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1.
Int J Mol Sci ; 20(19)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554290

RESUMO

Grape hyacinth (Muscari spp.) is a popular ornamental plant with bulbous flowers noted for their rich blue color. Muscari species have been thought to accumulate delphinidin and cyanidin rather than pelargonidin-type anthocyanins because their dihydroflavonol 4-reductase (DFR) does not efficiently reduce dihydrokaempferol. In our study, we clone a novel DFR gene from blue flowers of Muscari. aucheri. Quantitative real-time PCR (qRT-PCR) and anthocyanin analysis showed that the expression pattern of MaDFR had strong correlations with the accumulation of delphinidin, relatively weak correlations with cyanidin, and no correations with pelargonidin. However, in vitro enzymatic analysis revealed that the MaDFR enzyme can reduce all the three types of dihydroflavonols (dihydrokaempferol, dihydroquercetin, and dihydromyricetin), although it most preferred dihydromyricetin as a substrate to produce leucodelphinidin, the precursor of blue-hued delphinidin. This indicated that there may be other functional genes responsible for the loss of red pelargonidin-based pigments in Muscari. To further verify the substrate-specific selection domains of MaDFR, an assay of amino acid substitutions was conducted. The activity of MaDFR was not affected whenever the N135 or E146 site was mutated. However, when both of them were mutated, the catalytic activity of MaDFR was lost completely. The results suggest that both the N135 and E146 sites are essential for the activity of MaDFR. Additionally, the heterologous expression of MaDFR in tobacco (Nicotiana tabacum) resulted in increasing anthocyanin accumulation, leading to a darker flower color, which suggested that MaDFR was involved in color development in flowers. In summary, MaDFR has a high preference for dihydromyricetin, and it could be a powerful candidate gene for genetic engineering for blue flower colour modification. Our results also make a valuable contribution to understanding the basis of color variation in the genus Muscari.

2.
Int J Mol Sci ; 20(18)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31500111

RESUMO

Purple turnip Brassica rapa ssp. rapa is highly appreciated by consumers but the metabolites and molecular mechanisms underlying the root skin pigmentation remain open to study. Herein, we analyzed the anthocyanin composition in purple turnip (PT) and green turnip (GT) at five developmental stages. A total of 21 anthocyanins were detected and classified into the six major anthocynanin aglycones. Distinctly, PT contains 20 times higher levels of anthocyanins than GT, which explain the difference in the root skin pigmentation. We further sequenced the transcriptomes and analyzed the differentially expressed genes between the two turnips. We found that PT essentially diverts dihydroflavonols to the biosynthesis of anthocyanins over flavonols biosynthesis by strongly down-regulating one flavonol synthase gene, while strikingly up-regulating dihydroflavonol 4-reductase (DFR), anthocyanidin synthase and UDP-glucose: flavonoid-3-O-glucosyltransferase genes as compared to GT. Moreover, a nonsense mutation identified in the coding sequence of the DFR gene may lead to a nonfunctional protein, adding another hurdle to the accumulation of anthocyanin in GT. We also uncovered several key members of MYB, bHLH and WRKY families as the putative main drivers of transcriptional changes between the two turnips. Overall, this study provides new tools for modifying anthocyanin content and improving turnip nutritional quality.

3.
PLoS One ; 14(7): e0219161, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31339879

RESUMO

Ammonium pulse attributed to runoff of urban surface and agriculture following heavy rain is common in inland aquatic systems and can cause profoundly effects on the growth of macrophytes, especially when combined with low light. In this study, three patterns of NH4-N pulse (differing in magnitude and frequency) were applied to examine their effects on the growth of three submersed macrophytes, namely, Myriophyllum spicatum, Potamogeton maackianus, and Vallisneria natans, in terms of biomass, height, branch/ramet number, root length, leaf number, and total branch length under high and low light. Results showed that NH4-N pulse caused negative effects on the biomass of the submerged macrphytes even on the 13th day after releasing NH4-N pulse. The negative effects on M. spicatum were significantly greater than that on V. natans and P. maackianus. The effects of NH4-N pulse on specific species depended on the ammonium loading patterns. The negative effects of NH4-N pulse on P. maackianus were the strongest at high loading with low frequency, and on V. natans at moderate loading with moderate frequency. For M. spicatum, no significant differences were found among the three NH4-N pulse patterns. Low light availability did not significantly aggregate the negative effects of NH4-N pulse on the growth of the submersed macrophytes. Our study contributes to revealing the roles of NH4-N pulse on the growth of aquatic plants and its species specific effects on the dynamics of submerged macrophytes in lakes.

