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1.
Cancer ; 129(4): 600-613, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36541021

RESUMO

BACKGROUND: Pleuropulmonary blastoma (PPB) is the most common lung cancer of infancy and early childhood. Type I PPB is a purely cystic lesion that has a microscopic population of primitive small cells with or without rhabdomyoblastic features and may progress to type II or III PPB, whereas type Ir lacks primitive small cells. METHODS: Children with suspected PPB were enrolled in the International PPB/DICER1 Registry. Pathology was centrally reviewed, and follow-up was ascertained annually. RESULTS: Between 2006 and 2022, 205 children had centrally reviewed type I or Ir PPB; 39% of children with type I and 5% of children with type Ir PPB received chemotherapy. Outcomes were favorable, although 11 children (nine with type I and two with type Ir PPB) experienced progression to type II/III (n = 8) or regrowth of type I PPB at the surgical site (n = 3), none of whom received chemotherapy before progression. Age and cyst size in combination were more suitable than either factor alone in predicting whether a particular lesion was type I or Ir PPB. CONCLUSIONS: For young children with type I PPB, outcomes are favorable, but complete resection is indicated because of the risk for progression. Chemotherapy may be useful in a subset of children at increased risk for recurrence/progression. Efforts to risk stratify children with type I PPB to optimize outcomes while reducing treatment-related side effects are underway.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Neoplasias Pulmonares , Blastoma Pulmonar , Criança , Humanos , Pré-Escolar , Blastoma Pulmonar/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Sistema de Registros , Ribonuclease III , RNA Helicases DEAD-box
2.
Curr Issues Mol Biol ; 44(2): 686-698, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35723333

RESUMO

Adult-type granulosa cell tumor (AGCT) is a rare ovarian malignancy characterized by slow growth and hormonal activity. The prognosis of AGCT is generally favorable, but one-third of patients with low-stage disease experience a late relapse, and over half of them die of AGCT. To identify markers that would distinguish patients at risk for relapse, we performed Lexogen QuantSeq 3' mRNA sequencing on formalin-fixed paraffin-embedded, archival AGCT tissue samples tested positive for the pathognomonic Forkhead Box L2 (FOXL2) mutation. We compared the transcriptomic profiles of 14 non-relapsed archival primary AGCTs (follow-up time 17-26 years after diagnosis) with 13 relapsed primary AGCTs (follow-up time 1.7-18 years) and eight relapsed tumors (follow-up time 2.8-18.9 years). Non-relapsed and relapsed primary AGCTs had similar transcriptomic profiles. In relapsed tumors three genes were differentially expressed: plasmalemma vesicle associated protein (PLVAP) was upregulated (p = 0.01), whereas argininosuccinate synthase 1 (ASS1) (p = 0.01) and perilipin 4 (PLIN4) (p = 0.02) were downregulated. PLVAP upregulation was validated using tissue microarray RNA in situ hybridization. In our patient cohort with extremely long follow-up, we observed similar gene expression patterns in both primary AGCT groups, suggesting that relapse is not driven by transcriptomic changes. These results reinforce earlier findings that molecular markers do not predict AGCT behavior or risk of relapse.

3.
Proc Natl Acad Sci U S A ; 116(49): 24593-24599, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31754026

RESUMO

Hematopoiesis, the formation of blood cells, involves the hierarchical differentiation of immature blast cells into mature, functional cell types and lineages of the immune system. Hematopoietic stem cells precisely regulate self-renewal versus differentiation to balance the production of blood cells and maintenance of the stem cell pool. The canonical view of acute myeloid leukemia (AML) is that it results from a combination of molecular events in a hematopoietic stem cell that block differentiation and drive proliferation. These events result in the accumulation of primitive hematopoietic blast cells in the blood and bone marrow. We used mathematical modeling to determine the impact of varying differentiation rates on myeloblastic accumulation. Our model shows that, instead of the commonly held belief that AML results from a complete block of differentiation of the hematopoietic stem cell, even a slight skewing of the fraction of cells that differentiate would produce an accumulation of blasts. We confirmed this model by interphase fluorescent in situ hybridization (FISH) and sequencing of purified cell populations from patients with AML, which showed that different leukemia-causing molecular abnormalities typically thought to block differentiation were consistently present in mature myeloid cells such as neutrophils and monocytes at similar levels to those in immature myeloid cells. These findings suggest reduced or skewed, rather than blocked, differentiation is responsible for the development of AML. Approaches that restore normal regulation of hematopoiesis could be effective treatment strategies.


