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1.
Genet Med ; 23(11): 2087-2095, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34262154

RESUMO

PURPOSE: Ataxia-Telangiectasia Mutated (ATM) has been implicated in the risk of several cancers, but establishing a causal relationship is often challenging. Although ATM single-nucleotide polymorphisms have been linked to melanoma, few functional alleles have been identified. Therefore, ATM impact on melanoma predisposition is unclear. METHODS: From 22 American, Australian, and European sites, we collected 2,104 familial, multiple primary (MPM), and sporadic melanoma cases who underwent ATM genotyping via panel, exome, or genome sequencing, and compared the allele frequency (AF) of selected ATM variants classified as loss-of-function (LOF) and variants of uncertain significance (VUS) between this cohort and the gnomAD non-Finnish European (NFE) data set. RESULTS: LOF variants were more represented in our study cohort than in gnomAD NFE, both in all (AF = 0.005 and 0.002, OR = 2.6, 95% CI = 1.56-4.11, p < 0.01), and familial + MPM cases (AF = 0.0054 and 0.002, OR = 2.97, p < 0.01). Similarly, VUS were enriched in all (AF = 0.046 and 0.033, OR = 1.41, 95% CI = 1.6-5.09, p < 0.01) and familial + MPM cases (AF = 0.053 and 0.033, OR = 1.63, p < 0.01). In a case-control comparison of two centers that provided 1,446 controls, LOF and VUS were enriched in familial + MPM cases (p = 0.027, p = 0.018). CONCLUSION: This study, describing the largest multicenter melanoma cohort investigated for ATM germline variants, supports the role of ATM as a melanoma predisposition gene, with LOF variants suggesting a moderate-risk.


Assuntos
Ataxia Telangiectasia , Melanoma , Proteínas Mutadas de Ataxia Telangiectasia/genética , Austrália , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Melanoma/genética
2.
Br J Dermatol ; 184(6): 1085-1093, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33270213

RESUMO

BACKGROUND: Melanoma aetiology has been proposed to have two pathways, which are determined by naevi and type of sun exposure and related to the anatomical site where melanoma develops. OBJECTIVES: We examined associations with melanoma by anatomical site for a comprehensive set of risk factors including pigmentary and naevus phenotypes, ultraviolet radiation exposure and polygenic risk. METHODS: We analysed harmonized data from 2617 people with incident first invasive melanoma and 975 healthy controls recruited through two population-based case-control studies in Australia and the UK. Questionnaire data were collected by interview using a single protocol, and pathway-specific polygenic risk scores were derived from DNA samples. We estimated adjusted odds ratios using unconditional logistic regression that compared melanoma cases at each anatomical site with all controls. RESULTS: When cases were compared with control participants, there were stronger associations for many naevi vs. no naevi for melanomas on the trunk, and upper and lower limbs than on the head and neck (P-heterogeneity < 0·001). Very fair skin (vs. olive/brown skin) was more weakly related to melanoma on the trunk than to melanomas at other sites (P-heterogeneity = 0·04). There was no significant difference by anatomical site for polygenic risk. Increased weekday sun exposure was positively associated with melanoma on the head and neck but not on other sites. CONCLUSIONS: We found evidence of aetiological heterogeneity for melanoma, supporting the dual pathway hypothesis. These findings enhance understanding of risk factors for melanoma and can guide prevention and skin examination education and practices.


Assuntos
Melanoma , Neoplasias Cutâneas , Austrália/epidemiologia , Humanos , Melanoma/etiologia , Melanoma/genética , Fatores de Risco , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/genética , Raios Ultravioleta
3.
Pediatr Surg Int ; 35(8): 829-834, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31201486

RESUMO

Although most children with Hirschsprung disease ultimately achieve functional and comfortable stooling, some will experience a variety of problems after pull-through surgery. The most common problems include soiling, obstructive symptoms, enterocolitis, and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative soiling in children with Hirschsprung disease. The American Pediatric Surgical Association Hirschsprung Disease Interest Group engaged in a literature review and group discussions. Expert consensus was then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with soiling symptoms following pull-through for Hirschsprung disease. Causes of soiling after pull-through are broadly categorized as abnormalities in sensation, abnormalities in sphincter control, and "pseudo-incontinence." A stepwise algorithm for the diagnosis and management of soiling after a pull-through for Hirschsprung disease is presented; it is our hope that this rational approach will facilitate treatment and optimize outcomes.


