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Query: UNIPROT:P39060 (
endostatin
)
2,284
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Wound healing is a process with immunological and angiogenic aspects. rhGM-CSF is known to stimulate the immune system and angiogenesis via multiple pathways. In this study we investigated the combined effects of surgery, with or without rhGM-CSF, on angiogenic parameters in patients with a colorectal carcinoma. In this phase II randomized, placebo-controlled trial, 16 patients were assigned to perioperative rhGM-CSF (2.8 microg/kg body weight) treatment or saline. Patients received subcutaneous injections from three days before surgery until four days after. IL-6,
VEGF
,
endostatin
and angiostatin levels were measured perioperatively. rhGM-CSF enhanced the production of IL-6 and
VEGF
, but had no effect on the antiangiogenic agents
endostatin
and angiostatin. Surgery induced a transient decrease of
endostatin
. Two types of angiostatin (kringle 1-3 and kringle 1-4) became visible postoperatively. We conclude that this study demonstrated the immediate initiation of angiogenesis postoperatively, reflected by the increase of
VEGF
and a transient decrease of
endostatin
, followed by the appearance of two angiostatin bands, which confirms physiological wound healing in these cancer patients.
...
PMID:The effects of surgery, with or without rhGM-CSF, on the angiogenic profile of patients treated for colorectal carcinoma. 1469 62
Angiogenesis is controlled by anti-angiogenic factors as well as by angiogenic factors, such as
VEGF
(vascular endothelial growth factor) and HGF (hepatocyte growth factor). Endostatin, a potent endogenous angiogenesis inhibitor, is known to inhibit endothelial proliferation and suppress tumour growth. However, to date, little is known about the pathophysiology of
endostatin
in ischaemia/reperfusion. To investigate the mechanisms of angiogenesis induced by myocardial ischaemia/reperfusion in more detail, we studied the circulating levels of
endostatin
,
VEGF
and HGF in 17 patients with acute myocardial infarction, who underwent early reperfusion therapy. In all patients, serum
endostatin
,
VEGF
and HGF levels before reperfusion were increased significantly compared with those in 17 control subjects (
endostatin
, 49.2+/-11.7 ng/ml, but not detectable in controls;
VEGF
, 685.6+/-150.3 pg/ml compared with 173.7+/-33.6 pg/ml; HGF, 3638+/-1285 pg/ml compared with 59+/-13 pg/ml; values are means+/-S.E.M.). After reperfusion, the serum
endostatin
and
VEGF
levels decreased significantly, but still remained higher than those in control subjects (
endostatin
, 19.6+/-7.0 ng/ml;
VEGF
, 284.2+/-90.2 pg/ml). In contrast, serum HGF levels increased significantly (15 146+/-2230 pg/ml) after reperfusion. These data indicated that serum levels of
endostatin
changed in parallel with those of
VEGF
in response to myocardial ischaemia/reperfusion, and the marked increase in serum HGF levels after reperfusion seemed to be, at least in part, due to heparin administration. Our data offer a possible anti-
endostatin
therapy in patients with acute myocardial infarction to facilitate collateral vessel formation.
...
PMID:Serum levels of endostatin, vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) in patients with acute myocardial infarction undergoing early reperfusion therapy. 1523 Jun 92
TNP-470 (AGM-1470), an analogue of fumagillin, was one of the first molecules proposed to have antiangiogenic properties. This concept was based on its ability to inhibit both endothelial proliferation in vitro and tumor growth in vivo in a number of xenograft models. Yet, subsequent investigations indicated that the biochemical activities associated with TNP-470 are not selective for endothelial cells. Moreover, recent evidence suggests that this agent inhibits tumor growth in vivo, but without a corresponding decrease in angiogenesis. Therefore, we performed a detailed comparison of TNP-470 to a validated
antiangiogenic agent
, a
VEGF
inhibitor termed
VEGF
-Trap, using a xenograft model of Wilms tumor. Treatment with TNP-470 for 5 weeks significantly suppressed xenograft growth (83%). Surprisingly, this inhibition was not associated with a decrease in angiogenesis, but instead with an increase in tiny neovessels. To determine whether this was a direct effect of TNP-470 on tumor vessels, we examined its effect in a short-term assay using large tumors with established vasculature. In contrast to treatment with
VEGF
-Trap, which led to rapid vessel regression and tumor hypoxia, tumors exposed to TNP-470 for 1 day displayed increased capillary sprouting, with significantly increased microvessel density, vessel length, and branch points. TNP-470 did not induce tumor hypoxia as demonstrated by minimal pimonidazole staining and
VEGF
expression. TNP-470 did, however, cause a marked increase in apoptosis of tumor cells. Our results indicate that the antitumor effects of TNP-470 cannot be attributed to prevention of neoangiogenesis, but instead to its direct action on tumor cells.