5.
Sci Rep ; 7(1): 8294, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28811648

RESUMO

Ecological processes are generally scale-dependent and there is little consensus about the relative importance of deterministic versus stochastic processes in driving patterns of biological diversity. We investigated how the relationship between functional dispersion and environmental gradients changes with spatial scale in subtropical freshwater lakes. The functional alpha and beta dispersions of all the tested traits were significantly under-dispersed across spatial scales and along environmental gradients. Results showed more functional similarity within communities in leaf dry mass content and flowering duration but less functional turnover among communities in all the tested traits at regional scales (Yunnan-Guizhou plateau and the middle and low reaches of the Yangtze River). The strengths and directions of environmental effects on the functional alpha and beta dispersions depended on the selected traits, diversity metrics and spatial scales. Surprisingly, broad-scale factors - elevation and water transparency - decreased the functional turnover for most traits along the gradients, whereas fine-scale factors - water depth - produced the opposite patterns along the gradient, depending on the trait selected. Our study highlights the dominant role of deterministic assembly processes in structuring the local functional composition and governing the spatial functional turnover of macrophyte communities across multiple spatial scales.


Assuntos
Biodiversidade , Clima , Ecossistema , Água Doce/microbiologia , Lagos/microbiologia , Meio Ambiente , Análise Espacial
6.
Chemosphere ; 184: 137-147, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28586654

RESUMO

SPE-UPLC-MS/MS was used to investigate the occurrence of 18 target antibiotics in the surface water of Poyang Lake over different seasons of 2014-2015. The maximum concentrations of sulfadiazine, oxytetracycline, and doxycycline were 56.2, 48.7, and 39.7 ng/L, respectively. Compared with those in the other lakes or surface waters, the surface water of Poyang Lake contained moderate or below-average levels of antibiotics. The significantly lower concentrations (P < 0.01) of roxithromycin in June 2015 likely resulted from the dilution effect of water flow during the flood season. Antibiotic concentrations were higher in site P3-1 than in other sites (P < 0.01), whereas those in other sites (P1-1, P2-1, P5-1, P6-1, P7-1, P13-1, P16-1, P17-1, P18-1) were not significantly different (P > 0.05). Given that tetracyclines and sulfonamides are common veterinary medicines, the high concentrations of oxytetracycline, doxycycline, and sulfadiazine in site P3-1 might be closely related to agricultural production in the surrounding areas. The risk assessment of the main antibiotic contaminants revealed that the majority of the risk quotients of the target antibiotics were below 0.01, thereby indicating the minimal risk of these antibiotics to organisms at three different trophic levels. Sulfadimidine and sulfadiazine were identified as the main antibiotics that contribute to ecological risk in Poyang Lake, and that the daphnid is the main model organism exposed to these risks. This study provides important data for antibiotic pollution control and environmental protection in the study area and enriches environmental monitoring data on a global scale.


Assuntos
Antibacterianos/análise , Monitoramento Ambiental , Lagos/química , Poluentes Químicos da Água/análise , China , Lagos/análise , Medição de Risco , Estações do Ano , Espectrometria de Massas em Tandem , Tetraciclinas/análise , Água
7.
Front Plant Sci ; 8: 965, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28642775