Assuntos
Crise Blástica/patologia , Diferenciação Celular/fisiologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Modelos Biológicos , Adolescente , Adulto , Idoso , Morte Celular , Feminino , Regulação Leucêmica da Expressão Gênica , Hematopoese , Células-Tronco Hematopoéticas/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Células Mieloides/patologia , Fatores de Transcrição/genética
4.
Pediatr Blood Cancer ; 68(9): e29196, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34180131

RESUMO

Sickle hepatopathy comprises a spectrum of disorders that vary in severity. Intravascular sickling and sinusoidal occlusion are the principal drivers of sickle hepatopathy, but infection or autoimmunity can act as triggers. We describe two cases of acute sickle hepatopathy initiated by primary Epstein-Barr virus (EBV) infection, a previously unreported association. The first case entailed a 14-year-old girl with hemoglobin SC (HbSC) disease who developed hepatic sequestration crisis that responded to a simple transfusion of erythrocytes. The second case was that of a 16-year-old boy with HbSC disease who experienced life-threatening intrahepatic cholestasis with multiorgan failure.


Assuntos
Anemia Falciforme , Colestase Intra-Hepática , Infecções por Vírus Epstein-Barr , Doença da Hemoglobina SC , Adolescente , Anemia Falciforme/complicações , Colestase Intra-Hepática/etiologia , Infecções por Vírus Epstein-Barr/complicações , Feminino , Doença da Hemoglobina SC/complicações , Herpesvirus Humano 4 , Humanos , Masculino
5.
Nature ; 520(7546): 230-3, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25830876

RESUMO

Maternal age is a risk factor for congenital heart disease even in the absence of any chromosomal abnormality in the newborn. Whether the basis of this risk resides with the mother or oocyte is unknown. The impact of maternal age on congenital heart disease can be modelled in mouse pups that harbour a mutation of the cardiac transcription factor gene Nkx2-5 (ref. 8). Here, reciprocal ovarian transplants between young and old mothers establish a maternal basis for the age-associated risk in mice. A high-fat diet does not accelerate the effect of maternal ageing, so hyperglycaemia and obesity do not simply explain the mechanism. The age-associated risk varies with the mother's strain background, making it a quantitative genetic trait. Most remarkably, voluntary exercise, whether begun by mothers at a young age or later in life, can mitigate the risk when they are older. Thus, even when the offspring carry a causal mutation, an intervention aimed at the mother can meaningfully reduce their risk of congenital heart disease.


Assuntos
Envelhecimento/fisiologia , Cardiopatias/congênito , Cardiopatias/prevenção & controle , Idade Materna , Condicionamento Físico Animal/fisiologia , Prenhez/fisiologia , Idade de Início , Envelhecimento/genética , Animais , Animais Recém-Nascidos , Dieta Hiperlipídica , Feminino , Predisposição Genética para Doença , Coração/fisiologia , Coração/fisiopatologia , Cardiopatias/etiologia , Cardiopatias/genética , Proteína Homeobox Nkx-2.5 , Proteínas de Homeodomínio/genética , Hiperglicemia , Camundongos , Obesidade , Ovário/transplante , Fenótipo , Gravidez , Prenhez/genética , Locos de Características Quantitativas/genética , Risco , Fatores de Transcrição/genética
6.
Prev Sci ; 22(4): 509-522, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33453043

