Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Cancer Cell ; 38(4): 567-583.e11, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-32976774

RESUMO

Oncogenic transformation alters lipid metabolism to sustain tumor growth. We define a mechanism by which cholesterol metabolism controls the development and differentiation of pancreatic ductal adenocarcinoma (PDAC). Disruption of distal cholesterol biosynthesis by conditional inactivation of the rate-limiting enzyme Nsdhl or treatment with cholesterol-lowering statins switches glandular pancreatic carcinomas to a basal (mesenchymal) phenotype in mouse models driven by KrasG12D expression and homozygous Trp53 loss. Consistently, PDACs in patients receiving statins show enhanced mesenchymal features. Mechanistically, statins and NSDHL loss induce SREBP1 activation, which promotes the expression of Tgfb1, enabling epithelial-mesenchymal transition. Evidence from patient samples in this study suggests that activation of transforming growth factor ß signaling and epithelial-mesenchymal transition by cholesterol-lowering statins may promote the basal type of PDAC, conferring poor outcomes in patients.


Assuntos
Vias Biossintéticas/genética , Carcinoma Ductal Pancreático/genética , LDL-Colesterol/biossíntese , Neoplasias Pancreáticas/genética , Fator de Crescimento Transformador beta/genética , 3-Hidroxiesteroide Desidrogenases/genética , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Atorvastatina/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Estimativa de Kaplan-Meier , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Transdução de Sinais/genética , Fator de Crescimento Transformador beta/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
2.
Pediatr Dermatol ; 34(4): 386-391, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28548465

RESUMO

BACKGROUND/OBJECTIVES: Infantile hemangiomas (IHs) are vascular tumors with the potential for significant morbidity. There is a lack of validated objective tools to assess IH severity and response to treatment. Diffuse optical spectroscopy (DOS), a noninvasive, nonionizing imaging modality, can measure total hemoglobin concentration and hemoglobin oxygen saturation in tissue to assess IH vascularity and response to treatment. Our objective was to evaluate the utility of a wireless, handheld DOS system to assess IH characteristics at selected points during their clinical course. METHODS: Thirteen subjects (initial age 5.8 ± 2.0 mos) with 15 IHs were enrolled. IHs were classified as proliferative, plateau phase, or involuting. Nine patients with 11 IHs were untreated; four patients with 4 IHs were treated with timolol or propranolol. Each IH was evaluated by placing the DOS system directly on the lesion as well a normal contralateral skin site. IH vascularity and oxygenation were scored using a newly defined normalized hypoxia fraction (NHF) coefficient. Measurements were recorded at various intervals from the initial visit to 1 to 2 years of age. RESULTS: For the nine untreated IHs, the NHF was highest at 6 months of age, during proliferation. Differences in NHFs between the proliferation and the plateau (p = 0.02) and involuting (p < 0.001) stages were statistically significant. In treated patients, the NHF normalized to 60% after 2 months. One treated IH came within 5% of the NHF for normal skin after 12 months. CONCLUSIONS: DOS can be used to assess the vascularity and tissue oxygenation of IHs and monitor their progression and response to treatment.


Assuntos
Hemangioma/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Antagonistas Adrenérgicos beta/uso terapêutico , Criança , Pré-Escolar , Feminino , Hemangioma/tratamento farmacológico , Humanos , Lactente , Estudos Longitudinais , Projetos Piloto , Tecnologia sem Fio
3.
Semin Cutan Med Surg ; 35(3): 170-6, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27607326

RESUMO

Vascular anomalies are very common in children and encompass a wide spectrum of diseases. Many vascular anomalies can be mistaken for infantile hemangioma (IH). In addition, there is a variety of rare disorders including benign and malignant tumors that may mimic IH and other types of vascular anomalies. Understanding the clinical features, natural history, and typical clinical course of different types of vascular anomalies is essential in order to make the correct diagnosis and guide management. Radiologic imaging plays an important role in establishing the diagnosis; and when the diagnosis remains in doubt, a biopsy performed by a surgical specialist with expertise may prove to be lifesaving.


Assuntos
Hemangioma/diagnóstico , Dermatopatias/diagnóstico , Neoplasias Cutâneas/diagnóstico , Malformações Vasculares/diagnóstico , Neoplasias Vasculares/diagnóstico , Diagnóstico Diferencial , Hemangioma/congênito , Humanos , Lactente , Dermatopatias/classificação , Neoplasias Cutâneas/congênito , Malformações Vasculares/classificação , Neoplasias Vasculares/classificação
6.
Pediatr Dermatol ; 32(1): 76-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25040287

