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1.
J Biol Chem ; 292(25): 10490-10519, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28389561

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive clinical syndrome of fatal outcome. The lack of information about the signaling pathways that sustain fibrosis and the myofibroblast phenotype has prevented the development of targeted therapies for IPF. Our previous study showed that isolated fibrogenic lung fibroblasts have high endogenous levels of the hyaluronan receptor, CD44V6 (CD44 variant containing exon 6), which enhances the TGFß1 autocrine signaling and induces fibroblasts to transdifferentiate into myofibroblasts. NADPH oxidase 4 (NOX4) enzyme, which catalyzes the reduction of O2 to hydrogen peroxide (H2O2), has been implicated in the cardiac and lung myofibroblast phenotype. However, whether CD44V6 regulates NOX4 to mediate tissue repair and fibrogenesis is not well-defined. The present study assessed the mechanism of how TGF-ß-1-induced CD44V6 regulates the NOX4/reactive oxygen species (ROS) signaling that mediates the myofibroblast differentiation. Specifically, we found that NOX4/ROS regulates hyaluronan synthesis and the transcription of CD44V6 via an effect upon AP-1 activity. Further, CD44V6 is part of a positive-feedback loop with TGFß1/TGFßRI signaling that acts to increase NOX4/ROS production, which is required for myofibroblast differentiation, myofibroblast differentiation, myofibroblast extracellular matrix production, myofibroblast invasion, and myofibroblast contractility. Both NOX4 and CD44v6 are up-regulated in the lungs of mice subjected to experimental lung injury and in cases of human IPF. Genetic (CD44v6 shRNA) or a small molecule inhibitor (CD44v6 peptide) targeting of CD44v6 abrogates fibrogenesis in murine models of lung injury. These studies support a function for CD44V6 in lung fibrosis and offer proof of concept for therapeutic targeting of CD44V6 in lung fibrosis disorders.


Assuntos
Comunicação Autócrina , Receptores de Hialuronatos/biossíntese , Fibrose Pulmonar Idiopática/metabolismo , Miofibroblastos/metabolismo , NADPH Oxidases/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Animais , Diferenciação Celular/genética , Modelos Animais de Doenças , Feminino , Humanos , Receptores de Hialuronatos/genética , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/patologia , Masculino , Camundongos , Miofibroblastos/patologia , NADPH Oxidase 4 , NADPH Oxidases/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Fator de Crescimento Transformador beta1/genética
2.
J Immunol ; 189(8): 4123-34, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22962687

RESUMO

SB1578 is a novel, orally bioavailable JAK2 inhibitor with specificity for JAK2 within the JAK family and also potent activity against FLT3 and c-Fms. These three tyrosine kinases play a pivotal role in activation of pathways that underlie the pathogenesis of rheumatoid arthritis. SB1578 blocks the activation of these kinases and their downstream signaling in pertinent cells, leading to inhibition of pathological cellular responses. The biochemical and cellular activities of SB1578 translate into its high efficacy in two rodent models of arthritis. SB1578 not only prevents the onset of arthritis but is also potent in treating established disease in collagen-induced arthritis mice with beneficial effects on histopathological parameters of bone resorption and cartilage damage. SB1578 abrogates the inflammatory response and prevents the infiltration of macrophages and neutrophils into affected joints. It also leads to inhibition of Ag-presenting dendritic cells and inhibits the autoimmune component of the disease. In summary, SB1578 has a unique kinase spectrum, and its pharmacological profile provides a strong rationale for the ongoing clinical development in autoimmune diseases.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Experimental/imunologia , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Janus Quinase 2/antagonistas & inibidores , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Artrite Experimental/patologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Modelos Animais de Doenças , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Endogâmicos Lew
3.
Chembiochem ; 14(18): 2512-8, 2013 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-24222525

RESUMO

Cellular behaviors are governed by combinations of systemic and microenvironmental factors; together, these regulate cell signaling responses to growth factors. This contextual microenvironmental influence also determines drug sensitivity. Hence using in vitro systems that model contextual cellular behavior is highly beneficial for effective therapeutic development. Angiogenesis (formation of blood vessels) is driven by a series of dynamic endothelial cell signaling responses to growth factors under the influence of the vascular extracellular matrix and adjacent pericytes. In vitro primary human vascular cell co-cultures self-assemble into capillary-like structures through reciprocal heterotypic interactions that mimic angiogenic context dynamics. By using temporal live-cell imaging-based analysis, unique angiogenic microenvironments can be delineated to quantify the contextual activity of compound inhibitors. We used this in vitro organotypic contextual screening approach to conduct structure-activity relationship analysis on a combretastatin A-4 analogue series to identify novel compounds with potent vascular disrupting activity in vivo.


