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1.
Med Humanit ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38604655

RESUMEN

This article explores the feminist social critique in the 'big heroine' drama, a newly emerged genre of television that focuses on empowering yet dramatic stories of urban women in contemporary China. The article theorises the genre as a site of ongoing contestations to inform and critique women's maternal reality in neoliberal, pronatalist China. The big heroine genre is situated in the postsocialist structure of feeling defined by alienation and precarity, responding to China's need to stabilise the emerging population crisis and labour shortage. Using a popular instance within the genre, Left Right (2022), as a case study, the article argues that the show validates the legitimacy of women's anxieties and challenges in maternity and then invites viewers to engage in a multifaceted analysis of the intricate web of structural injustices women experience in pregnancy, childbirth, the postpartum and having a second child. By doing so, it not only resonates with viewers' yearning for recognition and empathy but also stimulates a broader discourse on new and persisting maternal challenges in pronatalist China. I conclude that the genre's contradictory and contingent nature mirrors the complexities of the Chinese party-state's attempt to navigate the ideological instability surrounding maternity and motherhood. The genre is progressive in its alternative imagination of kinship and care networks for women navigating the moral, medical, and cultural dilemmas of the maternal body and motherhood in the moment of the state's transitioning into a more aggressive form of pronatalism.

2.
Hepatology ; 75(3): 600-609, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34528267

RESUMEN

BACKGROUND AND AIMS: The Liver Frailty Index (LFI) is a well-studied tool that evaluates frailty in patients with cirrhosis. Consisting of grip strength, chair stands, and balance testing, the LFI has been associated with increased mortality in patients awaiting liver transplant. We aimed to extend our understanding of frailty in cirrhosis by exploring the relationship between the LFI and the risk of (1) cirrhosis progression, (2) mortality, and (3) unplanned hospitalizations, in both compensated and decompensated disease. APPROACH AND RESULTS: Adult patients with cirrhosis from four centers in North America and one in India were included. Frailty was measured at baseline using the LFI and categorized as robust (LFI < 3.2), prefrail (LFI 3.2-4.5), and frail (LFI > 4.5). Progression of cirrhosis was defined by an increase in clinical stage, ranging from 1 to 5, from baseline using the D'Amico classification. Factors associated with progression, mortality, and hospitalizations were evaluated using multivariate regression models, with transplant as a competing risk. In total, 822 patients with cirrhosis were included. Average Model for End-Stage Liver Disease (MELD) score was 15.5 ± 6.0. In patients with compensated cirrhosis, being frail versus robust was associated with increased risk of progression to the next cirrhosis stage or to death (HR, 2.45; 95% CI, 1.14-5.29) and with an increased risk of unplanned hospitalizations (2.32; 95% CI, 1.13-4.79), after adjusting for age, sex, and MELD score. Similar HRs were observed in patients with decompensated cirrhosis. CONCLUSIONS: Frailty was an independent predictor of cirrhosis progression or death and unplanned hospitalization across patients with compensated and decompensated cirrhosis. Future studies are needed to evaluate the possibility of slowing cirrhosis disease progression by reversing or preventing frailty.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Fragilidad/diagnóstico , Cirrosis Hepática , Progresión de la Enfermedad , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/mortalidad , Enfermedad Hepática en Estado Terminal/fisiopatología , Femenino , Fragilidad/complicaciones , Fragilidad/fisiopatología , Fragilidad/prevención & control , Fuerza de la Mano , Hospitalización/estadística & datos numéricos , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/fisiopatología , Masculino , Persona de Mediana Edad , Mortalidad , Puntuaciones en la Disfunción de Órganos , Evaluación de Resultado en la Atención de Salud , Equilibrio Postural , Valor Predictivo de las Pruebas , Medición de Riesgo/métodos
3.
J Am Soc Nephrol ; 33(5): 1011-1032, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35232774

