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Eukaryotic transcription factors (TFs) activate gene expression by recruiting cofactors to promoters. However, the relationships between TFs, promoters and their associated cofactors remain poorly understood. Here we combine GAL4-transactivation assays with comparative CRISPR-Cas9 screens to identify the cofactors used by nine different TFs and core promoters in human cells. Using this dataset, we associate TFs with cofactors, classify cofactors as ubiquitous or specific and discover transcriptional co-dependencies. Through a reductionistic, comparative approach, we demonstrate that TFs do not display discrete mechanisms of activation. Instead, each TF depends on a unique combination of cofactors, which influences distinct steps in transcription. By contrast, the influence of core promoters appears relatively discrete. Different promoter classes are constrained by either initiation or pause-release, which influences their dynamic range and compatibility with cofactors. Overall, our comparative cofactor screens characterize the interplay between TFs, cofactors and core promoters, identifying general principles by which they influence transcription.
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Regiões Promotoras Genéticas , Fatores de Transcrição , Ativação Transcricional , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sistemas CRISPR-Cas , Transcrição Gênica , Regulação da Expressão GênicaRESUMO
The liver exhibits a remarkable capacity to regenerate following injury. Despite this unique attribute, toxic injury is a leading cause of liver failure. The temporal processes by which the liver senses injury and initiates regeneration remain unclear. Here, we developed a transgenic zebrafish model wherein hepatocyte-specific expression of uracil phosphoribosyltransferase (UPRT) enabled the implementation of SLAM-ITseq to investigate the nascent transcriptome during initiation of liver injury and regeneration. Using this approach, we identified a rapid metabolic transition from the fed to the fasted state that was followed by induction of the nuclear erythroid 2-related factor (Nrf2) antioxidant program. We find that activation of Nrf2 in hepatocytes is required to induce the pentose phosphate pathway (PPP) and improve survival following liver injury. Mechanistically, we demonstrate that inhibition of the PPP disrupts nucleotide biosynthesis to prevent liver regeneration. Together, these studies provide fundamental insights into the mechanism by which early metabolic adaptation to injury facilitates tissue regeneration.
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Regeneração Hepática , Via de Pentose Fosfato , Animais , Via de Pentose Fosfato/genética , Regeneração Hepática/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Fígado/metabolismoRESUMO
Therapies that enhance antitumor immunity have altered the natural history of many cancers. Consequently, leveraging nonoverlapping mechanisms to increase immunogenicity of cancer cells remains a priority. Using a novel enzymatic inhibitor of the RNA methyl-transferase METTL3, we demonstrate a global decrease in N6-methyladenosine (m6A) results in double-stranded RNA (dsRNA) formation and a profound cell-intrinsic interferon response. Through unbiased CRISPR screens, we establish dsRNA-sensing and interferon signaling are primary mediators that potentiate T-cell killing of cancer cells following METTL3 inhibition. We show in a range of immunocompetent mouse models that although METTL3 inhibition is equally efficacious to anti-PD-1 therapy, the combination has far greater preclinical activity. Using SPLINTR barcoding, we demonstrate that anti-PD-1 therapy and METTL3 inhibition target distinct malignant clones, and the combination of these therapies overcomes clones insensitive to the single agents. These data provide the mole-cular and preclinical rationale for employing METTL3 inhibitors to promote antitumor immunity in the clinic. SIGNIFICANCE: This work demonstrates that METTL3 inhibition stimulates a cell-intrinsic interferon response through dsRNA formation. This immunomodulatory mechanism is distinct from current immunotherapeutic agents and provides the molecular rationale for combination with anti-PD-1 immune-checkpoint blockade to augment antitumor immunity. This article is featured in Selected Articles from This Issue, p. 2109.