RESUMO

There is growing evidence that crime is strongly concentrated in micro-geographic hot spots, a fact that has led to the wide-scale use of hot spots policing programs. Such programs are ordinarily focused on deterrence due to police presence, or other law enforcement interventions at hot spots. However, preliminary basic research studies suggest that informal social controls may also be an important mechanism for crime reduction on high crime streets. Such research has been hindered by a lack of data on social and attitudinal characteristics of residents, and the fact that census information is not available at the micro-geographic level. Our study, conducted in Baltimore, MD, on a sample of 449 residential street segments, overcame these limitations by collecting an average of eight surveys (N = 3738), as well as physical observations, on segments studied. This unique primary data collection allowed us to develop the first direct indicators of collective efficacy at the micro-geographic level, as well as a wide array of indicators of other possible risk and protective factors for crime. Using multilevel negative binomial regression models, we also take into account community-level influences, and oversample crime hot spots to allow for robust comparisons across streets. Our study confirms the importance of opportunity features of streets such as population size and business activity in understanding crime, but also shows that informal social controls, as reflected by collective efficacy, are key for understanding crime on high crime streets. We argue that it is time for police, other city agencies, and NGOs to begin to work together to consider how informal social controls can be used to reduce crime at residential crime hot spots.


Assuntos
Crime , Aplicação da Lei , Controles Informais da Sociedade , Baltimore , Crime/prevenção & controle , Humanos , Polícia , Inquéritos e Questionários
7.
Am J Pathol ; 189(8): 1501-1504, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31202722

RESUMO

This commentary highlights the article by Clerbaux et al that describes the critical role of invasive ductular reaction in hepatocellular injury.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Roedores
8.
Blood ; 131(4): 408-416, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29092827

RESUMO

Severe congenital neutropenia (SCN) and Shwachman-Diamond syndrome (SDS) are congenital neutropenia syndromes with a high rate of leukemic transformation. Hematopoietic stressors may contribute to leukemic transformation by increasing the mutation rate in hematopoietic stem/progenitor cells (HSPCs) and/or by promoting clonal hematopoiesis. We sequenced the exome of individual hematopoietic colonies derived from 13 patients with congenital neutropenia to measure total mutation burden and performed error-corrected sequencing on a panel of 46 genes on 80 patients with congenital neutropenia to assess for clonal hematopoiesis. An average of 3.6 ± 1.2 somatic mutations per exome was identified in HSPCs from patients with SCN compared with 3.9 ± 0.4 for healthy controls (P = NS). Clonal hematopoiesis due to mutations in TP53 was present in 48% (13/27) of patients with SDS but was not seen in healthy controls (0/17, P < .001) or patients with SCN (0/40, P < .001). Our SDS cohort was young (median age 6.3 years), and many of the patients had multiple TP53 mutations. Conversely, clonal hematopoiesis due to mutations of CSF3R was present in patients with SCN but was not detected in healthy controls or patients with SDS. These data show that hematopoietic stress, including granulocyte colony-stimulating factor, do not increase the mutation burden in HSPCs in congenital neutropenia. Rather, distinct hematopoietic stressors result in the selective expansion of HSPCs carrying specific gene mutations. In particular, in SDS there is enormous selective pressure to expand TP53-mutated HSPCs, suggesting that acquisition of TP53 mutations is an early, likely initiating event, in the transformation to myelodysplastic syndrome/acute myeloid leukemia in patients with SDS.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas/patologia , Mutação , Neutropenia/congênito , Adolescente , Adulto , Criança , Pré-Escolar , Síndrome Congênita de Insuficiência da Medula Óssea , Exoma , Feminino , Células-Tronco Hematopoéticas/metabolismo , Humanos , Masculino , Taxa de Mutação , Neutropenia/genética , Neutropenia/patologia , Neutropenia/fisiopatologia , Adulto Jovem
9.
Hemoglobin ; 44(1): 67-69, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31985299