RESUMO

Capillary malformation-arteriovenous malformation syndrome (CM-AVM) is an autosomal dominant disorder caused by RASA1 mutations. The prevalence and phenotypic spectrum are unknown. Evaluation of patients with multiple CMs is challenging because associated AVMs can be life threatening. The objective of this study was to describe the clinical characteristics of children presenting with features of CM-AVM to an academic pediatric dermatology practice. After institutional review board approval was received, a retrospective chart review was performed of patients presenting between 2009 and 2012 with features of CM-AVM. We report nine cases. Presenting symptoms ranged from extensive vascular stains and cardiac failure to CMs noted incidentally during routine skin examination. All demonstrated multiple CMs, two had Parkes Weber syndrome, and two had multiple infantile hemangiomas. Seven patients had family histories of multiple CMs; three had family histories of large, atypical CMs. Six had personal or family histories of AVMs. Genetic evaluation was recommended for all and was pursued by six families; four RASA1 mutations were identified, including one de novo. Consultations with neurology, cardiology, and orthopedics were recommended. Most patients (89%) have not required treatment to date. CM-AVM is an underrecognized condition with a wide clinical spectrum that often presents in childhood. Further evaluation may be indicated in patients with multiple CMs. This study is limited by its small and retrospective nature.


Assuntos
Malformações Arteriovenosas/diagnóstico , Capilares/anormalidades , Mancha Vinho do Porto/diagnóstico , Malformações Arteriovenosas/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mutação/genética , Mancha Vinho do Porto/genética , Estudos Retrospectivos , Proteína p120 Ativadora de GTPase/genética
7.
J Am Acad Dermatol ; 71(3): 542-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24929885

RESUMO

BACKGROUND: Infantile hemangiomas (IH) on the extremities have not been systematically studied. OBJECTIVE: We sought to describe the clinical characteristics and distribution patterns of IH affecting acral surfaces and to explore the relationship among these patterns, limb development, and IH pathogenesis. METHODS: This was a retrospective multicenter cohort study. Photographic archives from 4 tertiary pediatric dermatology referral centers were searched for patients with IH larger than 1 cm and involving 1 or more digit. Hemangioma location, distribution, and morphologic subtype were recorded. Medical records were reviewed for demographic and clinical data. RESULTS: In all, 73 patients were identified. The most common IH pattern resembled that of a "biker glove" (73%), followed by localized IH on the distal digits (14%), segmental IH extending over the distal digits (8%), and intermediate patterns (5%). Overall, 63% of acral IH were segmental, 26% indeterminate, and 11% localized. Five patients had associated structural anomalies. Complications were noted in 33% of cases. LIMITATIONS: Limitations were retrospective study design; selection bias based on recall and photography; documentation and follow-up were not standardized across institutions; and treatment information may not reflect current approaches. CONCLUSION: Acral IH display specific patterns and are associated with a relatively high risk of ulceration.


Assuntos
Hemangioma/patologia , Feminino , , Mãos , Hemangioma/complicações , Hemangioma/congênito , Hemangioma/epidemiologia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Viés de Seleção , Úlcera Cutânea/complicações
8.
Pediatr Dermatol ; 30(6): e180-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23025620

RESUMO

We present a case of a large congenital hemangioma (CH) on the neck causing cardiac failure and thrombocytopenia in a female neonate. A trial of medical therapy with corticosteroids and propranolol was attempted, but the patient ultimately underwent definitive treatment with embolization and surgical resection with a positive outcome. A review of the English language literature revealed 16 previously reported cases of CHs complicated by congestive heart failure. This series supports known demographic features of CHs, including a lack of gender discrepancy and a predilection to affect the head and neck. These CHs are rarely diagnosed in utero; most patients present with a mass at birth. Cardiac failure is identified prenatally or in the first days of life. A mild to moderate thrombocytopenia and coagulopathy, which is likely transient and distinct from classic Kasabach-Merritt phenomenon, accompanies many of these cases. There is a 30% associated mortality rate. Both medical and interventional treatment modalities have been reported. Steroids are the most commonly used medication, but without any clear benefit. We hypothesize that, based on its possible mechanisms of action,propranolol may be a more effective treatment for CHs requiring treatment. As surgical intervention may be necessary, we recommend a multidisciplinary approach to treating patients with problematic CHs.


Assuntos
Insuficiência Cardíaca/etiologia , Hemangioma/congênito , Hemangioma/complicações , Neoplasias Cutâneas/congênito , Neoplasias Cutâneas/complicações , Cardiomegalia/etiologia , Feminino , Doenças Fetais/patologia , Hemangioma/cirurgia , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Neoplasias Cutâneas/cirurgia
9.
Pediatr Dermatol ; 30(6): e278-80, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22471786

RESUMO

Hermansky-Pudlak syndrome (HPS) is a rare autosomal-recessive disorder characterized by oculocutaneous albinism, a hemorrhagic diathesis due to platelet dysfunction, and lysosomal ceroid accumulation that can cause a Crohn's-like granulomatous colitis and pulmonary fibrosis. We report peristomal and vulvar cutaneous involvement of the granulomatous colitis in HPS.


Assuntos
Doença de Crohn/etiologia , Doença de Crohn/patologia , Síndrome de Hermanski-Pudlak/complicações , Síndrome de Hermanski-Pudlak/patologia , Úlcera Cutânea/etiologia , Úlcera Cutânea/patologia , Biópsia , Criança , Feminino , Humanos , Pele/patologia , Vulva/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA