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1.
PLoS One ; 19(3): e0300562, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38498398

RESUMEN

α-klotho is an anti-aging protein. The correlation between smoking, smoking cessation and serum α-klotho levels remains controversial. The aim of this study was to investigate the association between smoking, smoking cessation and serum α-klotho levels. This cross-sectional study finally included 4877 participants, aged 40-79 years, who participated in the National Health and Nutrition Examination Survey studies from 2013 to 2016. Of these, 2312 (47.4%) were men and 894 (18.3%) were current smokers, and the mean age of the participants was 57.8±10.7 years. Multivariate linear regression modeling was used to assess the association between smoking, smoking cessation and serum α-klotho levels. After adjustment for multiple confounders, this study observed that smoking was negatively associated with serum α-klotho levels (ß: -58.3; 95% confidence interval CI: -82.0 to -34.6; p<0.001), whereas smoking cessation was positively associated with serum α-klotho levels (ß: 52.3; 95% CI: 24.1 to 80.6; p<0.001). In subgroup and interaction analyses, p-value for the interaction between smoking and race on serum klotho levels was found to be less than 0.001. The correlation between smoking, smoking cessation and serum α-klotho levels remained stable after propensity score matching (ß: -54.1; 95% CI: -81.5 to -26.7; p<0.001, ß: 54.8; 95% CI: 24.2 to 85.4; p<0.001). In a large sample population, the present study found that smoking, smoking cessation and serum α-klotho levels were associated in opposite directions.


Asunto(s)
Cese del Hábito de Fumar , Adulto , Masculino , Humanos , Estados Unidos/epidemiología , Persona de Mediana Edad , Anciano , Femenino , Encuestas Nutricionales , Estudios Transversales , Glucuronidasa , Fumar
2.
Cell J ; 24(3): 140-147, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35451584

RESUMEN

Objective: Dysregulation of long non-coding RNAs (lncRNAs) is associated with the progression of non-small cell lung cancer (NSCLC). This study aimed to investigate the role of long intergenic non-protein coding RNA 174 (LINC00174) in NSCLC. Materials and Methods: In this experimental study, LINC00174 expression in NSCLC tissues and cell lines was investigated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Besides, cell counting kit-8 (CCK-8), 5-bromo-2'-deoxyuridine (BrdU). Transwell and Flow Cytometry assays were applied to detect the regulatory function of LINC00174 on the growth, migration and apoptosis of NSCLC cells. Bioinformatics analysis, dual luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay predicted and verified the targeting relationship between LINC00174 and miR-31-5p, and between miR-31-5p and the 3´-untranslated region (3´UTR) of large tumor suppressor kinase 2 (LATS2), respectively. Western blotting was performed to detect the regulatory function of LINC00174 and miR-31-5p on LATS2 protein expression. Results: Compared with that in normal lung tissues, LINC00174 expression in NSCLC tissues and cell lines was reduced. LINC00174 expression was negatively associated with the TNM stage of the patients. Functional experiments showed that LINC00174 overexpression inhibited NSCLC cell multiplication and migration, and induced apoptosis. Furthermore, LINC00174 targeted miR-31-5p and repressed its expression. Additionally, LINC00174 upregulated LATS2 expression through competitively binding to miR-31-5p. Conclusion: LINC00174, as a competitive endogenous RNA, elevates LATS2 expression by adsorbing miR-31-5p, thereby inhibiting the viability and migration of NSCLC cells, and promoting apoptosis.