RESUMEN

BACKGROUND: Vascular calcification is associated with cardiovascular morbidity and mortality in people with CKD. Evidence-based interventions that may attenuate its progression in CKD remain uncertain. METHODS: We conducted a systematic review of prospective clinical trials of interventions to attenuate vascular calcification in people with CKD, compared with placebo, another comparator, or standard of care. We included prospective clinical trials (randomized and nonrandomized) involving participants with stage 3-5D CKD or kidney transplant recipients; the outcome was vascular calcification measured using radiologic methods. Quality of evidence was determined by the Cochrane risk of bias assessment tool and the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) method. RESULTS: There were 77 trials (63 randomized) involving 6898 participants eligible for inclusion (median sample size, 50; median duration, 12 months); 58 involved participants on dialysis, 15 involved individuals with nondialysis CKD, and 4 involved kidney transplant recipients. Risk of bias was moderate over all. Trials involving magnesium and sodium thiosulfate consistently showed attenuation of vascular calcification. Trials involving intestinal phosphate binders, alterations in dialysate calcium concentration, vitamin K therapy, calcimimetics, and antiresorptive agents had conflicting or inconclusive outcomes. Trials involving vitamin D therapy and HMG-CoA reductase inhibitors did not demonstrate attenuation of vascular calcification. Mixed results were reported for single studies of exercise, vitamin E-coated or high-flux hemodialysis membranes, interdialytic sodium bicarbonate, SNF472, spironolactone, sotatercept, nicotinamide, and oral activated charcoal. CONCLUSIONS: Currently, there are insufficient or conflicting data regarding interventions evaluated in clinical trials for mitigation of vascular calcification in people with CKD. Therapy involving magnesium or sodium thiosulfate appears most promising, but evaluable studies were small and of short duration.


Asunto(s)
Insuficiencia Renal Crónica , Calcificación Vascular , Femenino , Humanos , Magnesio , Masculino , Estudios Prospectivos , Diálisis Renal , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/terapia , Calcificación Vascular/etiología
4.
J Viral Hepat ; 28(4): 582-591, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33372359

RESUMEN

There has been an increase in hepatitis B (HBV) detection during pregnancy in the United States and an emphasis on measures to decrease mother-to-child transmission of HBV. We performed a multicentre retrospective study (2015-2018) evaluating care among all women with HBV during pregnancy. We determined rates and predictors of adherence to key maternal care measures including: (1) referral to HBV specialty care, (2) assessment of HBV DNA, and (3) initiation of antiviral therapy, and (4) rates of HBIG and HBV vaccine completion in infants. We evaluated two interventions to improve HBV care: (1) clinical decision support with best practice alert and (2) co-location of HBV care in obstetrics department. We identified 372 women with HBV during pregnancy. Patients had a median age of 33 (IQR 29, 36), were mostly of Asian (49%) or Black (36%) race, HBeAg-negative (83%) with HBV DNA ≤2000 IU/mL (65%) and maximum ALT ≤25 (66%). Regarding care measures, 62% were referred to an HBV specialist, 85% had HBV DNA checked during pregnancy and 68% with HBV DNA ≥200,000 were initiated on antiviral therapy. Co-located obstetric-liver diseases clinics appeared to improve adherence to maternal care measures. All infants received HBIG and the first HBV vaccine dose, 106 (81%) received the second, 94 (74%) received the 3rd dose, but fewer at the recommended time intervals. We identified clear gaps in adherence to HBV care measures for both mothers and infants. Co-location of HBV care in the obstetrics department shows promise in improving adherence to maternal care measures.


Asunto(s)
Hepatitis B , Complicaciones Infecciosas del Embarazo , ADN Viral , Femenino , Hepatitis B/tratamiento farmacológico , Hepatitis B/epidemiología , Hepatitis B/prevención & control , Antígenos de Superficie de la Hepatitis B , Vacunas contra Hepatitis B , Antígenos e de la Hepatitis B , Virus de la Hepatitis B , Hospitales , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Estudios Retrospectivos , Estados Unidos
5.
Liver Int ; 41(10): 2467-2473, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34219362

