RESUMO
Hyperargininemia in patients with arginase 1 deficiency (ARG1-D) is considered a key driver of disease manifestations, including spasticity, developmental delay, and seizures. Pegzilarginase (AEB1102) is an investigational enzyme therapy which is being developed as a novel arginine lowering approach. We report the safety and efficacy of intravenously (IV) administered pegzilarginase in pediatric and adult ARG1-D patients (n = 16) from a Phase 1/2 study (101A) and the first 12 weeks of an open-label extension study (102A). Substantial disease burden at baseline included lower-limb spasticity, developmental delay, and previous hyperammonemic episodes in 75%, 56%, and 44% of patients, respectively. Baseline plasma arginine (pArg) was elevated (median 389 µM, range 238-566) on standard disease management. Once weekly repeat dosing resulted in a median decrease of pArg of 277 µM after 20 cumulative doses (n = 14) with pArg in the normal range (40 to 115 µM) in 50% of patients at 168 hours post dose (mean pegzilarginase dose 0.10 mg/kg). Lowering pArg was accompanied by improvements in one or more key mobility assessments (6MWT, GMFM-D & E) in 79% of patients. In 101A, seven hypersensitivity reactions occurred in four patients (out of 162 infusions administered). Other common treatment-related adverse events (AEs) included vomiting, hyperammonemia, pruritus, and abdominal pain. Treatment-related serious AEs that occurred in five patients were all observed in 101A. Pegzilarginase was effective in lowering pArg levels with an accompanying clinical response in patients with ARG1-D. The improvements with pegzilarginase occurred in patients receiving standard treatment approaches, which suggests that pegzilarginase could offer benefit over existing disease management.
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Arginase/genética , Arginase/uso terapêutico , Arginina/sangue , Hiperargininemia/tratamento farmacológico , Adolescente , Adulto , Arginase/efeitos adversos , Arginase/sangue , Arginina/metabolismo , Criança , Pré-Escolar , Gerenciamento Clínico , Feminino , Humanos , Hiperamonemia/etiologia , Hiperargininemia/sangue , Hiperargininemia/genética , Hiperargininemia/metabolismo , Masculino , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Estados Unidos , Vômito/etiologia , Adulto JovemRESUMO
BACKGROUND: Lysosomal acid lipase is an essential lipid-metabolizing enzyme that breaks down endocytosed lipid particles and regulates lipid metabolism. We conducted a phase 3 trial of enzyme-replacement therapy in children and adults with lysosomal acid lipase deficiency, an underappreciated cause of cirrhosis and severe dyslipidemia. METHODS: In this multicenter, randomized, double-blind, placebo-controlled study involving 66 patients, we evaluated the safety and effectiveness of enzyme-replacement therapy with sebelipase alfa (administered intravenously at a dose of 1 mg per kilogram of body weight every other week); the placebo-controlled phase of the study was 20 weeks long and was followed by open-label treatment for all patients. The primary end point was normalization of the alanine aminotransferase level. Secondary end points included additional disease-related efficacy assessments, safety, and side-effect profile. RESULTS: Substantial disease burden at baseline included a very high level of low-density lipoprotein cholesterol (≥190 mg per deciliter) in 38 of 66 patients (58%) and cirrhosis in 10 of 32 patients (31%) who underwent biopsy. A total of 65 of the 66 patients who underwent randomization completed the double-blind portion of the trial and continued with open-label treatment. At 20 weeks, the alanine aminotransferase level was normal in 11 of 36 patients (31%) in the sebelipase alfa group and in 2 of 30 (7%) in the placebo group (P=0.03), with mean changes from baseline of -58 U per liter versus -7 U per liter (P<0.001). With respect to prespecified key secondary efficacy end points, we observed improvements in lipid levels and reduction in hepatic fat content (P<0.001 for all comparisons, except P=0.04 for triglycerides). The number of patients with adverse events was similar in the two groups; most events were mild and were considered by the investigator to be unrelated to treatment. CONCLUSIONS: Sebelipase alfa therapy resulted in a reduction in multiple disease-related hepatic and lipid abnormalities in children and adults with lysosomal acid lipase deficiency. (Funded by Synageva BioPharma and others; ARISE ClinicalTrials.gov number, NCT01757184.).
