, Joel R

2017-05-01

Anti-vascular endothelial growth factor (anti-VEGF) antibodies are a promising new treatment for late time-to-onset radiation-induced necrosis (RN). We sought to evaluate and validate the response to anti-VEGF antibody in a mouse model of RN. Mice were irradiated with the Leksell Gamma Knife Perfexion™ and then treated with anti-VEGF antibody, beginning at post-irradiation (PIR) week 8. RN progression was monitored via anatomic and diffusion MRI from weeks 4-12 PIR. Standard histology, using haematoxylin and eosin (H&E), and immunohistochemistry staining were used to validate the response to treatment. After treatment, both post-contrast T1-weighted and T2-weighted image-derived lesion volumes decreased (P < 0.001), while the lesion volumes for the control group increased. The abnormally high apparent diffusion coefficient (ADC) for RN also returned to the ADC range for normal brain following treatment (P < 0.001). However, typical RN pathology was still present histologically. Large areas of focal calcification were observed in ~50% of treated mouse brains. Additionally, VEGF and hypoxia-inducible factor 1-alpha (HIF-1α) were continually upregulated in both the anti-VEGF and control groups. Despite improvements observed radiographically following anti-VEGF treatment, lesions were not completely resolved histologically. The subsequent calcification and the continued upregulation of VEGF and HIF-1α merit further preclinical/clinical investigation.

Can anti-Vascular Endothelial Growth Factor Antibody Reverse Radiation Necrosis? A Preclinical Investigation

PubMed Central

Duan, Chong; Perez-Torres, Carlos J; Yuan, Liya; Engelbach, John A; Beeman, Scott C; Tsien, Christina I; Rich, Keith M; Schmidt, Robert E; Ackerman, Joseph JH; Garbow, Joel R

2017-01-01

Anti-vascular endothelial growth factor (anti-VEGF) antibodies are a promising new treatment for late time-to-onset radiation-induced necrosis (RN). We sought to evaluate and validate the response to anti-VEGF antibody in a mouse model of RN. Mice were irradiated with the Leksell Gamma Knife PerfexionTM and then treated with anti-VEGF antibody, beginning at post-irradiation (PIR) week 8. RN progression was monitored via anatomic and diffusion MRI from weeks 4 to 12 PIR. Standard histology, using haematoxylin and eosin (H&E), and immunohistochemistry staining were used to validate the response to treatment. After treatment, both post-contrast T1-weighted and T2-weighted image-derived lesion volumes decreased (P<0.001), while the lesion volumes for the control group increased. The abnormally high apparent diffusion coefficient (ADC) for RN also returned to the ADC range for normal brain following treatment (P<0.001). However, typical RN pathology was still present histologically. Large areas of focal calcification were observed in ~50% of treated mouse brains. Additionally, VEGF and hypoxia-inducible factor 1-alpha (HIF-1α) were continually upregulated in both the anti-VEGF and control groups. Despite improvements observed radiographically following anti-VEGF treatment, lesions were not completely resolved histologically. The subsequent calcification and the continued upregulation of VEGF and HIF-1α merit further preclinical/clinical investigation. PMID:28425047

[Effects of basic fibroblast growth factor and vascular endothelial growth factor on the proliferation, migration and adhesion of human periodontal ligament stem cells in vitro].

PubMed

Zhang, Rong; Zhang, Mian; Li, Cheng-hua; Wang, Peng-cheng; Chen, Fang; Wang, Qin-tao

2013-05-01

To evaluate the effects of basic fibroblast growth factor (FGF-2) and vascular endothelial growth factor (VEGF) on the proliferation, migration, and adhesion of human periodontal ligament stem cells (PDLSC) in vitro. Human PDLSC were cultured in vitro using tissue culture method.The cells were cultured and incubated with various concentrations of FGF-2 and VEGF [A:α-MEM with 2% fetal bovine serum (FBS) (control 1); B:A supplemented with 20 µg/L FGF-2; C:A supplemented with 10 µg/L VEGF; D:A supplemented with 20 µg/L FGF-2 and 10 µg/L VEGF; E:α-MEM with 10% FBS (control 2); F:E supplemented with 20 µg/L FGF-2; G:E supplemented with 10 µg/L VEGF; H:E supplemented with 20 µg/L FGF-2 and 10 µg/L VEGF]. Soluble tetrazolium salts assay was used to evaluate the proliferative capacity on the 1st, 3rd, 5th and 7th d. Then the groups were changed according to result of the proliferation assay (control:α-MEM with 2% FBS; FGF-2 group:control supplemented with 20 µg/L FGF-2; VEGF:control supplemented with 10 µg/L VEGF; Combination group:control supplemented with 20 µg/L FGF-2 and 10 µg/L VEGF). The cell cycle, migration and adhesion capacities were evaluated using flow cytometer, soluble tetrazolium salts assay, cell adhesion assay and scratch wound-healing motility assay. In 2% volume fraction serum containing medium, FGF-2 and VEGF did not stimulate the cell proliferation. However, in 10% serum condition, in groups treated with FGF-2 for 3,5 or 7 d, the A value was (1.22 ± 0.17, 2.15 ± 0.19, 2.72 ± 0.11) respectively, which were significantly higher than that in the control group (0.76 ± 0.16, 1.25 ± 0.06, 1.64 ± 0.09) (P < 0.01) while lower than that in the group treated with FGF-2 and VEGF in combination on the 5 th and 7 th d (2.46 ± 0.17, 3.18 ± 0.27) ( P < 0.05). The A value in the VEGF group on the 5 th and 7 th d is higher than the control group while lower than the FGF-2 group (1.66 ± 0.05, 2.13 ± 0.13) (P < 0.05). Flow cytometer showed that the proliferation index in VEGF group [(34.3 ± 2.0)% ] were significantly lower than those in FGF-2 [(46.8 ± 3.2)%] group and (FGF-2+ VEGF) group [(45.0 ± 4.0)%] but higher than in the control group [(14.5 ± 1.7)%] (P < 0.01). The cell migration assay indicated that the group stimulated with FGF-2 showed no migration promoted effect. Cell adhesion assay showed that the ratio of the adhesive cells number to the original cells number is greater in the FGF-2 group (79 ± 4) than in the VEGF group (62 ± 4) (P < 0.05). Light microscope identified a better cellular morphology on the adhesive surface in the group with FGF-2 than groups without FGF-2. Both FGF-2 and VEGF could simulate the proliferation of PDLSC in a dose dependent manner, and showed an synergistic effect. FGF-2 was more effective to promote the adhesive capacity of PDLSC compared with VEGF. VEGF could facilitate the migration of PDLSC to the wound side.

VEGF (Vascular Endothelial Growth Factor) and Fibrotic Lung Disease.

PubMed

Barratt, Shaney L; Flower, Victoria A; Pauling, John D; Millar, Ann B

2018-04-24

Interstitial lung disease (ILD) encompasses a group of heterogeneous diseases characterised by varying degrees of aberrant inflammation and fibrosis of the lung parenchyma. This may occur in isolation, such as in idiopathic pulmonary fibrosis (IPF) or as part of a wider disease process affecting multiple organs, such as in systemic sclerosis. Anti-Vascular Endothelial Growth Factor (anti-VEGF) therapy is one component of an existing broad-spectrum therapeutic option in IPF (nintedanib) and may become part of the emerging therapeutic strategy for other ILDs in the future. This article describes our current understanding of VEGF biology in normal lung homeostasis and how changes in its bioavailability may contribute the pathogenesis of ILD. The complexity of VEGF biology is particularly highlighted with an emphasis on the potential non-vascular, non-angiogenic roles for VEGF in the lung, in both health and disease.

Generation of monoclonal antibodies to recombinant vascular endothelial growth factor.

PubMed

Shein, S A; Gurina, O I; Leopol'd, A V; Baklaushev, V P; Korchagina, A A; Grinenko, N F; Ivanova, N V; Volgina, N E; Ryabukhin, I A; Chekhonin, V P

2012-05-01

Female BALB/c mice were subcutaneously immunized with recombinant VEGF-164. After 3 immunization cycles, splenic B cells from immunized mouse were fused with immortalized myeloma culture SP2/0-Ag14 cells. Screening of hybrid cells producing anti-VEGF antibodies was performed by ELISA and immunocytochemical analysis on cultured C6 glioma cells. Subsequent cloning yielded hybridoma stably expressing monoclonal anti-VEGF antibodies recognizing recombinant and native VEGF.

EZH2 promotes tumor progression via regulating VEGF-A/AKT signaling in non-small cell lung cancer.

PubMed

Geng, Jian; Li, Xiao; Zhou, Zhanmei; Wu, Chin-Lee; Dai, Meng; Bai, Xiaoyan

2015-04-10

Enhancer of Zeste Homologue 2 (EZH2) accounts for aggressiveness and unfavorable prognosis of tumor. We investigated the mechanisms and signaling pathways of EZH2 in non-small cell lung carcinoma (NSCLC) progression. Increased expression of EZH2, vascular endothelial growth factor-A (VEGF-A) and AKT phosphorylation correlated with differentiation, lymph node metastasis, size and TNM stage in NSCLC. There was a positive correlation between EZH2 and VEGF-A expression and high EZH2 expression, as an independent prognostic factor, predicted a shorter overall survival time for NSCLC patients. The expression of VEGF-A and phosphorylated Ser(473)-AKT, cell proliferation, migration and metastasis were enhanced in EZH2-overexpressing A549 cells, but inhibited in parental H2087 cells with EZH2 silencing or GSK126 treatment. AKT activity was enhanced by recombinant human VEGF-165 but suppressed by bevacizumab. An AKT inhibitor MK-2206 blocked VEGF-A expression and AKT phosphorylation in parental H2087 and EZH2-overexpressing A549 cells. EZH2 activity was not affected by either VEGF-A stimulation/depletion or MK-2206 inhibition. These results demonstrate that EZH2 promotes lung cancer progression via the VEGF-A/AKT signaling pathway. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Hypoxia-inducible factors promote alveolar development and regeneration.

PubMed

Vadivel, Arul; Alphonse, Rajesh S; Etches, Nicholas; van Haaften, Timothy; Collins, Jennifer J P; O'Reilly, Megan; Eaton, Farah; Thébaud, Bernard

2014-01-01

Understanding how alveoli and the underlying capillary network develop and how these mechanisms are disrupted in disease states is critical for developing effective therapies for lung regeneration. Recent evidence suggests that lung angiogenesis promotes lung development and repair. Vascular endothelial growth factor (VEGF) preserves lung angiogenesis and alveolarization in experimental O2-induced arrested alveolar growth in newborn rats, but combined VEGF+angiopoietin 1 treatment is necessary to correct VEGF-induced vessel leakiness. Hypoxia-inducible factors (HIFs) are transcription factors that activate multiple O2-sensitive genes, including those encoding for angiogenic growth factors, but their role during postnatal lung growth is incompletely understood. By inducing the expression of a range of angiogenic factors in a coordinated fashion, HIF may orchestrate efficient and safe angiogenesis superior to VEGF. We hypothesized that HIF inhibition impairs alveolarization and that HIF activation regenerates irreversible O2-induced arrested alveolar growth. HIF inhibition by intratracheal dominant-negative adenovirus (dnHIF-1α)-mediated gene transfer or chetomin decreased lung HIF-1α, HIF-2α, and VEGF expression and led to air space enlargement and arrested lung vascular growth. In experimental O2-induced arrested alveolar growth in newborn rats, the characteristic features of air space enlargement and loss of lung capillaries were associated with decreased lung HIF-1α and HIF-2α expression. Intratracheal administration of Ad.HIF-1α restored HIF-1α, endothelial nitric oxide synthase, VEGF, VEGFR2, and Tie2 expression and preserved and rescued alveolar growth and lung capillary formation in this model. HIFs promote normal alveolar development and may be useful targets for alveolar regeneration.

High expression of SDF-1 and VEGF is associated with poor prognosis in patients with synovial sarcomas.

PubMed

Feng, Qi; Guo, Peng; Wang, Jin; Zhang, Xiaoyu; Yang, Hui-Chai; Feng, Jian-Gang

2018-03-01

Stromal cell-derived factor-1 (SDF-1) predicts poor clinical outcomes of certain types of cancer. Furthermore, vascular endothelial growth factor (VEGF) promotes the growth and metastasis of solid tumors. The aim of the present study was to examine the expression of SDF-1 and VEGF in patients with synovial sarcoma and to determine their expression is correlated with unfavorable outcomes. Levels of SDF-1 and VEGF proteins were evaluated in 54 patients with synovial sarcoma using immunohistochemical and immunofluorescence staining. Potential associations between the expression of SDF-1 and VEGF and various clinical parameters were analyzed using Pearson's χ 2 test and the Spearman-rho test. Additionally, univariate and multivariate Cox regression analyses were used to identify potential prognostic factors, and the Kaplan-Meier method was used to analyze the overall survival rates of patients. Low SDF-1 and VEGF expression was detected in 20.4% (11/54) and 22.2% (12/54) of patients with synovial sarcoma; moderate expression was detected in 35.2% (19/54) and 37.0% (20/54) of patients and high expression was detected in 44.4% (24 of 54) and 40.7% (22 of 54) of patients, respectively. Levels of SDF-1 and VEGF proteins were significantly associated with histological grade (P<0.05), metastasis (P<0.05) and American Joint Committee on Cancer staging (P<0.05). In addition, levels of SDF-1 and VEGF expression were positively correlated with each other (P<0.001). Univariate analysis also indicated that VEGF expression was associated with shorter overall survival rates in (P<0.05), whereas multivariate analysis demonstrated that SDF-1 expression was associated with shorter patient survival rates (P<0.05). Finally, both SDF-1 and VEGF expression were associated with various characteristics of synovial sarcoma. Therefore, SDF-1 expression may be a potential independent prognostic indicator in patients with synovial sarcomas.

Endothelial Progenitor Cell Mobilization in Preterm Infants With Sepsis Is Associated With Improved Survival.

PubMed

Siavashi, Vahid; Asadian, Simin; Taheri-Asl, Masoud; Keshavarz, Samaneh; Zamani-Ahmadmahmudi, Mohamad; Nassiri, Seyed Mahdi

2017-10-01

Microvascular dysfunction plays a key role in the pathology of sepsis, leading to multi-organ failure, and death. Circulating endothelial progenitor cells (cEPCs) are critically involved in the maintenance of the vascular homeostasis in both physiological and pathological contexts. In this study, concentration of cEPCs in preterm infants with sepsis was determined to recognize whether the EPC mobilization would affect the clinical outcome of infantile sepsis. One hundred and thirty-three preterm infants (81 with sepsis and 52 without sepsis) were enrolled in this study. The release of EPCs in circulation was first quantified. Thereafter, these cells were cultivated and biological features of these cells such as, proliferation and colony forming efficiency were analyzed. The levels of chemoattractant cytokines were also measured in infants. In mouse models of sepsis, effects of VEGF and SDF-1 as well as anti-VEGF and anti-SDF-1 were evaluated in order to shed light upon the role which the EPC mobilization plays in the overall survival of septic animals. Circulating EPCs were significantly higher in preterm infants with sepsis than in the non-sepsis group. Serum levels of VEGF, SDF-1, and Angiopoietin-2 were also higher in preterm infants with sepsis than in control non-sepsis. In the animal experiments, injection of VEGF and SDF-1 prompted the mobilization of EPCs, leading to an improvement in survival whereas injection of anti-VEGF and anti-SDF-1 was associated with significant deterioration of survival. Overall, our results demonstrated the beneficial effects of EPC release in preterm infants with sepsis, with increased mobilization of these cells was associated with improved survival. J. Cell. Biochem. 118: 3299-3307, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Improvement of mesh recolonization in abdominal wall reconstruction with adipose vs. bone marrow mesenchymal stem cells in a rodent model.

PubMed

van Steenberghe, M; Schubert, T; Guiot, Y; Goebbels, R M; Gianello, P

2017-08-01

Reconstruction of muscle defects remains a challenge. Our work assessed the potential of an engineered construct made of a human acellular collagen matrix (HACM) seeded with porcine mesenchymal stem cells (MSCs) to reconstruct abdominal wall muscle defects in a rodent model. This study compared 2 sources of MSCs (bone-marrow, BMSCs, and adipose, ASCs) in vitro and in vivo for parietal defect reconstruction. Cellular viability and growth factor release (VEGF, FGF-Beta, HGF, IGF-1, TGF-Beta) were investigated under normoxic/hypoxic culture conditions. Processed and recellularized HACMs were mechanically assessed. The construct was tested in vivo in full thickness abdominal wall defect treated with HACM alone vs. HACM+ASCs or BMSCs (n=14). Tissue remodeling was studied at day 30 for neo-angiogenesis and muscular reconstruction. A significantly lower secretion of IGF was observed with ASCs vs. BMSCs under hypoxic conditions (-97.6%, p<0.005) whereas significantly higher VEGF/FGF secretions were found with ASCs (+92%, p<0.001 and +72%, p<0.05, respectively). Processing and recellularization did not impair the mechanical properties of the HACM. In vivo, angiogenesis and muscle healing were significantly improved by the HACM+ASCs in comparison to BMSCs (p<0.05) at day 30. A composite graft made of an HACM seeded with ASCs can improve muscle repair by specific growth factor release in hypoxic conditions and by in vivo remodeling (neo-angiogenesis/graft integration) while maintaining mechanical properties. Copyright © 2017 Elsevier Inc. All rights reserved.

The Janus Face of VEGF in Stroke

PubMed Central

Geiseler, Samuel J.; Morland, Cecilie

2018-01-01

The family of vascular endothelial growth factors (VEGFs) are known for their regulation of vascularization. In the brain, VEGFs are important regulators of angiogenesis, neuroprotection and neurogenesis. Dysregulation of VEGFs is involved in a large number of neurodegenerative diseases and acute neurological insults, including stroke. Stroke is the main cause of acquired disabilities, and normally results from an occlusion of a cerebral artery or a hemorrhage, both leading to focal ischemia. Neurons in the ischemic core rapidly undergo necrosis. Cells in the penumbra are exposed to ischemia, but may be rescued if adequate perfusion is restored in time. The neuroprotective and angiogenic effects of VEGFs would theoretically make VEGFs ideal candidates for drug therapy in stroke. However, contradictory to what one might expect, endogenously upregulated levels of VEGF as well as the administration of exogenous VEGF is detrimental in acute stroke. This is probably due to VEGF-mediated blood–brain-barrier breakdown and vascular leakage, leading to edema and increased intracranial pressure as well as neuroinflammation. The key to understanding this Janus face of VEGF function in stroke may lie in the timing; the harmful effect of VEGFs on vessel integrity is transient, as both VEGF preconditioning and increased VEGF after the acute phase has a neuroprotective effect. The present review discusses the multifaceted action of VEGFs in stroke prevention and therapy. PMID:29734653

Intracellular autocrine VEGF signaling promotes EBDC cell proliferation, which can be inhibited by Apatinib.

PubMed

Peng, Sui; Zhang, Yanyan; Peng, Hong; Ke, Zunfu; Xu, Lixia; Su, Tianhong; Tsung, Allan; Tohme, Samer; Huang, Hai; Zhang, Qiuyang; Lencioni, Riccardo; Zeng, Zhirong; Peng, Baogang; Chen, Minhu; Kuang, Ming

2016-04-10

Tumor cells produce vascular endothelial growth factor (VEGF) which can interact with membrane or cytoplasmic VEGF receptors (VEGFRs) to promote cell growth. We aimed to investigate the role of extracellular/intracellular autocrine VEGF signaling and Apatinib, a highly selective VEGFR2 inhibitor, in extrahepatic bile duct cancer (EBDC). We found conditioned medium or recombinant human VEGF treatment promoted EBDC cell proliferation through a phospholipase C-γ1-dependent pathway. This pro-proliferative effect was diminished by VEGF, VEGFR1 or VEGFR2 neutralizing antibodies, but more significantly suppressed by intracellular VEGFR inhibitor. The rhVEGF induced intracellular VEGF signaling by promoting nuclear accumulation of pVEGFR1/2 and enhancing VEGF promoter activity, mRNA and protein expression. Internal VEGFR2 inhibitor Apatinib significantly inhibited intracellular VEGF signaling, suppressed cell proliferation in vitro and delayed xenograft tumor growth in vivo, while anti-VEGF antibody Bevacizumab showed no effect. Clinically, overexpression of pVEGFR1 and pVEGFR2 was significantly correlated with poorer overall survival (P = .007 and P = .020, respectively). In conclusion, the intracellular autocrine VEGF loop plays a predominant role in VEGF-induced cell proliferation. Apatinib is an effective intracellular VEGF pathway blocker that presents a great therapeutic potential in EBDC. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Proangiogenic and Profibrotic Markers in Pulmonary Sarcoidosis.

PubMed

Tuleta, I; Biener, L; Pizarro, C; Nickenig, G; Skowasch, D

2018-04-21

The aim of our study was to determine the blood levels of vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β1, fibroblast growth factor (FGF)-2, and platelet-derived growth factor (PDGF)-AB in different stages of pulmonary sarcoidosis. There were 92 patients in sarcoidosis stages I + II, III, and IV enrolled into the study. All the patients underwent lung diffusing capacity and blood sampling. We found that VEGF levels differed significantly between the stage groups with the peak VEGF concentrations in stage III. TGF-β1 levels were similar in stages I + II and III, and tended to be lower in stage IV. The analysis of the subgroups showed increased VEGF and FGF-2, and reduced TGF-β1 concentration in stages I + II patients with relevantly reduced lung diffusing capacity or increased sarcoidosis activity compared to patients with normal lung diffusing capacity or inactive sarcoidosis. A tendency towards increased VEGF, PDGF-AB and TGF-β1 levels was observed in the analogical subgroup analysis within the stage III. We conclude that proangiogenic VEGF, and profibrotic FGF-2 and PDGF-AB may contribute to the progression of sarcoidosis, whereas TGF-β1, with its dual anti-inflammatory and profibrotic actions, may play a dichotomous protective or deleterious role. Reduced diffusing capacity and active sarcoidosis are associated with an unfavorable constellation of the markers studied, which predicts a progressive disease course.

Role of vascular endothelial cell growth factor in Ovarian Hyperstimulation Syndrome.

PubMed Central

Levin, E R; Rosen, G F; Cassidenti, D L; Yee, B; Meldrum, D; Wisot, A; Pedram, A

1998-01-01

Controlled ovarian hyperstimulation with gonadotropins is followed by Ovarian Hyperstimulation Syndrome (OHSS) in some women. An unidentified capillary permeability factor from the ovary has been implicated, and vascular endothelial cell growth/permeability factor (VEGF) is a candidate protein. Follicular fluids (FF) from 80 women who received hormonal induction for infertility were studied. FFs were grouped according to oocyte production, from group I (0-7 oocytes) through group IV (23-31 oocytes). Group IV was comprised of four women with the most severe symptoms of OHSS. Endothelial cell (EC) permeability induced by the individual FF was highly correlated to oocytes produced (r2 = 0.73, P < 0.001). Group IV FF stimulated a 63+/-4% greater permeability than FF from group I patients (P < 0. 01), reversed 98% by anti-VEGF antibody. Group IV fluids contained the VEGF165 isoform and significantly greater concentrations of VEGF as compared with group I (1,105+/-87 pg/ml vs. 353+/-28 pg/ml, P < 0. 05). Significant cytoskeletal rearrangement of F-actin into stress fibers and a destruction of ZO-1 tight junction protein alignment was caused by group IV FF, mediated in part by nitric oxide. These mechanisms, which lead to increased EC permeability, were reversed by the VEGF antibody. Our results indicate that VEGF is the FF factor responsible for increased vascular permeability, thereby contributing to the pathogenesis of OHSS. PMID:9835623

Association of vascular endothelial growth factor (VEGF) gene polymorphism and increased serum VEGF concentration with pancreatic adenocarcinoma.