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Interferons , Metiltransferases , Animais , Camundongos , Interferons/genética , Metiltransferases/genética , Metiltransferases/metabolismo , RNA de Cadeia DuplaRESUMO
Patients with estrogen receptor (ER)-positive breast cancer are at risk of metastatic relapse for decades after primary tumor resection and treatment, a consequence of dormant disseminated tumor cells (DTCs) reawakening at secondary sites. Here we use syngeneic ER+ mouse models in which DTCs display a dormant phenotype in young mice but accelerated metastatic outgrowth in an aged or fibrotic microenvironment. In young mice, low-level Pdgfc expression by ER+ DTCs is required for their maintenance in secondary sites but is insufficient to support development of macrometastases. By contrast, the platelet-derived growth factor (PDGF)-Chi environment of aging or fibrotic lungs promotes DTC proliferation and upregulates tumor cell Pdgfc expression stimulating further stromal activation, events that can be blocked by pharmacological inhibition of PDGFRα or with a PDGF-C-blocking antibody. These results highlight the role of the changing microenvironment in regulating DTC outgrowth and the opportunity to target PDGF-C signaling to limit metastatic relapse in ER+ breast cancer.
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Neoplasias da Mama , Fator de Crescimento Derivado de Plaquetas , Microambiente Tumoral , Animais , Camundongos , Linfocinas/genética , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Recidiva , Microambiente Tumoral/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologiaRESUMO
Precise control of activating H3K4me3 and repressive H3K27me3 histone modifications at bivalent promoters is essential for normal development and frequently corrupted in cancer. By coupling a cell surface readout of bivalent MHC class I gene expression with whole-genome CRISPR-Cas9 screens, we identify specific roles for MTF2-PRC2.1, PCGF1-PRC1.1 and Menin-KMT2A/B complexes in maintaining bivalency. Genetic loss or pharmacological inhibition of Menin unexpectedly phenocopies the effects of polycomb disruption, resulting in derepression of bivalent genes in both cancer cells and pluripotent stem cells. While Menin and KMT2A/B contribute to H3K4me3 at active genes, a separate Menin-independent function of KMT2A/B maintains H3K4me3 and opposes polycomb-mediated repression at bivalent genes. Release of KMT2A from active genes following Menin targeting alters the balance of polycomb and KMT2A at bivalent genes, facilitating gene activation. This functional partitioning of Menin-KMT2A/B complex components reveals therapeutic opportunities that can be leveraged through inhibition of Menin.
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Células-Tronco Pluripotentes , Fatores de Transcrição , Proteínas do Grupo Polycomb/genética , Fatores de Transcrição/genética , Genoma , Regiões Promotoras GenéticasRESUMO
There is increasing recognition of the prognostic significance of tumor cell major histocompatibility complex (MHC) class II expression in anti-cancer immunity. Relapse of acute myeloid leukemia (AML) following allogeneic stem cell transplantation (alloSCT) has recently been linked to MHC class II silencing in leukemic blasts; however, the regulation of MHC class II expression remains incompletely understood. Utilizing unbiased CRISPR-Cas9 screens, we identify that the C-terminal binding protein (CtBP) complex transcriptionally represses MHC class II pathway genes, while the E3 ubiquitin ligase complex component FBXO11 mediates degradation of CIITA, the principal transcription factor regulating MHC class II expression. Targeting these repressive mechanisms selectively induces MHC class II upregulation across a range of AML cell lines. Functionally, MHC class II+ leukemic blasts stimulate antigen-dependent CD4+ T cell activation and potent anti-tumor immune responses, providing fundamental insights into the graft-versus-leukemia effect. These findings establish the rationale for therapeutic strategies aimed at restoring tumor-specific MHC class II expression to salvage AML relapse post-alloSCT and also potentially to enhance immunotherapy outcomes in non-myeloid malignancies.
