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)

Angiogenesis, the formation of new blood vessels from an existing vasculature, is requisite for tumor growth. It entails intercellular coordination of endothelial and tumor cells through angiogenic growth factor signaling. Interruption of these events has implications in the suppression of tumor growth. PD166285, a broad-spectrum receptor tyrosine kinase (RTK) inhibitor, and PD173074, a selective FGFR1TK inhibitor, were evaluated for their anti-angiogenic activity and anti-tumor efficacy in combination with photodynamic therapy (PDT). To evaluate the anti-angiogenic and anti-tumor activities of these compounds, RTK assays, in vitro tumor cell growth and microcapillary formation assays, in vivo murine angiogenesis and anti-tumor efficacy studies utilizing RTK inhibitors in combination with photodynamic therapy were performed. PD166285 inhibited PDGFR-beta-, EGFR-, and FGFR1TKs and c-src TK by 50% (IC50) at concentrations between 7-85 nM. PD173074 displayed selective inhibitory activity towards FGFR1TK at 26 nM. PD173074 demonstrated (>100 fold) selective growth inhibitory action towards human umbilical vein endothelial cells compared with a panel of tumor cell lines. Both PD166285 and PD173074 (at 10 nM) inhibited the formation of microcapillaries on Matrigel-coated plastic. In vivo anti-angiogenesis studies in mice revealed that oral administration (p.o.) of either PD166285 (1-25 mg/kg) or PD173074 (25-100 mg/kg) generated dose dependent inhibition of angiogenesis. Against a murine mammary 16c tumor, significantly prolonged tumor regressions were achieved with daily p.o. doses of PD166285 (5-10 mg/kg) or PD173074 (30-60 mg/kg) following PDT compared with PDT alone (p<0.001). Many long-term survivors were also noted in combination treatment groups. PD166285 and PD173074 displayed potent anti-angiogenic and anti-tumor activity and prolonged the duration of anti-tumor response to PDT. Interference in membrane signal transduction by inhibitors of specific RTKs (e.g. FGFR1TK) should result in new chemotherapeutic agents having the ability to limit tumor angiogenesis and regrowth following cytoreductive treatments such as PDT.
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PMID:Anti-angiogenic activity of selected receptor tyrosine kinase inhibitors, PD166285 and PD173074: implications for combination treatment with photodynamic therapy. 1063 83

We generated VEGF-null fibrosarcomas from VEGF-loxP mouse embryonic fibroblasts to investigate the mechanisms of tumor escape after VEGF inactivation. These cells were found to be tumorigenic and angiogenic in vivo in spite of the absence of tumor-derived VEGF. However, VEGF derived from host stroma was readily detected in the tumor mass and treatment with a newly developed anti-VEGF monoclonal antibody substantially inhibited tumor growth. The functional significance of stroma-derived VEGF indicates that the recruitment of stromal cells is critical for the angiogenic and tumorigenic properties of these cells. Here we identified PDGF AA as the major stromal fibroblast chemotactic factor produced by tumor cells, and demonstrated that disrupting the paracrine PDGFR alpha signaling between tumor cells and stromal fibroblasts by soluble PDGFR alpha-IgG significantly reduced tumor growth. Thus, PDGFR alpha signaling is required for the recruitment of VEGF-producing stromal fibroblasts for tumor angiogenesis and growth. Our findings highlight a novel aspect of PDGFR alpha signaling in tumorigenesis.
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PMID:VEGF-null cells require PDGFR alpha signaling-mediated stromal fibroblast recruitment for tumorigenesis. 1522 50

