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1.
bioRxiv ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38328141

RESUMO

Lysine-specific demethylase 1 (LSD1 or KDM1A ) has emerged as a critical mediator of tumor progression in metastatic castration-resistant prostate cancer (mCRPC). Among mCRPC subtypes, neuroendocrine prostate cancer (NEPC) is an exceptionally aggressive variant driven by lineage plasticity, an adaptive resistance mechanism to androgen receptor axis-targeted therapies. Our study shows that LSD1 expression is elevated in NEPC and associated with unfavorable clinical outcomes. Using genetic approaches, we validated the on-target effects of LSD1 inhibition across various models. We investigated the therapeutic potential of bomedemstat, an orally bioavailable, irreversible LSD1 inhibitor with low nanomolar potency. Our findings demonstrate potent antitumor activity against CRPC models, including tumor regressions in NEPC patient-derived xenografts. Mechanistically, our study uncovers that LSD1 inhibition suppresses the neuronal transcriptional program by downregulating ASCL1 through disrupting LSD1:INSM1 interactions and de-repressing YAP1 silencing. Our data support the clinical development of LSD1 inhibitors for treating CRPC - especially the aggressive NE phenotype. Statement of Significance: Neuroendocrine prostate cancer presents a clinical challenge due to the lack of effective treatments. Our research demonstrates that bomedemstat, a potent and selective LSD1 inhibitor, effectively combats neuroendocrine prostate cancer by downregulating the ASCL1- dependent NE transcriptional program and re-expressing YAP1.

2.
Appl Opt ; 62(17): 4699-4705, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707168

RESUMO

We analyze here a candidate system for correcting the wander of a self-channeled laser pulse using a fast-steering mirror along with a cooperative beacon imaged with a telescope. For our model system, the imaging telescope is coaxial with the propagation of the outgoing pulse. In the ideal case, any incoming light gathered from the beacon would be collimated, such that taking a centroid beacon image would yield the precise tip and tilt required for the self-channeled pulse to propagate back to the beacon on the reciprocal path. The degree to which reality differs from this ideal case determines the effectiveness of the wander correction. We simulate our system for a range of propagation and imaging conditions. We also show that in the absence of image noise (i.e., when the beacon power is arbitrarily high, and the signal-to-noise ratio is not an important consideration), the system exhibits its best performance when the receiving aperture diameter of the imaging system is close to the transverse size of the outgoing pulse, maximizing reciprocity. When realistic noise and finite beacon power are included in the simulation, however, we find that this reciprocity advantage may not be sufficient to compensate for the reduced photon count and resolving power of a small receiving aperture. In this case, the optimal aperture diameter will be the smallest possible, which allows for an acceptable signal-to-noise ratio.

3.
Opt Express ; 30(13): 22306-22320, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36224931

RESUMO

We investigate the interpulse thermal interaction of a train of ultrashort laser pulses and develop a model to describe the isobaric heating of air by a train of pulses undergoing filamentation. We calculate the heating of air from a single laser pulse and the resulting refractive index perturbation encountered by subsequent pulses, and use this to simulate the propagation of a high-power pulse train. The simulations show deflection of laser filaments by the thermal refractive index consistent with previous experimental measurements.

4.
Trials ; 22(1): 433, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229728

RESUMO

BACKGROUND: Adaptive model-based dose-finding designs have demonstrated advantages over traditional rule-based designs but have increased statistical complexity but uptake has been slow especially outside of cancer trials. TRAFIC is a multi-centre, early phase trial in rheumatoid arthritis incorporating a model-based design. METHODS: A Bayesian adaptive dose-finding phase I trial rolling into a single-arm, single-stage phase II trial. Model parameters for phase I were chosen via Monte Carlo simulation evaluating objective performance measures under clinically relevant scenarios and incorporated stopping rules for early termination. Potential designs were further calibrated utilising dose transition pathways. DISCUSSION: TRAFIC is an MRC-funded trial of a re-purposed treatment demonstrating that it is possible to design, fund and implement a model-based phase I trial in a non-cancer population within conventional research funding tracks and regulatory constraints. The phase I design allows borrowing of information from previous trials, all accumulated data to be utilised in decision-making, verification of operating characteristics through simulation, improved understanding for management and oversight teams through dose transition pathways. The rolling phase II design brings efficiencies in trial conduct including site and monitoring activities and cost. TRAFIC is the first funded model-based dose-finding trial in inflammatory disease demonstrating that small phase I/II trials can have an underlying statistical basis for decision-making and interpretation. TRIAL REGISTRATION: Trials Registration: ISRCTN, ISRCTN36667085 . Registered on September 26, 2014.


Assuntos
Artrite Reumatoide , Neoplasias , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Teorema de Bayes , Simulação por Computador , Relação Dose-Resposta a Droga , Humanos , Projetos de Pesquisa
5.
Phys Rev Lett ; 125(13): 133201, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034483

RESUMO

Nonlinear self-guided propagation of intense long-wave infrared (LWIR) laser pulses is of significant recent interest, as it promises high power transmission without beam breakup and multifilamentation. Central to self-guiding is the mechanism for the arrest of self-focusing collapse. Here, we show that discrete avalanche sites centered on submicron aerosols can arrest self-focusing, providing a new mechanism for self-guided propagation of moderate intensity LWIR pulses in outdoor environments. Our conclusions are supported by simulations of LWIR pulse propagation using an effective index approach that incorporates the time-resolved plasma dynamics of discrete avalanche breakdown sites.

6.
Ann R Coll Surg Engl ; 101(8): e164-e168, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31537109

RESUMO

Neuro-Behçet's disease (NBD) is a serious manifestation of Behçet's disease (BD) and can affect either the central or peripheral nervous systems, or both. It occurs in 10-50% of patients with BD. We report on a patient with an unusual intraparenchymal lesion, initially thought to be a brain tumour. Histological examination revealed vasculitis consistent with BD. Clinicians should include NBD as a differential diagnosis when considering an isolated inflammatory intracranial lesion.


Assuntos
Síndrome de Behçet/diagnóstico , Granuloma de Células Plasmáticas/diagnóstico , Adulto , Síndrome de Behçet/complicações , Síndrome de Behçet/patologia , Biópsia , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Diagnóstico Diferencial , Granuloma de Células Plasmáticas/etiologia , Granuloma de Células Plasmáticas/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino
7.
Bone Joint J ; 101-B(2): 124-131, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30700118

RESUMO

Nerve transfer has become a common and often effective reconstructive strategy for proximal and complex peripheral nerve injuries of the upper limb. This case-based discussion explores the principles and potential benefits of nerve transfer surgery and offers in-depth discussion of several established and valuable techniques including: motor transfer for elbow flexion after musculocutaneous nerve injury, deltoid reanimation for axillary nerve palsy, intrinsic re-innervation following proximal ulnar nerve repair, and critical sensory recovery despite non-reconstructable median nerve lesions.


Assuntos
Transferência de Nervo/métodos , Traumatismos dos Nervos Periféricos/cirurgia , Extremidade Superior/inervação , Adulto , Axila/inervação , Feminino , Humanos , Masculino , Nervo Mediano/lesões , Nervo Mediano/cirurgia , Pessoa de Meia-Idade , Nervo Musculocutâneo/anatomia & histologia , Nervo Musculocutâneo/lesões , Nervo Musculocutâneo/cirurgia , Traumatismos dos Nervos Periféricos/diagnóstico , Traumatismos dos Nervos Periféricos/etiologia , Nervos Periféricos/anatomia & histologia , Nervos Periféricos/cirurgia , Luxação do Ombro/etiologia , Nervo Ulnar/lesões , Nervo Ulnar/transplante , Extremidade Superior/lesões , Adulto Jovem
8.
West Indian med. j ; 67(spe): 493-497, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-1045871

RESUMO

ABSTRACT Introduction: The Bahamas became a member state of the International Atomic Energy Agency (IAEA) on January 7, 2014 (1). The purpose of this paper is to inform the reader on The Bahamas' ability to provide services that utilize radiation. Method: A study was conducted on various clinics across The Bahamas, New Providence in particular (primary sample area), Grand Bahama, Abaco and Exuma. Twenty per cent of the staff members of the respective locations were given questionnaires and the chief personnel were interviewed. Staff members were advised that their responses would remain anonymous and were welcomed to participate, thereafter. Microsoft Excel was used for data input and processing. Original surveys were checked against the dataset for potential errors. Results: Thirty-one clinics were approached to participate in the survey, of which 25 participated resulting in an 81% response rate. Fifty questionnaires were completed in total. Two clinics had multiple locations; therefore, 27 clinics (23 private, 4 public) participated in total. The included map illustrates the sample area of the survey, with New Providence being the primary sample area. The number of modalities, patients treated and frequency of quality assurance checks were also evaluated. Conclusion: Most of the examined clinics outsourced technicians and physicists to perform quality checks. This suggests that there is a need for qualified local technical support. Further studies are needed to understand the full extent of the country's needs regarding medical radiation and figuring out the steps necessary for approaching this subject.


RESUMEN Introducción: Las Bahamas se convirtieron en un Estado Miembro de la Agencia Internacional de Energía Atómica (AIEA) el 7 de enero de 2014 (1). El propósito de este trabajo es informar al lector sobre la capacidad de las Bahamas para prestar servicios que utilizan radiación. Método: Se realizó un estudio en varias clínicas a través de las Bahamas, Nueva Providencia en particular (área de muestra primaria), Gran Bahama, Abaco y Exuma. El veinte por ciento de los miembros del personal de las respectivas locaciones recibieron cuestionarios y el personal dirigente fueron entrevistados. A los miembros del personal se les informó que sus respuestas permanecerían anónimas, y se les dio la bienvenida por su participación. Para la entrada y el procesamiento de datos se usó Microsoft Excel. Las encuestas originales se chequearon contra el conjunto de datos para a fin de detectar posibles errores. Resultados: Treinta y una clínicas fueron abordadas para participar en la encuesta, de las cuales 25 participaron, para una tasa de respuesta de 81%. En total se completaron 50 cuestionarios. Dos clínicas tenían múltiples localidades. Por lo tanto, 27 clínicas (23 privadas, 4 públicas) participaron en total. El mapa incluido ilustra el área de la muestra de la encuesta, en la que Nueva Providencia es el área de la muestra primaria. El número de modalidades, los pacientes tratados, y la frecuencia de los controles de garantía de calidad, también fueron evaluados. Conclusión: La mayor parte de las clínicas examinadas subcontrataron técnicos y físicos para realizar chequeos de la calidad. Esto sugiere que hay necesidad de apoyo técnico local calificado. Se necesitan estudios adicionales para entender el alcance completo de las necesidades del país en relación con la radiación médica y los pasos necesarios para abordar este asunto.


Assuntos
Humanos , Radioterapia/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde , Necessidades e Demandas de Serviços de Saúde , Jamaica
10.
Clin Exp Immunol ; 187(1): 113-123, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27667787

RESUMO

Tolerogenic dendritic cells (tolDC) are a new immunotherapeutic tool for the treatment of rheumatoid arthritis (RA) and other autoimmune disorders. We have established a method to generate stable tolDC by pharmacological modulation of human monocyte-derived DC. These tolDC exert potent pro-tolerogenic actions on CD4+ T cells. Lack of interleukin (IL)-12p70 production is a key immunoregulatory attribute of tolDC but does not explain their action fully. Here we show that tolDC express transforming growth factor (TGF)-ß1 at both mRNA and protein levels, and that expression of this immunoregulatory cytokine is significantly higher in tolDC than in mature monocyte-derived DC. By inhibiting TGF-ß1 signalling we demonstrate that tolDC regulate CD4+ T cell responses in a manner that is at least partly dependent upon this cytokine. Crucially, we also show that while there is no significant difference in expression of TGF-ßRII on CD4+ T cells from RA patients and healthy controls, RA patient CD4+ T cells are measurably less responsive to TGF-ß1 than healthy control CD4+ T cells [reduced TGF-ß-induced mothers against decapentaplegic homologue (Smad)2/3 phosphorylation, forkhead box protein 3 (FoxP3) expression and suppression of (IFN)-γ secretion]. However, CD4+ T cells from RA patients can, nonetheless, be regulated efficiently by tolDC in a TGF-ß1-dependent manner. This work is important for the design and development of future studies investigating the potential use of tolDC as a novel immunotherapy for the treatment of RA.


Assuntos
Artrite Reumatoide/terapia , Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica , Imunoterapia/métodos , Fator de Crescimento Transformador beta1/metabolismo , Artrite Reumatoide/imunologia , Células Cultivadas , Colecalciferol/farmacologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/transplante , Dexametasona/farmacologia , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imunomodulação , Interleucina-12/genética , Interleucina-12/metabolismo , Ativação Linfocitária , Proteína Smad2/metabolismo
11.
Rev Sci Instrum ; 87(7): 073107, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27475548

RESUMO

We present a pair of optimized objective lenses with long working distances of 117 mm and 65 mm, respectively, that offer diffraction limited performance for both Cs and Rb wavelengths when imaging through standard vacuum windows. The designs utilise standard catalog lens elements to provide a simple and cost-effective solution. Objective 1 provides NA = 0.175 offering 3 µm resolution whilst objective 2 is optimized for high collection efficiency with NA = 0.29 and 1.8 µm resolution. This flexible design can be further extended for use at shorter wavelengths by simply re-optimising the lens separations.

12.
J Intern Med ; 279(1): 41-59, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26403380

RESUMO

The introduction of targeted biological therapies has revolutionised the management of immune-mediated inflammatory diseases (IMIDs) such as rheumatoid arthritis, ankylosing spondylitis, psoriasis and inflammatory bowel disease. Following treatment with these therapies, many patients experience significant improvements in different aspects of their disease, including symptoms, work productivity and other outcomes relevant for individuals and society. However, due to the complexity of biological drug development and manufacturing processes, the costs of these therapies are relatively high. Indeed, the financial burden on healthcare systems due to biological therapies is considerable and lack of patient access to effective treatment remains a concern in many parts of the world. As many reference biological therapies have now reached or are near to patent expiry, a number of 'biosimilar' drugs have been developed for use in various clinical settings, and some of these drugs are already in use in several countries. While the potential pharmacoeconomic benefits of cost-effective biosimilars seem clear, several issues have been raised regarding, for example, the definition of biosimilarity and the validity of indication extrapolation, as well as the 'switchability' and relative immunogenicity of biosimilars and their reference drugs. In this review, these issues will be discussed with reference to CT-P13, a biosimilar of the anti-tumour necrosis factor monoclonal antibody infliximab, which is approved in Europe and elsewhere for the treatment of various IMIDs. Other important issues, including those related to data collection during nonclinical and clinical development of biosimilars, are also discussed.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Medicamentos Biossimilares/uso terapêutico , Doenças do Sistema Imunitário/terapia , Fator de Necrose Tumoral alfa/imunologia , Humanos , Inflamação/terapia , Infliximab/uso terapêutico
13.
Ann Rheum Dis ; 75(5): 899-907, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25923217

RESUMO

OBJECTIVE: A population of synovial inflammatory dendritic cells (infDCs) has recently been identified in rheumatoid arthritis (RA) and is thought to be monocyte-derived. Here, we investigated the role and source of granulocyte macrophage-colony-stimulating factor (GM-CSF) in the differentiation of synovial infDC in RA. METHODS: Production of GM-CSF by peripheral blood (PB) and synovial fluid (SF) CD4+ T cells was assessed by ELISA and flow cytometry. In vitro CD4+ T-cell polarisation experiments were performed with T-cell activating CD2/CD3/CD28-coated beads in the absence or presence of pro-Th1 or pro-Th17 cytokines. CD1c+ DC and CD16+ macrophage subsets were flow-sorted and analysed morphologically and functionally (T-cell stimulatory/polarising capacity). RESULTS: RA-SF CD4+ T cells produced abundant GM-CSF upon stimulation and significantly more than RA-SF mononuclear cells depleted of CD4+ T cells. GM-CSF-producing T cells were significantly increased in RA-SF compared with non-RA inflammatory arthritis SF, active RA PB and healthy donor PB. GM-CSF-producing CD4+ T cells were expanded by Th1-promoting but not Th17-promoting conditions. Following coculture with RA-SF CD4+ T cells, but not healthy donor PB CD4+ T cells, a subpopulation of monocytes differentiated into CD1c+ infDC; a process dependent on GM-CSF. These infDC displayed potent alloproliferative capacity and enhanced GM-CSF, interleukin-17 and interferon-γ production by CD4+ T cells. InfDC with an identical phenotype to in vitro generated cells were significantly enriched in RA-SF compared with non-RA-SF/tissue/PB. CONCLUSIONS: We demonstrate a therapeutically tractable feedback loop of GM-CSF secreted by RA synovial CD4+ T cells promoting the differentiation of infDC with potent capacity to induce GM-CSF-producing CD4+ T cells.


Assuntos
Artrite Reumatoide/imunologia , Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Antígenos CD1/análise , Técnicas de Cocultura , Citocinas/biossíntese , Glicoproteínas/análise , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Humanos , Imunofenotipagem , Receptores de Lipopolissacarídeos/análise , Macrófagos/imunologia , Monócitos/imunologia , Osteoartrite/imunologia , Líquido Sinovial/imunologia , Células Th1/imunologia
14.
Prostate ; 74(4): 395-407, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24338924

RESUMO

BACKGROUND: The tumor microenvironment (TME) plays an essential role in supporting and promoting tumor growth and progression. An inflammatory stroma is a widespread hallmark of the prostate TME, and prostate tumors are known to co-evolve with their reactive stroma. Cancer-associated fibroblasts (CAFs) within the reactive stroma play a salient role in secreting cytokines that contribute to this inflammatory TME. Although a number of inflammatory mediators have been identified, a clear understanding of key factors initiating the formation of reactive stroma is lacking. METHODS: We explored whether tumor secreted extracellular Hsp90 alpha (eHsp90α) may initiate a reactive stroma. Prostate stromal fibroblasts (PrSFs) were exposed to exogenous Hsp90α protein, or to conditioned medium (CM) from eHsp90α-expressing prostate cancer cells, and evaluated for signaling, motility, and expression of prototypic reactive markers. In tandem, ELISA assays were utilized to characterize Hsp90α-mediated secreted factors. RESULTS: We report that exposure of PrSFs to eHsp90 upregulates the transcription and protein secretion of IL-6 and IL-8, key inflammatory cytokines known to play a causative role in prostate cancer progression. Cytokine secretion was regulated in part via a MEK/ERK and NF-κB dependent pathway. Secreted eHsp90α also promoted the rapid and durable activation of the oncogenic inflammatory mediator signal transducer and activator of transcription (STAT3). Finally, eHsp90 induced the expression of MMP-3, a well-known mediator of fibrosis and the myofibroblast phenotype. CONCLUSIONS: Our results provide compelling support for eHsp90α as a transducer of signaling events culminating in an inflammatory and reactive stroma, thereby conferring properties associated with prostate cancer progression.


Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , NF-kappa B/metabolismo , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Células Estromais/metabolismo , Microambiente Tumoral/fisiologia , Movimento Celular , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP90/genética , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Masculino , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , NF-kappa B/genética , Próstata/patologia , Neoplasias da Próstata/patologia , Transdução de Sinais , Células Estromais/patologia
15.
Pharmacogenomics J ; 14(2): 171-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23856853

RESUMO

Eligibility for anti-tumour necrosis factor (TNF) therapy in most European countries is restricted to severe, active rheumatoid arthritis (RA). The DAS28 score is a marker of disease severity and incorporates one of two inflammatory markers, erythrocyte sedimentation rate (ESR) or C-reactive protein. We aimed to determine the relation between genetic variants known to affect ESR and levels of ESR in patients with active RA. DNA samples were genotyped for four single-nucleotide polymorphisms (SNPs) rs7527798 (CR1L), rs6691117 (CR1), rs10903129 (TMEM57) and rs1043879 (C1orf63). The association between SNPs and baseline ESR, baseline DAS28-ESR, and change in DAS28-ESR was evaluated. Baseline ESR was significantly associated with CR1 rs6691117 genotype (P=0.01). No correlation was identified between baseline DAS28-ESR or change in DAS28-ESR. In conclusion, genetic variation in the gene encoding CR1 may alter ESR levels but not DAS28-ESR, indicating no adjustment for CR1 genotype is required in the assessment of patients with severe active RA.


Assuntos
Artrite Reumatoide/genética , Sedimentação Sanguínea , Receptores de Complemento 3b/genética , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Proteína C-Reativa/genética , Europa (Continente) , Feminino , Genômica , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento
16.
Clin Exp Immunol ; 172(2): 148-57, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23574312

RESUMO

Dendritic cells with tolerogenic function (tolDC) have become a promising immunotherapeutic tool for reinstating immune tolerance in rheumatoid arthritis (RA) and other autoimmune diseases. The concept underpinning tolDC therapy is that it specifically targets the pathogenic autoimmune response while leaving protective immunity intact. Findings from human in-vitro and mouse in-vivo studies have been translated into the development of clinical grade tolDC for the treatment of autoimmune disorders. Recently, two tolDC trials in RA and type I diabetes have been carried out and other trials are in progress or are imminent. In this review, we provide an update on tolDC therapy, in particular in relation to the treatment of RA, and discuss the challenges and the future perspectives of this new experimental immunotherapy.


Assuntos
Transferência Adotiva , Artrite Reumatoide/terapia , Células Dendríticas/transplante , Diabetes Mellitus Tipo 1/terapia , Artrite Reumatoide/imunologia , Autoimunidade , Células Dendríticas/imunologia , Diabetes Mellitus Tipo 1/imunologia , Humanos , Tolerância Imunológica , Imunoterapia
17.
Ann Rheum Dis ; 71(2): 180-5, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21917822

RESUMO

OBJECTIVES: Osteopontin is an extracellular matrix protein with diverse immunomodulatory functions. The authors assessed the safety, tolerability, pharmacokinetics, pharmacodynamics and initial efficacy of the humanised monoclonal antibody ASK8007, which blocks osteopontin. METHODS: In this double-blind, multicentre, combined first-in-man, single-dose escalation (phase I, part A) and proof-of-concept, multiple-dose (phase IIA, part B) study, rheumatoid arthritis (RA) patients with active disease were randomly assigned to receive ASK8007 or placebo intravenously. Safety monitoring, pharmacokinetic and pharmacodynamic analyses and clinical assessments were performed throughout the study. The expression of phenotypic cell markers was evaluated in synovial tissue biopsy samples obtained at baseline and 43 days after initiation of treatment (part B) by immunohistochemistry and digital image analysis. Two co-primary efficacy endpoints were the change from baseline in the disease activity score evaluated in 28 joints (DAS28) and the change from baseline in the number of CD68 synovial sublining macrophages, both assessed on day 43 (part B). RESULTS: ASK8007 was overall safe and well tolerated up to the highest studied dose (20 mg/kg). Quantifiable concentrations of ASK8007 were detected in synovial fluid. No differences were observed for changes from baseline in DAS28 and CD68 sublining macrophages between ASK8007 and placebo-treated patients. Within the ASK8007 treatment group, there were also no apparent clinical responses or changes in sublining macrophages. In addition, ASK8007 treatment did not change other assessed biomarkers. CONCLUSIONS: Osteopontin blockade is well tolerated and not related to safety concerns. These results consistently show that osteopontin blockade is unlikely to induce robust clinical improvement in RA patients.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Osteopontina/antagonistas & inibidores , Adulto , Idoso , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antirreumáticos/farmacocinética , Antirreumáticos/uso terapêutico , Artrite Reumatoide/metabolismo , Biomarcadores/metabolismo , Sedimentação Sanguínea , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Meia-Vida , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Osteopontina/sangue , Índice de Gravidade de Doença , Membrana Sinovial/imunologia , Resultado do Tratamento
18.
J Oncol ; 2010: 412985, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20628489

RESUMO

Tumor vascularization is an essential modulator of early tumor growth, progression, and therapeutic outcome. Although antiangiogenic treatments appear promising, intrinsic and acquired tumor resistance contributes to treatment failure. Clinical inhibition of the molecular chaperone heat shock protein 90 (Hsp90) provides an opportunity to target multiple aspects of this signaling resiliency, which may elicit more robust and enduring tumor repression relative to effects elicited by specifically targeted agents. This review highlights several primary effectors of angiogenesis modulated by Hsp90 and describes the clinical challenges posed by the redundant circuitry of these pathways. The four main topics addressed include (1) Hsp90-mediated regulation of HIF/VEGF signaling, (2) chaperone-dependent regulation of HIF-independent VEGF-mediated angiogenesis, (3) Hsp90-dependent targeting of key proangiogenic receptor tyrosine kinases and modulation of drug resistance, and (4) consideration of factors such as tumor microenvironment that pose several challenges for the clinical efficacy of anti-angiogenic therapy and Hsp90-targeted strategies.

20.
Ann Rheum Dis ; 69(9): 1629-35, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20488885

RESUMO

OBJECTIVES: This phase III study evaluated the efficacy and safety of rituximab plus methotrexate (MTX) in patients with active rheumatoid arthritis (RA) who had an inadequate response to MTX and who were naïve to prior biological treatment. METHODS: Patients with active disease on stable MTX (10-25 mg/week) were randomised to rituximab 2 x 500 mg (n=168), rituximab 2 x 1000 mg (n=172), or placebo (n=172). From week 24, patients not in remission (Disease Activity Score (28 joints) > or =2.6) received a second course of rituximab; patients initially assigned to placebo switched to rituximab 2 x 500 mg. The primary end point was American College of Rheumatology 20 (ACR20) response at week 24. All patients were followed until week 48. RESULTS: At week 24, both doses of rituximab showed statistically superior efficacy (p<0.0001) to placebo (ACR20: 54%, 51% and 23%; rituximab (2 x 500 mg) + MTX, rituximab (2 x 1000 mg) + MTX and placebo + MTX, respectively). Secondary end points were also significantly improved for both rituximab groups compared with placebo. Further improvements in both rituximab arms were observed from week 24 to week 48. Rituximab + MTX was well tolerated, demonstrating comparable safety to placebo + MTX through to week 24, and between rituximab doses through to week 48. CONCLUSIONS: Rituximab (at 2 x 500 mg and 2 x 1000 mg) plus MTX significantly improved clinical outcomes at week 24, which were further improved by week 48. No significant differences in either clinical or safety outcomes were apparent between the rituximab doses.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antirreumáticos/administração & dosagem , Artrite Reumatoide/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Murinos , Antirreumáticos/efeitos adversos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/imunologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Metotrexato/efeitos adversos , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Rituximab , Índice de Gravidade de Doença , Resultado do Tratamento
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