Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P39060 (endostatin)
 2,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previously, we described FGF-1- or FGF-4-transfected MCF-7 breast carcinoma cells which are tumorigenic and metastatic in untreated or tamoxifen-treated ovariectomised nude mice. In this study, we have assessed the effects of AGM-1470, an antiangiogenic agent, and pentosan polysulphate (PPS), an agent that abrogates the effects of FGFs, on tumour growth and metastasis produced by these FGF-transfected MCF-7 cells. Untreated or tamoxifen-treated ovariectomised mice were injected with FGF-transfected cells, treated with AGM-1470 or PPS, and tumour growth and metastasis analysed. The sensitivity of FGF-transfected and parental MCF-7 cells to AGM-1470 or PPS was also determined in vitro. Both AGM-1470 and PPS inhibited tumour growth in otherwise untreated or tamoxifen-treated mice injected with either FGF- or FGF-4-transfected MCF-7 cells. This effect was more reliably seen in tamoxifen-treated animals. AGM-1470 was about 10(5) times less potent in inhibiting the anchorage-dependent growth of parental MCF-7 or FGF-transfected MCF-7 cells than in inhibiting the growth of human umbilical vein endothelial cells. PPS did not affect the in vitro growth of the transfectants or parental cells. Thus, the growth-inhibitory effect on tumours was in excess of the effect of either drug on the same cells in tissue culture, implying that stromal elements are important determinants of the effects of these drugs. There was a positive correlation between tumour size and the extent of proximal lymph node metastasis. However, neither drug had a significant effect on the extent of metastasis to proximal or distal lymph nodes or lungs. AGM-1470 or PPS may be helpful in cases of breast carcinoma in which angiogenesis is due to expression of FGFs by the tumour cells and may be more effective when combined with tamoxifen.
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PMID:Effects of AGM-1470 and pentosan polysulphate on tumorigenicity and metastasis of FGF-transfected MCF-7 cells. 862 63

Endostatin is a carboxyl-terminal proteolytic fragment of collagen XVIII and a potent inhibitor of angiogenesis. The mechanism of action is unknown, but the crystal structure of endostatin predicts a prominent heparan sulfate binding site, suggesting that endostatin competitively inhibits heparin-binding angiogenic factors, such as basic fibroblast growth factor (FGF-2). The goal of the study was to map endostatin binding sites in intact human tissues and to determine whether this binding is heparan sulfate dependent. In situ binding was performed with recombinant epitope-tagged murine endostatin. Endostatin predominantly binds to blood vessels of different calibers in a saturable fashion. In addition, binding to some epithelial basement membranes is seen. The localization pattern is similar to that reported for collagen XVIII, endostatin's parent molecule. In breast carcinomas, endostatin co-localizes largely with FGF-2. In a surprising contrast to FGF-2, endostatin binding is resistant to treatment with heparitinase, demonstrating that binding is not mediated by heparan sulfate proteoglycans. Furthermore, FGF-2 and heparin do not compete for endostatin binding, providing additional evidence for the discreteness of endostatin and FGF-binding sites.
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PMID:Endostatin binds to blood vessels in situ independent of heparan sulfate and does not compete for fibroblast growth factor-2 binding. 1039 39

A number of clinical studies have demonstrated the prognostic significance of angiogenesis and angiogenic growth factors in solid tumours; however, very little is known about the relevance of these parameters in haematological malignancies. We evaluated circulating levels of angiogenic growth factors and endostatin in 36 non-Hodgkin's lymphoma (NHL) patients. Baseline vascular endothelial growth factor (VEGF) levels of patients in complete remission (CR) after a median follow-up of 21 months were significantly lower than those of patients with progressive disease (P = 0.016). Event-free survival (EFS) rate was significantly higher in patients who had baseline VEGF and basic-fibroblast growth factor (b.FGF) levels below the median values of 147 and 19.5 pg/ml (P = 0.018 and 0.039 by log-rank test, respectively). Conversely, the levels of endostatin, angiogenin and leptin were not different in CR patients compared to relapsed patients and did not correlate with EFS. Our data suggest that b-FGF and, particularly, VEGF might be considered prognostic factors in NHL staging and management.
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PMID:Angiogenic growth factors and endostatin in non-Hodgkin's lymphoma. 1084 4

Endostatin, which corresponds to the C-terminal fragment of collagen XVIII, is a potent inhibitor of angiogenesis. Fibroblast growth factor-2 (FGF-2)-induced angiogenesis in the chicken chorioallantoic membrane was inhibited by endostatin, but not by an endostatin mutant R158/270A, lacking heparin-binding ability. Endostatin was internalized by endothelial cells, but not by mouse fibroblasts. Treatment of murine brain endothelial (IBE) cells with endostatin reduced the proportion of cells in S phase, whereas growth-arrested IBE cells in collagen gels treated with endostatin displayed enhanced tubular morphogenesis. IBE cells overexpressing Shb, an adaptor protein implicated in angiostatin-induced apoptosis, displayed elevated apoptosis and decreased tubular morphogenesis in collagen gels in response to endostatin when added together with FGF-2. Induction of apoptosis was dependent on the heparin-binding ability of endostatin and the expression of Shb with a functional Src homology 2 (SH2)-domain. Endostatin treatment for 10 minutes or 24 hours induced tyrosine phosphorylation of Shb and formation of multiprotein complexes. An Shb SH2 domain fusion protein precipitated a 125-kd phosphotyrosyl protein in endostatin-treated cells. The 125-kd component either contained intrinsic tyrosine kinase activity or occurred in complex with a tyrosine kinase. In conclusion, our data show that endostatin induces tyrosine kinase activity and enhanced apoptosis in FGF-treated endothelial cells.
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PMID:Endostatin-induced tyrosine kinase signaling through the Shb adaptor protein regulates endothelial cell apoptosis. 1082 22

Progressive growth and metastasis of solid tumors require angiogenesis, or the formation of new blood vessels. Endostatin is a 20-kDa carboxy-terminal fragment of collagen XVIII that has been shown to inhibit endothelial cell proliferation and tumor angiogenesis. Replication-deficient recombinant adenovirus (rAd) vectors were constructed, which encoded secreted forms of human and mouse endostatin (HECB and MECB, respectively), and, as a control, human alkaline phosphatase (APCB). Accumulation of endostatin was demonstrated in supernatants of cultured cells infected with the endostatin rAds. These supernatants disrupted tubule formation, inhibited migration and proliferation, and induced apoptosis in human dermal vascular endothelial cells or human vascular endothelial cells. Endostatin-containing supernatants had no effect on the proliferation of MidT2-1 mouse mammary tumor cells in vitro. A pharmacokinetic study of MECB in immunocompetent FVB mice demonstrated a 10-fold increase of serum endostatin concentrations 3 days after intravenous administration of 1x10(10) particles of this rAd (215-257 ng/mL compared to 12-38 ng/mL in control rAd-treated mice). Intravenous administration of MECB reduced b-FGF stimulated angiogenesis into Matrigel plugs by 38%. Intratumoral MECB inhibited growth of MidT2-1 syngeneic mammary tumors in FVB mice, but had minimal impact on the growth of MDA-MB-231 human breast tumors in SCID mice. Intravenous therapy with MECB also initially inhibited growth of MidT2-1 tumors, but this activity was subsequently blocked by induced anti-rAd antibodies. In summary, endostatin gene therapy effectively suppressed angiogenic processes in vitro and in vivo in several model systems.
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PMID:Evaluation of endostatin antiangiogenesis gene therapy in vitro and in vivo. 1178 61

Fibrinolysis is a precisely orchestrated process in which fibrin-containing thrombi are solubilized. Several receptors regulate this process by localizing proteolytic activity to the cell surface. One such receptor is annexin II, a calcium and phospholipid-binding protein. Annexin II serves as a profibrinolytic coreceptor for both plasminogen and tissue plasminogen activator on the surface of endothelial cells and facilitates the generation of plasmin. The dysregulation of fibrinolytic assembly on endothelial cells may lead to atherothrombotic disease. In addition to its role in fibrinolysis at the surface of endothelial cells, annexin II may play other potential cellular roles. For example, the overexpression of annexin II on the surface of leukemic cells and cell lines derived from acute promyelocytic leukemia correlates with both the clinical manifestation of bleeding and the in vitro ability of the leukemic cells to generate plasmin. The abundant presence of annexin II on the surface of other cell types including monocytic cell lines and different cancer cells may contribute to their invasive potential through extracellular matrix either by generation of plasmin or, by plasmin-mediated proteolytic activation of other metalloproteinases. This dissolution of extracellular matrix may also cause the release of potent matrix-bound angiogenic factors such as VEGF and FGF. On the other hand, by increasing the pool of plasmin, a precursor to an important anti-angiogenic factor, angiostatin, and by fragmentation of collagen XVIII (a precursor to the anti-angigenic factor, endostatin) by plasmin-activated metalloproteases, annexin II could play a pivotal physiological role in the pro- and anti-angiogenic switch mechanism.
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PMID:Annexin II: a plasminogen-plasminogen activator co-receptor. 1181 88

To isolate matrix molecules with angiogenic activity, tumor extracellular matrix (ECM) fractions from the basement membrane preparation Matrigel were analyzed for effects on endothelial cell (EC) proliferation, differentiation, and vessel formation in vivo. Inhibition of human and bovine EC DNA synthesis was evident upon treatment with several soluble Matrigel fractions including conditioned media (MGCM). After size fractionation of MGCM, EC growth arrest was activated by factor(s) smaller than 3,000 daltons (3KF). Bovine EC differentiation (tube formation) was promoted by both MGCM and 3KF fractions in two different models using matrigel or collagen gels to stimulate tube formation. The 3KF factor(s) stimulated angiogenesis when implanted in the cornea or subcutaneously in mice. FGF-induced angiogenesis and blood flow were increased in the presence of 3KF factor(s), an effect that was inhibited by the anti-angiogenic molecule endostatin. Further characterization of the low molecular weight 3KF samples by RP-HPLC revealed several fractions exhibiting EC growth arrest activity. These results suggest that the ability of ECM preparations to induce EC growth arrest and tube formation may reside, at least partially, in previously undetected low molecular weight molecules. Characterization of these ECM-associated inhibitors may lead to the development of novel anti-angiogenic and anti-tumor compounds.
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PMID:Extracellular matrix-derived angiogenic factor(s) inhibit endothelial cell proliferation, enhance differentiation, and stimulate angiogenesis in vivo. 1182 74

The process of new capillary formations from previously existing mature vessels in healthy individuals has been mainly studied during cycles of the female reproductive tract. This new capillary formation, known as angiogenesis is related to endogenous regulators that both stimulates or inhibits it. Knowledge on the role of both stimulators and inhibitors under physiological and pathological conditions accentuates a main role of VEGF, FGF, angiogenin and angiopoietics among the formers; and main role of angiostatin and endostatin among the latters. In recent years, angiogenesis in the ovaries that leads to follicular and luteal growth and development has been extensively studied. Whether a number of endogenous stimulators and inhibitors have been identified, the molecular link between the endocrine and vascular system is not fully understood. Therefore, efforts to formulate questions that need answers must be made.
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PMID:[Angiogenesis in reproductive physiology. Follicular development, formation and maintenance of the corpus luteum]. 1191 46

Human pancreatic ribonuclease-1 (RNase1) does not exhibit its cytotoxicity unless it is artificially internalized into the cytosol. Furthermore, once it encounters the cytosolic RNase inhibitor (RI), the activity of RNase1 is seriously reduced. To achieve the cellular targeting of RNase1 and the blocking of RI binding simultaneously, the basic fibroblast growth factor (bFGF) sequence was inserted into RNase1 at the RI binding site using a gene fusion technique. The effect of this fusion protein, CL-RFN89, on the angiogenesis, which was accelerated by FGF-FGF receptor interaction, was investigated. It was shown by using fluorescein-labeled CL-RFN89, that the binding to human umbilical vein endothelial cells (HUVECs) was dependent on the existence of the FGF receptors. In addition, CL-RFN89 inhibited the cellular growth of HUVECs in vitro and also inhibited the tube formation, using a three-dimensional tube formation assay. Furthermore, this fusion protein was shown to prevent in vivo tumor cell-induced angiogenesis, using the mouse dorsal air sac assay. These results demonstrated that CL-RFN89 inhibits angiogenesis in vitro and in vivo and that it can be expected to be a potent antiangiogenic agent.
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PMID:Anti-angiogenic effect of an insertional fusion protein of human basic fibroblast growth factor and ribonuclease-1. 1598 15

In patients with stage IIB-III disease, adjuvant high-dose interferon-alpha2b has shown clinical benefit, although metastatic melanoma is currently without any known survival-prolonging therapy. Angiogenesis has been considered important in melanoma progression, and endostatin is an angiogenesis inhibitor with antitumor activity that has shown promising results in murine model systems, prompting investigation of a formulation of rh-Endostatin (EntreMed, Rockville, Maryland, USA) alone and with interferon in metastatic melanoma. Patients were randomly assigned to receive interferon alpha2b (Schering-Plough) 10 million units/m(2) subcutaneously three times a week plus rh-Endostatin 45 mg/m(2) subcutaneously every 12 h (arm A) vs. rh-Endostatin alone (arm B). Twenty-one patients (age range 31-77 years, median age 54, 12 men and nine women, 17 cutaneous, and four ocular melanomas) were enrolled. No antitumor responses were observed, and no significant differences were noted in time to progression or overall survival. Two patients had stable disease enduring more than 30 weeks on treatment. Serum endostatin levels increased significantly 4 weeks after treatment in both groups. Basic fibroblast growth factor levels in urine were significantly lower following treatment in patients on arm B (P=0.043). The percentage of circulating endothelial cells was increased in five evaluable patients 4 weeks after treatment. Low titer (<or=1:25) IgG antibodies against the rh-Endo formulation were detected in two patients (one per arm) in cycle 4. In conclusion, interferon did not improve response rate of rh-Endo although prolonged disease stability was observed in two patients. Better laboratory correlates of antiangiogenic response are needed, and the predictive value of circulating endothelial cells warrants further evaluation.
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PMID:Endostatin plus interferon-alpha2b therapy for metastatic melanoma: a novel combination of antiangiogenic and immunomodulatory agents. 1750 65


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