3.
J Infect Public Health ; 14(5): 620-627, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33848891

RESUMEN

INTRODUCTION: Many individuals test positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA after recovering from the coronavirus disease (COVID-19), but the incidence of reactivation is unknown. We, therefore, estimated the incidence of reactivation among individuals who had recovered from COVID-19 and determined its predictors. METHODS: In this retrospective cohort study, patients with COVID-19 were followed up for at least 14 days after two consecutive negative SARS-CoV-2 polymerase chain reaction test results obtained ≥24 h apart, and the frequency of SARS-CoV-2 reactivation was assessed. RESULTS: Of the 109 patients, 29 (27%) experienced reactivation, and seven (24%) of these were symptomatic. The mean period for the real-time PCR tests for SARS-CoV-2 from negative to positive results was 17 days. Compared with patients without reactivation, those with reactivation were significantly younger and more likely to have a lymphocyte count of <1500/µL (odds ratio [OR]: 0.34, 95% confidence interval [CI]: 0.12-0.94) and two or fewer symptoms (OR: 0.20, 95% CI: 0.07-0.55) during the initial episode. CONCLUSION: Risk-stratified surveillance should be conducted among patients who have recovered from COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos
4.
J Med Virol ; 93(5): 3033-3046, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33538342

RESUMEN

We primarily quantified exposure patterns, transmission characteristics, and the clinical spectrum of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among household contacts of individuals with severe coronavirus disease-2019 (COVID-19). We conducted a retrospective cohort study of 20 index patients hospitalized with severe COVID-19 and 79 of their household contacts. We determined the transmission frequency, range of manifestations of SARS-CoV-2 infection, and factors associated with infection in household settings. Of the 79 household contacts, 53 (67%) developed SARS-CoV-2 infection (49 [62%] symptomatic, 4 [5%] asymptomatic). Eight patients (10%) developed severe COVID-19, and one died of COVID-19 pneumonia (case-fatality rate: 1.9%). The probability of SARS-CoV-2 infection was similar in children and adults (55% vs. 72%, p = .14), with children being less likely to develop the symptomatic disease (46% vs. 68%, p = .06). Handwashing ≥ 5 times/day was associated with reduced infection risk (52.8% vs. 76.9%, p = .04). SARS-CoV-2 has a high frequency of transmission among household contacts. Nonhospitalized individuals with SARS-CoV-2 infection should be quarantined in patient care facilities rather than at home to minimize spread, if possible, and frequent handwashing should be practiced to prevent transmission.


Asunto(s)
COVID-19/epidemiología , COVID-19/transmisión , Trazado de Contacto/estadística & datos numéricos , SARS-CoV-2/patogenicidad , Adolescente , Adulto , Infecciones Asintomáticas/epidemiología , COVID-19/diagnóstico , COVID-19/prevención & control , Niño , Preescolar , Estudios de Cohortes , Composición Familiar , Femenino , Desinfección de las Manos , Humanos , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Cuarentena , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2/aislamiento & purificación , Adulto Joven
5.
J Genet ; 992020.
Artículo en Inglés | MEDLINE | ID: mdl-32661207

RESUMEN

Droughtmaster is a tropical breed of beef cattle that can survive in hot climates and easily adapt to torrid environments. These traits are important in livestock breeding. In this study, we genotyped five single-nucleotide polymorphisms (SNPs) of the AHSA2 gene from 190 cattle belonging to three different breeds (Droughtmaster, Angus and Simmental) by using snapshot technology. This work aimed to identify the valuable molecular marker of heat resistance in cattle. Results showed that Droughtmaster exhibited higher expected heterozygosity and polymorphic information content compared with the two other breeds. The AHSA2-1 locus deviated from the Hardy-Weinberg equilibrium in the Droughtmaster breed (P < 0.05). Two SNPs in Droughtmaster diverged significantly from Angus and Simmental. The SNPs were identified as AHSA2-3 and AHSA2-4, which were closely linked to the three breeds based on pair-wise FST. AHSA2-4 involved a missense mutation. In summary, the GG genotypes in AHSA2-3 and AHSA2-4 may be candidate genotypes associated with heat resistance traits and may serve as valuable genetic markers for breeding of heat-tolerant beef cattle in the future.