Assuntos
Inibidores da Angiogênese/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores da Angiogênese/química , Animais , Linhagem Celular , Técnicas de Cocultura/métodos , Células Endoteliais da Veia Umbilical Humana , Humanos , Artéria Pulmonar/citologia , Relação Estrutura-Atividade , Peixe-Zebra
4.
Bioorg Med Chem Lett ; 22(8): 2880-4, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22437109

RESUMO

A series of 2-anilino substituted 4-aryl-8H-purines were prepared as potent inhibitors of PDK1, a serine-threonine kinase thought to play a role in the PI3K/Akt signaling pathway, a key mediator of cancer cell growth, survival and tumorigenesis. The synthesis, SAR and ADME properties of this series of compounds are discussed culminating in the discovery of compound 6 which possessed sub-micromolar cell proliferation activity and 65% oral bioavailability in mice.


Assuntos
Compostos de Anilina/química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Purinas/química , Bibliotecas de Moléculas Pequenas/química , Compostos de Anilina/farmacologia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Purinas/farmacologia , Piruvato Desidrogenase Quinase de Transferência de Acetil , Bibliotecas de Moléculas Pequenas/farmacologia , Solubilidade
6.
Cancer Cell ; 1(3): 257-67, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12086862

RESUMO

Striking homology between signaling molecules in zebrafish and humans suggests that compounds known to inhibit human kinases may enable a chemical genetic approach to dissect signaling pathways in the zebrafish embryo. We tested this hypothesis using a vascular endothelial growth factor receptor inhibitor, PTK787/ZK222584. Zebrafish embryos treated with this compound lacked all major blood vessels. Overexpression of AKT/PKB, a putative effector of vascular endothelial growth factor signaling, allowed blood vessels to form in the presence of drug. Endothelial cell apoptosis induced by the drug is prevented by increasing AKT/PKB activity, thus establishing the physiological relevance of AKT/PKB in the angiogenic process. This approach allowed us to examine the effects of blood flow and the role of endothelial signals in organogenesis.


Assuntos
Embrião não Mamífero/irrigação sanguínea , Neovascularização Fisiológica/fisiologia , Proteínas Serina-Treonina Quinases , Piridinas , Transdução de Sinais/fisiologia , Peixe-Zebra/embriologia , Sequência de Aminoácidos , Inibidores da Angiogênese/farmacologia , Animais , DNA Complementar , Endotélio Vascular/citologia , Inibidores Enzimáticos/farmacologia , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Dados de Sequência Molecular , Ftalazinas/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , RNA/metabolismo , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/antagonistas & inibidores , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Homologia de Sequência de Aminoácidos , Regulação para Cima
7.
Angiogenesis ; 13(3): 259-67, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20803239

RESUMO

EphB4 and its cognitive ligand ephrinB2 play an important role in embryonic vessel development and vascular remodeling. In addition, several reports suggest that this receptor ligand pair is also involved in pathologic vessel formation in adults including tumor angiogenesis. Eph/ephrin signaling is a complex phenomena characterized by receptor forward signaling through the tyrosine kinase of the receptor and ephrin reverse signaling through various protein-protein interaction domains and phosphorylation motifs of the ephrin ligands. Therefore, interfering with EphR/ephrin signaling by the means of targeted gene ablation, soluble receptors, dominant negative mutants or antisense molecules often does not allow to discriminate between inhibition of Eph/ephrin forward and reverse signaling. We developed a specific small molecular weight kinase inhibitor of the EphB4 kinase, NVP-BHG712, which inhibits EphB4 kinase activity in the low nanomolar range in cellular assays showed high selectivity for targeting the EphB4 kinase when profiled against other kinases in biochemical as well as in cell based assays. Furthermore, NVP-BHG712 shows excellent pharmacokinetic properties and potently inhibits EphB4 autophosphorylation in tissues after oral administration. In vivo, NVP-BHG712 inhibits VEGF driven vessel formation, while it has only little effects on VEGF receptor (VEGFR) activity in vitro or in cellular assays. The data shown here suggest a close cross talk between the VEGFR and EphR signaling during vessel formation. In addition to its established function in vascular remodeling and endothelial arterio-venous differentiation, EphB4 forward signaling appears to be an important mediator of VEGF induced angiogenesis since inhibition of EphB4 forward signaling is sufficient to inhibit VEGF induced angiogenesis.