RESUMO

A novel unstable Gγ-globin variant, Hb F-Wentzville [Gγ24(B6)Gly→Glu; HBG2: c.74G>A, (p.Gly25Glu)], was identified in a young infant who required a single transfusion of erythrocytes for hemolytic anemia. This is the first reported γ-globin variant affecting the highly conserved glycine residue at helical position B6. In the tertiary structure of hemoglobin (Hb), glycine at B6 is in close proximity to another invariant glycine residue at E8. Prior studies have shown that replacement of the B6 or E8 glycine residues with bulkier amino acids disrupts packing between the B and E helices, resulting in Hb instability. Thus, Hb F-Wentzville is analogous to the following unstable ß-globin B6 variants: Hb Savannah (HBB: c.74G>T, p.Gly24Val), Hb Riverdale-Bronx (HBB: c.73G>C, p.Gly24Arg), and Hb Moscva (HBB: c.74G>A, p.Gly24Asp).


Assuntos
Anemia Hemolítica/genética , Hemoglobina Fetal/genética , Mutação , gama-Globinas/genética , Anemia Hemolítica/diagnóstico , Anemia Hemolítica/patologia , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Expressão Gênica , Heterozigoto , Humanos , Lactente , Masculino , Estabilidade Proteica , Análise de Sequência de DNA , gama-Globinas/deficiência
10.
Blood ; 139(15): 2266-2268, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35420686
14.
Am J Physiol Gastrointest Liver Physiol ; 314(5): G547-G558, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29388792

RESUMO

Biliary atresia (BA), a neonatal liver disease, is characterized by obstruction of extrahepatic bile ducts with subsequent cholestasis, inflammation, and progressive liver fibrosis. To gain insights into the pathophysiology of BA, we focused attention on GATA6, a transcription factor implicated in biliary development. Early in fetal development GATA6 expression is evident in cholangiocytes and hepatocytes, but by late gestation it is extinguished in hepatocytes. Utilizing a unique set of BA liver samples collected before and after successful portoenterostomy (PE), we found that GATA6 expression is markedly upregulated in hepatocytes of patients with BA compared with healthy and cholestatic disease controls. This upregulation is recapitulated in two murine models simulating bile duct obstruction and intrahepatic bile ductule expansion. GATA6 expression in BA livers correlates with two established negative prognostic indicators (age at PE, degree of intrahepatic bile ductule expansion) and decreases after normalization of serum bilirubin by PE. GATA6 expression in BA livers correlates with expression of known regulators of cholangiocyte differentiation ( JAGGED1, HNF1ß, and HNF6). These same genes are upregulated after enforced expression of GATA6 in human hepatocyte cell models. In conclusion, GATA6 is a novel marker and a putative driver of hepatocyte-cholangiocyte metaplasia in BA, and its expression in hepatocytes is downregulated after successful PE. NEW & NOTEWORTHY A pathological hallmark in the liver of patients with biliary atresia is ductular reaction, an expansion of new bile ductules that are thought to arise from conversion of mature hepatocytes. Here, we show that transcription factor GATA6 is a marker and potential driver of hepatocyte ductal metaplasia in biliary atresia. Hepatocyte GATA6 expression is elevated in biliary atresia, correlates with bile duct expansion, and decreases after successful portoenterostomy.


Assuntos
Ductos Biliares Extra-Hepáticos/patologia , Atresia Biliar , Fator de Transcrição GATA6/metabolismo , Hepatócitos/metabolismo , Fígado/patologia , Animais , Atresia Biliar/metabolismo , Atresia Biliar/patologia , Atresia Biliar/cirurgia , Biomarcadores/metabolismo , Transdiferenciação Celular/fisiologia , Colestase/metabolismo , Modelos Animais de Doenças , Células Hep G2 , Humanos , Metaplasia/metabolismo , Metaplasia/patologia , Camundongos , Portoenterostomia Hepática/métodos
15.
Tumour Biol ; 40(7): 1010428318785498, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30074440

