Expression Of Angiopoietin-1 Research Articles

Tumour Angiogenesis in Uveal Melanoma Is Related to Genetic Evolution.

Increased angiogenesis is associated with a higher metastasis- and mortality rate in uveal melanoma (UM). Recently, it was demonstrated that genetic events, such as 8q-gain and BAP1-loss, influence the level of immune infiltrate. We aimed to determine whether genetic events, and specific cytokines, relate to angiogenesis in UM. Data from UM patients who underwent enucleation between 1999 and 2008 were analysed. Microvascular density (MVD) and the presence of infiltrating immune cells were determined with immunohistochemistry (IHC) and immunofluorescence in 43 cases. Chromosome status, BAP1 IHC and mRNA expression of angiogenesis-related genes were known in 54 cases. Tumours with monosomy 3/BAP1-loss showed a higher MVD compared to tumours with disomy 3/normal BAP1 expression (p = 0.008 and p = 0.004, respectively). Within BAP1-positive lesions (n = 20), 8q-gain did not relate to MVD (p = 0.51). A high MVD was associated with an increased expression of angiopoietin 2 (ANGPT2) (p = 0.041), Von Willebrand Factor (VWF) (p = 0.010), a decreased expression of vascular endothelial growth factor B (VEGF-B) (p = 0.024), and increased numbers of tumour-infiltrating macrophages (CD68+, p = 0.017; CD68+CD163+, p = 0.031) and lymphocytes (CD4+, p = 0.027). Concluding, vascular density of UM relates to its genetic profile: Monosomy 3 and BAP1-loss are associated with an increased MVD, while an early event (gain of 8q) is not independently related to MVD, but may initiate a preparation phase towards development of vessels. Interestingly, VEGF-B expression is decreased in UM with a high MVD.

Translational study associated to a phase II study evaluating the activity of pazopanib in patients (pts) with advanced/metastatic liposarcoma (LPS): A joint Spanish Sarcoma Group (GEIS) and German Interdisciplinary Sarcoma Group (GISG) study.

11067 Background: GEIS 30 was a phase II study showing moderate activity of pazopanib in well-differentiated/dedifferentiated LPS (cohort A:37 pts, Progression free Survival (PFS) at 12 weeks (w) 43.2%) and no activity in Myxoid/round cell LPS (cohort B: 15 pts, PFS at 12w 13.3%). The present study aims to identify tumor and plasma biomarkers that are differently expressed in long responders (LRs) PFS > 24 w. Methods: Serum samples and paraffin-blocks at diagnosis were collected for 28 pts in cohort A and 11 in B. A total of 13 pts were LRs. Serum samples were obtained at baseline, after 3 w of treatment and at progression. A panel of 15 cytokines and growth factors were evaluated using Luminex technology (Millipore). Paraffin-blocks were evaluated for microvessel density (MVD) by CD31 immunostaining and Image Pro-Plus 7.0 Image Analysis System (Media-Cybernetics). For RNA expression analysis, the Oncology Biomarker Panel with probes for 2559 transcripts was used (HTG Molecular Diagnostics). Results: Serum cytokines showed that expression of angiopoietin (AGO) and BMP9 decreases during treatment, whereas GCSF increases. In addition, AGO and BMP overexpression at baseline was associated with worse prognosis in arm A (p = 0.09) and B (p = 0.01) respectively. No differences between study arms and outcome were appreciated by MVD. Gene expression revealed differences in some immunomodulators: PDL-1 was correlated with serum cytokines VEGFD (p = 0.04) and LEPTIN (p = 0.02); and PD-1 with VEGFD (p = 0.04), LEPTIN (p = 0.02), VEGFA (p = 0.02) and ANGIO (p = 0.03). PD1, in addition,was overexpressed in LRs (p = 0.05). Interestingly, three groups were identified in cohort A according to gene expression: Cluster 1, characterized by short-responder patients with the shortest overall survival, whereas cluster 3 (40% LRs) and 2 (63.6% LRs) showed longer survival rates (14.3%, 45.5% and 30% respectively) (p = 0.001). Conclusions: Gene expression profiling unveils three WD/DD-LPS biotypes according to their response to pazopanib, which could be potentially used to select pts for treatment

Platelet microvesicles promote the recovery of neurological function in mouse model of cerebral infarction by inducing angiogenesis