Assuntos
Esterol Esterase/uso terapêutico , Doença de Wolman/tratamento farmacológico , Adolescente , Adulto , Idoso , Alanina Transaminase/sangue , Biópsia , Criança , Pré-Escolar , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Método Duplo-Cego , Dislipidemias/tratamento farmacológico , Dislipidemias/genética , Feminino , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Esterol Esterase/efeitos adversos , Esterol Esterase/farmacologia , Doença de Wolman/sangue , Adulto Jovem , Doença de WolmanRESUMO
INTRODUCTION: Early diagnosis and treatment of thyroid eye disease (TED) improves outcomes. Previous studies have highlighted delays in diagnosis and referral to specialist centres. The Amsterdam declaration (2009) aimed to halve the time from presentation to diagnosis and from diagnosis to referral to a specialist centre in five years. A recent study from the European group on Graves' orbitopathy tertiary centres showed a trend for earlier referral of patients to the centres. It is unknown whether similar improvements are occurring in secondary care hospitals in the UK. AIM: To study the trend in referral to a UK secondary care specialist TED clinic since the Amsterdam declaration. METHODS: We carried out a prospective audit of patients who attended the specialist TED clinic after the Amsterdam declaration (2010-2015). We compared their clinical characteristics, including duration of symptoms, disease activity and severity, with those of the patients (n = 114) from an earlier audit attending the clinic during 2004-2008. RESULTS: During 2010-2015, 126 patients with TED (97 females, median age 55 years, 39 current smokers) attended the clinic. The median time from onset of symptoms to being seen in the clinic was 5 months, reduced from 12 months in 2004-2008 (p < 0.001). As compared to the 2004-2008 cohort, significantly more patients in the current cohort presented with mild disease (72 vs. 52%, p = 0.002). Twenty-seven per cent patients had active TED (clinical activity score ≥3/7) compared to 18% in 2004-2008 (p = 0.1). CONCLUSIONS: The trend in referral to secondary care specialist TED clinic is changing in line with the Amsterdam declaration aims.
Assuntos
Auditoria Clínica , Prestação Integrada de Cuidados de Saúde/organização & administração , Oftalmopatia de Graves/terapia , Avaliação de Resultados em Cuidados de Saúde , Encaminhamento e Consulta/tendências , Centros de Cuidados de Saúde Secundários , Atenção Secundária à Saúde , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sociedades Médicas , Fatores de Tempo , Reino Unido , Recursos HumanosRESUMO
PURPOSE: The purpose of this study was to enhance understanding of lysosomal acid lipase deficiency (LALD) in infancy. METHODS: Investigators reviewed medical records of infants with LALD and summarized data for the overall population and for patients with and without early growth failure (GF). Kaplan-Meier survival analyses were conducted for the overall population and for treated and untreated patients. RESULTS: Records for 35 patients, 26 with early GF, were analyzed. Prominent symptom manifestations included vomiting, diarrhea, and steatorrhea. Median age at death was 3.7 months; estimated probability of survival past age 12 months was 0.114 (95% confidence interval (CI): 0.009-0.220). Among patients with early GF, median age at death was 3.5 months; estimated probability of survival past age 12 months was 0.038 (95% CI: 0.000-0.112). Treated patients (hematopoietic stem cell transplant (HSCT), n = 9; HSCT and liver transplant, n = 1) in the overall population and the early GF subset survived longer than untreated patients, but survival was still poor (median age at death, 8.6 months). CONCLUSIONS: These data confirm and expand earlier insights on the progression and course of LALD presenting in infancy. Despite variations in the nature, onset, and severity of clinical manifestations, and treatment attempts, clinical outcome was poor.Genet Med 18 5, 452-458.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Esterol Esterase/genética , Doença de Wolman/genética , Doença de Wolman/terapia , Progressão da Doença , Feminino , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Resultado do Tratamento , Doença de Wolman/mortalidade , Doença de Wolman/patologia , Doença de WolmanRESUMO
OBJECTIVE: The aim of this study was to characterize key clinical manifestations of lysosomal acid lipase deficiency (LAL D) in children and adults. METHODS: Investigators reviewed medical records of LAL D patients ages ≥5 years, extracted historical data, and obtained prospective laboratory and imaging data on living patients to develop a longitudinal dataset. RESULTS: A total of 49 patients were enrolled; 48 had confirmed LAL D. Mean age at first disease-related abnormality was 9.0 years (range 0-42); mean age at diagnosis was 15.2 years (range 1-46). Twenty-nine (60%) were male patients, and 27 (56%) were <20 years of age at the time of consent/assent. Serum transaminases were elevated in most patients with 458 of 499 (92%) of alanine aminotransferase values and 265 of 448 (59%) of aspartate aminotransferase values above the upper limit of normal. Most patients had elevated low-density lipoprotein (64% patients) and total cholesterol (63%) at baseline despite most being on lipid-lowering therapies, and 44% had high-density lipoprotein levels below the lower limit of normal. More than half of the patients with liver biopsies (nâ=â31, mean age 13 years) had documented evidence of steatosis (87%) and/or fibrosis (52%). Imaging assessments revealed that the median liver volume was â¼1.15 multiples of normal (MN) and median spleen volume was â¼2.2 MN. Six (13%) patients had undergone a liver transplant (ages 9-43.5 years). CONCLUSION: This study provides the largest longitudinal case review of patients with LAL D and confirms that LAL D is predominantly a pediatric disease causing early and progressive hepatic dysfunction associated with dyslipidemia that often leads to liver failure and transplantation.
