RESUMO
Oncogenic forms of the kinase FLT3 are important therapeutic targets in acute myeloid leukemia (AML); however, clinical responses to small-molecule kinase inhibitors are short-lived as a result of the rapid emergence of resistance due to point mutations or compensatory increases in FLT3 expression. We sought to develop a complementary pharmacological approach whereby proteasome-mediated FLT3 degradation could be promoted by inhibitors of the deubiquitinating enzymes (DUBs) responsible for cleaving ubiquitin from FLT3. Because the relevant DUBs for FLT3 are not known, we assembled a focused library of most reported small-molecule DUB inhibitors and carried out a cellular phenotypic screen to identify compounds that could induce the degradation of oncogenic FLT3. Subsequent target deconvolution efforts allowed us to identify USP10 as the critical DUB required to stabilize FLT3. Targeting of USP10 showed efficacy in preclinical models of mutant-FLT3 AML, including cell lines, primary patient specimens and mouse models of oncogenic-FLT3-driven leukemia.
Assuntos
Antineoplásicos/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Tiofenos/farmacologia , Ubiquitina Tiolesterase/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/metabolismo , Animais , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos NOD , Estrutura Molecular , Mutação , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Inibidores de Proteínas Quinases/química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Tiofenos/química , Células Tumorais Cultivadas , Ubiquitina/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Tirosina Quinase 3 Semelhante a fms/genéticaRESUMO
Virtual simulation technology is the next step in using simulation as an accepted teaching-learning pedagogy in nursing. The purpose of this multisite, quasi-experimental, three-group, posttest-only design was to evaluate the effectiveness and participant satisfaction of vSim for Nursing in an Adult Health Nursing course. Although the quantitative findings (examination scores and postsimulation scores) were not statistically significant, participants overwhelmingly found vSim for Nursing to be a positive experiential learning endeavor. Ninety-one percent of the participants (n = 61) indicated that vSim for Nursing helped them understand adult health concepts and that vSim for Nursing was beneficial to learning. vSim for Nursing warrants further investigation, using other methods to measure effectiveness to ascertain whether knowledge acquisition is indeed improved as indicated by participant data in this study.
Assuntos
Currículo , Bacharelado em Enfermagem/métodos , Treinamento por Simulação , Interface Usuário-Computador , Adolescente , Adulto , Feminino , Humanos , Aprendizagem , Masculino , Pesquisa em Educação em Enfermagem , Pesquisa em Avaliação de Enfermagem , Pesquisa Metodológica em Enfermagem , Projetos Piloto , Estudantes de Enfermagem/psicologia , Estudantes de Enfermagem/estatística & dados numéricos , Adulto JovemRESUMO
PURPOSE: Genetic counselors (GCs) increasingly play key roles in advancing genomic medicine through innovative research. Here, we examine one large cohort of GCs' evolving contributions to the literature, with the goal of facilitating worldwide professional development for GCs through scholarly activities. METHODS: Publications were cataloged by members of the Section of Genetic Counseling (Section), established at the Children's Hospital of Philadelphia and the University of Pennsylvania in 2014, including publication year, journal, impact factor, and author position. Data were organized using the "My Bibliography" tool on the National Center for Biotechnology Information website and a Research Electronic Data Capture database created to initially collect manuscripts published through 30 June 2020. A subsequent survey captured publications through 5 February 2024. RESULTS: An amount of 52 of 120 (43%) GCs shared their curriculum vitae/papers. 992 unique publications were identified from 1986 to 2024. Since 2013, no less than 32 papers were published annually by Section members and no less than 10 GCs contributed to publications yearly. Impact factors typically averaged >5.0 per year. Areas of foci diversified considerably since 2015. CONCLUSIONS: Here, we establish that GCs indeed contribute to scholarly work as evidenced by the number of publications alone. The establishment of an academic home may have contributed, given publications increased concurrent to launching the Section, providing a model for organizing GCs at institutions nationally and internationally. Highlighting such achievements will foster the expansion of GC roles in the era of precision genomic medicine and therapy. Considering ways to support GCs towards expanding these activities is equally important.