...
PMID:TNP-470 promotes initial vascular sprouting in xenograft tumors. 1502 54
Angiogenesis, the growth of new capillaries from pre-existing vessels, contributes to the development and progression of a variety of physio-pathological conditions. There is growing evidence that anti-angiogenic drugs will improve future therapies of diseases like cancer, rheumatoid arthritis and ocular neovascularisation. Conversely, therapeutic angiogenesis is an important homeostatic response contributing to limit the damage to ischemic tissues. Molecular processes involved in angiogenesis include stimulation of endothelial growth by cytokine production (i.e. vascular endothelial growth factor,
VEGF
; fibroblast growth factor-2, FGF-2), degradation of extracellular matrix proteins by matrix metalloproteinases (MMPs), and migration of endothelial cells mediated by integrins (cell membrane adhesion molecules). Drugs targeting pathologic angiogenesis have been designed to interfere with any of these steps and are currently undergoing evaluation in early clinical studies. Important therapeutic strategies are: suppression of activity and signaling pathways activated by the major angiogenic regulators like
VEGF
and FGF-2; inhibition of function of alphav-integrins and MMPs; exploitation of endogenous anti-angiogenic molecules like angiostatin and
endostatin
. The strategy to "silence" endothelium with antiangiogenic drugs to starve tumors, provides a novel approach for cancer treatment. The unique targets of these drugs (endothelium) make them distinct from traditional cytotoxic chemotherapeutic agents. Conversely, gene transfer of angiogenesis inducers is the new approach for therapeutic neovascularization, which is under investigation using a variety of growth factors and a wide array of potential delivery systems, including the application of the gene as naked DNA or by viral vector. The status of pro- and anti-angiogenic therapies is here presented and discussed.
...
PMID:Development of new drugs in angiogenesis. 1521 14
Angiogenesis is characterized by the development of new vasculature from pre-existing vessels and plays a central role in physiological processes such as embryogenesis, wound healing and female reproductive function, as well as pathophysiologic events including cancer, rheumatoid arthritis and diabetic retinopathy. The growth and metastasis of tumors is critically dependent upon angiogenesis. Although targeting angiogenesis as a therapeutic strategy has to date met with limited success in the clinic, the recent FDA approval of the anti-
VEGF
antibody Avastin has validated the use of anti-angiogenic therapeutic strategies for cancer treatment. We have recently identified several plasma proteins having anti-angiogenic properties, including Histidine-Proline-Rich Glycoprotein (HPRG) and activated high-molecular-weight kininogen (HKa). Both of these proteins are able to induce apoptosis in endothelial cells in vitro and can inhibit angiogenesis in vivo. Recent studies from our laboratories have also identified a novel cell-surface binding protein for HKa that mediates its anti-angiogenic activity. This protein, tropomyosin, is normally found inside the cell and is associated with the actin cytoskeleton, where it plays a critical role in stabilizing actin filaments in a variety of cell types. However, in angiogenic endothelial cells, tropomyosin appears to have extracellular localization. Previous studies have also suggested the involvement of tropomyosin in the anti-angiogenic activity of
endostatin
, and our recent work indicates that tropomyosin may mediate the antiangiogenic activity of HPRG as well. In this review, we summarize data describing extracellular tropomyosin as a novel receptor for multiple anti-angiogenic proteins. Extracellular tropomyosin may therefore represent a previously undescribed central target for the development of anti-angiogenic therapy.
