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Biological & Pharmaceutical Bulletin Mar 2022Anti-angiogenic gene therapy is a promising strategy in treating cancer. Endostatin and angiostatin are widely used in tumor anti-angiogenesis therapy. Our previous...
Anti-angiogenic gene therapy is a promising strategy in treating cancer. Endostatin and angiostatin are widely used in tumor anti-angiogenesis therapy. Our previous studies have shown that the BDS-hEA, a baculovirus long-term expressing the fusion protein of human endostatin and angiostatin, has a favorable effect in inhibiting the growth and angiogenesis of hepatocellular carcinoma. The purpose of this study was to further investigate its synergistic antitumor efficiency in combination with low-dose chemotherapeutic gemcitabine (GEM) on the subcutaneous hepatocellular carcinoma xenograft model in nude mice. The results showed that the combined group significantly inhibited (p < 0.05 or p < 0.01 or p < 0.001) the growth of tumor weight and volume, reduced the expression of ki67 (cell proliferation marker), CD31 (angiogenic marker) and Matrix metalloproteinase 9 (MMP-9, tumor invasion and metastasis marker) and increased the apoptosis of tumor cells compared with the monotherapy and control groups, respectively. Synergistic index results showed that BDS-hEA combined with GEM had a synergistic effect in inhibiting tumor volume, proliferation, microvessel density, metastasis and promoting tumor apoptosis. Furthermore, there were no metastatic nodules and obvious pathological changes in liver tissue of the combined group, and the serum liver function indicators aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (T-BIL), alkaline phosphatase (ALP) and glutamyl transpeptidase (GGT) were significantly reduced (p < 0.05 or p < 0.01 or p < 0.001) in the BDS-hEA or GEM groups compared with the control group. Notably, the combined therapy showed lower levels of liver function indicators than the GEM group. These data support the view that the combination of BDS-hEA and GEM has a synergistic anti-tumor properties and can reduce the damage of liver to certain extent.
Topics: Angiogenesis Inhibitors; Angiostatins; Animals; Baculoviridae; Carcinoma, Hepatocellular; Deoxycytidine; Endostatins; Humans; Liver Neoplasms; Mice; Mice, Nude; Gemcitabine
PubMed: 34937830
DOI: 10.1248/bpb.b21-00857 -
Biochemical and Biophysical Research... Jun 2002Angiostatin is a plasminogen-derived anti-angiogenic factor composed of its first four kringle structures. This molecule is generated by proteolytic cleavage of...
Angiostatin is a plasminogen-derived anti-angiogenic factor composed of its first four kringle structures. This molecule is generated by proteolytic cleavage of plasminogen by some proteolytic enzymes in vitro. Since venoms of viper snakes are a rich source of both serine- and metalloproteinase, we hypothesized that angiostatin-like polypeptides could be generated during the envenomation after snake bites and play a pathophysiological role in the local tissue damage and regeneration. Our results showed that crude venoms from several species of Bothrops snakes were able to generate angiostatin-like polypeptides and purified metalloproteinases but not serine proteinases from Bothrops jararaca and Bothrops moojeni venoms were responsible for their generation in vitro. The putative plasminogen cleavage sites by the crude venoms and purified proteinases were determined by N-terminal amino acid sequencing of the angiostatin-like molecules. Angiostatin-like peptides derived from human plasminogen digestion by jararhagin, a metalloproteinase isolated from B. jararaca venom, inhibited endothelial cell proliferation in vitro. These results indicate that angiostatin-like molecules can be generated upon snakebite envenomations and may account for the poor and incomplete regenerative response observed in the damaged tissue.
Topics: Angiostatins; Animals; Base Sequence; Bothrops; Cell Division; Cells, Cultured; Electrophoresis, Polyacrylamide Gel; Endothelium, Vascular; Humans; Metalloendopeptidases; Molecular Sequence Data; Peptide Fragments; Peptides; Plasminogen; Protein Conformation; Protein Structure, Tertiary; Snake Venoms; Umbilical Veins
PubMed: 12061789
DOI: 10.1016/S0006-291X(02)00567-3 -
Journal of the American Society of... Feb 2006Angiostatin is a proteolytic fragment of plasminogen and a potent angiogenic inhibitor. Previous studies have shown that angiostatin inhibits retinal neovascularization...
