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1.
Proc Natl Acad Sci U S A ; 120(10): e2219439120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36853944

RESUMO

Multiple myeloma (MM), a tumor of germinal center (GC)-experienced plasma cells, comprises distinct genetic subgroups, such as the t(11;14)/CCND1 and the t(4;14)/MMSET subtype. We have generated genetically defined, subgroup-specific MM models by the GC B cell-specific coactivation of mouse Ccnd1 or MMSET with a constitutively active Ikk2 mutant, mimicking the secondary NF-κB activation frequently seen in human MM. Ccnd1/Ikk2ca and MMSET/Ikk2ca mice developed a pronounced, clonally restricted plasma cell outgrowth with age, accompanied by serum M spikes, bone marrow insufficiency, and bone lesions. The transgenic plasma cells could be propagated in vivo and showed distinct transcriptional profiles, resembling their human MM counterparts. Thus, we show that targeting the expression of genes involved in MM subgroup-specific chromosomal translocations into mouse GC B cells translates into distinct MM-like diseases that recapitulate key features of the human tumors, opening the way to a better understanding of the pathogenesis and therapeutic vulnerabilities of different MM subgroups.


Assuntos
Mieloma Múltiplo , Humanos , Animais , Camundongos , Mieloma Múltiplo/genética , Plasmócitos , Linfócitos B , Genes cdc , Animais Geneticamente Modificados , Modelos Animais de Doenças
2.
JAMA Pediatr ; 175(8): 827-836, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33900383

RESUMO

Importance: Atypical eye gaze is an early-emerging symptom of autism spectrum disorder (ASD) and holds promise for autism screening. Current eye-tracking methods are expensive and require special equipment and calibration. There is a need for scalable, feasible methods for measuring eye gaze. Objective: Using computational methods based on computer vision analysis, we evaluated whether an app deployed on an iPhone or iPad that displayed strategically designed brief movies could elicit and quantify differences in eye-gaze patterns of toddlers with ASD vs typical development. Design, Setting, and Participants: A prospective study in pediatric primary care clinics was conducted from December 2018 to March 2020, comparing toddlers with and without ASD. Caregivers of 1564 toddlers were invited to participate during a well-child visit. A total of 993 toddlers (63%) completed study measures. Enrollment criteria were aged 16 to 38 months, healthy, English- or Spanish-speaking caregiver, and toddler able to sit and view the app. Participants were screened with the Modified Checklist for Autism in Toddlers-Revised With Follow-up during routine care. Children were referred by their pediatrician for diagnostic evaluation based on results of the checklist or if the caregiver or pediatrician was concerned. Forty toddlers subsequently were diagnosed with ASD. Exposures: A mobile app displayed on a smartphone or tablet. Main Outcomes and Measures: Computer vision analysis quantified eye-gaze patterns elicited by the app, which were compared between toddlers with ASD vs typical development. Results: Mean age of the sample was 21.1 months (range, 17.1-36.9 months), and 50.6% were boys, 59.8% White individuals, 16.5% Black individuals, 23.7% other race, and 16.9% Hispanic/Latino individuals. Distinctive eye-gaze patterns were detected in toddlers with ASD, characterized by reduced gaze to social stimuli and to salient social moments during the movies, and previously unknown deficits in coordination of gaze with speech sounds. The area under the receiver operating characteristic curve discriminating ASD vs non-ASD using multiple gaze features was 0.90 (95% CI, 0.82-0.97). Conclusions and Relevance: The app reliably measured both known and new gaze biomarkers that distinguished toddlers with ASD vs typical development. These novel results may have potential for developing scalable autism screening tools, exportable to natural settings, and enabling data sets amenable to machine learning.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Fixação Ocular , Aplicativos Móveis , Pré-Escolar , Computadores de Mão , Feminino , Humanos , Lactente , Masculino , Atenção Primária à Saúde , Estudos Prospectivos
3.
J Child Psychol Psychiatry ; 62(9): 1120-1131, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33641216