We have previously observed that the synthetic peptide corresponding to amino acids 31-45 (PCK3145) of PSP94 can reduce prostate tumor growth in vivo. Moreover, a recently concluded phase IIa clinical trial with patients with hormone refractory prostate cancer indicated that PCK3145 down-regulates the levels of plasma matrix metalloproteinase (MMP)-9, a MMP involved in metastasis and tumor angiogenesis. The purpose of our study was to investigate the molecular mechanisms of action of PCK3145 and whether this peptide could antagonize tumor neovascularization. We show that, in a syngeneic in vivo model of rat prostate cancer, the expression of endothelial cell (EC) specific CD31, a marker of tumor vessel density, was decreased by 43% in PCK3145-treated animals. In vitro, PCK3145 specifically antagonized in a dose-dependent manner the VEGF-induced ERK phosphorylation as well as the phosphorylation of the VEGFR-2 in cultured EC (HUVEC). These anti-VEGF effects were partly reproduced by pharmacological inhibitors such as PD98059 and PTK787, suggesting that PCK3145 inhibits the tyrosine kinase activity associated to VEGFR-2, which in turn prevents intracellular signalling through the MAPK cascade. Moreover, PCK3145 was also found to inhibit the PDGF-induced phosphorylation of PDGFR in smooth muscle cells. Finally, PCK3145 inhibited in vitro EC tubulogenesis and VEGF-induced MMP-2 secretion suggesting its potential implication as an antiangiogenic agent. Our study demonstrates that PCK3145 interferes with the tyrosine kinase activity associated with VEGF signalling axis in EC. The antiangiogenic properties of this peptide could be highly beneficial and exploited in novel antiangiogenic therapies, for patients with various cancers.
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PMID:A prostate secretory protein94-derived synthetic peptide PCK3145 inhibits VEGF signalling in endothelial cells: implication in tumor angiogenesis. 1633 3

Activating mutations in Ras and B-RAF were identified in several human cancers. In addition, several receptor tyrosine kinases, acting upstream of Ras, were found either mutated or overexpressed in human tumors. Because oncogenic activation of the Ras/RAF pathway may lead to a sustained proliferative signal resulting in tumor growth and progression, inhibition of this pathway represents an attractive approach for cancer drug discovery. A novel class of biaryl urea that inhibits C-RAF kinase was discovered using a combination of medicinal and combinatorial chemistry approaches. This effort culminated in the identification of the clinical candidate BAY 43-9006 (Sorafenib, Nexavar), which has recently been approved by the FDA for advanced renal cell carcinoma in phase III clinical trials. Sorafenib inhibited the kinase activity of both C-RAF and B-RAF (wild type and V600E mutant). It inhibited MEK and ERK phosphorylation in various cancer cell lines and tumor xenografts and exhibited potent oral antitumor activity in a broad spectrum of human tumor xenograft models. Further characterization of sorafenib revealed that this molecule was a multikinase inhibitor that targeted the vascular endothelial growth factor receptor family (VEGFR-2 and VEGFR-3) and platelet-derived growth factor receptor family (PDGFR-beta and Kit), which play key roles in tumor progression and angiogenesis. Thus, sorafenib may inhibit tumor growth by a dual mechanism, acting either directly on the tumor (through inhibition of Raf and Kit signaling) and/or on tumor angiogenesis (through inhibition of VEGFR and PDGFR signaling). In phase I and phase II clinical trials, sorafenib showed limited side effects and, more importantly, disease stabilization. This agent is currently being evaluated in phase III clinical trials in renal cell and hepatocellular carcinomas.
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PMID:Sorafenib (BAY 43-9006, Nexavar), a dual-action inhibitor that targets RAF/MEK/ERK pathway in tumor cells and tyrosine kinases VEGFR/PDGFR in tumor vasculature. 1675 55

The PDGF pathway is essential in tumor angiogenesis. Although the expression of the PDGF receptors has been excessively studied on breast cancer cells, few studies exist on PDGFR expression on the tumor endothelial cells. In the present study, it is investigated whether endothelial PDGF receptors' expression is altered in breast cancer. Endothelial PDGFRalpha and beta expression was initially studied under the influence of tumor conditioned medium derived from a breast cancer cell line. Following tissue culture experiments the endothelial expression of both receptors was studied on formalin-fixed paraffin-embedded tissue sections of normal breast and breast cancer specimens. The tissue culture experiment revealed a possible up-regulation of endothelial PDGFRbeta by breast cancer environment. Immunohistochemistry verified the result since 69.7% of the breast cancer sections were positive for PDGFRbeta compared to 43.3% of normal breast sections (p<0.05). No statistical difference was revealed by studying PDGFRalpha expression. In conclusion, our findings support the thesis of possible anti-PDGFRbeta anti-angiogenic therapy, in cases of endothelial PDGFRbeta-expressing breast cancer.
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PMID:Expression of endothelial PDGF receptors alpha and beta in breast cancer: up-regulation of endothelial PDGF receptor beta. 1739 53

