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1.
Prev Sci ; 24(6): 1187-1197, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37083924

RESUMO

Co-regulation is a relatively new theoretical framework for interventions that connects developmental science to adolescent needs and provides strategies that can be applied across contexts. It also has value in shifting the focus of interventions to the role of relationships and interactions with caring adults, as well as supportive environments. This framework may be particularly salient for older youth with foster care experience whose relationships with adults and availability of developmental supports are disrupted. To understand how co-regulation aligns with current understanding of needs and supports for this population, we conducted a scoping review that involved systematically searching four databases, coding and charting relevant information, and actively engaging expert consultants and other stakeholders. Across 46 primarily descriptive articles, co-regulation was discussed most often in relation to relationships, as expected (89% of articles). Despite theoretical and empirical evidence of the benefits of supportive environments and intentional day-to-day interactions in promoting developmental skills and competencies, these two domains of co-regulation were referenced much less (39% and 28%, respectively). Results highlight opportunities for co-regulation supports that can be provided to older youth with foster care experience by caring adults and near-aged peers in a wide range of roles. Notable limitations in the literature were identified in applying co-regulation within the context of employment and career readiness, healthy relationships, and teen parenting. Also under-researched is the role of adult self-regulation skills and co-regulation approaches for youth from diverse backgrounds, including those who identify as LGBTQ or have disabilities. Considerations for practice and future research are provided.


Assuntos
Regulação Emocional , Emprego , Adolescente , Adulto , Humanos , Bases de Dados Factuais , Poder Familiar , Grupo Associado , Cuidados no Lar de Adoção
2.
BMJ Open ; 11(2): e042953, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632752

RESUMO

INTRODUCTION: Survival in men diagnosed with de novo synchronous metastatic prostate cancer has increased following the use of upfront systemic treatment, using chemotherapy and other novel androgen receptor targeted agents, in addition to standard androgen deprivation therapy (ADT). Local cytoreductive and metastasis-directed interventions are hypothesised to confer additional survival benefit. In this setting, IP2-ATLANTA will explore progression-free survival (PFS) outcomes with the addition of sequential multimodal local and metastasis-directed treatments compared with standard care alone. METHODS: A phase II, prospective, multicentre, three-arm randomised controlled trial incorporating an embedded feasibility pilot. All men with new histologically diagnosed, hormone-sensitive, metastatic prostate cancer, within 4 months of commencing ADT and of performance status 0 to 2 are eligible. Patients will be randomised to Control (standard of care (SOC)) OR Intervention 1 (minimally invasive ablative therapy to prostate±pelvic lymph node dissection (PLND)) OR Intervention 2 (cytoreductive radical prostatectomy±PLND OR prostate radiotherapy±pelvic lymph node radiotherapy (PLNRT)). Metastatic burden will be prespecified using the Chemohormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease (CHAARTED) definition. Men with low burden disease in intervention arms are eligible for metastasis-directed therapy, in the form of stereotactic ablative body radiotherapy (SABR) or surgery. Standard systemic therapy will be administered in all arms with ADT±upfront systemic chemotherapy or androgen receptor agents. Patients will be followed-up for a minimum of 2 years. PRIMARY OUTCOME: PFS. Secondary outcomes include predictive factors for PFS and overall survival; urinary, sexual and rectal side effects. Embedded feasibility sample size is 80, with 918 patients required in the main phase II component. Study recruitment commenced in April 2019, with planned follow-up completed by April 2024. ETHICS AND DISSEMINATION: Approved by the Health Research Authority (HRA) Research Ethics Committee Wales-5 (19/WA0005). Study results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03763253; ISCRTN58401737.