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Proteínas F-Box , Leucemia Mieloide Aguda , Oxirredutases do Álcool , Proteínas de Ligação a DNA , Proteínas F-Box/genética , Antígenos HLA/genética , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Ativação Linfocitária , Proteína-Arginina N-Metiltransferases/metabolismo , Recidiva , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Mutations and loss of E-cadherin protein expression define the vast majority of invasive lobular carcinomas. In a subset of these cases, the heterogeneous expression of E-cadherin is observed either as wild-type (strong membranous) expression or aberrant expression (cytoplasmic expression). However, it is unclear as to whether the two components would be driven by distinct genetic or epigenetic alterations. Here, we used whole genome DNA sequencing and methylation array profiling of two separately dissected components of nine invasive lobular carcinomas with heterogeneous E-cadherin expression. E-cadherin negative and aberrant/positive components of E-cadherin heterogeneous tumours showed a similar mutational, copy number and promoter methylation repertoire, suggesting they arise from a common ancestor, as opposed to the collision of two independent tumours. We found that the majority of E-cadherin heterogeneous tumours harboured CDH1 mutations in both the E-cadherin negative and aberrant/positive components together with somatic mutations in additional driver genes known to be enriched in both pure invasive carcinomas of no special type and invasive lobular breast cancers, whereas these were less commonly observed in CDH1 wild-type tumours. CDH1 mutant tumours also exhibited a higher mutation burden as well as increased presence of APOBEC-dependent mutational signatures 2 and 13 compared to CDH1 wild-type tumours. Together, our results suggest that regardless of E-cadherin protein expression, tumours showing heterogeneous expression of E-cadherin should be considered as part of the spectrum of invasive lobular breast cancers.
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Genome-wide association studies coupled with large-scale replication and fine-scale mapping studies have identified more than 150 genomic regions that are associated with breast cancer risk. Here, we review efforts to translate these findings into a greater understanding of disease mechanism. Our review comes in the context of a recently published fine-scale mapping analysis of these regions, which reported 352 independent signals and a total of 13,367 credible causal variants. The vast majority of credible causal variants map to noncoding DNA, implicating regulation of gene expression as the mechanism by which functional variants influence risk. Accordingly, we review methods for defining candidate-regulatory sequences, methods for identifying putative target genes and methods for linking candidate-regulatory sequences to putative target genes. We provide a summary of available data resources and identify gaps in these resources. We conclude that while much work has been done, there is still much to do. There are, however, grounds for optimism; combining statistical data from fine-scale mapping with functional data that are more representative of the normal "at risk" breast, generated using new technologies, should lead to a greater understanding of the mechanisms that influence an individual woman's risk of breast cancer.
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Neoplasias da Mama , Estudo de Associação Genômica Ampla , Neoplasias da Mama/genética , Feminino , Predisposição Genética para Doença , Genômica , Humanos , Polimorfismo de Nucleotídeo ÚnicoRESUMO
A combination of genetic and functional approaches has identified three independent breast cancer risk loci at 2q35. A recent fine-scale mapping analysis to refine these associations resulted in 1 (signal 1), 5 (signal 2), and 42 (signal 3) credible causal variants at these loci. We used publicly available in silico DNase I and ChIP-seq data with in vitro reporter gene and CRISPR assays to annotate signals 2 and 3. We identified putative regulatory elements that enhanced cell-type-specific transcription from the IGFBP5 promoter at both signals (30- to 40-fold increased expression by the putative regulatory element at signal 2, 2- to 3-fold by the putative regulatory element at signal 3). We further identified one of the five credible causal variants at signal 2, a 1.4 kb deletion (esv3594306), as the likely causal variant; the deletion allele of this variant was associated with an average additional increase in IGFBP5 expression of 1.3-fold (MCF-7) and 2.2-fold (T-47D). We propose a model in which the deletion allele of esv3594306 juxtaposes two transcription factor binding regions (annotated by estrogen receptor alpha ChIP-seq peaks) to generate a single extended regulatory element. This regulatory element increases cell-type-specific expression of the tumor suppressor gene IGFBP5 and, thereby, reduces risk of estrogen receptor-positive breast cancer (odds ratio = 0.77, 95% CI 0.74-0.81, p = 3.1 × 10-31).
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Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Anotação de Sequência Molecular , Regiões Promotoras Genéticas , Neoplasias da Mama/genética , Sistemas CRISPR-Cas , Linhagem Celular , Mapeamento Cromossômico , Cromossomos Humanos Par 2 , Feminino , Estudos de Associação Genética , Variação Genética , Humanos , Fatores de Risco , Deleção de SequênciaRESUMO
Red Blood Cells (RBCs) have been increasingly recognized to play important roles in hemostasis and the mechanisms by which they do so continue to be elucidated. First and foremost, RBC biomechanics are the principal determinant of viscosity and flow dynamics of blood, which strongly influence all features of hemostasis. Of note, morphologic pathology, such as that found in sickle cell disease, leads to increased risk of thrombotic disease. RBC surface interactions govern signaling between platelets and RBCs and also aid in the conversion of prothrombin to thrombin. Additionally, RBCs generate microparticles which have been shown to reduce clotting time. Finally, blood clot structure and maturation are dependent on the inclusion of RBCs in forming thrombi. Here, we review the above mechanisms of RBC contribution to hemostasis.