PubMed

Sivaprasad, Siddapuram; Govardhan, Bale; Harithakrishna, Ramanujam; Venkat Rao, Guduru; Pradeep, Rebala; Kunal, Bharadhwaj; Ramakrishna, Nalla; Anuradha, Shekaran; Reddy, Duvvuru Nageshwar

2013-01-01

BACKGROUND &AIM: Pancreatic cancer is related to high mortality rate. The vascular endothelial growth factor (VEGF) has a strong influence in tumor-related angiogenesis having association with the grade of angiogenesis and the prognosis of different solid tumors including pancreatic cancer. The present study was aimed to analyze the genotype and haplotype distribution of VEGF gene single nucleotide polymorphisms (SNPs), -460T/C, +405G/C, +936C/T, in patients with pancreatic adenocarcinoma from South India, and the effect of these SNPs on serum VEGF level. Total 80 patients with pancreatic adenocarcinoma and 87 controls were recruited. The genotype of VEGF gene polymorphisms was determined in both patients and controls using polymerase chain reaction-restriction fragment length polymorphism method. The serum VEGF protein was estimated by standard enzyme-linked immunosorbent assay. The genotype, +405G/G of VEGF gene showed a significant association with the patients with pancreatic adenocarcinoma (P = 0.012, Odds ratio: 2.133), whereas no significant difference was found in the genotype distribution of SNPs, -460C/T and +936C/T between patient and control groups (P > 0.05). Serum VEGF level was found to be significantly high in patients (1315.10 pg/Ml, SD ± 230.79) when compared to controls (591.35 pg/mL, SD ± 92.48) (P < 0.0001), which showed a strong genotype-phenotype correlation between genotype +405G/G and serum VEGF level. Further, the haplotype C-G-T showed a strong association with the disease, and no specific haplotype was associated with increased serum VEGF level. The polymorphism, +405G/C but not -460T/C and +936C/T, of VEGF gene is strongly associated with pancreatic adenocarcinoma, and this SNP has significant influence on serum VEGF level. Copyright © 2013 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Intramyocardial VEGF-B167 gene delivery delays the progression towards congestive failure in dogs with pacing-induced dilated cardiomyopathy.

PubMed

Pepe, Martino; Mamdani, Mohammed; Zentilin, Lorena; Csiszar, Anna; Qanud, Khaled; Zacchigna, Serena; Ungvari, Zoltan; Puligadda, Uday; Moimas, Silvia; Xu, Xiaobin; Edwards, John G; Hintze, Thomas H; Giacca, Mauro; Recchia, Fabio A

2010-06-25

Vascular endothelial growth factor (VEGF)-B selectively binds VEGF receptor (VEGFR)-1, a receptor that does not mediate angiogenesis, and is emerging as a major cytoprotective factor. To test the hypothesis that VEGF-B exerts non-angiogenesis-related cardioprotective effects in nonischemic dilated cardiomyopathy. AAV-9-carried VEGF-B(167) cDNA (10(12) genome copies) was injected into the myocardium of chronically instrumented dogs developing tachypacing-induced dilated cardiomyopathy. After 4 weeks of pacing, green fluorescent protein-transduced dogs (AAV-control, n=8) were in overt congestive heart failure, whereas the VEGF-B-transduced (AAV-VEGF-B, n=8) were still in a well-compensated state, with physiological arterial Po(2). Left ventricular (LV) end-diastolic pressure in AAV-VEGF-B and AAV-control was, respectively, 15.0+/-1.5 versus 26.7+/-1.8 mm Hg and LV regional fractional shortening was 9.4+/-1.6% versus 3.0+/-0.6% (all P<0.05). VEGF-B prevented LV wall thinning but did not induce cardiac hypertrophy and did not affect the density of alpha-smooth muscle actin-positive microvessels, whereas it normalized TUNEL-positive cardiomyocytes and caspase-9 and -3 activation. Consistently, activated Akt, a major negative regulator of apoptosis, was superphysiological in AAV-VEGF-B, whereas the proapoptotic intracellular mediators glycogen synthase kinase (GSK)-3beta and FoxO3a (Akt targets) were activated in AAV-control, but not in AAV-VEGF-B. Cardiac VEGFR-1 expression was reduced 4-fold in all paced dogs, suggesting that exogenous VEGF-B(167) exerted a compensatory receptor stimulation. The cytoprotective effects of VEGF-B(167) were further elucidated in cultured rat neonatal cardiomyocytes exposed to 10(-8) mol/L angiotensin II: VEGF-B(167) prevented oxidative stress, loss of mitochondrial membrane potential, and, consequently, apoptosis. We determined a novel, angiogenesis-unrelated cardioprotective effect of VEGF-B(167) in nonischemic dilated cardiomyopathy, which limits apoptotic cell loss and delays the progression toward failure.

Continuous delivery of rhBMP2 and rhVEGF165 at a certain ratio enhances bone formation in mandibular defects over the delivery of rhBMP2 alone--An experimental study in rats.

PubMed

Lohse, N; Moser, N; Backhaus, S; Annen, T; Epple, M; Schliephake, H

2015-12-28

The aim of the present study was to test the hypothesis that different amounts of vascular endothelial growth factor and bone morphogenic protein differentially affect bone formation when applied for repair of non-healing defects in the rat mandible. Porous composite PDLLA/CaCO3 carriers were fabricated as slow release carriers and loaded with rhBMP2 and rhVEGF165 in 10 different dosage combinations using gas foaming with supercritical carbon dioxide. They were implanted in non-healing defects of the mandibles of 132 adult Wistar rats with additional lateral augmentation. Bone formation was assessed both radiographically (bone volume) and by histomorphometry (bone density). The use of carriers with a ratio of delivery of VEGF/BMP between 0.7 and 1.2 was significantly related to the occurrence of significant increases in radiographic bone volume and/or histologic bone density compared to the use of carriers with a ratio of delivery of ≤ 0.5 when all intervals and all outcome parameters were considered. Moreover, simultaneous delivery at this ratio helped to "save" rhBMP2 as both bone volume and bone density after 13 weeks were reached/surpassed using half the dosage required for rhBMP2 alone. It is concluded, that the combined delivery of rhVEGF165 and rhBMP2 for repair of critical size mandibular defects can significantly enhance volume and density of bone formation over delivery of rhBMP2 alone. It appears from the present results that continuous simultaneous delivery of rhVEGF165 and rhBMP2 at a ratio of approximately 1 is favourable for the enhancement of bone formation. Copyright © 2015. Published by Elsevier B.V.

Release kinetics of platelet-derived and plasma-derived growth factors from autologous plasma rich in growth factors.

PubMed

Anitua, Eduardo; Zalduendo, Mari Mar; Alkhraisat, Mohammad Hamdan; Orive, Gorka

2013-10-01

Many studies have evaluated the biological effects of platelet rich plasma reporting the final outcomes on cell and tissues. However, few studies have dealt with the kinetics of growth factor delivery by plasma rich in growth factors. Venous blood was obtained from three healthy volunteers and processed with PRGF-Endoret technology to prepare autologous plasma rich in growth factors. The gel-like fibrin scaffolds were then incubated in triplicate, in a cell culture medium to monitor the release of PDGF-AB, VEGF, HGF and IGF-I during 8 days of incubation. A leukocyte-platelet rich plasma was prepared employing the same technology and the concentrations of growth factors and interleukin-1β were determined after 24h of incubation. After each period, the medium was collected, fibrin clot was destroyed and the supernatants were stored at -80°C until analysis. The growth factor delivery is diffusion controlled with a rapid initial release by 30% of the bioactive content after 1h of incubation and a steady state release when almost 70% of the growth factor content has been delivered. Autologous fibrin matrix retained almost 30% of the amount of the growth factors after 8 days of incubation. The addition of leukocytes to the formula of platelet rich plasma did not increase the concentration of the growth factors, while it drastically increased the presence of pro-inflammatory IL-1β. Further studies employing an in vitro inflammatory model would be interesting to study the difference in growth factors and pro-inflammatory cytokines between leukocyte-free and leukocyte-rich platelet rich plasma. Copyright © 2013 Elsevier GmbH. All rights reserved.

Vascular endothelial growth factor-D is a key molecule that enhances lymphatic metastasis of soft tissue sarcomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yanagawa, Takashi, E-mail: tyanagaw@med.gunma-u.ac.jp; Shinozaki, Tetsuya; Watanabe, Hideomi

2012-04-15

Studies on lymph node metastasis of soft tissue sarcomas are insufficient because of its rarity. In this study, we examined the expressions of vascular endothelial growth factor (VEGF)-C and VEGF-D in soft tissue sarcomas metastasized to lymph nodes. In addition, the effects of the two molecules on the barrier function of a lymphatic endothelial cell monolayer against sarcoma cells were analyzed. We examined 7 patients who had soft tissue sarcomas with lymph node metastases and who had undergone neither chemotherapy nor radiotherapy before lymphadenectomy. Immunohistochemistry revealed that 2 of 7 sarcomas that metastasized to lymph nodes expressed VEGF-C both inmore » primary and metastatic lesions. On the other hand, VEGF-D expression was detected in 4 of 7 primary and 7 of 7 metastatic lesions, respectively. Interestingly, 3 cases that showed no VEGF-D expression at primary sites expressed VEGF-D in metastatic lesions. Recombinant VEGF-C at 10{sup -8} and VEGF-D at 10{sup -7}and 10{sup -8} g/ml significantly increased the random motility of lymphatic endothelial cells compared with controls. VEGF-D significantly increased the migration of sarcoma cells through lymphatic endothelial monolayers. The fact that VEGF-D induced the migration of fibrosarcomas through the lymphatic endothelial monolayer is the probable reason for the strong relationship between VEGF-D expression and lymph node metastasis in soft tissue sarcomas. The important propensities of this molecule for the increase of lymph node metastases are not only lymphangiogenesis but also down-regulation of the barrier function of lymphatic endothelial monolayers, which facilitates sarcoma cells entering the lymphatic circulation.« less

Elevated Levels of Serum Vascular Endothelial Growth Factor-A Are Not Related to NK Cell Parameters in Recurrent IVF Failure.

PubMed

Bansal, Rhea; Ford, Brian; Bhaskaran, Shree; Thum, Meenyau; Bansal, Amolak

2017-01-01

Vascular Endothelial Growth Factor and NK cells have an interrelated role in angiogenesis that is critical for placentation and success of in vitro fertilization. An attempt was made to assess a possible relationship between the two in this study. A case control study was performed comparing the serum levels of VEGF-A and its receptor VEGF-R1 with levels of NK cells, activated NK cells and NK cytotoxicity in 62 women with Repeated Implantation Failure (RIF). The healthy control group consisted of 72 women of similar age, without known issues in achieving pregnancy or evidence of autoimmunity. Levels of VEGF-A and VEGF-R1 were quantified by ELISA methods with standard curve interpolation. NK cell subsets were determined with flow cytometry using fluorescent-tagged anti-CD56, anti-CD16, anti-CD3 and anti-CD69. NK cytotoxicity was performed by incubating peripheral blood mononuclear cells and K562 cultured cells with propidium iodide, steroid, intralipid and intravenous immunoglobulin, using previously described methods. Statistical analysis involved Mann-Whitney-U and Spearman's rank correlation testing with p-values defined as <0.05. It was found that VEGF-A levels were significantly raised in women with RIF compared to healthy controls (362.9 vs . 171.6 pg/ml , p<0.0001), with no difference in VEGF-R1 levels between groups (1499 vs . 1202 pg/ml , p=0.4082). There was no correlation between VEGF-A or VEGF-R1 and the absolute levels of circulating NK cells, CD69 activated NK cells or NK cytotoxicity. The absence of correlation between VEGF-A or VEGF-R1 and NK cells suggests VEGF secretion and regulation is independent of NK cell activity in RIF.

Co-Expression of α9β1 Integrin and VEGF-D Confers Lymphatic Metastatic Ability to a Human Breast Cancer Cell Line MDA-MB-468LN

PubMed Central

Majumder, Mousumi; Rodriguez-Torres, Mauricio; Torres-Garcia, Jose; Wiebe, Ryan; Timoshenko, Alexander V.; Bhattacharjee, Rabindra N.; Chambers, Ann F.; Lala, Peeyush K.

2012-01-01

Introduction and Objectives Lymphatic metastasis is a common occurrence in human breast cancer, mechanisms remaining poorly understood. MDA-MB-468LN (468LN), a variant of the MDA-MB-468GFP (468GFP) human breast cancer cell line, produces extensive lymphatic metastasis in nude mice. 468LN cells differentially express α9β1 integrin, a receptor for lymphangiogenic factors VEGF-C/-D. We explored whether (1) differential production of VEGF-C/-D by 468LN cells provides an autocrine stimulus for cellular motility by interacting with α9β1 and a paracrine stimulus for lymphangiogenesis in vitro as measured with capillary-like tube formation by human lymphatic endothelial cells (HMVEC-dLy); (2) differential expression of α9 also promotes cellular motility/invasiveness by interacting with macrophage derived factors; (3) stable knock-down of VEGF-D or α9 in 468LN cells abrogates lymphangiogenesis and lymphatic metastasis in vivo in nude mice. Results A comparison of expression of cyclo-oxygenase (COX)-2 (a VEGF-C/-D inducer), VEGF-C/-D and their receptors revealed little COX-2 expression by either cells. However, 468LN cells showed differential VEGF-D and α9β1 expression, VEGF-D secretion, proliferative, migratory/invasive capacities, latter functions being stimulated further with VEGF-D. The requirement of α9β1 for native and VEGF-D-stimulated proliferation, migration and Erk activation was demonstrated by treating with α9β1 blocking antibody or knock-down of α9. An autocrine role of VEGF-D in migration was shown by its impairment by silencing VEGF-D and restoration with VEGF-D. 468LN cells and their soluble products stimulated tube formation, migration/invasiveness of HMVEC-dLy cell in a VEGF-D dependent manner as indicated by the loss of stimulation by silencing VEGF-D in 468LN cells. Furthermore, 468LN cells showed α9-dependent stimulation of migration/invasiveness by macrophage products. Finally, capacity for intra-tumoral lymphangiogenesis and lymphatic metastasis in nude mice was completely abrogated by stable knock-down of either VEGF-D or α9 in 468LN cells. Conclusion Differential capacity for VEGF-D production and α9β1 integrin expression by 468LN cells jointly contributed to their lymphatic metastatic phenotype. PMID:22545097

Regulation of alternative VEGF-A mRNA splicing is a therapeutic target for analgesia.

PubMed

Hulse, R P; Beazley-Long, N; Hua, J; Kennedy, H; Prager, J; Bevan, H; Qiu, Y; Fernandes, E S; Gammons, M V; Ballmer-Hofer, K; Gittenberger de Groot, A C; Churchill, A J; Harper, S J; Brain, S D; Bates, D O; Donaldson, L F

2014-11-01

Vascular endothelial growth factor-A (VEGF-A) is best known as a key regulator of the formation of new blood vessels. Neutralization of VEGF-A with anti-VEGF therapy e.g. bevacizumab, can be painful, and this is hypothesized to result from a loss of VEGF-A-mediated neuroprotection. The multiple vegf-a gene products consist of two alternatively spliced families, typified by VEGF-A165a and VEGF-A165b (both contain 165 amino acids), both of which are neuroprotective. Under pathological conditions, such as in inflammation and cancer, the pro-angiogenic VEGF-A165a is upregulated and predominates over the VEGF-A165b isoform. We show here that in rats and mice VEGF-A165a and VEGF-A165b have opposing effects on pain, and that blocking the proximal splicing event - leading to the preferential expression of VEGF-A165b over VEGF165a - prevents pain in vivo. VEGF-A165a sensitizes peripheral nociceptive neurons through actions on VEGFR2 and a TRPV1-dependent mechanism, thus enhancing nociceptive signaling. VEGF-A165b blocks the effect of VEGF-A165a. After nerve injury, the endogenous balance of VEGF-A isoforms switches to greater expression of VEGF-Axxxa compared to VEGF-Axxxb, through an SRPK1-dependent pre-mRNA splicing mechanism. Pharmacological inhibition of SRPK1 after traumatic nerve injury selectively reduced VEGF-Axxxa expression and reversed associated neuropathic pain. Exogenous VEGF-A165b also ameliorated neuropathic pain. We conclude that the relative levels of alternatively spliced VEGF-A isoforms are critical for pain modulation under both normal conditions and in sensory neuropathy. Altering VEGF-Axxxa/VEGF-Axxxb balance by targeting alternative RNA splicing may be a new analgesic strategy. Copyright © 2014. Published by Elsevier Inc.

Aberrant, ectopic expression of VEGF and VEGF receptors 1 and 2 in malignant colonic epithelial cells. Implications for these cells growth via an autocrine mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahluwalia, Amrita; Jones, Michael K.; Department of Medicine, University of California, Irvine, CA

2013-08-09

Highlights: •Malignant colonic epithelial cells express VEGF and its receptors. •Cultured colon cancer cells secrete VEGF into the medium. •Inhibition of VEGF receptor significantly decreases colon cancer cell proliferation. •VEGF is critical for colon cancer cell growth. -- Abstract: Vascular endothelial growth factor A (referred to as VEGF) is implicated in colon cancer growth. Currently, the main accepted mechanism by which VEGF promotes colon cancer growth is via the stimulation of angiogenesis, which was originally postulated by late Judah Folkman. However, the cellular source of VEGF in colon cancer tissue; and, the expression of VEGF and its receptors VEGF-R1 andmore » VEGF-R2 in colon cancer cells are not fully known and are subjects of controversy. Material and methods: We examined and quantified expression of VEGF, VEGF-R1 and VEGF-R2 in three different human colonic tissue arrays containing sections of adenocarcinoma (n = 43) and normal mucosa (n = 41). In human colon cancer cell lines HCT116 and HT29 and normal colon cell lines NCM356 and NCM460, we examined expression of VEGF, VEGF-R1 and VEGF-R2 mRNA and protein, VEGF production and secretion into the culture medium; and, the effect of a potent, selective inhibitor of VEGF receptors, AL-993, on cell proliferation. Results: Human colorectal cancer specimens had strong expression of VEGF in cancer cells and also expressed VEGF-R1 and VEGF-R2.In vitro studies showed that human colon cancer cell lines, HCT116 and HT29, but not normal colonic cell lines, express VEGF, VEGF-R1 and VEGF-R2 and secrete VEGF into the medium up to a concentration 2000 pg/ml within 48 h. Furthermore, we showed that inhibition of VEGF receptors using a specific VEGF-R inhibitor significantly reduced proliferation (by >50%) of cultured colon cancer cell lines. Conclusions: Our findings support the contention that VEGF generated by colon cancer cells stimulates their growth directly through an autocrine mechanism that is independent of its primary function in the induction of angiogenesis.« less

Amphiregulin enhances VEGF-A production in human chondrosarcoma cells and promotes angiogenesis by inhibiting miR-206 via FAK/c-Src/PKCδ pathway.

PubMed

Wang, Chao-Qun; Huang, Yu-Wen; Wang, Shih-Wei; Huang, Yuan-Li; Tsai, Chun-Hao; Zhao, Yong-Ming; Huang, Bi-Fei; Xu, Guo-Hong; Fong, Yi-Chin; Tang, Chih-Hsin

2017-01-28

Chondrosarcoma is the second most common primary malignancy of bone after myeloma and osteosarcoma. Chondrosarcoma development may be linked to angiogenesis, which is principally elicited by vascular endothelial growth factor-A (VEGF-A). The expression of VEGF-A has been recognized as a prognostic marker in angiogenesis. Amphiregulin (AR), an epidermal growth factor receptor ligand, promotes tumor proliferation, metastasis and angiogenesis. However, the role of AR in VEGF-A expression and angiogenesis in human chondrosarcoma remains largely unknown. This current study shows that AR promoted VEGF-A production and induced angiogenesis of human endothelial progenitor cells. Moreover, AR-enhanced VEGF-A expression and angiogenesis involved the FAK, c-Src and PKCδ signaling pathways, while miR-206 expression was negatively mediated by AR via the FAK, c-Src and PKCδ pathways. Our results illustrate the clinical significance between AR, VEGF-A and miR-206, as well as tumor stage, in human chondrosarcoma. AR may represent a novel therapeutic target in the metastasis and angiogenesis of chondrosarcoma. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Anti-VEGF/VEGFR therapy for cancer: reassessing the target.

PubMed

Sitohy, Basel; Nagy, Janice A; Dvorak, Harold F

2012-04-15

Judah Folkman recognized that new blood vessel formation is important for tumor growth and proposed antiangiogenesis as a novel approach to cancer therapy. Discovery of vascular permeability factor VEGF-A as the primary tumor angiogenesis factor prompted the development of a number of drugs that targeted it or its receptors. These agents have often been successful in halting tumor angiogenesis and in regressing rapidly growing mouse tumors. However, results in human cancer have been less impressive. A number of reasons have been offered for the lack of greater success, and, here, we call attention to the heterogeneity of the tumor vasculature as an important issue. Human and mouse tumors are supplied by at least 6 well-defined blood vessel types that arise by both angiogenesis and arterio-venogenesis. All 6 types can be generated in mouse tissues by an adenoviral vector expressing VEGF-A(164). Once formed, 4 of the 6 types lose their VEGF-A dependency, and so their responsiveness to anti-VEGF/VEGF receptor therapy. If therapies directed against the vasculature are to have a greater impact on human cancer, targets other than VEGF and its receptors will need to be identified on these resistant tumor vessels.

Plasma Vascular Endothelial Growth Factor Concentrations after Intravitreous Anti-Vascular Endothelial Growth Factor Therapy for Diabetic Macular Edema.

PubMed

Jampol, Lee M; Glassman, Adam R; Liu, Danni; Aiello, Lloyd Paul; Bressler, Neil M; Duh, Elia J; Quaggin, Susan; Wells, John A; Wykoff, Charles C

2018-07-01

To assess systemic vascular endothelial growth factor (VEGF)-A levels after treatment with intravitreous aflibercept, bevacizumab, or ranibizumab. Comparative-effectiveness trial with participants randomly assigned to 2 mg aflibercept, 1.25 mg bevacizumab, or 0.3 mg ranibizumab after a re-treatment algorithm. Participants with available plasma samples (N = 436). Plasma samples were collected before injections at baseline and 4-week, 52-week, and 104-week visits. In a preplanned secondary analysis, systemic-free VEGF levels from an enzyme-linked immunosorbent assay were compared across anti-VEGF agents and correlated with systemic side effects. Changes in the natural log (ln) of plasma VEGF levels. Baseline free VEGF levels were similar across all 3 groups. At 4 weeks, mean ln(VEGF) changes were -0.30±0.61 pg/ml, -0.31±0.54 pg/ml, and -0.02±0.44 pg/ml for the aflibercept, bevacizumab, and ranibizumab groups, respectively. The adjusted differences between treatment groups (adjusted confidence interval [CI]; P value) were -0.01 (-0.12 to +0.10; P = 0.89), -0.31 (-0.44 to -0.18; P < 0.001), and -0.30 (-0.43 to -0.18; P < 0.001) for aflibercept-bevacizumab, aflibercept-ranibizumab, and bevacizumab-ranibizumab, respectively. At 52 weeks, a difference in mean VEGF changes between bevacizumab and ranibizumab persisted (-0.23 [-0.38 to -0.09]; P < 0.001); the difference between aflibercept and ranibizumab was -0.12 (P = 0.07) and between aflibercept and bevacizumab was +0.11 (P = 0.07). Treatment group differences at 2 years were similar to 1 year. No apparent treatment differences were detected at 52 or 104 weeks in the cohort of participants not receiving injections within 1 or 2 months before plasma collection. Participants with (N = 9) and without (N = 251) a heart attack or stroke had VEGF levels that appeared similar. These data suggest that decreases in plasma free-VEGF levels are greater after treatment with aflibercept or bevacizumab compared with ranibizumab at 4 weeks. At 52 and 104 weeks, a greater decrease was observed in bevacizumab versus ranibizumab. Results from 2 subgroups of participants who did not receive injections within at least 1 month and 2 months before collection suggest similar changes in VEGF levels after stopping injections. It is unknown whether VEGF levels return to normal as the drug is cleared from the system or whether the presence of the drug affects the assay's ability to accurately measure free VEGF. No significant associations between VEGF concentration and systemic factors were noted. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

VEGF-ablation therapy reduces drug delivery and therapeutic response in ECM-dense tumors.