Assuntos
Algoritmos , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Incontinência Fecal/cirurgia , Doença de Hirschsprung/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Guias de Prática Clínica como Assunto , Criança , Incontinência Fecal/etiologia , Doença de Hirschsprung/complicações , Humanos , Período Pós-Operatório , Resultado do Tratamento
4.
J Eur Acad Dermatol Venereol ; 33(10): 1874-1885, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31087403

RESUMO

BACKGROUND: People at high risk of developing melanoma are usually identified by pigmentary and naevus phenotypes. OBJECTIVE: We examined whether associations of these phenotypes with melanoma risk differed by ambient sun exposure or participant characteristics in two population-based, case-control studies with comparable ancestry but different ambient sun exposure. METHODS: Data were analysed from 616 cases and 496 controls from the Australian Melanoma Family Study and 2012 cases and 504 controls from the Leeds (UK) case-control study. Questionnaire, interview and dermatological skin examination data were collected using the same measurement protocols. Relative risks were estimated as odds ratios using unconditional logistic regression, adjusted for potential confounders. RESULTS: Hair and skin colour were the strongest pigmentary phenotype risk factors. All associations of pigmentary phenotype with melanoma risk were similar across countries. The median number of clinically assessed naevi was approximately three times higher in Australia than Leeds, but the relative risks for melanoma associated with each additional common or dysplastic naevus were higher for Leeds than Australia, especially for naevi on the upper and lower limbs. Higher naevus counts on the head and neck were associated with a stronger relative risk for melanoma for women than men. The two countries had similar relative risks for melanoma based on self-reported naevus density categories, but personal perceptions of naevus number differed by country. There was no consistent evidence of interactions between phenotypes on risk. CONCLUSIONS: Classifying people at high risk of melanoma based on their number of naevi should ideally take into account their country of residence, type of counts (clinical or self-reported), body site on which the naevus counts are measured and sex. The presence of naevi may be a stronger indicator of a genetic predisposition in the UK than in Australia based on less opportunity for sun exposure to influence naevus development.


Assuntos
Exposição Ambiental , Melanoma/etnologia , Nevo Pigmentado/etnologia , Neoplasias Cutâneas/etnologia , Pigmentação da Pele , Luz Solar , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Estudos de Casos e Controles , Extremidades , Feminino , Cor de Cabelo , Humanos , Masculino , Pessoa de Meia-Idade , Nevo Pigmentado/patologia , Fenótipo , Medição de Risco , Fatores de Risco , Fatores Sexuais , Neoplasias Cutâneas/patologia , Carga Tumoral , Reino Unido/epidemiologia , População Branca , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-28884943

RESUMO

BACKGROUND: Current efforts to develop stem cell therapy as a novel treatment for neurointestinal diseases are limited by the unavailability of a model system to study cell transplantation in the human intestine. We propose that xenograft models support enteric nervous system (ENS) development in the fetal human intestine when transplanted into mice subcutaneously or intra-abdominally. METHODS: Fetal human small and large intestine were grafted onto the small intestinal mesentery and into the subcutaneous tissue of immunodeficient mice for up to 4 months. Intestinal cytoarchitecture and ENS development were studied using immunohistochemistry. KEY RESULTS: In both abdominal and subcutaneous grafts, the intestine developed normally with formation of mature epithelial and mesenchymal layers. The ENS was patterned in two ganglionated plexuses containing enteric neurons and glia, including cholinergic and nitrergic neuronal subtypes. c-Kit-immunoreactive interstitial cells of Cajal were present in the gut wall. CONCLUSIONS & INFERENCES: Abdominal xenografts represent a novel model that supports the growth and development of fetal human intestine. This in vivo approach will be a useful method to study maturation of the ENS, the pathophysiology of neurointestinal diseases, and the long-term survival and functional differentiation of neuronal stem cells for the treatment of enteric neuropathies.


Assuntos
Abdome/fisiologia , Sistema Nervoso Entérico/fisiologia , Intestinos/fisiologia , Intestinos/transplante , Tela Subcutânea/fisiologia , Transplante Heterólogo , Animais , Sistema Nervoso Entérico/citologia , Transplante de Tecido Fetal/métodos , Humanos , Intestinos/citologia , Camundongos SCID
6.
Ann Oncol ; 28(9): 2086-2093, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28911061

RESUMO

The International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI) have initiated a series of cancer-focused seminars [Scelo G, Hofmann JN, Banks RE et al. International cancer seminars: a focus on kidney cancer. Ann Oncol 2016; 27(8): 1382-1385]. In this, the second seminar, IARC and NCI convened a workshop in order to examine the state of the current science on esophageal squamous cell carcinoma etiology, genetics, early detection, treatment, and palliation, was reviewed to identify the most critical open research questions. The results of these discussions were summarized by formulating a series of 'difficult questions', which should inform and prioritize future research efforts.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Internacionalidade , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Detecção Precoce de Câncer , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago , Humanos , Fatores de Risco
7.
Pediatr Surg Int ; 33(5): 523-526, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28180937

