Associations of plasma angiostatin and amyloid-ß and tau levels in Alzheimer's disease.

Angiostatin, an endogenous angiogenesis inhibitor generated by the proteolytic cleavage of plasminogen, was recently reported to contribute to the development of Alzheimer's disease (AD). However, whether there are pathological changes in angiostatin levels in individuals with AD dementia is unclear, and whether plasma angiostatin has a relationship with major AD pathological processes and cognitive impairment remains unknown. To examine plasma angiostatin levels in patients with AD dementia and investigate the associations of angiostatin with blood and cerebrospinal fluid (CSF) AD biomarkers, we conducted a cross-sectional study including 35 cognitively normal control (CN) subjects and 59 PiB-PET-positive AD dementia patients. We found that plasma angiostatin levels were decreased in AD dementia patients compared to CN subjects. Plasma angiostatin levels were negatively correlated with plasma Aß42 and Aß40 levels in AD dementia patients and positively correlated with CSF total tau (t-tau) levels and t-tau/Aß42 in AD dementia patients with APOE-ε4. In addition, plasma angiostatin levels had the potential to distinguish AD from CN. These findings suggest a link between angiostatin and AD pathogenesis and imply that angiostatin might be a potential diagnostic biomarker for AD.

Assessment of selected angiogenesis markers in the serum of middle-aged male patients with plaque psoriasis.

Local angiogenesis accompanies inflammation in psoriasis-affected skin. To determine the serum concentrations of selected pro- and anti-angiogenic factors and their interrelationships in patients with plaque psoriasis. The study included 41 men diagnosed with psoriasis, aged 43.5 ± 11.7 years. The Psoriasis Area and Severity Index score was 23.4 ± 5.2 points. The control group consisted of 38 healthy, age-matched men. The levels of pro-angiogenic cytokines and angiogenesis inhibitors, including fibroblast growth factor 1 (FGF-1), vascular endothelial growth factor A (VEGF-A), endostatin, and angiostatin, were determined from the serum of patients and controls using enzyme-linked immunosorbent assays. Compared with controls, patients with psoriasis had a significantly lower concentration of FGF-1 (P = .01) but higher concentrations of endostatin (P = .04) and angiostatin (P = .02). The concentration of VEGF-A was also higher in patients with psoriasis but not significantly (P = .25). The concentration of C-reactive protein (CRP) was significantly higher among patients with psoriasis than controls (P < .0001). Among controls, CRP concentrations did not correlate significantly with the concentrations of FGF-1, VEGF-A, endostatin, or angiostatin. Among patients with psoriasis, CRP concentrations correlated moderately with the concentrations of VEGF-A (r = .35; P = .02) and angiostatin (r = .31; P = .04). The concentration of VEGF-A correlated positively with PASI (r = .05; P = .0009) and BSA values (r = .39; P = .01). Psoriasis is associated with an altered systemic balance between pro-angiogenic and anti-angiogenic factors. The increase in serum angiogenesis inhibitors may be associated with unfavorable changes in the development of coronary collateral circulation. However, the clinical significance of this has not yet been established.

Effect of Diosmin Administration in Patients with Chronic Venous Disorders on Selected Factors Affecting Angiogenesis.

Diosmin is a natural compound with a wide range of biological activity, e.g., it improves lymphatic drainage, supports microcirculation, and increases venous tone, and venous elasticity, hence, it is applied in the pharmacotherapy of chronic venous disorders (CVD). The aim of this study was to assess the correlation between diosmin administration (2 × 600 mg daily) in patients suffering from CVD and the levels of selected factors influencing angiogenesis, which are involved in CVD pathophysiology. Thirty-five CVD patients were examined. Levels of plasma tumor necrosis factor alpha (TNF alpha), vascular endothelial growth factor (VEGF-A and VEGF-C); angiostatin, interleukin 6 (IL-6), fibroblast growth factor 2 (FGF2); and plasminogen (PLG) were measured with an Elisa assay before and after three months of diosmin administration. The clinical symptoms of CVD were monitored using ultrasound images, echo Doppler assay, visual analogue scale (VAS), and measurement of the leg circumference. The average content of TNF alpha, VEGF-C, VEGF-A IL-6, and FGF2 decreased after the therapy with diosmin in a significant manner; with p < 0.001, p < 0.05, p < 0.05, p < 0.01, and p < 0.01, respectively, and a significant (p < 0.05) increase in the plasma angiostatin level after the three-month treatment was found. A significant (p < 0.05) decrease in edema and the average leg circumference of the patients was observed after the therapy. Diosmin influences the angiogenic and inflammatory mechanisms involved in the pathophysiology of edema presented in patients with a different class of CVD.