Tumors produce multiple growth factors, but little is known about the interplay between various angiogenic factors in promoting tumor angiogenesis, growth, and metastasis. Here we show that 2 angiogenic factors frequently upregulated in tumors, PDGF-BB and FGF2, synergistically promote tumor angiogenesis and pulmonary metastasis. Simultaneous overexpression of PDGF-BB and FGF2 in murine fibrosarcomas led to the formation of high-density primitive vascular plexuses, which were poorly coated with pericytes and VSMCs. Surprisingly, overexpression of PDGF-BB alone in tumor cells resulted in dissociation of VSMCs from tumor vessels and decreased recruitment of pericytes. In the absence of FGF2, capillary ECs lacked response to PDGF-BB. However, FGF2 triggers PDGFR-alpha and -beta expression at the transcriptional level in ECs, which acquire hyperresponsiveness to PDGF-BB. Similarly, PDGF-BB-treated VSMCs become responsive to FGF2 stimulation via upregulation of FGF receptor 1 (FGFR1) promoter activity. These findings demonstrate that PDGF-BB and FGF2 reciprocally increase their EC and mural cell responses, leading to disorganized neovascularization and metastasis. Our data suggest that intervention of this non-VEGF reciprocal interaction loop for the tumor vasculature could be an important therapeutic target for the treatment of cancer and metastasis.
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PMID:Angiogenic factors FGF2 and PDGF-BB synergistically promote murine tumor neovascularization and metastasis. 1790 24

Most cancers are dependent on the growth of tumor blood vessels and inhibition of tumor angiogenesis may thus provide an efficient strategy to retard or block tumor growth. Recently, tumor vascular targeting has expanded to include not only endothelial cells (ECs) but also smooth muscle cells (SMCs), which contribute to a mature and functional vasculature. We have reported previously that delphinidin, a major biologically active constituent of berries, inhibits the vascular endothelial growth factor-induced phosphorylation of vascular endothelial growth factor receptor-2 and blocks angiogenesis in vitro and in vivo. In the present study, we show that delphinidin also inhibits activation of the platelet-derived growth factor (PDGF)-BB receptor-beta [platelet-derived growth factor receptor-beta (PDGFR-beta)] in SMC and that this inhibition may contribute to its antitumor effect. The inhibitory effect of delphinidin on PDGFR-beta was very rapid and led to the inhibition of PDGF-BB-induced activation of extracellular signal-regulated kinase (ERK)-1/2 signaling and of the chemotactic motility of SMC, as well as the differentiation and stabilization of EC and SMC into capillary-like tubular structures in a three-dimensional coculture system. Using an anthocyan-rich extract of berries, we show that berry extracts were able to suppress the synergistic induction of vessel formation by basic fibroblast growth factor-2 and PDGF-BB in the mouse Matrigel plug assay. Oral administration of the berry extract also significantly retarded tumor growth in a lung carcinoma xenograft model. Taken together, these results provide new insight into the molecular mechanisms underlying the antiangiogenic activity of delphinidin that will be helpful for the development of dietary-based chemopreventive strategies.
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PMID:Delphinidin, a dietary anthocyanidin, inhibits platelet-derived growth factor ligand/receptor (PDGF/PDGFR) signaling. 1833 83

