Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1519670 (tumor angiogenesis)
 6,052 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antithrombotic effect of abciximab is believed to be primarily due to its blockade of platelet glycoprotein IIb/IIIa receptors, leading to the inhibition of platelet aggregation. Studies have, however, identified that antibody 7E3, the parent molecule of abciximab, and/or abciximab itself, binds to both "activated" alphaMbeta2 receptors and alphaVbeta3 receptors. Because alphaMbeta2 receptors are present on granulocytes and monocytes, cells that have been implicated in contributing to atherosclerosis, intimal hyperplasia after vascular injury, reperfusion injury, and thrombin generation, it is possible that some of abciximab's effects relate to this reactivity. Similarly, because alphaVbeta3 has been implicated in platelet adhesion to osteopontin, intimal hyperplasia after vascular injury, and platelet-mediated thrombin generation, it is possible that some of abciximab's beneficial effects relate to this reactivity. Blockade of alphaVbeta3 receptors may also be beneficial in other disease states because, in animal models, such blockade inhibits tumor angiogenesis and sickle cell adhesion to blood vessel endothelium. Despite these intriguing observations, there are no direct data to support any beneficial roles or any unwanted side effects related to the reactivities of abciximab with "activated" alphaMbeta2 or alphaVbeta3 receptors.
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PMID:Potential non-glycoprotein IIb/IIIa effects of abciximab. 1038 84

Tumor growth and metastasis are angiogenesis-dependent processes initiated and regulated by a number of cytokines. Vascular endothelial growth factor (VEGF) is a potent angiogenic protein with a selective mitogenic effect on vascular endothelial cells. Osteopontin (OPN) induces endothelial cell migration and upregulates endothelial cell migration induced by VEGF. To clarify the cooperative role of VEGF and OPN in tumor angiogenesis, we stained VEGF, OPN, and CD34 immunohistochemically in 87 cases of stage I non-small cell lung cancer (adenocarcinoma, 55, and squamous cell carcinoma, 32). Of the 87 patients studied, 27 patients had postoperative relapse and 60 patients did not. VEGF was found in 34 of 55 cases of adenocarcinomas and 14 of 32 squamous cell carcinomas, and OPN was found in 30 of 55 adenocarcinomas and 10 of 32 squamous cell carcinomas. In adenocarcinoma, microvessel counts of VEGF-positive and OPN-positive tumors were significantly higher than VEGF-negative and OPN-negative tumors, respectively, whereas in squamous cell carcinoma they were not. More importantly, patients with VEGF- and OPN-positive stage I lung adenocarcinoma had significantly worse prognosis as compared with other groups. Cooperation of OPN is important in VEGF-mediated tumor angiogenesis in stage I lung adenocarcinoma.
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PMID:Vascular endothelial growth factor and osteopontin in stage I lung adenocarcinoma. 1050 18

Tumor growth and metastasis are angiogenesis-dependent and tumor angiogenesis is a result of complex interplay of positive and negative regulators. Vascular endothelial growth factor (VEGF) occupies a particular place among the positive regulators of angiogenesis due to its potency and specificity for endothelial cells. VEGF upregulates several molecules such as growth factors, adhesion molecules, proteases, and protease receptors and it actually induces microvascular hyperpermeability, resulting in activation of thrombin from prothrombin. Osteopontin (OPN) is a secreted arginine-glycine-asparic acid (RGD)-containing phosphoprotein and it contains a predicted thrombin cleavage site. OPN binds to several integrins and CD44 variants. OPN has diverse functions such as cell adhesion, chemoattraction, and immunomodulation, and it induces endothelial cell migration and upregulates endothelial cell migration induced by VEGF. OPN expression is upregulated in human carcinomas. This review documents the functional roles of VEGF and OPN in angiogenesis and their clinical significance in tumor biology.
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PMID:Vascular endothelial growth factor and osteopontin in tumor biology. 1100 9