Antiangiogenesis and medical therapy failure in intracranial atherosclerosis.

Intracranial atherosclerotic disease (ICAD) is one of the most common causes of stroke worldwide and the one with the worst prognosis. In this study, we assessed the hypothesis that the balance of circulating pro- and antiangiogenic factors plays a role in the evolution of the disease and can be used as a potential marker for the disease course and a target for treatment. Seventy-four patients with severe ICAD were enrolled in this prospective observational study, medically optimized, and followed for 6 months. Thirteen pro- and eight antiangiogenic factors were measured in the participants' serum using a sandwich multiplex ELISA. Angiogenic profiles were calculated using principal component analysis. We tested the association between angiogenic profiles and recurring cerebrovascular events despite intensive medical therapy, disability at 6 months after enrollment, and angiographic neovascularization in patients who failed medical treatment and underwent indirect revascularization surgery. There is a strong association between a functionally antiangiogenic profile and recurrent stroke or TIA in patients with ICAD (OR = 7.2, CI 2.4-34.4). Multivariable regression analysis showed that this antiangiogenic profile was also associated with poor functional status after 6 months (p = 0.002), independent from other clinical features such as history of previous stroke, diabetes, and age. In patients who failed medical management and underwent indirect revascularization surgery, high endostatin and angiostatin levels were also associated with low angiographic neovascularization (p = 0.02). The results of this study point to the striking importance of antiangiogenesis as a determinant of ICAD patient prognosis and suggest a possible new target for therapy.

Maternal plasma angiogenic and inflammatory factor profiling in foetal Down syndrome.

OBJECTIVE AND DESIGN: Angiogenic factors are proteins that are related to certain foetal chromosomal abnormalities. The aim of this study was to determine the concentration of 60 angiogenic factors in the plasma of women with offspring possessing trisomy 21/Down syndrome (DS). METHOD: After analysing karyotyping results, we selected 20 patients with foetuses possessing DS, and for the control group, we selected 28 healthy patients with uncomplicated pregnancies who delivered healthy newborns at term (i.e., 15-18 weeks of gestation). To assess the concentration of proteins in the blood plasma, we used a protein macroarray which enabled simultaneous determination of 60 angiogenic factors per sample. RESULTS: We observed a statistically significant increase in the concentration of these five angiogenic and inflammatory factors: TGFb1 (p = 0.039), angiostatin (p = 0.0142), I-309 (p = 0.0476), TGFb3 (p = 0.0395), and VEGF-D (p = 0.0173)-compared to concentrations in patients with healthy foetuses. CONCLUSION: Our findings suggest that angiogenic factors may play role in DS pathogenesis.

Human neutrophil elastase mediates fibrinolysis shutdown through competitive degradation of plasminogen and generation of angiostatin.

