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Vascular Endothelial Growth Factor Receptor (vascular + endothelial_growth_factor_receptor)

Distribution by Scientific Domains

Medical Sciences	86%
Life Sciences	8%

Distribution within Medical Sciences

Oncology & Radiotherapy	34%
Hepatology	15%

Selected Abstracts

Expression of Vascular Endothelial Growth Factor Receptors in Bovine Cystic Follicles

REPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2008
N Isobe
Contents Cystic follicles have excess fluid derived from blood flow in the theca interna of the follicle; therefore, the vasculature network is related to cystic follicle formation. Vascular endothelial growth factor (VEGF) is a potent stimulator of blood vessel permeability and angiogenesis. The aim of this study was to examine the expression of VEGF receptors proteins and mRNA in cystic follicles to elucidate the VEGF system in cystic follicles. The expression of protein for VEGF receptors; fms-like-tyrosine kinase-1 (Flt-1) and foetal liver kinase-1 (Flk-1) was detected by the immunohistochemical method. The mRNA expression of Flt-1 and Flk-1 in cystic follicles was determined by RT-PCR. Concentration of oestradiol-17, and progesterone in the follicular fluid of cystic follicles was determined using ELISA. Flt-1- and Flk-1 proteins were localized in granulosa and theca interna cells and endothelial cells of theca layers. The intensity of Flt-1 and Flk-1 immunoreaction was similar among cystic follicles with various ratios of oestradiol-17,/progesterone concentrations. The expression of Flt-1 and Flk-1 mRNA was similar, regardless of the ratio of oestradiol-17, to progesterone in follicular fluid. These results demonstrate that cystic follicles have both VEGF receptors in the granulosa and theca interna layers, which may be responsible for the increased permeability of microvessels, causing the accumulation of follicular fluid in cystic follicles. [source]

Phase I clinical trial using peptide vaccine for human vascular endothelial growth factor receptor 2 in combination with gemcitabine for patients with advanced pancreatic cancer

CANCER SCIENCE, Issue 2 2010
Motoki Miyazawa
Vascular endothelial growth factor receptor 2 (VEGFR2) is an essential factor in tumor angiogenesis and in the growth of pancreatic cancer. Immunotherapy using epitope peptide for VEGFR2 (VEGFR2-169) that we identified previously is expected to improve the clinical outcome. Therefore, a phase I clinical trial combining of VEGFR2-169 with gemcitabine was conducted for patients with advanced pancreatic cancer. Patients with metastatic and unresectable pancreatic cancer were eligible for the trial. Gemcitabine was administered at a dose of 1000 mg/m2 on days 1, 8, and 15 in a 28-day cycle. The VEGFR2-169 peptide was subcutaneously injected weekly in a dose-escalation manner (doses of 0.5, 1, and 2 mg/body, six patients/one cohort). Safety and immunological parameters were assessed. No severe adverse effect of grade 4 or higher was observed. Of the 18 patients who completed at least one course of the treatment, 15 (83%) developed immunological reactions at the injection sites. Specific cytotoxic T lymphocytes (CTL) reacting to the VEGFR2-169 peptide were induced in 11 (61%) of the 18 patients. The disease control rate was 67%, and the median overall survival time was 8.7 months. This combination therapy for pancreatic cancer patients was tolerable at all doses. Peptide-specific CTL could be induced by the VEGFR2-169 peptide vaccine at a high rate, even in combination with gemcitabine. From an immunological point of view, the optimal dose for further clinical trials might be 2 mg/body or higher. This trial was registered with ClinicalTrial.gov (no. NCT 00622622). (Cancer Sci 2009) [source]

Vascular endothelial growth factor receptor 1 expression in pelvic lymph nodes predicts the risk of cancer progression after radical prostatectomy