...
PMID:Extracellular tropomyosin: a novel common pathway target for anti-angiogenic therapy. 1557 12
The roles of proteinase-activated receptors (PARs) in platelet functions other than aggregation are not well understood. Among these is the release of factors that regulate the process of angiogenesis, such as
endostatin
and
VEGF
, which, respectively, inhibit and promote angiogenesis. PAR1 and PAR4 are expressed on the surface of human platelets and can be activated by thrombin. In the present study, we have attempted to determine the roles of PAR1 and PAR4 in regulating release of
endostatin
and
VEGF
from human platelets. Aggregation and
endostatin
release could be elicited by a specific PAR4 agonist (AYPGKF-NH(2)). The PAR4 agonist concentration dependently suppressed
VEGF
release. A selective PAR1 agonist (TFLLR-NH(2)) induced platelet aggregation and
VEGF
release but suppressed
endostatin
release. Thrombin did not affect
endostatin
or
VEGF
release. However, in the presence of a selective PAR1 antagonist (SCH79797), thrombin stimulated
endostatin
release and suppressed
VEGF
release. Conversely, in the presence of a selective PAR4 antagonist (transcinnamoyl-YPGKF-NH(2)), thrombin stimulated
VEGF
release. In vivo, treatment of rats with established gastric ulcers with a PAR1 antagonist each day for 1 wk resulted in a significant retardation of healing. We conclude that PAR1 and PAR4 counter-regulate the release of
endostatin
and
VEGF
from platelets. These protease-activated receptors could therefore play a crucial role in regulating angiogenesis and in turn could regulate the processes of wound healing and tumor growth.
...
PMID:Proteinase-activated receptors 1 and 4 counter-regulate endostatin and VEGF release from human platelets. 1561 51
Disruption of the systemic angiogenesis balance to favor enhanced angiogenesis is speculated to represent a key step in the growth of tumors. Although a major emphasis has been placed on the increase of angiogenesis stimulators, such as
VEGF
, on the disruption of the angiogenic balance, the potential role of the physiological levels of endogenous inhibitors of angiogenesis on tumor growth is poorly understood. Here, we use three independent lines of mice deficient in tumstatin,
endostatin
, or thrombospondin-1 (TSP-1), to address the role that these endogenous angiogenesis inhibitors play in tumor growth. Our experiments demonstrate that normal physiological levels of these inhibitors serve to retard the growth of tumors, and that their absence leads to enhanced angiogenesis and a 2- to 3-fold increase in tumor growth. The tumor-suppressive action of TSP-1,
endostatin
, and tumstatin correlates with expression of CD36 receptor, alpha5beta1 integrin, and alphavbeta3 integrin on proliferating endothelial cells, respectively. Moreover, tumors grow 2-fold faster in the tumstatin/TSP-1 double-knockout mice, compared with either the tumstatin- or the TSP-1-deficient mice, strongly suggesting that ceiling rate of cancer growth is not completely dependent on the genetic defects of cancer cells but also depends on the host-derived tumor microenvironment. Additionally, tumor growth in transgenic mice overproducing
endostatin
specifically in the endothelial cells (a 1.6-fold increase in the circulating levels; mimicking Down's syndrome condition) is 3-fold slower than the tumor growth in wild-type mice. Collectively, our data suggest that physiological levels of endogenous inhibitors of angiogenesis can serve as endothelium-specific tumor suppressors.
...