Assuntos
Aconselhamento Genético , Humanos , Conselheiros , Fator de Impacto de RevistasRESUMO
The Bcr-Abl tyrosine kinase oncogene causes chronic myelogenous leukemia (CML) and Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). We describe a novel selective inhibitor of Bcr-Abl, AMN107 (IC50 <30 nM), which is significantly more potent than imatinib, and active against a number of imatinib-resistant Bcr-Abl mutants. Crystallographic analysis of Abl-AMN107 complexes provides a structural explanation for the differential activity of AMN107 and imatinib against imatinib-resistant Bcr-Abl. Consistent with its in vitro and pharmacokinetic profile, AMN107 prolonged survival of mice injected with Bcr-Abl-transformed hematopoietic cell lines or primary marrow cells, and prolonged survival in imatinib-resistant CML mouse models. AMN107 is a promising new inhibitor for the therapy of CML and Ph+ ALL.
Assuntos
Antineoplásicos/farmacologia , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Pirimidinas/química , Pirimidinas/farmacologia , Animais , Benzamidas , Células da Medula Óssea/citologia , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Células-Tronco Hematopoéticas/citologia , Mesilato de Imatinib , Concentração Inibidora 50 , Camundongos , Modelos Biológicos , Modelos Químicos , Mutação , Mycoplasma/metabolismo , Fosforilação , Piperazinas/farmacologia , Retroviridae/genética , Fatores de TempoRESUMO
Multiple receptor tyrosine kinases (RTKs), including PDGFR, have been validated as therapeutic targets in glioblastoma multiforme (GBM), yet inhibitors of RTKs have had limited clinical success. As various antiapoptotic mechanisms render GBM cells resistant to chemo- and radiotherapy, we hypothesized that these antiapoptotic mechanisms also confer resistance to RTK inhibition. We found that in vitro inhibition of PDGFR in human GBM cells initiated the intrinsic pathway of apoptosis, as evidenced by mitochondrial outer membrane permeabilization, but downstream caspase activation was blocked by inhibitor of apoptosis proteins (IAPs). Consistent with this, inhibition of PDGFR combined with small molecule inactivation of IAPs induced apoptosis in human GBM cells in vitro and had synergistic antitumor effects in orthotopic mouse models of GBM and in primary human GBM neurospheres. These results demonstrate that concomitant inhibition of IAPs can overcome resistance to RTK inhibitors in human malignant GBM cells, and suggest that blockade of IAPs has the potential to improve treatment outcomes in patients with GBM.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Animais , Benzamidas , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Mesilato de Imatinib , Camundongos , Modelos Biológicos , Neurônios/metabolismo , Oligopeptídeos/administração & dosagem , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagemRESUMO
Leukemias that harbor translocations involving the mixed lineage leukemia gene (MLL) possess unique biologic characteristics and often have an unfavorable prognosis. Gene expression analyses demonstrate a distinct profile for MLL-rearranged leukemias with consistent high-level expression of select Homeobox genes, including HOXA9. Here, we investigated the effects of HOXA9 suppression in MLL-rearranged and MLL-germline leukemias using RNA interference. Gene expression profiling after HOXA9 suppression demonstrated co-down-regulation of a program highly expressed in human MLL-AML and murine MLL-leukemia stem cells, including HOXA10, MEIS1, PBX3, and MEF2C. We demonstrate that HOXA9 depletion in 17 human AML/ALL cell lines (7 MLL-rearranged, 10 MLL-germline) induces proliferation arrest and apoptosis specifically in MLL-rearranged cells (P = .007). Similarly, assessment of primary AMLs demonstrated that HOXA9 suppression induces apoptosis to a greater extent in MLL-rearranged samples (P = .01). Moreover, mice transplanted with HOXA9-depleted t(4;11) SEMK2 cells revealed a significantly lower leukemia burden, thus identifying a role for HOXA9 in leukemia survival in vivo. Our data indicate an important role for HOXA9 in human MLL-rearranged leukemias and suggest that targeting HOXA9 or downstream programs may be a novel therapeutic option.
Assuntos
Proteínas de Homeodomínio/fisiologia , Leucemia Mieloide Aguda/mortalidade , Proteína de Leucina Linfoide-Mieloide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Animais , Células Cultivadas , Proteínas de Ligação a DNA/genética , Histona-Lisina N-Metiltransferase , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Mutação/fisiologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , RNA Interferente Pequeno/farmacologia , Análise de Sobrevida , Fatores de Elongação da Transcrição , Estudos de Validação como AssuntoRESUMO
The interaction of multiple myeloma (MM) cells with their microenvironment in the bone marrow (BM) provides a protective environment and resistance to therapeutic agents. We hypothesized that disruption of the interaction of MM cells with their BM milieu would lead to their sensitization to therapeutic agents such as bortezomib, melphalan, doxorubicin, and dexamethasone. We report that the CXCR4 inhibitor AMD3100 induces disruption of the interaction of MM cells with the BM reflected by mobilization of MM cells into the circulation in vivo, with kinetics that differed from that of hematopoietic stem cells. AMD3100 enhanced sensitivity of MM cell to multiple therapeutic agents in vitro by disrupting adhesion of MM cells to bone marrow stromal cells (BMSCs). Moreover, AMD3100 increased mobilization of MM cells to the circulation in vivo, increased the ratio of apoptotic circulating MM cells, and enhanced the tumor reduction induced by bortezomib. Mechanistically, AMD3100 significantly inhibited Akt phosphorylation and enhanced poly(ADP-ribose) polymerase (PARP) cleavage as a result of bortezomib, in the presence of BMSCs in coculture. These experiments provide a proof of concept for the use of agents that disrupt interaction with the microenvironment for enhancement of efficacy of cytotoxic agents in cancer therapy.
Assuntos
Fármacos Anti-HIV/farmacologia , Antineoplásicos/farmacologia , Medula Óssea/metabolismo , Compostos Heterocíclicos/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Receptores CXCR4/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Benzilaminas , Ácidos Borônicos/farmacologia , Bortezomib , Adesão Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Ensaio de Unidades Formadoras de Colônias , Ciclamos , Resistencia a Medicamentos Antineoplásicos , Fibronectinas/metabolismo , Citometria de Fluxo , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Integrina alfa4beta1/genética , Integrina alfa4beta1/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Lentivirus/genética , Masculino , Camundongos , Camundongos SCID , Pirazinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Células Estromais/metabolismo , Transfecção , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The discovery of new small molecules and their testing in rational combination poses an ongoing problem for rare diseases, in particular, for pediatric cancers such as neuroblastoma. Despite maximal cytotoxic therapy with double autologous stem cell transplantation, outcome remains poor for children with high-stage disease. Because differentiation is aberrant in this malignancy, compounds that modulate transcription, such as histone deacetylase (HDAC) inhibitors, are of particular interest. However, as single agents, HDAC inhibitors have had limited efficacy. In the present study, we use an HDAC inhibitor as an enhancer to screen a small-molecule library for compounds inducing neuroblastoma maturation. To quantify differentiation, we use an enabling gene expression-based screening strategy. The top hit identified in the screen was all-trans-retinoic acid. Secondary assays confirmed greater neuroblastoma differentiation with the combination of an HDAC inhibitor and a retinoid versus either alone. Furthermore, effects of combination therapy were synergistic with respect to inhibition of cellular viability and induction of apoptosis. In a xenograft model of neuroblastoma, animals treated with combination therapy had the longest survival. This work suggests that testing of an HDAC inhibitor and retinoid in combination is warranted for children with neuroblastoma and demonstrates the success of a signature-based screening approach to prioritize compound combinations for testing in rare diseases.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Diferenciação Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores de Histona Desacetilases , Neuroblastoma/tratamento farmacológico , Retinoides/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Perfilação da Expressão Gênica , Humanos , Neuroblastoma/patologia , Retinoides/uso terapêutico , Bibliotecas de Moléculas Pequenas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
An attractive target for therapeutic intervention is constitutively activated, mutant FLT3, which is expressed in a subpopulation of patients with acute myelocyic leukemia (AML) and is generally a poor prognostic indicator in patients under the age of 65 years. PKC412 is one of several mutant FLT3 inhibitors that is undergoing clinical testing, and which is currently in late-stage clinical trials. However, the discovery of drug-resistant leukemic blast cells in PKC412-treated patients with AML has prompted the search for novel, structurally diverse FLT3 inhibitors that could be alternatively used to override drug resistance. Here, we report the potent and selective antiproliferative effects of the novel mutant FLT3 inhibitor NVP-AST487 on primary patient cells and cell lines expressing FLT3-ITD or FLT3 kinase domain point mutants. NVP-AST487, which selectively targets mutant FLT3 protein kinase activity, is also shown to override PKC412 resistance in vitro, and has significant antileukemic activity in an in vivo model of FLT3-ITD(+) leukemia. Finally, the combination of NVP-AST487 with standard chemotherapeutic agents leads to enhanced inhibition of proliferation of mutant FLT3-expressing cells. Thus, we present a novel class of FLT3 inhibitors that displays high selectivity and potency toward FLT3 as a molecular target, and which could potentially be used to override drug resistance in AML.