RESUMO

BACKGROUND: This study is part of a larger research program focused on developing objective, scalable tools for digital behavioral phenotyping. We evaluated whether a digital app delivered on a smartphone or tablet using computer vision analysis (CVA) can elicit and accurately measure one of the most common early autism symptoms, namely failure to respond to a name call. METHODS: During a pediatric primary care well-child visit, 910 toddlers, 17-37 months old, were administered an app on an iPhone or iPad consisting of brief movies during which the child's name was called three times by an examiner standing behind them. Thirty-seven toddlers were subsequently diagnosed with autism spectrum disorder (ASD). Name calls and children's behavior were recorded by the camera embedded in the device, and children's head turns were coded by both CVA and a human. RESULTS: CVA coding of response to name was found to be comparable to human coding. Based on CVA, children with ASD responded to their name significantly less frequently than children without ASD. CVA also revealed that children with ASD who did orient to their name exhibited a longer latency before turning their head. Combining information about both the frequency and the delay in response to name improved the ability to distinguish toddlers with and without ASD. CONCLUSIONS: A digital app delivered on an iPhone or iPad in real-world settings using computer vision analysis to quantify behavior can reliably detect a key early autism symptom-failure to respond to name. Moreover, the higher resolution offered by CVA identified a delay in head turn in toddlers with ASD who did respond to their name. Digital phenotyping is a promising methodology for early assessment of ASD symptoms.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtorno do Espectro Autista/diagnóstico , Transtorno Autístico/diagnóstico , Criança , Pré-Escolar , Humanos , Lactente
4.
Child Adolesc Psychiatr Clin N Am ; 26(4): 761-770, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28916012

RESUMO

An estimated 1 in 5 children in the United States meet criteria for a diagnosable mental disorder, yet fewer than 20% receive mental health services. Unmet need for psychiatric treatment may contribute to patterns of increasing use of the emergency department. This article describes an integrated pediatric evaluation center designed to prevent the need for treatment in emergency settings by increasing access to timely and appropriate care for emergent and critical mental health needs. Preliminary results showed that the center provided rapid access to assessment and treatment services for children and adolescents presenting with a wide range of psychiatric concerns.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Necessidades e Demandas de Serviços de Saúde/organização & administração , Serviços de Saúde Mental/organização & administração , Pediatria , Adolescente , Criança , Serviço Hospitalar de Emergência/estatística & dados numéricos , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Estados Unidos
5.
Ann Intern Med ; 161(7): 472-81, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25285540

RESUMO

BACKGROUND: Hospitals are implementing discharge support programs to reduce readmissions, and these programs have had mixed success. OBJECTIVE: To examine whether a peridischarge, nurse-led intervention decreased emergency department (ED) visits or readmissions among ethnically and linguistically diverse older patients admitted to a safety-net hospital. DESIGN: Randomized, controlled trial using computer-generated randomization with 1:1 allocation, stratified by language. (Clinical Trials.gov: NCT01221532). SETTING: Publicly funded urban hospital in Northern California. PATIENTS: Hospitalized adults aged 55 years or older with anticipated discharge to the community who spoke English, Spanish, or Chinese (Mandarin or Cantonese). INTERVENTION: Usual care versus in-hospital, one-on-one, self-management education given by a dedicated language-concordant registered nurse combined with a telephone follow-up after discharge from a nurse practitioner. MEASUREMENTS: Staff blinded to the study groups determined ED visits or readmissions to any facility at 30, 90, and 180 days after initial hospital discharge using administrative data from several hospitals. RESULTS: There were 700 low-income, ethnically and linguistically diverse patients with a mean age of 66.2 years (SD, 9.0). The primary outcome of ED visits or readmissions did not differ between the intervention and usual care groups (hazard ratio, 1.26 [95% CI, 0.89 to 1.78] at 30 days, 1.21 [CI, 0.91 to 1.62] at 90 days, and 1.11 [CI, 0.86 to 1.43] at 180 days). LIMITATIONS: This study was done at a single acute-care hospital. There were fewer outcomes than expected, which may have caused the study to be underpowered. CONCLUSION: A nurse-led, in-hospital discharge support intervention did not show a reduction in readmissions or ED visits among diverse, low-income older adults at a safety-net hospital. Although wide CIs preclude firm conclusions, the intervention may have increased ED visits. Alternative readmission prevention strategies should be tested in this population. PRIMARY FUNDING SOURCE: Gordon and Betty Moore Foundation.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Cuidados de Enfermagem , Alta do Paciente , Educação de Pacientes como Assunto , Readmissão do Paciente/estatística & dados numéricos , Idoso , California , Continuidade da Assistência ao Paciente , Feminino , Serviços de Assistência Domiciliar , Hospitais Urbanos , Humanos , Masculino , Pessoa de Meia-Idade , Pobreza , Provedores de Redes de Segurança
7.
Naunyn Schmiedebergs Arch Pharmacol ; 386(5): 383-91, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23397587