RESUMEN

BACKGROUND & AIMS: Cirrhosis leads to malnutrition and muscle wasting that manifests as frailty, which may be influenced by cirrhosis aetiology. We aimed to characterize the relationship between frailty and cirrhosis aetiology. METHODS: Included were adults with cirrhosis listed for liver transplantation (LT) at 10 US centrer who underwent ambulatory testing with the Liver Frailty Index (LFI; 'frail' = LFI ≥ 4.4). We used logistic regression to associate aetiologies and frailty, and competing risk regression (LT as the competing risk) to determine associations with waitlist mortality (death/delisting for sickness). RESULTS: Of 1,623 patients, rates of frailty differed by aetiology: 22% in chronic hepatitis C, 31% in alcohol-associated liver disease (ALD), 32% in non-alcoholic fatty liver disease (NAFLD), 21% in autoimmune/cholestatic and 31% in 'other' (P < .001). In univariable logistic regression, ALD (OR 1.53, 95% CI 1.12-2.09), NAFLD (OR 1.64, 95% CI 1.18-2.29) and 'other' (OR 1.58, 95% CI 1.06-2.36) were associated with frailty. In multivariable logistic regression, only ALD (OR 1.40; 95% 1.01-1.94) and 'other' (OR 1.59; 95% 1.05-2.40) remained associated with frailty. A total of 281 (17%) patients died/were delisted for sickness. In multivariable competing risk regression, LFI was associated with waitlist mortality (sHR 1.05, 95% CI 1.03-1.06), but aetiology was not (P > .05 for each). No interaction between frailty and aetiology on the association with waitlist mortality was found (P > .05 for each interaction term). CONCLUSIONS: Frailty is more common in patients with ALD, NAFLD and 'other' aetiologies. However, frailty was associated with waitlist mortality independent of cirrhosis aetiology, supporting the applicability of frailty across all cirrhosis aetiologies.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Fragilidad , Trasplante de Hígado , Adulto , Fragilidad/diagnóstico , Humanos , Cirrosis Hepática , Listas de Espera
6.
Brain Behav Immun ; 72: 2-13, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29102801

RESUMEN

Stress is a major risk factor for psychiatric disorder including major depressive disorder (MDD) and can induce inflammation, which is known to be dysregulated in depression. Several clinical and pre-clinical studies have demonstrated a strong association between depressive symptoms and the expression of factors that increase inflammation. Conversely, administration of anti-inflammatory agents has been shown to ameliorate depressive symptoms, demonstrating the importance of inflammation as a mediator of depression. Although it is clear that inflammation plays a role in the pathophysiology of depression, the mechanism by which inflammation is activated in mood disorders remains unclear. To address this issue, studies have investigated the role of pattern recognition receptor (PRR) activation in stress-induced inflammation and mood disorders. However, the identification of the endogenous factors, referred to as danger-associated molecular patterns (DAMP) that activate these receptors remains understudied. Here we review the role of DAMPs in depression and highlight the clinical evidence for elevation of DAMP signaling in MDD patients and in pre-clinical animal stress models of depression.


Asunto(s)
Alarminas/fisiología , Depresión/inmunología , Receptores de Reconocimiento de Patrones/fisiología , Alarminas/inmunología , Alarminas/metabolismo , Animales , Citocinas , Depresión/fisiopatología , Trastorno Depresivo Mayor/inmunología , Trastorno Depresivo Mayor/metabolismo , Humanos , Inflamasomas/metabolismo , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/fisiopatología , Trastornos del Humor/inmunología , Trastornos del Humor/fisiopatología , Receptores de Reconocimiento de Patrones/inmunología , Transducción de Señal , Estrés Psicológico/inmunología
7.
Alcohol Clin Exp Res ; 39(6): 969-79, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25903395