Asunto(s)
Marcadores Genéticos , Técnicas de Genotipaje/métodos , Chaperonas Moleculares/genética , Polimorfismo de Nucleótido Simple , Selección Genética , Animales , Cruzamiento , Bovinos , Genotipo , Fenotipo , Carácter Cuantitativo Heredable
6.
Open Forum Infect Dis ; 7(5): ofaa169, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32490031

RESUMEN

BACKGROUND: There is currently a lack of nonspecific laboratory indicators as a quantitative standard to distinguish between the 2019 coronavirus disease (COVID-19) and an influenza A or B virus infection. Thus, the aim of this study was to establish a nomogram to detect COVID-19. METHODS: A nomogram was established using data collected from 457 patients (181 with COVID-19 and 276 with influenza A or B infection) in China. The nomogram used age, lymphocyte percentage, and monocyte count to differentiate COVID-19 from influenza. RESULTS: Our nomogram predicted probabilities of COVID-19 with an area under the receiver operating characteristic curve of 0.913 (95% confidence interval [CI], 0.883-0.937), greater than that of the lymphocyte:monocyte ratio (0.849; 95% CI, 0.812-0.880; P = .0007), lymphocyte percentage (0.808; 95% CI, 0.768-0.843; P < .0001), monocyte count (0.780; 95% CI, 0.739-0.817; P < .0001), or age (0.656; 95% CI, 0.610-0.699; P < .0001). The predicted probability conformed to the real observation outcomes of COVID-19, according to the calibration curves. CONCLUSIONS: We found that age, lymphocyte percentage, and monocyte count are risk factors for the early-stage prediction of patients infected with the 2019 novel coronavirus. As such, our research provides a useful test for doctors to differentiate COVID-19 from influenza.

7.
J Inflamm (Lond) ; 17: 19, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32431566

RESUMEN

BACKGROUND: To investigate the efficacy and safety of aerosol inhalation of recombinant human interferon α1b (IFNα1b) injection for noninfluenza viral pneumonia. METHODS: One hundred sixty-four patients with noninfluenza viral pneumonia were divided into IFNα1b and control groups. The IFNα1b group received routine treatment + aerosol inhalation of recombinant human IFNα1b injection (50 µg × 2 injections, bid). The control group received routine treatment + IFN analog (two injections, bid). Overall response rate (ORR) of five kinds clinical symptoms. Further outcomes were daily average score and the response rate of each of the symptoms above. RESULTS: A total of 163 patients were included in the full analysis set (FAS) and 151 patients were included in the per-protocol set (PPS). After 7 days of treatment, ORR of clinical symptoms was higher in IFNα1b group than that in control group for both the FAS and PPS. Moreover, after 7 days of treatment, the daily score of three efficacy indexes including expectoration, respiratory rate, and pulmonary rales were improved. The ORRs for expectoration and pulmonary rales were higher in the IFNα1b group than in the control group (P < 0.05). There were no significant differences of the ORRs for coughing, chest pain and respiratory rate between the two groups (P > 0.05). The incidence of adverse events was 6.5% (n = 5) in IFNα1b group and 3.5% (n = 3) in control group (P > 0.05). CONCLUSION: Aerosol inhalation of recombinant human IFNα1b is safe and it can improve the clinical symptoms of noninfluenza viral pneumonia.

8.
J Transl Med ; 18(1): 206, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32434518

RESUMEN

BACKGROUND: Patients with critical illness due to infection with the 2019 coronavirus disease (COVID-19) show rapid disease progression to acute respiratory failure. The study aimed to screen the most useful predictive factor for critical illness caused by COVID-19. METHODS: The study prospectively involved 61 patients with COVID-19 infection as a derivation cohort, and 54 patients as a validation cohort. The predictive factor for critical illness was selected using LASSO regression analysis. A nomogram based on non-specific laboratory indicators was built to predict the probability of critical illness. RESULTS: The neutrophil-to-lymphocyte ratio (NLR) was identified as an independent risk factor for critical illness in patients with COVID-19 infection. The NLR had an area under receiver operating characteristic of 0.849 (95% confidence interval [CI], 0.707 to 0.991) in the derivation cohort and 0.867 (95% CI 0.747 to 0.944) in the validation cohort, the calibration curves fitted well, and the decision and clinical impact curves showed that the NLR had high standardized net benefit. In addition, the incidence of critical illness was 9.1% (1/11) for patients aged ≥ 50 and having an NLR < 3.13, and 50% (7/14) patients with age ≥ 50 and NLR ≥ 3.13 were predicted to develop critical illness. Based on the risk stratification of NLR according to age, this study has developed a COVID-19 pneumonia management process. CONCLUSIONS: We found that NLR is a predictive factor for early-stage prediction of patients infected with COVID-19 who are likely to develop critical illness. Patients aged ≥ 50 and having an NLR ≥ 3.13 are predicted to develop critical illness, and they should thus have rapid access to an intensive care unit if necessary.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Enfermedad Crítica , Linfocitos/patología , Neutrófilos/patología , Neumonía Viral/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Betacoronavirus/patogenicidad , COVID-19 , Niño , Preescolar , Estudios de Cohortes , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/patología , Progresión de la Enfermedad , Femenino , Historia del Siglo XXI , Humanos , Lactante , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/patología , Pronóstico , Estudios Prospectivos , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Adulto Joven
9.
J Infect ; 81(2): e26-e30, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32335171

RESUMEN

BACKGROUND: Since its discovery, SARS-CoV-2 has been spread throughout China before becoming a global pandemic. In Beijing, family clusters are the main mode of human-human transmission accounting for 57.6% of the total confirmed cases. METHOD: We present the epidemiological and clinical features of the clusters of three large and one small families. RESULT: Our results revealed that SARS-CoV-2 is transmitted quickly through contact with index case, and a total of 22/24 infections were observed. Among those infected, 20/22 had mild symptoms and only two had moderate to severe clinical manifestations. Children in the families generally showed milder symptoms. The incubation period varied from 2 to 13 days, and the shedding of virus from the upper respiratory tract lasted from 5 to over 30 days. A prolonged period of virus shedding (>30 days) in upper respiratory tract was observed in 6/24 cases. CONCLUSION: SARS-CoV-2 is transmitted quickly in the form of family clusters. While the infection rate is high within the cluster, the disease manifestations, latent period, and virus shedding period varied greatly. We therefore recommend rigorously testing contacts even during the no-symptom phase and consider whether viral shedding has ceased before stopping isolation measures for an individual.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Familia , Pandemias/estadística & datos numéricos , Neumonía Viral/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Beijing/epidemiología , Betacoronavirus , COVID-19 , Niño , Preescolar , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/transmisión , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Neumonía Viral/patología , Neumonía Viral/transmisión , SARS-CoV-2
10.
BMC Genet ; 21(1): 32, 2020 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-32171250

RESUMEN

BACKGROUND: Body size traits as one of the main breeding selection criteria was widely used to monitor cattle growth and to evaluate the selection response. In this study, body size was defined as body height (BH), body length (BL), hip height (HH), heart size (HS), abdominal size (AS), and cannon bone size (CS). We performed genome-wide association studies (GWAS) of these traits over the course of three growth stages (6, 12 and 18 months after birth) using three statistical models, single-trait GWAS, multi-trait GWAS and LONG-GWAS. The Illumina Bovine HD 770 K BeadChip was used to identify genomic single nucleotide polymorphisms (SNPs) in 1217 individuals. RESULTS: In total, 19, 29, and 10 significant SNPs were identified by the three models, respectively. Among these, 21 genes were promising candidate genes, including SOX2, SNRPD1, RASGEF1B, EFNA5, PTBP1, SNX9, SV2C, PKDCC, SYNDIG1, AKR1E2, and PRIM2 identified by single-trait analysis; SLC37A1, LAP3, PCDH7, MANEA, and LHCGR identified by multi-trait analysis; and P2RY1, MPZL1, LINGO2, CMIP, and WSCD1 identified by LONG-GWAS. CONCLUSIONS: Multiple association analysis was performed for six growth traits at each growth stage. These findings offer valuable insights for the further investigation of potential genetic mechanism of growth traits in Simmental beef cattle.