BACKGROUND: A subset of trauma patients undergo fibrinolysis shutdown rather than pathologic hyperfibrinolysis, contributing to organ failure. The molecular basis for fibrinolysis shutdown in trauma is incompletely understood. Elastase released from primed/activated human neutrophils (HNE) has historically been described as fibrin(ogen)olytic. However, HNE can also degrade plasminogen (PLG) to angiostatin (ANG), retaining the kringle domains but not the proteolytic function, and could thereby compete for generation of active plasmin by tissue plasminogen activator (tPA). We hypothesized that HNE can drive fibrinolysis shutdown rather than fibrinolysis. METHODS: Turbidometry was performed using light scatter (λ = 620 nm) in a purified fibrinogen + PLG system and in healthy citrate plasma clotted with Ca/thrombin ± tPA, ±HNE, and ±ANG to evaluate HNE effects on fibrinolysis, quantified by time to transition midpoint (Tm). ΔTm from control is reported as percent of control ±95% CI. Purified HNE coincubated with PLG or tPA was analyzed by western blot to identify cleavage products. Exogenous HNE was mixed ex vivo with healthy volunteer blood (n = 7) and used in TEG ± tPA to evaluate effects on fibrinolysis. RESULTS: HNE did not cause measurable fibrinolysis on fibrin clots, clotted plasma, or whole blood as assessed by turbidometry or TEG in the absence of tPA. Upon tPA treatment, all three methods of evaluating fibrinolysis showed delays and decreases in fibrinolysis caused by HNE relative to control: fibrin clot turbidometry ΔTm = 110.7% (CI 105.0-116.5%), clotted citrate plasma (n = 6 healthy volunteers) ΔTm = 126.1% (CI 110.4-141.8%), and whole blood native TEG (n = 7 healthy volunteers) with ΔLY30 = 28% (p = 0.043). Western blot analysis of HNE-PLG co-incubation confirmed that HNE generates angiostatin K1-3, and plasma turbidity assays treated with angiostatin K1-3 delayed fibrinolysis. CONCLUSION: HNE degrades PLG and generates angiostatin K1-3, which predominates over HNE cleavage of fibrin(ogen). These findings suggest that neutrophil release of elastase may underlie trauma-induced fibrinolytic shutdown.

Different contributions of angiostatin and endostatin in angiogenesis impairment in systemic sclerosis: a cohort study.

OBJECTIVES: To determine the concentrations of circulating endostatin and angiostatin in patients with systemic sclerosis (SSc) and to assess its relationship to disease subsets, evolution phase, organ involvement and nailfold capillaroscopic changes. METHODS: Endostatin and angiostatin serum levels were measured by ELISA in a cohort of 57 patients with SSc, and correlated with disease subsets, evolution phase, organ involvement and nailfold capillaroscopic changes. RESULTS: Endostatin and angiostatin serum levels were significantly higher in patients with SSc than in healthy controls. Also, angiostatin was elevated in diffuse cutaneous SSc (dcSSc) and limited cutaneous SSc (lcSSc), but not in pre-SSc, while endostatin was increased in all SSc subsets. Moreover, endostatin was augmented in lcSSc, with or without CREST syndrome, whereas angiostatin was increased exclusively in patients with CREST. Analysis according to disease evolution phase found that endostatin was elevated in all phases while angiostatin was only significantly higher in intermediate and late phases of disease. Analysis regarding organ involvement revealed that angiostatin was significantly higher in patients with osteoarticular involvement and with more serious lung affection; no significant differences were found for endostatin. Finally, endostatin was significantly increased in all nailfold capillaroscopy stages, while angiostatin was only elevated in active and late phases. CONCLUSIONS: In accordance with previous studies, we found that endostatin and angiostatin concentrations are elevated in SSc patients. Additionally, we recognised the important role that endostatin might play as an early disease marker and realized that angiostatin is a marker of late disease and relates to lung disease severity.

Statin treatment decreases serum angiostatin levels in patients with ischemic heart disease.

AIM: Angiogenesis and chronic inflammation are known to be co-dependent in atherosclerosis and cardiovascular diseases. This study was undertaken to investigate whether simvastatin could affect serum levels of angiostatin, a potent endogenous inhibitor of neovascularization, in patients with ischemic heart disease (IHD). MAIN METHODS: Twenty-six patients with clinically confirmed IHD and hypercholesterolemia were assigned 40 mg/day of simvastatin for 8 weeks. Levels of lipid metabolism, C-reactive protein (C-RP) and other biochemical parameters in serum samples were measured using biochemical analyzer. Serum angiostatin levels were determined by Western blot. Association of serum angiostatin levels with total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and C-RP levels was evaluated. KEY FINDINGS: Simvastatin therapy improved the main parameters of lipid metabolism, including statistically significant (P < 0.05) reductions in TC (by 46%) and LDL-C (by 42%), and decreased inflammatory marker C-RP (by 32%), as compared with the baseline. Simvastatin treatment resulted in marked reduction of serum angiostatin level (by 80% in comparison with baseline, P < 0.05). Strong positive correlations between serum angiostatin level versus concentrations of TC, LDL-C, and C-RP were demonstrated before onset of the study (r = 0.48311, 0.6252, and 0.653, respectively) and after simvastatin therapy (r = 0.67752, 0.6485, and 0.8244, respectively). SIGNIFICANCE: We describe for the first time novel pleiotropic effect of statin therapy associated with decrease of serum angiostatin levels. Thus, circulating angiostatin represents an independent additional risk marker for cardiovascular events and could be applied as potential supplementary indicator for evaluation of statin therapy efficacy.

Serum angiostatin levels in patients with Behçet's disease: does angiogenesis play a role in the pathogenesis of Behçet's disease?

Angiogenesis plays an important role in the pathogenesis of inflammatory diseases, but the possible role of angiogenesis in Behçet's disease (BD) has not yet been studied. The aim of this study was to determine angiostatin levels in patients with BD and the role of angiogenesis in the pathogenesis of the disease. Thirty-seven patients with BD (mean age: 28·6±5·4 years, mean disease duration: 9·3±3·7 years) and 18 healthy controls were enrolled to the study. Twenty-four patients were in active and 13 patients were in inactive stage of the disease. The mean serum angiostatin level of patients with BD was 113·9±53·2 and 60·7±20·1 ng/ml in healthy controls. The mean serum angiostatin level was 142·7±43·1 ng/ml in active and 86·9±15·5 ng/ml in inactive patients with BD. Serum angiostatin levels were significantly high in patients with BD compared with healthy controls (P<0·001) and it was significantly high in active patients compared with inactive patients with BD (P<0·001). In inactive patients with BD, serum angiostatin concentrations were found to be higher compared with healthy controls (P<0·01). In active BD patients, the mean serum angiostatin level was correlated with the deep vein thrombosis (r = 0·482, P = 0·05), uveitis (r = 0·582, P = 0·01), and arthritis (r = 0·492, P = 0·05). According to these results; elevated serum angiostatin levels in patients with BD suggest the possible role of angiogenesis in the pathogenesis of the disease and its high levels in inactive Behçet's patients is related with the continuous activation of the disease even in the subclinical period.

Serum levels of angiogenic and anti-angiogenic factors: their prognostic relevance in locally advanced hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a prototype tumor wherein angiogenesis plays a vital role in its progression. The role of VEGF, a major angiogenic factor in HCC is known; however, the role of anti-angiogenic factors simultaneously with the angiogenic factors has not been studied before. Hence, in this study, the serum levels of major angiogenic [Vascular Endothelial Growth Factor (VEGF), angiopoietin-2 (Ang-2)] and anti-angiogenic (endostatin, angiostatin) factors were analyzed and correlated with clinico-radiological features and with outcome. A total of 150 patients (50 HCC, 50 cirrhosis and 50 chronic hepatitis) and 50 healthy controls were enrolled in this study. Serum levels of VEGF, Ang-2, endostatin, and angiostatin were estimated by enzyme-linked immunosorbent assay. HCC shows significantly elevated serum levels of angiogenic factors VEGF and Ang-2 and of anti-angiogenic factors endostatin and angiostatin. ROC curve analysis for serum VEGF yielded an optimal cut-off value of 225.14 pg/ml, with a sensitivity of 78 % and specificity of 84.7 % for a diagnosis of HCC and its distinction from other group. Using this value, the univariate and multivariate analysis revealed significantly poor outcome in patients with higher levels of serum VEGF (p = 0.009). Combinatorial analysis revealed that patients with higher levels of both angiogenic and anti-angiogenic factors showed poor outcome. Serum VEGF correlates with poor survival of HCC patients and, therefore, serves as a non-invasive biomarker of poor prognosis. Moreover, elevated levels of anti-angiogenic factors occur endogenously in HCC patients.

Linoleic acid enhances angiogenesis through suppression of angiostatin induced by plasminogen activator inhibitor 1.