Assuntos
Antineoplásicos/farmacologia , Carbanilidas/farmacologia , Resistencia a Medicamentos Antineoplásicos , Inibidores de Proteínas Quinases/farmacologia , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular , Leucemia Mieloide Aguda/tratamento farmacológico , Camundongos , Proteínas Mutantes/antagonistas & inibidores , Proteína Quinase C/antagonistas & inibidores , Estaurosporina/análogos & derivadosRESUMO
OBJECTIVES: The aim of the present study was to perform an assessment for secondary traumatic stress (STS), vicarious trauma (VT) and workplace burnout for Australian mental health professionals involved in clinical practice. METHODS: Recruited directly by mail, randomly selected participants were invited to submit a questionnaire by post or online. Of the 480 participants contacted, 152 mental health professionals completed the questionnaire, which contained measures of STS, VT and burnout. RESULTS: Exposure to patients' traumatic material did not affect STS, VT or burnout, contradicting the theory of the originators of STS and VT. Rather, it was found that work-related stressors best predicted therapist distress. CONCLUSIONS: These findings have significant implications for the direction of research and theory development in traumatic stress studies, calling into question the existence of secondary trauma-related phenomena and enterprises aimed at treating the consultants.
Assuntos
Esgotamento Profissional/epidemiologia , Fadiga/epidemiologia , Fadiga/psicologia , Pessoal de Saúde/psicologia , Pessoal de Saúde/estatística & dados numéricos , Transtornos de Estresse Pós-Traumáticos , Adolescente , Adulto , Demografia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Fadiga/diagnóstico , Feminino , Humanos , Relações Interpessoais , Masculino , Prevalência , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/psicologia , Inquéritos e Questionários , Adulto JovemRESUMO
Clinical studies of patients with chronic myeloid leukemia revealed that a common pattern of response is a dramatic fall in the circulating population of blast cells, with a minimal or delayed decrease in marrow blasts, suggesting a protective environment. These observations suggest that a greater understanding of the interaction of stromal cells with leukemic cells is essential. Here, we present an in vivo system for monitoring relative tumor accumulation in leukemic mice and residual disease in leukemic mice treated with a tyrosine kinase inhibitor and an in vitro system for identifying integral factors involved in stromal-mediated cytoprotection. Using the in vivo model, we observed high tumor burden/residual disease in tissues characterized as significant sources of hematopoiesis-promoting stroma, with bone marrow stroma most frequently showing the highest accumulation of leukemia in untreated and nilotinib-treated mice as well as partial protection of leukemic cells from the inhibitory effects of nilotinib. These studies, which showed a pattern of leukemia distribution consistent with what is observed in imatinib- and nilotinib-treated chronic myeloid leukemia patients, were followed by a more in-depth analysis of stroma-leukemia cell interactions that lead to protection of leukemia cells from nilotinib-induced cytotoxicity. For the latter, we used the human BCR-ABL-positive cell line, KU812F, and the human bone marrow stroma cell line, HS-5, to more closely approximate the bone marrow-associated cytoprotection observed in drug-treated leukemia patients. This in vitro system helped to elucidate stromal-secreted viability factors that may play a role in stromal-mediated cytoprotection of tyrosine kinase inhibitor-treated leukemia cells.