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The ability to identify regulatory interactions that mediate gene expression changes through distal elements, such as risk loci, is transforming our understanding of how genomes are spatially organized and regulated. Capture Hi-C (CHi-C) is a powerful tool to delineate such regulatory interactions. However, primary analysis and downstream interpretation of CHi-C profiles remains challenging and relies on disparate tools with ad-hoc input/output formats and specific assumptions for statistical modeling. Here we present a data processing and interaction calling toolkit (CHiCANE), specialized for the analysis and meaningful interpretation of CHi-C assays. In this protocol, we demonstrate applications of CHiCANE to region capture Hi-C (rCHi-C) and promoter capture Hi-C (pCHi-C) libraries, followed by quality assessment of interaction peaks, as well as downstream analysis specific to rCHi-C and pCHi-C to aid functional interpretation. For a typical rCHi-C/pCHi-C dataset this protocol takes up to 3 d for users with a moderate understanding of R programming and statistical concepts, although this is dependent on dataset size and compute power available. CHiCANE is freely available at https://cran.r-project.org/web/packages/chicane .
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Genômica/métodos , Sequências Reguladoras de Ácido Nucleico/genética , Elementos Facilitadores Genéticos/genética , Epigenoma , Genoma , Código das Histonas , Modelos Genéticos , Anotação de Sequência Molecular , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas , Locos de Características Quantitativas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estatística como AssuntoRESUMO
AIMS AND OBJECTIVES: To investigate the impact and sustainability of the Care Maker programme across England from the perspective of those involved in its delivery. BACKGROUND: The Care Maker programme was launched in England in 2013. It aims to support the "Compassion in Practice" strategy, with particular emphasis on the 6Cs of care, compassion, competence, communication, courage and commitment. Care Makers were recruited in an ambassadorial role. The intention was to inspire individuals throughout the National Health Service in England to bridge national policy with those delivering care. DESIGN: A mixed methods design was chosen, but this article focuses on two of the four distinct empirical data collection phases undertaken as part of this evaluation: a questionnaire with Care Makers; and two case studies of separate National Health Service trust sites. METHOD: Data were collected for this evaluation in 2015. An online questionnaire was distributed to the total population of Care Makers across the National Health Service in England. It included a combination of open and closed questions. The case studies involved semistructured telephone interviews with a range of professionals engaged with the Care Maker programme across the trust sites. RESULTS: Care Makers reported that participation in the programme had offered opportunities in terms of improving the quality-of-care provision in the workplace as well as contributing towards their own professional development. CONCLUSION: The Care Maker programme has supported and helped underpin the nursing, midwifery and care strategy "Compassion in Practice". RELEVANCE TO CLINICAL PRACTICE: This model of using volunteers to embed strategy and policy could potentially be used in other areas of clinical practice and indeed in other countries.
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Enfermagem/normas , Assistência Centrada no Paciente/normas , Avaliação de Programas e Projetos de Saúde , Adulto , Empatia , Inglaterra , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Medicina EstatalRESUMO
Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants with cytotoxic, teratogenic and carcinogenic properties. Bioremediation studies with bacteria have led to the identification of dioxygenases (DOXs) in the first step to degrade these recalcitrant compounds. In this study, we characterized the role of the Arabidopsis thaliana AT5G05600, a putative DOX of the flavonol synthase family, in the transformation of PAHs. Phenotypic analysis of loss-of-function mutant lines showed that these plant lines were less sensitive to the toxic effects of phenanthrene, suggesting possible roles of this gene in PAH degradation in vivo. Interestingly, these mutant lines showed less accumulation of H2O2 after PAH exposure. Transgenic lines over-expressing At5g05600 showed a hypersensitive response and more oxidative stress after phenanthrene treatments. Moreover, fluorescence spectra results of biochemical assays with the recombinant His-tagged protein AT5G05600 detected chemical modifications of phenanthrene. Taken together, these results support the hypothesis that AT5G05600 is involved in the catabolism of PAHs and the accumulation of toxic intermediates during PAH biotransformation in plants. This research represents the first step in the design of transgenic plants with the potential to degrade PAHs, leading to the development of vigorous plant varieties that can reduce the levels of these pollutants in the environment.