Assuntos
Doença do Armazenamento de Colesterol Éster , Colesterol/sangue , Fígado Gorduroso/etiologia , Fígado , Esterol Esterase/deficiência , Doença de Wolman , Adolescente , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Criança , Pré-Escolar , Doença do Armazenamento de Colesterol Éster/sangue , Doença do Armazenamento de Colesterol Éster/patologia , Fígado Gorduroso/sangue , Feminino , Humanos , Lipase/deficiência , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/etiologia , Transplante de Fígado , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Baço/patologia , Doença de Wolman/sangue , Doença de Wolman/patologia , Adulto Jovem , Doença de WolmanRESUMO
BACKGROUND & AIMS: Lysosomal acid lipase deficiency is an autosomal recessive enzyme deficiency resulting in lysosomal accumulation of cholesteryl esters and triglycerides. LAL-CL04, an ongoing extension study, investigates the long-term effects of sebelipase alfa, a recombinant human lysosomal acid lipase. METHODS: Sebelipase alfa (1mg/kg or 3mg/kg) was infused every-other-week to eligible subjects. Safety and tolerability assessments, including liver function, lipid profiles and liver volume assessment, were carried out at regular intervals. RESULTS: 216 infusions were administered to eight adult subjects through week 52 during LAL-CL04. At week 52, mean alanine aminotransferase and aspartate aminotransferase levels were normal with mean change from baseline of -58% and -40%. Mean changes for low-density lipoprotein, total cholesterol, triglyceride and high-density lipoprotein were -60%, -39%, -36%, and +29%, respectively. Mean liver volume by magnetic resonance imaging and hepatic proton density fat fraction decreased (12% and 55%, respectively). Adverse events were mainly mild and unrelated to sebelipase alfa. Infusion-related reactions were uncommon: three events of moderate severity were reported in two subjects; one patient's event was suggestive of a hypersensitivity-like reaction, but additional testing did not confirm this, and the subject has successfully re-started sebelipase alfa. Of samples tested to date, no anti-drug antibodies have been detected. CONCLUSIONS: Long-term dosing with sebelipase alfa in lysosomal acid lipase-deficient patients is well tolerated and produces sustained reductions in transaminases, improvements in serum lipid profile and reduction in the hepatic fat fraction. A randomized, placebo-controlled phase 3 trial in children and adults is underway (ARISE: NCT01757184).