Assuntos
Antineoplásicos/toxicidade , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/toxicidade , Animais , Antineoplásicos/uso terapêutico , Células da Medula Óssea/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Camundongos , Camundongos Nus , Inibidores de Proteínas Quinases/metabolismo , Pirimidinas/toxicidade , Células Estromais/fisiologiaRESUMO
Members of the inhibitor of apoptosis protein (IAP) family play a role in mediating apoptosis. Studies suggest that these proteins may be a viable target in leukemia because they have been found to be variably expressed in acute leukemias and are associated with chemosensitivity, chemoresistance, disease progression, remission, and patient survival. Another promising therapeutic target, FLT3, is mutated in about one third of acute myelogenous leukemia (AML) patients; promising results have recently been achieved in clinical trials investigating the effects of the protein tyrosine kinase inhibitor PKC412 on AML patients harboring mutations in the FLT3 protein. Of growing concern, however, is the development of drug resistance resulting from the emergence of point mutations in targeted tyrosine kinases used for treatment of acute leukemia patients. One approach to overriding resistance is to combine structurally unrelated inhibitors and/or inhibitors of different signaling pathways. The proapoptotic IAP inhibitor, LBW242, was shown in proliferation studies done in vitro to enhance the killing of PKC412-sensitive and PKC412-resistant cell lines expressing mutant FLT3 when combined with either PKC412 or standard cytotoxic agents (doxorubicin and Ara-c). In addition, in an in vivo imaging assay using bioluminescence as a measure of tumor burden, a total of 12 male NCr-nude mice were treated for 10 days with p.o. administration of vehicle, LBW242 (50 mg/kg/day), PKC412 (40 mg/kg/day), or a combination of LBW242 and PKC412; the lowest tumor burden was observed in the drug combination group. Finally, the combination of LBW242 and PKC412 was sufficient to override stromal-mediated viability signaling conferring resistance to PKC412.
Assuntos
Antineoplásicos/farmacologia , Materiais Biomiméticos/farmacologia , Proteínas de Transporte , Leucemia/tratamento farmacológico , Proteínas Mitocondriais , Proteínas Mutantes/metabolismo , Oligopeptídeos/farmacologia , Tirosina Quinase 3 Semelhante a fms/metabolismo , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Camundongos , Proteínas Mutantes/genética , Oligopeptídeos/química , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia , Células Estromais/efeitos dos fármacos , Tirosina Quinase 3 Semelhante a fms/genéticaRESUMO
BACKGROUND: The presence of tumor-specific mutations in the cancer genome represents a potential opportunity for pharmacologic intervention to therapeutic benefit. Unfortunately, many classes of oncoproteins (e.g., transcription factors) are not amenable to conventional small-molecule screening. Despite the identification of tumor-specific somatic mutations, most cancer therapy still utilizes nonspecific, cytotoxic drugs. One illustrative example is the treatment of Ewing sarcoma. Although the EWS/FLI oncoprotein, present in the vast majority of Ewing tumors, was characterized over ten years ago, it has never been exploited as a target of therapy. Previously, this target has been intractable to modulation with traditional small-molecule library screening approaches. Here we describe a gene expression-based approach to identify compounds that induce a signature of EWS/FLI attenuation. We hypothesize that screening small-molecule libraries highly enriched for FDA-approved drugs will provide a more rapid path to clinical application. METHODS AND FINDINGS: A gene expression signature for the EWS/FLI off state was determined with microarray expression profiling of Ewing sarcoma cell lines with EWS/FLI-directed RNA interference. A small-molecule library enriched for FDA-approved drugs was screened with a high-throughput, ligation-mediated amplification assay with a fluorescent, bead-based detection. Screening identified cytosine arabinoside (ARA-C) as a modulator of EWS/FLI. ARA-C reduced EWS/FLI protein abundance and accordingly diminished cell viability and transformation and abrogated tumor growth in a xenograft model. Given the poor outcomes of many patients with Ewing sarcoma and the well-established ARA-C safety profile, clinical trials testing ARA-C are warranted. CONCLUSIONS: We demonstrate that a gene expression-based approach to small-molecule library screening can identify, for rapid clinical testing, candidate drugs that modulate previously intractable targets. Furthermore, this is a generic approach that can, in principle, be applied to the identification of modulators of any tumor-associated oncoprotein in the rare pediatric malignancies, but also in the more common adult cancers.
Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Citarabina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Perfilação da Expressão Gênica , Proteínas de Fusão Oncogênica/efeitos dos fármacos , Sarcoma de Ewing/tratamento farmacológico , Fatores de Transcrição/efeitos dos fármacos , Animais , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Citarabina/uso terapêutico , Sistemas de Liberação de Medicamentos , Corantes Fluorescentes/análise , Fluorometria , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Microesferas , Estrutura Molecular , Peso Molecular , Proteínas de Fusão Oncogênica/biossíntese , Proteínas de Fusão Oncogênica/genética , Proteína Proto-Oncogênica c-fli-1 , Interferência de RNA , Proteína EWS de Ligação a RNA , Sarcoma de Ewing/genética , Sarcoma de Ewing/patologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The disease state of cancer appears late in tumor development. Before being diagnosed, a tumor can remain for prolonged periods of time in a dormant state. Dormant human cancer is commonly defined as a microscopic tumor that does not expand in size and remains asymptomatic. Dormant tumors represent an early stage in tumor development and may therefore be a potential target for nontoxic, antiangiogenic therapy that could prevent tumor recurrence. Here, we characterize an experimental model that recapitulates the clinical dormancy of human tumors in mice. We demonstrate that these microscopic dormant cancers switch to the angiogenic phenotype at a predictable time. We further show that while angiogenic liposarcomas expand rapidly after inoculation of tumor cells in mice, nonangiogenic dormant liposarcomas remain microscopic up to one-third of the normal severe combined immune deficiency (SCID) mouse life span, although they contain proliferating tumor cells. Nonangiogenic dormant tumors follow a similar growth pattern in subcutaneous (s.c.) and orthotopic environments. Throughout the dormancy period, development of intratumoral vessels is impaired. In nonangogenic dormant tumors, small clusters of endothelial cells without lumens are observed early after tumor cell inoculation, but the nonangiogenic tumor cannot sustain these vessels, and they disappear within weeks. There is a concomitant decrease in microvessel density, and the nonangiogenic dormant tumor remains harmless to the host. In contrast, microvessel density in tumors increases rapidly after the angiogenic switch and correlates with rapid expansion of tumor mass. Both tumor types cultured in vitro contain fully transformed cells, but only cells from the nonangiogenic human liposarcoma secrete relatively high levels of the angiogenesis inhibitors thrombospondin-1 and TIMP-1. This model suggests that as improved blood or urine molecular biomarkers are developed, the microscopic, nonangiogenic, dormant phase of human cancer may be vulnerable to antiangiogenic therapy years before symptoms, or before anatomical location of a tumor can be detected, by conventional methods.