RESUMO

Connexin 43 is located in the cardiomyocyte sarcolemma and in the mitochondrial membrane. Sarcolemmal connexin 43 contributes to the spread of myocardial ischemia/reperfusion injury, whereas mitochondrial connexin 43 contributes to cardioprotection. We have now investigated the antiarrhythmic dipeptide ZP1609 (danegaptide), which is an analog of the connexin 43 targeting antiarrhythmic peptide rotigaptide (ZP123), in an established and clinically relevant experimental model of ischemia/reperfusion in pigs. Pigs were subjected to 60 min coronary occlusion and 3 h reperfusion. ZP1609 (n = 10) was given 10 min prior to reperfusion (75 µg/kg b.w. bolus i.v. + 57 µg/kg/min i.v. infusion for 3 h). Immediate full reperfusion (IFR, n = 9) served as control. Ischemic postconditioning (PoCo, n = 9; 1 min LAD reocclusion after 1 min reperfusion; four repetitions) was used as a positive control of cardioprotection. Infarct size (TTC) was determined as the end point of cardioprotection. Systemic hemodynamics and regional myocardial blood flow during ischemia were not different between groups. PoCo and ZP1609 reduced infarct size vs. IFR (IFR, 46 ± 4 % of area at risk; mean ± SEM; PoCo, 31 ± 4 %; ZP1609, 25 ± 5 %; both p < 0.05 vs. IFR; ANOVA). There were only few arrhythmias during reperfusion such that no antiarrhythmic action of ZP1609 was observed. ZP1609 when given before reperfusion reduces infarct size to a similar extent as ischemic postconditioning. Further studies are necessary to define the mechanism/action of ZP1609 on connexin 43 in cardiomyocytes.


Assuntos
Antiarrítmicos/uso terapêutico , Cardiotônicos/uso terapêutico , Dipeptídeos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Animais , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Suínos , Porco Miniatura
8.
Eur Heart J ; 34(42): 3314-21, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23242190

RESUMO

AIMS: Reperfusion injury following acute myocardial infarction impacts not only on the myocardium but also on the coronary microcirculation, and microembolization from the culprit lesion contributes to microvascular obstruction. Prior experimental studies have not accounted for microembolization in ischaemia/reperfusion injury and not considered microembolization as a confounder and target of protection by ischaemic postconditioning. We therefore investigated the impact of microembolization during reperfusion on infarct size and cardioprotection by postconditioning. METHODS AND RESULTS: Anaesthetized, open-chest pigs were subjected to 90 min low-flow ischaemia. Immediate full reperfusion (n = 8) served as the control. Microembolization was induced by intracoronary infusion of 42 µm microspheres with the onset of reperfusion (n = 8). In a second step, postconditioning was induced by six cycles of 20s reperfusion/20s re-occlusion without (n = 8) and with superimposed microembolization (n = 8). Transmural blood flow and area at risk were determined by radioactive microspheres, infarct size by triphenyl tetrazolium chloride staining. Area at risk and transmural blood flow were not different between groups. Microembolization increased infarct size from 32 ± 3% of the area at risk to 47 ± 3% (P < 0.05). Embolizing particles were re-distributed away from the central infarcted area and accumulated in the infarct border, thus contributing to infarct extension. Postconditioning reduced infarct size without (21 ± 3%; P < 0.05 vs. immediate full reperfusion) and also with additional microembolization (26 ± 5%; P < 0.05 vs. immediate full reperfusion and microembolization); embolizing particles did not accumulate in the infarct border. CONCLUSION: Microembolization at reperfusion augments infarct size, but postconditioning in the presence of microembolization still reduces infarct size and attenuates infarct expansion.