RESUMO

Although most children with Hirschsprung disease ultimately do well, many experience a variety of ongoing problems after pull-through surgery. The most common include obstructive symptoms, soiling, enterocolitis and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative obstructive symptoms in children with Hirschsprung disease. The American Pediatric Surgical Association Board of Governors established a Hirschsprung Disease Interest Group. Group discussions, literature review and expert consensus were then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with obstructive symptoms following pull-through for Hirschsprung disease. Causes of obstructive symptoms post-pull-through include mechanical obstruction; persistent or acquired aganglionosis, hypoganglionosis, or transition zone pull-through; internal sphincter achalasia; disordered motility in the proximal intestine that contains ganglion cells; or functional megacolon caused by stool-holding behavior. An algorithm for the diagnosis and management of obstructive symptoms after a pull-through for Hirschsprung disease is presented. A stepwise, logical approach to the diagnosis and management of patients experiencing obstructive symptoms following pull-through for Hirschsprung disease can facilitate treatment. Level of evidence V.


Assuntos
Doença de Hirschsprung/cirurgia , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/terapia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Toxinas Botulínicas/uso terapêutico , Criança , Pré-Escolar , Enema , Feminino , Doença de Hirschsprung/complicações , Humanos , Lactente , Obstrução Intestinal/etiologia , Masculino , Guias de Prática Clínica como Assunto
8.
Diabetes Obes Metab ; 18(5): 519-27, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26876427

RESUMO

AIMS: To examine whether co-administration of intestinal alkaline phosphatase (IAP) with antibiotics early in life may have a preventive role against metabolic syndrome (MetS) in mice. METHODS: A total of 50 mice were allocated to four treatment groups after weaning. Mice were treated with azithromycin (AZT) ± IAP, or with no AZT ± IAP, for three intermittent 7-day cycles. After the last treatment course, the mice were administered a regular chow diet for 5 weeks and subsequently a high-fat diet for 5 weeks. Body weight, food intake, water intake, serum lipids, glucose levels and liver lipids were compared. 16S rRNA gene pyrosequencing was used to determine the differences in microbiome composition. RESULTS: Exposure to AZT early in life rendered mice susceptible to MetS in adulthood. Co-administration of IAP with AZT completely prevented this susceptibility by decreasing total body weight, serum lipids, glucose levels and liver lipids to the levels of control mice. These effects of IAP probably occur as a result of changes in the composition of specific bacterial taxa at the genus and species levels (e.g. members of Anaeroplasma and Parabacteroides). CONCLUSIONS: Co-administration of IAP with AZT early in life prevents mice from susceptibility to the later development of MetS. This effect is associated with alterations in the composition of the gut microbiota. IAP may represent a novel treatment against MetS in humans.


Assuntos
Fosfatase Alcalina/uso terapêutico , Antibacterianos/efeitos adversos , Azitromicina/efeitos adversos , Suplementos Nutricionais , Disbiose/prevenção & controle , Mucosa Intestinal/enzimologia , Síndrome Metabólica/prevenção & controle , Acholeplasma/classificação , Acholeplasma/efeitos dos fármacos , Acholeplasma/crescimento & desenvolvimento , Acholeplasma/isolamento & purificação , Fosfatase Alcalina/efeitos adversos , Animais , Bacteroides/classificação , Bacteroides/efeitos dos fármacos , Bacteroides/crescimento & desenvolvimento , Bacteroides/isolamento & purificação , Bovinos , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Disbiose/induzido quimicamente , Disbiose/microbiologia , Disbiose/fisiopatologia , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/etiologia , Síndrome Metabólica/microbiologia , Camundongos Endogâmicos C57BL , Tipagem Molecular , Obesidade/complicações , Obesidade/etiologia , Obesidade/microbiologia , Obesidade/prevenção & controle , Desmame , Aumento de Peso/efeitos dos fármacos
9.
Neurogastroenterol Motil ; 28(4): 498-512, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26685978