RESUMO

Anthocyanins are responsible for the different colors of ornamental plants. Grape hyacinth (Muscari armeniacum), a monocot plant with bulbous flowers, is popular for its fascinating blue color. In the present study, we functionally characterized an R2R3-MYB transcription factor gene MaAN2 from M. armeniacum. Our results indicated that MaAN2 participates in controlling anthocyanin biosynthesis. Sequence alignment and phylogenetic analysis suggested that MaAN2 belonged to the R2R3-MYB family AN2 subgroup. The anthocyanin accumulation of grape hyacinth flowers was positively correlated with the expression of MaAN2. And the transcriptional expression of MaAN2 was also consistent with that of M. armeniacum dihydroflavonol 4-reductase (MaDFR) and M. armeniacum anthocyanidin synthase (MaANS) in flowers. A dual luciferase transient expression assay indicated that when MaAN2 was co-inflitrated with Arabidopsis thaliana TRANSPARENT TESTA8 (AtTT8), it strongly activated the promoters of MaDFR and MaANS, but not the promoters of M. armeniacum chalcone synthase (MaCHS), M. armeniacum chalcone isomerase (MaCHI), and M. armeniacum flavanone 3-hydroxylase (MaF3H). Bimolecular fluorescence complementation assay confirmed that MaAN2 interacted with AtTT8 in vivo. The ectopic expression of MaAN2 in Nicotiana tabacum resulted in obvious red coloration of the leaves and much redder flowers. Almost all anthocyanin biosynthetic genes were remarkably upregulated in the leaves and flowers of the transgenic tobacco, and NtAn1a and NtAn1b (two basic helix-loop-helix anthocyanin regulatory genes) were highly expressed in the transformed leaves, compared to the empty vector transformants. Collectively, our results suggest that MaAN2 plays a role in anthocyanin biosynthesis.

8.
Molecules ; 22(5)2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28445423

RESUMO

Grape hyacinth (Muscari spp.) is a popular ornamental bulbous perennial famous for its blue flowers. To understand the chemical basis of the rich blue colors in this plant, anthocyanin profiles of six blue flowering grape hyacinths as well as one pink and one white cultivar were determined using high-performance liquid chromatography and mass spectrometry. Along with two known compounds, eight putative anthocyanins were identified in the tepals of grape hyacinth for the first time. The accumulation and distribution of anthocyanins in the plant showed significant cultivar and flower development specificity. Violet-blue flowers mainly contained simple delphinidin-type anthocyanins bearing one or two methyl-groups but no acyl groups, whereas white and pink flowers synthesised more complex pelargonidin/cyanidin-derivatives with acyl-moieties but no methyl-groups. The results partially reveal why solid blue, orange or red flowers are rare in this plant in nature. In addition, pelargonidin-type anthocyanins were found for the first time in the genus, bringing more opportunities in terms of breeding of flower color in grape hyacinth.


Assuntos
Antocianinas/isolamento & purificação , Asparagaceae/química , Flores/química , Extratos Vegetais/isolamento & purificação , Acilação , Antocianinas/química , Metilação , Extratos Vegetais/química , Especificidade da Espécie
9.
Environ Pollut ; 226: 154-162, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28431314

RESUMO

Metals can react with microcystin (MC), which is released from cyanobacterial blooms through various mechanisms; these reactions may mitigate the environmental and health risks of MCs but may also cause harm to aquatic ecosystems and humans. Several studies were conducted, including laboratory tests, ecological simulations, and a field investigation of Poyang Lake. The laboratory studies showed that Fe3+, Cu2+, and Pb2+ stimulated MC photodegradation under high light intensity at the water-sediment interface, which reduced the MC accumulation in the sediment. In the laboratory studies involving the addition of metal ions to lake sediment containing adsorbed MC, MC biodegradation was inhibited by supplementing with high levels of Fe3+, Cu2+, or Pb2+. Fe3+ and Pb2+ promoted MC accumulation in the hydrophyte Eichhornia crassipes at relatively low concentrations, but this effect decreased with increasing high metal concentrations. An ecological survey in Poyang Lake during the dry season demonstrated that high Fe levels can reduce MC accumulation in the sediment, which could be the result of Fe-mediated photodegradation. The results indicate that metals involved in MC transportation and degradation may play an important role in the environmental fate of MC.