The aim of this study is to investigate the effect of PMVs on mice with ischemic cerebral infarction and its mechanism. Male C57BL/6 mice were selected, and the right focal cortical infarction model was established via cauterization under a microscope and randomly divided into sham operation (Sham) group, normal saline control (Saline) group and platelet microvesicles intervention (PMVs) group. At 1 h after modeling, 5 μL of PMVs (50 μg/mL) or normal saline was injected into the lateral ventricle. The neurological function of mice in each group was evaluated at 1, 3, 7, 14 and 28 d after modeling. After 28 d, the cerebral infarction area was detected via 2,3,5-triphenyltetrazolium chloride (TTC) staining. At 7 and 28 d after modeling, the blood vessel density, proliferation rate of new vessels and encapsulation rate of pericytes were detected via immunofluorescence staining. Moreover, the changes in cerebral cortical blood flow at the infarction side were detected before modeling and at 7 and 28 d after modeling, respectively. Finally, the expressions of proangiogenic factors vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1) and N-Cadherin were detected via Western blotting at 3, 7 and 28 d after modeling. PMVs could promote the improvement of neurological function and significantly reduce the cerebral infarction volume in mice with cerebral infarction. PMVs promoted proliferation of new vessels and increased blood vessel density at the infarction edge in mice with cerebral infarction. PMVs could increase the encapsulation rate of pericytes at the infarction edge and improve the permeability of blood-brain barrier in mice with cerebral infarction. PMVs could increase the cerebral cortical blood flow perfusion in mice with cerebral infarction. PMVs could increase proangiogenic factors in brain tissues in mice with cerebral infarction. PMVs could significantly improve the recovery of neurological function in mice with cerebral infarction, which is closely related to the ability of PMVs to promote angiogenesis at the infarction edge. The possible mechanism is that PMVs facilitate angiogenesis after cerebral infarction through promoting the expressions of VEGF, Ang-1 and N-Cadherin. More importantly, the new vessels promoted by PMVs have complete structure and perfect function, and can improve the cerebral blood flow perfusion at the infarction side.

Fibulin-7 is overexpressed in glioblastomas and modulates glioblastoma neovascularization through interaction with angiopoietin-1.

Glioblastoma (GBM) is pathologically characterized by highly malignant neoplastic cells, focal necrosis and aberrant blood vessels composed of disorganized endothelial cells and pericytes. The recent cancer microarray database revealed upregulation of fibulin-7 (Fbln7), a member of the fibulin family, but provided no information on the tissue localization or biological function. In the present study, we demonstrated that Fbln7 is markedly overexpressed by the GBM tissue among astrocytic tumors, and immunolocalized mainly to endothelial cells and pericytes of the glomeruloid and hypertrophied microvessels. The production of Fbln7 by endothelial cells and pericytes was confirmed in cultured human umbilical vein endothelial cells (HUVEC) and human brain vascular pericytes (HBVP) and vascular endothelial growth factor (VEGF) stimulated the Fbln7 expression in HUVEC. Fbln7 bound to angiopoietin-1, but not angiopoietin-2 or Tie2 receptor, through interaction between the N-terminal portions of Fbln7 and angiopoietin-1, and it blocked phosphorylation of Tie2 receptor in HUVEC. In a coculture assay using HUVEC and HBVP, multilayered and irregular-shaped tube-like structures of HUVEC were induced by treatment with a high concentration of VEGF. This was accompanied by Fbln7 overproduction by HUVEC and angiopoietin-1 expression by HBVP. The production of aberrant VEGF-induced tube-like structures was attenuated by treatment with antibody or synthetic peptides specific to the Fbln7 N-terminal domain or knockdown of Fbln7. These data demonstrate that Fbln7 is overexpressed by endothelial cells and pericytes of the abnormal microvessels in GBM, and suggest that Fbln7 may contribute to the aberrant vessel formation by modulation of the angiopoietin-1/angiopoietin-2-Tie2 axis.

Targeting pericyte–endothelial cell crosstalk by circular RNA-cPWWP2A inhibition aggravates diabetes-induced microvascular dysfunction

The crosstalk between vascular pericytes and endothelial cells (ECs) is critical for microvascular stabilization and remodeling; however, the crosstalk is often disrupted by diabetes, leading to severe and even lethal vascular damage. Circular RNAs are a class of endogenous RNAs that regulate several important physiological and pathological processes. Here we show that diabetes-related stress up-regulates cPWWP2A expression in pericytes but not in ECs. In vitro studies show that cPWWP2A directly regulates pericyte biology but indirectly regulates EC biology via exosomes carrying cPWWP2A. cPWWP2A acts as an endogenous miR-579 sponge to sequester and inhibit miR-579 activity, leading to increased expression of angiopoietin 1, occludin, and SIRT1. In vivo studies show that cPWWP2A overexpression or miR-579 inhibition alleviates diabetes mellitus-induced retinal vascular dysfunction. By contrast, inhibition of cPWWP2A-mediated signaling by silencing cPWWP2A or overexpressing miR-579 aggravates retinal vascular dysfunction. Collectively, this study unveils a mechanism by which pericytes and ECs communicate. Intervention of cPWWP2A or miR-579 expression may offer opportunities for treating diabetic microvascular complications.