RESUMO

BACKGROUND: Transplanting autologous patient-derived enteric neuronal stem/progenitor cells (ENSCs) is an innovative approach to replacing missing enteric neurons in patients with Hirschsprung disease (HSCR). Using autologous cells eliminates immunologic and ethical concerns raised by other cell sources. However, whether postnatal aganglionic bowel is permissive for transplanted ENSCs and whether ENSCs from HSCR patients can be successfully isolated, cultured, and transplanted in vivo remains unknown. METHODS: ENSCs isolated from the ganglionic intestine of Ednrb(-/-) mice (HSCR-ENSCs) were characterized immunohistochemically and evaluated for their capacity to proliferate and differentiate in vitro. Fluorescently labeled ENSCs were co-cultured ex vivo with aganglionic Ednrb(-/-) colon. For in vivo transplantation, HSCR-ENSCs were labeled with lentivirus expressing green fluorescent protein (GFP) and implanted into aganglionic embryonic chick gut in ovo and postnatal aganglionic Ednrb(-/-) rectum in vivo. KEY RESULTS: HSCR-ENSCs maintain normal capacity self-renewal and neuronal differentiation. Moreover, the Ednrb(-/-) aganglionic environment is permissive to engraftment by wild-type ENSCs ex vivo and supports migratrion and neuroglial differentiation of these cells following transplantation in vivo. Lentiviral GFP-labeled HSCR-ENSCs populated embryonic chick hindgut and postnatal colon of Ednrb(-/-) HSCR, with cells populating the intermuscular layer and forming enteric neurons and glia. CONCLUSIONS & INFERENCES: ENSCs can be isolated and cultured from mice with HSCR, and transplanted into the aganglionic bowel of HSCR littermates to generate enteric neuronal networks. These results in an isogenic model establish the potential of using autologous-derived stem cells to treat HSCR and other intestinal neuropathies.


Assuntos
Doença de Hirschsprung , Células-Tronco Neurais/transplante , Neuroglia/citologia , Neurônios/citologia , Transplante de Células-Tronco/métodos , Animais , Modelos Animais de Doenças , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transplante Isogênico/métodos
10.
Neurogastroenterol Motil ; 27(10): 1509-14, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26190543

RESUMO

BACKGROUND: Transplantation of enteric neural stem cells (ENSC) holds promise as a potential therapy for enteric neuropathies, including Hirschsprung disease. Delivery of transplantable cells via laparotomy has been described, but we propose a novel, minimally invasive endoscopic method of cell delivery. METHODS: Enteric neural stem cells for transplantation were cultured from dissociated gut of postnatal donor mice. Twelve recipient mice, including Ednrb(-/-) mice with distal colonic aganglionosis, underwent colonoscopic injection of ENSC under direct vision using a 30-gauge Hamilton needle passed through a rigid cystoureteroscope. Cell engraftment, survival, and neuroglial differentiation were studied 1-4 weeks after the procedure. KEY RESULTS: All recipient mice tolerated the procedure without complications and survived to sacrifice. Transplanted cells were found within the colonic wall in 9 of 12 recipient mice with differentiation into enteric neurons and glia. CONCLUSIONS & INFERENCES: Endoscopic injection of ENSC is a safe and reliable method for cell delivery, and can be used to deliver a large number of cells to a specific area of disease. This minimally invasive endoscopic approach may prove beneficial to future human applications of cell therapy for neurointestinal disease.


Assuntos
Colonoscopia/métodos , Sistema Nervoso Entérico/citologia , Doença de Hirschsprung/terapia , Células-Tronco Neurais/transplante , Animais , Modelos Animais de Doenças , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptor de Endotelina B
11.
Neurogastroenterol Motil ; 25(5): 420-6, e299, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23421516

RESUMO

BACKGROUND: The metabolic pathways associated with colonic motility are unknown. To identify potential metabolic targets for treatment of constipation, we examined the metabolic profile before and after a meal challenge in a cohort of children with constipation and determined its relationship with postprandial colon motility patterns. METHODS: In this prospective study, 187 metabolites were measured by liquid chromatography-mass spectrometry at multiple time points before and after a standardized meal in constipated children undergoing a colon manometry. Postprandial metabolite levels were compared with baseline and also correlated with multiple manometric measurements, including the number, frequency, and amplitude of pressure peaks as well as the motility index (MI). KEY RESULTS: A total of 20 subjects were included (mean age 13.1 ± 3.4 years). No significant metabolite changes were observed at 10 min after the meal, whereas 16 amino acid and 22 lipid metabolites had significant (P < 0.005) postprandial changes, including decreases in methylhistamine, histamine, and GABA, by 60 min. Correlations were observed between normal and abnormal postprandial motility patterns and changes in specific metabolites, including glycerol, carnosine, alanine, asparagine, cytosine, choline, phosphocholine, thyroxine, and triiodothyronine. Interestingly, subjects without the normal postprandial increase in area under the curve (AUC), had markedly increased levels of kynurenic acid and adenosyl-homocysteine. CONCLUSIONS & INFERENCES: This is the first study to examine postprandial metabolic changes in children and also to correlate changes in specific metabolites with colonic motility. The results suggest possible metabolic pathways associated with motility and identify potential targets for the treatment of constipation.