Assuntos
Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Receptor EphB4/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacocinética , Animais , Bioensaio , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos , Neovascularização Patológica/enzimologia , Tamanho do Órgão/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Pirazóis/química , Pirazóis/farmacocinética , Pirimidinas/química , Pirimidinas/farmacocinética , Receptor EphB4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Solubilidade/efeitos dos fármacos
8.
Clin Cancer Res ; 15(5): 1612-22, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19223496

RESUMO

PURPOSE: Comparison of the antiangiogenic/vascular properties of the oral mammalian target of rapamycin (mTOR) inhibitor RAD001 (everolimus) and the vascular endothelial growth factor receptor (VEGFR) inhibitor vatalanib (PTK/ZK). EXPERIMENTAL DESIGN: Antiproliferative activity against various tumor histotypes and downstream effects on the mTOR pathway were measured in vitro. In vivo, antitumor activity, plasma, and tumor RAD001 levels were measured. Activity in several different angiogenic/vascular assays in vitro and in vivo was assessed and compared with PTK/ZK. RESULTS: RAD001 inhibited proliferation in vitro (IC50 values<1 nmol/L to >1 micromol/L), and in sensitive and insensitive tumor cells, pS6 kinase and 4E-BP1 were inhibited. Activity in vitro did not correlate with activity in vivo and significant responses were seen in tumors with IC50 values>10-fold higher than tumor RAD001 concentrations. In vitro, RAD001 inhibited the proliferation of VEGF-stimulated and fibroblast growth factor-stimulated human endothelial cells but not dermal fibroblasts and impaired VEGF release from both sensitive and insensitive tumor cells but did not inhibit migration of human endothelial cells. In vivo, in tumor models derived from either sensitive or insensitive cells, RAD001 reduced Tie-2 levels, the amount of mature and immature vessels, total plasma, and tumor VEGF. RAD001 did not affect blood vessel leakiness in normal vasculature acutely exposed to VEGF nor did it affect tumor vascular permeability (Ktrans) as measured by dynamic contrast-enhanced magnetic resonance imaging. However, the pan-VEGFR inhibitor PTK/ZK inhibited endothelial cell migration and vascular permeability but had less effect on mature vessels compared with RAD001. CONCLUSIONS: VEGFR and mTOR inhibitors show similar but also distinct effects on tumor vascular biology, which has implications for their clinical activity alone or in combination.


Assuntos
Inibidores da Angiogênese/farmacologia , Neoplasias Experimentais/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Ftalazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/química , Piridinas/farmacologia , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Sirolimo/análogos & derivados , Inibidores da Angiogênese/farmacocinética , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Everolimo , Feminino , Humanos , Técnicas Imunoenzimáticas , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Ftalazinas/farmacocinética , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Quinases/metabolismo , Piridinas/farmacocinética , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos WF , Receptor TIE-2/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Sirolimo/farmacocinética , Sirolimo/farmacologia , Serina-Treonina Quinases TOR , Distribuição Tecidual , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Mol Cancer Ther ; 8(1): 55-63, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19139113

RESUMO

Halting tumor growth by interfering with tumor-induced angiogenesis is an attractive therapeutic approach. Such treatments include humanized antibodies blocking the activity of vascular endothelial growth factor (VEGF)-A (bevacizumab), soluble VEGF receptor (VEGFR) constructs (VEGF-Trap), or small-molecule inhibitors of VEGFR signaling, including PTK787/ZK222584 (PTK/ZK), sorafenib, and sunitinib. PTK/ZK has been shown previously to specifically block VEGF-induced phosphorylation of VEGFR-1, -2 and -3 and thereby to inhibit endothelial cell proliferation, differentiation, and tumor angiogenesis. We have investigated the effect of PTK/ZK on tumor angiogenesis and tumor lymphangiogenesis using the Rip1Tag2 transgenic mouse model of pancreatic beta cell carcinogenesis. In Rip1Tag2 mice, tumor angiogenesis is predominantly mediated by VEGF-A, and as expected, PTK/ZK efficiently impaired tumor blood vessel angiogenesis and tumor growth. Double-transgenic Rip1Tag2;Rip1VEGF-C and Rip1Tag2;Rip1VEGF-D mice not only exhibit VEGF-A-dependent blood vessel angiogenesis but also tumor lymphangiogenesis induced by the transgenic expression of VEGF-C or -D. In these mouse models, PTK/ZK also repressed tumor blood vessel angiogenesis and tumor growth yet failed to affect tumor lymphangiogenesis and lymphogenic metastasis. Adenoviral delivery of soluble VEGFR-3 also did not prevent tumor lymphangiogenesis in these mice. In contrast, spontaneous tumor lymphangiogenesis, as observed by the stochastic expression of VEGF-C and -D in tumors of neural cell adhesion molecule-deficient Rip1Tag2 mice, was repressed by PTK/ZK and soluble VEGFR-3. The results indicate that the time of onset and the levels of VEGF-C/D expression may be critical variables in efficiently repressing tumor lymphangiogenesis and that pathways other than VEGFR signaling may be involved in tumor lymphangiogenesis.


Assuntos
Linfangiogênese/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Ftalazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Progressão da Doença , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/irrigação sanguínea , Neoplasias/enzimologia , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo
10.
Am J Pathol ; 173(4): 1173-85, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18787105

RESUMO

Inhibitors of angiogenesis and radiation induce compensatory changes in the tumor vasculature both during and after treatment cessation. To assess the responses to irradiation and vascular endothelial growth factor-receptor tyrosine kinase inhibition (by the vascular endothelial growth factor tyrosine kinase inhibitor PTK787/ZK222854), mammary carcinoma allografts were investigated by vascular casting; electron, light, and confocal microscopy; and immunoblotting. Irradiation and anti-angiogenic therapy had similar effects on the tumor vasculature. Both treatments reduced tumor vascularization, particularly in the tumor medulla. After cessation of therapy, the tumor vasculature expanded predominantly by intussusception with a plexus composed of enlarged sinusoidal-like vessels containing multiple transluminal tissue pillars. Tumor revascularization originated from preserved alpha-smooth muscle actin-positive vessels in the tumor cortex. Quantification revealed that recovery was characterized by an angiogenic switch from sprouting to intussusception. Up-regulated alpha-smooth muscle actin-expression during recovery reflected the recruitment of alpha-smooth muscle actin-positive cells for intussusception as part of the angio-adaptive mechanism. Tumor recovery was associated with a dramatic decrease (by 30% to 40%) in the intratumoral microvascular density, probably as a result of intussusceptive pruning and, surprisingly, with only a minimal reduction of the total microvascular (exchange) area. Therefore, the vascular supply to the tumor was not severely compromised, as demonstrated by hypoxia-inducible factor-1alpha expression. Both irradiation and anti-angiogenic therapy cause a switch from sprouting to intussusceptive angiogenesis, representing an escape mechanism and accounting for the development of resistance, as well as rapid recovery, after cessation of therapy.


Assuntos
Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/terapia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/radioterapia , Ftalazinas/uso terapêutico , Piridinas/uso terapêutico , Radiação Ionizante , Actinas/metabolismo , Animais , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Imuno-Histoquímica , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/ultraestrutura , Camundongos , Camundongos Nus , Necrose , Molécula-1 de Adesão Celular Endotelial a Plaquetas , Fatores de Tempo , Sobrevivência de Tecidos/efeitos dos fármacos , Sobrevivência de Tecidos/efeitos da radiação , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/efeitos da radiação , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Bioorg Med Chem Lett ; 19(16): 4863-7, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19615901

RESUMO

Novel nonpeptide small molecule renin inhibitors bearing an N-isopropyl P(1) motif were designed based on initial lead structures 1 and aliskiren (2). (P(3)-P(1))-Benzamide derivatives such as 9a and 34, as well as the corresponding P(1) basic tertiary amine derivatives 10 and 35 were found to display low nanomolar inhibition against human renin in vitro.


Assuntos
Amidas/química , Anti-Hipertensivos/química , Benzamidas/química , Etilenos/química , Fumaratos/química , Inibidores de Proteases/química , Renina/antagonistas & inibidores , Administração Oral , Animais , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/farmacologia , Benzamidas/síntese química , Benzamidas/farmacologia , Callithrix , Humanos , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacologia , Renina/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
12.
Cancer Res ; 66(1): 221-31, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16397235

RESUMO

FTY720, a potent immunomodulator, becomes phosphorylated in vivo (FTY-P) and interacts with sphingosine-1-phosphate (S1P) receptors. Recent studies showed that FTY-P affects vascular endothelial growth factor (VEGF)-induced vascular permeability, an important aspect of angiogenesis. We show here that FTY720 has antiangiogenic activity, potently abrogating VEGF- and S1P-induced angiogenesis in vivo in growth factor implant and corneal models. FTY720 administration tended to inhibit primary and significantly inhibited metastatic tumor growth in a mouse model of melanoma growth. In combination with a VEGFR tyrosine kinase inhibitor PTK787/ZK222584, FTY720 showed some additional benefit. FTY720 markedly inhibited tumor-associated angiogenesis, and this was accompanied by decreased tumor cell proliferation and increased apoptosis. In transfected HEK293 cells, FTY-P internalized S1P1 receptors, inhibited their recycling to the cell surface, and desensitized S1P receptor function. Both FTY720 and FTY-P apparently failed to impede VEGF-produced increases in mitogen-activated protein kinase activity in human umbilical vascular endothelial cells (HUVEC), and unlike its activity in causing S1PR internalization, FTY-P did not result in a decrease of surface VEGFR2 levels in HUVEC cells. Pretreatment with FTY720 or FTY-P prevented S1P-induced Ca2+ mobilization and migration in vascular endothelial cells. These data show that functional antagonism of vascular S1P receptors by FTY720 potently inhibits angiogenesis; therefore, this may provide a novel therapeutic approach for pathologic conditions with dysregulated angiogenesis.


Assuntos
Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/tratamento farmacológico , Propilenoglicóis/farmacologia , Receptores de Lisoesfingolipídeo/antagonistas & inibidores , Animais , Cálcio/metabolismo , Processos de Crescimento Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Córnea/irrigação sanguínea , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Feminino , Cloridrato de Fingolimode , Humanos , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Fosforilação , Ftalazinas/farmacologia , Propilenoglicóis/farmacocinética , Piridinas/farmacologia , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/análogos & derivados , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
13.
Contemp Nurse ; 30(2): 119-32, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19040379

RESUMO

Children's hospitals are vastly different today from fifty years ago. Although there have been dramatic changes in treatment and environment, the biggest contrast for patients is the involvement of parents and family in the nursing and care of the children. This change is largely due to the work of two men from Great Britain, Dr John Bowlby and James Robertson, whose research findings changed the way children were nursed to include consideration of their psychological alongside physical needs. This caused a revolution in the nursing of children that spread throughout Australasia. Bowlby and Robertson's work is largely forgotten now, but it forms the basis for the current policy of nursing children within the context of the family. This paper includes excerpts from an Australian oral history collection of twenty-six narratives from former child patients, parents and nurses and the personal papers of Dr Bowlby.


Assuntos
Enfermagem Pediátrica/história , Austrália , Criança , História do Século XX , Hospitalização , Humanos , Relações Enfermeiro-Paciente
14.
J Med Chem ; 50(20): 4818-31, 2007 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-17824679

RESUMO

The action of renin is the rate-limiting step of the renin-angiotensin system (RAS), a key regulator of blood pressure. Effective renin inhibitors directly block the RAS entirely at source and, thus, may provide a vital weapon for hypertension therapy. Our efforts toward identifying novel small-molecule peptidomimetic renin inhibitors have resulted in the design of transition-state isosteres such as 1 bearing an all-carbon 8-phenyl-octanecarboxamide framework. Optimization of the extended P3 portion of 1 and extensive P2' modifications provided analogues with improved in vitro potencies in the presence of plasma. X-ray resolution of rh-renin/38a in the course of SAR work surprisingly unveiled the exploitation of a previously unexplored pocket (S3sp) important for strong binding affinities. Several inhibitors demonstrated oral efficacy in sodium-depleted marmosets. The most potent, 38a, induced dose-dependently a pronounced reduction in mean arterial blood pressure, paralleled by complete blockade of active plasma renin, up to 8 h post-dose. Oral bioavailability of 38a was 16% in marmosets.


Assuntos
Amidas/síntese química , Anisóis/síntese química , Anti-Hipertensivos/síntese química , Caprilatos/síntese química , Peptídeos/química , Renina/antagonistas & inibidores , Administração Oral , Amidas/química , Amidas/farmacologia , Animais , Anisóis/química , Anisóis/farmacologia , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Disponibilidade Biológica , Pressão Sanguínea/efeitos dos fármacos , Callithrix , Caprilatos/química , Caprilatos/farmacologia , Cristalografia por Raios X , Frequência Cardíaca/efeitos dos fármacos , Humanos , Cinética , Modelos Moleculares , Mimetismo Molecular , Estrutura Molecular , Ligação Proteica , Renina/sangue , Estereoisomerismo , Relação Estrutura-Atividade
15.
J Med Chem ; 50(20): 4832-44, 2007 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-17824680

RESUMO

Due to its function in the rate limiting initial step of the renin-angiotensin system, renin is a particularly promising target for drugs designed to control hypertension, a growing risk to health worldwide. Despite vast efforts over more than two decades, no orally efficacious renin inhibitor had reached the market. As a result of a structure-based topological design approach, we have identified a novel class of small-molecule inhibitors with good oral blood-pressure lowering effects in primates. Further lead optimization aimed for improvement of in vivo potency and duration of action, mainly by P2' modifications at the hydroxyethylene transition-state isostere. These efforts resulted in the discovery of aliskiren (46, CGP060536B, SPP100), a highly potent, selective inhibitor of renin, demonstrating excellent efficacy in sodium-depleted marmosets after oral administration, with sustained duration of action in reducing dose-dependently mean arterial blood pressure. Aliskiren has recently received regulatory approval by the U.S. Food and Drug Administration for the treatment of hypertension.