Assuntos
Metais/toxicidade , Microcistinas/análise , Microbiologia da Água , Poluentes Químicos da Água/toxicidade , Adsorção , Biodegradação Ambiental , Cianobactérias/metabolismo , Lagos/química , Lagos/microbiologia , Metais/metabolismo , Fotólise , Estações do Ano , Poluentes Químicos da Água/análise
10.
J Hazard Mater ; 307: 350-8, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26826938

RESUMO

The uses of laccase in the degradation and removal of antibiotics have recently been reported because of the high efficiency and environmental friendliness of laccase. However, these removal studies mostly refer to a limited number of antibiotics. In this study, soil adsorption was introduced into the laccase-oxidation system to assist the simultaneous removal of 14 kinds of sulfonamide, tetracycline, and quinolone antibiotics, which differed in structures and chemical properties. The complementary effects of laccase-mediated oxidation and soil adsorption enabled the simultaneous removal. Removal characteristics were determined by a comprehensive consideration of the separate optimum conditions for laccase oxidation and soil adsorption removal experiments. With concentrations of laccase, syringaldehyde (SA), and soil of 0.5mg/mL, 0.5mmol/L, and 50g/L, respectively, and at pH 6 and 25°C, the removal rates of each antibiotic exceeded 70% in 15min and were close to 100% in 180min. Sulfonamide antibiotics (SAs) were removed mainly by laccase oxidation and quinolone antibiotics (QUs) mainly by soil adsorption. Tetracycline antibiotics (TCs) were removed by both treatments in the coupled system, but laccase oxidation dominated. Electrostatic adsorption was speculated to be one of the adsorption mechanisms in soil adsorption with QUs and TCs.


Assuntos
Antibacterianos/química , Lacase/química , Quinolonas/química , Poluentes do Solo/química , Sulfonamidas/química , Tetraciclinas/química , Adsorção , Oxirredução , Solo/química
11.
PLoS One ; 10(7): e0131630, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26167856

RESUMO

Trait-based approaches have been widely applied to investigate how community dynamics respond to environmental gradients. In this study, we applied a series of maximum entropy (maxent) models incorporating functional traits to unravel the processes governing macrophyte community structure along water depth gradient in a freshwater lake. We sampled 42 plots and 1513 individual plants, and measured 16 functional traits and abundance of 17 macrophyte species. Study results showed that maxent model can be highly robust (99.8%) in predicting the species relative abundance of macrophytes with observed community-weighted mean (CWM) traits as the constraints, while relative low (about 30%) with CWM traits fitted from water depth gradient as the constraints. The measured traits showed notably distinct importance in predicting species abundances, with lowest for perennial growth form and highest for leaf dry mass content. For tuber and leaf nitrogen content, there were significant shifts in their effects on species relative abundance from positive in shallow water to negative in deep water. This result suggests that macrophyte species with tuber organ and greater leaf nitrogen content would become more abundant in shallow water, but would become less abundant in deep water. Our study highlights how functional traits distributed across gradients provide a robust path towards predictive community ecology.


Assuntos
Ecossistema , Entropia , Lagos , Modelos Teóricos , Plantas/metabolismo , China , Especificidade da Espécie
12.
J Exp Bot ; 65(12): 3157-64, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24790110

RESUMO

Grape hyacinth (Muscari) is an important ornamental bulbous plant with an extraordinary blue colour. Muscari armeniacum, whose flowers can be naturally white, provides an opportunity to unravel the complex metabolic networks underlying certain biochemical traits, especially colour. A blue flower cDNA library of M. armeniacum and a white flower library of M. armeniacum f. album were used for transcriptome sequencing. A total of 89 926 uni-transcripts were isolated, 143 of which could be identified as putative homologues of colour-related genes in other species. Based on a comprehensive analysis relating colour compounds to gene expression profiles, the mechanism of colour biosynthesis was studied in M. armeniacum. Furthermore, a new hypothesis explaining the lack of colour phenotype of the grape hyacinth flower is proposed. Alteration of the substrate competition between flavonol synthase (FLS) and dihydroflavonol 4-reductase (DFR) may lead to elimination of blue pigmentation while the multishunt from the limited flux in the cyanidin (Cy) synthesis pathway seems to be the most likely reason for the colour change in the white flowers of M. armeniacum. Moreover, mass sequence data obtained by the deep sequencing of M. armeniacum and its white variant provided a platform for future function and molecular biological research on M. armeniacum.