Assuntos
Antagonistas de Androgênios , Neoplasias da Próstata , Algoritmos , Antagonistas de Androgênios/uso terapêutico , Ensaios Clínicos Fase II como Assunto , Humanos , Masculino , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Neoplasias da Próstata/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , País de Gales
3.
Lancet ; 396(10260): 1413-1421, 2020 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-33002429

RESUMO

BACKGROUND: The optimal timing of radiotherapy after radical prostatectomy for prostate cancer is uncertain. We aimed to compare the efficacy and safety of adjuvant radiotherapy versus an observation policy with salvage radiotherapy for prostate-specific antigen (PSA) biochemical progression. METHODS: We did a randomised controlled trial enrolling patients with at least one risk factor (pathological T-stage 3 or 4, Gleason score of 7-10, positive margins, or preoperative PSA ≥10 ng/mL) for biochemical progression after radical prostatectomy (RADICALS-RT). The study took place in trial-accredited centres in Canada, Denmark, Ireland, and the UK. Patients were randomly assigned in a 1:1 ratio to adjuvant radiotherapy or an observation policy with salvage radiotherapy for PSA biochemical progression (PSA ≥0·1 ng/mL or three consecutive rises). Masking was not deemed feasible. Stratification factors were Gleason score, margin status, planned radiotherapy schedule (52·5 Gy in 20 fractions or 66 Gy in 33 fractions), and centre. The primary outcome measure was freedom from distant metastases, designed with 80% power to detect an improvement from 90% with salvage radiotherapy (control) to 95% at 10 years with adjuvant radiotherapy. We report on biochemical progression-free survival, freedom from non-protocol hormone therapy, safety, and patient-reported outcomes. Standard survival analysis methods were used. A hazard ratio (HR) of less than 1 favoured adjuvant radiotherapy. This study is registered with ClinicalTrials.gov, NCT00541047. FINDINGS: Between Nov 22, 2007, and Dec 30, 2016, 1396 patients were randomly assigned, 699 (50%) to salvage radiotherapy and 697 (50%) to adjuvant radiotherapy. Allocated groups were balanced with a median age of 65 years (IQR 60-68). Median follow-up was 4·9 years (IQR 3·0-6·1). 649 (93%) of 697 participants in the adjuvant radiotherapy group reported radiotherapy within 6 months; 228 (33%) of 699 in the salvage radiotherapy group reported radiotherapy within 8 years after randomisation. With 169 events, 5-year biochemical progression-free survival was 85% for those in the adjuvant radiotherapy group and 88% for those in the salvage radiotherapy group (HR 1·10, 95% CI 0·81-1·49; p=0·56). Freedom from non-protocol hormone therapy at 5 years was 93% for those in the adjuvant radiotherapy group versus 92% for those in the salvage radiotherapy group (HR 0·88, 95% CI 0·58-1·33; p=0·53). Self-reported urinary incontinence was worse at 1 year for those in the adjuvant radiotherapy group (mean score 4·8 vs 4·0; p=0·0023). Grade 3-4 urethral stricture within 2 years was reported in 6% of individuals in the adjuvant radiotherapy group versus 4% in the salvage radiotherapy group (p=0·020). INTERPRETATION: These initial results do not support routine administration of adjuvant radiotherapy after radical prostatectomy. Adjuvant radiotherapy increases the risk of urinary morbidity. An observation policy with salvage radiotherapy for PSA biochemical progression should be the current standard after radical prostatectomy. FUNDING: Cancer Research UK, MRC Clinical Trials Unit, and Canadian Cancer Society.


Assuntos
Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Prostatectomia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Adenocarcinoma/patologia , Idoso , Biomarcadores Tumorais/sangue , Intervalo Livre de Doença , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Modelos de Riscos Proporcionais , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Radioterapia Adjuvante , Terapia de Salvação , Análise de Sobrevida , Fatores de Tempo
4.
Int J Radiat Oncol Biol Phys ; 106(3): 525-533, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610249