BACKGROUND: The intake of dietary fatty acids is highly correlated with the risk of various cancers. Linoleic acid (LA) is the most abundant polyunsaturated fat in the western diet, but the mechanism(s) by fatty acids such as LA modulate cancer cells is unclear. In this study, we examined the role of LA in various steps in gastric cancer progression. METHODS: The difference in gene expression between LA-treated and untreated OCUM-2MD3 gastric carcinoma cells was examined by mRNA differential display. The involvement of candidate genes was examined by oligo- and plasmid-mediated RNA interference. Biological functions of several of these genes were examined using in vitro assays for invasion, angiogenesis, apoptosis, cell viability, and matrix digestion. Angiogenesis in vivo was measured by CD-31 immunohistochemistry and microvessel density scoring. RESULTS: LA enhanced the plasminogen activator inhibitor 1 (PAI-1) mRNA and protein expression, which are controlled by PAI-1 mRNA-binding protein. LA-stimulated invasion depended on PAI-1. LA also enhanced angiogenesis by suppression of angiostatin, also through PAI-1. LA did not alter cell growth in culture, but increased dietary LA-enhanced tumour growth in an animal model. CONCLUSION: Our findings suggest that dietary LA impacts multiple steps in cancer invasion and angiogenesis, and that reducing LA in the diet may help slow cancer progression.

Plasma levels of angiostatin and endostatin remain unchanged for the first 3 weeks after colorectal cancer surgery.

INTRODUCTION: Angiostatin and endostatin are endogenous inhibitors of angiogenesis with anticancer effects. After minimally invasive colorectal resection (MICR), blood levels of the proangiogenic factors vascular endothelial growth factor (VEGF) and angiopoetin 2 (Ang-2) are elevated for 2-4 weeks. Also, postoperative human plasma from weeks 2 and 3 after MICR has been shown to stimulate endothelial cell proliferation and migration, which are critical to angiogenesis. This proangiogenic state may stimulate tumor growth early after MICR. Surgery's impact on angiostatin and endostatin is unknown. This study's purpose is to determine perioperative plasma levels of these two proteins in colorectal cancer (CRC) patients undergoing MICR. METHODS: Endostatin levels were assessed in 34 CRC patients and angiostatin levels in 30 CRC patients. Blood samples were taken preoperatively and on postoperative day (POD) 1 and 3 in all patients; in a subset, samples were taken between POD 7 and 20. The late samples were bundled into 7-day blocks (POD 7-13, POD 14-20) and considered as single time points. Angiostatin and endostatin plasma levels were determined via enzyme-linked immunosorbent assay (ELISA) in duplicate. Wilcoxon signed-rank test and Student's t test were used to analyze endostatin and angiostatin data, respectively. Significance was set at P<0.0125 (after Bonferroni correction). RESULTS: There was a significant decrease in median plasma endostatin levels on POD 1, which returned to the preoperative level by POD 3. There was no significant difference between pre- and postoperative plasma angiostatin levels. CONCLUSIONS: MICR has a very transient impact on plasma levels of endostatin and no impact on angiostatin during the first 21 days following surgery. Thus, angiostatin and endostatin do not likely contribute to or inhibit the persistent proangiogenic changes noted after MICR.

Urinary angiostatin levels are elevated in patients with epithelial ovarian cancer.

OBJECTIVE: The poor prognosis associated with epithelial ovarian cancer (EOC) is due to the lack of overt early symptoms and the absence of reliable diagnostic screening methods. Since many tumors over express angiogenic regulators, the purpose of this study was to determine whether elevated levels of the angiogenic or angiostatic molecules vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), endostatin (ES), and angiostatin (AS) were elevated in plasma and urine from patients with EOC. METHODS: VEGF, HGF, ES and AS were assayed by ELISA in samples from pilot cohort consisting of healthy women (N=48; pre-menopausal N=23, post-menopausal N=25), women with benign gynecological disease (N=54), patients with primary peritoneal cancer (PP) (N=2) and EOC (N=35). Wherever possible, parallel serum samples were measured for CA125 levels by ELISA. RESULTS: AS was the angioregulator that independently discriminated EOC patients from healthy individuals. Levels of urinary AS (uAS) from healthy individuals or women with benign gynecological disease averaged 21.4 ng/mL+/-3.7 and 41.5 ng/mL+/-8.8, respectively. In contrast, uAS averaged 115 ng/mL+/-39.2 and 276 ng/mL+/-45.8 from women with Stage I (N=6) and late stage (N=31) EOC, respectively. Furthermore, uAS was elevated in EOC patients regardless of tumor grade, stage, size, histological subtype, creatinine levels, menopausal status, or patient age, but appeared to complement CA125 measurements. CONCLUSIONS: Levels of AS are elevated in the urine of patients with EOC and may be of diagnostic and/or prognostic clinical importance. Further studies of uAS as a biomarker for EOC alone or in combination with other markers are warranted.

Levels of angiogenic factors in patients with multiple myeloma correlate with treatment response.

Angiogenesis plays a significant role in the pathogenesis of multiple myeloma (MM). We have measured concentrations of angiogenesis activators, including vascular endothelial growth factor (VEGF), basic fibroblast growth factor, and hepatocyte growth factor (HGF), and inhibitors, including endostatin, thrombospondin-1 (TSP-1), and angiostatin in the peripheral and bone marrow blood of MM patients at diagnosis and after high-dose chemotherapy. We have analyzed 96 patients with secretory MM. Serial measurements of angiogenesis factors/inhibitors were analyzed in the plasma by subgroups based on the best treatment response. Concentrations of angiogenic factors were determined in the peripheral blood and bone marrow plasma. There were significant decreases of VEGF and HGF levels and a significant increase in TSP-1 concentrations in the bone marrow plasma of patients who achieved complete or very good partial response in contrast to those who had partial or no response. VEGF and HGF levels decrease but those of TSP-1 increase after successful treatment for MM, indicating a reduction in the rate of angiogenesis.

Pretreatment hepatocyte growth factor and thrombospondin-1 levels predict response to high-dose chemotherapy for multiple myeloma.

UNLABELLED: Our aim was to establish whether the pretreatment levels of angiogenesis activators and inhibitors can be used to predict clinical responses to treatment that included high-dose chemotherapy with peripheral stem cell support.
We analyzed samples and treatment outcomes of 96 patients with MM enrolled in the CMG 2002 randomized clinical trial and treated with induction chemotherapy and high-dose chemotherapy with stem cell support. Concentrations of vascular endothelial growth factor (VEGF), hepatocytar growth factor (HGF), basic fibroblastic growth factor (bFGF), thrombospondin-1 (TSP-1), endostatin, and angiostatin were measured in the peripheral blood plasma and in the bone marrow plasma at diagnosis.
Pretreatment HGF concentrations in the peripheral blood plasma as well as in the bone marrow plasma of patients who achieved complete or very good partial response were significantly lower than those in patients who had partial or worse response. Patients with complete or very good partial response had higher TSP-1 levels in the bone marrow plasma than the partial or insufficient response subgroups. There were no correlations between the pretreatment levels of VEGF, bFGF, endostatin, or angiostatin and the treatment response.
Pretreatment concentrations of HGF and TSP-1 were predictive factors for treatment response. Patients with low angiogenesis rate as determined by the relative HGF and TSP-1 concentrations were more likely to achieve complete or very good partial response after high-dose chemotherapy. KEYWORDS: Angiogenesis, cytokines, high-dose chemotherapy, multiple myeloma, therapeutic response.

Pathological role of angiostatin in heart failure: an endogenous inhibitor of mesenchymal stem-cell activation.

OBJECTIVE: Recently, a clinical trial was initiated to evaluate the efficacy of transendocardial transplantation of autologous bone marrow-derived mesenchymal stem cells (MSC) for the treatment of heart failure (HF). Because some HF patient-derived sera did not induce proliferation of autologous MSC, the present study aimed to elucidate humoral factors in sera that attenuate MSC activation and to investigate the role of these humoral factors in the pathogenesis of HF. METHODS AND RESULTS: Inhibitory effects present in serum were analysed by culturing human MSC with sera from 10 HF patients (FS <25%, BNP >100 pg/ml) and four healthy control subjects. Among the patients, two sera from HF patients showed significant inhibitory activity on MSC proliferation. Protein array and ELISA analysis revealed that these sera contained high levels of angiostatin as well as the active form of matrix metalloproteinase (MMP)-9, which generates angiostatin. Angiostatin significantly inhibited the proliferation and migration of cultured human MSC and increased their apoptosis in a dose-dependent manner. In a rat HF model, serum levels of angiostatin and MMPs increased, but treatment with an MMP inhibitor suppressed these increases. CONCLUSIONS: The results suggest that angiostatin, which can attenuate the activity of MSC, might play a role in the progression of HF.