Assuntos
Esterol Esterase/administração & dosagem , Doença de Wolman/tratamento farmacológico , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Esquema de Medicação , Feminino , Humanos , Lipídeos/sangue , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Esterol Esterase/efeitos adversos , Esterol Esterase/deficiência , Doença de Wolman/sangue , Doença de Wolman/patologia , Adulto JovemRESUMO
UNLABELLED: Cholesteryl ester storage disease (CESD), an inherited deficiency of lysosomal acid lipase (LAL), is an underappreciated cause of progressive liver disease with no approved therapy. Presenting features include dyslipidemia, elevated transaminases, and hepatomegaly. To assess the clinical effects and safety of the recombinant human LAL, sebelipase alfa, nine patients received four once-weekly infusions (0.35, 1, or 3 mg·kg(-1) ) in LAL-CL01, which is the first human study of this investigational agent. Patients completing LAL-CL01 were eligible to enroll in the extension study (LAL-CL04) in which they again received four once-weekly infusions of sebelipase alfa (0.35, 1, or 3 mg·kg(-1) ) before transitioning to long-term every-other-week infusions (1 or 3 mg·kg(-1) ). Sebelipase alfa was well tolerated, with mostly mild adverse events unrelated to sebelipase alfa. No antidrug antibodies were detected. Transaminases decreased in patients in LAL-CL01 and increased between studies. In seven patients receiving ongoing sebelipase alfa treatment in LAL-CL04, the mean ± standard deviation (SD) decreases for alanine transaminase and aspartate aminotransferase at week 12 compared to the baseline values in LAL-CL01 were 46 ± 21 U/L (-52%) and 21 ± 14 U/L (-36%), respectively (P ≤ 0.05). Through week 12 of LAL-CL04, these seven patients also showed mean decreases from baseline in total cholesterol of 44 ± 41 mg/dL (-22%; P = 0.047), low density lipoprotein-cholesterol of 29 ± 31 mg/dL (-27%; P = 0.078), and triglycerides of 50 ± 38 mg/dL (-28%, P = 0.016) and increases in high density lipoprotein-cholesterol of 5 mg/dL (15%; P = 0.016). CONCLUSION: These data establish that sebelipase alfa, an investigational enzyme replacement, in patients with CESD is well tolerated, rapidly decreases serum transaminases, and that these improvements are sustained with long-term dosing and are accompanied by improvements in serum lipid profile.
Assuntos
Doença do Armazenamento de Colesterol Éster/tratamento farmacológico , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Esterol Esterase/efeitos adversos , Esterol Esterase/uso terapêutico , Adulto , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Doença do Armazenamento de Colesterol Éster/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Relação Dose-Resposta a Droga , Feminino , Humanos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/farmacocinética , Esterol Esterase/farmacocinética , Resultado do Tratamento , Triglicerídeos/sangueRESUMO
BACKGROUND & AIMS: Lysosomal Acid Lipase (LAL) deficiency is a rare metabolic storage disease, caused by a marked reduction in activity of LAL, which leads to accumulation of cholesteryl esters (CE) and triglycerides (TG) in lysosomes in many tissues. We used (1)H magnetic resonance (MR) spectroscopy to characterize the abnormalities in hepatic lipid content and composition in patients with LAL deficiency, and in ex vivo liver tissue from a LAL deficiency rat model. Secondly, we used MR spectroscopy to monitor the effects of an enzyme replacement therapy (ERT), sebelipase alfa (a recombinant human lysosomal acid lipase), on hepatic TG and CE content in the preclinical model. METHODS: Human studies employed cohorts of LAL-deficient patients and NAFLD subjects. Rat experimental groups comprised ex vivo liver samples of wild type, NAFLD, LAL-deficient, and LAL-deficient rats receiving 4weeks of sebelipase alfa treatment. Hepatic (1)H MR spectroscopy was performed using 3T (human) and 7T (preclinical) MRI scanners to quantify hepatic cholesterol and triglyceride content. RESULTS: CE accumulation was identified in LAL deficiency in both human and preclinical studies. A significant decrease in hepatic CE was observed in LAL-deficient rats following treatment with sebelipase alfa. CONCLUSIONS: We demonstrate an entirely non-invasive method to identify and quantify the hepatic lipid signature associated with a rare genetic cause of fatty liver. The approach provides a more favorable alternative to repeated biopsy sampling for diagnosis and disease progression / treatment monitoring of patients with LAL deficiency and other disorders characterised by increased free cholesterol and/or cholesteryl esters.