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Arabidopsis/enzimologia , Oxirredutases/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Biodegradação Ambiental , Peróxido de Hidrogênio , Mutação , Fenantrenos/análise , Fenantrenos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes do Solo/toxicidadeRESUMO
BACKGROUND: Effective medical therapies are lacking for the treatment of neurofibromatosis type 1-related plexiform neurofibromas, which are characterized by elevated RAS-mitogen-activated protein kinase (MAPK) signaling. METHODS: We conducted a phase 1 trial of selumetinib (AZD6244 or ARRY-142886), an oral selective inhibitor of MAPK kinase (MEK) 1 and 2, in children who had neurofibromatosis type 1 and inoperable plexiform neurofibromas to determine the maximum tolerated dose and to evaluate plasma pharmacokinetics. Selumetinib was administered twice daily at a dose of 20 to 30 mg per square meter of body-surface area on a continuous dosing schedule (in 28-day cycles). We also tested selumetinib using a mouse model of neurofibromatosis type 1-related neurofibroma. Response to treatment (i.e., an increase or decrease from baseline in the volume of plexiform neurofibromas) was monitored by using volumetric magnetic resonance imaging analysis to measure the change in size of the plexiform neurofibroma. RESULTS: A total of 24 children (median age, 10.9 years; range, 3.0 to 18.5) with a median tumor volume of 1205 ml (range, 29 to 8744) received selumetinib. Patients were able to receive selumetinib on a long-term basis; the median number of cycles was 30 (range, 6 to 56). The maximum tolerated dose was 25 mg per square meter (approximately 60% of the recommended adult dose). The most common toxic effects associated with selumetinib included acneiform rash, gastrointestinal effects, and asymptomatic creatine kinase elevation. The results of pharmacokinetic evaluations of selumetinib among the children in this trial were similar to those published for adults. Treatment with selumetinib resulted in confirmed partial responses (tumor volume decreases from baseline of ≥20%) in 17 of the 24 children (71%) and decreases from baseline in neurofibroma volume in 12 of 18 mice (67%). Disease progression (tumor volume increase from baseline of ≥20%) has not been observed to date. Anecdotal evidence of decreases in tumor-related pain, disfigurement, and functional impairment was observed. CONCLUSIONS: Our early-phase data suggested that children with neurofibromatosis type 1 and inoperable plexiform neurofibromas benefited from long-term dose-adjusted treatment with selumetinib without having excess toxic effects. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01362803 .).
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Benzimidazóis/administração & dosagem , Benzimidazóis/farmacocinética , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Neurofibroma Plexiforme/tratamento farmacológico , Neurofibromatose 1/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacocinética , Adolescente , Animais , Benzimidazóis/efeitos adversos , Criança , Pré-Escolar , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Camundongos , Neurofibroma Plexiforme/diagnóstico por imagem , Inibidores de Proteínas Quinases/efeitos adversosRESUMO
Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder affecting about 1 in 3,500 individuals. Chronic pain is commonly reported among individuals with NF1 and plexiform neurofibroma tumors (PNs). Acceptance and Commitment Therapy (ACT), an empirically supported method for addressing chronic pain, helps individuals re-focus on valued relationships and activities. This pilot study investigated the feasibility and preliminary efficacy of a brief ACT workshop in the NF1 population. Eligible participants included adolescents and young adults (AYA; 12-21 years) with NF1 and chronic pain that interfered with daily functioning and their parents. Patients and parents completed baseline measures of pain interference, pain intensity, functional disability, pain acceptance, depression, and anxiety. Then, AYA and parents participated separately in a 2-day small-group ACT workshop. A telephone booster session occurred 1 month post-intervention. Three-month post-treatment measures were completed by mail. Ten adolescents (4 males; M age = 16.9 years) and seven parents provided baseline and 3-month data. Mean satisfaction with the study was moderate to high (3.9 for patients and 4.6 for parents on a 1-5 scales). Patients and parents reported significant declines in patients' pain interference at 3 months post-treatment. Patient-reported pain intensity significantly declined from baseline to 3 months. Parents reported marginally greater acceptance of their child's pain. No changes emerged in functional ability or mood. Preliminary findings suggest that a brief ACT group intervention is feasible and may help AYA with NF1 and PNs cope with their chronic pain, although larger randomized studies are needed to confirm treatment efficacy. © 2016 Wiley Periodicals, Inc.
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Terapia de Aceitação e Compromisso , Dor Crônica/terapia , Neurofibromatose 1/terapia , Terapia de Aceitação e Compromisso/métodos , Adolescente , Adulto , Criança , Dor Crônica/diagnóstico , Feminino , Humanos , Masculino , Adesão à Medicação , Medição da Dor , Pais , Projetos Piloto , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
The physical manifestations of neurofibromatosis type 1 (NF1) can cause chronic pain. This study investigated the impact of pain in youth with NF1 and plexiform neurofibromas (PNs) and its relationship to disease factors, social-emotional functioning, and quality of life (QOL) within a biopsychosocial framework. Caregivers of 59 children and adolescents with NF1 and PNs (6-18 years), and 41 of these youth (10-18 years), completed questionnaires assessing social-emotional functioning and QOL, including an item on pain interference. Measures of disease severity included total PN volume by percent body weight and number of disease complications. Both caregiver (73%) and self-report (59%) ratings indicated that pain interferes with the child's daily functioning despite 33% taking pain medication. Based on caregivers' behavior ratings, more symptoms of anxiety and larger tumor volumes predicted greater pain interference, while greater pain interference, worse depressive symptoms, and more disease complications predicted poorer QOL. As rated by adolescents, more symptoms of anxiety predicted greater pain interference, while greater pain interference and social stress predicted poorer QOL. Further, social-emotional problems mediate the relationship between pain interference and QOL. Thus, pain interferes with daily functioning in the majority of youth with NF1 and PNs even when using pain medication. The impact of pain interference, disease severity, and particularly social-emotional problems on QOL highlights the interaction between physical and psychological states in NF1. Future research and treatment of pain in this population should utilize a biopsychosocial approach and involve multidisciplinary therapies including psychological interventions that target social-emotional functioning.
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Neurofibroma Plexiforme/patologia , Neurofibroma Plexiforme/psicologia , Neurofibromatose 1/patologia , Neurofibromatose 1/psicologia , Dor/psicologia , Adaptação Psicológica/fisiologia , Adolescente , Cuidadores/psicologia , Criança , Emoções/fisiologia , Feminino , Humanos , Masculino , Transtornos Mentais/patologia , Transtornos Mentais/psicologia , Neurofibroma Plexiforme/complicações , Neurofibromatose 1/complicações , Dor/etiologia , Dor/patologia , Qualidade de Vida , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
BACKGROUND: RAS is dysregulated in neurofibromatosis type 1 (NF1) related plexiform neurofibromas (PNs). The activity of tipifarnib, which blocks RAS signaling by inhibiting its farnesylation, was tested in children and young adults with NF1 and progressive PNs. METHODS: Patients aged 3-25 years with NF1-related PNs and imaging evidence of tumor progression were randomized in a double-blinded fashion to receive tipifarnib (200 mg/m(2) orally every 12 h) or placebo (phase A) and crossed over to the opposite treatment arm at the time of tumor progression (phase B). PN volumes were measured with MRI, and progression was defined as ≥20% volume increase. Time to progression (TTP) in phase A was the primary endpoint, and the trial was powered to detect whether tipifarnib doubled TTP compared with placebo. Toxicity, response, and quality of life were also monitored. RESULTS: Sixty-two patients were enrolled. Tipifarnib and placebo were well tolerated. On phase A, the median TTP was 10.6 months on the placebo arm and 19.2 months on the tipifarnib arm (P = .12; 1-sided). Quality of life improved significantly compared with baseline on the tipifarnib arm but not on the placebo arm. Volumetric tumor measurement detected tumor progression earlier than conventional 2-dimensional (WHO) and 1-dimensional (RECIST) methods. CONCLUSIONS: Tipifarnib was well tolerated but did not significantly prolong TTP of PNs compared with placebo. The randomized, flexible crossover design and volumetric PN assessment provided a feasible and efficient means of assessing the efficacy of tipifarnib. The placebo arm serves as an historical control group for phase 2 single-arm trials directed at progressive PNs.
