RESUMO
The transcription factor HOXB4 not only plays a role during nephrogenesis, but displays also oncogenic characteristics in different malignant neoplasms. An in-silico analysis revealed HOXB4 as a new target of microRNA-23a (miR-23a). Nephroblastomas are malignant embryonal renal neoplasms of childhood resembling developing kidney morphologically and genetically. In our study we verified HOXB4 as a target of miR-23a and furthermore examined the expression of HOXB4 and miR-23a in nephroblastomas. We investigated binding of miR-23a to the 3'UTR of HOXB4 by a luciferase assay. Effects on protein levels of HOXB4 were analysed in Western blot experiments. Expression of HOXB4 in nephroblastomas was assessed by quantitative REALtime PCR (qRT PCR) and immunohistochemistry. The luciferase reporter assay showed a statistically significant downregulation of activity by 72,5% demonstrating direct binding of miR-23a to the 3'UTR of HOXB4. In addition, miR-23a reduced the protein expression of HOXB4 statistically significantly by 65.1%. All 21 nephroblastomas investigated had statistically significantly decreased expression levels of miR-23a. A high level of HOXB4 mRNA was found in five out of 33 nephroblastomas including mixed, blastema-type and stroma-type tumors. Protein expression of HOXB4 was stronger in 15 out of 27 nephroblastomas of all subtypes in a semiquantitative comparison to normal kidney parenchyma. Our study demonstrates for the first time the regulation of HOXB4 by miR-23a. In comparison to mature kidney, nephroblastomas had low levels of miR-23a, and in a majority of them a stronger protein expression in comparison to mature kidney was found.
Assuntos
Proteínas de Homeodomínio/genética , Neoplasias Renais/genética , MicroRNAs/genética , Fatores de Transcrição/genética , Tumor de Wilms/genética , Regiões 3' não Traduzidas , Apoptose , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/patologiaRESUMO
This study was undertaken to investigate the evolution of clinical features between onset of symptoms and diagnosis in children with brain tumours and to identify ways of shortening the time to diagnosis. One hundred and thirty-nine children with a brain tumour were recruited from four UK paediatric neuro-oncology centres. Children had a median of one symptom or sign at symptom onset and six by diagnosis. The symptoms and/or signs experienced at symptom onset and at diagnosis were as follows: headache in 55 and 81 children, nausea and vomiting in 39 and 88 children, motor system abnormalities in 31 and 93 children, cranial nerve palsies in 24 and 75 children, visual system abnormalities in 23 and 96 children, endocrine or growth abnormalities in 10 and 35 children and behavioural change in 4 and 55 children. The median time between symptom onset and diagnosis (symptom interval) was 3.3 months. A longer symptom interval was associated with head tilt, cranial nerve palsies, endocrine and growth abnormalities and reduced visual acuity. More than half of children with brain tumours developed problems with vision and more than a third developed motor problems, cranial nerve palsies, behavioural change, or nausea and vomiting between symptom onset and diagnosis.
Assuntos
Neoplasias Encefálicas/diagnóstico , Progressão da Doença , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Diagnóstico Tardio , Detecção Precoce de Câncer , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Modelos de Riscos Proporcionais , Encaminhamento e Consulta , Estudos Retrospectivos , Fatores de TempoRESUMO
BACKGROUND: Epidemiological studies and anecdotal reports suggest a possible link between household use of hard water and atopic eczema. We sought to test whether installation of an ion-exchange water softener in the home can improve eczema in children. METHODS AND FINDINGS: This was an observer-blind randomised trial involving 336 children (aged 6 months to 16 years) with moderate/severe atopic eczema. All lived in hard water areas (≥200 mg/l calcium carbonate). Participants were randomised to either installation of an ion-exchange water softener plus usual eczema care, or usual eczema care alone. The primary outcome was change in eczema severity (Six Area Six Sign Atopic Dermatitis Score, SASSAD) at 12 weeks, measured by research nurses who were blinded to treatment allocation. Analysis was based on the intent-to-treat population. Eczema severity improved for both groups during the trial. The mean change in SASSAD at 12 weeks was -5.0 (20% improvement) for the water softener group and -5.7 (22% improvement) for the usual care group (mean difference 0.66, 95% confidence interval -1.37 to 2.69, pâ=â0.53). No between-group differences were noted in the use of topical corticosteroids or calcineurin inhibitors. CONCLUSIONS: Water softeners provided no additional benefit to usual care in this study population. Small but statistically significant differences were found in some secondary outcomes as reported by parents, but it is likely that such improvements were the result of response bias, since participants were aware of their treatment allocation. A detailed report for this trial is also available at http://www.hta.ac.uk. TRIAL REGISTRATION: Current Controlled Trials ISRCTN71423189 Please see later in the article for the Editors' Summary.