Assuntos
Ésteres do Colesterol/metabolismo , Fígado/metabolismo , Esterol Esterase/deficiência , Doença de Wolman/metabolismo , Animais , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Fígado Gorduroso/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Hepatopatia Gordurosa não Alcoólica , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Proteínas Recombinantes/uso terapêutico , Esterol Esterase/genética , Esterol Esterase/uso terapêutico , Triglicerídeos/metabolismo , Doença de Wolman/tratamento farmacológico , Doença de Wolman/genética , Doença de WolmanRESUMO
This is the first report of a supplemented CF patient presenting with clinical vitamin A deficiency to be successfully treated with zinc therapy alone. Therefore in addition to retinol supplementation, normalizing serum zinc levels may be important in maintaining the vitamin A status of CF patients. The interactions and synergistic effects between the two micronutrients are discussed.
Assuntos
Cegueira Noturna/tratamento farmacológico , Oligoelementos/uso terapêutico , Sulfato de Zinco/uso terapêutico , Zinco/deficiência , Fibrose Cística/complicações , Suplementos Nutricionais , Feminino , Humanos , Cegueira Noturna/diagnóstico , Cegueira Noturna/etiologia , Adulto JovemRESUMO
Uveitis in children is associated with several sight-threatening ocular complications, including the formation of cataracts. The surgical management of uveitic cataracts in children is both challenging and controversial and, unlike in adult uveitic cataracts, surgery has historically been associated with poor visual outcomes. Juvenile idiopathic arthritis-associated uveitis in particular poses unique therapeutic challenges and the issue of correction of aphakia in these patients remains a contentious one. The growing use of immunotherapies and, where needed, targeted biologic agents in childhood uveitis increases our potential to implant lenses and predict outcomes. The authors review the available evidence base for the treatment of these children.
Assuntos
Extração de Catarata , Catarata/etiologia , Uveíte/complicações , Artrite Juvenil/complicações , Criança , Pré-Escolar , Humanos , Lactente , Implante de Lente Intraocular , Resultado do TratamentoRESUMO
Bohring-Opitz syndrome is a rare genetic condition of uncertain inheritance. It was first delineated by Bohring and coworkers in 1999 and up to 15 possible cases have been reported. It has both ophthalmic and systemic features and represents a unique syndrome considered to be distinct from Opitz C trigonocephaly syndrome. The classic features of Bohring-Opitz syndrome include prominent metopic suture, exophthalmos, hypertelorism, cleft lip and palate, flexion deformities of the upper limbs, nevi flammei, and significant neurodevelopmental delay. We report a child with Bohring-Opitz syndrome and infantile high myopia. Bohring's original description of the phenotype did not include myopia but since then both this case and two others have reported this association. The presence of high myopia may be helpful in identifying suitable candidate genes and elucidating the genetic mechanism, as well as alerting ophthalmologists to the importance of refraction for affected children.
Assuntos
Anormalidades Múltiplas/genética , Miopia/genética , Refração Ocular , Anormalidades Múltiplas/diagnóstico , Fenda Labial/diagnóstico , Fenda Labial/genética , Fissura Palatina/diagnóstico , Fissura Palatina/genética , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/genética , Progressão da Doença , Exoftalmia/diagnóstico , Exoftalmia/genética , Feminino , Seguimentos , Testa/anormalidades , Humanos , Hipertelorismo/diagnóstico , Hipertelorismo/genética , Recém-Nascido , Miopia/diagnóstico , Síndrome , Fatores de TempoRESUMO
BACKGROUND: Infants presenting with lysosomal acid lipase deficiency have marked failure to thrive, diarrhea, massive hepatosplenomegaly, anemia, rapidly progressive liver disease, and death typically in the first 6 months of life; the only available potential treatment has been hematopoietic stem cell transplantation, which is associated with high morbidity and mortality in this population. The study objective was to evaluate safety and efficacy (including survival) of enzyme replacement with sebelipase alfa in infants with lysosomal acid lipase deficiency. This is an ongoing multicenter, open-label, phase 2/3 study conducted in nine countries. The study enrolled infants with growth failure prior to 6 months of age with rapidly progressive lysosomal acid lipase deficiency; they received once-weekly doses of sebelipase alfa initiated at 0.35 mg/kg with intrapatient dose escalation up to 5 mg/kg. The main outcome of interest is survival to 12 months and survival beyond 24 months of age. RESULTS: Nine patients were enrolled; median age at baseline was 3.0 months (range 1.1-5.8 months). Sixty-seven percent (exact 95% CI 30%-93%) of sebelipase alfa-treated infants survived to 12 months of age compared with 0% (exact 95% CI 0%-16%) for a historical control group (n = 21). Patients who survived to age 12 months exhibited improvements in weight-for-age, reductions in markers of liver dysfunction and hepatosplenomegaly, and improvements in anemia and gastrointestinal symptoms. Three deaths occurred early (first few months of life), two patients died because of advanced disease, and a third patient died following complications of non-protocol-specified abdominal paracentesis. A fourth death occurred at 15 months of age and was related to other clinical conditions. The five surviving patients have survived to age ≥24 months with continued sebelipase alfa treatment; all have displayed marked improvement in growth parameters and liver function. Serious adverse events considered related to sebelipase alfa were reported in one of the nine infants (infusion reaction: tachycardia, pallor, chills, and pyrexia). Most infusion-associated reactions were mild and non-serious. CONCLUSION: Sebelipase alfa markedly improved survival with substantial clinically meaningful improvements in growth and other key disease manifestations in infants with rapidly progressive lysosomal acid lipase deficiency TRIAL REGISTRATION: Clinicaltrials.gov NCT01371825 . Registered 9 June 2011.