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Antineoplásicos/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Farnesiltranstransferase/antagonistas & inibidores , Neurofibroma Plexiforme/tratamento farmacológico , Neurofibromatose 1/tratamento farmacológico , Quinolonas/uso terapêutico , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Cross-Over , Progressão da Doença , Método Duplo-Cego , Feminino , Humanos , Masculino , Resultado do Tratamento , Adulto JovemRESUMO
Youth with neurofibromatosis type 1 (NF1) have multiple, complex symptoms associated with physical, social-emotional, and cognitive difficulties. In addition, caring for a child with NF1 can be extremely challenging for parents. Since research with other chronic illness populations suggests that social support, including internet support groups (ISGs), can be beneficial, this survey study aimed to determine the attitudes and preferences of adolescents and young adults with NF1 and parents of a child with NF1 regarding ISGs. Thirty patients and 30 caregivers completed a 24-item survey about ISGs. Many patients and parents are not aware of any ISGs for NF1, but are interested in using one in the future for a variety of reasons, including to get answers to their questions about NF1, to find out about research studies, and to discuss problems and concerns about NF1. Specific concerns of interest include physical, social-emotional, and cognitive aspects of NF1. ISGs have potential as a social support intervention within the NF1 community. ISGs for the NF1 population should include patients with NF1 (or parents of children with NF1) as well as a health professional, and both chat rooms and discussion boards likely would be well-received.
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Atitude , Internet , Neurofibromatose 1/psicologia , Grupos de Autoajuda , Adolescente , Adulto , Humanos , Adulto JovemRESUMO
PURPOSE: To describe the visual outcomes and volumetric magnetic resonance imaging (3D MRI) in children with neurofibromatosis type 1 (NF1) and orbitotemporal plexiform neurofibromas. DESIGN: Multicenter retrospective case series. METHODS: Two institutions with dedicated NF1 clinical research programs queried their established clinical databases for children with orbitotemporal plexiform neurofibromas. Visual acuity, refractive error, ambylopia, and treatment history were abstracted. Extent of orbitotemporal plexiform neurofibroma involvement was assessed clinically and with 3D MRI analysis. Children with optic pathway gliomas or ocular causes of decreased visual acuity (ie, cataracts, glaucoma) other than strabismus or anisometropia were excluded. RESULTS: Twenty-one children met inclusion criteria (median age 8 years, range 0.33-23 years). Orbitotemporal plexiform neurofibroma location was classified as isolated eyelid (n = 6), eyelid and orbit (n = 7), orbit and temporal region (n = 7), or diffuse orbit (n = 1). Three subjects had bilateral orbital involvement. Amblyopia secondary to the orbitotemporal plexiform neurofibroma was present in 13 subjects (62%) and was caused by strabismus (n = 2, 10%), occlusion from ptosis (n = 9, 43%), or anisometropia (n = 9, 43%), or a combination of factors (n = 6, 29%). MRI-derived volumes were measured in 19 subjects (median 41.8 mL, range 2.7-754 mL). All subjects with amblyopia had orbitotemporal plexiform neurofibroma volumes greater than 10 mL. CONCLUSION: In our series, amblyopia occurs in more than half of NF1 children with orbitotemporal plexiform neurofibromas, most commonly because of ptosis and anisometropia. The 3D MRI analysis allowed for sensitive measurement of orbitotemporal plexiform neurofibroma size, and larger volumes were associated with development of amblyopia.