Lysosomal Pathways and Autophagy Distinctively Control Endothelial Cell Behavior to Affect Tumor Vasculature

Cancer cell-stromal cell crosstalk is orchestrated by a plethora of ligand-receptor interactions generating a tumor microenvironment (TME) which favors tumor growth. The high pro-angiogenic nature of the TME perpetuates the chaotic network of structurally immature, low pericyte-covered vessels characteristic of the tumor vasculature. We previously demonstrated that chloroquine (CQ) -a lysosomotropic agent used as first-generation autophagy blocker in clinical trials- induced tumor vessel normalization and reduced tumor hypoxia. CQ improved both vessel structure and maturation, whereas the conditional knockout of the crucial autophagy gene Atg5 in endothelial cells (ECs) did not, thus highlighting a potential differential role for EC-associated autophagy and the lysosomes in pathological tumor angiogenesis. However, how CQ or ATG5-deficiency in ECs affect angiogenic signals regulating EC-pericyte interface and therefore vessel maturation, remains unknown. Here, we show that in ECs CQ constrained VEGF-A-mediated VEGF receptor (VEGFR)2 phosphorylation, a driver of angiogenic signaling. In the presence of CQ we observed increased expression of the decoy receptor VEGFR1 and of a lower molecular weight form of VEGFR2, suggesting receptor cleavage. Consequently, VEGF-A-driven EC spheroid sprouting was reduced by CQ treatment. Furthermore, CQ significantly affected the transcription and secretion of platelet-derived growth factor (PDGF)-AB/BB (upregulated) and Endothelin-1 (EDN1, downregulated), both modulators of perivascular cell (PC) behavior. In contrast, silencing of ATG5 in ECs had no effect on VEGFR2 to VEGFR1 ratio nor on PDGFB and EDN1 expression. Accordingly, mice harboring B16F10 melanoma tumors treated with CQ, displayed both an increased number of αSMA+ PCs covering tumor vessels and co-expressed PDGF receptor-β, enabling PDGF ligand dependent recruitment. Moreover, upon CQ treatment the tumoral expression of angiopoietin-1 (Angpt1), which retains mural cells, and induces vessel stabilization by binding to the EC-localized cognate receptor (TIE2), was increased thus supporting the vessel normalization function of CQ. These features associated with improved tumor vasculature were not phenocopied by the specific deletion of Atg5 in ECs. In conclusion, this study further unravels endothelial cell autonomous and non-autonomous mechanisms by which CQ “normalizes” the intercellular communication in the tumor vasculature independent of autophagy.

LncRNA MALAT1 up-regulates VEGF-A and ANGPT2 to promote angiogenesis in brain microvascular endothelial cells against oxygen-glucose deprivation via targetting miR-145.

Stroke is one of the leading causes of death and long-term disability around the world. Angiogenesis is supposed to protect brain microvascular endothelial cells (BMECs) from oxidative and ischemic stress. Previous studies indicated that interaction between metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and miR-145 was involved in myocardial ischemia reperfusion, suggesting MALAT1 and miR-145 were also mediated with the progress of angiogenesis and cell migration in oxygen–glucose deprivation (OGD)-induced BMECs. The present study aimed to investigate the functional roles of MALAT1 in regulating miR-145 and its downstream pro-angiogenesis factors, vascular endothelial growth factor (VEGF)-A and Angiopoietin-2 (ANGPT2) during the progress of angiogenesis in OGD-induced BMECs. An in vitro OGD model was employed in mouse BMECs to mimic brain hypoxic and ischemic conditions; MTT was used to determine cell viability. qRT-PCR was used to determine the expression of long non-coding RNA (lncRNA)-MALAT1 and miR-145 under OGD conditions; in vitro tube formation assay was used to investigate angiogenic effect of MALAT1 and miR-145. The relationship between lncRNA-MALAT1/miR-145 and miR-145/VEGF-A/ANGPT2 was evaluated by qRT-PCR and Western blot, and direct binding was assessed using dual luciferase assay. Results showed that the levels of lncRNA-MALAT1 and miR-145 were up-regulated in OGD-induced BMECs. miR-145 functioned as an anti-angiogenic and pro-apoptotic factor in OGD treated BMECs via down-regulating VEGF-A and ANGPT2 directly. While lncRNA-MALAT1 enhanced the expressions of VEGF-A and ANGPT2 by targetting miR-145 to promote angiogenesis and proliferation of BMECs under OGD conditions. Our present study revealed the inhibitory functions of miR-145 on angiogenesis through direct targetting on VEGF-A and ANGPT2 for the first time and proved the protective role of lncRNA-MALAT1 for BMECs under OGD conditions through the direct regulation of miR-145.

Dl-3-N-butylphthalide promotes angiogenesis and upregulates sonic hedgehog expression after cerebral ischemia in rats.