Assuntos
Embolia/etiologia , Pós-Condicionamento Isquêmico/métodos , Infarto do Miocárdio/terapia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Reperfusão Miocárdica/métodos , Animais , Modelos Animais de Doenças , Embolia/patologia , Cardiopatias/etiologia , Cardiopatias/patologia , Microesferas , Traumatismo por Reperfusão Miocárdica/patologia , Suínos , Porco Miniatura
9.
Funct Integr Genomics ; 11(4): 651-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21547435

RESUMO

Single feature polymorphisms (SFPs) are microarray-based molecular markers that are detected by hybridization of DNA or cRNA to oligonucleotide probes. With an objective to identify the potential polymorphic markers for drought tolerance in pigeonpea [Cajanus cajan (L.) Millspaugh], an important legume crop for the semi-arid tropics but deficient in genomic resources, Affymetrix Genome Arrays of soybean (Glycine max), a closely related species of pigeonpea were used on cRNA of six parental genotypes of three mapping populations of pigeonpea segregating for agronomic traits like drought tolerance and pod borer (Helicoverpa armigiera) resistance. By using robustified projection pursuit method on 15 pair-wise comparisons for the six parental genotypes, 5,692 SFPs were identified. Number of SFPs varied from 780 (ICPL 8755 × ICPL 227) to 854 (ICPL 151 × ICPL 87) per parental combination of the mapping populations. Randomly selected 179 SFPs were used for validation by Sanger sequencing and good quality sequence data were obtained for 99 genes of which 75 genes showed sequence polymorphisms. While associating the sequence polymorphisms with SFPs detected, true positives were observed for 52.6% SFPs detected. In terms of parental combinations of the mapping populations, occurrence of true positives was 34.48% for ICPL 151 × ICPL 87, 41.86% for ICPL 8755 × ICPL 227, and 81.58% for ICP 28 × ICPW 94. In addition, a set of 139 candidate genes that may be associated with drought tolerance has been identified based on gene ontology analysis of the homologous pigeonpea genes to the soybean genes that detected SFPs between the parents of the mapping populations segregating for drought tolerance.


Assuntos
Cajanus/genética , Desidratação/genética , Polimorfismo Genético , Cajanus/fisiologia , Secas , Perfilação da Expressão Gênica , Marcadores Genéticos , Genoma de Planta , Genótipo , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Fisiológico/genética
10.
PLoS One ; 3(10): e3562, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18958163

RESUMO

INTRODUCTION: Breast feeding has long term effects on the developing immune system which outlive passive immunization of the neonate. We have investigated the transfer of milk immune cells and examined the result of transfer once the recipients were adult. METHODS: Non-transgenic mouse pups were foster-nursed by green fluorescent protein (GFP) transgenic dams for 3 weeks and the fate of GFP+ cells was followed by FACS analysis, immunohistochemistry and RT-PCR for GFP and appropriate immune cell markers. Pups suckled by non-transgenic dams served as controls. RESULTS: Despite a preponderance of B cells and macrophages in the stomach contents of the pups, most cells undergoing trans-epithelial migration derived from the 3-4% of milk cells positive for T lymphocyte markers. These cells homed to the spleen and thymus, with maximal accumulation at 3-4 weeks. By sensitizing dams with an antigen which elicits a T cell-mediated delayed-type-hypersensitivity (DTH) response, we determined that nursing by a sensitized dam (compared to a non-sensitized dam) amplified a subsequent DTH response in females and yet suppressed one in males. DISCUSSION: These results suggest that clinical evaluation weighing the pros and cons of nursing male versus female children by mothers with genetically-linked hypersensitivity diseases, such as celiac disease and eczema, or those in regions of the world with endemic DTH-eliciting diseases, such as tuberculosis, may be warranted.