Assuntos
Lipossarcoma/irrigação sanguínea , Lipossarcoma/patologia , Neovascularização Patológica/fisiopatologia , Animais , Linhagem Celular Tumoral , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Lipossarcoma/metabolismo , Masculino , Camundongos , Camundongos SCID , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Oncogenic FLT3 kinase is a clinically validated target in acute myeloid leukemia (AML), and both multi-targeted and selective FLT3 inhibitors have been developed. Spleen tyrosine kinase (SYK) has been shown to be activated and increased in FLT3-ITD-positive AML patients, and has further been shown to be critical for transformation and maintenance of the leukemic clone in these patients. Further, over-expression of constitutively activated SYK causes resistance to highly selective FLT3 tyrosine kinase inhibitors (TKI). Up to now, the activity of the multi-targeted FLT3 inhibitor, midostaurin, against cells expressing activated SYK has not been explored in the context of leukemia, although SYK has been identified as a target of midostaurin in systemic mastocytosis. We compared the ability of midostaurin to inhibit activated SYK in mutant FLT3-positive AML cells with that of inhibitors displaying dual SYK/FLT3 inhibition, targeted SYK inhibition, and targeted FLT3 inhibition. Our findings suggest that dual FLT3/SYK inhibitors and FLT3-targeted drugs potently kill oncogenic FLT3-transformed cells, while SYK-targeted small molecule inhibition displays minimal activity. However, midostaurin and other dual FLT3/SYK inhibitors display superior anti-proliferative activity when compared to targeted FLT3 inhibitors, such as crenolanib and quizartinib, against cells co-expressing FLT3-ITD and constitutively activated SYK-TEL. Interestingly, additional SYK suppression potentiated the effects of dual FLT3/SYK inhibitors and targeted FLT3 inhibitors against FLT3-ITD-driven leukemia, both in the absence and presence of activated SYK. Taken together, our findings have important implications for the design of drug combination studies in mutant FLT3-positive patients and for the design of future generations of FLT3 inhibitors.
RESUMO
BACKGROUND: In this article, we describe the design and implementation of a comprehensive prostate cancer database developed to collect, store, and access clinical, treatment, and outcomes data for research and clinical care. PATIENTS AND METHODS: The Prostate Cancer Clinical Research Information System is a relational database. Data are entered from multiple sources, including medical records, institutional laboratory, patient registration, pharmacy systems, and clinician forms. The history, design, and operational characteristics of the database are described. Issues regarding necessary staffing and funding of databases are reviewed. RESULTS: Four thousand two hundred forty-six patients have information in the Prostate Cancer Clinical Research Information System. Mean age of patients is 62 years, and 89% are white. Seventy-one percent of patients presented at diagnosis with T1 or T2 disease, and 78% had biopsy Gleason scores of Assuntos
Pesquisa Biomédica
, Bases de Dados Factuais
, Neoplasias da Próstata
, Adulto
, Idoso
, Idoso de 80 Anos ou mais
, Institutos de Câncer
, Humanos
, Masculino
, Pessoa de Meia-Idade
, Neoplasias da Próstata/diagnóstico
, Neoplasias da Próstata/epidemiologia
, Neoplasias da Próstata/terapia
, Resultado do Tratamento
RESUMO
Oligonucleotide arrays that detect single nucleotide polymorphisms were used to generate genome-wide loss of heterozygosity (LOH) maps from laser capture microdissected paraffin-embedded samples using as little as 5 ng of DNA. The allele detection rate from such samples was comparable with that obtained with standard amounts of DNA prepared from frozen tissues. A novel informatics platform, dChipSNP, was used to automate the definition of statistically valid regions of LOH, assign LOH genotypes to prostate cancer samples, and organize by hierarchical clustering prostate cancers based on the pattern of LOH. This organizational strategy revealed apparently distinct genetic subsets of prostate cancer.
Assuntos
Alelos , Biologia Computacional , Perda de Heterozigosidade , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética , DNA de Neoplasias/análise , Humanos , MasculinoRESUMO
HIN-1 (high in normal-1) is a candidate tumor suppressor identified as a gene silenced by methylation in the majority of breast carcinomas. HIN-1 is highly expressed in the mammary gland, trachea, lung, prostate, pancreas, and salivary gland, and in the lung, its expression is primarily restricted to bronchial epithelial cells. In this report, we show that, correlating with the secretory nature of HIN-1, high levels of HIN-1 protein are detected in bronchial lavage, saliva, plasma, and serum. To determine if, similar to breast carcinomas, HIN-1 is also silenced in tumors originating from other organs with high HIN-1 expression, we analyzed its expression and promoter methylation status in lung, prostate, and pancreatic carcinomas. Nearly all prostate and a significant fraction of lung and pancreatic carcinomas showed HIN-1 hypermethylation, and the majority of lung and prostate tumors lacked HIN-1 expression. In lung carcinomas, the degree of HIN-1 methylation differed among tumor subtypes (P = 0.02), with the highest level of HIN-1 methylation observed in squamous cell carcinomas and the lowest in small cell lung cancer. In lung adenocarcinomas, the expression of HIN-1 correlated with cellular differentiation status. Hypermethylation of the HIN-1 promoter was also frequently observed in normal tissue adjacent to tumors but not in normal tissue from noncancer patients, implying that HIN-1 promoter methylation may be a marker of premalignant changes. Thus, silencing of HIN-1 expression and methylation of its promoter occurs in multiple human cancer types, suggesting that elimination of HIN-1 function may contribute to several forms of epithelial tumorigenesis.