SummaryIntroductionDl‐3‐N‐butylphthalide (NBP), a small molecule drug used clinically in the acute phase of ischemic stroke, has been shown to improve functional recovery and promote angiogenesis and collateral vessel circulation after experimental cerebral ischemia. However, the underlying molecular mechanism is unknown.AimsTo explore the potential molecular mechanism of angiogenesis induced by NBP after cerebral ischemia.ResultsNBP treatment attenuated body weight loss, reduced brain infarct volume, and improved neurobehavioral outcomes during focal ischemia compared to the control rats (P < 0.05). NBP increased the number of CD31+ microvessels, the number of CD31+/BrdU+ proliferating endothelial cells, and the functional vascular density (P < 0.05). Further study demonstrated that NBP also promoted the expression of vascular endothelial growth factor and angiopoietin‐1 (P < 0.05), which was accompanied by upregulated sonic hedgehog expression in astrocytes in vivo and in vitro.ConclusionNBP treatment promoted the expression of vascular endothelial growth factor and angiopoietin‐1, induced angiogenesis, and improved neurobehavioral recovery. These effects were associated with increased sonic hedgehog expression after NBP treatment. Our results broadened the clinical application of NBP to include the later phase of ischemia.

Angiopoietin 1 influences ischemic reperfusion renal injury via modulating endothelium survival and regeneration

BackgroundDamage to the endothelium due to ischemia reperfusion injury (IRI) leads to a disruption of the microvasculature, which could be influenced by angiopoietin 1 via its effects on endothelium. We investigated the physiological and therapeutic roles of angiopoietin 1 in renal IRI using angiopoietin 1 knockout and over-expression mice.MethodsRenal IRI was induced by clamping the right renal artery seven days after left uninephrectomy for 25 min followed by reperfusion. A whole body angiopoietin 1 knockout was achieved by induction with tamoxifen. The renal tubule over-expression of angiopoietin 1 was induced by doxycycline.ResultsIn the normal mice, the renal expression of angiopoietin 1 increased 7 days to 14 days after IRI. The angiopoietin 1 knockout caused a delay in the recovery of renal function, less tubular regeneration and more residual tubular necrosis. The endothelial density was lower and the VE-cadherin protein loss was greater in the knockout mice. The over-expression of angiopoietin 1 attenuated the tubular necrosis and renal function impairment 1 and 3 days after IRI. The loss of the endothelium was ameliorated in the over-expression mice. This protective effect was associated with the up-regulation of the gene expression of epidermal growth factor, hepatocyte growth factor, and insulin like growth factor-1 and less tubular apoptosis. The over-expression of angiopoietin 1 stimulated tumor necrosis factor-α, C-C chemokine receptor type 2 and CX3C chemokine receptor 1 inflammatory gene expression, but did not influence macrophage infiltration.ConclusionsAltogether, the augmentation and downregulation of angiopoietin 1 attenuated renal damage and impaired renal recovery, respectively, by influencing the survival/regeneration of the endothelium. The manipulation of angiopoietin 1 represents a novel therapeutic approach for the treatment of ischemic kidney injury.

Exosomes from hypoxia-treated human adipose-derived mesenchymal stem cells enhance angiogenesis through VEGF/VEGF-R.

We previously reported that co-transplantation of exosomes from hypoxia-preconditioned adipose mesenchymal stem cells (ADSCs) improves the neoangiogenesis and survival of the grafted tissue. This study aimed to investigate the molecular mechanism of this protective effect. Exosomes were collected from normoxia-treated (nADSC-Exo) or hypoxia--treated (hypADSC-Exo) human ADSCs, and their pro-angiogenic capacity was evaluated in human umbilical vein endothelial cells (HUVECs) and a nude mouse model of subcutaneous fat grafting. Protein array was used to compare the exosome-derived proteins between nADSC-Exo and hypADSC-Exo. Compared with the nADSC-Exo group and untreated control, hypADSC-Exo treatment significantly promoted proliferation, migration and tube-formation capability of HUVECs. Protein array revealed that the levels of vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), fibroblast growth factor (FGF) and their receptors (VEGF-R2, VEGF-R3), and monocyte chemoattractant protein 2 (MCP-2), monocyte chemoattractant protein 4 (MCP-4) were significantly higher in the hypADSC-Exo than in the nADSC-Exo. In the nude mice model of fat grafting, immunofluorescence of CD31 showed that hypADSC-Exo dramatically improved neovascularization around the graft. Furthermore, compared with nADSC-Exo and control groups, cotransplantation of hypADSC-Exo significantly increased the protein expression of EGF, FGF, VEGF/VEGF-R, angiopoietin-1(Ang-1) and tyrosine kinase with immunoglobulin-like and EGF-like domains 1(Tie-1, an angiopoietin receptor) in the grafted tissue at 30 days after transplantation. Immunohistochemical analysis demonstrated that hypADSC-Exo treatment significantly increased VEGF-R expression in the grafted tissue. Exosomes from hypoxia-treated human ADSCs possess a higher capacity to enhance angiogenesis in fat grafting, at least partially, via regulating VEGF/VEGF-R signaling.