Assuntos
Esterol Esterase/uso terapêutico , Doença de Wolman/tratamento farmacológico , Feminino , Humanos , Lactente , Masculino , Análise de Sobrevida , Doença de Wolman/mortalidade , Doença de WolmanRESUMO
Activation of the Sonic hedgehog signaling pathway, primarily through mutational inactivation of the PTCH1 gene, is associated with the development of basal cell carcinoma (BCC). Gli1, a member of the Gli family of transcription factors, is expressed in BCC and in transgenic mice targeted expression of Gli1 in basal keratinocytes leads to BCC development. In addition to BCC, previous studies have shown that Gli1 is expressed in the outer root sheath (ORS) of the hair follicle but is absent in interfollicular epidermis. In this study, we have characterized the expression pattern of two protein kinase C (PKC) isoforms expressed in BCC and hair follicles. We have then used reporter assays to investigate the effects of these isoforms on Gli1 transcriptional activity. We report that in BCC sections, PKCalpha but not PKCdelta was weakly expressed in the epidermis, whereas in the hair follicle, PKCalpha was expressed in the ORS and PKCdelta in the inner root sheath. In contrast, neither PKCalpha nor PKCdelta was expressed in BCC tumor islands, although both isoforms were often expressed in the surrounding stroma. In mammalian 293T cells, coexpression of constitutively active PKCalpha reduced the activity of Gli1 in a dose-dependent manner, whereas constitutively active PKCdelta increased the activity of Gli1, although this required higher expression levels. Regulation of mutant Gli1 protein localized exclusively to the nucleus was similar to that of the wild-type protein, indicating that nuclear-cytoplasmic shuttling is not a determinant of Gli1 control by either PKC isoform. Furthermore, PKC regulation of Gli1 did not involve activation of mitogen-activated protein kinase signaling. Finally, we show that exogenous Gli1 does not alter the expression of PKCalpha in human primary keratinocytes, suggesting that loss of this isoform in BCC is not via Hedgehog signaling. As BCCs have been proposed to originate from the ORS, loss of PKCalpha expression may be relevant to tumor formation; this may, in part, be because of the predicted increase in Gli1 transcriptional activity.