CANCER SCIENCE, Issue 6 2009
Kazutoshi Fujita
Recent studies suggest that vascular endothelial growth factor receptor (VEGFR) 1-positive hematopoietic progenitor cells precede the arrival of tumor cells and form clusters that may portend sites of future metastatic disease. The aim of the present study was to clarify whether VEGFR1 expression in pelvic lymph nodes predicts the risk of prostate cancer progression after radical prostatectomy. VEGFR1 expression in pelvic lymph nodes was examined by immunohistochemistry in 95 patients who underwent radical prostatectomy for prostate cancer. A cluster of VEGFR1-positive cells was considered positive. Expression of VEGFR1 in pelvic lymph nodes and biochemical recurrence after radical prostatectomy were examined by univariate survival analysis and multivariate Cox proportional hazards regression analysis. Thirty-seven of 79 lymph node-negative patients (46.8%) were found to have VEGFR1-positive cells in their pelvic lymph nodes, whereas 16 of 16 lymph node metastasis-positive patients (100%) had VEGFR1 clusters. There was a significant correlation between pathological stage and VEGFR1 staining (P = 0.002). Univariate analysis showed that pathological stage ,pT3 and VEGFR1 expression in pelvic lymph nodes were each significantly associated with biochemical recurrence after radical prostatectomy. Multivariate analysis showed VEGFR1 expression to be an independent predictor of biochemical recurrence after radical prostatectomy (risk ratio = 5.715, P = 0.010), as was preoperative prostate-specific antigen (PSA) level ,10 ng/mL. Although larger validation studies are required, our results suggest that VEGFR1 expression in pelvic lymph nodes predicts the risk of biochemical PSA recurrence after radical prostatectomy. (Cancer Sci 2009; 100: 1047,1050) [source]

Significance of phospho-vascular endothelial growth factor receptor-2 expression in pancreatic cancer

CANCER SCIENCE, Issue 6 2010
Yosuke Doi
Vascular endothelial growth factor receptors (VEGFRs) are mainly expressed by endothelial cells, but they are also expressed by some cancer cells, including pancreatic cancer. The objective of this study was to evaluate the significance of VEGFRs expression in pancreatic cancer cells. A total of 107 primary pancreatic tumors were stained with antibodies against VEGFR-1, VEGFR-2, phospho-VEGFR-2 (pVEGFR-2), VEGFR-3, VEGF-A, VEGF-C, and VEGF-D. VEGFR-2 and pVEGFR-2 expression were positive in 74 (69%) and 54 (50%) of 107 pancreatic cancers. There was a significant correlation (P < 0.001) between VEGFR-2 expression and pVEGFR-2 expression. pVEGFR-2 was significantly associated with invasion to the anterior capsule of pancreas (P = 0.032) and arterial invasion (P = 0.012). In contrast, VEGFR-1 and VEGFR-3 expression was only observed in 13 (12%) and 15 (14%) of 107 pancreatic cancers, and was not associated with any clinicopathological features. The prognosis of pVEGFR-2 positive patients with stage IIA tumors was significantly (P = 0.0441) poorer than that of pVEGFR-2-negative patients. VEGF-A, VEGF-C, and VEGF-D expression was positive in 42 (39%), 82 (77%), and 39 (36%) of 107 pancreatic cancers, respectively. The prognosis for VEGF-A-positive patients was significantly (P = 0.0425) poor, but not for VEGF-C-positive and VEGF-D-positive patients. A multivariate analysis indicated pVEGFR-2 expression to be an independent prognostic factor, but not VEGF-A. These findings suggested that VEGFR-2 signaling might therefore be associated with the prognosis of patients with pancreatic cancer. The expression of pVEGFR-2 might be a novel predictive prognostic marker for patients with pancreatic cancers, especially at clinical stage IIA. (Cancer Sci 2010) [source]

THERAPEUTIC HOTLINE: A rare vandetanib-induced photo-allergic drug eruption

DERMATOLOGIC THERAPY, Issue 5 2010
Paolo Fava
ABSTRACT Vandetanib is an inhibitor of the vascular endothelial growth factor receptor 2 tyrosine kinase and the epidermal growth factor receptor tyrosine kinase, recently used in the treatment of different tumors. We describe a case of a photo-allergic reaction to vandetanib in an 80-year-old Caucasian woman affected by metastatic non-small cell lung cancer. Phototoxic reactions to vandetanib have been rarely reported in the literature. Dermatologists should be aware of this cutaneous side effect of vandetanib treatment and affected patients should be counseled to use adequate sun protection. [source]

Growth inhibition of orthotopic anaplastic thyroid carcinoma xenografts in nude mice by PTK787/ZK222584 and CPT-11

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 5 2006
Seungwon Kim MD
Abstract Background. A preclinical evaluation of CPT-1 (Camptosar, irinotecan) and PTK787/ZK222584, a vascular endothelial growth factor receptor (VEGFR-2) tyrosine kinase inhibitor, as therapeutic agents against anaplastic thyroid carcinoma (ATC) was performed in vitro and in an orthotopic model of ATC in nude mice. Methods. The cytotoxic and cytostatic effects of CPT-11 on ATC cell lines were evaluated. The antitumor effects of CPT-11 in combination with PTK787/ZK222584 on orthotopic ATC xenografts in nude mice were also studied. Results. CPT-11 demonstrated significant antiproliferative effects on ATC cell lines. In vivo, PTK787/ZK222584, CPT-11, and the two agents together produced 61%, 82%, and 89% decrease in tumor growth, respectively. The differences in tumor volume between CPT-11 and CPT-11 + PTK787/ZK222584 groups were not statistically significant. PTK787/ZK222584 inhibited the phosphorylation of VEGFR-2 on tumor endothelium and decrease the tumor microvessel density. Conclusions. The camptothecin class of chemotherapeutic agents and antiangiogenic agents such as PTK787/ZK222584 warrant further study as novel therapeutic agents against ATC. © 2005 Wiley Periodicals, Inc. Head Neck27: 389,399, 2006 [source]

Furo[2,3- d]pyrimidines and Oxazolo[5,4- d]pyrimidines as Inhibitors of Receptor Tyrosine Kinases (RTK)

HELVETICA CHIMICA ACTA, Issue 4 2004
Andreas Martin-Kohler
Receptor tyrosine kinases such as VEGFR2 (vascular endothelial growth factor receptor 2, KDR) or EGFR (epidermal growth factor receptor) play crucial roles in a variety of diseases, such as cancer. Recently, some pyrrolopyrimidines were shown to be potent EGFR inhibitors. Therefore, new types of oxazolo[5,4- d]pyrimidines and furo[2,3- d]pyrimidines were synthesized (Schemes,1 and 2). Appropriately substituted derivatives of these classes of compounds inhibited VEGFR2 and EGFR with IC50 values in the low nanomolar range (see Table). Generally, the furopyrimidines were somewhat more active than the oxazolopyrimidines. The best inhibitors, 20m, 20p, and 20r, had an IC50 of 3,nM towards EGFR and showed a good selectivity, being distinctly less active towards VEGFR2. [source]

Molecular characterization of the vascular features of focal nodular hyperplasia and hepatocellular adenoma: A role for angiopoietin-1,