RESUMO

PURPOSE: Whole pelvis radiation therapy (WPRT) may improve clinical outcomes over prostate-only radiation therapy (PORT) in high-risk prostate cancer patients by sterilization of micrometastatic nodal disease, provided there is optimal control of the primary site. METHODS AND MATERIALS: A prospective multicenter cohort study of eligible patients (stage ≥T2c, Gleason score ≥7 or presenting prostate-specific antigen ≥10) treated between 2009 and 2013 were enrolled in a United Kingdom national protocol delivering combined external beam radiation therapy and high-dose-rate brachytherapy. Centers elected to deliver WPRT, 46 Gy in 23 fractions or PORT 37.5 Gy in 15 fractions with 15 Gy single dose high-dose-rate brachytherapy. The primary endpoint was biochemical progression-free survival (bPFS). Secondary endpoints were overall survival, genitourinary, and gastrointestinal toxicity. This was not a randomized comparison and was subject to bias; the findings are therefore hypothesis generating, but not conclusive. RESULTS: Eight hundred and twelve patients were entered; 401 received WPRT and 411 received PORT. With a median follow-up of 4.7 years, 5-year bPFS rates for WPRT versus PORT arms were 89% versus 81% (P = .007) for all patients and 84% versus 77% (P = .001) for high-risk patients. Differences in bPFS remained significant after accounting for Gleason score, presenting prostate-specific antigen, T stage, and androgen deprivation therapy duration as covariates. There was no difference in overall survival. The overall post treatment toxicities across both cohorts were low with no greater than 1.5% of ≥grade 3 toxicities at any follow-up time point. WPRT increased both prevalence and cumulative incidence of acute genitourinary toxicity (P = .004) and acute gastrointestinal toxicity (P = .003). No difference in late radiation toxicity was observed. CONCLUSIONS: A significant improvement in 5-year bPFS was seen in intermediate and high-risk prostate cancer treated with WPRT compared with PORT in a combined external beam radiation therapy and brachytherapy schedule with no increase in late radiation toxicity.


Assuntos
Braquiterapia/métodos , Micrometástase de Neoplasia/radioterapia , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/uso terapêutico , Braquiterapia/efeitos adversos , Braquiterapia/estatística & dados numéricos , Estudos de Coortes , Bases de Dados Factuais , Fracionamento da Dose de Radiação , Seguimentos , Humanos , Calicreínas/sangue , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Intervalo Livre de Progressão , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Radioterapia Conformacional/estatística & dados numéricos , Radioterapia de Intensidade Modulada/estatística & dados numéricos , Reino Unido
5.
Mol Cell ; 75(2): 310-323.e8, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31104896

RESUMO

During gene expression, RNA export factors are mainly known for driving nucleo-cytoplasmic transport. While early studies suggested that the exon junction complex (EJC) provides a binding platform for them, subsequent work proposed that they are only recruited by the cap binding complex to the 5' end of RNAs, as part of TREX. Using iCLIP, we show that the export receptor Nxf1 and two TREX subunits, Alyref and Chtop, are recruited to the whole mRNA co-transcriptionally via splicing but before 3' end processing. Consequently, Alyref alters splicing decisions and Chtop regulates alternative polyadenylation. Alyref is recruited to the 5' end of RNAs by CBC, and our data reveal subsequent binding to RNAs near EJCs. We demonstrate that eIF4A3 stimulates Alyref deposition not only on spliced RNAs close to EJC sites but also on single-exon transcripts. Our study reveals mechanistic insights into the co-transcriptional recruitment of mRNA export factors and how this shapes the human transcriptome.


Assuntos
RNA Helicases DEAD-box/genética , Fator de Iniciação 4A em Eucariotos/genética , Proteínas Nucleares/genética , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Transcrição Gênica , Transporte Ativo do Núcleo Celular/genética , Sítios de Ligação , RNA Helicases DEAD-box/química , Fator de Iniciação 4A em Eucariotos/química , Éxons/genética , Regulação da Expressão Gênica/genética , Humanos , Proteínas Nucleares/química , Proteínas de Transporte Nucleocitoplasmático/química , Poliadenilação , Transporte de RNA/genética , RNA Mensageiro/química , RNA Mensageiro/genética , Proteínas de Ligação a RNA/química , Fatores de Transcrição/química , Transcriptoma/genética
6.
Sci Rep ; 8(1): 13827, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30218090