Angiopoietin-2 Induces Angiogenesis &lt;i&gt;via&lt;/i&gt; Exosomes in Human Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) is the most common primary liver cancer and is a highly vascularized solid tumor. Angiopoietin-2 (ANGPT2) has been described as an attractive target for antiangiogenic therapy. The expression of ANGPT2 in tumor-derived exosomes remains unknown. Methods: We detected the ANGPT2 expression in HCC-derived exosomes by the immunoblotting, enzyme-linked immunosorbent assay and immunogold labeling, then observed exosomal ANGPT2 internalization and recycling by the confocal laser scanning microscopy. We used two HCC cell lines (Hep3B and MHCC97H) to overexpress ANGPT2 by lentivirus infection or knockdown ANGPT2 by the CRISPR/Cas system, then isolated exosomes to coculture with human umbilical vein endothelial cells (HUVECs) and observed the angiogenesis by the Matrigel microtubule formation assay, transwell migration assay, wound healing assay, cell counting kit-8 assay, immunoblotting and in vivo tumorigenesis assay. Findings: We found that HCC-derived exosomes carried ANGPT2 and delivered it into HUVECs by exosome endocytosis, this delivery led to a notable increase in angiogenesis by a Tie2-independent pathway. Concomitantly, we observed that HCC cell-secreted exosomal ANGPT2 was recycled by recipient HUVECs and might be reused. In addition, the CRISPR-Cas systems to knock down ANGPT2 significantly inhibited the angiogenesis induced by HCC cell-secreted exosomal ANGPT2, and obviously suppressed the epithelial-mesenchymal transition activation in HCC. Interpretation: These results reveal a novel pathway of tumor angiogenesis induced by HCC cell-secreted exosomal ANGPT2 that is different from the classic ANGPT2/Tie2 pathway. This way may be a potential therapeutic target for antiangiogenic therapy. Funding Statement: National Natural Science Foundation of China (81672420, 81702406, 81673433); National Engineering and Technology Research Center for New drug Druggability Evaluation (Seed Program of Guangdong Province, 2017B090903004); Key Laboratory of Malignant Tumor Molecular Mechanism and Translational Medicine of Guangzhou Bureau of Science and Information Technology. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: Tissue and serum samples were collected from patients after obtaining informed consent in accordance with a protocol approved by the Ethics Committee of Sun Yat-sen Memorial Hospital (Guangzhou, China). All experimental procedures involving animals were performed according to the Guide for the Care and Use of Laboratory Animals (National Institutes of Health publication No. 85-23, revised 2011) and in accordance with the institutional ethical guidelines for animal experiments.

Hypoxic Condition Up-Regulates the Expression of Angiopoietin-2 in ADSCs

Wound healing requires abundant nutrition and blood supply, thus angiogenesis is a vital stage in this process. Angiogenesis involves diverse kinds of immune cells, growth factors, cytokines and inhibitors. ADSCs, especially ADSCs cultured in hypoxic condition, are reported to be able to facilitate angiogenesis and promote wound healing process. Significant efforts have been made on the development of ADSCs-based therapies with wound-healing applications. Here the results showed that expression of Angiopoietin-2 (ANGPT2) in ADSCs was up-regulated in the hypoxic condition.

Targeting the ERβ/Angiopoietin-2/Tie-2 Signaling-Mediated Angiogenesis with the FDA-Approved Anti-Estrogen Faslodex to Increase the Sunitinib Sensitivity in RCC

Sunitinib has been used as the first-line therapy to suppress the metastatic clear cell Renal Cell Carcinoma (ccRCC) as it could function via suppressing the tumor growth and angiogenesis. Yet most ccRCC tumors may still regrow due to the development of sunitinibresistance, and detailed mechanisms remain unclear. Here, we found the estrogen receptor β (ERβ) in RCC cells might function via increasing the endothelial cell tube formation to alter the sensitivity to sunitinib treatment. Mechanism dissection revealed that ERβ could function via transcriptional regulation with direct binding to the promoter to increase the cytokine Angiopoietin-2 expression in the ccRCC cells. The up-regulated Angiopoietin-2 could then increase the Tie-2 phosphorylation in the endothelial Huvec cells to promote the angiogenesis tube formation that results in increasing the endothelial cell resistance to sunitinib treatment. Preclinical study using an in vivo mouse RCC model also confirm in vitro data. Targeting this newly identified ERβ/Angiopoietin2/Tie-2 signaling-increased angiogenesis tube formation with the FDAapproved anti-estrogen, ICI 182,780 (Faslodex) may help in the development of a novel combined therapy with sunitinib to better suppress the ccRCC progression. Funding Statement: This work was partially supported by the URMC Urology research fund and the George Whipple Professorship Endowment. Declaration of Interests: The authors declare no potential conflicts of interest. Ethics Approval Statement: The Institutional Animal Care and Use Committee (IACUC) review board at University of Rochester Medical Center approved the studies.