HEPATOLOGY, Issue 2 2010
Annette S. H. Gouw
Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are two hepatic nodular lesions of different etiologies. FNH, a polyclonal lesion, is assumed to be a regenerative reaction following a vascular injury, whereas HCA is a monoclonal, benign neoplastic lesion. In addition to features that are predominantly found in either FNH or HCA (e.g., dystrophic vessels in FNH and single arteries in HCA), FNH and HCA share morphological vascular abnormalities such as dilated sinusoids. We hypothesized that these anomalous vascular features are associated with altered expression of growth factors involved in vascular remodeling. This was based on reports of morphologically abnormal hepatic vasculature and nodular lesions in transgenic models of hepatocytic overexpression of angiopoietin-1 (Ang-1), a member of the angiopoietin family, which is crucially involved in vascular morphogenesis and homeostasis. We investigated gene and protein expression of members of the angiopoietin system and vascular endothelial growth factor A (VEGF-A) and its receptors in 9 FNH samples, 13 HCA samples, and 9 histologically normal livers. In comparison with normal samples, a significant increase in Ang-1 was found in FNH (P < 0.01) and HCA (P < 0.05), whereas no significant changes in Ang-2, receptor tyrosine kinase with immunoglobulin-like and EGF-like domains 2, VEGF-A, or vascular endothelial growth factor receptor 2 (VEGFR-2) were observed. Conclusion: Because of the different etiological contexts of a preceding vascular injury in FNH and a neoplastic growth in HCA, Ang-1 might exert different effects on the vasculature in these lesions. In FNH, it could predominantly stimulate recruitment of myofibroblasts and result in dystrophic vessels, whereas in HCA, it may drive vascular remodeling that produces enlarged vessels and arterial sprouting that generates single arteries. Hepatology 2010 [source]

Up-regulation of proproliferative genes and the ligand/receptor pair placental growth factor and vascular endothelial growth factor receptor 1 in hepatitis C cirrhosis

LIVER INTERNATIONAL, Issue 7 2007
Xiao X. Huang
Abstract Background/Aims: Cirrhosis can lead to hepatocellular carcinoma (HCC). Non-diseased liver and hepatitis C virus (HCV)-associated cirrhosis with or without HCC were compared. Method: Proliferation pathway genes, immune response genes and oncogenes were analysed by a quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and immunostaining. Results: Real-time RT-PCR showed up-regulation of genes in HCV cirrhosis including the proliferation-associated genes bone morphogenetic protein 3 (BMP3), placental growth factor 3 (PGF3), vascular endothelial growth factor receptor 1 (VEGFR1) and soluble VEGFR1, the oncogene FYN, and the immune response-associated genes toll-like receptor 9 (TLR9) and natural killer cell transcript 4 (NK4). Expressions of TLR2 and the oncogenes B-cell CLL/lymphoma 9 (BCL9) and PIM2 were decreased in HCV cirrhosis. In addition, PIM2 and TLR2 were increased in HCV cirrhosis with HCC compared with HCV cirrhosis. The ligand/receptor pair PGF and VEGFR1 was intensely expressed by the portal tract vascular endothelium. VEGFR1 was expressed in reactive biliary epithelial structures in fibrotic septum and in some stellate cells and macrophages. Conclusion: PGF and VEGFR1 may have an important role in the pathogenesis of the neovascular response in cirrhosis. [source]

Early onset preeclampsia and second trimester serum markers

PRENATAL DIAGNOSIS, Issue 12 2009
Geralyn M. Lambert-Messerlian
Abstract Objective To examine serum markers measured in the second trimester to identify women who subsequently develop preeclampsia. Methods Clinically defined preeclampsia was confirmed in 45 women who had provided a serum sample as part of Down syndrome screening. Preeclampsia was categorized as mild or severe, as well as early (<32 weeks) or late onset. Each case was matched with five controls based on gestational age and date of serum collection. Stored sera were retrieved and tested for inhibin A, soluble vascular endothelial growth factor receptor 1 (sVEGF R1), placental growth factor (PlGF), and endoglin. Results were converted to multiples of the median (MoM) and compared in case and control pregnancies. Univariate analysis was used to identify the strongest markers, which were then used in a multivariate model. Results Inhibin A, PlGF, and endoglin were consistently associated with preeclampsia, especially for early onset disease. A multivariate model using the three markers could identify 50% of the pregnancies with early onset preeclampsia with a 2% false positive rate. Conclusion The levels of inhibin A, PlGF, and endoglin in the second trimester can be combined using a predictive model to provide individualized risk estimates for early onset preeclampsia. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Effect of Polymorphisms in Four Candidate Genes for Fertility on Litter Size in a German Pig Line

REPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2010
A Spötter
Contents We carried out an SNP discovery project in pigs for candidate genes playing potentially important roles in embryonic development. Using eight pigs one each from eight breeds (Meishan, Mangalitza, Duroc, Pietrain, German Landrace, Hampshire, Husum Red Pied, German Large White), 36 SNPs were identified in intronic sequences of 21 porcine candidate genes based on sequencing of PCR products. The primer pairs were designed using porcine EST sequences allowing amplification of introns. These SNPs were tested for their association with the number of piglets born alive in German Large White sows using a discordant approach. Significant effects (p < 0.001 and p < 0.05, respectively) of intronic SNPs on litter size were found for four genes: mitogen-activated protein kinase kinase kinase 3 (MAP3K3), vascular endothelial growth factor receptor (KDR), erbb2 interacting protein (ERBB2IP) and peroxisome proliferator-activated receptor delta (PPARD). These SNPs can be further tested in upcoming association studies for their influence on litter size in different breeds using larger sample sizes. [source]

Hind-limb paraparesis in a rat model for neurolathyrism associated with apoptosis and an impaired vascular endothelial growth factor system in the spinal cord

THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2010
Kuniko Kusama-Eguchi
Abstract Neurolathyrism is a motor neuron disease characterized by lower limb paraparesis. It is associated with ingestion of a plant excitotoxin, ,-N-oxalyl-L-,,-diaminopropionic acid (L -,-ODAP), an agonist of ,-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate-type glutamatergic receptors. Previously, a limited model of neurolathyrism was reported for the rat. To improve upon the model, we stressed rat pups by separation from their mothers, followed by the subcutaneous L -,-ODAP treatment, resulting in a 4.6-fold higher incidence (14.0,15.6%) of the paraparesis compared with the prior study. The number and size of motor neurons in these rats were decreased only in the lumbar and sacral cord segments, at approximately 13,36 weeks after treatment. Only lumbar and sacral spinal cord tissue revealed pathological insults typical of physical and ischemic spinal cord injury in the surviving motor neurons. In addition, extensive but transient hemorrhage occurred in the ventral spinal cord parenchyma of the rat, and numerous TdT-mediated dUTP-biotin nick end-labeling (TUNEL)-positive cells were also observed. In parallel, vascular endothelial growth factor receptor (VEGFR)-2 (Flk-1) levels were significantly lowered in the lumbosacral spinal cord of the paraparetic rats compared with their controls, suggesting a failure of the VEGF system to protect neurons against L -,-ODAP toxicity. We propose, based on these data, a novel pathological process of motor neuron death induced by peripheral L -,-ODAP. For the first time, we present a model of the early molecular events that occur during chemically induced spinal cord injury, which can potentially be applied to other neurodegenerative disorders. J. Comp. Neurol. 518:928,942, 2010. © 2009 Wiley-Liss, Inc. [source]

Endothelial injury and repair in systemic vasculitis of the young

ARTHRITIS & RHEUMATISM, Issue 6 2010
L. A. Clarke
Objective Endothelial injury is central to the pathogenesis of vasculitis. The purpose of this study was to assess how indices of endothelial injury and repair change during different stages of disease activity in children with primary systemic vasculitis (PSV). Methods Fifty children with PSV, 17 children with nonvasculitic inflammatory diseases (pediatric inflammatory disease controls), 35 healthy age- and sex-matched pediatric controls, and 27 healthy adult controls were included in the study. Biomarkers examined were endothelial microparticles (EMPs), circulating endothelial cells (CECs), angiogenic growth factors, and endothelial progenitor cells (EPCs). EMP binding to annexin V, EMPs expressing CD144 or E-selectin, and EPCs expressing vascular endothelial growth factor receptor 2 (VEGFR-2), CD133, and CD34 were examined by flow cytometry. CECs were enumerated using immunomagnetic bead extraction techniques, and VEGF and angiopoietin 2 (Ang-2) were measured by enzyme-linked immunosorbent assay. Results Levels of CD144+ EMPs, CECs, VEGF, and EPCs were all significantly elevated in children with active vasculitis as compared with healthy children, and the levels declined with remission-inducing therapy in the individual patients. Treatment-naive patients with active disease had significantly higher levels of VEGF and Ang-2 than did those with active disease who were receiving treatment, although the levels of CECs and EMPs remained high in both of these groups. Conclusion Elevation of the levels of CECs, EMPS, EPCs, VEGF, and Ang-2 occurs during active vasculitis in children. EPC responses to active vasculitis are different in children as compared with that observed in adults with vasculitis, and both CECs and EMPs can be used to monitor disease activity in children with vasculitis. [source]

Anti,neuropilin-1 peptide inhibition of synoviocyte survival, angiogenesis, and experimental arthritis

ARTHRITIS & RHEUMATISM, Issue 1 2010
Jin-Sun Kong
Objective To delineate the role of neuropilin-1 (NP-1), a vascular endothelial growth factor receptor (VEGFR), in rheumatoid inflammation and to determine whether blockade of NP-1 could suppress synoviocyte survival and angiogenesis. Methods VEGF111,165 peptide, which encompasses the NP-1 binding domain of VEGF165, was generated by cleaving VEGF165 with plasmin. The effect of this peptide on the interaction between VEGF165 and its receptor was determined by 125I-VEGFR binding assay. Assays to determine synoviocyte apoptosis, adhesion, and migration were performed in the presence of VEGF165 and/or the peptide. VEGF165 -induced angiogenesis was assessed by measuring the proliferation, tube formation, and wounding migration of endothelial cells (ECs). Mice were immunized with type II collagen to induce experimental arthritis. Results VEGF111,165 peptide specifically inhibited the binding of 125I-VEGF165 to NP-1 on rheumatoid synoviocytes and ECs. The peptide eliminated the VEGF165 -mediated increase in synoviocyte survival and activation of p-ERK and Bcl-2. The peptide also completely inhibited a VEGF165 -induced increase in synoviocyte adhesion and migration. In addition, the anti,NP-1 peptide blocked VEGF165 -stimulated proliferation, capillary tube formation, and wounding migration of ECs in vitro. VEGF165 -induced neovascularization in a Matrigel plug in mice was also blocked by treatment with the peptide. Finally, subcutaneous injection of anti,NP-1 peptide suppressed arthritis severity and autoantibody formation in mice with experimental arthritis and inhibited synoviocyte hyperplasia and angiogenesis in arthritic joints. Conclusion Anti,NP-1 peptide suppressed VEGF165 -induced increases in synoviocyte survival and angiogenesis, and thereby blocked experimental arthritis. Our findings suggest that anti,NP-1 peptide could be useful in alleviating chronic arthritis. [source]

Inhibition of lymphangiogenesis and lymphatic drainage via vascular endothelial growth factor receptor 3 blockade increases the severity of inflammation in a mouse model of chronic inflammatory arthritis

ARTHRITIS & RHEUMATISM, Issue 9 2009
Ruolin Guo
Objective This study was undertaken to investigate the effect of lymphatic inhibition on joint and draining lymph node (LN) pathology during the course of arthritis progression in mice. Methods Tumor necrosis factor (TNF),transgenic mice were used as a model of chronic inflammatory arthritis. Mice were subjected to contrast-enhanced magnetic resonance imaging to obtain ankle and knee joint synovial volumes and draining popliteal LN volumes before and after 8 weeks of treatment with vascular endothelial growth factor receptor 3 (VEGFR-3) neutralizing antibody, VEGFR-2 neutralizing antibody, or isotype IgG. Animals were subjected to near-infrared lymphatic imaging to determine the effect of VEGFR-3 neutralization on lymph transport from paws to draining popliteal LNs. Histologic, immunohistochemical, and reverse transcriptase,polymerase chain reaction analyses were used to examine lymphatic vessel formation and the morphology of joints and popliteal LNs. Results Compared with IgG treatment, VEGFR-3 neutralizing antibody treatment significantly decreased the size of popliteal LNs, the number of lymphatic vessels in joints and popliteal LNs, lymphatic drainage from paws to popliteal LNs, and the number of VEGF-C,expressing CD11b+ myeloid cells in popliteal LNs. However, it increased the synovial volume and area of inflammation in ankle and knee joints. VEGFR-2 neutralizing antibody, in contrast, inhibited both lymphangiogenesis and joint inflammation. Conclusion These findings indicate that lymphangiogenesis and lymphatic drainage are reciprocally related to the severity of joint lesions during the development of chronic arthritis. Lymphatic drainage plays a beneficial role in controlling the progression of chronic inflammation. [source]