RESUMEN

BACKGROUND: The Wnt/ß-catenin pathway regulates liver growth, repair, and regeneration. Chronic ethanol (EtOH) exposure blunts normal liver regenerative responses, in part by inhibiting insulin/IGF signaling, and correspondingly, previous studies showed that EtOH-impaired liver regeneration could be restored by insulin sensitizer (proliferator-activated receptor [PPAR]-δ agonist) treatment. As Wnt/ß-catenin functions overlap and cross talk with insulin/IGF pathways, we investigated the effects of EtOH exposure and PPAR-δ agonist treatment on Wnt pathway gene expression in relation to liver regeneration. METHODS: Adult male Long Evans rats were fed with isocaloric liquid diets containing 0 or 37% EtOH for 8 weeks and also treated with vehicle or a PPAR-δ agonist during the last 3 weeks of the feeding regimen. The rats were then subjected to 70% partial hepatectomy (PH) and livers harvested at various post-PH time points were used to quantitate expression of 19 Wnt pathway genes using Quantigene 2.0 Multiplex Assay. RESULTS: EtOH broadly inhibited expression of Wnt/ß-catenin signaling-related genes, including down-regulation of Wnt1, Fzd3, Lef1, and Bcl9 throughout the post-PH time course (0 to 72 hours), and suppression of Wnt7a, Ccnd1, Fgf4, Wif1, Sfrp2, and Sfrp5 at 18- and 24-hour post-PH time points. PPAR-δ agonist treatments rescued the EtOH-induced suppression of Wnt1, Wnt7a, Fzd3, Lef1, Bcl9, Ccnd1, and Sfrp2 gene expression in liver, corresponding with the improvements in DNA synthesis and restoration of hepatic architecture. CONCLUSIONS: Chronic high-dose EtOH exposures inhibit Wnt signaling, which likely contributes to the impairments in liver regeneration. Therapeutic effects of PPAR-δ agonists extend beyond restoration of insulin/IGF signaling mechanisms and are mediated in part by enhancement of Wnt pathway signaling. Future studies will determine the degree to which targeted restoration of Wnt signaling is sufficient to improve liver regeneration and remodeling in the context of chronic EtOH exposure.


Asunto(s)
Etanol/farmacología , PPAR delta/agonistas , Fenoxiacetatos/farmacología , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo , Animales , Expresión Génica/efectos de los fármacos , Hepatectomía , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , Regeneración Hepática/efectos de los fármacos , Regeneración Hepática/genética , Masculino , Datos de Secuencia Molecular , Ratas , Ratas Long-Evans , Vía de Señalización Wnt/genética
8.
Liver Int ; 33(10): 1536-48, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23648141

RESUMEN

BACKGROUND: T-cell factor (TCF) proteins represent key transcription factors that activate Wnt/ß-catenin signalling. We have reported that a pair of TCF-4 isoforms (TCF-4C and TCF-4D) exhibit differential TCF transcriptional activity in hepatocellular carcinoma (HCC) cells, although their structure differs by only the presence (TCF-4D) or absence (TCF-4C) of exon 4. AIM: To demonstrate a regulatory role of exon 4 in HCC development. METHODS: TCF-4C and TCF-4D expression profiles were examined in 27 pairs of human HCC and adjacent liver tissues. The functional role of the TCF-4 isoforms was evaluated in OUMS-29 (an immortalized hepatocyte-derived) and HAK-1A (a well-differentiated HCC) cell lines using stable clones overexpressing the TCF-4 isoforms. RESULTS: TCF-4C was significantly upregulated in HCC tissues compared with corresponding peritumour and normal liver tissues; in contrast, there was no difference in TCF-4D expression. TCF-4C clones derived from both cell lines exhibited increased TCF activity, Wnt-responsive target genes, cell proliferation, cell cycle progression and resistance to chemotherapeutic drugs compared with TCF-4D clones. Capability of cell migration and colony formation was significantly higher in TCF-4C than TCF-4D clones. In a nude mice xenograft model, the HAK-1A-derived TCF-4C clone rapidly developed tumours compared with the TCF-4D clone. TCF-4C clone-derived tumours exhibited upregulation of Wnt-responsive target genes compared with the slow developing and small TCF-4D-derived tumours. CONCLUSION: These results demonstrate that the TCF-4C isoform lacking exon 4 is associated with a malignant phenotype compared with the exon 4-harbouring TCF-4D isoform, indicating that exon 4 of TCF-4 plays a prominent role in HCC development.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Proteína 2 Similar al Factor de Transcripción 7/genética , Proteína 2 Similar al Factor de Transcripción 7/metabolismo , Animales , Western Blotting , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Ensayo de Unidades Formadoras de Colonias , Exones/genética , Técnica del Anticuerpo Fluorescente , Perfilación de la Expresión Génica , Humanos , Inmunoprecipitación , Ratones , Ratones Desnudos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estadísticas no Paramétricas
9.
Can Liver J ; 6(3): 358-362, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38020188