Assuntos
Antocianinas/metabolismo , Flores , Regulação da Expressão Gênica de Plantas , Liliaceae , Pigmentação , Proteínas de Plantas/metabolismo , Transcriptoma , Antocianinas/genética , Flores/genética , Flores/metabolismo , Liliaceae/genética , Liliaceae/metabolismo , Fenótipo , Proteínas de Plantas/genética , Análise de Sequência de RNA
13.
Protoplasma ; 250(6): 1273-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23677687

RESUMO

The inflorescence of the broad-leafed grape hyacinth, Muscari latifolium, shows an interesting, two-tone appearance with the upper flowers being pale blue and the lower ones purple. To elucidate the mechanism of the differential color development, anatomical research was carried out and a cytological study of the colored protoplasts in which the shapes of the cells accumulating anthocyanin were observed by scanning electron microscopy. Next, vacuolar pH was recorded using a pH meter with a micro combination pH electrode, and the sap's metal-ion content was measured by inductively coupled plasma mass spectrometry. The anthocyanin and co-pigment composition was determined by high-performance liquid chromatography (HPLC). Chemical analyses reveal that the difference in metal-ion content of the two parts was not great. The vacuolar pHs of the upper and lower flowers were 5.91 and 5.84, respectively, with the difference being nonsignificant. HPLC results indicate that the dihydroflavonol and flavonol contents are also very similar in the two sorts of flower. However, the upper flowers contained only delphinidin, whereas the lower flowers also contained cyanidin. The total anthocyanin content in the lower flowers was 4.36 mg g(-1), which is approximately seven times higher than in the upper flowers, while the delphinidin content is four times higher. Quantitative real-time PCR analysis established that the two-tone flower was a result of different expressions of the F3'5'H, F3'H and DFR genes, and these lead to different amounts of anthocyanin.


Assuntos
Flores/anatomia & histologia , Flores/crescimento & desenvolvimento , Liliaceae/anatomia & histologia , Liliaceae/crescimento & desenvolvimento , Pigmentação , Antocianinas/metabolismo , Vias Biossintéticas/genética , Elementos , Flores/genética , Flores/ultraestrutura , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Concentração de Íons de Hidrogênio , Liliaceae/genética , Liliaceae/ultraestrutura , Fenótipo , Exsudatos de Plantas/metabolismo , Protoplastos/metabolismo
14.
Cell Cycle ; 12(9): 1385-94, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23574723

RESUMO

Colorectal cancer (CRC) is one of the leading cancer-related causes of death in the world. Recently, downregulation of microRNA-143 (miR-143) has been observed in CRC tissues. Here in this study, we found that miR-143 expression was downregulated both in CRC patients' blood samples and tumor specimens. MiR-143 expression levels were strongly correlated with clinical stages and lymph node metastasis. Furthermore, insulin-like growth factor-I receptor (IGF-IR), a known oncogene, was a novel direct target of miR-143, whose expression levels were inversely correlated with miR-143 expression in human CRC specimens. Overexpression of miR-143 inhibited cell proliferation, migration, tumor growth and angiogenesis and increased chemosensitivity to oxaliplatin treatment in an IGF-IR-dependent manner. Taken together, these results revealed that miR-143 levels in human blood and tumor tissues are associated with CRC cancer occurrence, metastasis and drug resistance, and miR-143 levels may be used as a new diagnostic marker and therapeutic target for CRC in the future.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , MicroRNAs/metabolismo , Neovascularização Patológica/genética , Compostos Organoplatínicos/uso terapêutico , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Nus , MicroRNAs/genética , Dados de Sequência Molecular , Neovascularização Patológica/tratamento farmacológico , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Receptor IGF Tipo 1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Isotopes Environ Health Stud ; 49(2): 188-96, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23473021