Assuntos
Eczema/terapia , Abrandamento da Água , Adolescente , Banhos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , MasculinoRESUMO
BACKGROUND: The views and clinical practice of children's cancer units were surveyed regarding management of central venous catheter (CVC) occlusion (CVC-occlusion), CVC-related thrombosis (CVC-thrombosis) and thromboembolism (CVC-thromboembolism). PROCEDURE: A questionnaire was sent to all 22 United Kingdom Children's Cancer Study Group centres, requesting information about their views of the importance of, and their practices regarding, prophylaxis, diagnosis and treatment of CVC-occlusion/thrombosis. RESULTS: Twenty (91%) centres responded. Eighty percent, 80% and 70%, respectively, stated that CVC-occlusion, CVC-thrombosis and CVC-thromboembolism were clinically important concerns. All centres used heparinised saline flushes as prophylaxis against CVC-occlusion, with little variation (=30% centres) in frequency, volume and heparin concentration. Symptoms or signs suggesting partial CVC-occlusion, total CVC-occlusion, or CVC-thrombosis/thromboembolism were always investigated in 20%, 55% and 85% of centres, respectively, but with considerable variability in the nature and sequence of investigations performed, which included (depending on the clinical scenario) chest X-ray, contrast linography or venography, ultrasonography, echocardiography and magnetic resonance venography. A fibrinolytic lock was administered before investigation of CVC-occlusion in 75% of centres. Although 45%, 60% and 80%, respectively, always treated partial CVC-occlusion, total CVC-occlusion or CVC-thrombosis/thromboembolism, the type and order of treatments differed greatly between centres, especially for CVC-thrombosis/thromboembolism, in which CVC removal, systemic anticoagulation (heparin or warfarin), local or systemic fibrinolysis, or thrombectomy were performed in at least some centres. CONCLUSIONS: The clinical practice of UKCCSG centres regarding prevention, investigation and treatment of CVC-occlusion/thrombosis varies greatly. Additional trials should facilitate development of evidence-based guidelines.
Assuntos
Cateterismo Venoso Central/efeitos adversos , Tromboembolia/prevenção & controle , Tromboembolia/terapia , Trombose/prevenção & controle , Trombose/terapia , Adulto , Antineoplásicos/administração & dosagem , Criança , Humanos , Neoplasias/tratamento farmacológico , Inquéritos e Questionários , Tromboembolia/etiologia , Trombose/etiologiaRESUMO
In the last decade children's blood lead levels have fallen significantly in a number of countries, and current mean levels in developed countries are in the region of 3 Mu g/dL. Despite this reduction, childhood lead poisoning continues to be a major public health problem for certain at-risk groups of children, and concerns remain over the effects of lead on intellectual development in infants and children. The evidence for lowered cognitive ability in children exposed to lead has come largely from prospective epidemiologic studies. The current World Health Organization/Centers for Disease Control and Prevention blood level of concern reflects this and stands at 10 Mu g/dL. However, a recent study on a cohort of children whose lifetime peak blood levels were consistently less than 10 Mu g/dL has extended the association of blood lead and intellectual impairment to lower levels of lead exposure and suggests there is no safety margin at existing exposures. Because of the importance of this finding, we reviewed this study in detail along with other recent developments in the field of low-level lead exposure and children's cognitive development. We conclude that these findings are important scientifically, and efforts should continue to reduce childhood exposure. However, from a public health perspective, exposure to lead should be seen within the many other risk factors impacting on normal childhood development, in particular the influence of the learning environment itself. Current lead exposure accounts for a very small amount of variance in cognitive ability (1-4%), whereas social and parenting factors account for 40% or more.