Asunto(s)
Tamaño Corporal/genética , Bovinos/genética , Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo/genética , Animales , Cruzamiento , Bovinos/crecimiento & desarrollo , Genómica , Haplotipos/genética
11.
Genes Cancer ; 7(3-4): 125-35, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27382436

RESUMEN

Hepatoblastoma is the most common liver cancer in children, accounting for over 65% of all childhood liver malignancies. Hepatoblastoma is distinct from adult liver cancer in that it is not associated with hepatitis virus infection, cirrhosis, or other underlying liver pathology. The paucity of appropriate cell and animal models has been hampering the mechanistic understanding of hepatoblastoma pathogenesis. Consequently, there is no molecularly targeted therapy for hepatoblastoma. To gain insight into cytokine signaling in hepatoblastoma, we employed mass spectrometry to analyze the proteins secreted from Hep293TT hepatoblastoma cell line we established and identified the specific secretion of fibroblast growth factor 19 (FGF19), a growth factor for liver cells. We determined that silencing FGF19 by shRNAs or neutralizing secreted FGF19 by anti-FGF19 antibody inhibits the proliferation of hepatoblastoma cells. Furthermore, blocking FGF19 signaling by an FGF receptor kinase inhibitor suppressed hepatoblastoma growth. RNA expression analysis in hepatoblastoma tumors revealed that the high expression of FGF19 signaling pathway components as well as the low expression of FGF19 signaling repression targets correlates with the aggressiveness of the tumors. These results suggest the role of FGF19 as autocrine growth factor for hepatoblastoma.

12.
Exp Gerontol ; 73: 1-4, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26547052

RESUMEN

Cellular senescence has been proposed to play critical roles in tumor suppression and organismal aging, but the molecular mechanism of senescence remains incompletely understood. Here we report that a putative lysosomal carbohydrate efflux transporter, Spinster, induces cellular senescence in human primary fibroblasts. Administration of d-galactose synergistically enhanced Spinster-induced senescence and this synergism required the transporter activity of Spinster. Intracellular d-galactose is metabolized to galactose-1-phosphate by galactokinase. Galactokinase-deficient fibroblasts, which accumulate intracellular d-galactose, displayed increased baseline senescence. Senescence of galactokinase-deficient fibroblasts was further enhanced by d-galactose administration and was diminished by restoration of wild-type galactokinase expression. Silencing galactokinase in normal fibroblasts also induced senescence. These results suggest a role for intracellular galactose in the induction of cellular senescence.


Asunto(s)
Senescencia Celular/fisiología , Galactosa/fisiología , Proteínas Adaptadoras Transductoras de Señales/farmacología , Proteínas Adaptadoras Transductoras de Señales/fisiología , Células Cultivadas , Senescencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Galactoquinasa/deficiencia , Galactoquinasa/fisiología , Galactosa/farmacología , Humanos , Lisosomas/metabolismo , Proteínas de la Membrana/farmacología , Proteínas de la Membrana/fisiología
13.
Genes Cancer ; 6(11-12): 452-61, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26807198

RESUMEN

Ewing sarcoma is a cancer of bone and soft tissue in children that is characterized by a chromosomal translocation involving EWS and an Ets family transcription factor, most commonly FLI-1. The EWS-FLI-1 fusion oncogene is widely believed to play a central role in Ewing sarcoma. The EWS-FLI-1 gene product regulates the expression of a number of genes important for cancer progression, can transform mouse cells such as NIH3T3 and C3H10T1/2, and is necessary for proliferation and tumorigenicity of Ewing sarcoma cells, suggesting that EWS-FLI-1 is the causative oncogene. However, a variety of evidence also suggest that EWS-FLI-1 alone cannot fully explain the Ewing sarcomagenesis. Here we report that FLI-1-EWS, a fusion gene reciprocal to EWS-FLI-1, is frequently expressed in Ewing sarcoma. We present evidence suggesting that endogenous FLI-1-EWS is required for Ewing sarcoma growth and that FLI-1-EWS cooperates with EWS-FLI-1 in human mesenchymal stem cells, putative cells of origin of Ewing sarcoma, through abrogation of the proliferation arrest induced by EWS- FLI-1.