RESUMO

N6-methyladenosine (m6A) is the most abundant internal modification of eukaryotic mRNA. This modification has previously been shown to alter the export kinetics for mRNAs though the molecular details surrounding this phenomenon remain poorly understood. Recruitment of the TREX mRNA export complex to mRNA is driven by transcription, 5' capping and pre-mRNA splicing. Here we identify a fourth mechanism in human cells driving the association of TREX with mRNA involving the m6A methylase complex. We show that the m6A complex recruits TREX to m6A modified mRNAs and this process is essential for their efficient export. TREX also stimulates recruitment of the m6A reader protein YTHDC1 to the mRNA and the m6A complex influences the interaction of TREX with YTHDC1. Together our studies reveal a key role for TREX in the export of m6A modified mRNAs.


Assuntos
Adenosina/análogos & derivados , Exodesoxirribonucleases/metabolismo , Fosfoproteínas/metabolismo , Transporte de RNA/fisiologia , Transporte Ativo do Núcleo Celular , Adenosina/metabolismo , Adenosina/fisiologia , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Exodesoxirribonucleases/fisiologia , Células HEK293 , Humanos , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Fosfoproteínas/fisiologia , Splicing de RNA/fisiologia , Fatores de Processamento de RNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo
7.
Biochem J ; 473(19): 2911-35, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27679854

RESUMO

TRanscription and EXport (TREX) is a conserved multisubunit complex essential for embryogenesis, organogenesis and cellular differentiation throughout life. By linking transcription, mRNA processing and export together, it exerts a physiologically vital role in the gene expression pathway. In addition, this complex prevents DNA damage and regulates the cell cycle by ensuring optimal gene expression. As the extent of TREX activity in viral infections, amyotrophic lateral sclerosis and cancer emerges, the need for a greater understanding of TREX function becomes evident. A complete elucidation of the composition, function and interactions of the complex will provide the framework for understanding the molecular basis for a variety of diseases. This review details the known composition of TREX, how it is regulated and its cellular functions with an emphasis on mammalian systems.


Assuntos
Expressão Gênica , Fatores de Transcrição/fisiologia , Transporte Biológico , Dano ao DNA , Humanos , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
Future Oncol ; 10(2): 219-31, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24490608

RESUMO

AIMS: The aim of this article was to evaluate afatinib (BIBW 2992), an ErbB family blocker, and nintedanib (BIBF 1120), a triple angiokinase inhibitor, in castration-resistant prostate cancer patients. PATIENTS & METHODS: Patients were randomized to receive nintedanib (250 mg twice daily), afatinib (40 mg once daily [q.d.]), or alternating sequential 7-day nintedanib (250 mg twice daily) and afatinib (70 mg q.d. [Combi70]), which was reduced to 40 mg q.d. (Combi40) due to adverse events. The primary end point was progression-free rate at 12 weeks. RESULTS: Of the 85 patients treated 46, 20, 16 and three received nintedanib, afatinib, Combi40 and Combi70, respectively. At 12 weeks, the progression-free rate was 26% (seven out of 27 patients) for nintedanib, and 0% for afatinib and Combi40 groups. Two patients had a ≥50% decline in PSA (nintedanib and the Combi40 groups). The most common drug-related adverse events were diarrhea, nausea, vomiting and lethargy. CONCLUSION: Nintedanib and/or afatinib demonstrated limited anti-tumor activity in unselected advanced castration-resistant prostate cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Afatinib , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Humanos , Indóis/administração & dosagem , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias de Próstata Resistentes à Castração/patologia , Quinazolinas/administração & dosagem , Resultado do Tratamento
9.
BJU Int ; 112(7): 885-97, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24000900

RESUMO

• To review the published data on predisposing risk factors for cancer treatment-induced haemorrhagic cystitis (HC) and the evidence for the different preventive and therapeutic measures that have been used in order to help clinicians optimally define and manage this potentially serious condition. • Despite recognition that HC can be a significant complication of cancer treatment, there is currently a lack of UK-led guidelines available on how it should optimally be defined and managed. • A systematic literature review was undertaken to evaluate the evidence for preventative measures and treatment options in the management of cancer treatment-induced HC. • There is a wide range of reported incidence due to several factors including variability in study design and quality, the type of causal agent, the grading of bleeding, and discrepancies in definition criteria. • The most frequently reported causal factors are radiotherapy to the pelvic area, where HC has been reported in up to 20% of patients, and treatment with cyclophosphamide and bacillus Calmette-Guérin, where the incidence has been reported as up to 30%. • Mesna (2-mercaptoethane sodium sulphonate), hyperhydration and bladder irrigation have been the most frequently used prophylactic measures to prevent treatment-related cystitis, but are not always effective. • Cranberry juice is widely cited as a preventative measure and sodium pentosanpolysulphate as a treatment, although the evidence for both is very limited. • The best evidence exists for intravesical hyaluronic acid as an effective preventative and active treatment, and for hyperbaric oxygen as an equally effective treatment option. • The lack of robust data and variability in treatment strategies used highlights the need for further research, as well as best practice guidance and consensus on the management of HC.


Assuntos
Antineoplásicos/efeitos adversos , Cistite/etiologia , Cistite/terapia , Hemorragia/etiologia , Hemorragia/terapia , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Cistite/induzido quimicamente , Hemorragia/induzido quimicamente , Humanos , Incidência , Radioterapia/efeitos adversos
10.
BMC Genet ; 13: 80, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22963203

RESUMO

BACKGROUND: The various steps of mRNP biogenesis (transcription, processing and export) are interconnected. It has been shown that the transcription machinery plays a pivotal role in mRNP assembly, since several mRNA export factors are recruited during transcription and physically interact with components of the transcription machinery. Although the shuttling DEAD-box protein Dbp5p is concentrated on the cytoplasmic fibrils of the NPC, previous studies demonstrated that it interacts physically and genetically with factors involved in transcription initiation. RESULTS: We investigated the effect of mutations affecting various components of the transcription initiation apparatus on the phenotypes of mRNA export mutant strains. Our results show that growth and mRNA export defects of dbp5 and mex67 mutant strains can be suppressed by mutation of specific transcription initiation components, but suppression was not observed for mutants acting in the very first steps of the pre-initiation complex (PIC) formation. CONCLUSIONS: Our results indicate that mere reduction in the amount of mRNP produced is not sufficient to suppress the defects caused by a defective mRNA export factor. Suppression occurs only with mutants affecting events within a narrow window of the mRNP biogenesis process. We propose that reducing the speed with which transcription converts from initiation and promoter clearance to elongation may have a positive effect on mRNP formation by permitting more effective recruitment of partially-functional mRNP proteins to the nascent mRNP.


Assuntos
Ribonucleoproteínas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Transporte Ativo do Núcleo Celular , Alelos , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Mutação , Poro Nuclear/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética
11.
Cancer Immunol Immunother ; 61(11): 2161-70, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22729556

RESUMO

We report on the immunogenicity and clinical effects in a phase I/II dose escalation trial of a DNA fusion vaccine in patients with prostate cancer. The vaccine encodes a domain (DOM) from fragment C of tetanus toxin linked to an HLA-A2-binding epitope from prostate-specific membrane antigen (PSMA), PSMA(27-35). We evaluated the effect of intramuscular vaccination without or with electroporation (EP) on vaccine potency. Thirty-two HLA-A2(+) patients were vaccinated and monitored for immune and clinical responses for a follow-up period of 72 weeks. At week 24, cross-over to the immunologically more effective delivery modality was permitted; this was shown to be with EP based on early antibody data, and subsequently, 13/15 patients crossed to the +EP arm. Thirty-two HLA-A2(-) control patients were assessed for time to next treatment and overall survival. Vaccination was safe and well tolerated. The vaccine induced DOM-specific CD4(+) and PSMA(27)-specific CD8(+) T cells, which were detectable at significant levels above baseline at the end of the study (p = 0.0223 and p = 0.00248, respectively). Of 30 patients, 29 had a measurable CD4(+) T-cell response and PSMA(27)-specific CD8(+) T cells were detected in 16/30 patients, with or without EP. At week 24, before cross-over, both delivery methods led to increased CD4(+) and CD8(+) vaccine-specific T cells with a trend to a greater effect with EP. PSA doubling time increased significantly from 11.97 months pre-treatment to 16.82 months over the 72-week follow-up (p = 0.0417), with no clear differential effect of EP. The high frequency of immunological responses to DOM-PSMA(27) vaccination and the clinical effects are sufficiently promising to warrant further, randomized testing.