Assuntos
Carcinoma Basocelular/enzimologia , Proteínas Quinases Dependentes de AMP Cíclico/biossíntese , Isoenzimas/biossíntese , Proteínas Oncogênicas/genética , Neoplasias Cutâneas/enzimologia , Fatores de Transcrição/genética , Carcinoma Basocelular/genética , Carcinoma Basocelular/patologia , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Folículo Piloso , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Isoenzimas/fisiologia , Queratinócitos/enzimologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Transativadores , Ativação Transcricional , Proteína GLI1 em Dedos de ZincoRESUMO
Forkhead box (FOX) proteins have been shown to play important roles in regulating the expression of genes involved in cell growth, proliferation, differentiation, longevity, and transformation. The functional importance of this gene family in normal human skin physiology and disease processes is not well understood. Activation of Sonic Hedgehog (Shh) signaling plays a key role in the development of basal cell carcinomas (BCCs) of the skin in humans. Recent studies have established that some FOX genes are downstream targets of Shh signaling. We have investigated the role of FOX proteins in transducing Shh effects in human skin by using degenerate PCR to identify FOX genes differentially expressed in BCCs. All three known FOXM1 isoforms (a, b, and c) were detected in human skin and cultured keratinocytes, and the transcriptionally active FOXM1b isoform was found to be up-regulated in BCCs. Real-time quantitative RT-PCR showed that the increase in FOXM1 mRNA levels was specific for BCCs and not a reflection of increased cell proliferation in that no up-regulation was seen in squamous cell carcinomas or proliferating primary human keratinocyte cultures. Immunostaining studies showed intense nuclear and cytoplasmic staining throughout BCC tumor islands and not confined to the periphery regions of the tumor where proliferating Ki-67-immunopositive cells are predominantly localized. Expression of the Shh target glioma transcription factor-1 (Gli1) in primary keratinocytes and other cell lines caused a significant elevation of FOXM1 mRNA level and transcriptional activity, indicating that FOXM1 is a downstream target of Gli1. Our data provide the first evidence that activation of Shh signaling via Gli1 is an important determinant of FOXM1 expression in mammalian cells. Given the role of FOXM1 in cell proliferation, the up-regulation of FOXM1 in BCCs may be one of the mechanisms whereby Shh signaling exerts its mitogenic effect on basal keratinocytes, leading to the development of this common human cancer.
Assuntos
Carcinoma Basocelular/metabolismo , Neoplasias Cutâneas/metabolismo , Fatores de Transcrição/fisiologia , Animais , Carcinoma Basocelular/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead , Regulação Neoplásica da Expressão Gênica , Proteínas Hedgehog , Humanos , Fatores de Transcrição Kruppel-Like , Camundongos , Camundongos Endogâmicos C3H , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Transdução de Sinais/fisiologia , Pele/metabolismo , Neoplasias Cutâneas/genética , Transativadores/fisiologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Proteína GLI1 em Dedos de ZincoRESUMO
Transgenic mouse models have provided evidence that activation of the zinc-finger transcription factor GLI1 by Hedgehog (Hh)-signalling is a key step in the initiation of the tumorigenic programme leading to Basal Cell Carcinoma (BCC). However, the downstream events underlying Hh/GLI-induced BCC development are still obscure. Using in vitro model systems to analyse the effect of Hh/GLI-signalling in human keratinocytes, we identified a positive feedback mechanism involving the zinc finger transcription factors GLI1 and GLI2. Expression of GLI1 in human keratinocytes induced the transcriptional activator isoforms GLI2alpha and GLI2beta. Both isoforms were also shown to be expressed at elevated levels in 21 BCCs compared to normal skin. Detailed time course experiments monitoring the transcriptional response of keratinocytes either to GLI1 or to GLI2 suggest that GLI1 is a direct target of GLI2, while activation of GLI2 by GLI1 is likely to be indirect. Furthermore, expression of either GLI2 or GLI1 led to an increase in DNA-synthesis in confluent human keratinocytes. Taken together, these results suggest an important role of the positive GLI1-GLI2 feedback loop in Hh-mediated epidermal cell proliferation.