Phase I pharmacokinetic study of the vascular endothelial growth factor receptor tyrosine kinase inhibitor vatalanib (PTK787) plus imatinib and hydroxyurea for malignant glioma

CANCER, Issue 10 2009
David A. Reardon MD
Abstract BACKGROUND: This study determined the maximum tolerated dose (MTD) and dose-limiting toxicities (DLT) of the oral vascular endothelial growth factor receptor (VEGFR) inhibitor, vatalanib, when administered with imatinib and hydroxyurea on a continuous daily schedule among recurrent malignant glioma patients. METHODS: All patients received 500 mg of hydroxyurea twice daily. Imatinib was dosed at 400 mg per day for patients not taking enzyme-inducing antiepileptic drugs (EIAEDs; stratum A) and at 500 mg twice-a-day for patients taking EIAEDs (stratum B). Vatalanib was escalated from 500 mg to 1250 mg twice daily in successive cohorts, independently for each stratum. Pharmacokinetics of each drug were assessed. RESULTS: A total of 37 recurrent patients, 34 (92%) with glioblastoma and 3 (8%) with grade 3 malignant glioma, were enrolled. Nineteen patients (51%) were taking EIAEDs. The MTD of vatalanib for all patients was 1000 mg twice-a-day. DLTs were hematologic, gastrointestinal, renal, and hepatic. No patients developed intracranial hemorrhage. Concurrent administration of imatinib and hydroxyurea did not affect vatalanib exposure, but EIAEDs decreased vatalanib and imatinib plasma exposures. CONCLUSIONS: Vatalanib doses up to 1000 mg twice-a-day combined with imatinib and hydroxyurea were well tolerated. Strategies to target tumor blood vessel endothelial cells and pericytes by inhibiting VEGFR and platelet-derived growth factor, respectively, were safe among recurrent malignant glioma patients and may enhance antiangiogenesis activity. Cancer 2009. © 2009 American Cancer Society. [source]

Phase I clinical trial using peptide vaccine for human vascular endothelial growth factor receptor 2 in combination with gemcitabine for patients with advanced pancreatic cancer

Vascular endothelial growth factor receptor 1 expression in pelvic lymph nodes predicts the risk of cancer progression after radical prostatectomy

Aberrant methylation of the vascular endothelial growth factor receptor-1 gene in prostate cancer

CANCER SCIENCE, Issue 6 2003
Yasushi Yamada
Transcriptional silencing of cancer-related genes by DNA methylation is observed in various cancers. To identify genes controlled by methylation in prostate cancer, we used cDNA microarray analysis to investigate gene expression in prostate cancer cell lines LNCaP and DU145 treated with a methyltransferase inhibitor alone or together with a histone deacetylase inhibitor. We detected significant changes (3.4,5.7%) in gene expression in prostate cancer cell lines with the drug treatments. Among the affected genes, that for the vascular endothelial growth factor receptor 1 (VEGFR-1) was re-expressed in LNCaP and DU145 after the drug treatments. Bisulfite sequencing revealed the promoter and exon 1 of the VEGFR-1 to be hypermethylated in the cell lines. These results support the idea that methylation is associated with loss of VEGFR-1 mRNA expression in prostate cancer cell lines. Combined bisulfite restriction analysis (COBRA) showed the gene to be methylated in 24 (38.1%) of 63 primary local prostate cancer samples, while in all 13 benign prostate samples it was not. These findings indicate that methylation of VEGFR-1 is related with prostatic carcinogenesis. [source]

Amplification of genes encoding KIT, PDGFR, and VEGFR2 receptor tyrosine kinases is frequent in glioblastoma multiforme

THE JOURNAL OF PATHOLOGY, Issue 2 2005
Heikki Joensuu
Abstract KIT, platelet-derived growth factor receptors (PDGFRs) and vascular endothelial growth factor receptors (VEGFRs) are important clinical targets for tyrosine kinase inhibitors. The frequency of KIT and VEGFR2 amplification in glioblastomas is not known, and few data are available in any other human tumour type. We investigated 43 primary glioblastomas for KIT, VEGFR2, PDGFRA and EGFR amplification using fluorescence in situ hybridization. KIT was amplified in 47% and VEGFR2 in 39% of the glioblastomas, respectively, and PDGFRA in 29%. Thirty-five (81%) of the tumours had either KIT or EGFR amplification. KIT, PDGFRA and VEGFR2 amplifications were strongly associated (p < 0.0001 for each pairwise comparison), suggesting co-amplification, whereas no significant association was found with EGFR amplification. The four secondary glioblastomas arising from pre-existing lower grade astrocytic tumours investigated had KIT amplification but none had EGFR amplification. No mutations were detected with denaturing high-performance liquid chromatography in KIT exons 9, 11, 13 or 17, PDGFRA exons 12 and 18, or EGFR exons 18, 19 or 21. Glioblastomas with KIT, PDGFR or VEGFR2 amplification were associated with similar outcome to other glioblastomas. We conclude that KIT, PDGFRA and VEGFR2 are commonly amplified in primary glioblastoma and that they may also be amplified in secondary glioblastoma. Amplified kinases may be potential targets for tyrosine kinase inhibitor therapy. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source]

Impairment of endothelial cell differentiation from bone marrow,derived mesenchymal stem cells: New insight into the pathogenesis of systemic sclerosis

ARTHRITIS & RHEUMATISM, Issue 6 2007
P. Cipriani
Objective Systemic sclerosis (SSc) is a disorder characterized by vascular damage and fibrosis of the skin and internal organs. Despite marked tissue hypoxia, there is no evidence of compensatory angiogenesis. The ability of mesenchymal stem cells (MSCs) to differentiate into endothelial cells was recently demonstrated. The aim of this study was to determine whether impaired differentiation of MSCs into endothelial cells in SSc might contribute to disease pathogenesis by decreasing endothelial repair. Methods MSCs obtained from 7 SSc patients and 15 healthy controls were characterized. The number of colony-forming unit,fibroblastoid colonies was determined. After culture in endothelial-specific medium, the endothelial-like MSC (EL-MSC) phenotype was assessed according to the surface expression of vascular endothelial growth factor receptors (VEGFRs). Senescence, chemoinvasion, and capillary morphogenesis studies were also performed. Results MSCs from SSc patients displayed the same phenotype and clonogenic activity as those from controls. In SSc MSCs, a decreased percentage of VEGFR-2+, CXCR4+, VEGFR-2+/CXCR4+ cells and early senescence was detected. After culturing, SSc EL-MSCs showed increased expression of VEGFR-1, VEGFR-2, and CXCR4, did not express CD31 or annexin V, and showed significantly decreased migration after specific stimuli. Moreover, the addition of VEGF and stromal cell,derived factor 1 to cultured SSc EL-MSCs increased their angiogenic potential less than that in controls. Conclusion Our data strongly suggest that endothelial repair may be affected in SSc. The possibility that endothelial progenitor cells could be used to increase vessel growth in chronic ischemic tissues may open up new avenues in the treatment of vascular damage caused by SSc. [source]