Assuntos
Amidas/síntese química , Anti-Hipertensivos/síntese química , Caprilatos/síntese química , Fumaratos/síntese química , Renina/antagonistas & inibidores , Administração Oral , Amidas/química , Amidas/farmacologia , Animais , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Callithrix , Caprilatos/química , Caprilatos/farmacologia , Cristalografia por Raios X , Fumaratos/química , Fumaratos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Cinética , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Renina/sangue , Estereoisomerismo , Relação Estrutura-Atividade
16.
Cancer Chemother Pharmacol ; 57(6): 761-71, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16172907

RESUMO

PTK/ZK is a novel, oral angiogenesis inhibitor that specifically targets all 3 vascular endothelial growth factor (VEGF) receptor tyrosine kinases and is currently in phase III clinical trials. In early clinical trials, PTK/ZK demonstrated a dose-dependent reduction in tumor vascular parameters as measured by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and an acute increase in plasma VEGF levels. The reduction in tumor vascularity was significantly correlated with improved clinical outcome in patients with advanced colorectal cancer and liver metastases. To assess the predictive value of a mouse model of tumor metastases, comparisons were performed for the biological activity of PTK/ZK in the mouse model and in patients with liver metastases in the clinical phase I trials. An orthotopic, syngeneic mouse model was used: C57BL/6 mice injected in the ear with murine B16/BL6 melanoma cells which metastases to the cervical lymph-nodes. The primary tumor and spontaneous metastases express VEGF and VEGF receptors and respond to treatment with VEGFR tyrosine kinase inhibitors. PTK/ZK was administered orally, with assessments by DCE-MRI of the metastases and plasma VEGF taken predose and at 3 days posttreatment and efficacy determined at 7 days posttreatment. Dose-ranging studies in naive mice provided preclinical pharmacokinetic data, while two dose-escalation phase I studies provided clinical pharmacokinetic data. An exposure-response relationship was observed both for mouse metastases (measured as % tumor weight treated/control) and for human liver metastases (measured as % regression). In the B16/BL6 model, the active dose of 50 mg/kg PTK/ZK yielded 62.4 (+/- 16.0) h microM plasma exposure, which is comparable to the plasma area under the concentration time curve (AUC) achieved by the 1000 mg dose of PTK/ZK used in clinical trials. At this exposure level in clinical trials, DCE-MRI showed a reduction in the area under the enhancement curve (IAUC) to 47% of baseline. At a similar exposure in the PTK/ZK-treated mice, a reduction in IAUC to 75% of baseline was observed. Furthermore, at doses of 50 mg/kg PTK/ZK and above, an increase in plasma VEGF level 10 h after drug administration was observed in mice which was consistent with findings from the clinical trials. In conclusion, the preclinical pharmacodynamics of PTK/ZK correlate well with clinical activity in phase I trials over comparable exposures to the drug. Thus, data from this preclinical model proved to be consistent with and thus predictive of the biologic effects of PTK/ZK in phase I/II clinical trials.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Melanoma Experimental/tratamento farmacológico , Ftalazinas/uso terapêutico , Piridinas/uso terapêutico , Receptores de Fatores de Crescimento do Endotélio Vascular/sangue , Inibidores da Angiogênese/sangue , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/uso terapêutico , Animais , Biomarcadores , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Cães , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Imageamento por Ressonância Magnética , Melanoma Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ftalazinas/sangue , Ftalazinas/farmacocinética , Inibidores de Proteínas Quinases/sangue , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/sangue , Piridinas/farmacocinética , Ratos , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
17.
Circ Res ; 94(8): 1124-32, 2004 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15044320

RESUMO

Although vascular endothelial growth factor (VEGF) has been described as a potent angiogenic stimulus, its application in therapy remains difficult: blood vessels formed by exposure to VEGF tend to be malformed and leaky. In nature, the principal form of VEGF possesses a binding site for ECM components that maintain it in the immobilized state until released by local cellular enzymatic activity. In this study, we present an engineered variant form of VEGF, alpha2PI1-8-VEGF121, that mimics this concept of matrix-binding and cell-mediated release by local cell-associated enzymatic activity, working in the surgically-relevant biological matrix fibrin. We show that matrix-conjugated alpha2PI1-8-VEGF121 is protected from clearance, contrary to native VEGF121 mixed into fibrin, which was completely released as a passive diffusive burst. Grafting studies on the embryonic chicken chorioallantoic membrane (CAM) and in adult mice were performed to assess and compare the quantity and quality of neovasculature induced in response to fibrin implants formulated with matrix-bound alpha2PI1-8-VEGF121 or native diffusible VEGF121. Our CAM measurements demonstrated that cell-demanded release of alpha2PI1-8-VEGF121 increases the formation of new arterial and venous branches, whereas exposure to passively released wild-type VEGF121 primarily induced chaotic changes within the capillary plexus. Specifically, our analyses at several levels, from endothelial cell morphology and endothelial interactions with periendothelial cells, to vessel branching and network organization, revealed that alpha2PI1-8-VEGF121 induces vessel formation more potently than native VEGF121 and that those vessels possess more normal morphologies at the light microscopic and ultrastructural level. Permeability studies in mice validated that vessels induced by alpha2PI1-8-VEGF121 do not leak. In conclusion, cell-demanded release of engineered VEGF121 from fibrin implants may present a therapeutically safe and practical modality to induce local angiogenesis.