PubMed

Röhrig, F; Vorlová, S; Hoffmann, H; Wartenberg, M; Escorcia, F E; Keller, S; Tenspolde, M; Weigand, I; Gätzner, S; Manova, K; Penack, O; Scheinberg, D A; Rosenwald, A; Ergün, S; Granot, Z; Henke, E

2017-01-05

The inadequate transport of drugs into the tumor tissue caused by its abnormal vasculature is a major obstacle to the treatment of cancer. Anti-vascular endothelial growth factor (anti-VEGF) drugs can cause phenotypic alteration and maturation of the tumor's vasculature. However, whether this consistently improves delivery and subsequent response to therapy is still controversial. Clinical results indicate that not all patients benefit from antiangiogenic treatment, necessitating the development of criteria to predict the effect of these agents in individual tumors. We demonstrate that, in anti-VEGF-refractory murine tumors, vascular changes after VEGF ablation result in reduced delivery leading to therapeutic failure. In these tumors, the impaired response after anti-VEGF treatment is directly linked to strong deposition of fibrillar extracellular matrix (ECM) components and high expression of lysyl oxidases. The resulting condensed, highly crosslinked ECM impeded drug permeation, protecting tumor cells from exposure to small-molecule drugs. The reduced vascular density after anti-VEGF treatment further decreased delivery in these tumors, an effect not compensated by the improved vessel quality. Pharmacological inhibition of lysyl oxidases improved drug delivery in various tumor models and reversed the negative effect of VEGF ablation on drug delivery and therapeutic response in anti-VEGF-resistant tumors. In conclusion, the vascular changes after anti-VEGF therapy can have a context-dependent negative impact on overall therapeutic efficacy. A determining factor is the tumor ECM, which strongly influences the effect of anti-VEGF therapy. Our results reveal the prospect to revert a possible negative effect and to potentiate responsiveness to antiangiogenic therapy by concomitantly targeting ECM-modifying enzymes.

VEGF-ablation therapy reduces drug delivery and therapeutic response in ECM-dense tumors

PubMed Central

Röhrig, F; Vorlová, S; Hoffmann, H; Wartenberg, M; Escorcia, F E; Keller, S; Tenspolde, M; Weigand, I; Gätzner, S; Manova, K; Penack, O; Scheinberg, D A; Rosenwald, A; Ergün, S; Granot, Z; Henke, E

2017-01-01

The inadequate transport of drugs into the tumor tissue caused by its abnormal vasculature is a major obstacle to the treatment of cancer. Anti-vascular endothelial growth factor (anti-VEGF) drugs can cause phenotypic alteration and maturation of the tumor's vasculature. However, whether this consistently improves delivery and subsequent response to therapy is still controversial. Clinical results indicate that not all patients benefit from antiangiogenic treatment, necessitating the development of criteria to predict the effect of these agents in individual tumors. We demonstrate that, in anti-VEGF-refractory murine tumors, vascular changes after VEGF ablation result in reduced delivery leading to therapeutic failure. In these tumors, the impaired response after anti-VEGF treatment is directly linked to strong deposition of fibrillar extracellular matrix (ECM) components and high expression of lysyl oxidases. The resulting condensed, highly crosslinked ECM impeded drug permeation, protecting tumor cells from exposure to small-molecule drugs. The reduced vascular density after anti-VEGF treatment further decreased delivery in these tumors, an effect not compensated by the improved vessel quality. Pharmacological inhibition of lysyl oxidases improved drug delivery in various tumor models and reversed the negative effect of VEGF ablation on drug delivery and therapeutic response in anti-VEGF-resistant tumors. In conclusion, the vascular changes after anti-VEGF therapy can have a context-dependent negative impact on overall therapeutic efficacy. A determining factor is the tumor ECM, which strongly influences the effect of anti-VEGF therapy. Our results reveal the prospect to revert a possible negative effect and to potentiate responsiveness to antiangiogenic therapy by concomitantly targeting ECM-modifying enzymes. PMID:27270432

Expression and localization of the vascular endothelial growth factor and changes of microvessel density during hair follicle development of Liaoning cashmere goats.

PubMed

Zhang, Q L; Li, J P; Li, Y M; Chang, Q; Chen, Y; Jiang, H Z; Zhao, Z H; Guo, D

2013-12-10

Vascular endothelial growth factors (VEGFs) play important roles in neovascularization, tissue development, and angiogenesis. In this study, changes in VEGF expression patterns and microvessel density (MVD), and their correlations, were investigated during hair follicle development in epidermal appendages of Liaoning cashmere goats. Polyclonal antibodies to VEGF and microvessels were used for monthly immunohistochemical examinations of normal skin specimens from adult female goats for one year. VEGF was expressed in the hair bulb of primary and secondary hair follicles, the outer and inner root sheaths, sebaceous glands (ductal and secretory portions), eccrine sweat glands (ductal and secretory portions), and the epidermis. Abundant expression of VEGF was observed in the follicular basement membrane zone surrounding the bulb matrix and in ductal and secretory portions of eccrine sweat glands. The change in VEGFs in primary hair follicles showed a bimodal pattern, with the first peak observed from March to May, and the second in August. Maximal expression in secondary hair follicles occurred in May and August. Therefore, VEGF expression in primary and secondary hair follicles is synchronized throughout the year, and is correlated to hair development. In the later telogen and anagen phases, VEGF expression was higher in the secondary, compared to the primary, hair follicle. Changes in MVD also showed a bimodal pattern with peaks in May and August. VEGF expression and MVD showed moderate and strongly positive correlation in the primary and secondary hair follicles, respectively. Therefore, MVD and VEGF are closely related to the processes involved in hair cycle regulation.

VEGF-A is increased in exogenous endophthalmitis.

PubMed

Seamone, Mark E; Lewis, Darrell R; Haidl, Ian D; Gupta, R Rishi; O' Brien, Daniel M; Dickinson, John; Samad, Arif; Marshall, Jean S; Cruess, Alan F

2017-06-01

Exogenous endophthalmitis is an ophthalmologic emergency defined by panocular inflammation. Vascular endothelial growth factor A (VEGF-A) contributes to inflammation by promoting chemotaxis of monocytes and granulocytes and by increasing vascular permeability. The purpose of this article is to determine if VEGF-A is elevated in the vitreous samples obtained from individuals with exogenous endophthalmitis. Vitreous samples from individuals with exogenous endophthalmitis (n = 18) were analyzed via Luminex assay and enzyme-linked immunosorbent assay for the cytokines VEGF-A, tumor necrosis factor (TNF), interleukin 6 (IL-6), IL-8 (chemokine [CXCL]-8), IL-1β, IL-10, IL-12p70, IL-33, interferon (IFN)-γ, IFN-α, IFN-β, chemokine ligand (CCL)-3, IL-2, IL-5, IL-15, CXCL-10, CCL-2, IL-1Ra, CCL-5, IL-17, and CCL-11. Vitreous samples obtained at the time of macular hole surgery served as controls (n = 8). Concentrations of VEGF-A were significantly elevated in vitreous samples from individuals with exogenous endophthalmitis compared with macular hole (p < 0.001). VEGF-A was significantly upregulated in individuals with exogenous endophthalmitis after cataract surgery (p = 0.001), vitrectomy (p = 0.024), and intravitreal injection (p = 0.012). VEGF-A concentrations were similar in both culture-positive and culture-negative populations (p > 0.05). In a linear regression model, levels of VEGF-A correlated significantly with the chemokine CXCL-8 (p = 0.028). We demonstrate that VEGF-A is potently upregulated in exogenous endophthalmitis. This observation provides a foundation for future studies of targeted VEGF-A blockade in the management of endophthalmitis. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Novel Selective Detection Method of Tumor Angiogenesis Factors Using Living Nano-Robots.

PubMed

Al-Fandi, Mohamed; Alshraiedeh, Nida; Owies, Rami; Alshdaifat, Hala; Al-Mahaseneh, Omamah; Al-Tall, Khadijah; Alawneh, Rawan

2017-07-14

This paper reports a novel self-detection method for tumor cells using living nano-robots. These living robots are a nonpathogenic strain of E. coli bacteria equipped with naturally synthesized bio-nano-sensory systems that have an affinity to VEGF, an angiogenic factor overly-expressed by cancer cells. The VEGF-affinity/chemotaxis was assessed using several assays including the capillary chemotaxis assay, chemotaxis assay on soft agar, and chemotaxis assay on solid agar. In addition, a microfluidic device was developed to possibly discover tumor cells through the overexpressed vascular endothelial growth factor (VEGF). Various experiments to study the sensing characteristic of the nano-robots presented a strong response toward the VEGF. Thus, a new paradigm of selective targeting therapies for cancer can be advanced using swimming E. coli as self-navigator miniaturized robots as well as drug-delivery vehicles.

Pro- and antiangiogenic VEGF and its receptor status for the severity of diabetic retinopathy

PubMed Central

Mondal, Lakshmi K.; Borah, Prasanta K.; Bhattacharya, Chandra K.; Mahanta, Jagadish

2017-01-01

Purpose Alteration of pro- and antiangiogenic homeostasis of vascular endothelial growth factor (VEGF) isoforms in patients with hyperglycemia seems crucial but substantially unexplored at least quantitatively for diabetic retinopathy (DR). Therefore, in the present study we aimed to estimate the difference between the pro- (VEGF165a) and antiangiogenic (VEGF165b) VEGF isoforms and its soluble receptors for severity of DR. Methods The study included 123 participants (diabetic retinopathy: 81, diabetic control: 20, non-diabetic control: 22) from the Regional Institute of Ophthalmology, Kolkata. The protein levels of VEGF165a (proangiogenic), VEGF165b (antiangiogenic), VEGF receptor 1 (VEGFR1), VEGFR2, and VEGFR3 in plasma were determined with enzyme-linked immunosorbent assay (ELISA). Results An imbalance in VEGF homeostasis, a statistically significant concomitant increase (p<0.0001) in the level of VEGF165a and a decrease in the level of VEGF165b, was observed with the severity of the disease. Increased differences between VEGF165a and VEGF165b i.e. VEGF165a-b concomitantly increased statistically significantly with the severity of the disease (p<0.0001), patients with diffuse diabetic macular edema (DME) with proliferative DR (PDR) had the highest imbalance. The plasma soluble form of VEGFR2 concentration consistently increased statistically significantly with the severity of the disease (p<0.0001). Conclusions The increased difference or imbalance between the pro- (VEGF165a) and antiangiogenic (VEGF165b) homeostasis of the VEGF isoforms, seems crucial for an adverse prognosis of DR and may be a better explanatory marker compared with either VEGF isoform. PMID:28680264

VEGF promotes tumorigenesis and angiogenesis of human glioblastoma stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oka, Naoki; Soeda, Akio; Inagaki, Akihito

2007-08-31

There is increasing evidence for the presence of cancer stem cells (CSCs) in malignant brain tumors, and these CSCs may play a pivotal role in tumor initiation, growth, and recurrence. Vascular endothelial growth factor (VEGF) promotes the proliferation of vascular endothelial cells (VECs) and the neurogenesis of neural stem cells. Using CSCs derived from human glioblastomas and a retrovirus expressing VEGF, we examined the effects of VEGF on the properties of CSCs in vitro and in vivo. Although VEGF did not affect the property of CSCs in vitro, the injection of mouse brains with VEGF-expressing CSCs led to the massivemore » expansion of vascular-rich GBM, tumor-associated hemorrhage, and high morbidity, suggesting that VEGF promoted tumorigenesis via angiogenesis. These results revealed that VEGF induced the proliferation of VEC in the vascular-rich tumor environment, the so-called stem cell niche.« less

Soluble VEGF isoforms are essential for establishingepiphyseal vascularization and regulating chondrocyte development and survival

PubMed Central

Maes, Christa; Stockmans, Ingrid; Moermans, Karen; Van Looveren, Riet; Smets, Nico; Carmeliet, Peter; Bouillon, Roger; Carmeliet, Geert

2004-01-01

VEGF is crucial for metaphyseal bone vascularization. In contrast, the angiogenic factors required for vascularization of epiphyseal cartilage are unknown, although this represents a developmentally and clinically important aspect of bone growth. The VEGF gene is alternatively transcribed into VEGF120, VEGF164, and VEGF188 isoforms that differ in matrix association and receptor binding. Their role in bone development was studied in mice expressing single isoforms. Here we report that expression of only VEGF164 or only VEGF188 (in VEGF188/188 mice) was sufficient for metaphyseal development. VEGF188/188 mice, however, showed dwarfism, disrupted development of growth plates and secondary ossification centers, and knee joint dysplasia. This phenotype was at least partly due to impaired vascularization surrounding the epiphysis, resulting in ectopically increased hypoxia and massive chondrocyte apoptosis in the interior of the epiphyseal cartilage. In addition to the vascular defect, we provide in vitro evidence that the VEGF188 isoform alone is also insufficient to regulate chondrocyte proliferation and survival responses to hypoxia. Consistent herewith, chondrocytes in or close to the hypoxic zone in VEGF188/188 mice showed increased proliferation and decreased differentiation. These findings indicate that the insoluble VEGF188 isoform is insufficient for establishing epiphyseal vascularization and regulating cartilage development during endochondral bone formation. PMID:14722611

Soluble VEGF isoforms are essential for establishing epiphyseal vascularization and regulating chondrocyte development and survival.

PubMed

Maes, Christa; Stockmans, Ingrid; Moermans, Karen; Van Looveren, Riet; Smets, Nico; Carmeliet, Peter; Bouillon, Roger; Carmeliet, Geert

2004-01-01

VEGF is crucial for metaphyseal bone vascularization. In contrast, the angiogenic factors required for vascularization of epiphyseal cartilage are unknown, although this represents a developmentally and clinically important aspect of bone growth. The VEGF gene is alternatively transcribed into VEGF(120), VEGF(164), and VEGF(188) isoforms that differ in matrix association and receptor binding. Their role in bone development was studied in mice expressing single isoforms. Here we report that expression of only VEGF(164) or only VEGF(188) (in VEGF(188/188) mice) was sufficient for metaphyseal development. VEGF(188/188) mice, however, showed dwarfism, disrupted development of growth plates and secondary ossification centers, and knee joint dysplasia. This phenotype was at least partly due to impaired vascularization surrounding the epiphysis, resulting in ectopically increased hypoxia and massive chondrocyte apoptosis in the interior of the epiphyseal cartilage. In addition to the vascular defect, we provide in vitro evidence that the VEGF(188) isoform alone is also insufficient to regulate chondrocyte proliferation and survival responses to hypoxia. Consistent herewith, chondrocytes in or close to the hypoxic zone in VEGF(188/188) mice showed increased proliferation and decreased differentiation. These findings indicate that the insoluble VEGF(188) isoform is insufficient for establishing epiphyseal vascularization and regulating cartilage development during endochondral bone formation.

Beneficial effect of mechanical stimulation on the regenerative potential of muscle-derived stem cells is lost by inhibiting vascular endothelial growth factor.

PubMed

Beckman, Sarah A; Chen, William C W; Tang, Ying; Proto, Jonathan D; Mlakar, Logan; Wang, Bing; Huard, Johnny

2013-08-01

We previously reported that mechanical stimulation increased the effectiveness of muscle-derived stem cells (MDSCs) for tissue repair. The objective of this study was to determine the importance of vascular endothelial growth factor (VEGF) on mechanically stimulated MDSCs in a murine model of muscle regeneration. MDSCs were transduced with retroviral vectors encoding the LacZ reporter gene (lacZ-MDSCs), the soluble VEGF receptor Flt1 (sFlt1-MDSCs), or a short hairpin RNA (shRNA) targeting messenger RNA of VEGF (shRNA_VEGF MDSCs). Cells were subjected to 24 hours of mechanical cyclic strain and immediately transplanted into the gastrocnemius muscles of mdx/scid mice. Two weeks after transplantation, angiogenesis, fibrosis, and regeneration were analyzed. There was an increase in angiogenesis in the muscles transplanted with mechanically stimulated lacZ-MDSCs compared with nonstimulated lacZ-MDSCs, sFlt1-MDSCs, and shRNA _VEGF MDSCs. Dystrophin-positive myofiber regeneration was significantly lower in the shRNA_VEGF-MDSC group compared with the lacZ-MDSC and sFlt1-MDSC groups. In vitro proliferation of MDSCs was not decreased by inhibition of VEGF; however, differentiation into myotubes and adhesion to collagen were significantly lower in the shRNA_VEGF-MDSC group compared with the lacZ-MDSC and sFlt1-MDSC groups. The beneficial effects of mechanical stimulation on MDSC-mediated muscle repair are lost by inhibiting VEGF.

Beneficial Effect of Mechanical Stimulation on the Regenerative Potential of Muscle-Derived Stem Cells Is Lost by Inhibiting Vascular Endothelial Growth Factor

PubMed Central

Beckman, Sarah A.; Chen, William C.W.; Tang, Ying; Proto, Jonathan D.; Mlakar, Logan; Wang, Bing; Huard, Johnny

2016-01-01

Objective We previously reported that mechanical stimulation increased the effectiveness of muscle-derived stem cells (MDSCs) for tissue repair. The objective of this study was to determine the importance of vascular endothelial growth factor (VEGF) on mechanically stimulated MDSCs in a murine model of muscle regeneration. Approach and Results MDSCs were transduced with retroviral vectors encoding the LacZ reporter gene (lacZ-MDSCs), the soluble VEGF receptor Flt1 (sFlt1-MDSCs), or a short hairpin RNA (shRNA) targeting messenger RNA of VEGF (shRNA_VEGF MDSCs). Cells were subjected to 24 hours of mechanical cyclic strain and immediately transplanted into the gastrocnemius muscles of mdx/scid mice. Two weeks after transplantation, angiogenesis, fibrosis, and regeneration were analyzed. There was an increase in angiogenesis in the muscles transplanted with mechanically stimulated lacZMDSCs compared with nonstimulated lacZ-MDSCs, sFlt1-MDSCs, and shRNA _VEGF MDSCs. Dystrophin-positive myofiber regeneration was significantly lower in the shRNA_VEGF-MDSC group compared with the lacZ-MDSC and sFlt1-MDSC groups. In vitro proliferation of MDSCs was not decreased by inhibition of VEGF; however, differentiation into myotubes and adhesion to collagen were significantly lower in the shRNA_VEGF-MDSC group compared with the lacZ-MDSC and sFlt1-MDSC groups. Conclusions The beneficial effects of mechanical stimulation on MDSC-mediated muscle repair are lost by inhibiting VEGF. PMID:23723372

Vitamin C down-regulates VEGF production in B16F10 murine melanoma cells via the suppression of p42/44 MAPK activation.

PubMed

Kim, Ha Na; Kim, Hyemin; Kong, Joo Myung; Bae, Seyeon; Kim, Yong Sung; Lee, Naeun; Cho, Byung Joo; Lee, Seung Koo; Kim, Hang-Rae; Hwang, Young-il; Kang, Jae Seung; Lee, Wang Jae

2011-03-01

It is known that vitamin C induces apoptosis in several kinds of tumor cells, but its effect on the regulation of the angiogenic process of tumors is not completely studied. Vascular endothelial growth factor (VEGF) is the most well-known angiogenic factor, and it has a potent function as a stimulator of endothelial survival, migration, as well as vascular permeability. Therefore, we have investigated whether vitamin C can regulate the angiogenic process through the modulation of VEGF production from B16F10 melanoma cells. VEGF mRNA expression and VEGF production at protein levels were suppressed by vitamin C. In addition, we found that vitamin C suppressed the expression of cyclooxygenase (COX)-2 and that decreased VEGF production by vitamin C was also restored by the administration of prostaglandin E2 which is a product of COX-2. These results suggest that vitamin C suppresses VEGF expression via the regulation of COX-2 expression. Mitogen-activated protein kinases are generally known as key mediators in the signaling pathway for VEGF production. In the presence of vitamin C, the activation of p42/44 MAPK was completely inhibited. Taken together, our data suggest that vitamin C can down-regulate VEGF production via the modulation of COX-2 expression and that p42/44 MAPK acts as an important signaling mediator in this process. Copyright © 2010 Wiley-Liss, Inc.

The vascular permeabilizing factors histamine and serotonin induce angiogenesis through TR3/Nur77 and subsequently truncate it through thrombospondin-1

PubMed Central

Qin, Liuliang; Zhao, Dezheng; Xu, Jianfeng; Ren, Xianghui; Terwilliger, Ernest F.; Parangi, Sareh; Lawler, Jack; Dvorak, Harold F.

2013-01-01

Angiogenesis plays an important role in cancer and in many other human diseases. Vascular endothelial growth factor-A (VEGF-A), the best known angiogenic factor, was originally discovered as a potent vascular permeability factor (VPF), suggesting that other vascular permeabilizing agents, such as histamine and serotonin, might also have angiogenic activity. We recently demonstrated that, like VEGF-A, histamine and serotonin up-regulate the orphan nuclear receptor and transcription factor TR3 (mouse homolog Nur77) and that TR3/Nur77 is essential for their vascular permeabilizing activities. We now report that histamine and serotonin are also angiogenic factors that, at low micromolar concentrations, induce endothelial cell proliferation, migration and tube formation in vitro, and angiogenesis in vivo. All of these responses are mediated through specific histamine and serotonin receptors, are independent of VEGF-A, and are directly dependent on TR3/Nur77. Initially, the angiogenic response closely resembled that induced by VEGF-A, with generation of “mother” vessels. However, after ∼10 days, mother vessels began to regress as histamine and serotonin, unlike VEGF-A, up-regulated the potent angiogenesis inhibitor thrombospondin-1, thereby triggering a negative feedback loop. Thus, histamine and serotonin induce an angiogenic response that fits the time scale of acute inflammation. PMID:23315169

Dynamic regulation of VEGF-inducible genes by an ERK/ERG/p300 transcriptional network.

PubMed

Fish, Jason E; Cantu Gutierrez, Manuel; Dang, Lan T; Khyzha, Nadiya; Chen, Zhiqi; Veitch, Shawn; Cheng, Henry S; Khor, Melvin; Antounians, Lina; Njock, Makon-Sébastien; Boudreau, Emilie; Herman, Alexander M; Rhyner, Alexander M; Ruiz, Oscar E; Eisenhoffer, George T; Medina-Rivera, Alejandra; Wilson, Michael D; Wythe, Joshua D

2017-07-01

The transcriptional pathways activated downstream of vascular endothelial growth factor (VEGF) signaling during angiogenesis remain incompletely characterized. By assessing the signals responsible for induction of the Notch ligand delta-like 4 (DLL4) in endothelial cells, we find that activation of the MAPK/ERK pathway mirrors the rapid and dynamic induction of DLL4 transcription and that this pathway is required for DLL4 expression. Furthermore, VEGF/ERK signaling induces phosphorylation and activation of the ETS transcription factor ERG, a prerequisite for DLL4 induction. Transcription of DLL4 coincides with dynamic ERG-dependent recruitment of the transcriptional co-activator p300. Genome-wide gene expression profiling identified a network of VEGF-responsive and ERG-dependent genes, and ERG chromatin immunoprecipitation (ChIP)-seq revealed the presence of conserved ERG-bound putative enhancer elements near these target genes. Functional experiments performed in vitro and in vivo confirm that this network of genes requires ERK, ERG and p300 activity. Finally, genome-editing and transgenic approaches demonstrate that a highly conserved ERG-bound enhancer located upstream of HLX (which encodes a transcription factor implicated in sprouting angiogenesis) is required for its VEGF-mediated induction. Collectively, these findings elucidate a novel transcriptional pathway contributing to VEGF-dependent angiogenesis. © 2017. Published by The Company of Biologists Ltd.

Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

PubMed

Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

2017-08-17

Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

VEGF-B is dispensable for blood vessel growth but critical for their survival, and VEGF-B targeting inhibits pathological angiogenesis

PubMed Central

Zhang, Fan; Tang, Zhongshu; Hou, Xu; Lennartsson, Johan; Li, Yang; Koch, Alexander W.; Scotney, Pierre; Lee, Chunsik; Arjunan, Pachiappan; Dong, Lijin; Kumar, Anil; Rissanen, Tuomas T.; Wang, Bin; Nagai, Nobuo; Fons, Pierre; Fariss, Robert; Zhang, Yongqing; Wawrousek, Eric; Tansey, Ginger; Raber, James; Fong, Guo-Hua; Ding, Hao; Greenberg, David A.; Becker, Kevin G.; Herbert, Jean-Marc; Nash, Andrew; Yla-Herttuala, Seppo; Cao, Yihai; Watts, Ryan J.; Li, Xuri

2009-01-01

VEGF-B, a homolog of VEGF discovered a long time ago, has not been considered an important target in antiangiogenic therapy. Instead, it has received little attention from the field. In this study, using different animal models and multiple types of vascular cells, we revealed that although VEGF-B is dispensable for blood vessel growth, it is critical for their survival. Importantly, the survival effect of VEGF-B is not only on vascular endothelial cells, but also on pericytes, smooth muscle cells, and vascular stem/progenitor cells. In vivo, VEGF-B targeting inhibited both choroidal and retinal neovascularization. Mechanistically, we found that the vascular survival effect of VEGF-B is achieved by regulating the expression of many vascular prosurvival genes via both NP-1 and VEGFR-1. Our work thus indicates that the function of VEGF-B in the vascular system is to act as a “survival,” rather than an “angiogenic” factor and that VEGF-B inhibition may offer new therapeutic opportunities to treat neovascular diseases. PMID:19369214

SIX1 induces lymphangiogenesis and metastasis via upregulation of VEGF-C in mouse models of breast cancer

PubMed Central

Wang, Chu-An; Jedlicka, Paul; Patrick, Aaron N.; Micalizzi, Douglas S.; Lemmer, Kimberly C.; Deitsch, Erin; Casás-Selves, Matias; Harrell, J. Chuck; Ford, Heide L.

2012-01-01

An association between lymph node metastasis and poor prognosis in breast cancer was observed decades ago. However, the mechanisms by which tumor cells infiltrate the lymphatic system are not completely understood. Recently, it has been proposed that the lymphatic system has an active role in metastatic dissemination and that tumor-secreted growth factors stimulate lymphangiogenesis. We therefore investigated whether SIX1, a homeodomain-containing transcription factor previously associated in breast cancer with lymph node positivity, was involved in lymphangiogenesis and lymphatic metastasis. In a model in which human breast cancer cells were injected into immune-compromised mice, we found that SIX1 expression promoted peritumoral and intratumoral lymphangiogenesis, lymphatic invasion, and distant metastasis of breast cancer cells. SIX1 induced transcription of the prolymphangiogenic factor VEGF-C, and this was required for lymphangiogenesis and lymphatic metastasis. Using a mouse mammary carcinoma model, we found that VEGF-C was not sufficient to mediate all the metastatic effects of SIX1, indicating that SIX1 acts through additional, VEGF-C–independent pathways. Finally, we verified the clinical significance of this prometastatic SIX1/VEGF-C axis by demonstrating coexpression of SIX1 and VEGF-C in human breast cancer. These data define a critical role for SIX1 in lymphatic dissemination of breast cancer cells, providing a direct mechanistic explanation for how VEGF-C expression is upregulated in breast cancer, resulting in lymphangiogenesis and metastasis. PMID:22466647

Phenotypic and Gene Expression Modification with Normal Brain Aging in GFAP-Positive Astrocytes and Neural Stem Cells

PubMed Central

Bernal, Giovanna M.; Peterson, Daniel A.

2011-01-01

Summary Astrocytes secrete growth factors that are both neuroprotective and supportive for the local environment. Identified by glial fibrillary acidic protein (GFAP) expression, astrocytes exhibit heterogeneity in morphology and in expression of phenotypic markers and growth factors throughout different adult brain regions. In adult neurogenic niches, astrocytes secrete vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) within the neurogenic niche, and are also a source of special GFAP-positive multipotent neural stem cells (NSCs). Normal aging is accompanied by a decline in CNS function and reduced neurogenesis. We asked if a decreased availability of astrocyte-derived factors may contribute to the age-related decline in neurogenesis. Determining alterations of astrocytic activity in the aging brain is crucial for understanding CNS homeostasis in aging and for assessing appropriate therapeutic targets for an aging population. We found region-specific alterations in gene expression of GFAP, VEGF and FGF-2 and their receptors in the aged brain corresponding to changes in astrocytic reactivity, supporting astrocytic heterogeneity and demonstrating a differential aging effect. We found that GFAP-positive NSCs uniquely coexpress both VEGF and its key mitotic receptor Flk-1 in both young and aged hippocampus, indicating a possible autocrine/paracrine signaling mechanism. VEGF expression is lost once NSCs commit to a neuronal fate, but Flk-1-mediated sensitivity to VEGF signaling is maintained. We propose that age-related astrocytic changes result in reduced VEGF and FGF-2 signaling, which in turn limits neural stem cell and progenitor cell maintenance and contributes to decreased neurogenesis. PMID:21385309

Diagnostic values of vascular endothelial growth factor and epidermal growth factor receptor for benign and malignant hydrothorax.

PubMed

Gu, Yan; Zhang, Min; Li, Guo-Hua; Gao, Jun-Zhen; Guo, Liping; Qiao, Xiao-Juan; Wang, Li-Hong; He, Lan; Wang, Mei-Ling; Yan, Li; Fu, Xiu-Hua

2015-02-05

Hydrothorax, as one of the common complications of malignant tumors, still cannot be sensitively detected in clinical practice, thus requiring a sensitive, specific method for diagnosis. The aim of this study was to analyze the correlation between levels of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) in patients with benign and malignant hydrothorax. The contents of VEGF in the pleural effusion and serum of the patients with malignant pleural effusion (n = 35) and benign pleural effusion (n = 30) were detected by double antibody sandwich enzyme linked immunosorbent assay. The gene copy number level of EGFR in pleural effusion was detected by fluorescence in situ hybridization (FISH). The points with the highest sensitivity and specificity were selected as the critical values to calculate the diagnostic value of the VEGF in pleural effusion and serum, and EGFR gene copy number in pleural effusion. The contents of VEGF in pleural effusion and serum of patients with malignant hydrothorax were (384.91 ± 120.18), and (129.62 ± 46.35) ng/L, respectively, which were significantly higher than those of the patients with benign hydrothorax (207.97 ± 64.04), (63.49 ± 24.58) ng/L (P < 0.01). The sensitivity and specificity of detecting VEGF in pleural effusion were 80.0% and 96.7% (the boundary value was 297.06 ng/L), respectively for diagnosing benign and malignant hydrothorax. The sensitivity and specificity of serum were 74.3% and 96.7%, respectively (the boundary value was 99.21 ng/L) for diagnosing benign and malignant hydrothorax. The diagnostic efficiencies of EGFR and VEGF in hydrothorax were similar. There was a significant correlation between EGFR and VEGF in hydrothorax (P < 0.01). VEGF and EGFR play important roles in the formation of pleural effusion. VEGF differed significantly in benign and malignant pleural effusions, which contributed to differential diagnosis results of benign and malignant pleural effusions. It is feasible to detect the gene copy number of the pleural effusion cell mass EGFR by FISH technique. Joint detection can improve the diagnostic sensitivity.

Diagnostic Values of Vascular Endothelial Growth Factor and Epidermal Growth Factor Receptor for Benign and Malignant Hydrothorax

PubMed Central

Gu, Yan; Zhang, Min; Li, Guo-Hua; Gao, Jun-Zhen; Guo, Liping; Qiao, Xiao-Juan; Wang, Li-Hong; He, Lan; Wang, Mei-Ling; Yan, Li; Fu, Xiu-Hua

2015-01-01

Background: Hydrothorax, as one of the common complications of malignant tumors, still cannot be sensitively detected in clinical practice, thus requiring a sensitive, specific method for diagnosis. The aim of this study was to analyze the correlation between levels of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) in patients with benign and malignant hydrothorax. Methods: The contents of VEGF in the pleural effusion and serum of the patients with malignant pleural effusion (n = 35) and benign pleural effusion (n = 30) were detected by double antibody sandwich enzyme linked immunosorbent assay. The gene copy number level of EGFR in pleural effusion was detected by fluorescence in situ hybridization (FISH). The points with the highest sensitivity and specificity were selected as the critical values to calculate the diagnostic value of the VEGF in pleural effusion and serum, and EGFR gene copy number in pleural effusion. Results: The contents of VEGF in pleural effusion and serum of patients with malignant hydrothorax were (384.91 ± 120.18), and (129.62 ± 46.35) ng/L, respectively, which were significantly higher than those of the patients with benign hydrothorax (207.97 ± 64.04), (63.49 ± 24.58) ng/L (P < 0.01). The sensitivity and specificity of detecting VEGF in pleural effusion were 80.0% and 96.7% (the boundary value was 297.06 ng/L), respectively for diagnosing benign and malignant hydrothorax. The sensitivity and specificity of serum were 74.3% and 96.7%, respectively (the boundary value was 99.21 ng/L) for diagnosing benign and malignant hydrothorax. The diagnostic efficiencies of EGFR and VEGF in hydrothorax were similar. There was a significant correlation between EGFR and VEGF in hydrothorax (P < 0.01). Conclusions: VEGF and EGFR play important roles in the formation of pleural effusion. VEGF differed significantly in benign and malignant pleural effusions, which contributed to differential diagnosis results of benign and malignant pleural effusions. It is feasible to detect the gene copy number of the pleural effusion cell mass EGFR by FISH technique. Joint detection can improve the diagnostic sensitivity. PMID:25635424

Effect of peritoneal dialysis on expression of vascular endothelial growth factor, basic fibroblast growth factor and endostatin of the peritoneum in peritoneal dialysis patients.

PubMed

Gao, Dan; Zhao, Zhan-Zheng; Liang, Xian-Hui; Li, Yan; Cao, Ying; Liu, Zhang-Suo

2011-11-01

The aim of this study is to investigate the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endostatin (ES) in human peritoneum and investigate the relationship between them and peritoneum neoangiogensis in the patients with uraemia and peritoneal dialysis (PD). Peritoneal biopsies were obtained from normal subjects (n = 8), uraemic predialysis patients (n = 12) and PD patients (n = 10). The mRNA expression of VEGF, bFGF and ES in peritoneal tissues were measured through real-time polymerase chain reaction. The protein expression of VEGF, bFGF and ES in peritoneal tissues were determined through western blot. Microvessel density (MVD) of peritoneal tissue was assessed using immunohistochemistry with CD34 monoclonal antibody. The mRNA and protein of VEGF, bFGF and ES were expressed in all peritoneal samples. Compared with the normal control group, the mRNA and protein expression of VEGF and bFGF in peritoneal tissues were all significantly upregulated in the uraemic predialysis and PD group (all P < 0.05). Compared with the normal control group, the protein expression of ES were significantly upregulated in the uraemic predialysis and PD group (all (P < 0.05), but the mRNA expression of ES did not have obvious differences in the uraemic predialysis and PD group as compared to the normal control group (P > 0.05). MVD of peritoneal tissue were increased in the uraemic predialysis and PD group compared with the normal group (all P < 0.05). A significant positive correlation was found between VEGF mRNA expression and MVD, bFGF mRNA expression and MVD. The mRNA expression of VEGF and bFGF, the protein expression of VEGF, bFGF, and ES and microvessel density (MVD) are increased both in the uraemic predialysis and PD patients. These results show that uraemia circumstances and non-physiological compatibility of peritoneal dialysis solution might increase VEGF, bFGF and ES expression and MVD, which might participate in the increment of the peritoneum neoangiogensis and ultrafiltration failure in PD patients. © 2011 The Authors. Nephrology © 2011 Asian Pacific Society of Nephrology.

Vascular Endothelial Growth Factor Augments Arginine Transport and Nitric Oxide Generation via a KDR Receptor Signaling Pathway.

PubMed

Shashar, Moshe; Chernichovski, Tamara; Pasvolsky, Oren; Levi, Sharon; Grupper, Ayelet; Hershkovitz, Rami; Weinstein, Talia; Schwartz, Idit F

2017-01-01

Vascular endothelial growth factor (VEGF) is an endothelium-specific peptide that stimulates angiogenesis via two receptor tyrosine kinases, Flt-1 and KDR. Endothelial nitric oxide synthase (eNOS) plays a major role in VEGF signaling. Delivery of arginine to membrane bound eNOS by the cationic amino acid transporter-1 (CAT-1) has been shown to modulate eNOS activity. The current studies were designed to test the hypothesis that VEGF enhances eNOS activity via modulation of arginine transport by CAT-1. Using radio-labeled arginine, {[3H] L-arginine} uptake was determined in human umbilical vein endothelial cells (HUVEC) following incubation with VEGF with and without silencing the VEGF receptors Flt-1 or KDR. Subsequently, western blotting for CAT-1, PKCα, ERK 1/2, JNK, and their phosphorylated forms were performed. NO generation was measured by the Griess reaction. VEGF (50 and 100 ng/ml) significantly augmented endothelial arginine transport in a time dependent manner, an effect which was prevented by Sunitinib (2 µM), a multi targeted receptor tyrosine kinase inhibitor. The increase in arginine transport velocities by VEGF was not affected by silencing Flt-1 while silencing KDR abrogated VEGF effect. Furthermore, incubating cells with 50 and 100 ng of VEGF for 30 minutes significantly augmented CAT-1 abundance. The expression of PKC-α, JNK, and ERK1/2 and their phosphorylated forms were unchanged following incubation of HUVEC with VEGF. The concentration of NO2/NO3 following incubation with VEGF was significantly higher than from untreated cells. This increase was significantly attenuated by silencing KDR. VEGF increases arginine transport via modulation of CAT-1 in endothelial cells. This effect is exclusively dependent on KDR rather than Flt-1. © 2017 The Author(s). Published by S. Karger AG, Basel.

Stretch-Induced Hypertrophy Activates NFkB-Mediated VEGF Secretion in Adult Cardiomyocytes

PubMed Central

Leychenko, Anna; Konorev, Eugene; Jijiwa, Mayumi; Matter, Michelle L.

2011-01-01

Hypertension and myocardial infarction are associated with the onset of hypertrophy. Hypertrophy is a compensatory response mechanism to increases in mechanical load due to pressure or volume overload. It is characterized by extracellular matrix remodeling and hypertrophic growth of adult cardiomyocytes. Production of Vascular Endothelial Growth Factor (VEGF), which acts as an angiogenic factor and a modulator of cardiomyocyte function, is regulated by mechanical stretch. Mechanical stretch promotes VEGF secretion in neonatal cardiomyocytes. Whether this effect is retained in adult cells and the molecular mechanism mediating stretch-induced VEGF secretion has not been elucidated. Our objective was to investigate whether cyclic mechanical stretch induces VEGF secretion in adult cardiomyocytes and to identify the molecular mechanism mediating VEGF secretion in these cells. Isolated primary adult rat cardiomyocytes (ARCMs) were subjected to cyclic mechanical stretch at an extension level of 10% at 30 cycles/min that induces hypertrophic responses. Cyclic mechanical stretch induced a 3-fold increase in VEGF secretion in ARCMs compared to non-stretch controls. This increase in stretch-induced VEGF secretion correlated with NFkB activation. Cyclic mechanical stretch-mediated VEGF secretion was blocked by an NFkB peptide inhibitor and expression of a dominant negative mutant IkBα, but not by inhibitors of the MAPK/ERK1/2 or PI3K pathways. Chromatin immunoprecipitation assays demonstrated an interaction of NFkB with the VEGF promoter in stretched primary cardiomyocytes. Moreover, VEGF secretion is increased in the stretched myocardium during pressure overload-induced hypertrophy. These findings are the first to demonstrate that NFkB activation plays a role in mediating VEGF secretion upon cyclic mechanical stretch in adult cardiomyocytes. Signaling by NFkB initiated in response to cyclic mechanical stretch may therefore coordinate the hypertrophic response in adult cardiomyocytes. Elucidation of this novel mechanism may provide a target for developing future pharmacotherapy to treat hypertension and heart disease. PMID:22174951

Serum Levels of Vascular Endothelial Growth Factor and Insulin-like Growth Factor Binding Protein-3 in Obstructive Sleep Apnea Patients: Effect of Continuous Positive Airway Pressure Treatment

PubMed Central

Archontogeorgis, Kostas; Nena, Evangelia; Papanas, Nikolaos; Xanthoudaki, Maria; Hatzizisi, Olga; Kyriazis, Georgios; Tsara, Venetia; Maltezos, Efstratios; Froudarakis, Marios; Steiropoulos, Paschalis

2015-01-01

Background and Aim: Hypoxia, a major feature of obstructive sleep apnea (OSA), modifies Vascular Endothelial Growth Factor (VEGF) and Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) levels, which contribute to atherogenesis and occurrence of cardiovascular (CV) events. We assessed and compared serum levels of VEGF and IGFBP-3 in newly diagnosed OSA patients and controls, to explore associations with anthropometric and sleep parameters and to study the effect of continuous positive airway pressure (CPAP) treatment on these levels. Materials and Methods: Serum levels of VEGF and IGFBP-3 were measured in 65 OSA patients and 31 age- and body mass index- matched controls. In OSA patients, measurements were repeated after 6 months of CPAP therapy. All participants were non-smokers, without any comorbidities or systemic medication use. Results: At baseline, serum VEGF levels in OSA patients were higher compared with controls (p<0.001), while IGFBP-3 levels were lower (1.41±0.56 vs. 1.61±0.38 μg/ml, p=0.039). VEGF levels correlated with apnea-hypopnea index (r=0.336, p=0.001) and oxygen desaturation index (r=0.282, p=0.007). After 6 months on CPAP treatment, VEGF levels decreased in OSA patients (p<0.001), while IGFBP-3 levels increased (p<0.001). Conclusion: In newly diagnosed OSA patients, serum levels of VEGF are elevated, while IGFBP-3 levels are low. After 6 months of CPAP treatment these levels change. These results may reflect an increased CV risk in untreated OSA patients, which is ameliorated after CPAP therapy. PMID:27006717

Angiogenic Capacity of Periodontal Ligament Stem Cells Pretreated with Deferoxamine and/or Fibroblast Growth Factor-2

PubMed Central

Ratajczak, Jessica; Hilkens, Petra; Gervois, Pascal; Wolfs, Esther; Jacobs, Reinhilde; Lambrichts, Ivo; Bronckaers, Annelies

2016-01-01

Periodontal ligament stem cells (PDLSCs) represent a good source of multipotent cells for cell-based therapies in regenerative medicine. The success rate of these treatments is severely dependent on the establishment of adequate vasculature in order to provide oxygen and nutrients to the transplanted cells. Pharmacological preconditioning of stem cells has been proposed as a promising method to augment their therapeutic efficacy. In this study, the aim was to improve the intrinsic angiogenic properties of PDLSCs by in vitro pretreatment with deferoxamine (DFX; 100μM), fibroblast growth factor-2 (FGF-2; 10ng/mL) or both substances combined. An antibody array revealed the differential expression of several proteins, including vascular endothelial growth factor (VEGF) and placental growth factor (PlGF). ELISA data confirmed a 1.5 to 1.8-fold increase in VEGF for all tested conditions. Moreover, 48 hours after the removal of DFX, VEGF levels remained elevated (1.8-fold) compared to control conditions. FGF-2 and combination treatment resulted in a 5.4 to 13.1-fold increase in PlGF secretion, whereas DFX treatment had no effect. Furthermore, both PDLSCs as pretreated PDLSCs induced endothelial migration. Despite the significant elevated VEGF levels of pretreated PDLSCs, the induced endothelial migration was not higher by pretreated PDLSCs. We find that the observed induced endothelial cell motility was not dependent on VEGF, since blocking the VEGFR1-3 with Axitinib (0.5nM) did not inhibit endothelial motility towards PDLSCs. Taken together, this study provides evidence that preconditioning with DFX and/or FGF-2 significantly improves the angiogenic secretome of PDLSCs, in particular VEGF and PlGF secretion. However, our data suggest that VEGF is not the only player when it comes to influencing endothelial behavior by the PDLSCs. PMID:27936076

Impact of continuous positive airway pressure on vascular endothelial growth factor in patients with obstructive sleep apnea: a meta-analysis.

PubMed

Qi, Jia-Chao; Zhang, LiangJi; Li, Hao; Zeng, Huixue; Ye, Yuming; Wang, Tiezhu; Wu, Qiyin; Chen, Lida; Xu, Qiaozhen; Zheng, Yifeng; Huang, Yaping; Lin, Li

2018-04-18

Cumulative evidence supports the clear relationship of obstructive sleep apnea (OSA) with cardiovascular disease (CVD). And, adherence to continuous positive airway pressure (CPAP) treatment alleviates the risk of CVD in subjects with OSA. Vascular endothelial growth factor (VEGF), a potent angiogenic cytokine regulated by hypoxia-inducible factor, stimulates the progression of CVD. Thus, whether treatment with CPAP can actually decrease VEGF in patients with OSA remains inconclusive. The purpose of the present study was to quantitatively evaluate the impact of CPAP therapy on VEGF levels in OSA patients. We systematically searched Web of Science, Cochrane Library, PubMed, and Embase databases that examined the impact of CPAP on VEGF levels in OSA patients prior to May 1, 2017. Related searching terms were "sleep apnea, obstructive," "sleep disordered breathing," "continuous positive airway pressure," "positive airway pressure," and "vascular endothelial growth factor." We used standardized mean difference (SMD) to analyze the summary estimates for CPAP therapy. Six studies involving 392 patients were eligible for the meta-analysis. Meta-analysis of the pooled effect showed that levels of VEGF were significantly decreased in patients with OSA before and after CPAP treatment (SMD = - 0.440, 95% confidence interval (CI) = - 0.684 to - 0.196, z = 3.53, p = 0.000). Further, results demonstrated that differences in age, body mass index, apnea-hypopnea index, CPAP therapy duration, sample size, and racial differences also affected CPAP efficacy. Improved endothelial function measured by VEGF may be associated with CPAP therapy in OSA patients. The use of VEGF levels may be clinically important in evaluating CVD for OSA patients. Further large-scale, well-designed long-term interventional investigations are needed to clarify this issue.

Prognostic Significance of Vascular Endothelial Growth Factor (VEGF) and Her-2 Protein in the Genesis of Cervical Carcinoma.

PubMed

Rahmani, Arshad H; Babiker, Ali Yousif; Alsahli, Mohammed A; Almatroodi, Saleh A; Husain, Nazik Elmalaika O S

2018-02-15

Angiogenesis plays a pivotal role in the progression of tumours through the formation of new blood vessels. Vascular endothelial growth factor (VEGF) is a chief factor responsible for inducing and regulating angiogenesis. Additionally, the human epidermal growth factor receptor family of receptors also plays an important role in the pathogenesis of tumours. This study aimed to examine the association between VEGF and Her-2 protein expression and its correlation with clinic-pathological characteristics; in particular, prognosis. A total of 65 cases of cervical carcinoma and 10 samples of inflammatory lesions were evaluated for VEGF and Her-2 protein expression. Expression of VEGF and Her-2 was detected in 63.07% and 43.07% in cervical carcinoma cases respectively whereas control cases did not show any expression. The difference in the expression pattern of both markers comparing cancer and control cases was statistically significant (p < 0.05). However, no significant difference in the expression pattern of VEGF protein was observed among the different grades and stages of tumours (p > 0.05). Comparing different grades of a tumour, expression of Her-2 was detected in 31.8% of well-differentiated tumours, 36.0 % in moderately differentiated tumours and 66.66 % in poorly differentiated cancers. The expression of Her-2 was increased in high-grade tumours, and the difference of expression level between tumour grades was statistically significant (p < 0.05). The expression level of Her-2 protein was not correlated with the stage of a tumour (p > 0.05). The present study supports earlier findings that over-expression / up-regulation of VEGF and Her - 2 is linked with poor prognosis and may play a vital role in the development and progression of cervical cancer.

Prognostic Significance of Vascular Endothelial Growth Factor (VEGF) and Her-2 Protein in the Genesis of Cervical Carcinoma

PubMed Central

Rahmani, Arshad H.; Babiker, Ali Yousif; Alsahli, Mohammed A.; Almatroodi, Saleh A.; Husain, Nazik Elmalaika O. S.