Sorafenib, an epidermal growth factor receptor inhibitor, is a novel treatment used for malignancies resistant to traditional chemotherapy. Epidermal growth factor receptors (EGFR) are a family of 4 transmembrane tyrosine kinase receptors that, via signal transduction pathways, mediate cell growth, differentiation, and survival. Sorafenib is a targeted drug specifically engineered to inhibit Raf serine/threonine kinases, which are part of the reticular activating system (RAS) oncogene pathway. In addition, in vitro studies have shown sorafenib to be a potent multikinase inhibitor, targeting receptor tyrosine kinases associated with tumor angiogenesis (VEGFR-2, VEGFR-3, and PDGFR-beta) and progression. Initially, approved for use in advanced renal cell carcinoma, sorafenib is being studied for the treatment of other solid tumors at our institution. During the clinical trial, 4 patients were referred to the dermatology clinic for evaluation and treatment of diffuse erythematous eruptions all occurring 8 to 10 days after initiating sorafenib at a dose of 400 mg twice daily. These eruptions occurred in demographically similar patients and displayed similar clinical characteristics and histopathological findings. Clinically, 3 of 4 patients had facial erythema, 3 of 4 had generalized macular erythema, 3 of 4 had widespread follicular-based papular eruption, and 4 of 4 had palmoplantar erythrodysesthesia. Half of the patients had cutaneous eruptions without systemic effects, while the other half had hypersensitivity reactions requiring withdrawal from clinical trial. This is the first case series illustrating drug eruptions induced by sorafenib.
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PMID:Cutaneous drug eruptions induced by sorafenib: a case series. 1911 7

Inhibition of tumor angiogenesis through blockade of the vascular endothelial growth factor (VEGF) signaling pathway is a new treatment modality in oncology. Preclinical findings suggest that blockade of additional pro-angiogenic kinases, such as fibroblast and platelet-derived growth factor receptors (FGFR and PDGFR), may improve the efficacy of pharmacological cancer treatment. Indolinones substituted in position 6 were identified as selective inhibitors of VEGF-, PDGF-, and FGF-receptor kinases. In particular, 6-methoxycarbonyl-substituted indolinones showed a highly favorable selectivity profile. Optimization identified potent inhibitors of VEGF-related endothelial cell proliferation with additional efficacy on pericyctes and smooth muscle cells. In contrast, no direct inhibition of tumor cell proliferation was observed. Compounds 2 (BIBF 1000) and 3 (BIBF 1120) are orally available and display encouraging efficacy in in vivo tumor models while being well tolerated. The triple angiokinase inhibitor 3 is currently in phase III clinical trials for the treatment of nonsmall cell lung cancer.
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PMID:Design, synthesis, and evaluation of indolinones as triple angiokinase inhibitors and the discovery of a highly specific 6-methoxycarbonyl-substituted indolinone (BIBF 1120). 1952 65

Tyrosine kinase receptors have important signaling functions in various physiological and pathological pathways. The recognition of their involvement in tumor angiogenesis, which is the main event of tumor progression, opened a new era in the discovery of anticancer drugs. Developers soon grasped that by targeting several tyrosine kinase receptors at once, so-called multitarget tyrosine kinase inhibitors, a drug could dramatically affect the progression of cancer and decrease resistance. Several antiangiogenic, multitarget tyrosine kinase inhibitors, such as sorafenib and sunitinib, are already marketed, while many more are undergoing clinical trials for a range of cancer types. Boehringer Ingelheim Corp is developing intedanib (BIBF-1120), a triple kinase inhibitor blocking VEGFR, PDGFR and FGFR for the treatment of several malignancies and idiopathic pulmonary fibrosis. The preliminary data for intedanib appears at least as good as that for other antiangiogenic tyrosine kinase inhibitors or other antiangiogenic approaches that are not targeting the tyrosine kinases. The sustained inhibition of VEGFR phosphorylation (> 24 h), the fast in vivo clearance and clinical efficacy against a broad range of malignancies appear to be the major advantages of intedanib. Furthermore, the existing data suggest an excellent safety profile. At the time of publication, intedanib had reached phase III trials for the treatment of NSCLC and ovarian cancer.
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PMID:Intedanib, a triple kinase inhibitor of VEGFR, FGFR and PDGFR for the treatment of cancer and idiopathic pulmonary fibrosis. 2043 91


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