Assuntos
Desenvolvimento Infantil , Proteção da Criança , Transtornos Cognitivos/etiologia , Exposição Ambiental , Intoxicação por Chumbo/complicações , Criança , Pré-Escolar , Estudos Transversais , Relação Dose-Resposta a Droga , Humanos , Inteligência , Poder Familiar , Estudos Prospectivos , Saúde Pública , Valores de Referência , Medição de Risco , Comportamento SocialRESUMO
By comparing several studies we identified a possible deregulation of the transcription factors PBX2 (pre-B-cell leukemia homeobox 2) and one of its binding partners, MEIS1 (Meis homeobox 1) in nephroblastomas. The regulation of MEIS1 is complex, and its expression is known to be influenced by changes of promoter methylation and binding of microRNA-204 (miR-204). Therefore, in our study, we assessed the expression of MEIS1 and PBX2 and the factors regulating expression of MEIS1 in nephroblastomas. MEIS1 and PBX2 messenger RNA (mRNA) and protein levels were investigated by quantitative real-time-polymerase chain reaction (qRT-PCR) and immunohistochemistry. Promoter methylation of MEIS1 was evaluated using a methylation-specific PCR assay. Expression levels of miR-204 were examined by qRT-PCR. Eighteen of 21 nephroblastomas showed a high level of MEIS1 mRNA, and 22 of 26 samples had a specific nuclear protein expression. MicroRNA-204 had a statistically significantly lower expression in all nephroblastomas investigated compared with renal parenchyma, but no change of MEIS1 promoter methylation status was noted. Eleven of 23 nephroblastomas had a high expression of PBX2 mRNA, and 15 of 23 samples had a specific nuclear protein expression was noted. In our study, we demonstrated an expression of MEIS1 and its binding partner PBX2 in most nephroblastomas. The statistically significantly lower expression of miR-204 in all nephroblastomas investigated might point to an involvement of miR-204 in the regulation of MEIS1 in nephroblastomas.
Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Proteínas de Homeodomínio/biossíntese , Neoplasias Renais/genética , MicroRNAs/biossíntese , Proteínas de Neoplasias/biossíntese , Tumor de Wilms/genética , Humanos , Imuno-Histoquímica , Neoplasias Renais/metabolismo , Proteína Meis1 , Proteínas Proto-Oncogênicas/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tumor de Wilms/metabolismoRESUMO
The putative tumor suppressor protein spinophilin has been recently involved in the pathogenesis of lung, liver, and other types of cancer. Previous studies also indicate that a loss of spinophilin in combination with functional impairment of p53 drives tumor progression. To date, no data exist about the role of spinophilin in head and neck squamous cell carcinoma (HNSCC). In the present study, we evaluated spinophilin and p53 expression by immunohistochemistry in 85 patients with nonmetastatic HNSCC. Kaplan-Meier curves and multivariate Cox proportional models were used to define the prognostic relevance of spinophilin for patients with HNSCC. Overall, immunoreactivity for spinophilin was reduced in 40 tumors (47%). Nine cases (10.5%) showed complete loss of spinophilin. Kaplan-Meier curve analysis demonstrated that reduced spinophilin expression is associated with poor overall survival (P = .022). Concomitant analysis of spinophilin and p53 further showed that patients with reduced spinophilin expression and nuclear p53 staining have a significantly decreased overall survival (hazard ratio, 1.96; 95% confidence interval, 1.06-3.61; P = .030). In conclusion, the combination of reduced spinophilin expression and nuclear p53 staining indicates a poor prognosis in HNSCC patients. Based on our results, spinophilin might play a previously unrecognized role in the pathogenesis of HNSCC.
Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/mortalidade , Proteínas dos Microfilamentos/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Idoso , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Proteínas dos Microfilamentos/análise , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/análise , Prognóstico , Modelos de Riscos Proporcionais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/biossínteseRESUMO
Embryonal renal mesenchyme contains pluripotent progenitor cells characterized by expression of SIX2, which suppresses cellular differentiation. Additionally hypomethylation of the promotor region in renal neoplasms indicates a role of SIX2 in tumorigenesis. This study focuses therefore on the investigation of SIX2 in different renal neoplasms and the mode and consequences of SIX2 activation. Expression of SIX2 was determined in renal cell carcinomas, nephroblastomas, and dysplastic kidneys using immunohistochemistry and quantitative real-time polymerase chain reaction. Its potential mode of activation was assessed by measuring upstream activators by quantitative real-time polymerase chain reaction and the level of methylation of the promoter region by quantitative DNA methylation analysis. Consequences of SIX2 activation were investigated by overexpressing SIX2 in a cell line. Forty-seven of 49 renal clear cell carcinomas showed nuclear staining of SIX2, whereas all papillary carcinomas were negative. In nephroblastomas of various subtypes blastema showed a significant up-regulation (P < .01) and a strong nuclear protein expression of SIX2 in contrast to negative epithelial and mesenchymal areas. 11 cases of dysplastic kidneys were entirely negative. Upstream activators of SIX2 indicated an activation of the signal transduction pathway in most samples. No difference of promoter methylation status was observed between blastema and epithelial structures. A significantly higher percentage of cells in the S-phase and an increased migration were detected in the cell-line overexpressing SIX2. Our study suggests that activation of SIX2 might contribute to the pathogenesis of renal clear cell carcinomas and nephroblastomas. SIX2 also appears to be a valuable marker for minimal residual blastema contributing to the prognosis of nephroblastomas.
Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Proteínas de Homeodomínio/genética , Neoplasias Renais/genética , Rim Displásico Multicístico/genética , Proteínas do Tecido Nervoso/genética , Tumor de Wilms/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Criança , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Rim Displásico Multicístico/metabolismo , Rim Displásico Multicístico/patologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenótipo , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/patologia , Prognóstico , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Regulação para Cima , Tumor de Wilms/metabolismo , Tumor de Wilms/patologiaRESUMO
BACKGROUND: Following the successful introduction of five topic-specific research networks in the UK, the Comprehensive Local Research Network (CLRN) was established in 2008 in order to provide a blanket level of support across the whole country regardless of the clinical discipline. The role of the CLRN was to facilitate recruitment into clinical trials, and to encourage greater engagement in research throughout the National Health Service (NHS). METHODS: This report evaluates the impact of clinical research networks in supporting clinical trials in the UK, with particular reference to our experiences from two non-commercial dermatology trials. It covers our experience of engaging with the CLRN (and other research networks) using two non-commercial dermatology trials as case studies. We present the circumstances that led to our approach to the research networks for support, and the impact that this support had on the delivery of these trials. RESULTS: In both cases, recruitment was boosted considerably following the provision of additional support, although other factors such as the availability of experienced personnel, and the role of advertising and media coverage in promoting the trials were also important in translating this additional resource into increased recruitment. CONCLUSIONS: Recruitment into clinical trials is a complex task that can be influenced by many factors. A world-class clinical research infrastructure is now in place in England (with similar support available in Scotland and Wales), and it is the responsibility of the research community to ensure that this unique resource is used effectively and responsibly.