Expression of Angiopoietin and VEGF in Cervical Cancer and its Clinical Significance.

ObjectiveThe aim of this study was to evaluate the expression of Angiopoietin-1 (Ang-1), Angiopoietin-2 (Ang-2) and vascular endothelial growth factor (VEGF) in cervical cancer and its clinical significance.MethodsImmunohistochemical assay was used to examine the expression of Ang-1/2 and VEGF in tumor tissue from 56 cervical squamous cell carcinoma patients treated with operation only (SCC-O group), as well as 51 subjects with cervical squamous cell carcinoma treated with neoadjuvant radiotherapy (SCC-RCO group, n=28) or neoadjuvant chemotherapy (SCC-CO group, n=23). Both microvessel density (MVD) and lymphatic vessel density (LVD) were examined in the three groups through detection of CD34 and D2-40 expression in respective tissue samples.ResultsWith the progression of cervical cancer, the positive expression scores of Ang-2 and VEGF were significantly increased (p<0.05). Compared with surgical intervention, neoadjuvant chemoradiotherapy significantly reduced the positive expression scores of Ang-1, Ang-2, and VEGF in cervical cancer tissues (p<0.05). The MVD values of the SCC-CO and SCC-RO groups were significantly reduced as compared to the SCC-O group (p<0.05). Similarly, the LVD values of the SCC-CO and SCC-RO groups were also significantly reduced when compared to those of the SCC-O group (p<0.05). However, LVD values of the SCC-CO and SCC-RO groups were not statistical different (p>0.05).ConclusionAng-1, Ang-2 and VEGF may play an important role in the development of cervical cancer. Mutual synergism of Ang-2 and VEGF demonstrated a close relationship with the generation of cervical blood and lymphatic vessels. Cervical cancer radiotherapy and chemotherapy could significantly inhibit the formation of blood vessels and lymphatic vessels in tumor tissue.

Abnormal morphological and functional nature of bone marrow stromal cells provides preferential support for survival of acute myeloid leukemia cells.

Hematopoietic progenitors, residing in the bone marrow (BM) niche, are supported by mesenchymal stromal cells (MSCs). Cytogenetic and molecular aberrations in these progenitors lead to acute myeloid leukemia (AML). The BM-MSC role in leukemogenesis is not fully elucidated. In the current study, an ex-vivo system of patient's own stroma (POS), best mimicking the in-vivo BM niche, has been developed aiming to unravel interactions and crosstalk between MSCs and AML cells. POS derived from AML patients at diagnosis (Dx), relapse (Rx) and remission (Rm) was compared to healthy donor MSCs in terms of their morphology, growth pattern, support of leukemia cell viability and cytokine profile. Compared to control MSCs, POS (Dx/Rx, Rm) demonstrated a reduced proliferation rate (35%), significantly slower expansion, enlarged cell area (3-4-fold) and provided preferential support to leukemic cells of the same individual. Cytokine profiling showed significantly higher secreted phosphoprotein-1 (SPP1) expression in Dx/Rx and Rm POS compared to healthy MSCs. Additionally, the angiopoietin-1 expression was elevated in Dx/Rx POS with a further increase in the AML cell presence. In conclusion, the fact that POS derived in active disease and remission exhibited similar morphological and functional characteristics, might imply the involvement of the BM niche in leukemogenesis.

Evaluating the Effect of Vitamin C on Myocardial Angiogenesis Under Oxidative Stress Induced by Exhaustive Exercise in Rat

Background: The main purpose of the present study was to assess the effects of exhaustive swimming with the consumption of a vitamin C supplement on indices of myocardial oxidative stress and gene expression related to angiogenesis. Methods: Wistar rats were randomly divided into six groups of normal (C), 100 and 200 mg/kg of vitamin C, (VC100 and VC200), exercise with 100 and 200 mg/kg of vitamin C (Ex+VC100 and Ex+VC200) and exercise without treatment (Ex). Finally, the serum activity of serum creatine phosphokinase (CK) and lactate dehydrogenase (LDH) and heart tissue oxidant/antioxidant parameters, besides gene expression of Vascular endothelial growth factor-B (VEGF-B), angiopoietin 1 (ANGPT-1) and matrix metalloproteinases 2 (MMP-2) was measured. Results: Significant increase in LDH level was seen in group Ex which was remarkably attenuated in group Ex+VC200 (p&lt;0.001). The tissue oxidative stress was observed in group Ex where daily intake of vitamin C could remarkably regulate this property (p&lt;0.01). Vitamin C could ameliorate significant upper gene expression of VEGF-B and MMP-2 remarkably (p&lt;0.05). Conclusion: Oxidative condition in myocardial besides over expression of MMP-2, could be concluded as a detrimental condition resulting from exhaustive swimming that continued by the proteolytic release of CK and LDH from the muscle. Upper gene expression of VEGF-B and MMP-2 besides no changes of ANGPT-1 can be concluded as an early stage of angiogenesis. All these events were somehow attenuated by vitamin C which confirmed its beneficial effects as an antioxidant and the role of oxidation properties in the regulation of angiogenesis.