Assuntos
Antígenos de Superfície/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/administração & dosagem , Glutamato Carboxipeptidase II/uso terapêutico , Ativação Linfocitária/imunologia , Fragmentos de Peptídeos/uso terapêutico , Neoplasias da Próstata/terapia , Toxina Tetânica/uso terapêutico , Vacinas de DNA/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Fusão Gênica Artificial , Linfócitos T CD4-Positivos , Vacinas Anticâncer/imunologia , Eletroporação , Antígeno HLA-A2/análise , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/mortalidade , Vacinas de DNA/imunologia
12.
RNA ; 15(10): 1917-28, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19703940

RESUMO

With no known exceptions, every published microarray study to determine differential mRNA levels in eukaryotes used RNA extracted from whole cells. It is assumed that the use of whole cell RNA in microarray gene expression analysis provides a legitimate profile of steady-state mRNA. Standard labeling methods and the prevailing dogma that mRNA resides almost exclusively in the cytoplasm has led to the long-standing belief that the nuclear RNA contribution is negligible. We report that unadulterated cytoplasmic RNA uncovers differentially expressed mRNAs that otherwise would not have been detected when using whole cell RNA and that the inclusion of nuclear RNA has a large impact on whole cell gene expression microarray results by distorting the mRNA profile to the extent that a substantial number of false positives are generated. We conclude that to produce a valid profile of the steady-state mRNA population, the nuclear component must be excluded, and to arrive at a more realistic view of a cell's gene expression profile, the nuclear and cytoplasmic RNA fractions should be analyzed separately.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Animais , Western Blotting , Linhagem Celular , Perfilação da Expressão Gênica , Humanos , Camundongos , Reação em Cadeia da Polimerase
13.
Genetics ; 179(4): 1945-55, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18689878

RESUMO

Coordination of the multiple steps of mRNA biogenesis helps to ensure proper regulation of gene expression. The Saccharomyces cerevisiae DEAD-box protein Rat8p/Dbp5p is an essential mRNA export factor that functions at the nuclear pore complex (NPC) where it is thought to remodel mRNA/protein complexes during mRNA export. Rat8p also functions in translation termination and has been implicated in functioning during early transcription. We conducted a synthetic genetic array analysis (SGA) using a strain harboring the temperature-sensitive rat8-2 allele. Although RAT8 had been shown to interact genetically with >15 other genes, we identified >40 additional genes whose disruption in a rat8-2 background causes synthetic lethality or dramatically reduced growth. Included were five that encode components of P-bodies, sites of cytoplasmic mRNA turnover and storage. Wild-type Rat8p localizes to NPCs and diffusely throughout the cell but rat8-2p localized to cytoplasmic granules at nonpermissive temperature that are distinct from P-bodies. In some genetic backgrounds, these granules also contain poly(A)-binding protein, Pab1p, and additional mRNA export factors. Although these foci are distinct from P-bodies, the two merge under heat-stress conditions. We suggest that these granules reflect defective mRNP remodeling during mRNA export and during cytoplasmic mRNA metabolism.