RESUMO

GATA4, a transcription factor crucial for early liver development, has been implicated in the pathophysiology of hepatoblastoma, an embryonal tumor of childhood. However, the molecular and phenotypic consequences of GATA4 expression in hepatoblastoma are not fully understood. We surveyed GATA4 expression in 24 hepatoblastomas using RNA in situ hybridization and immunohistochemistry. RNA interference was used to inhibit GATA4 in human HUH6 hepatoblastoma cells, and changes in cell migration were measured with wound healing and transwell assays. RNA microarray hybridization was performed on control and GATA4 knockdown HUH6 cells, and differentially expressed genes were validated by quantitative polymerase chain reaction or immunostaining. Plasmid transfection was used to overexpress GATA4 in primary human hepatocytes and ensuring changes in gene expression were measured by quantitative polymerase chain reaction. We found that GATA4 expression was high in most hepatoblastomas but weak or negligible in normal hepatocytes. GATA4 gene silencing impaired HUH6 cell migration. We identified 106 differentially expressed genes (72 downregulated, 34 upregulated) in knockdown versus control HUH6 cells. GATA4 silencing altered the expression of genes associated with cytoskeleton organization, cell-to-cell adhesion, and extracellular matrix dynamics (e.g. ADD3, AHNAK, DOCK8, RHOU, MSF, IGFBP1, COL4A2). These changes in gene expression reflected a more epithelial (less malignant) phenotype. Consistent with this notion, there was reduced F-actin stress fiber formation in knockdown HUH6 cells. Forced expression of GATA4 in primary human hepatocytes triggered opposite changes in the expression of genes identified by GATA4 silencing in HUH6 cells. In conclusion, GATA4 is highly expressed in most hepatoblastomas and correlates with a mesenchymal, migratory phenotype of hepatoblastoma cells.


Assuntos
Movimento Celular , Fator de Transcrição GATA4/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Hepatoblastoma/patologia , Neoplasias Hepáticas/patologia , Mesoderma/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Proliferação de Células , Criança , Pré-Escolar , Feminino , Fator de Transcrição GATA4/antagonistas & inibidores , Fator de Transcrição GATA4/genética , Hepatoblastoma/genética , Humanos , Lactente , Neoplasias Hepáticas/genética , Masculino , Mesoderma/metabolismo , Pessoa de Meia-Idade , Prognóstico , RNA Interferente Pequeno/genética , Adulto Jovem
16.
Cochrane Database Syst Rev ; 12: CD011315, 2018 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-30577083