2018-01-01

BACKGROUND: Angiogenesis plays a pivotal role in the progression of tumours through the formation of new blood vessels. Vascular endothelial growth factor (VEGF) is a chief factor responsible for inducing and regulating angiogenesis. Additionally, the human epidermal growth factor receptor family of receptors also plays an important role in the pathogenesis of tumours. AIM: This study aimed to examine the association between VEGF and Her-2 protein expression and its correlation with clinic-pathological characteristics; in particular, prognosis. METHODS: A total of 65 cases of cervical carcinoma and 10 samples of inflammatory lesions were evaluated for VEGF and Her-2 protein expression. RESULTS: Expression of VEGF and Her-2 was detected in 63.07% and 43.07% in cervical carcinoma cases respectively whereas control cases did not show any expression. The difference in the expression pattern of both markers comparing cancer and control cases was statistically significant (p < 0.05). However, no significant difference in the expression pattern of VEGF protein was observed among the different grades and stages of tumours (p > 0.05). Comparing different grades of a tumour, expression of Her-2 was detected in 31.8% of well-differentiated tumours, 36.0 % in moderately differentiated tumours and 66.66 % in poorly differentiated cancers. The expression of Her-2 was increased in high-grade tumours, and the difference of expression level between tumour grades was statistically significant (p < 0.05). The expression level of Her-2 protein was not correlated with the stage of a tumour (p > 0.05). CONCLUSION: The present study supports earlier findings that over-expression / up-regulation of VEGF and Her - 2 is linked with poor prognosis and may play a vital role in the development and progression of cervical cancer. PMID:29531585

Vascular endothelial growth factor modified macrophages transdifferentiate into endothelial-like cells and decrease foam cell formation.

PubMed

Yan, Dan; He, Yujuan; Dai, Jun; Yang, Lili; Wang, Xiaoyan; Ruan, Qiurong

2017-06-30

Macrophages are largely involved in the whole process of atherosclerosis from an initiation lesion to an advanced lesion. Endothelial disruption is the initial step and macrophage-derived foam cells are the hallmark of atherosclerosis. Promotion of vascular integrity and inhibition of foam cell formation are two important strategies for preventing atherosclerosis. How can we inhibit even the reverse negative role of macrophages in atherosclerosis? The present study was performed to investigate if overexpressing endogenous human vascular endothelial growth factor (VEGF) could facilitate transdifferentiation of macrophages into endothelial-like cells (ELCs) and inhibit foam cell formation. We demonstrated that VEGF-modified macrophages which stably overexpressed human VEGF (hVEGF 165 ) displayed a high capability to alter their phenotype and function into ELCs in vitro Exogenous VEGF could not replace endogenous VEGF to induce the transdifferentiation of macrophages into ELCs in vitro We further showed that VEGF-modified macrophages significantly decreased cytoplasmic lipid accumulation after treatment with oxidized LDL (ox-LDL). Moreover, down-regulation of CD36 expression in these cells was probably one of the mechanisms of reduction in foam cell formation. Our results provided the in vitro proof of VEGF-modified macrophages as atheroprotective therapeutic cells by both promotion of vascular repair and inhibition of foam cell formation. © 2017 The Author(s).

Decursin inhibits VEGF-mediated inner blood-retinal barrier breakdown by suppression of VEGFR-2 activation.

PubMed

Kim, Jin Hyoung; Kim, Jeong Hun; Lee, You Mie; Ahn, Eun-Mi; Kim, Kyu-Won; Yu, Young Suk

2009-09-01

The blood-retinal barrier (BRB) is essential for the normal structural and functional integrity of the retina, whose breakdown could cause the serious vision loss. Vascular endothelial growth factor (VEGF), as a permeable factor, induces alteration of tight junction proteins to result in BRB breakdown. Herein, we demonstrated that decursin inhibits VEGF-mediated inner BRB breakdown through suppression of VEGFR-2 signaling pathway. In retinal endothelial cells, decursin inhibited VEGF-mediated hyperpermeability. Decursin prevented VEGF-mediated loss of tight junction proteins including zonula occludens-1 (ZO-1), ZO-2, and occludin in retinal endothelial cells, which was also supported by restoration of tight junction proteins in intercellular junction. In addition, decursin significantly inhibited VEGF-mediated vascular leakage from retinal vessels, which was accompanied by prevention of loss of tight junction proteins in retinal vessels. Decursin significantly suppressed VEGF-induced VEGFR-2 phosphrylation that consequently led to inhibition of extracellular signal-regulated kinase (ERK) 1/2 activation. Moreover, decursin induced no cytotoxicity to retinal endothelial cells and no retinal toxicity under therapeutic concentrations. Therefore, our results suggest that decursin prevents VEGF-mediated BRB breakdown through blocking of loss of tight junction proteins, which might be regulated by suppression of VEGFR-2 activation. As a novel inhibitor to BRB breakdown, decursin could be applied to variable retinopathies with BRB breakdown.

[Fluocinolone acetonide (ILUVIEN®) micro-implant for chronic diabetic macular edema].

PubMed

Soubrane, G; Behar-Cohen, F

2015-02-01

Diabetic macular edema (DME) is a frequent complication of diabetic retinopathy and may cause severe visual loss. In this article, we examine the pathophysiology of DME and review various treatment options, such as laser photocoagulation, anti-vascular endothelial growth factor (VEGF) receptor antibodies, and steroids including ILUVIEN(®), which is a new sustained-release, non biodegradable, injectable, intravitreal micro-implant containing fluocinolone acetonide. The results of the FAME (Fluocinolone Acetonide in Diabetic Macular Edema) studies, conducted to evaluate the efficacy and safety of ILUVIEN(®) in DME, are discussed. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Baicalin increases VEGF expression and angiogenesis by activating the ERRα/PGC-1α pathway

PubMed Central

Zhang, Keqiang; Lu, Jianming; Mori, Taisuke; Smith-Powell, Leslie; Synold, Timothy W.; Chen, Shiuan; Wen, Wei

2011-01-01

Aims Baicalin is the major component found in Scutellaria baicalensis root, a widely used herb in traditional Chinese medicine. Although it has been used for thousands of years to treat stroke, the mechanisms of action of S. baicalensis have not been clearly elucidated. In this report, we studied the modulation of angiogenesis as one possible mechanism by investigating the effects of these agents on expression of vascular endothelial growth factor (VEGF), a critical factor for angiogenesis. Methods and results The effects of baicalin and an extract of S. baicalensis on VEGF expression were tested in several cell lines. Both agents induced VEGF expression in all cells without increasing expression of hypoxia-inducible factor-1α (HIF-1α). The expression of reporter genes was also activated under the control of the VEGF promoter containing either a functional or a defective HIF response element (HRE). Only minimal effects were observed on reporter activation under the HRE promoter. Instead, both agents significantly induced oestrogen-related receptor (ERRα) expression as well as the activity of reporter genes under the control of ERRα-binding element. Their ability to induce VEGF expression was suppressed once ERRα expression was knocked down by siRNA or ERRα-binding sites were deleted in the VEGF promoter. We also found that both agents stimulated cell migration and vessel sprout formation from the aorta. Conclusion Our results implicate baicalin and S. baicalensis in angiogenesis by inducing VEGF expression through the activation of the ERRα pathway. These data may facilitate a better understanding of the potential health benefits of these agents in the treatment of cardiovascular diseases. PMID:20851810

Inositol Polyphosphate Multikinase Inhibits Angiogenesis via Inositol Pentakisphosphate-Induced HIF-1α Degradation.

PubMed

Fu, Chenglai; Tyagi, Richa; Chin, Alfred C; Rojas, Tomas; Li, Ruo-Jing; Guha, Prasun; Bernstein, Isaac A; Rao, Feng; Xu, Risheng; Cha, Jiyoung Y; Xu, Jing; Snowman, Adele M; Semenza, Gregg L; Snyder, Solomon H

2018-02-02

Inositol polyphosphate multikinase (IPMK) and its major product inositol pentakisphosphate (IP5) regulate a variety of cellular functions, but their role in vascular biology remains unexplored. We have investigated the role of IPMK in regulating angiogenesis. Deletion of IPMK in fibroblasts induces angiogenesis in both in vitro and in vivo models. IPMK deletion elicits a substantial increase of VEGF (vascular endothelial growth factor), which mediates the regulation of angiogenesis by IPMK. The regulation of VEGF by IPMK requires its catalytic activity. IPMK is predominantly nuclear and regulates gene transcription. However, IPMK does not apparently serve as a transcription factor for VEGF. HIF (hypoxia-inducible factor)-1α is a major determinant of angiogenesis and induces VEGF transcription. IPMK deletion elicits a major enrichment of HIF-1α protein and thus VEGF. HIF-1α is constitutively ubiquitinated by pVHL (von Hippel-Lindau protein) followed by proteasomal degradation under normal conditions. However, HIF-1α is not recognized and ubiquitinated by pVHL in IPMK KO (knockout) cells. IP5 reinstates the interaction of HIF-1α and pVHL. HIF-1α prolyl hydroxylation, which is prerequisite for pVHL recognition, is interrupted in IPMK-deleted cells. IP5 promotes HIF-1α prolyl hydroxylation and thus pVHL-dependent degradation of HIF-1α. Deletion of IPMK in mouse brain increases HIF-1α/VEGF levels and vascularization. The increased VEGF in IPMK KO disrupts blood-brain barrier and enhances brain blood vessel permeability. IPMK, via its product IP5, negatively regulates angiogenesis by inhibiting VEGF expression. IP5 acts by enhancing HIF-1α hydroxylation and thus pVHL-dependent degradation of HIF-1α. © 2017 American Heart Association, Inc.

Novel angiogenesis inhibitory activity in cinnamon extract blocks VEGFR2 kinase and downstream signaling

USDA-ARS?s Scientific Manuscript database

VEGF is one of the most critical factors that induce angiogenesis, and has thus become an attractive target for anti-angiogenesis treatment. However, most of the current anti-VEGF agents that often cause side effects cannot be recommended for long term use. Identification of natural VEGF inhibitors...

From the discovery of vascular endothelial growth factor to the introduction of avastin in clinical trials - an interview with Napoleone Ferrara by Domenico Ribatti.

PubMed

Ferrara, Napoleone

2011-01-01

Napoleone Ferrara and his colleagues at Genentech were the first to isolate and clone vascular endothelial growth factor (VEGF) in 1989. His laboratory has investigated many aspects of VEGF biochemistry and molecular biology. In 1993, Ferrara reported that inhibition of VEGF-induced angiogenesis by specific monoclonal antibodies resulted in dramatic suppression of the growth of a variety of tumors in vivo. These findings provided an important evidence that inhibition of angiogenesis may suppress tumor growth and blocking VEGF action could have therapeutic value for a variety of malignancies. A further development was the design in a rational fashion in 1997 of a humanized anti-VEGF monoclonal antibody (Avastin), now in clinical trials as a treatment for several solid tumors and also outside of cancer, in the treatment of age-related macular degeneration (AMD). Ferrara's work is revolutionizing quality of life for many of the estimated 1.2 million individuals in the US who have wet AMD. Upwards of a million AMD patients worldwide have already received anti-VEGF antibody therapy.

Enforced expression of KDR receptor promotes proliferation, survival and megakaryocytic differentiation of TF1 progenitor cell line.

PubMed

Coppola, S; Narciso, L; Feccia, T; Bonci, D; Calabrò, L; Morsilli, O; Gabbianelli, M; De Maria, R; Testa, U; Peschle, C

2006-01-01

Vascular endothelial growth factor (VEGF) receptor-2/kinase insert domain-containing receptor (KDR) is expressed in primitive hematopoietic cells, in megakaryocytes and platelets. In primitive hematopoiesis KDR mediates cell survival via autocrine VEGF, while its effect on cell growth and differentiation has not been elucidated. We induced enforced KDR expression in the granulocyte macrophage-colony-stimulating factor (GM-CSF)-dependent TF1 progenitor cell line (TF1-KDR), treated the cells with VEGF and analyzed their response. In GM-CSF-deprived cells, VEGF induces cell proliferation and protection against apoptosis, followed by enhanced expression of megakaryocytic (MK) markers. Combined with GM-CSF, VEGF induces a mild proliferative stimulus, followed by cell adherence, accumulation in G0/G1, massive MK differentiation and Fas-mediated apoptosis. Accordingly, we observed that MK-differentiating cells, derived from hematopoietic progenitors, produce VEGF, express KDR, inhibition of which reduces MK differentiation, indicating a key role of KDR in megakaryopoiesis. In conclusion, TF1-KDR cells provide a reliable model to investigate the biochemical and molecular mechanisms underlying hematopoietic progenitor proliferation, survival and MK differentiation.

In vitro therapeutic effect of PDT combined with VEGF-A gene therapy

NASA Astrophysics Data System (ADS)

Lecaros, Rumwald Leo G.; Huang, Leaf; Hsu, Yih-Chih

2014-02-01

Vascular endothelial growth factor A (VEGF-A), commonly known as VEGF, is one of the primary factors that affect tumor angiogenesis. It was found to be expressed in cancer cell lines including oral squamous cell carcinoma. Photodynamic therapy (PDT) is a novel therapeutic modality to treat cancer by using a photosensitizer which is activated by a light source to produce reactive oxygen species and mediates oxygen-independent hypoxic conditions to tumor. Another emerging treatment to cure cancer is the use of interference RNA (e.g. siRNA) to silence a specific mRNA sequence. VEGF-A was found to be expressed in oral squamous cell carcinoma and overexpressed after 24 hour post-PDT by Western blot analysis. Cell viability was found to decrease at 25 nM of transfected VEGF-A siRNA. In vitro combined therapy of PDT and VEGF-A siRNA showed better response as compared with PDT and gene therapy alone. The results suggest that PDT combined with targeted gene therapy has a potential mean to achieve better therapeutic outcome.

Cellular and molecular mechanisms of age-related macular degeneration: from impaired autophagy to neovascularization.

PubMed

Klettner, Alexa; Kauppinen, Anu; Blasiak, Janusz; Roider, Johan; Salminen, Antero; Kaarniranta, Kai

2013-07-01

Age-related macular degeneration (AMD) is a complex, degenerative and progressive disease involving multiple genetic and environmental factors. It can result in severe visual loss e.g. AMD is the leading cause of blindness in the elderly in the western countries. Although age, genetics, diet, smoking, and many cardiovascular factors are known to be linked with this disease there is increasing evidence that long-term oxidative stress, impaired autophagy clearance and inflammasome mediated inflammation are involved in the pathogenesis. Under certain conditions these may trigger detrimental processes e.g. release of vascular endothelial growth factor (VEGF), causing choroidal neovascularization e.g. in wet AMD. This review ties together these crucial pathological threads in AMD. Copyright © 2013 Elsevier Ltd. All rights reserved.

Molecular dynamics-based model of VEGF-A and its heparin interactions.

PubMed

Uciechowska-Kaczmarzyk, Urszula; Babik, Sándor; Zsila, Ferenc; Bojarski, Krzysztof Kamil; Beke-Somfai, Tamás; Samsonov, Sergey A

2018-06-01

We present a computational model of the Vascular Endothelial Growth Factor (VEGF), an important regulator of blood vessels formation, which function is affected by its heparin interactions. Although structures of a receptor binding (RBD) and a heparin binding domain (HBD) of VEGF are known, there are structural data neither on the 12 amino acids interdomain linker nor on its complexes with heparin. We apply molecular docking and molecular dynamics techniques combined with circular dichroism spectroscopy to model the full structure of the dimeric VEGF and to propose putative molecular mechanisms underlying the function of VEGF/VEGF receptors/heparin system. We show that both the conformational flexibility of the linker and the formation of HBD-heparin-HBD sandwich-like structures regulate the mutual disposition of HBDs and so affect the VEGF-mediated signalling. Copyright © 2018 Elsevier Inc. All rights reserved.

Novel Selective Detection Method of Tumor Angiogenesis Factors Using Living Nano-Robots

PubMed Central

Alshraiedeh, Nida; Owies, Rami; Alshdaifat, Hala; Al-Mahaseneh, Omamah; Al-Tall, Khadijah; Alawneh, Rawan

2017-01-01

This paper reports a novel self-detection method for tumor cells using living nano-robots. These living robots are a nonpathogenic strain of E. coli bacteria equipped with naturally synthesized bio-nano-sensory systems that have an affinity to VEGF, an angiogenic factor overly-expressed by cancer cells. The VEGF-affinity/chemotaxis was assessed using several assays including the capillary chemotaxis assay, chemotaxis assay on soft agar, and chemotaxis assay on solid agar. In addition, a microfluidic device was developed to possibly discover tumor cells through the overexpressed vascular endothelial growth factor (VEGF). Various experiments to study the sensing characteristic of the nano-robots presented a strong response toward the VEGF. Thus, a new paradigm of selective targeting therapies for cancer can be advanced using swimming E. coli as self-navigator miniaturized robots as well as drug-delivery vehicles. PMID:28708066

Mesoporous silicate nanoparticles/3D nanofibrous scaffold-mediated dual-drug delivery for bone tissue engineering.

PubMed

Yao, Qingqing; Liu, Yangxi; Selvaratnam, Balaranjan; Koodali, Ranjit T; Sun, Hongli

2018-04-09

Controlled delivery systems play a critical role in the success of bone morphogenetic proteins (i.e., BMP2 and BMP7) for challenged bone repair. Instead of single-drug release that is currently and commonly prevalent, dual-drug delivery strategies are highly desired to achieve effective bone regeneration because natural bone repair process is driven by multiple factors. Particularly, angiogenesis is essential for osteogenesis and requires more than just one factor (e.g., Vascular Endothelial Growth Factor, VEGF). Therefore, we developed a novel mesoporous silicate nanoparticles (MSNs) incorporated-3D nanofibrous gelatin (GF) scaffold for dual-delivery of BMP2 and deferoxamine (DFO). DFO is a hypoxia-mimetic drug that can activate hypoxia-inducible factor-1 alpha (HIF-1α), and trigger subsequent angiogenesis. Sustained BMP2 release system was achieved through encapsulation into large-pored MSNs, while the relative short-term release of DFO was engineered through covalent conjugation with chitosan to reduce its cytotoxicity and elongate its half-life. Both MSNs and DFO were incorporated onto a porous 3D GF scaffold to serve as a biomimetic osteogenic microenvironment. Our data indicated that DFO and BMP2 were released from a scaffold at different release rates (10 vs 28 days) yet maintained their angiogenic and osteogenic ability, respectively. Importantly, our data indicated that the released DFO significantly improved BMP2-induced osteogenic differentiation where the dose/duration was important for its effects in both mouse and human stem cell models. Thus, we developed a novel and tunable MSNs/GF 3D scaffold-mediated dual-drug delivery system and studied the potential application of the both FDA-approved DFO and BMP2 for bone tissue engineering. Copyright © 2018 Elsevier B.V. All rights reserved.

Both high expression of pyruvate kinase M2 and vascular endothelial growth factor-C predicts poorer prognosis in human breast cancer.

PubMed

Lin, Yang; Liu, Fangfang; Fan, Yu; Qian, Xiaolong; Lang, Ronggang; Gu, Feng; Gu, Jun; Fu, Li

2015-01-01

Pyruvate kinase M2 (PKM2) and vascular endothelial growth factor-C (VEGF-C) have been known to play an important role in tumorigenesis and tumor progression in breast cancer. However, the association between PKM2 and VEGF-C in breast cancer remains unclear. In the present study, a total of 218 specimens from breast cancer patients and 26 paired breast tumors with adjacent normal tissues as well as two breast cancer cell lines were enrolled to investigate the correlation between PKM2 and VEGF-C. We found that PKM2 and VEGF-C mRNA levels were both significantly increasing in breast tumors compared with adjacent normal tissues. Knockdown of PKM2 mRNA expression resulted in VEGF-C mRNA and protein down-regulated as well as cell proliferation inhibited. A positive correlation between PKM2 and VEGF-C expression was identified by immunohistochemical analyses of 218 specimens of patients with breast cancer (P=0.023). PKM2 high expression was significantly correlated with histological grade (P=0.030), lymph node stage (P=0.001), besides VEGF-C high expression was significantly associated with lymphovascular invasion (P=0.012). While combined high expression of PKM2 and VEGF-C was found to be associated with worse histological grade, more lymph node metastasis, more lymphovascular invasion, shorter progression free survival (PFS), and poorer overall survival (OS) in human breast cancer. The results of the present study suggested that PKM2 expression was correlated with VEGF-C expression, and combination of PKM2 and VEGF-C levels had the better prognostic significance in predicting the poor outcome of patients with breast cancer.

Associations of VEGF-C Genetic Polymorphisms with Urothelial Cell Carcinoma Susceptibility Differ between Smokers and Non-Smokers in Taiwan

PubMed Central

Tung, Min-Che; Hsieh, Ming-Ju; Wang, Shian-Shiang; Yang, Shun-Fa; Chen, Shiou-Sheng; Wang, Shih-Wei; Lee, Liang-Ming; Lee, Wei-Jiunn; Chien, Ming-Hsien

2014-01-01

Background Vascular endothelial growth factor (VEGF)-C is associated with lymphangiogenesis, pelvic regional lymph node metastasis, and an antiapoptotic phenotype in urothelial cell carcinoma (UCC). Knowledge of potential roles of VEGF-C genetic polymorphisms in susceptibility to UCC is lacking. This study was designed to examine associations between VEGF-C gene variants and UCC susceptibility and evaluate whether they are modified by smoking. Methodology/Principal Findings Five single-nucleotide polymorphisms (SNPs) of VEGF-C were analyzed by a TaqMan-based real-time polymerase chain reaction (PCR) in 233 patients with UCC and 520 cancer-free controls. A multivariate logistic regression was applied to model associations between genetic polymorphisms and UCC susceptibility, and to determine if the effect was modified by smoking. We found that after adjusting for other covariates, individuals within the entire population and the 476 non-smokers carrying at least one A allele at VEGF-C rs1485766 respectively had 1.742- and 1.834-fold risks of developing UCC than did wild-type (CC) carriers. Among the 277 smokers, we found that VEGF-C rs7664413 T (CT+TT) and rs2046463 G (AG+GG) allelic carriers were more prevalent in UCC patients than in non-cancer participants. Moreover, UCC patients with the smoking habit who had at least one T allele of VEGF-C rs7664413 were at higher risk of developing larger tumor sizes (p = 0.021), compared to those patients with CC homozygotes. Conclusions Our results suggest that the involvement of VEGF-C genotypes in UCC risk differs among smokers compared to non-smokers among Taiwanese. The genetic polymorphism of VEGF-C rs7664413 might be a predictive factor for the tumor size of UCC patients who have a smoking habit. PMID:24608123

Associations of VEGF-C genetic polymorphisms with urothelial cell carcinoma susceptibility differ between smokers and non-smokers in Taiwan.

PubMed

Tung, Min-Che; Hsieh, Ming-Ju; Wang, Shian-Shiang; Yang, Shun-Fa; Chen, Shiou-Sheng; Wang, Shih-Wei; Lee, Liang-Ming; Lee, Wei-Jiunn; Chien, Ming-Hsien

2014-01-01

Vascular endothelial growth factor (VEGF)-C is associated with lymphangiogenesis, pelvic regional lymph node metastasis, and an antiapoptotic phenotype in urothelial cell carcinoma (UCC). Knowledge of potential roles of VEGF-C genetic polymorphisms in susceptibility to UCC is lacking. This study was designed to examine associations between VEGF-C gene variants and UCC susceptibility and evaluate whether they are modified by smoking. Five single-nucleotide polymorphisms (SNPs) of VEGF-C were analyzed by a TaqMan-based real-time polymerase chain reaction (PCR) in 233 patients with UCC and 520 cancer-free controls. A multivariate logistic regression was applied to model associations between genetic polymorphisms and UCC susceptibility, and to determine if the effect was modified by smoking. We found that after adjusting for other covariates, individuals within the entire population and the 476 non-smokers carrying at least one A allele at VEGF-C rs1485766 respectively had 1.742- and 1.834-fold risks of developing UCC than did wild-type (CC) carriers. Among the 277 smokers, we found that VEGF-C rs7664413 T (CT+TT) and rs2046463 G (AG+GG) allelic carriers were more prevalent in UCC patients than in non-cancer participants. Moreover, UCC patients with the smoking habit who had at least one T allele of VEGF-C rs7664413 were at higher risk of developing larger tumor sizes (p = 0.021), compared to those patients with CC homozygotes. Our results suggest that the involvement of VEGF-C genotypes in UCC risk differs among smokers compared to non-smokers among Taiwanese. The genetic polymorphism of VEGF-C rs7664413 might be a predictive factor for the tumor size of UCC patients who have a smoking habit.

Ten-fold augmentation of endothelial uptake of vascular endothelial growth factor with ultrasound after systemic administration

NASA Technical Reports Server (NTRS)

Mukherjee, D.; Wong, J.; Griffin, B.; Ellis, S. G.; Porter, T.; Sen, S.; Thomas, J. D.

2000-01-01

OBJECTIVES: In this study, the feasibility of delivering and enhancing the uptake of vascular endothelial growth factor (VEGF) into the intact endothelium by using ultrasound (US) facilitation was determined. BACKGROUND: A limitation of tissue-targeted drug delivery is the need for direct arterial cannulation. We postulate a mechanism by which agents injected intravenously may be targeted to a tissue using US and ultrasonic contrast agents. METHODS: We used a rat model to test the ability of US and an ultrasonic contrast agent perflurocarbon exposed sonicated dextrose albumin (PESDA) to increase uptake of VEGF in the myocardium. Continuous wave Doppler US (0.6 W/cm2 at 1 MHz for 15 min) was applied to the chest wall overlying the myocardium during intravenous injection with either VEGF (100 microg/kg) alone or a combination of VEGF and PESDA (0.1%). Control rats had VEGF infused without US or PESDA. The VEGF uptake was measured quantitatively in the heart, lung, liver and kidneys by enzyme-linked immunosorbent assay (ng/g of tissue) and morphologically by fluorescence microscopy. RESULTS: There was an eight-fold increase in VEGF uptake in the heart by US alone (16.86 +/- 1.56 vs. 2.11 +/- 0.953 ng/g of tissue, p < 0.0001) and a 13-fold increase with US + PESDA (26.78 +/- 2.88 vs. 2.11 +/- 0.953 ng/g of tissue, p < 0.0001) compared with control rats. Fluorescence microscopy revealed deposition of VEGF in the endothelium of small intramyocardial arterioles. CONCLUSIONS: These results show a marked increase in endothelial VEGF uptake with US and US + PESDA. Thus, US may be used to augment endothelial VEGF uptake 10-fold to 13-fold.

Inhibitory Effect of Vascular Endothelial Growth Factor on the Slowly Activating Delayed Rectifier Potassium Current in Guinea Pig Ventricular Myocytes.

PubMed

Lin, Zhenhao; Xing, Wenlu; Gao, Chuanyu; Wang, Xianpei; Qi, Datun; Dai, Guoyou; Zhao, Wen; Yan, Ganxin

2018-01-26

Vascular endothelial growth factor (VEGF) exerts a number of beneficial effects on ischemic myocardium via its angiogenic properties. However, little is known about whether VEGF has a direct effect on the electrical properties of cardiomyocytes. In the present study, we investigated the effects of different concentrations of VEGF on delayed rectifier potassium currents (I K ) in guinea pig ventricular myocytes and their effects on action potential (AP) parameters. I K and AP were recorded by the whole-cell patch clamp method in ventricular myocytes. Cells were superfused with control solution or solution containing VEGF at different concentrations for 10 minutes before recording. Some ventricular myocytes were pretreated with a phosphatidylinositol 3-kinase inhibitor for 1 hour before the addition of VEGF. We found that VEGF inhibited the slowly activating delayed rectifier potassium current (I K s ) in a concentration-dependent manner (18.13±1.04 versus 12.73±0.34, n=5, P =0.001; 12.73±0.34 versus 9.05±1.20, n=5, P =0.036) and prolonged AP duration (894.5±36.92 versus 746.3±33.71, n=5, P =0.021). Wortmannin, a phosphatidylinositol 3-kinase inhibitor, eliminated these VEGF-induced effects. VEGF had no significant effect on the rapidly activating delayed rectifier potassium current (I K r ), resting membrane potential, AP amplitude, or maximal velocity of depolarization. VEGF inhibited I K s in a concentration-dependent manner through a phosphatidylinositol 3-kinase-mediated signaling pathway, leading to AP prolongation. The results indicate a promising therapeutic potential of VEGF in prevention of ventricular tachyarrhythmias under conditions of high sympathetic activity and ischemia. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Role of Endocrine Gland-Derived Vascular Endothelial Growth Factor (EG-VEGF) and Its Receptors in Adrenocortical Tumors.

PubMed

Heck, Dorothee; Wortmann, Sebastian; Kraus, Luitgard; Ronchi, Cristina L; Sinnott, Richard O; Fassnacht, Martin; Sbiera, Silviu

2015-12-01

Angiogenesis is essential for tumor growth and metastasis. Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an angiogenic factor predominantly expressed in steroidogenic organs like the adrenal gland, ovary, testes, and placenta. EG-VEGF has antiapoptotic, mitogenic, and chemoattractive properties mediated via the two G protein-coupled receptors prokineticin receptor 1 (PKR1) and prokineticin receptor 2 (PKR2). We investigated the expression of EG-VEGF and its receptors in a large number of normal adrenal glands (NAG), adrenocortical adenomas (ACA), and carcinomas (ACC) using real-time PCR (NAG, n = 12; ACA, n = 24; and ACC, n = 30) and immunohistochemistry (NAG, n = 9; ACA, n = 23; and ACC, n = 163) and evaluated its impact on patients' survival. EG-VEGF, PKR1, and PKR2 mRNA and protein are expressed in NAG and the vast majority of ACA and ACC samples. The mean EG-VEGF mRNA expression was significantly lower in ACC (606.5 ± 77.1 copies) compared to NAG (4,043 ± 1,111) and cortisol-producing adenomas (CPA) (4,433 ± 2,378) (p < 0.01 and p < 0.05, respectively). However, cytoplasmic and nuclear EG-VEGF protein expression was either significantly higher or similar in ACC (H score 2.4 ± 0.05, p < 0.05 and 1.7 ± 0.08, n.s., respectively) compared to NAG (1.8 ± 0.14 and 1.7 ± 0.2). Nuclear protein expression of either EG-VEGF or PKR1 or both is predictive for a higher mortality compared to patients without nuclear expression (hazard ratio (HR) = 5.15; 95% confidence interval (CI) = 1.24-21.36, n = 100, p = 0.02 independent of age, sex, and tumor stage). These findings suggest that EG-VEGF and its receptor PKR1 might play a role in the pathogenesis of adrenocortical tumors and could serve as prognostic markers for this rare malignant disease.

Resistive-Pulse Measurements with Nanopipettes: Detection of Vascular Endothelial Growth Factor C (VEGF-C) Using Antibody-Decorated Nanoparticles.

PubMed

Cai, Huijing; Wang, Yixian; Yu, Yun; Mirkin, Michael V; Bhakta, Snehasis; Bishop, Gregory W; Joshi, Amit A; Rusling, James F

2015-06-16

Quartz nanopipettes have recently been employed for resistive-pulse sensing of Au nanoparticles (AuNP) and nanoparticles with bound antibodies. The analytical signal in such experiments is the change in ionic current caused by the nanoparticle translocation through the pipette orifice. This paper describes resistive-pulse detection of cancer biomarker (Vascular Endothelial Growth Factor-C, VEGF-C) through the use of antibody-modified AuNPs and nanopipettes. The main challenge was to differentiate between AuNPs with attached antibodies for VEGF-C and antigen-conjugated particles. The zeta-potentials of these types of particles are not very different, and, therefore, carefully chosen pipettes with well-characterized geometry were necessary for selective detection of VEGF-C.

Resistive-Pulse Measurements with Nanopipettes: Detection of Vascular Endothelial Growth Factor C (VEGF-C) Using Antibody-Decorated Nanoparticles

PubMed Central

Cai, Huijing; Wang, Yixian; Yu, Yun; Mirkin, Michael V.; Bhakta, Snehasis; Bishop, Gregory W.; Joshi, Amit A.; Rusling, James F.

2015-01-01

Quartz nanopipettes have recently been employed for resistive-pulse sensing of Au nanoparticles (AuNP) and nanoparticles with bound antibodies. The analytical signal in such experiments is the change in ionic current caused by the nanoparticle translocation through the pipette orifice. This paper describes resistive-pulse detection of cancer biomarker (Vascular Endothelial Growth Factor-C, VEGF-C) through the use of antibody-modified AuNPs and nanopipettes. The main challenge was to differentiate between AuNPs with attached antibodies for VEGF-C and antigen-conjugated particles. The zeta-potentials of these types of particles are not very different, and, therefore, carefully chosen pipettes with well-characterized geometry were necessary for selective detection of VEGF-C. PMID:26040997

Constructing a blood vessel on the porous scaffold modified with vascular endothelial growth factor and basic fibroblast growth factor

NASA Astrophysics Data System (ADS)

Sevostyanova, V. V.; Matveeva, V. G.; Antonova, L. V.; Velikanova, E. A.; Shabaev, A. R.; Senokosova, E. A.; Krivkina, E. O.; Vasyukov, G. Yu.; Glushkova, T. V.; Kudryavtseva, Yu. A.; Barbarash, O. L.; Barbarash, L. S.

2016-11-01

Incorporation of the growth factors into biodegradable polymers is a promising approach for the fabrication of tissue-engineered vascular grafts. Here we blended poly(ɛ-caprolactone) (PCL) with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) following incorporation of either vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) and then fabricated electrospun 2 mm diameter vascular grafts. Grafts without the growth factors were used as a control group. Structure of the grafts was assessed utilizing scanning electron microscopy. We further implanted our grafts into rat abdominal aorta for 1 and 3 months with the aim to test endothelialization, cell infiltration, and patency in vivo. Histological and immunofluorescence examination demonstrated enhanced endothelialization and cell infiltration of the grafts with either VEGF or bFGF compared to those without the growth factors. Grafts with VEGF showed higher patency compared to those with bFGF; however, bFGF promoted migration of smooth muscle cells and fibroblasts into the graft. Therefore, we conclude that incorporation of VEGF and bFGF into the inner and medial/outer layer, respectively, can be a promising option for the fabrication of tissue-engineered vascular grafts.

VEGF-C and VEGF-D blockade inhibits inflammatory skin carcinogenesis.

PubMed

Alitalo, Annamari K; Proulx, Steven T; Karaman, Sinem; Aebischer, David; Martino, Stefania; Jost, Manuela; Schneider, Nicole; Bry, Maija; Detmar, Michael

2013-07-15

VEGF-C and VEGF-D were identified as lymphangiogenic growth factors and later shown to promote tumor metastasis, but their effects on carcinogenesis are poorly understood. Here, we have studied the effects of VEGF-C and VEGF-D on tumor development in the murine multistep chemical carcinogenesis model of squamous cell carcinoma by using a soluble VEGF-C/VEGF-D inhibitor. After topical treatment with a tumor initiator and repeated tumor promoter applications, transgenic mice expressing a soluble VEGF-C/VEGF-D receptor (sVEGFR-3) in the skin developed significantly fewer squamous cell tumors with a delayed onset when compared with wild-type mice or mice expressing sVEGFR-3 lacking the ligand-binding site. Epidermal proliferation was reduced in the carcinogen-treated transgenic skin, whereas epidermal keratinocyte proliferation in vitro was not affected by VEGF-C or VEGF-D, indicating indirect effects of sVEGFR-3 expression. Importantly, transgenic mouse skin was less sensitive to tumor promoter-induced inflammation, with reduced angiogenesis and blood vessel leakage. Cutaneous leukocytes, especially macrophages, were reduced in transgenic skin without major changes in macrophage polarization or blood monocyte numbers. Several macrophage-associated cytokines were also reduced in transgenic papillomas, although the dermal macrophages themselves did not express VEGFR-3. These findings indicate that VEGF-C/VEGF-D are involved in shaping the inflammatory tumor microenvironment that regulates early tumor progression. Our results support the use of VEGF-C/VEGF-D-blocking agents not only to inhibit metastatic progression, but also during the early stages of tumor growth. ©2013 AACR.

The effect of platelet rich fibrin on growth factor levels in urethral repair.

PubMed

Soyer, Tutku; Ayva, Şebnem; Boybeyi, Özlem; Aslan, Mustafa Kemal; Çakmak, Murat

2013-12-01

Platelet rich fibrin (PRF) is an autologous source of growth factors and promotes wound healing. An experimental study was performed to evaluate the effect of PRF on growth factor levels in urethral repair. Eighteen Wistar albino rats were included in the study. Rats were allocated in three groups (n:6): control (CG), sham (SG), and PRF (PRFG). In SG, a 5 mm vertical incision was performed in the penile urethra and repaired with 10/0 Vicryl® under a microscope. In PRFG, during the urethral repair as described in SG, 1 cc of blood was sampled from each rat and centrifuged for 10 minutes at 2400 rpm. PRF obtained from the centrifugation was placed on the repair site during closure. Penile urethras were sampled 24 hours after PRF application in PRFG and after urethral repair in SG. Transforming growth factor beta receptor (TGF-β-R-CD105), vascular endothelial growth factor (VEGF) and its receptor (VEGF-R), as well as endothelial growth factor receptor (EGFR), were evaluated in subepithelia of the penile skin and urethra. Groups were compared for growth factor levels and growth factor receptor expression with the Kruskal Wallis test. TGF-β-R levels were significantly decreased in SG when compared to CG (p<0.05). In PRFG, TGF-β-R was increased in both subepithelia of penile skin and urethra with respect to SG (p<0.05). When VEGF levels and its receptor expression were compared between SG and PRFG, VEGF levels were found to be increased in penile skin subepithelium, whereas VEGF-R expressions were decreased in urethral subepithelia in PRFG (p<0.05). There was no difference between groups for EGFR levels (p>0.05). Use of PRF after urethral repair increases TGF-β-R and VEGF expressions in urethral tissue. PRF can be considered as an alternative measure to improve the success of urethral repair. © 2013.

[Antitumor effect of recombinant T7 phage vaccine expressing xenogenic vascular endothelial growth factor on Lewis lung cancer in mice].

PubMed

Li, Xiao-Hui; Tang, Liang; Liu, Dong; Sun, Hong-Mei; Zhou, Cai-Cun; Tan, Li-Song; Wang, Li-Ping; Zhang, Pei-De; Zhang, Shang-Quan

2006-10-01

Angiogenesis plays an important role in growth and metastasis of tumors. Vascular endothelial growth factor (VEGF) is considered as a fundamental regulator for angiogenesis. This study was to construct a recombinant T7 phage vaccine expressing xenogenic VEGF on the capsid, and test its inhibitory effect on Lewis lung cancer cells in mice. VEGF gene was cloned by reverse transcription-polymerase chain reaction (RT-PCR) from human lung cancer tissues, and inserted into phage using T7 Select10-3b kit to construct T7 Select10-3b_VEGF vaccine. The titer of prepared phage reached 1x10(13) pfu/ml. C57BL/6J mice were randomly divided into 3 groups: T7 Select10-3b_VEGF vaccine group (T7-VEGF), T7 phage (T7) group, normal saline (NS) group (10 mice/group). Each mouse was injected with Freundos adjuvant mixed with 1x10(12) pfu/200 microl T7 Select10-3b_VEGF, or T7, or normal saline once a week for 4 weeks. Lewis lung carcinoma model (LL/2) was established in C57BL/6J mice after 4-week immunization. Tumor growth and mouse's physical status were observed during immunization. Tumor weight and serum level of specific anti-VEGF antibody were measured by enzyme-linked immunosorbent assay (ELISA). Microvessel density (MVD) of tumors was detected by immunohistochemistry 14 days after the inoculation of tumor cells. Tumor weight of T7-VEGF vaccine group,T7 group, and NS group were (0.543+/-0.259)g, (0.982+/-0.359)g, (1.169+/-0.460)g, respectively. Tumor weight of T7-VEGF vaccine group was significantly lower than that of NS group (P<0.01). Serum anti-VEGF antibody level in T7-VEGF vaccine group was 1:1,000. MVD was significantly lower in T7-VEGF vaccine group than in NS group (8.5+/-0.8 vs 18.5+/-1.6, P<0.05). MVD in T7 group was 16.4+/-1.3. Recombinant T7 phage vaccine expressing xenogenic VEGF can break immunologic tolerance against self-VEGF and inhibit the growth of Lewis lung cancer cells.

A case of angioimmunoblastic T-cell lymphoma with high serum VEGF preceded by RS3PE syndrome.

PubMed

Tabeya, Tetsuya; Sugaya, Toshiaki; Suzuki, Chisako; Yamamoto, Motohisa; Kanaseki, Takayuki; Noguchi, Hiroko; Naishiro, Yasuyoshi; Ishida, Tadao; Takahashi, Hiroki; Shinomura, Yasuhisa

2016-01-01

We report the case of a 76-year-old man diagnosed with angioimmunoblastic T-cell lymphoma (AITL) with high serum vascular endothelial growth factor (VEGF) preceded by Remitting seronegative symmetrical synovitis with pitting edema syndrome. He suffered respiratory discomfort caused by large amounts of pleural effusion. Interestingly, changes in serum VEGF measured over time were similar to changes in pleural effusion. Whether VEGF is related to the pathological condition of AITL is a very important question.

Evaluation of serum and pleural levels of endostatin and vascular epithelial growth factor in lung cancer patients with pleural effusion.

PubMed

Zhang, Yu; Yu, Li-Ke; Xia, Ning

2012-03-01

To evaluate the diagnostic value of endostatin (ES), vascular endothelial growth factor (VEGF) and carcinoembryonic antigen (CEA) in both serum and pleural effusion of lung cancer patients. Levels of ES, VEGF and CEA in 52 malignant pleural effusion due to lung cancer and 50 patients with non-malignant disease were measured by using sandwich enzyme-linked immunosorbent assay and microparticle enzyme immunoassay. The ES, VEGF and CEA levels in pleural effusion and serum, and their ratio (F/S) were higher in lung cancer group than that in benign group, and the differences were statistically significant (P<0.05). The diagnostic efficiency of ES+VEGF for lung cancer was superior to either single detection. The diagnostic efficiency of ES+VEGF+CEA was superior to either ES+VEGF or ES+CEA. The results suggest that ES, VEGF and CEA might be useful in the differentiation between benign and malignant pleural effusion due to lung cancer. In comparison with either single determination of concentration in serum or pleural fluid, the combined detection of two or three markers is of important clinical significance in the diagnosis of lung cancer. Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Angiomodulin is a specific marker of vasculature and regulates VEGF-A dependent neo-angiogenesis

PubMed Central

Hooper, Andrea T.; Shmelkov, Sergey V.; Gupta, Sunny; Milde, Till; Bambino, Kathryn; Gillen, Kelly; Goetz, Mollie; Chavala, Sai; Baljevic, Muhamed; Murphy, Andrew J.; Valenzuela, David M.; Gale, Nicholas W.; Thurston, Gavin; Yancopoulos, George D.; Vahdat, Linda; Evans, Todd; Rafii, Shahin

2010-01-01

Blood vessel formation is controlled by the balance between pro- and anti-angiogenic pathways. Although much is known about the factors that drive sprouting of neovessels, the factors that stabilize and pattern neovessels are undefined. The expression of angiomodulin (AGM), a VEGF-A binding protein, was increased in the vasculature of several human tumors as compared to normal tissue, raising the hypothesis that AGM may modulate VEGF-A-dependent vascular patterning. To elucidate the expression pattern of AGM, we developed an AGM knockin reporter mouse (AGMlacZ/+) wherein we demonstrate that AGM is predominantly expressed in the vasculature of developing embryos and adult organs. During physiological and pathological angiogenesis, AGM is upregulated in the angiogenic vasculature. Using the zebrafish model, we found that AGM is restricted to developing vasculature by 17-22 hpf. Blockade of AGM activity with morpholino oligomers (MO) results in prominent angiogenesis defects in vascular sprouting and remodeling. Concurrent knockdown of both AGM and VEGF-A results in synergistic angiogenesis defects. When VEGF-A is overexpressed, the compensatory induction of the VEGF-A receptor, VEGFR-2/flk-1, is blocked by the simultaneous injection of AGM MO. These results demonstrate that the vascular-specific marker AGM modulates vascular remodeling in part by temporizing the pro-angiogenic effects of VEGF-A. PMID:19542015

An anti-VEGF ribozyme embedded within the adenoviral VAI sequence inhibits glioblastoma cell angiogenic potential in vitro.

PubMed

Ciafrè, Silvia Anna; Niola, Francesco; Wannenes, Francesca; Farace, Maria Giulia

2004-01-01

Vascular endothelial growth factor (VEGF) plays an important role in tumor angiogenesis, where it functions as one of the major angiogenic factors sustaining growth and draining catabolites. In this study, we developed an anti-VEGF ribozyme targeted to the 5' part of human VEGF mRNA. We endowed this ribozyme with an additional feature expected to improve its activity in vivo, by cloning it into a VAI transcriptional cassette. VAI is originally part of the adenovirus genome, and is characterized by high transcription rates, good stability due to its strong secondary structure and cytoplasmic localization. Transfection of U87 human glioblastoma cells with plasmid vectors encoding for this ribozyme resulted in a strong (-56%) reduction of VEGF secreted in the extracellular medium, indicating a good biological activity of the ribozyme. Moreover, this reduction in VEGF secretion had the important functional consequence of drastically diminishing the formation of tube-like structures of human umbilical vascular endothelial cells in a Matrigel in vitro angiogenesis assay. In conclusion, our VAI-embedded anti-VEGF ribozyme is a good inhibitor of angiogenesis in vitro, in a glioblastoma cell context. Thus, it may represent a useful tool for future applications in vivo, for antiangiogenic gene therapy of glioblastoma and of highly vascularized tumors. Copyright 2004 S. Karger AG, Basel

Angiogenin and vascular endothelial growth factor expression in lungs of lung cancer patients.

PubMed

Rozman, Ales; Silar, Mira; Kosnik, Mitja

2012-12-01

BACKGROUND.: Lung cancer is the leading cause of cancer deaths. Angiogenesis is crucial process in cancer growth and progression. This prospective study evaluated expression of two central regulatory molecules: angiogenin and vascular endothelial growth factor (VEGF) in patients with lung cancer. PATIENTS AND METHODS.: Clinical data, blood samples and broncho-alveolar lavage (BAL) from 23 patients with primary lung carcinoma were collected. BAL fluid was taken from part of the lung with malignancy, and from corresponding healthy side of the lung. VEGF and angiogenin concentrations were analysed by an enzyme-linked immunosorbent assay. Dilution of bronchial secretions in the BAL fluid was calculated from urea concentration ratio between serum and BAL fluid. RESULTS.: We found no statistical correlation between angiogenin concentrations in serum and in bronchial secretions from both parts of the lung. VEGF concentrations were greater in bronchial secretions in the affected side of the lung than on healthy side. Both concentrations were greater than serum VEGF concentration. VEGF concentration in serum was in positive correlation with tumour size (p = 0,003) and with metastatic stage of disease (p = 0,041). There was correlation between VEGF and angiogenin concentrations in bronchial secretions from healthy side of the lung and between VEGF and angiogenin concentrations in bronchial secretions from part of the lung with malignancy. CONCLUSION.: Angiogenin and VEGF concentrations in systemic, background and local samples of patients with lung cancer are affected by different mechanisms. Pro-angiogenic activity of lung cancer has an important influence on the levels of angiogenin and VEGF.

Angiogenin and vascular endothelial growth factor expression in lungs of lung cancer patients

PubMed Central

Rozman, Ales; Silar, Mira; Kosnik, Mitja

2012-01-01

Background. Lung cancer is the leading cause of cancer deaths. Angiogenesis is crucial process in cancer growth and progression. This prospective study evaluated expression of two central regulatory molecules: angiogenin and vascular endothelial growth factor (VEGF) in patients with lung cancer. Patients and methods. Clinical data, blood samples and broncho-alveolar lavage (BAL) from 23 patients with primary lung carcinoma were collected. BAL fluid was taken from part of the lung with malignancy, and from corresponding healthy side of the lung. VEGF and angiogenin concentrations were analysed by an enzyme-linked immunosorbent assay. Dilution of bronchial secretions in the BAL fluid was calculated from urea concentration ratio between serum and BAL fluid. Results. We found no statistical correlation between angiogenin concentrations in serum and in bronchial secretions from both parts of the lung. VEGF concentrations were greater in bronchial secretions in the affected side of the lung than on healthy side. Both concentrations were greater than serum VEGF concentration. VEGF concentration in serum was in positive correlation with tumour size (p = 0,003) and with metastatic stage of disease (p = 0,041). There was correlation between VEGF and angiogenin concentrations in bronchial secretions from healthy side of the lung and between VEGF and angiogenin concentrations in bronchial secretions from part of the lung with malignancy. Conclusion. Angiogenin and VEGF concentrations in systemic, background and local samples of patients with lung cancer are affected by different mechanisms. Pro-angiogenic activity of lung cancer has an important influence on the levels of angiogenin and VEGF. PMID:23412843

Ethnic differences in the +405 and -460 vascular endothelial growth factor polymorphisms and peripheral neuropathy in patients with diabetes residing in a North London, community in the United Kingdom.