Angiostatin is a proteolytic fragment of plasminogen and a potent angiogenic inhibitor. Previous studies have shown that angiostatin inhibits retinal neovascularization and reduces retinal vascular permeability in diabetic retinopathy. Here, it is reported for the first time that angiostatin is also implicated in diabetic nephropathy (DN). Angiostatin levels are dramatically decreased in the kidney of streptozotocin-induced diabetic rats. Consistently, diabetic kidneys also showed decreased expression and proteolytic activities of matrix metalloproteinase-2, an enzyme that releases angiostatin from plasminogen. Adenovirus-mediated delivery of angiostatin significantly alleviated albuminuria and attenuated the glomerular hypertrophy in diabetic rats. Moreover, angiostatin treatment downregulated the expression of vascular endothelial growth factor and TGF-beta1, two major pathogenic factors of DN, in diabetic kidneys. In cultured human mesangial cells, angiostatin blocked the overexpression of vascular endothelial growth factor and TGF-beta1 that were induced by high glucose while increasing the levels of pigment epithelium-derived factor, an endogenous inhibitor of DN. Moreover, angiostatin effectively inhibited the high-glucose-and TGF-beta1-induced overproduction of proinflammatory factors and extracellular matrix proteins via blockade of the Smad signaling pathway. These findings suggest that the decrease of angiostatin levels in diabetic kidney may contribute to the pathologic changes such as inflammation and fibrosis in DN. Therefore, angiostatin has therapeutic potential in DN as a result of its anti-inflammatory and antifibrosis activities.
Topics: Angiostatins; Animals; Cell Culture Techniques; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Humans; Intercellular Adhesion Molecule-1; Matrix Metalloproteinase 2; Mesangial Cells; RNA, Messenger; Rats; Rats, Inbred BN; Transforming Growth Factor beta; Transforming Growth Factor beta1; Vascular Endothelial Growth Factor A
PubMed: 16394111
DOI: 10.1681/ASN.2005020217 -
The Journal of Laboratory and Clinical... Dec 1999
Comparative Study Review
Topics: Angiostatins; Animals; Antineoplastic Agents; Glycosylation; Humans; Mice; Molecular Structure; Neoplasms, Experimental; Peptide Fragments; Plasminogen; Polysaccharides
PubMed: 10595781
DOI: 10.1016/s0022-2143(99)90093-8 -
Anticancer Research 1999Angiostatin, a family of fragments originating from the NH2-terminal portion of plasminogen, has been described as a potent inhibitor of angiogenesis. In order to...
Angiostatin, a family of fragments originating from the NH2-terminal portion of plasminogen, has been described as a potent inhibitor of angiogenesis. In order to examine to what extent angiostatin can be detected in cancer patients, urine was collected from 117 patients with different types of malignancies and subjected to Western blot analysis, utilizing antibodies raised against "kringles" 1-3 in plasminogen. A heterogeneous mixture of fragments was observed, with patterns that also varied between patients. Angiostatin fragments were quantified by densitometric scanning. The concentrations were 27 +/- 75 (SD) micrograms L-1 (range, 1-565 micrograms L-1) in urine from cancer patients, as compared to 3 +/- 2 (SD) micrograms L-1 (range, 1-10 micrograms L-1) in urine from healthy individuals. Thirty-three patients (28%) had elevated levels using a cut off level at 15 micrograms L-1 (clearly above the highest level obtained among control subjects). NH2-terminal amino acid sequence analysis of purified angiostatin fragments from one patient showed a heterogeneous pattern, but were consistent with the region between the preactivation peptide in plasminogen and "kringle" 1, as expected. Several of the patients with urinary angiostatin showed signs of poor kidney function. We conclude that angiostatin can be detected in urine from cancer patients, but at present, the clinical significance of this finding is unclear.
Topics: Albuminuria; Alpha-Globulins; Amino Acid Sequence; Angiostatins; Blotting, Western; Case-Control Studies; Densitometry; Head and Neck Neoplasms; Humans; Kidney Neoplasms; Kringles; Luminescent Measurements; Lung Neoplasms; Mesothelioma; Molecular Sequence Data; Neoplasms; Peptide Fragments; Plasminogen; Prognosis; Sarcoma
PubMed: 10629628
DOI: No ID Found -
FASEB Journal : Official Publication of... Dec 2007In light of the involvement of tumor-associated macrophages (TAM) in the promotion of tumor growth and metastasis, strategies to prevent TAM recruitment within the tumor...