14.
J Proteome Res ; 13(8): 3783-91, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24999758

RESUMEN

Ewing sarcoma is a cancer of bone and soft tissue in children that is characterized by a chromosomal translocation involving EWS and an Ets family transcription factor, most commonly Fli-1. EWS-Fli-1 fusion accounts for 85% of cases. The growth and survival of Ewing sarcoma cells are critically dependent on EWS-Fli-1. A large body of evidence has established that EWS-Fli-1 functions as a DNA-binding transcription factor that regulates the expression of a number of genes important for cell proliferation and transformation. However, little is known about the biochemical properties of the EWS-Fli-1 protein. We undertook a series of proteomic analyses to dissect the EWS-Fli-1 interactome. Employing a proximity-dependent biotinylation technique, BioID, we identified cation-independent mannose 6-phosphate receptor (CIMPR) as a protein located in the vicinity of EWS-Fli-1 within a cell. CIMPR is a cargo that mediates the delivery of lysosomal hydrolases from the trans-Golgi network to the endosome, which are subsequently transferred to the lysosomes. Further molecular cell biological analyses uncovered a role for lysosomes in the turnover of the EWS-Fli-1 protein. We demonstrate that an mTORC1 active-site inhibitor, torin 1, which stimulates the TFEB-lysosome pathway, can induce the degradation of EWS-Fli-1, suggesting a potential therapeutic approach to target EWS-Fli-1 for degradation.


Asunto(s)
Lisosomas/metabolismo , Proteínas de Fusión Oncogénica/fisiología , Proteómica , Proteína Proto-Oncogénica c-fli-1/fisiología , Proteína EWS de Unión a ARN/fisiología , Sarcoma de Ewing/tratamiento farmacológico , Biotinilación , Dominio Catalítico , Línea Celular Tumoral , Proliferación Celular , Transformación Celular Neoplásica/genética , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Células HeLa , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Complejos Multiproteicos/metabolismo , Proteoma/metabolismo , Sarcoma de Ewing/patología , Serina-Treonina Quinasas TOR/metabolismo , Espectrometría de Masas en Tándem , Factores de Transcripción/metabolismo , Red trans-Golgi/metabolismo
15.
Mol Cell Biol ; 32(21): 4388-99, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22927647

RESUMEN

Cellular senescence has emerged as a critical tumor suppressive mechanism in recent years, but relatively little is known about how senescence occurs. Here, we report that secreted Frizzled-related protein 1 (SFRP1), a secreted antagonist of Wnt signaling, is oversecreted upon cellular senescence caused by DNA damage or oxidative stress. SFRP1 is necessary for stress-induced senescence caused by these factors and is sufficient for the induction of senescence phenotypes. We present evidence suggesting that SFRP1 functions as a secreted mediator of senescence through inhibition of Wnt signaling and activation of the retinoblastoma (Rb) pathway and that cancer-associated SFRP1 mutants are defective for senescence induction.


Asunto(s)
Senescencia Celular , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas de la Membrana/metabolismo , Proteína de Retinoblastoma/metabolismo , Proteínas Wnt/antagonistas & inhibidores , Vía de Señalización Wnt , Línea Celular Tumoral , Proliferación Celular , Daño del ADN , Fibroblastos , Regulación Neoplásica de la Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Proteínas de la Membrana/genética , Mutación , Estrés Oxidativo , Regiones Promotoras Genéticas , Interferencia de ARN , ARN Interferente Pequeño , Transducción de Señal , Proteínas Wnt/genética
16.
Proc Natl Acad Sci U S A ; 109(30): 12052-7, 2012 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-22778398

RESUMEN

Cellular senescence is widely believed to play a key role in tumor suppression, but the molecular pathways that regulate senescence are only incompletely understood. By using a secretome proteomics approach, we identified insulin-like growth factor binding protein 3 (IGFBP3) as a secreted mediator of breast cancer senescence upon chemotherapeutic drug treatment. The senescence-inducing activity of IGFBP3 is inhibited by tissue-type plasminogen activator-mediated proteolysis, which is counteracted by plasminogen activator inhibitor 1 (PAI-1), another secreted mediator of senescence. We demonstrate that IGFBP3 is a critical downstream target of PAI-1-induced senescence. These results suggest a role for an extracellular cascade of secreted proteins in the regulation of cellular senescence.


