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Heart (British Cardiac Society) Feb 2009
Topics: Angiostatins; Cardiomyopathy, Dilated; Heart Failure; Humans; Myocardial Ischemia; Myocardium
PubMed: 19095713
DOI: 10.1136/hrt.2008.154013 -
World Journal of Gastroenterology Aug 2005To observe the biologic behavior of pancreatic cancer cells in vitro and in vivo, and to explore the potential value of angiostatin gene therapy for pancreatic cancer.
AIM
To observe the biologic behavior of pancreatic cancer cells in vitro and in vivo, and to explore the potential value of angiostatin gene therapy for pancreatic cancer.
METHODS
The recombinant vector pcDNA3.1(+)-angiostatin was transfected into human pancreatic cancer cells PC-3 with Lipofectamine 2000, and paralleled with the vector and mock control. Angiostatin transcription and protein expression were determined by immunofluorescence and Western blot. The stable cell line was selected by G418. The supernatant was collected to treat endothelial cells. Cell proliferation and growth in vitro were observed under microscope. Cell growth curves were plotted. The troms-fected or untroms-fected cells overexpressing angiostatin vector were implanted subcutaneously into nude mice. The size of tumors was measured, and microvessel density count (MVD) in tumor tissues was assessed by immunohistochemistry with primary anti-CD34 antibody.
RESULTS
After transfected into PC-3 with Lipofectamine 2000 and selected by G418, macroscopic resistant cell clones were formed in the experimental group transfected with pcDNA 3.1(+)-angiostatin and vector control. But untreated cells died in the mock control. Angiostatin protein expression was detected in the experimental group by immunofluorescence and Western-blot. Cell proliferation and growth in vitro in the three groups were observed respectively under microscope. After treatment with supernatant, significant differences were observed in endothelial cell (ECV-304) growth in vitro. The cell proliferation and growth were inhibited. In nude mice model, markedly inhibited tumorigenesis and slowed tumor expansion were observed in the experimental group as compared to controls, which was parallel to the decreased microvessel density in and around tumor tissue.
CONCLUSION
Angiostatin does not directly inhibit human pancreatic cancer cell proliferation and growth in vitro, but it inhibits endothelial cell growth in vitro. It exerts the anti-tumor functions through antiangiogenesis in a paracrine way in vivo.
Topics: Angiostatins; Animals; Cell Division; Cell Line, Tumor; Endothelial Cells; Genetic Therapy; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Pancreatic Neoplasms; Xenograft Model Antitumor Assays
PubMed: 16124051
DOI: 10.3748/wjg.v11.i32.4992 -
Thrombosis and Haemostasis Mar 2002What is angiostatin? In 1994, Folkman and colleagues published a landmark paper describing anti-tumor effects in mice with a purified fragment of plasminogen they named... (Review)
Review
What is angiostatin? In 1994, Folkman and colleagues published a landmark paper describing anti-tumor effects in mice with a purified fragment of plasminogen they named angiostatin (1). Although many papers have been published describing activities of cryptic polypeptides derived from plasminogen fragments, this was the first report which associated plasminogen kringles 1-4 as a suppressor of metastasis development. This review will describe what is known about the mechanism of action of angiostatin from the current literature.
Topics: Angiogenesis Inhibitors; Angiostatins; Animals; Antineoplastic Agents; Binding Sites; Humans; Mitochondrial Proton-Translocating ATPases; Peptide Fragments; Plasminogen
PubMed: 11916069
DOI: No ID Found -
Veterinary Ophthalmology 2007Angiogenesis is tightly controlled in the ocular tissues of domestic animals but its mechanisms are not fully understood. This is largely because of insufficient data on...
PURPOSE
Angiogenesis is tightly controlled in the ocular tissues of domestic animals but its mechanisms are not fully understood. This is largely because of insufficient data on the expression of molecules that impact angiogenesis. Because angiostatin and one of its receptors integrin alphavbeta3 inhibit and promote angiogenesis, respectively, we hypothesized that the normal retina and cornea of domestic animals would express angiostatin but not integrin alphavbeta3.