Assuntos
Carcinoma Basocelular/metabolismo , Retroalimentação Fisiológica/fisiologia , Proteínas Oncogênicas/fisiologia , Neoplasias Cutâneas/metabolismo , Fatores de Transcrição/fisiologia , Fosfatase Alcalina/metabolismo , Western Blotting , Bromodesoxiuridina , Carcinoma Basocelular/genética , Primers do DNA/química , DNA de Neoplasias/biossíntese , Ativação Enzimática , Citometria de Fluxo , Proteínas de Fluorescência Verde , Proteínas Hedgehog , Humanos , Queratinócitos/metabolismo , Fatores de Transcrição Kruppel-Like , Luciferases/metabolismo , Proteínas Luminescentes/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Nucleares , Receptores Patched , Reação em Cadeia da Polimerase , RNA/metabolismo , Receptores de Superfície Celular , Retroviridae/genética , Transdução de Sinais , Neoplasias Cutâneas/genética , Transativadores/fisiologia , Transcrição Gênica , Transfecção , Proteína GLI1 em Dedos de Zinco , Proteína Gli2 com Dedos de Zinco , Dedos de ZincoRESUMO
In stratified epidermis, activation of the Hh/Gli signal transduction pathway has been implicated in the control of cell proliferation and tumorigenesis. The zinc-finger transcription factor Gli2 has been identified as critical mediator of the Hh signal at the distal end of the pathway, but the molecular mechanisms by which Gli2 regulates cell proliferation or induces epidermal malignancies such as basal cell carcinoma are still unclear. Here, we provide evidence for a role of human GLI2 in antagonizing contact inhibition and epidermal differentiation. We show by gene expression profiling that activation of the GLI2 oncogene in human keratinocytes activates the transcription of a number of genes involved in cell cycle progression such as E2F1, CCND1, CDC2 and CDC45L, while it represses genes associated with epidermal differentiation. Analysis of the proliferative effect of GLI2 revealed that GLI2 is able to induce G1-S phase progression in contact-inhibited keratinocytes. Detailed time-course experiments identified E2F1 as early transcriptional target of GLI2. Further, we show that GLI2 expression in human keratinocytes results in a marked downregulation of epidermal differentiation markers. The data suggest a role for GLI2 in Hh-induced epidermal neoplasia by opposing epithelial cell cycle arrest signals and epidermal differentiation.
Assuntos
Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Inibição de Contato/fisiologia , Queratinócitos/citologia , Fatores de Transcrição/genética , Sequência de Bases , Linhagem Celular , Transformação Celular Neoplásica , Primers do DNA , Células Epidérmicas , Epiderme/efeitos dos fármacos , Epiderme/fisiologia , Humanos , Queratinócitos/fisiologia , Fatores de Transcrição Kruppel-Like , Proteínas Nucleares , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/fisiologia , Proteína Gli2 com Dedos de Zinco , Dedos de Zinco/genética , Dedos de Zinco/fisiologiaRESUMO
BACKGROUND: Lysosomal acid lipase (LAL), encoded by the LIPA gene, catalyzes the intracellular hydrolysis of cholesteryl esters and triglycerides in hepatocytes and macrophages. LIPA defects cause accumulation of these lipids in lysosomes. LAL deficiency (LAL D) presents and progresses as a continuum with dyslipidemia, hepatomegaly, and liver fibrosis. OBJECTIVE: To improve the understanding of the genetic basis of LAL D, an underappreciated cause of dyslipidemia and cirrhosis, we studied DNA samples from patients with various phenotypes of dyslipidemia. METHODS: Participants (N = 1357) were identified by lipid profiles and screened for the common disease causing LIPA exon 8 skipping splice-site mutation (c.894G>A; p.Ser275_Gln298del; rs116928232). RESULTS: Six patients were heterozygous for this variant. Complete LIPA sequencing revealed a patient, subsequently confirmed to have LAL D, with a heterozygous frameshift mutation involving deletion of exon 4 (p.Gly77Valfs*17 c.230-106_c.428+541del). A family study revealed a sister with the same genotype and phenotype. Genetic, clinical, and lipoprotein profiles of these sisters plus 6 additional family members are reported. Profiles of 2 other LAL D patients monitored for 2 decades are presented. Cholesterol homeostasis was studied to investigate rates of cholesterol synthesis and absorption in 4 LAL D patients. High-density lipoprotein (HDL) subspecies were also analyzed. CONCLUSIONS: We used this LIPA sequencing strategy (detection of the relatively common exon 8 variant followed by complete gene sequencing to identify additional mutations) as a means to further elucidate the genetic basis of LAL D among individuals with a suggestive clinical phenotype.
Assuntos
Metabolômica , Doença de Wolman/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Mutação , Esterol Esterase/genética , Doença de Wolman/sangue , Doença de Wolman/enzimologia , Doença de Wolman/genética , Adulto Jovem , Doença de WolmanRESUMO
Thyroid eye disease (TED) is a chronic debilitating condition causing physical discomfort, facial disfigurement and impaired visual function. The physical consequences of TED could have a negative and lasting impact on patients' employment, hobbies and psychosocial function. In this review, we assess the evidence of the impact of TED on patients' quality of life (QOL) and also explore the effects of suboptimal quality of care on QOL of patients with this disease. It is hoped that recent initiatives, including the Amsterdam declaration, to raise the quality of care for patients with TED will help to improve their QOL.