Assuntos
Constipação Intestinal/metabolismo , Motilidade Gastrointestinal/fisiologia , Metabolômica , Período Pós-Prandial/fisiologia , Adolescente , Criança , Cromatografia Líquida , Colo , Constipação Intestinal/fisiopatologia , Feminino , Humanos , Masculino , Manometria , Espectrometria de Massas
12.
Br J Cancer ; 108(6): 1378-86, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23361049

RESUMO

BACKGROUND: The chromosome 9p21.3 region has been implicated in the pathogenesis of multiple cancers. METHODS: We systematically examined up to 203 tagging SNPs of 22 genes on 9p21.3 (19.9-32.8 Mb) in eight case-control studies: thyroid cancer, endometrial cancer (EC), renal cell carcinoma, colorectal cancer (CRC), colorectal adenoma (CA), oesophageal squamous cell carcinoma (ESCC), gastric cardia adenocarcinoma and osteosarcoma (OS). We used logistic regression to perform single SNP analyses for each study separately, adjusting for study-specific covariates. We combined SNP results across studies by fixed-effect meta-analyses and a newly developed subset-based statistical approach (ASSET). Gene-based P-values were obtained by the minP method using the Adaptive Rank Truncated Product program. We adjusted for multiple comparisons by Bonferroni correction. RESULTS: Rs3731239 in cyclin-dependent kinase inhibitors 2A (CDKN2A) was significantly associated with ESCC (P=7 × 10(-6)). The CDKN2A-ESCC association was further supported by gene-based analyses (Pgene=0.0001). In the meta-analyses by ASSET, four SNPs (rs3731239 in CDKN2A, rs615552 and rs573687 in CDKN2B and rs564398 in CDKN2BAS) showed significant associations with ESCC and EC (P<2.46 × 10(-4)). One SNP in MTAP (methylthioadenosine phosphorylase) (rs7023329) that was previously associated with melanoma and nevi in multiple genome-wide association studies was associated with CRC, CA and OS by ASSET (P=0.007). CONCLUSION: Our data indicate that genetic variants in CDKN2A, and possibly nearby genes, may be associated with ESCC and several other tumours, further highlighting the importance of 9p21.3 genetic variants in carcinogenesis.


Assuntos
Biomarcadores Tumorais/genética , Cromossomos Humanos Par 9/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Metanálise como Assunto , Prognóstico
13.
Neurogastroenterol Motil ; 25(1): 61-9.e7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22998406

RESUMO

BACKGROUND: Neuronal stem cells (NSCs) are promising for neurointestinal disease therapy. Although NSCs have been isolated from intestinal musclularis, their presence in mucosa has not been well described. Mucosa-derived NSCs are accessible endoscopically and could be used autologously. Brain-derived Nestin-positive NSCs are important in endogenous repair and plasticity. The aim was to isolate and characterize mucosa-derived NSCs, determine their relationship to Nestin-expressing cells and to demonstrate their capacity to produce neuroglial networks in vitro and in vivo. METHODS: Neurospheres were generated from periventricular brain, colonic muscularis (Musc), and mucosa-submucosa (MSM) of mice expressing green fluorescent protein (GFP) controlled by the Nestin promoter (Nestin-GFP). Neuronal stem cells were also grown as adherent colonies from intestinal mucosal organoids. Their differentiation potential was assessed using immunohistochemistry using glial and neuronal markers. Brain and gut-derived neurospheres were transplanted into explants of chick embryonic aneural hindgut to determine their fate. KEY RESULTS: Musc- and MSM-derived neurospheres expressed Nestin and gave rise to cells of neuronal, glial, and mesenchymal lineage. Although Nestin expression in tissue was mostly limited to glia co-labelled with glial fibrillary acid protein (GFAP), neurosphere-derived neurons and glia both expressed Nestin in vitro, suggesting that Nestin+/GFAP+ glial cells may give rise to new neurons. Moreover, following transplantation into aneural colon, brain- and gut-derived NSCs were able to differentiate into neurons. CONCLUSIONS & INFERENCES: Nestin-expressing intestinal NSCs cells give rise to neurospheres, differentiate into neuronal, glial, and mesenchymal lineages in vitro, generate neurons in vivo and can be isolated from mucosa. Further studies are needed for exploring their potential for treating neuropathies.


Assuntos
Sistema Nervoso Entérico/citologia , Mucosa Intestinal/citologia , Células-Tronco Neurais/citologia , Neuroglia/citologia , Neurônios/citologia , Animais , Diferenciação Celular/fisiologia , Embrião de Galinha , Sistema Nervoso Entérico/metabolismo , Imunofluorescência , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Nestina , Células-Tronco Neurais/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Clin Genet ; 83(4): 307-16, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23167617

RESUMO

The enteric nervous system (ENS), the intrinsic innervation of the gastrointestinal tract, is an essential component of the gut neuromusculature and controls many aspects of gut function, including coordinated muscular peristalsis. The ENS is entirely derived from neural crest cells (NCC) which undergo a number of key processes, including extensive migration into and along the gut, proliferation, and differentiation into enteric neurons and glia, during embryogenesis and fetal life. These mechanisms are under the molecular control of numerous signaling pathways, transcription factors, neurotrophic factors and extracellular matrix components. Failure in these processes and consequent abnormal ENS development can result in so-called enteric neuropathies, arguably the best characterized of which is the congenital disorder Hirschsprung disease (HSCR), or aganglionic megacolon. This review focuses on the molecular and genetic factors regulating ENS development from NCC, the clinical genetics of HSCR and its associated syndromes, and recent advances aimed at improving our understanding and treatment of enteric neuropathies.


Assuntos
Sistema Nervoso Entérico/fisiologia , Trato Gastrointestinal/inervação , Neurônios/fisiologia , Animais , Encéfalo/fisiologia , Sistema Nervoso Entérico/crescimento & desenvolvimento , Sistema Nervoso Entérico/metabolismo , Trato Gastrointestinal/crescimento & desenvolvimento , Trato Gastrointestinal/metabolismo , Humanos , Transdução de Sinais/fisiologia
15.
Neurogastroenterol Motil ; 24(12): e611-21, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23106847

RESUMO

BACKGROUND: Noninvasive methods are needed to improve the diagnosis of enteric neuropathies. Full-field optical coherence microscopy (FFOCM) is a novel optical microscopy modality that can acquire 1 µm resolution images of tissue. The objective of this research was to demonstrate FFOCM imaging for the characterization of the enteric nervous system (ENS). METHODS: Normal mice and EdnrB(-/-) mice, a model of Hirschsprung's disease (HD), were imaged in three-dimensions ex vivo using FFOCM through the entire thickness and length of the gut. Quantitative analysis of myenteric ganglia was performed on FFOCM images obtained from whole-mount tissues and compared with immunohistochemistry imaged by confocal microscopy. KEY RESULTS: Full-field optical coherence microscopy enabled visualization of the full thickness gut wall from serosa to mucosa. Images of the myenteric plexus were successfully acquired from the stomach, duodenum, colon, and rectum. Quantification of ganglionic neuronal counts on FFOCM images revealed strong interobserver agreement and identical values to those obtained by immunofluorescence microscopy. In EdnrB(-/-) mice, FFOCM analysis revealed a significant decrease in ganglia density along the colorectum and a significantly lower density of ganglia in all colorectal segments compared with normal mice. CONCLUSIONS & INFERENCES: Full-field optical coherence microscopy enables optical microscopic imaging of the ENS within the bowel wall along the entire intestine. FFOCM is able to differentiate ganglionic from aganglionic colon in a mouse model of HD, and can provide quantitative assessment of ganglionic density. With further refinements that enable bowel wall imaging in vivo, this technology has the potential to revolutionize the characterization of the ENS and the diagnosis of enteric neuropathies.


Assuntos
Sistema Nervoso Entérico , Imageamento Tridimensional/métodos , Microscopia Confocal/métodos , Plexo Mientérico , Tomografia de Coerência Óptica/métodos , Animais , Modelos Animais de Doenças , Feminino , Gânglios Autônomos , Doença de Hirschsprung/patologia , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Adulto Jovem
16.
Neurogastroenterol Motil ; 24(9): 874-e400, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22626027

RESUMO

BACKGROUND: Congenital aganglionosis (Hirschsprung's disease) results in colonic dysmotility and a risk for Hirschsprung's-associated enterocolitis (HAEC), whose cause is unknown. We hypothesized that aganglionosis leads to microbiome changes that may contribute to HAEC risk. METHODS: Colon and fecal samples were collected from endothelin receptor B-null (Ednrb(-/-) ) mice, an established model of colorectal aganglionosis, at postnatal day 7 (P7), P20, and P24. We determined microbiome composition by 16S ribosomal RNA gene pyrosequencing and fecal metabolite profile by nuclear magnetic resonance spectroscopy. KEY RESULTS: Wild-type (WT) mice exhibited increasing species diversity with age, with mutant mice possessing even greater diversity. WT and mutant microbiomes, both fecal and colonic, significantly segregated by principal coordinates analysis based on species composition at all ages examined. Importantly, mutant mice contained more Bacteroidetes and less Firmicutes than WT, with additional genus- and species-level differences observed. Notably, mutant P7 colon was dominated by coagulase-negative Staphylococcus species, which were rare in WT. Mutant fecal metabolite profiles also differed, particularly in the abundance of formate, a short-chain fatty acid product of microbial fermentation. CONCLUSIONS & INFERENCES: Colorectal aganglionosis is associated with early and sustained disruption of the normal colonic and fecal microbiome, supporting the enteric nervous system as a determinant of microbiome composition. Furthermore, the differences observed suggest a potential contributory role for the microbiome in the etiology of HAEC. These findings provide a basis for further studies to determine the causative role of specific bacterial communities in HAEC and the potential to restore the normal microbiome in Hirschsprung's disease.


Assuntos
Colo/microbiologia , Enterocolite/microbiologia , Fezes/química , Doença de Hirschsprung/microbiologia , Metagenoma/fisiologia , RNA Ribossômico 16S/análise , Animais , Bactérias/classificação , Bactérias/genética , Biodiversidade , Modelos Animais de Doenças , Enterocolite/etiologia , Doença de Hirschsprung/complicações , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Transgênicos
17.
Br J Cancer ; 106(1): 206-9, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22095229

RESUMO

BACKGROUND: To determine whether non-viral nasopharyngeal carcinoma (NPC) risk factors might be associated with (and mediated through) Epstein-Barr virus (EBV) serological responses linked to NPC risk, we evaluated predictors of risk of anti-EBNA1 IgA seropositivity and other markers among unaffected relatives from a large NPC family study in Taiwan. METHODS: Multivariate logistic regression conditioned on family was used to examine the associations between sociodemographic, dietary, lifestyle, and occupational variables and risk of anti-EBV EBNA1 IgA positivity, anti-VCA IgA, and anti-DNase positivity. RESULTS: Among 2393 unaffected relatives from 319 multiplex families, 1180 (49.3%) were anti-EBV EBNA1 IgA seropositive. None of the associations with anti-EBNA1 IgA were statistically significant, except for being 31-50 years of age (vs <30, adjusted ORs 0.51-0.57). For one or more EBV serological markers, there were suggestive associations for older age, GuangDong firm salted fish, betel use, current alcohol use, and male gender. CONCLUSION: Overall, we found little evidence to suggest that non-viral NPC risk factors significantly alter EBV serological patterns, suggesting that non-viral NPC risk factors act through pathways independent of EBV serological responses.


Assuntos
Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Imunoglobulina A/sangue , Neoplasias Nasofaríngeas/imunologia , Adolescente , Adulto , Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/patologia
18.
Br J Cancer ; 105(2): 320-6, 2011 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-21654679

RESUMO

BACKGROUND: We conducted the first analysis of viral microRNAs (miRNAs) in lung cancer, with a focus on Epstein-Barr virus (EBV). METHODS: We evaluated viral miRs with a two-channel oligo-array targeting mature, anti-sense miRNAs in 290 cases. In 48 cases, we compared microarray and real-time quantitative PCR (qPCR) expression for three EBV miRNAs. We tested for EBV DNA, RNA, and protein in tumour tissue from six cases with and six cases without strong qPCR-based evidence of EBV miRNAs. RESULTS: The EBV miRNAs strongly differentiated between adenocarcinoma and squamous cell carcinoma using the microarray (P<0.01 for 9 out of 16 EBV miRNAs). However, microarray and qPCR measurements of BART1, BART2, and BHRF1-3 expression were not significantly correlated (P=0.53, 0.94, and 0.47, respectively). Although qPCR provided substantial evidence of EBV miRNAs in 7 out of 48 cases, only 1 of these 7 cases had detectable EBV DNA in tumour tissue. None had detectable EBV RNA or protein by histochemical stains. CONCLUSION: In a comprehensive evaluation of EBV miRNA, DNA, RNA, and protein in lung cancer, we found little evidence of EBV in lung tumour tissue. Discrepancies between microarray- and qPCR-based strategies highlight the difficulty of validating molecular markers of disease. Our results do not support a role of EBV in lung cancer.


Assuntos
Adenocarcinoma/virologia , Carcinoma de Células Escamosas/virologia , Herpesvirus Humano 4/genética , Neoplasias Pulmonares/virologia , MicroRNAs/genética , Adenocarcinoma/complicações , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/genética , Estudos de Casos e Controles , DNA Viral/análise , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 4/fisiologia , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/genética , Masculino , MicroRNAs/análise , MicroRNAs/fisiologia , Análise em Microsséries , Pessoa de Meia-Idade , RNA Viral/análise , Proteínas Virais/análise
19.
J Natl Cancer Inst ; 102(20): 1568-83, 2010 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-20876876