[Relationship between changes of serum concentrations of antiangiogenic factors and disease progression in patients of pancreatic carcinoma].

OBJECTIVE: To investigate the relationship between TSP-1, Angiostatin and Endostatin serum concentrations and progression of pancreatic adenocarcinoma. METHODS: Fifty-six patients with suspected pancreatic cancer were enrolled in the study and divided into resectable group (n = 32) and unresectable group (n = 24) according to evaluation and staging with dual phase helical CT. Histopathologic examinations included postoperative final pathology and preoperative fine needle biopsies. Peripheral blood concentrations of antiangiogenic factors Angiostatin, Endostatin and TSP-1 were detected by using ELISA methods, selecting samples of health people as a control. RESULTS: Serum concentrations of antiangiogenic factors in pancreatic cancer group were significantly higher than those in health group (P < 0.01). Serum concentrations of Endostatin, Angiostatin and TSP-1 were significantly increased in unresectable group, and highly expressed in patients whom tumor sizes were greater than 2 cm and tumor invaded peripancreatic great vessels (P < 0.05). After operation, serum concentrations of Endostatin, Angiostatin and TSP-1 significantly decreased (P < 0.05). There were no significant difference between I, II stage group and III, IV group. CONCLUSIONS: Detection of serum concentrations of antiangiogenic factors may be used to evaluate the resectability of pancreatic cancer and may play important roles in growth, invasion and metastasis of pancreatic cancer.

Expression of angiostatin and its related factors in the plasma of newborn pigs with hypoxia and reoxygenation.

Little is known about angiostatin and its related factors in the hypoxia-reoxygenation of neonates. In this study we compared the effect of 21% and 100% reoxygenation on temporal changes in the plasma level of these factors in newborn piglets subjected to hypoxia. Newborn piglets were subjected to 2 h hypoxia followed by 1 h of reoxygenation with either 21% or 100% oxygen and observed for 4 days. On day 4 of recovery in 100% hypoxic-reoxygenated group, there were increases in total angiostatin, plasminogen/plasmin and MMP-2 levels, and decreases in VEGF levels (vs. respective baseline levels, all P <0.001), whereas no significant temporal changes were found in the 21% hypoxic-reoxygenated and sham-operated groups. Angiostatin levels correlated positively with the levels of MMP-2 and HIF-1alpha and negatively with VEGF levels in 100% hypoxic-reoxygenated group (all P <0.05). In comparison to 21% oxygen, neonatal resuscitation with 100% oxygen was found to increase the levels anti-angiogenic factors.

Antiangiogenic therapy enhances the efficacy of transcatheter arterial embolization for hepatocellular carcinomas.

Transcatheter arterial embolization (TAE) is a well-established technique for unresectable hepatic malignancies. However, TAE can temporally halt the growth of hepatic tumors by blocking their arterial supply, but often tumors rapidly develop collateral blood vessels via angiogenesis. We have previously demonstrated that intraportal delivery of adeno-associated viral particles expressing angiostatin leads to long-term expression of angiostatin capable of inhibiting angiogenesis and suppressing the outgrowth of tumors in the liver. Thus, we hypothesize that adeno-associated virus (AAV)-mediated antiangiogenic therapy could enhance the efficacy of TAE to combat liver cancers. To achieve this objective, we engineered a recombinant AAV vector encoding rat angiostatin. Intraportal delivery of this vector led to long term and stable transgenic expression of angiostatin locally in rat hepatocytes and suppressed the growth of CBRH7919 hepatocellular carcinomas established in rat livers by inhibiting formation of neovessels. Although TAE therapy led to necrosis of liver tumors and suppressed their growth, the neovessels of tumors were rapidly reformed 3 weeks after TAE. However, intraportal injection of AAV-angiostatin inhibited the angiogenesis stimulated by TAE, synergized with TAE in suppressing growth of tumors established in livers and prolonged the survival of rats. In conclusion, these encouraging results warrant future investigation of the use of antiangiogenic therapy for enhancing the therapeutic efficacy of TAE to treat unresectable liver cancers.