Assuntos
Transferência Adotiva , Hipersensibilidade Tardia/imunologia , Mucosa Intestinal/imunologia , Lactação/imunologia , Glândulas Mamárias Animais/imunologia , Caracteres Sexuais , Transferência Adotiva/veterinária , Animais , Animais Recém-Nascidos , Animais Lactentes , Movimento Celular/imunologia , Movimento Celular/fisiologia , Feminino , Mucosa Gástrica/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imunidade Materno-Adquirida/fisiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiologia , Masculino , Glândulas Mamárias Animais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estômago/citologia
11.
J Am Acad Child Adolesc Psychiatry ; 45(5): 538-549, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16601400

RESUMO

OBJECTIVE: To examine the test-retest reliability of a new interviewer-based psychiatric diagnostic measure (the Preschool Age Psychiatric Assessment) for use with parents of preschoolers aged 2 to 5 years. METHOD: A total of 1,073 parents of children attending a large pediatric clinic completed the Child Behavior Checklist 1 1/2-5. For 18 months, 193 parents of high scorers and 114 parents of low scorers were interviewed on two occasions an average of 11 days apart. RESULTS: Estimates of diagnostic reliability were very similar to those obtained from interviews with parents of older children and adults, with kappas ranging from 0.36 to 0.79. Test-retest intraclass correlations for DSM-IV syndrome scale scores ranged from 0.56 to 0.89. There were no significant differences in reliability by age, sex, or race (African American versus non-African American). CONCLUSIONS: The Preschool Age Psychiatric Assessment provides a reasonably reliable standardized measure of DSM-IV psychiatric symptoms and disorders in preschoolers for use in both research and clinical service evaluations of preschoolers as young as 2 years old.


Assuntos
Transtornos do Comportamento Infantil/diagnóstico , Entrevista Psicológica , Transtornos Mentais/diagnóstico , Determinação da Personalidade/estatística & dados numéricos , Transtornos do Comportamento Infantil/psicologia , Pré-Escolar , Manual Diagnóstico e Estatístico de Transtornos Mentais , Avaliação da Deficiência , Feminino , Humanos , Masculino , Programas de Rastreamento/estatística & dados numéricos , Transtornos Mentais/psicologia , Variações Dependentes do Observador , Psicometria/estatística & dados numéricos , Psicopatologia , Reprodutibilidade dos Testes
12.
Arch Dermatol Res ; 297(9): 417-20, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16389560

RESUMO

Solar radiation in the UVB range is absorbed primarily by the epidermal DNA where characteristic photodamage results in altered immune responses and mutagenic lesions. UVB exposure of the skin results in a profound upregulation of the anti-inflammatory cytokine, IL-10 and suppression of contact hypersensitivity (CHS). Given that IL-10 is produced after UVB exposure, and that antibodies against IL-10 have been shown to reverse UVB-induced immune suppression, we hypothesized that IL-10 transgenic mice would show an enhanced immune suppression in response to UVB. Using an IL-10 transgenic mouse model (IL-10tg), we examined the CHS response in unexposed animals and those exposed to UVB. Unexposed IL-10tg animals showed a diminished CHS response compared to wild-type. Surprisingly, however, when IL-10tg animals were exposed to UVB, the CHS response was not further suppressed, but rather was restored to the level observed in unexposed wild-type animals.


Assuntos
Dermatite de Contato/imunologia , Dermatite de Contato/fisiopatologia , Epiderme/efeitos da radiação , Interleucina-10/genética , Raios Ultravioleta , Animais , Antígenos CD4/análise , Contagem de Células , Células Dendríticas/química , Células Dendríticas/patologia , Células Dendríticas/efeitos da radiação , Dermatite de Contato/patologia , Epiderme/química , Epiderme/fisiopatologia , Citometria de Fluxo , Interleucina-10/fisiologia , Células de Langerhans/química , Células de Langerhans/patologia , Células de Langerhans/efeitos da radiação , Camundongos , Camundongos Transgênicos , Linfócitos T/química , Linfócitos T/patologia , Linfócitos T/efeitos da radiação , Regulação para Cima/efeitos da radiação
13.
Clin Neurosci Res ; 6(5): 237-245, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19169437

RESUMO

Neuroinflammation is a complex integration of the responses of all cells present within the CNS, including the neurons, macroglia, microglia and the infiltrating leukocytes. The initiating insult, environmental factors, genetic background and age/past experiences all combine to modulate the integrated response of this complex neuroinflammatory circuit. Here, we explore how these factors interact to lead to either neuroprotective versus neurotoxic inflammatory responses. We specifically focus on microglia and astrocytic regulation of autoreactive T cell responses.