RESUMO

BACKGROUND: Carrying the cyclin-dependent kinase inhibitor 2A (CDKN2A) germline mutations is associated with a high risk for melanoma. Penetrance of CDKN2A mutations is modified by pigmentation characteristics, nevus phenotypes, and some variants of the melanocortin-1 receptor gene (MC1R), which is known to have a role in the pigmentation process. However, investigation of the associations of both MC1R variants and host phenotypes with melanoma risk has been limited. METHODS: We included 815 CDKN2A mutation carriers (473 affected, and 342 unaffected, with melanoma) from 186 families from 15 centers in Europe, North America, and Australia who participated in the Melanoma Genetics Consortium. In this family-based study, we assessed the associations of the four most frequent MC1R variants (V60L, V92M, R151C, and R160W) and the number of variants (1, ≥2 variants), alone or jointly with the host phenotypes (hair color, propensity to sunburn, and number of nevi), with melanoma risk in CDKN2A mutation carriers. These associations were estimated and tested using generalized estimating equations. All statistical tests were two-sided. RESULTS: Carrying any one of the four most frequent MC1R variants (V60L, V92M, R151C, R160W) in CDKN2A mutation carriers was associated with a statistically significantly increased risk for melanoma across all continents (1.24 × 10(-6) ≤ P ≤ .0007). A consistent pattern of increase in melanoma risk was also associated with increase in number of MC1R variants. The risk of melanoma associated with at least two MC1R variants was 2.6-fold higher than the risk associated with only one variant (odds ratio = 5.83 [95% confidence interval = 3.60 to 9.46] vs 2.25 [95% confidence interval = 1.44 to 3.52]; P(trend) = 1.86 × 10(-8)). The joint analysis of MC1R variants and host phenotypes showed statistically significant associations of melanoma risk, together with MC1R variants (.0001 ≤ P ≤ .04), hair color (.006 ≤ P ≤ .06), and number of nevi (6.9 × 10(-6) ≤ P ≤ .02). CONCLUSION: Results show that MC1R variants, hair color, and number of nevi were jointly associated with melanoma risk in CDKN2A mutation carriers. This joint association may have important consequences for risk assessments in familial settings.


Assuntos
Genes p16 , Heterozigoto , Melanoma/genética , Mutação , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Adulto , Austrália , Inibidor p16 de Quinase Dependente de Ciclina/genética , Europa (Continente) , Feminino , Cor de Cabelo , Humanos , Masculino , Nevo/complicações , Nevo/genética , América do Norte , Fenótipo , Medição de Risco , Fatores de Risco , Pigmentação da Pele , Queimadura Solar/complicações , População Branca/genética
20.
Clin Genet ; 77(4): 365-73, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20002457

RESUMO

The effects of DNA repair and transcription gene abnormalities in human pre-natal life have never been studied. Trichothiodystrophy (TTD) is a rare (affected frequency of 10(-6)) recessive disorder caused by mutations in genes involved in nucleotide excision repair (NER) pathway and in transcription. Based on our novel clinical observations, we conducted a genetic epidemiologic study to investigate gestational outcomes associated with TTD. We compared pregnancies resulting in TTD-affected offspring (n = 24) with respect to abnormalities during their antenatal and neonatal periods to pregnancies resulting in their unaffected siblings (n = 18), accounting for correlation, and to population reference values. Significantly higher incidence of several severe gestational complications was noted in TTD-affected pregnancies. Small for gestational age (SGA) <10th percentile [Relative risk (RR ) = 9.3, 95% CI = 1.4-60.5, p = 0.02], SGA <3rd percentile (RR = 7.2, 95% CI = 1.1-48.1, p = 0.04), and neonatal intensive care unit (NICU) hospitalization (RR = 6.4, 95% CI = 1.4-29.5, p = 0.02) occurred more frequently among TTD-affected neonates compared with their unaffected siblings. Compared with reference values from general obstetrical population, pregnancies that resulted in TTD-affected infants were significantly more likely to be complicated by hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome (RR = 35.7, 95% CI = 7.6-92.5, p = 0.0002), elevated mid-trimester maternal serum human chorionic gonadotropin (hCG) levels (RR = 14.3, 95% CI = 7.0-16.6, p < 0.0001), SGA <3rd percentile (RR = 13.9, 95% CI = 7.4-21.1, p < 0.0001), pre-term delivery (<32 weeks) (RR = 12.0, 95% CI = 4.9-21.6, p < 0.0001), pre-eclampsia (RR = 4.0, 95% CI = 1.6-7.4, p = 0.006), and decreased fetal movement (RR = 3.3, 95% CI = 1.6-5.2, p = 0.0018). Abnormal placental development is an underlying mechanism that may explain the constellation of observed complications in our study. Thus, we hypothesize that TTD DNA repair and transcription genes play an important role in normal human placental development.


Assuntos
Reparo do DNA/genética , Desenvolvimento Fetal/genética , Transcrição Gênica , Síndromes de Tricotiodistrofia/embriologia , Síndromes de Tricotiodistrofia/genética , Adulto , Demografia , Família , Feminino , Humanos , Nascido Vivo , Pessoa de Meia-Idade , Gravidez , Resultado da Gravidez , Valores de Referência , Adulto Jovem
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