The scenario of multiple genetic and epigenetic alterations found in gastric carcinoma differs depending upon the two histological types, indicating that well differentiated or intestinal type and poorly differentiated or diffuse type gastric carcinomas have different genetic pathways. Cancer-stromal interaction through growth factor/cytokine receptor system which plays a central role in invasion and metastasis, is also different between the two types of stomach cancer. The majority of gastric carcinoma exhibit co-expression of IL-8 and its two receptors that evidently confer tumor angiogenesis. IL-8 increases the expression of EGF receptor, VEGF and IL-8 itself by tumor cells themselves, whereas IL-8 decreases expression of E-Cadherin, associated with increase in expression and activity of MMP-9 by tumor cells. These findings overall suggest that IL-8 produced by gastric cancer cells is used for sustained angiogenesis and tissue invasion and metastasis via autocrine/paracrine manners. On the other hand, co-expression of osteopontin (OPN) and CD44v9 in tumor cells correlates well with the degree of lyiphatic vessel invasion or long distant lymph node metastasis in diffuse type gastric carcinoma, indicating that mutual interaction between OPN and CD44v9 on the tumor cells is implicated in lymphogenous metastasis. In addition to these factors, tumor invasion and metastasis requires telomere maintenance regulated by telomerase activity. The human telomerase catalytic subunit, hTERT, is strongly expressed in almost all primary tumors and nodal metastasis.
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PMID:Molecular aspects of invasion and metastasis of stomach cancer. 1121 48

Angiogenesis is an essential process for tumor growth and is regulated by tumor-derived angiogenic cytokines. Osteopontin (OPN) is one of the cytokines produced by various tumor cells and is suggested to be involved in angiogenesis by upregulating endothelial cell migration in cooperation with vascular endothelial cell growth factor (VEGF). To provide evidence of OPN involvement in a causal role in tumor angiogenesis, we generated a stable transfectant from murine neuroblastoma C1300 cells to constitutively secrete high levels of murine OPN. The OPN mRNA expression and protein secretion were confirmed by RT-PCR and ELISA, respectively. The biological activity of secreted OPN was determined with migration assay by using human umbilical vein endothelial cells (HUVEC). Transfection with OPN gene did not increase VEGF production and did not affect gene expression of other angiogenic factors confirmed by complementary DNA macroarray system. To demonstrate the effect of OPN on tumor-induced angiogenesis in vivo, millipore chambers containing OPN-transfected or control cells were implanted to the dorsal air sac of mice. The OPN-transfected cells significantly induced neovascularization in comparison to the control cells in mice. Conclusively, these results provide direct evidence of OPN involvement in the role of tumor angiogenesis.
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PMID:Osteopontin induces angiogenesis of murine neuroblastoma cells in mice. 1192 Jun 39

Lung cancer is one of the commonest causes of cancer death in developed countries. Recent evidence suggests that angoigenesis is related to poor prognosis in many solid tumors including non-small cell lung cancer (NSCLC). Angiogenesis is regulated by a complex interaction among growth factors and cytokines and influenced by proteolytic enzymes such as plasminogen activators and matrix metalloproteases, expression of adhesion molecules, and distribution of extracellular matrices. Fibroblasts, macrophages, mast cells, and endothelial cells themselves also affect angiogenesis. This review concentrates on angiogenic growth factors including vascular endothelial growth factor, angiopoietins, platelet derived endothelial growth factor, and basic fibroblast growth factor, proteases, adhesion molecules including vascular endothelial cadherin and integrins, osteopontin, and mast cell products in tumor angiogenesis of NSCLC.
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PMID:Tumor angiogenesis of non-small cell lung cancer. 1253 73