Assuntos
RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Genes Fúngicos , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Alelos , Citoplasma/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Sintéticos , Poro Nuclear/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Polirribossomos/metabolismo , Saccharomyces cerevisiae/metabolismo
14.
Cancer Res ; 67(24): 11612-20, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18089790

RESUMO

MicroRNAs (miRNAs) are a new class of short noncoding regulatory RNAs (18-25 nucleotides) that are involved in diverse developmental and pathologic processes. Altered miRNA expression has been associated with several types of human cancer. However, most studies did not establish whether miRNA expression changes occurred within cells undergoing malignant transformation. To obtain insight into miRNA deregulation in breast cancer, we implemented an in situ hybridization (ISH) method to reveal the spatial distribution of miRNA expression in archived formalin-fixed, paraffin-embedded specimens representing normal and tumor tissue from >100 patient cases. Here, we report that expression of miR-145 and miR-205 was restricted to the myoepithelial/basal cell compartment of normal mammary ducts and lobules, whereas their accumulation was reduced or completely eliminated in matching tumor specimens. Conversely, expression of other miRNAs was detected at varying levels predominantly within luminal epithelial cells in normal tissue; expression of miR-21 was frequently increased, whereas that of let-7a was decreased in malignant cells. We also analyzed the association of miRNA expression with that of epithelial markers; prognostic indicators such as estrogen receptor, progesterone receptor, and HER2; as well as clinical outcome data. This ISH approach provides a more direct and informative assessment of how altered miRNA expression contributes to breast carcinogenesis compared with miRNA expression profiling in gross tissue biopsies. Most significantly, early manifestation of altered miR-145 expression in atypical hyperplasia and carcinoma in situ lesions suggests that this miRNA may have a potential clinical application as a novel biomarker for early detection.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Células Epiteliais/patologia , Células Epiteliais/fisiologia , Feminino , Humanos , Hibridização In Situ , Análise de Sequência com Séries de Oligonucleotídeos
15.
Mol Cell Biol ; 22(18): 6441-57, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12192043

RESUMO

In a screen to identify genes required for mRNA export in Saccharomyces cerevisiae, we isolated an allele of poly(A) polymerase (PAP1) and novel alleles encoding several other 3' processing factors. Many newly isolated and some previously described mutants (rna14-48, rna14-49, rna14-64, rna15-58, and pcf11-1 strains) are defective in polymerase II (Pol II) termination but, interestingly, retain the ability to polyadenylate these improperly processed transcripts at the nonpermissive temperature. Deletion of the cis-acting sequences required to couple 3' processing and termination also produces transcripts that fail to exit the nucleus, suggesting that all of these processes (cleavage, termination, and export) are coupled. We also find that several but not all mRNA export mutants produce improperly 3' processed transcripts at the nonpermissive temperature. 3' maturation defects in mRNA export mutants include improper Pol II termination and/or the previously characterized hyperpolyadenylation of transcripts. Importantly, not all mRNA export mutants have defects in 3' processing. The similarity of the phenotypes of some mRNA export mutants and 3' processing mutants indicates that some factors from each process may mechanistically interact to couple mRNA processing and export. Consistent with this assumption, we present evidence that Xpo1p interacts in vivo with several 3' processing factors and that the addition of recombinant Xpo1p to in vitro processing reaction mixtures stimulates 3' maturation. Of the core 3' processing factors tested (Rna14p, Rna15p, Pcf11p, Hrp1p, Fip1p, and Cft1p), only Hrp1p shuttles. Overexpression of Rat8p/Dbp5p suppresses both 3' processing and mRNA export defects found in xpo1-1 cells.


Assuntos
Carioferinas/metabolismo , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Alelos , Transporte Biológico , Núcleo Celular/metabolismo , Citometria de Fluxo , Proteínas Fúngicas/metabolismo , Deleção de Genes , Proteínas de Fluorescência Verde , Proteínas Luminescentes/metabolismo , Mutação , Proteínas Nucleares/metabolismo , Fases de Leitura Aberta , Proteínas Associadas a Pancreatite , Polinucleotídeo Adenililtransferase/metabolismo , RNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Recombinação Genética , Saccharomyces cerevisiae/metabolismo , Temperatura , Transcrição Gênica , Técnicas do Sistema de Duplo-Híbrido , Fatores de Poliadenilação e Clivagem de mRNA , Proteína Exportina 1
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