Assuntos
Fibrina/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Alantoide/irrigação sanguínea , Alantoide/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Sítios de Ligação , Permeabilidade Capilar/efeitos dos fármacos , Embrião de Galinha , Córion/irrigação sanguínea , Córion/efeitos dos fármacos , Difusão , Implantes de Medicamento , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/ultraestrutura , Endotélio Vascular/citologia , Proteínas da Matriz Extracelular/análise , Fibrina/administração & dosagem , Géis , Humanos , Camundongos , Morfogênese/efeitos dos fármacos , Cadeias Pesadas de Miosina , Miosina não Muscular Tipo IIB , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Engenharia de Proteínas , Estrutura Terciária de Proteína , Receptor TIE-2/análise , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise , alfa 2-Antiplasmina/química , alfa 2-Antiplasmina/genética
18.
Clin Cancer Res ; 11(21): 7773-84, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16278399

RESUMO

PURPOSE: Evaluation of vascular disruptive activity in orthotopic models as potential surrogate biomarkers of tumor response to the microtubule-stabilizing agent patupilone. EXPERIMENTAL DESIGN: Mice bearing metastatic B16/BL6 melanoma and rats bearing mammary BN472 tumors received vehicle or efficacious patupilone doses (4 and 0.8-1.5 mg/kg i.v., respectively). Tumor vascularity assessment by dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and interstitial fluid pressure (IFP) occurred at baseline, 2 days (mice and rats), and 6 days (rats) after treatment and were compared with histologic measurements and correlated with tumor response. RESULTS: In B16/BL6 metastases, patupilone (4 mg/kg) induced a 21 +/- 5% decrease (P < 0.001) in tumor blood volume and a 32 +/- 15% decrease (P = 0.02) in IFP after 2 days and reduced tumor growth and vessel density (>42%) after 2 weeks (P < or = 0.014). Patupilone dose-dependently inhibited BN472 tumor growth (day 6) and reduced IFP on days 2 and 6 (-21% to -70%), and the percentage change in IFP correlated (P < 0.01) with the change in tumor volume. In both models, histology and vascular casts confirmed decreases in tumor blood volume. One patupilone (0.8 mg/kg) administration decreased (P < 0.01) tumor IFP (54 +/- 4%), tumor blood volume (50 +/- 6%), and vessel diameter (40 +/- 11%) by day 6 but not the apparent diffusion coefficient, whereas histology showed that apoptosis was increased 2.4-fold and necrosis was unchanged. Apoptosis correlated negatively (P < 0.001) with IFP, tumor blood volume, and tumor volume, whereas tumor blood volume and IFP were correlated positively (P = 0.0005). CONCLUSIONS: Vascular disruptive effects of patupilone were detected in situ using dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and IFP. Changes in IFP preceded and correlated with tumor response, suggesting that IFP may be a surrogate biomarker for patupilone efficacy.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Epotilonas/farmacologia , Neovascularização Patológica , Animais , Apoptose , Vasos Sanguíneos/patologia , Caspase 3 , Caspases/metabolismo , Meios de Contraste/farmacologia , Modelos Animais de Doenças , Endotélio Vascular/patologia , Feminino , Imuno-Histoquímica , Metástase Linfática , Imageamento por Ressonância Magnética/métodos , Melanoma/patologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Pressão , Ratos , Fatores de Tempo
19.
Clin Cancer Res ; 11(12): 4521-32, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15958638