Assuntos
Citocinas/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Neoplasias/classificação , Neoplasias/genética , Regiões Promotoras Genéticas/genética , Proteínas Supressoras de Tumor/genética , Líquidos Corporais/metabolismo , Linhagem Celular Tumoral , Citocinas/metabolismo , Humanos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/genética , Masculino , Neoplasias/patologia , Pâncreas/metabolismo , Neoplasias Pancreáticas/genética , Próstata/metabolismo , Neoplasias da Próstata/genética , Proteínas Supressoras de Tumor/metabolismoRESUMO
Routine voluntary HIV testing with the right to decline (the "opt-out" approach) is recommended for all pregnant women in the United States but not all are tested. We examined data from surveys of prenatal care providers to identify factors associated with universal testing among patients. Data are from a probability survey conducted in 1999 with prenatal care providers in four separate areas. Survey participants completed a self-administered questionnaire. We computed the percentage of providers reporting universal testing by characteristics of the provider's practice, medical specialty, how strongly they encouraged testing, perceptions of patients' risk, and whether they saw patients in public clinics. In the four locations (Brooklyn, New York; North Carolina; Connecticut; and Dade County, Florida) 95%-99% of providers reported that they routinely offered HIV testing to all pregnant women; the average percentage tested was 64%-89%. The percentage reporting that all of their patients were tested ranged from 12%-62%. The percent of providers reporting universal testing was positively associated with the degree to which testing was encouraged, particularly encouragement to women perceived to be low risk. In some areas, universal testing varied by medical profession, with obstetric physicians and residents, and nurse-midwives reporting a lower percentage of universal testing than family practice physicians and residents. To achieve the goal of routine HIV testing of all pregnant women, education and training must be delivered to all prenatal care providers. This training should emphasize the importance of routine testing. Even with the opt-out approach, many women may decline testing if their doctor does not recommend and encourage HIV testing.
Assuntos
Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Programas de Rastreamento/organização & administração , Avaliação de Resultados em Cuidados de Saúde , Complicações Infecciosas na Gravidez/diagnóstico , Sorodiagnóstico da AIDS , Intervalos de Confiança , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Recém-Nascido , Programas de Rastreamento/estatística & dados numéricos , Gravidez , Cuidado Pré-Natal/métodos , Avaliação de Programas e Projetos de Saúde , Medição de Risco , Inquéritos e Questionários , Gestão da Qualidade Total , Estados UnidosRESUMO
The application of psychological debriefing has become an expected and widespread intervention following exposure to trauma. This article assesses the wisdom of such an approach and reports upon expert consensus regarding its use. Meta-analytic and narrative reviews are summarised and areas of agreement and disagreement are outlined. In sum, it was concluded that the majority of people do not become traumatised from stressful events; that generic psychological debriefing, when applied to individuals, appears to have little impact on functioning; that a specific form of debriefing called Critical Incident Stress Debriefing holds the possibility of noxious effects for some participants and that those most deleteriously affected by debriefing appear to be those most distressed by the initial trauma; that there is no randomised controlled trial evidence to support the validity of group debriefing approaches; and that early intervention using Cognitive Behavioural techniques for those with clinically significant presentations appears the most promising approach. A generic set of guidelines for intervention following trauma is provided.