Asunto(s)
Senescencia Celular/fisiología , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Neoplasias/tratamiento farmacológico , Inhibidor 1 de Activador Plasminogénico/metabolismo , Proteolisis/efectos de los fármacos , Estrés Fisiológico/fisiología , Activador de Tejido Plasminógeno/farmacología , Análisis de Varianza , Línea Celular Tumoral , Medios de Cultivo/química , Cartilla de ADN/genética , Doxorrubicina/farmacología , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Humanos , Immunoblotting , Inmunohistoquímica , Neoplasias/metabolismo , Neoplasias/fisiopatología , Proteómica/métodos , ARN Interferente Pequeño/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Activador de Tejido Plasminógeno/metabolismo , Células Tumorales Cultivadas , beta-Galactosidasa
17.
Arch Biochem Biophys ; 518(2): 103-10, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22234250

RESUMEN

Inactivation of the von Hippel-Lindau (VHL) tumor suppressor is associated with renal carcinoma, hemangioblastoma and pheochromocytoma. The VHL protein is a component of a ubiquitin ligase complex that ubiquitinates and degrades hypoxia inducible factor-α (HIF-α). Degradation of HIF-α by VHL is proposed to suppress tumorigenesis and tumor angiogenesis. Several lines of evidence also suggest important roles for HIF-independent VHL functions in tumor suppression and other biological processes. Using GST-VHL pull-down experiment and mass spectrometry, we detected an interaction between VHL and heterochromatin protein 1 (HP1). We identified a conserved HP1-binding motif (PXVXL) in the ß domain of VHL, which is disrupted in a renal carcinoma-associated P81S mutant. We show that the VHL P81S mutant displays reduced binding to HP1, yet retains the ability to interact with elongin B, elongin C, and cullin 2 and is fully capable of degrading HIF-α. We also demonstrate that HP1 increases the chromatin association of VHL. These results suggest a role for the VHL-HP1 interaction in VHL chromatin targeting.


Asunto(s)
Cromatina/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Renales/metabolismo , Proteolisis , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Secuencias de Aminoácidos , Sustitución de Aminoácidos , Animales , Línea Celular , Cromatina/genética , Homólogo de la Proteína Chromobox 5 , Proteínas Cromosómicas no Histona/genética , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Elonguina , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Neoplasias Renales/genética , Ratones , Mutación Missense , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ubiquitinación/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética
18.
J Proteome Res ; 10(11): 5175-82, 2011 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-21942715

RESUMEN

The von Hippel-Lindau (VHL) tumor suppressor gene encodes a component of a ubiquitin ligase complex containing elongin B, elongin C, cullin 2, and Rbx1, which acts as a negative regulator of hypoxia inducible factor (HIF). VHL ubiquitinates and degrades the alpha subunits of HIF, and this is proposed to suppress tumorigenesis and tumor angiogenesis. Several lines of evidence also suggest important roles for HIF-independent VHL functions in the maintenance of primary cilium, extracellular matrix formation, and tumor suppression. We undertook a series of proteomic analyses to gain a comprehensive picture of the VHL-interacting proteins. We found that the ARF tumor suppressor interacts with VHL30, a longer VHL isoform, but not with VHL19, a shorter VHL isoform. ARF was found to release VHL30 from the E3 ligase complex, promoting the binding of VHL30 to a protein arginine methyltransferase, PRMT3. Our analysis of the VHL19 interactome also uncovered that VHL19 displays an affinity to collagens and their biosynthesis enzymes.