PubMed

Zitouni, Karima; Tinworth, Lorna; Earle, Kenneth Anthony

2017-06-29

There are marked ethnic differences in the susceptibility to the long-term diabetic vascular complications including sensory neuropathy. The vascular endothelial growth factor (VEGF) +405 (C/G) and -460 (T/C) polymorphisms are associated with retinopathy and possibly with nephropathy, however no information is available on their relationship with peripheral neuropathy. Therefore, we examined the prevalence of these VEGF genotypes in a multi-ethnic cohort of patients with diabetes and their relationship with evident peripheral diabetic neuropathy. In the current investigation, we studied 313 patients with diabetes mellitus of African-Caribbean, Indo-Asian and Caucasian ethnic origin residing in an inner-city community in London, United Kingdom attending a single secondary care centre. Genotyping was performed for the VEGF +405 and VEGF -460 polymorphisms using a pyrosequencing technique. Forty-nine patients (15.6%) had clinical evidence of peripheral neuropathy. Compared to Caucasian patients, African-Caribbean and Indo-Asian patients had lower incidence of neuropathy (24.6%, 14.28%, 6.7%, respectively; P = 0.04). The frequency of the VEGF +405 GG genotype was more common in Indo-Asian patients compared to African-Caribbean and Caucasian patients (67.5%, 45.3%, 38.4%, respectively; p ≤ 0.02). The G allele was more common in patients with type 2 diabetes of Indo-Asian origin compared to African-Caribbean and Caucasian origin (p ≤ 0.02). There was no difference between the ethnic groups in VEGF -460 genotypes. The distributions of the VEGF +405 and VEGF -460 genotypes were similar between the diabetic patients with and without neuropathy. In this cohort of patients, VEGF +405 and VEGF -460 polymorphisms were not associated with evident diabetic peripheral neuropathy, however an association was found between VEGF +405 genotypes and Indo-Asian which might have relevance to their lower rates of ulceration and amputation. This finding highlights the need for further investigation of any possible relationship between VEGF genotype, circulating VEGF concentrations and differential vulnerability to peripheral neuropathy amongst diabetic patients of different ethnic backgrounds.

The effects of RNA interference mediated VEGF gene silencing on biological behavior of renal cell carcinoma and transplanted renal tumor in nude mice.

PubMed

Wang, Qi; Wang, Shuai; Sun, Si-Qiao; Cheng, Zhi-Hua; Zhang, Yang; Chen, Guang; Gu, Meng; Yao, Hai-Jun; Wang, Zhong; Zhou, Juan; Peng, Yu-Bing; Xu, Ming-Xi; Zhang, Ke; Sun, Xi-Wei

2016-01-01

This study was to explore the effects of RNA interference mediated vascular endothelial growth factor (VEGF) gene silencing on biological behavior of renal cell carcinoma (RCC), transplanted renal tumor and angiogenesis in nude mice. The specific siRNA sequence targeting VEGF were designed and synthesized to construct hVEGF-siRNA plasmid which was transfected into RCC 786-O cells. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for the detection of VEGF gene expression and western blot was adopted for the examination of VEGF protein expression. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect cell growth as well as cell migration and invasion. The transplanted renal tumor models in nude mice were established, and the growth condition of nude mice, and VEGF protein expression in transplanted tumor slices and the microvessel density (MVD) were detected. The expression level of VEGF mRNA in VEGF-siRNA group was significant lower than that in the control group and negative group, suggesting that establishment of plasmid specifically inhibited the expression of VEGF gene The expression level of VEGF protein in VEGF-siRNA group was significant lower than that in the control group and negative group. VEGF gene silencing has the significant inhibition effects on proliferation, migration and invasion of RCC 786-O cells. The tumor weight, VEGF protein positive rate and MVD in VEGF-siRNA group were significant lower than those in negative group and blank group. The VEGF gene silencing could inhibit the cell proliferation, migration and invasion of RCC 786-O cells; inhibition of VEGF protein expression could prevent transplanted RCC growth and tumor angiogenesis.

[Effect of vascular endothelial growth factor and tumor necrosis factor receptor for treatment of avascular necrosis of the femoral head in rabbits].

PubMed

Hu, Zhi-ming; Zhou, Ming-qian; Gao, Ji-min

2008-12-01

To evaluate the therapeutic effect of vascular endothelial growth factor (VEGF) and tumor necrosis factor receptor (TNFR) on avascular necrosis of the femoral head in rabbits. Avascular necrosis of the femoral head was induced in 26 New Zealand white rabbits by injections of horse serum and prednisolone. The rabbits were then divided into VEGF/TNFR treatment group, VEGF treatment group, and untreated model group, with another 4 normal rabbits as the normal control group. In the two treatment groups, the therapeutic agents were injected percutaneously into the femoral head. Enzyme-linked immunosorbent assay was performed to determine the concentration of TNF-alpha in rabbit serum followed by pathological examination of the changes in the bone tissues, bone marrow hematopoietic tissue and the blood vessels in the femoral head. Compared with the model group, the rabbits with both VEGF and TNFR treatment showed decreased serum concentration of TNF-alpha with obvious new vessel formation, decreased empty bone lacunae in the femoral head and hematopoietic tissue proliferation in the bone marrow cavity. Percutaneous injection of VEGF and TNFR into the femoral head can significantly enhance bone tissue angiogenesis and ameliorate osteonecrosis in rabbits with experimental femoral head necrosis.

ACCRETA COMPLICATING COMPLETE PLACENTA PREVIA IS CHARACTERIZED BY REDUCED SYSTEMIC LEVELS OF VASCULAR ENDOTHELIAL GROWTH FACTOR AND EPITHELIAL-TO-MESENCHYMAL TRANSITION OF THE INVASIVE TROPHOBLAST

PubMed Central

Wehrum, Mark J.; Buhimschi, Irina A.; Salafia, Carolyn; Thung, Stephen; Bahtiyar, Mert O.; Werner, Erica F.; Campbell, Katherine H.; Laky, Christine; Sfakianaki, Anna K.; Zhao, Guomao; Funai, Edmund F.; Buhimschi, Catalin S.

2011-01-01

OBJECTIVE To characterize serum angiogenic factor profile of women with complete placenta previa and determine if invasive trophoblast differentiation characteristic of accreta, increta or percreta shares features of epitehelial-mesenchymal-transition (EMT). STUDY DESIGN We analyzed gestational age matched serum samples from 90 pregnant women with either complete placenta previa (n=45) or uncomplicated pregnancies (n=45). Vascular-endothelial-growth-factor (VEGF), placental-growth-factor (PlGF) and soluble fms-like-tyrosine-kinase-1 (sFlt-1) were immunoassayed. VEGF and phosphotyrosine (P-Tyr) immunoreactivity was surveyed in histological specimens relative to expression of vimentin and cytokeratin-7. RESULTS Women with previa and invasive placentation [accreta (n=5); increta (n=6); percreta (n=2)] had lower systemic VEGF (invasive previa: median [IQR]: 0.8[0.02–3.4] vs. control: 6.5[2.7–10.5] pg/mL, P=0.02). VEGF and P-Tyr immunostaining predominated in the invasive extravillous trophoblasts (EVT) which co-expressed vimentin and cytokeratin-7, a EMT feature and tumor-like cell phenotype. CONCLUSIONS Lower systemic free VEGF and a switch of the interstitial EVT to a metastable cell phenotype characterize placenta previa with excessive myometrial invasion. PMID:21316642

Prognostic Relevance of the Expression of CA IX, GLUT-1, and VEGF in Ovarian Epithelial Cancers

PubMed Central

Kim, Kyungbin; Park, Won Young; Kim, Jee Yeon; Sol, Mee Young; Shin, Dong Hun; Park, Do Youn; Lee, Chang Hun; Lee, Jeong Hee

2012-01-01

Background Tumor hypoxia is associated with malignant progression and treatment resistance. Hypoxia-related factors, such as carbonic anhydrase IX (CA IX), glucose transporter-1 (GLUT-1), and vascular endothelial growth factor (VEGF) permit tumor cell adaptation to hypoxia. We attempted to elucidate the correlation of these markers with variable clinicopathological factors and overall prognosis. Methods Immunohistochemistry for CA IX, GLUT-1, and VEGF was performed on formalin-fixed, paraffin-embedded tissues from 125 cases of ovarian epithelial cancer (OEC). Results CA IX expression was significantly associated with an endometrioid and mucinous histology, nuclear grade, tumor necrosis, and mitosis. GLUT-1 expression was associated with tumor necrosis and mitosis. VEGF expression was correlated only with disease recurrence. Expression of each marker was not significant in terms of overall survival in OECs; however, there was a significant correlation between poor overall survival rate and high coexpression of these markers. Conclusions The present study suggests that it is questionable whether CA IX, GLUT-1, or VEGF can be used alone as independent prognostic factors in OECs. Using at least two markers helps to predict patient outcomes in total OECs. Moreover, the inhibition of two target gene combinations might prove to be a novel anticancer therapy. PMID:23323103

Anti-Angiogenics: Current Situation and Future Perspectives.

PubMed

Zirlik, Katja; Duyster, Justus

2018-01-01

Angiogenesis, the process leading to the formation of new blood vessels, is one of the hallmarks of cancer. Extensive studies established that i) vascular endothelial growth factor (VEGF) is a key driver of sprouting angiogenesis, ii) VEGF is overexpressed in most solid cancers, and iii) inhibition of VEGF can suppress tumor growth in animal models. This has led to the development of pharmacological agents for anti-angiogenesis to disrupt the vascular supply and starve the tumor of nutrients and oxygen, primarily through the blockade of VEGF/VEGF receptor signaling. This effort has resulted in 11 anti-VEGF drugs approved for certain advanced cancers, either alone or in combination with chemotherapy and other targeted therapies. However, inhibition of VEGF signaling is not effective in all cancers, and anti-angiogenics have often only limited impact on overall survival of cancer patients. This review focuses on the current status of FDA-approved anti-angiogenic antibodies and tyrosine kinase inhibitors and summarizes the progress and future directions of VEGF-targeted therapy. © 2018 S. Karger GmbH, Freiburg.

Dynamics of VEGF matrix-retention in vascular network patterning

NASA Astrophysics Data System (ADS)

Köhn-Luque, A.; de Back, W.; Yamaguchi, Y.; Yoshimura, K.; Herrero, M. A.; Miura, T.

2013-12-01

Vascular endothelial growth factor (VEGF) is a central regulator of blood vessel morphogenesis, although its role in patterning of endothelial cells into vascular networks is not fully understood. It has been suggested that binding of soluble VEGF to extracellular matrix components causes spatially restricted cues that guide endothelial cells into network patterns. Yet, current evidence for such a mechanism remains indirect. In this study, we quantitatively analyse the dynamics of VEGF retention in a controlled in vitro situation of human umbilical vascular endothelial cells (HUVECs) in Matrigel. We show that fluorescent VEGF accumulates in pericellular areas and colocalizes with VEGF binding molecules. Analysis of fluorescence recovery after photobleaching reveals that binding/unbinding to matrix molecules dominates VEGF dynamics in the pericellular region. Computational simulations using our experimental measurements of kinetic parameters show that matrix retention of chemotactic signals can lead to the formation of reticular cellular networks on a realistic timescale. Taken together, these results show that VEGF binds to matrix molecules in proximity of HUVECs in Matrigel, and suggest that bound VEGF drives vascular network patterning.

Calcium alginate gels as stem cell matrix-making paracrine stem cell activity available for enhanced healing after surgery.

PubMed

Schmitt, Andreas; Rödel, Philipp; Anamur, Cihad; Seeliger, Claudine; Imhoff, Andreas B; Herbst, Elmar; Vogt, Stephan; van Griensven, Martijn; Winter, Gerhard; Engert, Julia

2015-01-01

Regeneration after surgery can be improved by the administration of anabolic growth factors. However, to locally maintain these factors at the site of regeneration is problematic. The aim of this study was to develop a matrix system containing human mesenchymal stem cells (MSCs) which can be applied to the surgical site and allows the secretion of endogenous healing factors from the cells. Calcium alginate gels were prepared by a combination of internal and external gelation. The gelling behaviour, mechanical stability, surface adhesive properties and injectability of the gels were investigated. The permeability of the gels for growth factors was analysed using bovine serum albumin and lysozyme as model proteins. Human MSCs were isolated, cultivated and seeded into the alginate gels. Cell viability was determined by AlamarBlue assay and fluorescence microscopy. The release of human VEGF and bFGF from the cells was determined using an enzyme-linked immunoassay. Gels with sufficient mechanical properties were prepared which remained injectable through a syringe and solidified in a sufficient time frame after application. Surface adhesion was improved by the addition of polyethylene glycol 300,000 and hyaluronic acid. Humans MSCs remained viable for the duration of 6 weeks within the gels. Human VEGF and bFGF was found in quantifiable concentrations in cell culture supernatants of gels loaded with MSCs and incubated for a period of 6 weeks. This work shows that calcium alginate gels can function as immobilization matrices for human MSCs.

Discontinuation of anti-VEGF cancer therapy promotes metastasis through a liver revascularization mechanism

PubMed Central

Yang, Yunlong; Zhang, Yin; Iwamoto, Hideki; Hosaka, Kayoko; Seki, Takahiro; Andersson, Patrik; Lim, Sharon; Fischer, Carina; Nakamura, Masaki; Abe, Mitsuhiko; Cao, Renhai; Skov, Peter Vilhelm; Chen, Fang; Chen, Xiaoyun; Lu, Yongtian; Nie, Guohui; Cao, Yihai

2016-01-01

The impact of discontinuation of anti-VEGF cancer therapy in promoting cancer metastasis is unknown. Here we show discontinuation of anti-VEGF treatment creates a time-window of profound structural changes of liver sinusoidal vasculatures, exhibiting hyper-permeability and enlarged open-pore sizes of the fenestrated endothelium and loss of VE-cadherin. The drug cessation caused highly leaky hepatic vasculatures permit tumour cell intravasation and extravasation. Discontinuation of an anti-VEGF antibody-based drug and sunitinib markedly promotes liver metastasis. Mechanistically, host hepatocyte, but not tumour cell-derived vascular endothelial growth factor (VEGF), is responsible for cancer metastasis. Deletion of hepatocyte VEGF markedly ablates the ‘off-drug'-induced metastasis. These findings provide mechanistic insights on anti-VEGF cessation-induced metastasis and raise a new challenge for uninterrupted and sustained antiangiogenic therapy for treatment of human cancers. PMID:27580750

[Relationship between the expression levels of PAPP-A metalloproteinase and growth and transcriptional factors in endometrial cancer].

PubMed

Iunusova, N V; Spirina, L V; Kondakova, L A; Kolomiets, A L; Chernyshova, A L; Koval', V D; Nedosekov, V V; Savenkova, O V

2013-01-01

We have examined for the first time the relationship between the expression of PAPP-A metalloproteinase and insulin-like growth factors (IGF-I, IGF-II, VEGF) and transcription factors (NF-kappaB, HIF-1) playing an important role in pathogenesis of cancer. We also demonstrated a positive association between the level of PAPP-A metalloproteinase and the level of growth (VEGF and IGF-I) and transcription factors (NF-kappaB p50, NF-kappaB p65, HIF-1alpha). The current findings suggest an important role of PAPP-A in regulation of bioavailability of IGF-I, VEGF, activated forms of NF-kappaB, and alpha-subunits of HIF-1 in endometrial tumors.

Calreticulin Regulates VEGF-A in Neuroblastoma Cells.

PubMed

Weng, Wen-Chin; Lin, Kuan-Hung; Wu, Pei-Yi; Lu, Yi-Chien; Weng, Yi-Cheng; Wang, Bo-Jeng; Liao, Yung-Feng; Hsu, Wen-Ming; Lee, Wang-Tso; Lee, Hsinyu

2015-08-01

Calreticulin (CRT) has been previously correlated with the differentiation of neuroblastoma (NB), implying a favorable prognostic factor. Vascular endothelial growth factor (VEGF) has been reported to participate in the behavior of NB. This study investigated the association of CRT and VEGF-A in NB cells. The expressions of VEGF-A and HIF-1α, with overexpression or knockdown of CRT, were measured in three NB cells (SH-SY5Y, SK-N-DZ, and stNB-V1). An inducible CRT NB cell line and knockdown CRT stable cell lines were also established. The impacts of CRT overexpression on NB cell apoptosis, proliferation, and differentiation were also evaluated. We further examined the role of VEGF-A in the NB cell differentiation via VEGF receptor blockade. Constitutive overexpression of CRT led to NB cell differentiation without proliferation. Thus, an inducible CRT stNB-V1 cell line was generated by a tetracycline-regulated gene system. CRT overexpression increased VEGF-A and HIF-1α messenger RNA (mRNA) expressions in SH-SY5Y, SK-N-DZ, and stNB-V1 cells. CRT overexpression also enhanced VEGF-A protein expression and secretion level in conditioned media in different NB cell lines. Knockdown of CRT decreased VEGF-A and HIF-1α mRNA expressions and lowered VEGF-A protein expression and secretion level in conditioned media in different NB cell lines. We further demonstrated that NB cell apoptosis was not affected by CRT overexpression in stNB-V1 cells. Nevertheless, overexpression of CRT suppressed cell proliferation and enhanced cell differentiation in stNB-V1 cells, whereas blockage of VEGFR-1 markedly suppressed the expression of neuron-specific markers including GAP43, NSE2, and NFH, as well as TrkA, a molecular marker indicative of NB cell differentiation. Our findings suggest that VEGF-A is involved in CRT-related neuronal differentiation in NB. Our work may provide important information for developing a new therapeutic strategy to improve the outcome of NB patients.

Quantification of STAT3 and VEGF expression for molecular diagnosis of lymph node metastasis in breast cancer

PubMed Central

Chen, Yujuan; Liu, Ya; Wang, Yu; Li, Wen; Wang, Xiaolu; Liu, Xuejuan; Chen, Yao; Ouyang, Chibin; Wang, Jing

2017-01-01

Abstract Background: Axillary lymph node metastasis is associated with increased risk of regional recurrence, distant metastasis, and poor survival in breast malignant neoplasm. Expression of signal transducer and activator of transcription 3 (STAT3) is significantly associated with tumor formation, migration, and invasion in various cancers. In addition, vascular endothelial growth factor (VEGF) expression could promote angiogenesis and increase the risk of tumorigenesis. To determine correlations among STAT3 expression, VEGF, and clinicopathological data on lymph node involvement in breast cancer patients after surgery. Methods: The mRNA expression levels of STAT3 and VEGFs were measured in 45 breast invasive ductal carcinoma tissues, 45 peritumoral tissues, and 45 adjacent nontumor tissues by real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR). Postoperative pathological examination revealed explicit axillary lymph node involvement in all patients. Results: Average mRNA levels of STAT3 and VEGFs were the highest in breast invasive ductal carcinoma tissues, followed by peritumoral tissues. High expression of STAT3 showed significant positive correlation with high axillary lymph node involvement and progesterone receptor (PR), VEGF-C, VEGF-D, and vascular endothelial growth factor receptor (VEGFR)-3 expression. The expression levels of STAT3, VEGF-C, and VEGFR-3 were significantly higher in the tumor tissues of patients with axillary lymph node metastasis than in those of patients without the metastasis. Expression levels of VEGF-C and VEGFR-3 were also significantly higher in peritumoral tissues of patients with axillary lymph node metastasis. Positive correlations were found between STAT3 and VEGF-C/-D mRNA levels. Conclusion: These data suggest that STAT3/VEGF-C/VEGFR-3 signaling pathway plays an important role in carcinogenesis and lymph-angiogenesis. Our findings suggest that STAT3 may be a potential molecular biomarker for predicting the involvement of axillary lymph nodes in breast cancer, and therapies targeting STAT3 may be important for preventing breast cancer metastasis. PMID:29137038

Vascular endothelial growth factor during hypoglycemia in patients with type 1 diabetes mellitus: relation to cognitive function and renin-angiotensin system activity.

PubMed

Kristensen, Peter Lommer; Høi-Hansen, Thomas; Boomsma, Frans; Pedersen-Bjergaard, Ulrik; Thorsteinsson, Birger

2009-10-01

In healthy adults, levels of vascular endothelial growth factor (VEGF) increase in response to mild hypoglycemia. VEGF is implicated in glucose transport over the blood-brain barrier, and the increase during hypoglycemia has been positively correlated with preservation of cognitive function during hypoglycemia. High activity in the renin-angiotensin system (RAS) is associated with an increased risk of severe hypoglycemia in patients with type 1 diabetes mellitus. Renin-angiotensin system possibly exerts its mechanism in hypoglycemia via VEGF. We studied the impact of mild hypoglycemia on plasma VEGF in patients with type 1 diabetes mellitus and high or low RAS activity and analyzed associations between VEGF levels and cognitive function during hypoglycemia. Eighteen patients with type 1 diabetes mellitus-9 with high and 9 with low RAS activity-underwent a single-blinded, placebo-controlled, crossover study with either mild hypoglycemia or stable glycemia. Cognitive function was assessed by the California Cognitive Assessment Package and the Alzheimer Quick Test. Nadir plasma glucose was 2.2 (0.3) mmol/L. During the control study, plasma VEGF did not change. During hypoglycemia, plasma VEGF increased from 39 to 58 pg/L in the high-RAS group (P = .004) and from 76 to 109 pg/L in the low-RAS group (P = .01), with no difference between RAS groups (P = .9). A weak association between reduced preservation of cognitive function during hypoglycemia and low VEGF response was observed. Plasma VEGF levels increase during mild, short-term hypoglycemia in patients with type 1 diabetes mellitus. The VEGF response is not dependent on RAS activity and only weakly associated with preservation of cognitive function during hypoglycemia. Thus, the previously described association between low RAS activity and better cognitive performance during hypoglycemia does not seem to be mediated by VEGF.

Adeno-associated virus type 8 vector–mediated expression of siRNA targeting vascular endothelial growth factor efficiently inhibits neovascularization in a murine choroidal neovascularization model

PubMed Central

Igarashi, Tsutomu; Miyake, Noriko; Fujimoto, Chiaki; Yaguchi, Chiemi; Iijima, Osamu; Shimada, Takashi; Takahashi, Hiroshi

2014-01-01

Purpose To assess the feasibility of a gene therapeutic approach to treating choroidal neovascularization (CNV), we generated an adeno-associated virus type 8 vector (AAV2/8) encoding an siRNA targeting vascular endothelial growth factor (VEGF), and determined the AAV2/8 vector’s ability to inhibit angiogenesis. Methods We initially transfected 3T3 cells expressing VEGF with the AAV2/8 plasmid vector psiRNA-VEGF using the H1 promoter and found that VEGF expression was significantly diminished in the transfectants. We next injected 1 μl (3 × 1014 vg/ml) of AAV2/8 vector encoding siRNA targeting VEGF (AAV2/8/SmVEGF-2; n = 12) or control vector encoding green fluorescent protein (GFP) (AAV2/8/GFP; n = 14) into the subretinal space in C57BL/6 mice. One week later, CNV was induced by using a diode laser to make four separate choroidal burns around the optic nerve in each eye. After an additional 2 weeks, the eyes were removed for flat mount analysis of the CNV surface area. Results Subretinal delivery of AAV2/8/SmVEGF-2 significantly diminished CNV at the laser lesions, compared to AAV8/GFP (1597.3±2077.2 versus 5039.5±4055.9 µm2; p<0.05). Using an enzyme-linked immunosorbent assay, we found that VEGF levels were reduced by approximately half in the AAV2/8/SmVEGF-2 treated eyes. Conclusions These results suggest that siRNA-VEGF can be expressed across the retina and that long-term suppression of CNV is possible through the use of stable AAV2/8-mediated siRNA-VEGF expression. In vivo gene therapy may thus be a feasible approach to the clinical management of CNV in conditions such as age-related macular degeneration. PMID:24744609

PLACENTAL DEFECTS IN ARNT-KNOCKOUT CONCEPTUS CORRELATE WITH LOCALIZED DECREASES IN VEGF-R2, ANG-1, AND TIE-2.