Abstract 16605: Peripheral Blood-Derived Myeloid Subtypes Are Associated With Cardiac Allograft Vasculopathy

Introduction: The evidence for innate immunity’s role in cardiac allograft rejection does not necessarily extend to cardiac allograft vasculopathy (CAV), and predictors of CAV remain elusive. We hypothesize that circulating monocytes and their derived macrophage subtypes, as well as associated inflammatory and angiogenesis markers, correlate with CAV. Methods: 49 consecutive heart transplant recipients over 2 years post-transplant were enrolled. Peripheral blood mononuclear cells were isolated, with monocytes stained and measured by flow cytometry for classical (CD14 ++ /CD16 - ), intermediate (CD14 ++ /CD16 + ), and nonclassical (CD14 lo /CD16 ++ ) subtypes. Monocytes were cultured into macrophages, driven by M-CSF, and assayed for polarization markers CD86 and CD206. Serum concentrations of multiple factors including IL8, IL6, TNFα, angiopoietin-2, and VEGF-A were measured by immunoassay. CAV was assessed by angiogram and intravascular ultrasound (IVUS). Results: 22 patients had no significant CAV (Stanford class I-II) while 27 had significant CAV by angiogram or IVUS (class III-IV). Other than time since transplant (77±13 vs 135±12 months), baseline characteristics of the two groups were similar. There were no differences between monocyte subgroups in isolation, but when combined with derived macrophage polarization, patients with CAV tended toward lower M2 (CD206 + ) macrophage production (0.18±0.04%) than those without CAV (0.35±0.11%). The CAV monocyte/macrophage profile was distinct from that of a reference native CAD population. IL8 was higher late post-transplant (&gt;7.5 years) compared to early post-transplant (1.8±0.3 vs 1.0±0.1 pg/ml). There was also higher expression of angiopoietin-2 with time after transplant and with CAV. Conclusions: The reduced ability of CAV patients to generate regulatory M2 macrophages and their higher circulating IL8 and angiopoietin-2, both linked to inflammatory macrophage signatures, support a model in which pro-inflammatory myeloid phenotypes are connected to development of CAV, and notably, these circulating monocyte and macrophage subtypes differ from those of native CAD. These cell-based and paired circulating markers could be useful to differentiate high vs. low CAV risk phenotypes.

Mediation of FoxO1 in Activated Neuroglia Deficient for Nucleoside Diphosphate Kinase B during Vascular Degeneration

The pathogenesis of diabetic retinopathy is closely associated with the breakdown of the neurovascular unit including the glial cells. Deficiency of nucleoside diphosphate kinase B (NDPK-B) results in retinal vasoregression mimicking diabetic retinopathy. Increased retinal expression of Angiopoietin-2 (Ang-2) initiates vasoregression. In this study, Müller cell activation, glial Ang-2 expression, and the underlying mechanisms were investigated in streptozotocin-induced diabetic NDPK-B deficient (KO) retinas and Müller cells isolated from the NDPK-B KO retinas. Müller cells were activated and Ang-2 expression was predominantly increased in Müller cells in normoglycemic NDPK-B KO retinas, similar to diabetic wild type (WT) retinas. Diabetes induction in the NDPK-B KO mice did not further increase its activation. Additionally, cultured NDPK-B KO Müller cells were more activated and showed higher Ang-2 expression than WT cells. Müller cell activation and Ang-2 elevation were observed upon high glucose treatment in WT, but not in NDPK-B KO cells. Moreover, increased levels of the transcription factor forkhead box protein O1 (FoxO1) were detected in non-diabetic NDPK-B KO Müller cells. The siRNA-mediated knockdown of FoxO1 in NDPK-B deficient cells interfered with Ang-2 upregulation. These data suggest that FoxO1 mediates Ang-2 upregulation induced by NDPK-B deficiency in the Müller cells and thus contributes to the onset of retinal vascular degeneration.