In light of the involvement of tumor-associated macrophages (TAM) in the promotion of tumor growth and metastasis, strategies to prevent TAM recruitment within the tumor microenvironment are currently under investigation. The recent observation that angiostatin reduces macrophage infiltration in an atherosclerosis model prompted our laboratory to further explore the use of human plasminogen angiostatin (hK1-3) protein as a macrophage modulatory agent. We demonstrate that hK1-3 blocks migration of murine peritoneal macrophages (91% decrease, P<0.00005) and human monocytes (85% decrease, P<0.05) in vitro. Cell viability of hK1-3-treated cells is not affected, as determined by fluorochrome-labeled inhibitors of caspase-propidium iodide (FLICA/PI) flow cytometry analysis. Furthermore, confocal microscopy of phalloidin-stained cells reveals that hK1-3 leads to disruption of actin filopodia/lamellipodia in human monocytes and induces distinct podosome accumulation in mature differentiated macrophages. Paradoxically, we observed a 3.5-fold increase in secretion and a 3- to 5.5-fold increase in gelatinolytic activity of macrophage-produced matrix metalloproteinase-9, which we suggest is a cellular response to compensate for the dominant static effect of hK1-3 on actin. We also demonstrate that hK1-3 induces the phosphorylation of extracellular signal-regulated kinase (ERK1/2) in human monocytes. hK1-3-mediated macrophage immobilization has the potential to be exploited therapeutically in pathological conditions associated with cellular hypoxia, such as cancer and atherosclerosis.
Topics: Actins; Angiostatins; Animals; Cell Migration Inhibition; Cells, Cultured; Cytoskeleton; Humans; Kringles; Macrophages, Peritoneal; Mice; Mice, Inbred C57BL; Monocytes; Neoplasms, Experimental; Peptide Fragments
PubMed: 17622568
DOI: 10.1096/fj.07-8158com -
American Journal of Physiology. Heart... May 2005Angiostatin, an inhibitor of tumor angiogenesis, is produced by the actions of matrix metalloproteinases (MMP) on plasminogen. Recently, we reported that angiostatin...
Angiostatin, an inhibitor of tumor angiogenesis, is produced by the actions of matrix metalloproteinases (MMP) on plasminogen. Recently, we reported that angiostatin levels are increased in a model of inadequate coronary collateral growth and angiogenesis in response to ischemia, despite high levels of vascular endothelial growth factor (VEGF). We hypothesized that angiostatin levels are negatively associated with collateral formation in patients. Coronary angiograms from 37 patients undergoing coronary bypass surgery were evaluated for the absence of angiographically visible collaterals (Rentrop scores of 0) or the presence of Rentrop classification grade 3 (well developed) collaterals. Pericardial fluid was obtained from each patient during the bypass procedure, and the sample was analyzed for angiostatin, plasminogen, and VEGF (Western analysis) and for combined activities of MMP-2 and MMP-9 (zymographic analysis). In patients with no collaterals, angiostatin level was greater compared with that in patients with well-developed collaterals (3.1 +/- 0.2 vs. 2.3 +/- 0.1 optical density units, P < 0.05). Neither MMP activities nor VEGF levels were different between the two groups of patients. The higher levels of angiostatin in patients with no visible collaterals were reflective of a higher concentration of plasmin/plasminogen (6.2 +/- 0.7 vs. 4.2 +/- 0.5 optical density units, P < 0.05) compared with those in patients with well-developed collateral vessels. Our results support the concept that the growth inhibitor angiostatin may have a negative impact on coronary collateral growth in patients. Perhaps therapies attempting to provoke coronary collateral growth should incorporate approaches to limit or neutralize the effects of growth inhibitors.
Topics: Aged; Angiostatins; Collateral Circulation; Coronary Artery Bypass; Coronary Artery Disease; Female; Fibrinolysin; Humans; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Middle Aged; Pericardial Effusion; Plasminogen; Vascular Endothelial Growth Factor A
PubMed: 15840902
DOI: 10.1152/ajpheart.00669.2004 -
Experimental Cell Research Feb 2005Previous studies demonstrate that one of the six plasminogen type 2 glycoforms, plasminogen 2epsilon, enhances invasiveness of the 1-LN human prostate tumor cell line in...
Previous studies demonstrate that one of the six plasminogen type 2 glycoforms, plasminogen 2epsilon, enhances invasiveness of the 1-LN human prostate tumor cell line in an in vitro model. Binding of plasminogen 2epsilon to CD26 on the cell surface induces a Ca(2+) signaling cascade which stimulates the expression of matrix metalloproteinase-9, required by these cells to invade Matrigel. We now report that angiostatin, a fragment derived from plasminogen which prevents endothelial cell proliferation, is also a potent, direct inhibitor of 1-LN tumor cell invasiveness. We studied the effect of individual plasminogen 2 glycoform-derived angiostatins and found that only angiostatin 2epsilon binds to CD26 on the surface of 1-LN cells at a site also recognized by plasminogen 2epsilon. As a result, the plasminogen 2epsilon-induced Ca(2+) signaling cascade is inhibited, the expression of matrix metalloproteinase-9 is suppressed, and invasion of Matrigel by 1-LN cells is blocked. Angiostatin 2epsilon is also the only angiostatin glycoform which is able to inhibit in vitro endothelial cell proliferation and tubule formation. These studies suggest that, in addition to its ability to inhibit tumor vascularization, angiostatin 2epsilon may also directly block tumor metastasis.
Topics: Angiostatins; Cell Movement; Dipeptidyl Peptidase 4; Endothelial Cells; Humans; Male; Matrix Metalloproteinase 9; Plasminogen; Prostatic Neoplasms; Tumor Cells, Cultured
PubMed: 15572024
DOI: 10.1016/j.yexcr.2004.09.008 -
European Journal of Clinical... Jan 2003As a result of the more effective treatment of primary tumours, the incidence of leptomeningeal metastases (LM) is increasing. Current treatment modalities have little...
BACKGROUND
As a result of the more effective treatment of primary tumours, the incidence of leptomeningeal metastases (LM) is increasing. Current treatment modalities have little effect on the survival of patients with LM. We investigated whether antiangiogenic treatment inhibits the progression of leptomeningeal tumours.
MATERIALS AND METHODS
To assess the role of angiogenesis in leptomeningeal tumours, we inoculated melanoma cells in the subarachnoid space in balb/c mice. At different stages, the mice were sacrificed and the microvessel density was determined. Human specimens of LM were compared with the mouse model. For the intervention studies, the mice were treated with the angiogenesis inhibitor angiostatin. Survival was the endpoint in these studies.
RESULTS
Tumour seeding in the early disease stages was concentrated around the pre-existent arachnoid vasculature. In the more advanced stages, the tumour masses covered larger areas of the leptomeninges. Arachnoidal microvessel density in this advanced stage was increased compared with control mice. Systemic treatment of the mice with LM with angiostatin (100 mg kg-1 day-1) resulted in prolonged survival compared with mice treated with vehicle and with approximately one-fifth of the long-term survivors of the angiostatin-treated group.
CONCLUSIONS
This study shows that neovascularization is important in the growth of LM in mice. Systemic targeting of the vascular compartment may be a useful approach in novel therapeutic strategies for patients with LM.
Topics: Angiogenesis Inhibitors; Angiostatins; Animals; Antineoplastic Agents; Humans; Male; Melanoma; Meningeal Neoplasms; Mice; Mice, Inbred BALB C; Neoplasm Transplantation; Neovascularization, Pathologic; Peptide Fragments; Plasminogen; Survival Rate
PubMed: 12492456
DOI: 10.1046/j.1365-2362.2003.01056.x -
Cancer Research May 2007The antiangiogenic protein angiostatin inhibits ATP synthase on the endothelial cell surface, blocking cellular proliferation. To examine the specificity of this...
The antiangiogenic protein angiostatin inhibits ATP synthase on the endothelial cell surface, blocking cellular proliferation. To examine the specificity of this interaction, we generated monoclonal antibodies (mAb) directed against ATP synthase. mAb directed against the beta-catalytic subunit of ATP synthase (MAb3D5AB1) inhibits the activity of the F(1) domain of ATP synthase and recognizes the catalytic beta-subunit of ATP synthase. We located the antibody recognition site of MAb3D5AB1 in domains containing the active site of the beta-subunit. MAb3D5AB1 also binds to purified Escherichia coli F(1) with an affinity 25-fold higher than the affinity of angiostatin for this protein. MAb3D5AB1 inhibits the hydrolytic activity of F(1) ATP synthase at lower concentrations than angiostatin. Like angiostatin, MAb3D5AB1 inhibits ATP generation by ATP synthase on the endothelial cell surface in acidic conditions, the typical tumor microenvironment where cell surface ATP synthase exhibits greater activity. MAb3D5AB1 disrupts tube formation and decreases intracellular pH in endothelial cells exposed to low extracellular pH. Neither angiostatin nor MAb3D5AB1 showed an antiangiogenic effect in the corneal neovascularization assay; however, both were effective in the low-pH environment of the chicken chorioallantoic membrane assay. Thus, MAb3D5AB1 shows angiostatin-like properties superior to angiostatin and may be exploited in cancer chemotherapy.
Topics: Adenosine Triphosphate; Angiostatins; Animals; Antibodies, Monoclonal; Binding Sites, Antibody; Biomimetic Materials; Catalytic Domain; Cattle; Chorioallantoic Membrane; Corneal Neovascularization; Endothelial Cells; Epitope Mapping; Female; Humans; Hydrogen-Ion Concentration; Mice; Mice, Inbred BALB C; Mitochondrial Proton-Translocating ATPases; Models, Molecular; Neovascularization, Physiologic; Rats; Rats, Inbred F344
PubMed: 17510399
DOI: 10.1158/0008-5472.CAN-06-1094