RESUMO

PURPOSE: Receptor tyrosine kinases of the ErbB family play important roles in the control of tumor growth. Vascular endothelial growth factor (VEGF) stimulates endothelial cell proliferation, enhances vascular permeability, and plays an important role in tumor vascularization. We evaluated the effects of selective VEGF receptor (VEGFR; PTK787/ZK222584) and ErbB (PKI166 and ZD1839) inhibitors on tumor growth and angiogenesis and asked whether additional therapeutic benefit was conferred by combination treatment. EXPERIMENTAL DESIGN: The antitumor activity of each inhibitor alone or in combination was assessed in human cancer models in immunocompromised mice. ErbB receptor expression and activation of downstream signaling pathway was evaluated in both tumor and endothelial cells. RESULTS: Both ErbB inhibitors significantly enhanced the antitumor activity of PTK787/ZK222584. In vitro, ErbB1 inhibition blocked VEGF release by tumor cells and proliferation of both tumor and endothelial cells. In an in vitro angiogenesis assay, epidermal growth factor (EGF) stimulated the release of VEGF by smooth muscle cells resulting in increased angiogenesis, a response blocked by administration of PTK787/ZK222584. Under basal condition, both ZD1839 and PTK787/ZK222584 blocked sprouting, likely via inhibition of an autocrine ErbB1 loop and VEGFR signaling, respectively, in endothelial cells. In conditions of limiting VEGF, EGF plays an important role in endothelial cell proliferation, survival, and sprouting. CONCLUSION: We have shown that activation of ErbB1 triggers a plethora of effects, including direct effects on tumor and endothelial cells and indirect effects mediated via induction of VEGF release. Simultaneous blockade of ErbB1 and VEGFR pathways results in a cooperative antitumor effect, indicating that this combination may represent a valid therapeutic strategy.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Receptores ErbB/antagonistas & inibidores , Ftalazinas/farmacologia , Piridinas/farmacologia , Quinazolinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Técnicas de Cocultura , Sinergismo Farmacológico , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Imunofluorescência , Gefitinibe , Humanos , Immunoblotting , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Experimentais/prevenção & controle , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Inibidores de Proteínas Quinases/farmacologia , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Cancer Res ; 62(14): 4015-22, 2002 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12124335

RESUMO

Antiangiogenic therapy is a promising new strategy of inhibiting tumor growthand formation of metastases. Recently, a number of compounds with different effects on tumor endothelial cells have entered clinical trials and revealed the need for diagnostic methods to detect their biological activity. Dynamic enhanced magnetic resonance imaging (dyMRI) is used in most clinical trials with antiangiogenic active compounds. We evaluated this method by using PTK787/ZK 222584, a specific inhibitor of the VEGF-receptor tyrosine kinases, which showed antitumoral and antiangiogenic activity in a murine renal cell carcinoma (RENCA) model. After intrarenal application of RENCA cells, mice developed a primary tumor and metastases to the lung and abdominal lymph nodes. After daily oral therapy for 21 days with either PTK787/ZK 222584 at a dose of 50 mg/kg or vehicle, primary tumors of all animals were analyzed by dyMRI. Gadolinium-DOTA (Dotarem) was used as a contrast agent to detect vessel permeability and contrast agent extravasation, whereas intravascular iron oxide nanoparticles (Endorem) were used to detect partial tumor blood volume. Additionally, vessel density, architecture, diameter, and blood flow velocity were investigated by appropriate methods. Surprisingly, no changes in extravasation occurred under treatment with PTK787/ZK 222584 as compared with the control group, whereas a significant decrease in vessel permeability occurred. Furthermore, an increase in partial blood volume was found in the PTK787/ZK 222584-treated group, although vessel density was reduced as seen by histology. Using the corrosion cast technique, reduction in vessel density was significant but not very pronounced and predominantly attributable to the loss of microvessels only. This finding correlated with a shift to large vessel diameters in the primary tumors of PTK787/ZK 222584-treated animals and with reduction of blood flow velocity in the tumor feeding renal artery. From these findings, we conclude that the treatment with PTK787/ZK 222584 primarily reduces the number of tumor microvessels, accompanied by a hemodynamic dilation of the remaining vessels. This dilation could influence the result of dyMRI such that no change in extravasation or even an increase in partial tumor blood volume could be observed.


Assuntos
Inibidores da Angiogênese/farmacologia , Carcinoma de Células Renais/irrigação sanguínea , Inibidores Enzimáticos/farmacologia , Neoplasias Renais/irrigação sanguínea , Ftalazinas/farmacologia , Piridinas , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores de Fatores de Crescimento/antagonistas & inibidores , Animais , Benzimidazóis/metabolismo , Vasos Sanguíneos/anatomia & histologia , Vasos Sanguíneos/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Carcinoma de Células Renais/tratamento farmacológico , Extravasamento de Materiais Terapêuticos e Diagnósticos , Feminino , Corantes Fluorescentes/metabolismo , Compostos Heterocíclicos/sangue , Neoplasias Renais/tratamento farmacológico , Angiografia por Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/tratamento farmacológico , Compostos Organometálicos/sangue , Receptores de Fatores de Crescimento do Endotélio Vascular , Fluxo Sanguíneo Regional/efeitos dos fármacos
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