14.
BMC Cancer ; 5: 135, 2005 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-16236176

RESUMO

BACKGROUND: UV-induced damage can induce apoptosis or trigger DNA repair mechanisms. Minor DNA damage is thought to halt the cell cycle to allow effective repair, while more severe damage can induce an apoptotic program. Of the two major types of UV-induced DNA lesions, it has been reported that repair of CPD, but not 6-4PP, abrogates mutation. To address whether the two major forms of UV-induced DNA damage, can induce differential biological effects, NER-deficient cells containing either CPD photolyase or 6-4 PP photolyase were exposed to UV and examined for alterations in cell cycle and apoptosis. In addition, pTpT, a molecular mimic of CPD was tested in vitro and in vivo for the ability to induce cell death and cell cycle alterations. METHODS: NER-deficient XPA cells were stably transfected with CPD-photolyase or 6-4PP photolyase to specifically repair only CPD or only 6-4PP. After 300 J/m2 UVB exposure photoreactivation light (PR, UVA 60 kJ/m2) was provided for photolyase activation and DNA repair. Apoptosis was monitored 24 hours later by flow cytometric analysis of DNA content, using sub-G1 staining to indicate apoptotic cells. To confirm the effects observed with CPD lesions, the molecular mimic of CPD, pTpT, was also tested in vitro and in vivo for its effect on cell cycle and apoptosis. RESULTS: The specific repair of 6-4PP lesions after UVB exposure resulted in a dramatic reduction in apoptosis. These findings suggested that 6-4PP lesions may be the primary inducer of UVB-induced apoptosis. Repair of CPD lesions (despite their relative abundance in the UV-damaged cell) had little effect on the induction of apoptosis. Supporting these findings, the molecular mimic of CPD, (dinucleotide pTpT) could mimic the effects of UVB on cell cycle arrest, but were ineffective to induce apoptosis. CONCLUSION: The primary response of the cell to UV-induced 6-4PP lesions is to trigger an apoptotic program whereas the response of the cell to CPD lesions appears to principally involve cell cycle arrest. These findings suggest that CPD and 6-4 PP may induce differential biological effects in the UV-damaged cell.


Assuntos
Apoptose , Dano ao DNA , Dímeros de Pirimidina/farmacologia , Raios Ultravioleta , Animais , Biópsia , Western Blotting , Ciclo Celular , Reparo do DNA , Desoxirribodipirimidina Fotoliase/química , Desoxirribodipirimidina Fotoliase/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Células Jurkat , Camundongos , Camundongos Endogâmicos C57BL , Dímeros de Pirimidina/metabolismo , Radioimunoensaio , Transfecção
15.
J Biol Chem ; 278(28): 25428-34, 2003 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-12690107

RESUMO

Proapoptotic gene transfer to promote death or to augment killing by DNA-damaging agents represents a promising strategy for cancer therapy. We have constructed an adenoviral Tet-Off trade mark vector with tightly controlled expression of Bid (Ad-Bid) (Clontech, Palo Alto, CA). Using the non-small cell lung cancer cell lines H460, H358, and A549, low dose Ad-Bid was shown to induce high levels of full-length Bid as well as caspase-3 and -9 activity. Although only a small fraction of Bid was processed to truncated Bid (a step inhibited by benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone), Ad-Bid gene transfer resulted in mitochondrial changes consistent with apoptosis (mitochondrial depolarization, cytochrome c release), DNA fragmentation, and a dramatic loss of cell viability. The proapoptotic effects of Ad-Bid were independent of p53 status and were augmented markedly by caspase-8 activators such as the DNA-damaging agent cisplatin. When Ad-Bid and cisplatin were used together, chemosensitivity was restored in p53-null H358 cells, increasing death from 35% following treatment with cisplatin and Ad-LacZ to >90% death with Ad-Bid and cisplatin (Ad-Bid alone induced 50% cell death under these conditions). Ad-Bid can induce apoptosis in malignant cells and enhance chemosensitivity in the absence of p53, suggesting this approach as a potential cancer therapy.


Assuntos
Adenoviridae/genética , Apoptose , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Transporte/biossíntese , Caspases/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteína Supressora de Tumor p53/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Dano ao DNA , Fragmentação do DNA , Citometria de Fluxo , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Potenciais da Membrana , Mitocôndrias/metabolismo , Fatores de Tempo , Células Tumorais Cultivadas
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