PMID:Function of endogenous inhibitors of angiogenesis as endothelium-specific tumor suppressors. 1571 Aug 85
Hepatocellular carcinoma (HCC) is regarded as a suitable target for antiangiogenic strategies. However, antiangiogenic agents aimed at single targets can be neutralized by upregulation of other proangiogenic factors. Therefore, combined approaches addressing at least two angiogenic targets should be more effective. Employing an appropriate rat hepatoma model, we examined the effects of sFlt-1 (soluble vascular endothelial growth factor [
VEGF
] receptor 1 as an indirect inhibitor of angiogenesis) and
endostatin
(a direct inhibitor of angiogenesis) in both single-agent as well as combined approaches under in vitro and in vivo conditions. Similar to human HCC, rat Morris hepatoma (MH) cells secreted high levels of
VEGF
, but no endogenous sFlt-1. Parental MH or MHES(r) cells, stably expressing rat
endostatin
, were adenovirally transduced either with AdsFlt-1 (encoding sFlt-1) or control vector Adnull (containing no transgene), followed by subcutaneous inoculation into syngeneic ACI rats. Compared with MH/Adnull cells, expressing no antiangiogenic factors at all, tumor weights were reduced fourfold in the MHES(r)/Adnull group, 19-fold in the MH/AdsFlt-1-group, and 77-fold in the MHES(r)/AdsFlt-1 combination therapy group. Analysis of variance did not show a significant interaction between the effects of the two factors ES(r) and sFlt-1; their effects multiplied. In conclusion, combined expression of sFlt-1 and
endostatin
effectively suppresses HCC growth under in vivo conditions. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).
...
PMID:Combined endostatin/sFlt-1 antiangiogenic gene therapy is highly effective in a rat model of HCC. 1573 85
The lysosomal protease cathepsin B has been implicated in a variety of pathologies including pancreatitis, tumor angiogenesis, and neuronal diseases. We used a tube formation assay to investigate the role of cathepsin B in angiogenesis. When cultured between two layers of collagen I, primary endothelial cells formed tubes in response to exogenously added
VEGF
. Overexpressing cathepsin B reduced the
VEGF
-dependent tube response, whereas pharmacologically or molecularly suppressing cathepsin B eliminated the dependence on exogenous
VEGF
. However, tube formation still required
VEGF
receptor activity, which suggested that endothelial cells generated
VEGF
. Indeed, VEGF mRNA and protein was detectable in cells treated with cathepsin B inhibitor, which correlated with a rise in the level of HIF-1alpha. In addition to boosting the level of proangiogenic factors, blocking cathepsin B activity reduced the amount of the antiangiogenic protein
endostatin
. Thus endothelial cells have the intrinsic capacity to generate pro- and antiangiogenic agents. These observations complement and expand our appreciation of how endothelial cell-derived proteases regulate angiogenesis.
...
PMID:Cathepsin B regulates the intrinsic angiogenic threshold of endothelial cells. 1590 32
The hypothesis that tumor growth and metastasis is angiogenesis-dependent was proposed by Judah Folkman in 1971. Its major implication is that blocking angiogenesis could be a strategy for arresting tumor growth. This hypothesis is now supported by extensive experimental evidence, and hence the angiogenic switch and microvascular endothelial cells recruited by the tumor have emerged as important targets in cancer therapy. A large number of proangiogenic and antiangiogenic factors have been discovered. At least three angiogenesis inhibitors have received FDA approval in the US, with Avastin (anti-
VEGF
-antibody) also approved in 26 other countries. The recognition that antiangiogenic therapy is becoming the fourth therapeutic modality in addition to surgery, chemotherapy and radiotherapy underlines the urgent need to understand the systems biology of the antiangiogenic response. A particularly important question for cancer therapy is whether antiangiogenic therapy will also face the same drug resistance as one sees with other treatment modalities. Recently, the cellular signaling induced by the endogenous angiogenesis inhibitor -
endostatin
- was dissected revealing that the antiangiogenic response is characterized by a large number of individual genetic signals, which are highly coordinated and interdependent. The objective of this review is to elucidate the multifaceted nature of tumor angiogenesis, and to discuss the subtle but important distinctions that exist between variations in tumor responsiveness that evolve with antiangiogenic therapy and the classic resistance that frequently develops with conventional therapy. Furthermore, this review discusses the implications of current findings for cancer treatment and potential ways of overcoming or predicting tumor resistance to these agents.
...
PMID:Endostatin: the logic of antiangiogenic therapy. 1593 43
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