EPA Science Inventory

The aryl hydrocarbon receptor nuclear translocator (ARNT) is a transcriptional regulator that heterodimerizes with Per-ARNT-Sim (PAS) proteins. ARNT also dimerizes with hypoxia inducible factor1 (HIF1 ), inducing expression of vascular endothelial cell growth factor (VEGF) to p...

The use of a whole animal biophotonic model as a screen for the angiogenic potential of estrogenic compounds

USDA-ARS?s Scientific Manuscript database

Vascular endothelial growth factor (VEGF) is essential for normal vascular growth and development during wound repair. VEGF is estrogen responsive and capable of regulating its own receptor, vascular endothelial growth factor receptor-2 (VEGFR-2). Several agricultural pesticides (e.g., methoxychlor)...

Elevated levels of placental growth factor represent an adaptive host response in sepsis.

PubMed

Yano, Kiichiro; Okada, Yoshiaki; Beldi, Guido; Shih, Shou-Ching; Bodyak, Natalya; Okada, Hitomi; Kang, Peter M; Luscinskas, William; Robson, Simon C; Carmeliet, Peter; Karumanchi, S Ananth; Aird, William C

2008-10-27

Recently, we demonstrated that circulating levels of vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) are increased in sepsis (Yano, K., P.C. Liaw, J.M. Mullington, S.C. Shih, H. Okada, N. Bodyak, P.M. Kang, L. Toltl, B. Belikoff, J. Buras, et al. 2006. J. Exp. Med. 203:1447-1458). Moreover, enhanced VEGF/Flk-1 signaling was shown to contribute to sepsis morbidity and mortality. We tested the hypothesis that PlGF also contributes to sepsis outcome. In mouse models of endotoxemia and cecal ligation puncture, the genetic absence of PlGF or the systemic administration of neutralizing anti-PlGF antibodies resulted in higher mortality compared with wild-type or immunoglobulin G-injected controls, respectively. The increased mortality associated with genetic deficiency of PlGF was reversed by adenovirus (Ad)-mediated overexpression of PlGF. In the endotoxemia model, PlGF deficiency was associated with elevated circulating levels of VEGF, induction of VEGF expression in the liver, impaired cardiac function, and organ-specific accentuation of barrier dysfunction and inflammation. Mortality of endotoxemic PlGF-deficient mice was increased by Ad-mediated overexpression of VEGF and was blocked by expression of soluble Flt-1. Collectively, these data suggest that up-regulation of PlGF in sepsis is an adaptive host response that exerts its benefit, at least in part, by attenuating VEGF signaling.

CD147 induces up-regulation of vascular endothelial growth factor in U937-derived foam cells through PI3K/AKT pathway.

PubMed

Zong, JiaXin; Li, YunTian; Du, DaYong; Liu, Yang; Yin, YongJun

2016-11-01

Intraplaque angiogenesis has been recognized as an important risk factor for the rupture of advanced atherosclerotic plaques in recent years. CD147, also called Extracellular Matrix Metalloproteinase Inducer, has been found the ability to promote angiogenesis in many pathological conditions such as cancer diseases and rheumatoid arthritis via the up-regulation of vascular endothelial growth factor (VEGF), a critical mediator of angiogenesis. We investigated whether CD147 would also induce the up-regulation of VEGF in the foam cells formation process and explored the probable signaling pathway. The results showed the expression of CD147 and VEGF was significantly higher in U937-derived foam cells. After CD147 stealth siRNA transfection treatment, the production of VEGF was reduced depended on the inhibition efficiency of CD147 siRNAs.The special signaling pathway inhibitors LY294002, SP600125, SB203580 and U0126 were added to cultures respectively and the results showed LY294002 dose-dependently inhibited the expression of VEGF. The reduction of phospho-Akt was observed in both LY294002 and siRNA groups, suggested that the phosphatidylinositol 3-kinase/Akt pathway may be the probable signaling pathway underlying CD147 induced up-regulation of VEGF in U937-derived foam cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Phenotypic and gene expression modification with normal brain aging in GFAP-positive astrocytes and neural stem cells.

PubMed

Bernal, Giovanna M; Peterson, Daniel A

2011-06-01

Astrocytes secrete growth factors that are both neuroprotective and supportive for the local environment. Identified by glial fibrillary acidic protein (GFAP) expression, astrocytes exhibit heterogeneity in morphology and in the expression of phenotypic markers and growth factors throughout different adult brain regions. In adult neurogenic niches, astrocytes secrete vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) within the neurogenic niche and are also a source of special GFAP-positive multipotent neural stem cells (NSCs). Normal aging is accompanied by a decline in CNS function and reduced neurogenesis. We asked whether a decreased availability of astrocyte-derived factors may contribute to the age-related decline in neurogenesis. Determining alterations of astrocytic activity in the aging brain is crucial for understanding CNS homeostasis in aging and for assessing appropriate therapeutic targets for an aging population. We found region-specific alterations in the gene expression of GFAP, VEGF, and FGF-2 and their receptors in the aged brain corresponding to changes in astrocytic reactivity, supporting astrocytic heterogeneity and demonstrating a differential aging effect. We found that GFAP-positive NSCs uniquely coexpress both VEGF and its key mitotic receptor Flk-1 in both young and aged hippocampus, indicating a possible autocrine/paracrine signaling mechanism. VEGF expression is lost once NSCs commit to a neuronal fate, but Flk-1-mediated sensitivity to VEGF signaling is maintained. We propose that age-related astrocytic changes result in reduced VEGF and FGF-2 signaling, which in turn limits NSC and progenitor cell maintenance and contributes to decreased neurogenesis. © 2011 The Authors. Aging Cell © 2011 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.

Biologically active and biomimetic dual gelatin scaffolds for tissue engineering.

PubMed

Sánchez, P; Pedraz, J L; Orive, G

2017-05-01

We have designed, developed and optimized Genipin cross-linked 3D gelatin scaffolds that were biologically active and biomimetic, show a dual activity both for growth factor and cell delivery. Type B gelatin powder was dissolved in DI water. 100mg of genipin was dissolved in 10ml of DI water. Three genipin concentrations were prepared: 0.1%, 0.2% and 0.3% (w/v). Solutions were mixed at 40°C and under stirring and then left crosslinking for 72h. Scaffolds were obtained by punching 8 mm-cylinders into ethanol 70% solution for 10min and then freeze-drying. Scaffolds were biologically, biomechanically and morphologically evaluated. Cell adhesion and morphology of D1-Mesenchymal stem cells (MSCs) and L-929 fibroblast was studied. Vascular endothelial grwoth factor (VEGF) and Sonic hedgehog (SHH) were used as model proteins. Swelling ratio increased and younǵs module decreased along with the concentration of genipin. All scaffolds were biocompatible according to the toxicity test. MSC and L-929 cell adhesion improved in 0.2% of genipin, obtaining better results with MSCs. VEGF and SHH were released from the gels. This preliminary study suggest that the biologically active and dual gelatin scaffolds may be used for tissue engineering approaches like bone regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

Bisphenol A induces proliferative effects on both breast cancer cells and vascular endothelial cells through a shared GPER-dependent pathway in hypoxia.

PubMed

Xu, Fangyi; Wang, Xiaoning; Wu, Nannan; He, Shuiqing; Yi, Weijie; Xiang, Siyun; Zhang, Piwei; Xie, Xiao; Ying, Chenjiang

2017-12-01

Based on the breast cancer cells and the vascular endothelial cells are both estrogen-sensitive, we proposed a close reciprocity existed between them in the tumor microenvironment, via shared molecular mechanism affected by environmental endocrine disruptors (EDCs). In this study, bisphenol A (BPA), via triggering G-protein estrogen receptor (GPER), stimulated cell proliferation and migration of bovine vascular endothelial cells (BVECs) and breast cancer cells (SkBr-3 and MDA-MB-231) and enhanced tumor growth in vivo. Moreover, the expression of both hypoxia inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) were up-regulated in a GPER-dependent manner by BPA treatment under hypoxic condition, and the activated GPER induced the HIF-1α expression by competitively binding to caveolin-1 (Cav-1) and facilitating the release of heat shock protein 90 (HSP90). These findings show that in a hypoxic microenvironment, BPA promotes HIF-1α and VEGF expressions through a shared GPER/Cav-1/HSP90 signaling cascade. Our observations provide a probable hypothesis that the effects of BPA on tumor development are copromoting relevant biological responses in both vascular endothelial and breast cancer cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

VEGF-121 plasma level as biomarker for response to anti-angiogenetic therapy in recurrent glioblastoma.

PubMed

Martini, Maurizio; de Pascalis, Ivana; D'Alessandris, Quintino Giorgio; Fiorentino, Vincenzo; Pierconti, Francesco; Marei, Hany El-Sayed; Ricci-Vitiani, Lucia; Pallini, Roberto; Larocca, Luigi Maria

2018-05-10

Vascular endothelial growth factor (VEGF) isoforms, particularly the diffusible VEGF-121, could play a major role in the response of recurrent glioblastoma (GB) to anti-angiogenetic treatment with bevacizumab. We hypothesized that circulating VEGF-121 may reduce the amount of bevacizumab available to target the heavier isoforms of VEGF, which are the most clinically relevant. We assessed the plasma level of VEGF-121 in a brain xenograft model, in human healthy controls, and in patients suffering from recurrent GB before and after bevacizumab treatment. Data were matched with patients' clinical outcome. In athymic rats with U87MG brain xenografts, the level of plasma VEGF-121 relates with tumor volume and it significantly decreases after iv infusion of bevacizumab. Patients with recurrent GB show higher plasma VEGF-121 than healthy controls (p = 0.0002) and treatment with bevacizumab remarkably reduced the expression of VEGF-121 in plasma of these patients (p = 0.0002). Higher plasma level of VEGF-121 was significantly associated to worse PFS and OS (p = 0.0295 and p = 0.0246, respectively). Quantitative analysis of VEGF-121 isoform in the plasma of patients with recurrent GB could be a promising predictor of response to anti-angiogenetic treatment.

Apatinib inhibits VEGF signaling and promotes apoptosis in intrahepatic cholangiocarcinoma.

PubMed

Peng, Hong; Zhang, Qiuyang; Li, Jiali; Zhang, Ning; Hua, Yunpeng; Xu, Lixia; Deng, Yubin; Lai, Jiaming; Peng, Zhenwei; Peng, Baogang; Chen, Minhu; Peng, Sui; Kuang, Ming

2016-03-29

Tumor cells co-express vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFRs) that interact each other to support a self-sustainable cell growth. So far, this autocrine VEGF loop is not reported in human intrahepatic cholangiocarcinoma (ICC). Apatinib is a highly selective VEGFR2 inhibitor, but its effects on ICC have not been investigated. In this study, we reported that VEGF and phosphorylated VEGFR2 were expressed at a significantly high level in ICC patient tissues (P<0.05). In vitro, treating ICC cell lines RBE and SSP25 with recombinant human VEGF (rhVEGF) induced phosphorylation of VEGFR1 (pVEGFR1) and VEGFR2 (pVEGFR2); however, only the VEGFR2 played a role in the anti-apoptotic cell growth through activating a PI3K-AKT-mTOR anti-apoptotic signaling pathway which generated more VEGF to enter this autocrine loop. Apatinib inhibited the anti-apoptosis induced by VEGF signaling, and promoted cell death in vitro. In addition, Apatinib treatment delayed xenograft tumor growth in vivo. In conclusion, the autocrine VEGF/VEGFR2 signaling promotes ICC cell survival. Apatinib inhibits anti-apoptotic cell growth through suppressing the autocrine VEGF signaling, supporting a potential role for using Apatinib in the treatment of ICC.

Apatinib inhibits VEGF signaling and promotes apoptosis in intrahepatic cholangiocarcinoma

PubMed Central

Zhang, Ning; Hua, Yunpeng; Xu, Lixia; Deng, Yubin; Lai, Jiaming; Peng, Zhenwei; Peng, Baogang; Chen, Minhu; Peng, Sui; Kuang, Ming

2016-01-01

Tumor cells co-express vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFRs) that interact each other to support a self-sustainable cell growth. So far, this autocrine VEGF loop is not reported in human intrahepatic cholangiocarcinoma (ICC). Apatinib is a highly selective VEGFR2 inhibitor, but its effects on ICC have not been investigated. In this study, we reported that VEGF and phosphorylated VEGFR2 were expressed at a significantly high level in ICC patient tissues (P<0.05). In vitro, treating ICC cell lines RBE and SSP25 with recombinant human VEGF (rhVEGF) induced phosphorylation of VEGFR1 (pVEGFR1) and VEGFR2 (pVEGFR2); however, only the VEGFR2 played a role in the anti-apoptotic cell growth through activating a PI3K-AKT-mTOR anti-apoptotic signaling pathway which generated more VEGF to enter this autocrine loop. Apatinib inhibited the anti-apoptosis induced by VEGF signaling, and promoted cell death in vitro. In addition, Apatinib treatment delayed xenograft tumor growth in vivo. In conclusion, the autocrine VEGF/VEGFR2 signaling promotes ICC cell survival. Apatinib inhibits anti-apoptotic cell growth through suppressing the autocrine VEGF signaling, supporting a potential role for using Apatinib in the treatment of ICC. PMID:26967384

Successful treatment of refractory TAFRO syndrome with elevated vascular endothelial growth factor using thyroxine supplements.

PubMed

Oka, Satoko; Ono, Kazuo; Nohgawa, Masaharu

2018-04-01

Although the clinical significance of hypothyroidism in TAFRO syndrome is unknown, vascular endothelial growth factor (VEGF) levels decreased with improvements in the condition of our refractory TAFRO cases after thyroxine supplement therapy. Our results indicate that elevated VEGF levels are a potential factor in the pathogenesis and anasarca of TAFRO syndrome with hypothyroidism.

Chemical synthesis and X-ray structure of a heterochiral {D-protein antagonist plus vascular endothelial growth factor} protein complex by racemic crystallography.

PubMed

Mandal, Kalyaneswar; Uppalapati, Maruti; Ault-Riché, Dana; Kenney, John; Lowitz, Joshua; Sidhu, Sachdev S; Kent, Stephen B H

2012-09-11

Total chemical synthesis was used to prepare the mirror image (D-protein) form of the angiogenic protein vascular endothelial growth factor (VEGF-A). Phage display against D-VEGF-A was used to screen designed libraries based on a unique small protein scaffold in order to identify a high affinity ligand. Chemically synthesized D- and L- forms of the protein ligand showed reciprocal chiral specificity in surface plasmon resonance binding experiments: The L-protein ligand bound only to D-VEGF-A, whereas the D-protein ligand bound only to L-VEGF-A. The D-protein ligand, but not the L-protein ligand, inhibited the binding of natural VEGF(165) to the VEGFR1 receptor. Racemic protein crystallography was used to determine the high resolution X-ray structure of the heterochiral complex consisting of {D-protein antagonist + L-protein form of VEGF-A}. Crystallization of a racemic mixture of these synthetic proteins in appropriate stoichiometry gave a racemic protein complex of more than 73 kDa containing six synthetic protein molecules. The structure of the complex was determined to a resolution of 1.6 Å. Detailed analysis of the interaction between the D-protein antagonist and the VEGF-A protein molecule showed that the binding interface comprised a contact surface area of approximately 800 Å(2) in accord with our design objectives, and that the D-protein antagonist binds to the same region of VEGF-A that interacts with VEGFR1-domain 2.

The adapter protein, Grb10, is a positive regulator of vascular endothelial growth factor signaling.

PubMed

Giorgetti-Peraldi, S; Murdaca, J; Mas, J C; Van Obberghen, E

2001-07-05

Vascular endothelial growth factor (VEGF) is an important regulator of vasculogenesis and angiogenesis. Activation of VEGF receptors leads to the recruitment of SH2 containing proteins which link the receptors to the activation of signaling pathways. Here we report that Grb10, an adapter protein of which the biological role remains unknown, is tyrosine phosphorylated in response to VEGF in endothelial cells (HUVEC) and in 293 cells expressing the VEGF receptor KDR. An intact SH2 domain is required for Grb10 tyrosine phosphorylation in response to VEGF, and this phosphorylation is mediated in part through the activation of Src. In HUVEC, VEGF increases Grb10 mRNA level. Expression of Grb10 in HUVEC or in KDR expressing 293 cells results in an increase in the amount and in the tyrosine phosphorylation of KDR. In 293 cells, this is correlated with the activation of signaling molecules, such as MAP kinase. By expressing mutants of Grb10, we found that the positive action of Grb10 is independent of its SH2 domain. Moreover, these Grb10 effects on KDR seem to be specific since Grb10 has no effect on the insulin receptor, and Grb2, another adapter protein, does not mimic the effect of Grb10 on KDR. In conclusion, we propose that VEGF up-regulates Grb10 level, which in turn increases KDR molecules, suggesting that Grb10 could be involved in a positive feedback loop in VEGF signaling.

Antitumor and antiangiogenic activities of anti-vascular endothelial growth factor hairpin ribozyme in human hepatocellular carcinoma cell cultures and xenografts.

PubMed

Li, Li-Hua; Guo, Zi-Jian; Yan, Ling-Ling; Yang, Ji-Cheng; Xie, Yu-Feng; Sheng, Wei-Hua; Huang, Zhao-Hui; Wang, Xue-Hao

2007-12-21

To study the effectiveness and mechanisms of anti- human vascular endothelial growth factor (hVEGF) hairpin ribozyme on angiogenesis, oncogenicity and tumor growth in a hepatocarcinoma cell line and a xenografted model. The artificial anti-hVEGF hairpin ribozyme was transfected into hepatocarcinoma cell line SMMC-7,721 and, subsequently, polymerase chain reaction (PCR) and reverse transcription polymerase chain reaction (RT-PCR) were performed to confirm the ribozyme gene integration and transcription. To determine the effects of ribozyme ,VEGF expression was detected by semiquantitative RT-PCR and enzyme liked immunosorbent assay (ELISA). MTT assay was carried out to measure the cell proliferation. Furthermore,the transfected and control cells were inoculated into nude mice respectively, the growth of cells in nude mice and angiogenesis were observed. VEGF expression was down-regulated sharply by ribozyme in transfected SMMC-7,721 cells and xenografted tumor. Compared to the control group, the transfected cells grew slower in cell cultures and xenografts, and the xenograft formation was delayed as well. In addition, the microvessel density of the xenografted tumor was obviously declined in the transfected group. As demonstrated by microscopy,reduction of VEGF production induced by ribozyme resulted in a significantly higher cell differentiation and less proliferation vigor in xenografted tumor. Anti-hVEGF hairpin ribozyme can effectively inhibit VEGF expression and growth of hepatocarcinoma in vitro and in vivo. VEGF is functionally related to cell proliferation, differentiation and tumori-genesis in hepatocarcinoma.

Endocrine gland-derived vascular endothelial growth factor in rat pancreas: genetic expression and testosterone regulation.

PubMed

Morales, Angélica; Morimoto, Sumiko; Díaz, Lorenza; Robles, Guillermo; Díaz-Sánchez, Vicente

2008-05-01

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an endothelial cell mitogen, expressed essentially in steroidogenic cells. Recently, the expression of EG-VEGF in normal human pancreas and pancreatic adenocarcinoma has been demonstrated. Epidemiologically, pancreatic carcinogenesis is more frequent in males than females, and given that androgen receptors and testosterone biotransformation have been described in pancreas, we hypothesized that testosterone could participate in the regulation of EG-VEGF expression. In this study, we investigated the regulation of EG-VEGF gene expression by testosterone in normal rat pancreatic tissue and rat insulinoma cells (RINm5F). Total RNA was extracted from rat pancreas and cultured cells. Gene expression was studied by real-time PCR and protein detection by immunohistochemistry. Serum testosterone was quantified by RIA. Results showed that EG-VEGF is expressed predominantly in pancreatic islets and vascular endothelium, as well as in RINm5F cells. EG-VEGF gene expression was lower in the pancreas of rats with higher testosterone serum levels. A similar effect that was reverted by flutamide was observed in testosterone-treated RINm5F cells. In summary, testosterone down-regulated EG-VEGF gene expression in rat pancreatic tissue and RINm5F cells. This effect could be mediated by the androgen receptor. To our knowledge, this is the first time that a direct effect of testosterone on EG-VEGF gene expression in rat pancreas and RINm5F cells is demonstrated.

Photo-controlled aptamers delivery by dual surface gold-magnetic nanoparticles for targeted cancer therapy.

PubMed

Zhao, Jian; Tu, Keyao; Liu, Yanlei; Qin, Yulei; Wang, Xiwei; Qi, Lifeng; Shi, Donglu

2017-11-01

Dual surfaced dumbbell-like gold magnetic nanoparticles (Au-Fe 3 O 4 ) were synthesized for targeted aptamers delivery. Their unique biological properties were characterized as a smart photo-controlled drug carrier. DNA aptamers targeting vascular endothelial growth factor (VEGF) were assembled onto the surface of Au-Fe 3 O 4 by electrostatic absorption. The binding capacity of the nanoparticles with VEGF aptamers was confirmed by gel electrophoresis. The targeted recognization of ovarian cancer cells by the aptamers-functionalized Au-Fe 3 O 4 nanoparticles (Apt-Au-Fe 3 O 4 NPs) was observed by confocal microscopy. Apt-Au-Fe 3 O 4 was found to bind with SKOV-3 ovarian cancer cells specifically, leading to marked intracellular release of aptamers upon plasmon-resonant light (605nm) radiation, and to enhance the in vitro inhibition against tumor cell proliferation. The results show high potential of Apt-Au-Fe 3 O 4 as a targeted cancer hyperthermia carrier by remote control with high spatial/temporal resolution. Copyright © 2017. Published by Elsevier B.V.

VEGF signaling inside vascular endothelial cells and beyond

PubMed Central

Eichmann, Anne; Simons, Michael

2014-01-01

Vascular endothelial growth factor-A (VEGF-A) has long been recognized as the key regulator of vascular development and function in health and disease. VEGF is a secreted polypeptide that binds to transmembrane tyrosine kinase VEGF receptors on the plasma membrane, inducing their dimerization, activation and assembly of a membrane-proximal signaling complex. Recent studies have revealed that many key events of VEGFR signaling occur inside the endothelial cell and are regulated by endosomal receptor trafficking. Plasma membrane VEGFR interacting molecules, including vascular guidance receptors Neuropilins and Ephrins also regulate VEGFR endocytosis and trafficking. VEGF signaling is increasingly recognized for its roles outside of the vascular system, notably during neural development, and blood vessels regulate epithelial branching morphogenesis. We review here recent advances in our understanding of VEGF signaling and its biological roles. PMID:22366328

Anti-angiogenic efficacy of 5′-triphosphate siRNA combining VEGF silencing and RIG-I activation in NSCLCs

PubMed Central

Meng, Gang; Xu, Chun; Song, Yong; Wei, Jiwu

2015-01-01

Short interfering RNA (siRNA) targeting angiogenic factors and further inhibiting tumor angiogenesis, is one of the potent antitumor candidates for lung cancer treatment. However, this strategy must be combined with other therapeutics like chemotherapy. In this study, we designed a 5′-triphosphate siRNA targeting VEGF (ppp-VEGF), and showed that ppp-VEGF exerted three distinct antitumor effects: i) inhibition of tumor angiogenesis by silencing VEGF, ii) induction of innate immune responses by activating RIG-I signaling pathway, and thus activate antitumor immunity, iii) induction of apoptosis. In a subcutaneous model of murine lung cancer, ppp-VEGF displayed a potent antitumor effect. Our results provide a multifunctional antitumor molecule that may overcome the shortages of traditional antiangiogenic agents. PMID:26336994

Adverse effects of anticancer agents that target the VEGF pathway.

PubMed

Chen, Helen X; Cleck, Jessica N

2009-08-01

Antiangiogenesis agents that target the VEGF/VEGF receptor pathway have become an important part of standard therapy in multiple cancer indications. With expanded clinical experience with this class of agents has come the increasing recognition of the diverse adverse effects related to disturbance of VEGF-dependent physiological functions and homeostasis in the cardiovascular and renal systems, as well as wound healing and tissue repair. Although most adverse effects of VEGF inhibitors are modest and manageable, some are associated with serious and life-threatening consequences, particularly in high-risk patients and in certain clinical settings. This Review examines the toxicity profiles of anti-VEGF antibodies and small-molecule inhibitors. The potential mechanisms of the adverse effects, risk factors, and the implications for selection of patients and management are discussed.