RESUMO

BACKGROUND: Amphetamine-type stimulants (ATS) refer to a group of synthetic stimulants including amphetamine, methamphetamine, 3,4-methylenedioxy-methamphetamine (MDMA) and related substances. ATS are highly addictive and prolonged use may result in a series of mental and physical symptoms including anxiety, confusion, insomnia, mood disturbances, cognitive impairments, paranoia, hallucinations and delusion.Currently there is no widely accepted treatment for ATS-use disorder. However, cognitive-behavioural treatment (CBT) is the first-choice treatment. The effectiveness of CBT for other substance-use disorders (e.g. alcohol-, opioid- and cocaine-use disorders) has been well documented and as such this basic treatment approach has been applied to the ATS-use disorder. OBJECTIVES: To investigate the efficacy of cognitive-behavioural treatment for people with ATS-use disorder for reducing ATS use compared to other types of psychotherapy, pharmacotherapy, 12-step facilitation, no intervention or treatment as usual. SEARCH METHODS: We identified randomised controlled trials (RCT) and quasi-RCTs comparing CBT for ATS-use disorders with other types of psychotherapy, pharmacotherapy, 12 step facilitation or no intervention. We searched the Cochrane Drugs and Alcohol Group Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE via PubMed, Embase and five other databases up to July 2018. In addition, we examined reference lists of eligible studies and other systematic reviews. We contacted experts in the field. SELECTION CRITERIA: Eligibility criteria consisted of RCTs and quasi-RCTs comparing CBT versus other types of interventions with adult ATS users (aged 18 years or older) diagnosed by any explicit diagnostic system. Primary outcomes included abstinence rate and other indicators of drug-using behaviours. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: Only two studies met the eligibility criteria. Both studies were at low risk of selection bias and reporting bias. In one study, almost half of participants in the intervention group dropped out and this study was at high risk of attrition bias. The studies compared a single session of brief CBT or a web-based CBT to a waiting-list control (total sample size across studies of 129). Results were mixed across the studies. For the single-session brief CBT study, two out of five measures of drug use produced significant results, percentage of abstinent days in 90 days (odds ratio (OR) 0.22, 95% confidence interval (CI) 0.02 to 2.11) and dependence symptoms (standardised mean difference (SMD) -0.59, 95% CI -1.16 to -0.02). Little confidence could be placed in the results from this study give the small sample size (25 participants per group) and corresponding large CIs around the observed effects. For the web-based CBT, there was no significant difference across different outcomes. Neither study reported adverse effects. The meta-analytic mean across these two trials for drug use was not significant (SMD -0.28, 95% CI -0.69 to 0.14). In summary, overall quality of evidence was low and there was insufficient evidence to conclude that CBT is effective, or ineffective, at treating ATS use. AUTHORS' CONCLUSIONS: Currently, there is not enough evidence to establish the efficacy of CBT for ATS-use disorders because of a paucity of high-quality research in this area.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/terapia , Anfetaminas , Terapia Cognitivo-Comportamental/métodos , Adulto , Transtornos Relacionados ao Uso de Anfetaminas/complicações , Anfetaminas/efeitos adversos , Feminino , Humanos , Masculino , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , Listas de Espera
17.
Biochim Biophys Acta Proteins Proteom ; 1865(10): 1237-1245, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28648523

RESUMO

Thermostable α-amylases have many industrial applications and are therefore continuously explored from novel sources. We present the characterization of a novel putative α-amylase gene product (Tp-AmyS) cloned from Thermotoga petrophila. The purified recombinant enzyme is highly thermostable and able to hydrolyze starch into dextrin between 90 and 100°C, with optimum activity at 98°C and pH8.5. The activity increased in the presence of Rb1+, K1+ and Ca2+ ions, whereas other ions inhibited activity. The crystal structure of Tp-AmyS at 1.7Å resolution showed common features of the GH-13 family, however was apparently found to be a dimer. Several residues from one monomer interacted with a docked acarbose, an inhibitor of Tp-AmyS, in the other monomer, suggesting catalytic cooperativity within the dimer. The most striking feature of the dimer was that it resembled the dimerization of salivary amylase from a previous crystal structure, and thus could be a functional feature of some amylases.


Assuntos
Bactérias/química , Proteínas de Bactérias/química , alfa-Amilases/química , Catálise , Clonagem Molecular/métodos , Dextrinas/química , Dimerização , Estabilidade Enzimática , Estabilidade Proteica , Proteínas Recombinantes/química , Especificidade por Substrato , Temperatura
18.
Reproduction ; 154(4): 455-467, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28710293