PROCEDURE
Normal eyes of the cat, cow, dog, horse, pig and rat were evaluated for angiostatin and integrin alphavbeta3 by light and electron immunocytochemistry and estern blots.
RESULTS
Angiostatin was detected in the corneal epithelium of the cat, dog, horse, pig and rat, but was not found in cow corneal epithelium. Angiostatin was localized in the nerve fiber layer, ganglion cell layer, inner and outer plexiform layers, and the photoreceptor layer of the cat, cow, dog and rat. Horse and pig retinas showed additional staining in the matrix of the inner nuclear layer. Immunogold electron microscopy further confirmed angiostatin in cat retina. Western blots showed angiostatin in corneal and retinal homogenates. Integrin alphavbeta3 was absent in cornea and retina of all the species studied.
CONCLUSION
These data show that angiostatin, an inhibitor of angiogenesis, is present while integrin alphavbeta3, which promotes angiogenesis, is absent in normal cornea and retina of the domestic animals in this study with the exception being angiostatin absence in cow corneal epithelium. Therefore, angiostatin may contribute to the anti-angiogenic environment in the normal domestic animal eye while its absence in the cow may contribute to greater propensity for corneal vascularization. Because integrin alphavbeta3 is one of the receptors for angiostatin, its absence may prevent angiostatin from killing normal retinal and corneal cells.
Topics: Angiostatins; Animals; Blotting, Western; Cats; Cattle; Cornea; Dogs; Horses; Immunohistochemistry; Integrin alphaVbeta3; Mice; Retina; Species Specificity; Swine
PubMed: 17760712
DOI: 10.1111/j.1463-5224.2007.00560.x -
Progress in Molecular and Subcellular... 1998
Review
Topics: Angiostatins; Animals; Collagen; Endostatins; Humans; Neovascularization, Physiologic; Peptide Fragments; Plasminogen
PubMed: 9928530
DOI: 10.1007/978-3-642-72149-6_8 -
Endothelium : Journal of Endothelial... 2002Angiostatin inhibits angiogenesis by binding to endothelial cells (ECs) lining the vasculature of growing tumors. These cells are in a dynamic state during angiogenesis...
Angiostatin inhibits angiogenesis by binding to endothelial cells (ECs) lining the vasculature of growing tumors. These cells are in a dynamic state during angiogenesis and are thus not firmly attached to the extracellular matrix. This makes them more vulnerable to anoikis, a process resulting in cell death initiated by or promoted by loss of attachment. Another potential source of EC vulnerability during tumor angiogenesis is that tumor extracellular pH is typically lower than in normal tissues. This presents an additional challenge to ECs in terms of maintaining ionic homeostasis. We report here that the lethality of angiostatin is significantly enhanced both by reduced matrix attachment during exposure and lowered extracellular pH (pH(e)). Another effect of angiostatin at reduced pH(e) is a decreased intracellular pH (pH(i)). These effects were observed in three model systems: aortic ring sprouts, ECs during tube formation, and ECs in a scratch/migration assay. In these three dynamic assays, angiostatin-induced cell death and intracellular acidification were clearly seen when pH(e) was reduced to 6.7. The intracellular acidification was far greater than that induced by pH(e) reduction alone. In contrast, the effect of angiostatin on pH(i) and on viability were not observed in a subconfluent monolayer in which the cells were allowed to attach to substrate for 48 h prior to exposure to angiostatin. These data suggest that low pH(e) and reduced adhesion to matrix play a role in the specificity of angiostatin for tumor neovasculature in contrast to wound healing and other normal angiogenic processes. The results also implicate roles for both pH(e) and pH(i) regulation in the mechanism of angiostatin action.
Topics: Acidosis; Angiostatins; Animals; Anoikis; Cells, Cultured; Endothelium, Vascular; Guanidines; Humans; Hydrogen-Ion Concentration; Intracellular Fluid; Neoplasms; Peptide Fragments; Plasminogen; Rats; Sulfones
PubMed: 12380645
DOI: 10.1080/10623320213633 -
Molecular Vision May 2006Our previous experiments have shown that low dose angiostatin results in decreased hepatic micrometastasis in a mouse model of uveal melanoma. The purpose of these...
Angiostatin decreases cell migration and vascular endothelium growth factor (VEGF) to pigment epithelium derived factor (PEDF) RNA ratio in vitro and in a murine ocular melanoma model.
PURPOSE
Our previous experiments have shown that low dose angiostatin results in decreased hepatic micrometastasis in a mouse model of uveal melanoma. The purpose of these experiments is to evaluate the effect of angiostatin on in vitro migration of melanoma cells and to explore the in vivo mechanism of angiostatin in our model.
METHODS
For in vitro studies, quantitative RT-PCR was used to detect VEGF and PEDF mRNA in mouse B16LS9 melanoma cells and Mel290 human uveal melanoma cells with or without supplemental 0.1 mug/ml murine or human recombinant angiostatin. A wound healing assay was used to measure cellular migration in these two groups of cells. For the in vivo mechanism, aliquots of tissue culture B16LS9 cells treated with or without 0.1 mug/ml murine angiostatin were heterotopically inoculated into the posterior compartments of the right eyes of C57BL/6 mice. Frozen hepatic tissue was prepared and stained with hematoxylin using an RNase-free technique. Hepatic micrometastatic uveal melanoma cells were obtained by laser capture microdissection (LCM). Levels of VEGF and PEDF mRNA were detected by real time RT-PCR in the hepatic micrometastases.
RESULTS
After in vitro treatment of the cell lines with angiostatin, the ratio of VEGF/PEDF mRNA significantly decreased in the B16LS9 (0.88+/-0.11 [mean+/-standard deviation] versus 2.70+/-0.15 in the control group; p=0.00006) and Mel290 (0.12+/-0.02 versus 0.68+/-0.04 in the control group; p=0.00346). However, the absolute VEGF mRNA and PEDF mRNA did not significantly change (p>0.08 for both cell lines). The migration assay showed significantly decreased migration at 24 h and 48 h after angiostatin treatment for both B16LS9 (p<0.01) and Mel290 (p<0.01) cell lines. For the in vivo experiments, pretreatment with angiostatin resulted in a decreased VEGF/PEDF mRNA ratio in B16LS9 cells compared to controls (0.0274+/-0.0070 versus 0.1726+/-0.0313; p=0.0014). Additionally, there was significantly increased PEDF mRNA (2.14+/-0.12 versus 0.30+/-0.05 in the control group; p=0.00002) in the liver metastases after pretreatment with angiostatin.
CONCLUSIONS
Angiostatin inhibits the migration of melanoma cells in vitro. Angiostatin significantly decreases the ratio of VEGF/PEDF mRNA level in vitro and in hepatic micrometastatic melanoma cells. Angiostatin increases PEDF mRNA in melanoma metastases.
Topics: Angiostatins; Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Movement; Eye Neoplasms; Eye Proteins; Female; Humans; Liver Neoplasms; Melanoma; Mice; Mice, Inbred BALB C; Nerve Growth Factors; RNA, Messenger; Recombinant Proteins; Serpins; Vascular Endothelial Growth Factor A
PubMed: 16735992
DOI: No ID Found -
Circulation May 2002The in vivo mechanism by which inhibition of NO synthase impairs ischemia-induced coronary vascular growth is unknown. We hypothesized that production of the growth...
BACKGROUND
The in vivo mechanism by which inhibition of NO synthase impairs ischemia-induced coronary vascular growth is unknown. We hypothesized that production of the growth inhibitor angiostatin increases during decreased NO production, blunting angiogenesis and collateral growth.
METHODS AND RESULTS
Measurements were made in myocardial tissue or interstitial fluid (MIF) from dogs undergoing repetitive coronary occlusions under control conditions or during antagonism of NO synthase (N(G)-nitro-L-arginine methyl ester [L-NAME]) for 7, 14, or 21 days. A sham group was instrumented identically but received no occlusions. In controls, capillary density in the ischemic zone increased initially but returned to baseline at the later times. In the L-NAME group, capillary density was lower at 7 days compared with that of controls. MIF from control dogs induced in vitro endothelial tube formation and cell proliferation, significantly greater than that from the L-NAME group. MIF from shams did not stimulate tube formation. In controls or shams, tube formation or cell proliferation did not change after administration of antiangiostatin, but this antibody restored the responses to control levels in the L-NAME group. Angiostatin expression in MIF was increased in the L-NAME group compared with controls and shams. The activities of tissue matrix metalloproteinases (MMPs) MMP-2 and MMP-9, which generate angiostatin, were increased in the L-NAME group.
CONCLUSIONS
Inhibition of NO synthase increased expression of angiostatin and activities of MMP-2 and MMP-9. Our findings indicate that angiostatin inhibits coronary angiogenesis during compromised NO production and may underscore the impairment of coronary angiogenesis during endothelial dysfunction.
Topics: Angiogenesis Inhibitors; Angiostatins; Animals; Capillaries; Cell Division; Cells, Cultured; Collateral Circulation; Coronary Circulation; Dogs; Endothelium, Vascular; Extracellular Space; Female; Humans; Kinetics; Male; Matrix Metalloproteinases; Myocardial Ischemia; NG-Nitroarginine Methyl Ester; Neovascularization, Physiologic; Nitric Oxide; Nitric Oxide Synthase; Peptide Fragments; Plasminogen
PubMed: 11994253
DOI: 10.1161/01.cir.0000015856.84385.e9 -
Cellular and Molecular Biology... Feb 2022Gallbladder cancer is one of the gastrointestinal tumors with an extremely poor prognosis. Its incidence rate is gradually increasing worldwide, and the rate of radical...
Gallbladder cancer is one of the gastrointestinal tumors with an extremely poor prognosis. Its incidence rate is gradually increasing worldwide, and the rate of radical resection surgery is extremely low. Not sensitive to radiotherapy and chemotherapy, with a very poor prognosis. This study aimed to investigate whether the recombinant mouse angiostatin gene transfected anti-angiogenic gallbladder cancer cells can express angiostatin protein with the activity of inhibiting the growth of vascular endothelial cells and the inhibitory effect on the growth of gallbladder cancer. The recombinant mouse angiostatin gene eukaryotic expression plasmid was transfected into the gallbladder cancer cell line by applying liposome LIPOFECTAMINE 2000, and its activity was detected by vascular endothelial cell proliferation analysis. The results show that angiostatin can inhibit the growth of transplanted gallbladder cancer, and as the number of injections increases, the inhibition rate of gallbladder cancer growth also increases. At the end of the experiment, the total inhibition rate of gallbladder cancer growth reached 95% 5%, 20%, 30%, 40% gradually increase. Therefore, angiostatin has potential clinical application value in gene therapy of gallbladder cancer.
Topics: Angiostatins; Animals; Cell Proliferation; Endothelial Cells; Gallbladder Neoplasms; Genetic Therapy; Mice; Peptide Fragments
PubMed: 35818206
DOI: 10.14715/cmb/2021.67.6.16 -
Molecular Cell Biology Research... May 2000Angiostatin is an inhibitor of tumor angiogenesis that induces regression of experimental tumors and enhances the antitumor effects of radiation therapy. We report that...
Angiostatin is an inhibitor of tumor angiogenesis that induces regression of experimental tumors and enhances the antitumor effects of radiation therapy. We report that the cytotoxic effects of angiostatin are restricted to the proliferating endothelial cell population. In addition, angiostatin and ionizing radiation (IR) interact by inducing death of dividing endothelial cells. We also show that angiostatin and IR interact to inhibit endothelial cell migration. These findings demonstrate that angiostatin targets the proliferating tumor vasculature and provide a mechanistic basis for the cytotoxic interaction of angiostatin and IR.
Topics: Angiogenesis Inhibitors; Angiostatins; Animals; Antineoplastic Agents; Aorta; Cattle; Cell Death; Cell Division; Cell Migration Inhibition; Cells, Cultured; Endothelium, Vascular; Humans; Mitosis; Peptide Fragments; Plasminogen; Radiation, Ionizing; Recombinant Proteins; Umbilical Veins
PubMed: 10964751
DOI: 10.1006/mcbr.2000.0222