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1.
Nat Commun ; 10(1): 1107, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846683

RESUMO

Soil biota accounts for ~25% of global biodiversity and is vital to nutrient cycling and primary production. There is growing momentum to study total belowground biodiversity across large ecological scales to understand how habitat and soil properties shape belowground communities. Microbial and animal components of belowground communities follow divergent responses to soil properties and land use intensification; however, it is unclear whether this extends across heterogeneous ecosystems. Here, a national-scale metabarcoding analysis of 436 locations across 7 different temperate ecosystems shows that belowground animal and microbial (bacteria, archaea, fungi, and protists) richness follow divergent trends, whereas ß-diversity does not. Animal richness is governed by intensive land use and unaffected by soil properties, while microbial richness was driven by environmental properties across land uses. Our findings demonstrate that established divergent patterns of belowground microbial and animal diversity are consistent across heterogeneous land uses and are detectable using a standardised metabarcoding approach.


Assuntos
Biodiversidade , Ecossistema , Microbiologia do Solo , Solo , Animais , Biologia Computacional , Código de Barras de DNA Taxonômico , Microbiota/genética , País de Gales
2.
BJU Int ; 109(8): 1250-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21756282

RESUMO

OBJECTIVE: To resolve much debated issues surrounding p53 function, expression and mutation in renal cell carcinoma (RCC), we performed the first study to simultaneously determine p53/MDM2 expression, TP53 mutational status (in p53-positive patients) and outcome in RCC. PATIENTS AND METHODS: In total, 90 specimens obtained from patients with RCC, who were treated by radical nephrectomy, were analyzed by immunohistochemistry for p53 and MDM2 on a tissue microarray, and p53 was functionally and genetically analyzed in p53 positive samples. Outcome analysis was by the Kaplan-Meier method and univariate analysis was used to identify variables for subsequent multivariate analysis of correlations between clinical parameters and biomarker expression. RESULTS: Up-regulation of p53 in RCC is strongly linked with MDM2 up-regulation (P < 0.001). Increased coexpression of p53 and MDM2 identifies those patients with a significantly reduced disease-specific survival by univariate (P= 0.036) and Cox multiple regression analysis (P= 0.027; relative risk, 3.20). Functional (i.e. functional analysis of separated alleles in yeast) and genetic analysis of tumours with increased p53 expression shows that most patients (86%) retain wild-type p53. CONCLUSIONS: Coexpression of p53/MDM2 identifies a subset of patients with poor prognosis, despite all of them having organ-confined disease. Up-regulated p53 is typically wild-type and thus provides a mechanistic explanation for the association between p53 and MDM2 expression: up-regulated wild-type p53 likely promotes the observed MDM2 coexpression. The results obtained in the present study suggest that the p53 pathway is altered in a tissue/disease-specific manner and that therapeutic strategies targeting this pathway should be investigated to determine whether the tumour suppressive function of p53 can be rescued in RCC.


Assuntos
Carcinoma de Células Renais/genética , DNA de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica , Nefrectomia , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Progressão da Doença , Feminino , Genótipo , Humanos , Imuno-Histoquímica , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Proteínas Proto-Oncogênicas c-mdm2/biossíntese , Estudos Retrospectivos , Proteína Supressora de Tumor p53/biossíntese , Adulto Jovem
3.
Int J Cancer ; 123(1): 85-8, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18386815

RESUMO

X-box binding protein 1 (XBP-1) is stimulated by endoplasmic reticulum stress as part of the unfolded protein response (UPR), which can promote apoptosis or cell survival. Non-conventional splicing, stimulated during the UPR, converts mRNA for "unspliced" XBP-1U to "spliced" XBP-1S mRNA. XBP-1 mRNA is oestrogen-responsive, but XBP-1S confers oestrogen independence and anti-oestrogen resistance to breast cancer cell lines. We therefore evaluated XBP-1 mRNA splicing as a factor in response of breast cancer patients to endocrine treatment. XBP-1 isoforms were measured by quantitative RT-PCR in 100 primary breast cancer patients treated with adjuvant tamoxifen (including 30 ER alpha-negative cases). In ER alpha-positive cases, levels of XBP-1U mRNA correlated with ER alpha mRNA levels and were lower in grade 3 tumors. Higher levels of XBP-1U mRNA were significantly associated with breast cancer survival (Log-rank p = 0.002; Cox hazard ratio (HR) 0.2, p = 0.005), independent of grade, size, nodal status and progesterone receptor status. However, in the full cohort, higher ratios of XBP-1S/XBP-1U mRNA (indicating enhanced splicing) were associated with poor survival (Log-rank p = 0.03; Cox HR 2.3, p = 0.03) and related factors: ER alpha-negative status, progesterone receptor negative status, grade 3 tumors and greater proliferation. Significant associations with poor outcome were also seen for XBP-1 splicing in ER alpha-positive cases. Our findings, that XBP-1 isoforms are differently associated with outcome of endocrine therapy for patients, can be explained by higher levels of dominant-negative XBP-1U favouring apoptosis of tumor cells and higher levels of XBP-1S increasing tumor survival.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Dobramento de Proteína , Processamento de Proteína , Tamoxifeno/uso terapêutico , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Proteínas de Ligação a DNA/genética , Intervalo Livre de Doença , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Razão de Chances , Modelos de Riscos Proporcionais , RNA Mensageiro/metabolismo , Receptores de Progesterona/metabolismo , Fatores de Transcrição de Fator Regulador X , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição , Proteína 1 de Ligação a X-Box
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