Assuntos
Pesquisa Biomédica/organização & administração , Dermatologia/organização & administração , Estudos Multicêntricos como Assunto , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto , Apoio à Pesquisa como Assunto/organização & administração , Antibacterianos/administração & dosagem , Pesquisa Biomédica/economia , Celulite (Flegmão)/prevenção & controle , Comportamento Cooperativo , Dermatologia/economia , Eczema/prevenção & controle , Humanos , Relações Interinstitucionais , Perna (Membro) , Estudos Multicêntricos como Assunto/economia , Objetivos Organizacionais , Avaliação de Programas e Projetos de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Pesquisadores/economia , Pesquisadores/organização & administração , Reino Unido , Abrandamento da ÁguaRESUMO
BACKGROUND: Brain tumours are the commonest solid tumour in children. Children with brain tumours are frequently unwell for months prior to diagnosis. A prolonged period between symptom onset and diagnosis is associated with increased morbidity. OBJECTIVE: To develop an evidence-based clinical guideline to support healthcare professionals in the identification, assessment and investigation of children presenting with symptoms and signs that could be due to a brain tumour. METHODS: A systematic literature review with a meta-analysis and cohort study provided the guideline evidence base. A multi-disciplinary workshop and Delphi consensus voting were used to translate the evidence into a clinical guideline. The results of the literature review and cohort study have been previously published. RESULTS: 20 healthcare professionals and parents participated in the workshop. 77 statements were generated detailing the presenting features of childhood brain tumours, factors that could be used to discriminate brain tumours from other less serious conditions and possible referral pathways for children with brain tumours. 156 healthcare professionals agreed to participate in the Delphi process; 112 completed the first round and 88 completed all three rounds (attrition rate 21%). 64 statements reached consensus. The final guideline comprises 76 recommendations advising on the symptomatology of childhood brain tumours, assessment of children who may have a brain tumour and recommendations for selection for and timing of central nervous system imaging. CONCLUSION: Implementation of this guideline may support clinicians in the identification and timely imaging of children with brain tumours. This may reduce the morbidity currently experienced by many children with brain tumours.
Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/complicações , Criança , Técnica Delphi , Deficiências do Desenvolvimento/etiologia , Medicina Baseada em Evidências/métodos , Transtornos da Cefaleia Secundários/etiologia , Humanos , Imageamento por Ressonância Magnética , Náusea/etiologia , Guias de Prática Clínica como Assunto , Fatores de Risco , Tomografia Computadorizada por Raios X , Vômito/etiologiaRESUMO
BACKGROUND: Suspicion of a CNS tumour is classically raised by symptoms of raised intracranial pressure, focal deficits (including seizures), or papilloedema. Development of guidelines is needed for the identification and referral of children who might have a CNS tumour. We did a systematic literature review and meta-analysis to identify the clinical presentation of childhood CNS tumours to provide evidence to support the development of guidelines to assist with the identification and referral for imaging of children who might have a central nervous system tumour. METHODS: Medline, Embase, and PubMed were searched for cohort studies and case series in children, published between January, 1991, and August, 2005, detailing the symptoms and signs at diagnosis of a CNS tumour. FINDINGS: 74 papers (n=4171) met the inclusion criteria. 56 symptoms and signs at diagnosis were identified, ranked by frequency, and clustered according to age, anatomical criteria, and genetic criteria. The most frequent symptoms and signs at diagnosis were: headache (33%), nausea and vomiting (32%), abnormalities of gait and coordination (27%), and papilloedema (13%) for intracranial tumours; macrocephaly (41%), nausea and vomiting (30%), irritability (24%), and lethargy (21%) for children aged under 4 years with intracranial tumours; reduced visual acuity (41%), exophthalmia (16%), and optic atrophy (15%) for children with an intracranial tumour and neurofibromatosis; nausea and vomiting (75%), headache (67%), abnormal gait and coordination (60%), and papilloedema (34%) for posterior fossa tumours; unspecified symptoms and signs of raised intracranial pressure (47%), seizures (38%), and papilloedema (21%) for supratentorial tumours; headache (49%), abnormal eye movements (21%), squint (21%), and nausea and vomiting (19%) for central brain tumours; abnormal gait and coordination (78%), cranial nerve palsies (52%), pyramidal signs (33%), headache (23%), and squint (19%) for brainstem tumours; and back pain (67%), abnormalities of gait and coordination (42%), spinal deformity (39%), focal weakness (21%), and sphincter disturbance (20%) for spinal-cord tumours. Other features noted were weight loss, growth failure, and precocious puberty. Symptoms of raised intracranial pressure were absent in more than half of children with brain tumours. Other neurological features were heterogeneous and related to tumour location. INTERPRETATION: Apart from raised intracranial pressure, motor and visual system abnormalities, weight loss, macrocephaly, growth failure, and precocious puberty also suggest presence of an intracranial tumour. Children with signs and symptoms that could result from a CNS tumour need a thorough visual and motor system examination and an assessment of growth and pubertal status. Occurrence of multiple symptoms and signs should alert clinicians to possible CNS tumours.