Asunto(s)
Mapeo de Interacción de Proteínas , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína p14ARF Supresora de Tumor/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Arginina/metabolismo , Línea Celular Tumoral , Colágeno/biosíntesis , Colágeno/metabolismo , Proteínas Cullin/metabolismo , Elonguina , Células HEK293 , Humanos , Metilación , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/metabolismo , Unión Proteica , Isoformas de Proteínas/metabolismo , Proteómica , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Complejos de Ubiquitina-Proteína Ligasa/metabolismo
19.
J Proteome Res ; 10(11): 5191-8, 2011 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-21950761

RESUMEN

Mutation of the BRCA1 tumor suppressor gene predisposes women to hereditary breast and ovarian cancers. BRCA1 forms a heterodimer with BARD1. The BRCA1/BARD1 heterodimer has ubiquitin ligase activity, considered to play crucial roles in tumor suppression and DNA damage response. Nevertheless, relevant BRCA1 substrates are poorly defined. We have developed a new approach to systematically identify the substrates of ubiquitin ligases by identifying proteins that display an enhanced incorporation of His-tagged ubiquitin upon ligase coexpression; using this method, we identified several candidate substrates for BRCA1. These include scaffold attachment factor B2 (SAFB2) and Tel2 as well as BARD1. BRCA1 was found to enhance SAFB protein expression and induce Tel2 nuclear translocation. Identification of the ubiquitination substrates has been a major obstacle to understanding the functions of ubiquitin ligases. The quantitative proteomics approach we devised for the identification of BRCA1 substrates will facilitate the identification of ubiquitin ligase-substrate pairs.


Asunto(s)
Proteína BRCA1/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Animales , Proteína BRCA1/genética , Núcleo Celular/metabolismo , Células Cultivadas , Expresión Génica , Regulación de la Expresión Génica , Humanos , Proteínas de Unión a la Región de Fijación a la Matriz/genética , Proteínas de Unión a la Región de Fijación a la Matriz/metabolismo , Ratones , Complejos Multiproteicos/metabolismo , Proteínas Asociadas a Matriz Nuclear/genética , Proteínas Asociadas a Matriz Nuclear/metabolismo , Transporte de Proteínas , Proteómica , Proteínas Proto-Oncogénicas c-ets/metabolismo , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Proteínas Supresoras de Tumor/genética , Ubiquitina-Proteína Ligasas/genética , Proteínas Ubiquitinadas/genética , Proteínas Ubiquitinadas/aislamiento & purificación , Proteínas Ubiquitinadas/metabolismo
20.
PLoS One ; 6(2): e16975, 2011 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21386990

RESUMEN

BACKGROUND: The von Hippel-Lindau (VHL) tumor suppressor gene encodes a component of a ubiquitin ligase complex, which is best understood as a negative regulator of hypoxia inducible factor (HIF). VHL ubiquitinates and degrades the α subunits of HIF, and this is proposed to suppress tumorigenesis and tumor angiogenesis. However, several lines of evidence suggest that there are unidentified substrates or targets for VHL that play important roles in tumor suppression. METHODOLOGY/PRINCIPAL FINDINGS: Employing quantitative proteomics, we developed an approach to systematically identify the substrates of ubiquitin ligases and using this method, we identified the Myb-binding protein p160 as a novel substrate of VHL. CONCLUSIONS/SIGNIFICANCE: A major barrier to understanding the functions of ubiquitin ligases has been the difficulty in pinpointing their ubiquitination substrates. The quantitative proteomics approach we devised for the identification of VHL substrates will be widely applicable to other ubiquitin ligases.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas Nucleares/metabolismo , Proteómica , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/fisiología , Animales , Células 3T3 BALB , Células Cultivadas , Proteínas de Unión al ADN , Deferoxamina/farmacología , Inhibidores Enzimáticos/farmacología , Humanos , Marcaje Isotópico/métodos , Leupeptinas/farmacología , Ratones , Modelos Biológicos , Complejo de la Endopetidasa Proteasomal/metabolismo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteómica/métodos , Proteínas de Unión al ARN , Sideróforos/farmacología , Factores de Transcripción , Ubiquitina-Proteína Ligasas/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo
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