RESUMO

Testicular Leydig cells produce androgens essential for proper male reproductive development and fertility. Here, we describe a new Leydig cell ablation model based on Cre/Lox recombination of mouse Gata4 and Gata6, two genes implicated in the transcriptional regulation of steroidogenesis. The testicular interstitium of adult Gata4flox/flox ; Gata6flox/flox mice was injected with adenoviral vectors encoding Cre + GFP (Ad-Cre-IRES-GFP) or GFP alone (Ad-GFP). The vectors efficiently and selectively transduced Leydig cells, as evidenced by GFP reporter expression. Three days after Ad-Cre-IRES-GFP injection, expression of androgen biosynthetic genes (Hsd3b1, Cyp17a1 and Hsd17b3) was reduced, whereas expression of another Leydig cell marker, Insl3, was unchanged. Six days after Ad-Cre-IRES-GFP treatment, the testicular interstitium was devoid of Leydig cells, and there was a concomitant loss of all Leydig cell markers. Chromatin condensation, nuclear fragmentation, mitochondrial swelling, and other ultrastructural changes were evident in the degenerating Leydig cells. Liquid chromatography-tandem mass spectrometry demonstrated reduced levels of androstenedione and testosterone in testes from mice injected with Ad-Cre-IRES-GFP. Late effects of treatment included testicular atrophy, infertility and the accumulation of lymphoid cells in the testicular interstitium. We conclude that adenoviral-mediated gene delivery is an expeditious way to probe Leydig cell function in vivo Our findings reinforce the notion that GATA factors are key regulators of steroidogenesis and testicular somatic cell survival.Free Finnish abstract: A Finnish translation of this abstract is freely available at http://www.reproduction-online.org/content/154/4/455/suppl/DC2.


Assuntos
Adenoviridae/genética , Fator de Transcrição GATA4/metabolismo , Fator de Transcrição GATA6/metabolismo , Vetores Genéticos , Células Intersticiais do Testículo/metabolismo , Transdução Genética , 17-Hidroxiesteroide Desidrogenases/genética , 17-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Sobrevivência Celular , Feminino , Fertilidade , Fator de Transcrição GATA4/deficiência , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA6/deficiência , Fator de Transcrição GATA6/genética , Genótipo , Hormônios Esteroides Gonadais/biossíntese , Insulina/genética , Insulina/metabolismo , Integrases/genética , Células Intersticiais do Testículo/ultraestrutura , Masculino , Camundongos Knockout , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Fenótipo , Gravidez , Progesterona Redutase/genética , Progesterona Redutase/metabolismo , Proteínas/genética , Proteínas/metabolismo , Transdução de Sinais , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo , Esteroide Isomerases/genética , Esteroide Isomerases/metabolismo , Fatores de Tempo
19.
Tumour Biol ; 39(3): 1010428317695016, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28349834

RESUMO

Hepatoblastoma, the most common type of pediatric liver cancer, is treated with a combination of surgery and chemotherapy. An essential drug in the treatment of hepatoblastoma is doxorubicin, which in high doses is cardiotoxic. This adverse effect is due to downregulation of cardiac expression of transcription factor GATA4, leading in turn to diminished levels of anti-apoptotic BCL2 (B-cell lymphoma 2) protein family members. GATA4 is also expressed in early fetal liver, but absent from normal postnatal hepatocytes. However, GATA4 is highly expressed in hepatoblastoma tissue. In this study, we assessed the role of GATA4 in doxorubicin-induced apoptosis of hepatoblastoma cells. Herein, we demonstrate that doxorubicin decreases GATA4 expression and alters the expression pattern of BCL2 family members, most profoundly that of BCL2 and BAK, in the HUH6 hepatoblastoma cell line. Silencing of GATA4 by siRNA prior to doxorubicin treatment sensitizes HUH6 cells to the apoptotic effect of this drug by further shifting the balance of BCL2 family members to the pro-apoptotic direction. Specifically, expression levels of anti-apoptotic BCL2 were decreased and pro-apoptotic BID were increased after GATA4 silencing. On the whole, our results indicate that since high endogenous levels of transcription factor GATA4 likely protect hepatoblastoma cells from doxorubicin-induced apoptosis, these cells can be rendered more sensitive to the drug by downregulation of GATA4.


Assuntos
Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Fator de Transcrição GATA4/biossíntese , Hepatoblastoma/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina , Fator de Transcrição GATA4/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hepatoblastoma/genética , Hepatoblastoma/patologia , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , RNA Interferente Pequeno
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