Angiopoietin expression in ovine corpora lutea during the luteal phase: Effects of nutrition, arginine and follicle stimulating hormone

The aim of this study was to evaluate angiopoietin (ANGPT) 1 and 2, and tyrosine-protein kinase receptor 2 (TIE2) expression in the corpora lutea (CL) of FSH-treated, or non-treated sheep administered arginine (Arg) or vehicle (saline, Sal), and fed a control (C), excess (O) or restricted (U) diet. Ewes from each dietary group were treated with Arg or Sal (experiment 1), and with FSH (experiment 2). Luteal tissues were collected at the early-, mid- and/or late-luteal phases of the estrous cycle. Protein and mRNA expression was determined using immunohistochemistry followed by image analysis, and quantitative RT-PCR, respectively. The results demonstrated that ANGPT1 and TIE2 proteins were localized to luteal capillaries and endothelial cells of larger blood vessels, and ANGPT2 was localized to tunica media of larger blood vessels. TIE2 protein was also present in luteal cells. In experiment 1, ANGPT1 protein expression was greater in O than C during early- and mid-luteal phases, and was greatest during late-luteal phase, less at the mid- and least at the early-luteal phase; 2) TIE2 protein expression was greatest at the mid-, less at the early- and least at the late-luteal phase; 3) ANGPT1 and 2 mRNA expression was greater at the mid- and late- than the early-luteal phase, and TIE2 mRNA expression was greatest at the late-, less at the mid- and least at the early-luteal phase. The ANGPT1/2 ratio was less at the early- than mid- or late-luteal phases. In experiment 2, ANGPT1 protein expression was greater in O during the mid-luteal phase than in other groups, and was greater at the mid- than early-luteal phase. TIE2 protein expression was highest at the mid-, less at the early- and least during the late-luteal phase. ANGPT1 and 2, and TIE2 mRNA expression was higher at the mid- than the early-luteal phase. During mid-luteal phase, ANGPT1 mRNA expression was greater in C than O and U, ANGPT2 was greatest in C, less in O and least in U, and TIE2 mRNA expression was greater in C than O and U. The ANGPT1/2 ratio was higher in U than in any other group. Comparison of FSH vs. Sal treatment effects (experiment 2 vs. experiment 1) demonstrated that FSH affected ANGPT1 and/or -2, and TIE2 protein and mRNA expression depending on luteal phase and/or diet. Thus, expression of ANGPTs and TIE2 in the CL changes during the luteal lifespan, indicating their involvement in luteal vascular formation, stabilization and degradation. Moreover, this study has demonstrated that plane of nutrition and/or FSH treatment affect the ANGPT system, and may alter luteal vascularity and luteal function in sheep.

Liver Angiopoietin-2 Is a Key Predictor of De Novo or Recurrent Hepatocellular Cancer After Hepatitis C Virus Direct-Acting Antivirals.

Recent reports suggested that direct acting antivirals (DAAs) might favor hepatocellular carcinoma (HCC). In study 1, we studied the proangiogenic liver microenvironment in 242 DAA‐treated chronic hepatitis C patients with advanced fibrosis. Angiopoietin‐2 (ANGPT2) expression was studied in tissue (cirrhotic and/or neoplastic) from recurrent, de novo, nonrecurrent HCC, or patients never developing HCC. Circulating ANGPT2,vascular endothelial growth factor (VEGF), and C‐reactive protein (CRP) were also measured. In study 2, we searched for factors associated with de novo HCC in 257 patients with cirrhosis of different etiologies enrolled in a dedicated prospective study. Thorough biochemical, clinical, hemodynamic, endoscopic, elastographic, and echo‐Doppler work‐up was performed in both studies. In study 1, no patients without cirrhosis developed HCC. Of 183 patients with cirrhosis, 14 of 28 (50.0%) with previous HCC recurred whereas 21 of 155 (13.5%) developed de novo HCC. Patients with recurrent and de novo HCCs had significantly higher liver fibrosis (LF) scores, portal pressure, and systemic inflammation than nonrecurrent HCC or patients never developing HCC. In recurrent/de novo HCC patients, tumor and nontumor ANGPT2 showed an inverse relationship with portal vein velocity (PVv; r = –0.412, P = 0.037 and r = –0.409, P = 0.047 respectively) and a positive relationship with liver stiffness (r = 0.526, P = 0.007; r = 0.525, P = 0.003 respectively). Baseline circulating VEGF and cirrhotic liver ANGPT2 were significantly related (r = 0.414, P = 0.044). VEGF increased during DAAs, remaining stably elevated at 3‐month follow‐up, when it significantly related with serum ANGPT2 (r = 0.531, P = 0.005). ANGPT2 expression in the primary tumor or in cirrhotic tissue before DAAs was independently related with risk of HCC recurrence (odds ratio [OR], 1.137; 95% confidence interval [CI], 1.044‐1.137; P = 0.003) or occurrence (OR, 1.604; 95% CI, 1.080‐2.382; P = 0.019). In study 2, DAA treatment (OR, 4.770; 95% CI, 1.395‐16.316; P = 0.013) and large varices (OR, 3.857; 95% CI, 1.127‐13.203; P = 0.032) were independent predictors of de novo HCC. Conclusion: Our study indicates that DAA‐mediated increase of VEGF favors HCC recurrence/occurrence in susceptible patients, that is, those with more severe fibrosis and splanchnic collateralization, who already have abnormal activation in liver tissues of neo‐angiogenetic pathways, as shown by increased ANGPT2. (Hepatology 2018; 00:000‐000).