Osteopontin (OPN) plays an important role in tumorigenesis, tumor invasion, and metastasis in many types of cancers, including gastric cancer. Recently, much interest has been focused on the role of OPN in tumor angiogenesis. Our previous studies have shown that OPN is overexpressed, and associated with mean microvessel density in, the tissue samples of patients with gastric cancer. In the present study, we aimed to further determine and provide evidence for the role of OPN in gastric-cancer-associated angiogenesis by diminishing OPN expression in gastric cancer cells using the small interference RNA method, and then evaluate the effects of OPN on gastric cancer-associated angiogenesis by in vivo and in vitro assays. Our results revealed that reduced OPN production by gastric cancer cells would reduce the proliferation, migration, and tube formation of human umbilical vein endothelial cells, and lead to a lower microvessel density, i.e., angiogenesis, in transplanted tumors of mice. These data confirm the positive role of OPN in gastric-cancer-associated angiogenesis.
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PMID:Inhibition of osteopontin would suppress angiogenesis in gastric cancer. 1746 50

Osteopontin (OPN) is a secreted protein that is overexpressed in a number of human cancers, and has been associated with increased metastatic burden and poor prognosis in breast cancer patients. The OPN protein contains several conserved structural elements including heparin- and calcium-binding domains, a thrombin-cleavage site, a CD44 binding site, and two integrin-binding sites. Experimental studies have shown that the ability of OPN to interact with a diverse range of factors, including cell surface receptors (integrins, CD44), secreted proteases (matrix metalloproteinases, urokinase plasminogen activator), and growth factor/receptor pathways (TGFalpha/EGFR, HGF/Met) is central to its role in malignancy. These complex signaling interactions can result in changes in gene expression, which ultimately lead to alterations in cell properties involved in malignancy such as adhesion, migration, invasion, enhanced tumor cell survival, tumor angiogenesis, and metastasis. Therefore, OPN is not merely associated with cancer, but rather it plays a multi-faceted functional role via complex molecular cross-talk with other factors. This review will focus on the role of OPN in breast cancer, in particular on the malignancy-promoting aspects of OPN that may reveal opportunities for new approaches to the clinical management of breast cancer.
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PMID:Osteopontin overexpression in breast cancer: knowledge gained and possible implications for clinical management. 1772 86

Angiogenesis is the hallmark of cancer, and development of aggressiveness of primary tumor depends on de novo angiogenesis. Here, using multiple in vitro and in vivo models, we report that osteopontin (OPN) triggers vascular endothelial growth factor (VEGF)-dependent tumor progression and angiogenesis by activating breast tumor kinase (Brk)/nuclear factor-inducing kinase/nuclear factor-kappaB (NF-kappaB)/activating transcription factor-4 (ATF-4) signaling cascades through autocrine and paracrine mechanisms in breast cancer system. Our results revealed that both exogenous and tumor-derived OPN play significant roles in VEGF-dependent tumor angiogenesis. Clinical specimen analysis showed that OPN and VEGF expressions correlate with levels of neuropilin-1, Brk, NF-kappaB, and ATF-4 in different grades of breast cancer. Consequently, OPN plays essential role in two key aspects of tumor progression: VEGF expression by tumor cells and VEGF-stimulated neovascularization. Thus, targeting OPN and its regulated signaling network could be a novel strategy to block tumor angiogenesis and may develop an effective therapeutic approach for the management of breast cancer.
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PMID:Osteopontin promotes vascular endothelial growth factor-dependent breast tumor growth and angiogenesis via autocrine and paracrine mechanisms. 2716 Mar 11

Both vascular endothelial growth factor A (VEGF) and osteopontin (OPN) can directly induce tumor angiogenesis, which is essential for the growth and metastasis of solid tumors. Here we engineered a bispecific antibody (VEGF/OPN-BsAb) using the anti-VEGF-A antibody bevacizumab and the anti-OPN antibody hu1A12. Compared with hu1A12 alone and bevacizumab alone, VEGF/OPN-BsAb was significantly more effective in inhibiting tumor angiogenesis in a highly metastatic human hepatocellular carcinoma nude mouse model. Further study demonstrated that VEGF/OPN-BsAb could effectively suppress primary tumor growth and metastasis to lungs, suggesting that it might be a promising therapeutic agent for treatment of metastatic cancer.
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PMID:A bispecific antibody effectively inhibits tumor growth and metastasis by simultaneous blocking vascular endothelial growth factor A and osteopontin. 2082 49


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