RESUMO

Based on the monthly δ(18)O value measured over a hydrology period in precipitation, runoff of five tributaries and the main lake of the Poyang Lake Basin, combined with hydrological and meteorological data, the characteristics of δ(18)O in precipitation (δ(18)OPPT) and runoff (δ(18)OSUR) are discussed. The δ(18)OPPT and δ(18)OSUR values range from-2.75 to-14.12 ‰ (annual mean value=-7.13 ‰ ) and from-2.30 to-8.56 ‰, respectively. The seasonal variation of δ(18)OPPT is controlled by the air mass circulation in this region, which is dominated by the Asian summer monsoon and the Siberian High during winter. The correlation between the wet seasonal averages of δ(18)OSUR in runoff of the rivers and δ(18)OPPT of precipitation at the corresponding stations shows that in the Poyang Lake catchment area the river water consists of 23% direct runoff (precipitation) and 77% base flow (shallow groundwater). This high proportion of groundwater in the river runoff points to the prevalence of wetland conditions in the Poyang Lake catchment during rainy season. Considering the oxygen isotopic composition of the main body of Poyang Lake, no isotopic enrichment relative to river inflow was found during the rainy season with maximum expansion of the lake. Thus, evaporation causing isotopic enrichment is a minor component of the lake water balance in the rainy period. During dry season, a slight isotopic enrichment has been observed, which suggests a certain evaporative loss of lake water in that period.


Assuntos
Monitoramento Ambiental/métodos , Água Doce/química , Isótopos de Oxigênio/análise , Chuva/química , Estações do Ano , Ciclo Hidrológico , China , Mudança Climática , Mapeamento Geográfico , Hidrologia , Lagos/química , Rios/química
16.
PLoS One ; 8(1): e54970, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23372805

RESUMO

BACKGROUND: The prognostic significance of p16 promoter hypermethylation in patients with non-small cell lung cancer (NSCLC) is still controversial. This analysis presents pooled estimates of the association to better elucidate whether p16 methylation has a prognostic role in NSCLC. METHODS: Relevant studies were identified by searching PubMed, Embase and Web of Science databases until June 2012. The association of p16 methylation with both overall survival (OS) and disease-free survival (DFS) was preformed. Studies were pooled and summary hazard ratios (HR) were calculated. Subgroup analyses, sensitivity analysis and publication bias were also conducted. RESULTS: A total of 18 studies containing 2432 patients met the inclusion criteria and had sufficient survival data for quantitative aggregation. The results showed that p16 methylation was an indicator of poor prognosis in NSCLC. The HR was 1.36 (95% CI: 1.08-1.73, I(2) = 56.7%) and 1.68 (95% CI: 1.12-2.52, I(2) = 38.7%) for OS and DFS, respectively. Subgroup analyses were carried out. The HRs of fresh and paraffin tissue were 1.50 (95% CI: 1.11-2.01) and 1.10 (95% CI: 0.77-1.57). The pooled HR was 1.40 (95% CI: 1.02-1.92) for methylation-specific PCR (MSP) and 1.26 (95% CI: 0.87-1.82) for quantitative MSP (Q-MSP). The combined HR of the 16 studies reporting NSCLC as a whole indicated that patients with p16 hypermethylation had poor prognosis. No significant association was found when adenocarcinoma subtype pooled. When seven studies on DFS were aggregated, the HR was 1.68 (95% CI: 1.12-2.52) without significant heterogeneity. Moreover, no obvious publication bias was detected on both OS and DFS. CONCLUSION: The meta-analysis findings support the hypothesis that p16 methylation is associated with OS and DFS in NSCLC patients. Large well-designed prospective studies are now needed to confirm the clinical utility of p16 methylation as an independent prognostic marker.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Epigênese Genética , Inativação Gênica , Genes p16 , Neoplasias Pulmonares/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Metilação de DNA , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Razão de Chances , Prognóstico , Regiões Promotoras Genéticas , Viés de Publicação
17.
PLoS One ; 7(3): e34100, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22457815

RESUMO

PURPOSE: The potential prognostic value of survivin in resected non-small cell lung carcinoma (NSCLC) is variably reported. The objective of this study was to conduct a systematic review of literatures evaluating survivin expression in resected NSCLC as a prognostic indicator. METHODS: Relevant literatures were identified using PubMed, EMBASE and Chinese Biomedicine Databases. We present the results of a meta-analysis of the association between survivin expression and overall survival (OS) in NSCLC patients. Studies were pooled and summary hazard ratios (HR) were calculated. Subgroup analyses and publication bias were also conducted. RESULTS: We performed a final analysis of 2703 patients from 28 evaluable studies. Combined HRs suggested that survivin overexpression had an unfavorable impact on NSCLC patients' survival with no evidence of any significant publication bias (HR = 2.03, 95%CI: 1.78-2.33, Egger's test, P = 0.24) and no severe heterogeneity between studies (I²  =  26.9%). Its effect also appeared significant when stratified according to the studies categorized by histological type, HR estimate, patient race, cutoff point (5%, 10%), detection methods and literature written language except for disease stage. Survivin was identified as a prognostic marker of advanced-stage NSCLC (HR = 1.93, 95%CI: 1.49-2.51), but not early-stage NSCLC (HR = 1.97, 95%CI: 0.76-5.14), in spite of the combined data being relatively small. CONCLUSION: This study shows that survivin expression appears to be a pejorative prognostic factor in terms of overall survival in surgically treated NSCLC. Large prospective studies are now needed to confirm the clinical utility of survivin as an independent prognostic marker.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/sangue , Proteínas Inibidoras de Apoptose/sangue , Neoplasias Pulmonares/sangue , Humanos , Prognóstico , Survivina
18.
PLoS One ; 7(3): e32425, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22403658

RESUMO

BACKGROUND AND OBJECTIVES: N-Acetyltransferase (NAT) 2 is an important enzyme involved in the metabolism of different xenobiotics, including potential carcinogens, whose phenotypes were reported to be related to individual susceptibility to colorectal cancer (CRC). However, the results remain conflicting. To assess the relationship between NAT2 phenotypes and CRC risk, we performed this meta-analysis. METHODS: A comprehensive literature search was conducted to identify all case-control or cohort studies of NAT2 acetylator status on the susceptibility of CRC by searching of PubMed and EMBASE, up to May 20, 2011. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association. RESULTS: A total of over 40,000 subjects from 40 published literatures were identified by searching the databases. No significantly elevated CRC risk in individuals with NAT2 slow acetylators compared with fast acetylators was found when all studies pooled (OR = 0.95, 95% CI: 0.87-1.04, I(2) = 52.6%). While three studies contributed to the source of heterogeneity were removed, there was still null result observed (OR = 0.96, 95% CI: 0.90-1.03, P = 0.17 for heterogeneity, I(2) = 17.8%). In addition, we failed to detect any associations in the stratified analyses by race, sex, source of controls, smoking status, genotyping methods or tumor localization. No publication bias was observed in this study. CONCLUSIONS: This meta-analysis suggests that the NAT2 phenotypes may not be associated with colorectal cancer development.


Assuntos
Arilamina N-Acetiltransferase/metabolismo , Neoplasias Colorretais/enzimologia , Acetilação , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Fenótipo , Viés de Publicação , Risco
19.
Clin Lung Cancer ; 13(3): 188-95, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22133292

RESUMO

BACKGROUND: The role of cell-cycle protein cyclin D1 in lung cancer remains controversial. To clarify its impact on survival in non-small-cell lung cancer (NSCLC), we performed a meta-analysis on the currently available medial literature to quantitatively assess its role on survival of NSCLC according to cyclin D1 status. METHOD: Published studies that investigated the association between cyclin D1 expression and NSCLC survival were identified. Meta-analysis was performed by using a DerSimonian-Laird model. Funnel plot was used to investigate publication bias and sources of heterogeneity were identified by using meta-regression analysis. RESULT: A total of 24 studies with 2731 patients were evaluable for this meta-analysis. No statistical significance was found that cyclin D1 expression was associated with poor prognosis in NSCLC (hazard ratio 1.08 [95% CI, 0.80-1.45]) without publication bias found. But there was significant heterogeneity present; meta-regression analysis was used to explore the sources of heterogeneity and revealed that the outcome of analysis was influenced by cutoff values and ethnicity. No difference between positive and negative studies on study quality assessment was present. CONCLUSION: The cyclin D1 expression is unlikely to be useful as a prognostic marker for NSCLC in clinical practice from current evidence. The conclusion should be confirmed by a large well-designed prospective study.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Ciclina D/metabolismo , Neoplasias Pulmonares/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Ciclina D/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/mortalidade , Variações Dependentes do Observador , Prognóstico , Análise de Sobrevida
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