RESUMEN

Background: Frailty is a clinical state of increased vulnerability and is common in patients with cirrhosis. The liver frailty index (LFI) is a validated tool to evaluate frailty in cirrhosis, comprising of grip strength, chair stands, and balance tests. The chair-stand test is an easy to conduct frailty subcomponent that does not require specialized equipment and may be valuable to predict adverse clinical outcomes in cirrhosis. The objective of this study was to determine if the chair-stand test is an independent predictor of mortality and hospitalization in cirrhosis. Methods: A retrospective review of 787 patients with cirrhosis was conducted. Chair-stand times were collected at baseline in person and divided into three groups: <10 seconds (n = 276), 10-15 seconds (n = 290), and >15 seconds (n = 221). Fine-Gray proportional hazards regression models were used to evaluate the association between chair-stand times and the outcomes of mortality and non-elective hospitalization. Results: The hazard of mortality (HR 3.21, 95% CI 2.16%-4.78%, p <0.001) and non-elective hospitalization (HR 2.24, 95% CI 1.73%-2.91%, p <0.001) was increased in group 3 in comparison to group 1. A chair-stand test time >15 seconds had increased all-cause mortality (HR 2.78, 95% CI 2.01%-3.83%, p <0.001) and non-elective hospitalizations (HR 1.84, 95% CI 1.48%-2.29%, p <0.001) compared to <15 seconds. Conclusions: A chair-stand test time of >15 seconds is independently associated with mortality and non-elective hospitalizations. This test holds promise as a rapid prognostication tool in cirrhosis. Future work will include external validation and virtual assessment in this population.

10.
Transplant Direct ; 7(2): e651, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33437866

RESUMEN

Frailty has emerged as a critical determinant of mortality in patients with cirrhosis. Currently, the United Network for Organ Sharing registry only includes the Karnofsky Performance Status (KPS) scale, which captures a single component of frailty. We determined the associations between frailty, as measured by the Liver Frailty Index (LFI), and KPS with waitlist mortality. METHODS: Included were 247 adult patients with cirrhosis listed for liver transplantation without hepatocellular carcinoma from February 2014 to June 2019, who underwent outpatient assessments using the LFI and KPS within 30 days of listing. "Frail" was defined using the established LFI cutoff of ≥4.4. Competing risk models assessed associations between the LFI and KPS with waitlist mortality (death/delisting for sickness). RESULTS: At a median 8 months follow-up, 25 (10%) patients died/were delisted. In this cohort, median Model for End-Stage Liver Disease-Sodium was 17, LFI was 3.9 (interquartile range 3.4-4.5), and KPS was 80 (interquartile range 70-90). In multivariable analysis, LFI (sub-hazard ratio 1.07, per 0.1 unit; 95% confidence interval, 1.01-1.12) was associated with waitlist mortality while KPS was not (sub-hazard ratio 1.00, per 10 units; 95% confidence interval, 0.78-1.29). CONCLUSIONS: Our data suggest that frailty, as measured by the LFI, may be more appropriate at capturing mortality risk than KPS and provide evidence in support of using the LFI more broadly in clinical transplant practice in the outpatient setting.

11.
Brain Res ; 1693(Pt B): 146-150, 2018 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-29903616

RESUMEN

Sensory neurons of the vagus nerve receive many different peripheral signals that can change rapidly and frequently throughout the day. The ability of these neurons to convey the vast array of nuanced information to the brain requires neuronal adaptability. In this review we discuss evidence for neural plasticity in vagal afferent neurons as a mechanism for conveying nuanced information to the brain important for the control of feeding behavior. We provide evidence that synaptic plasticity, changes in membrane conductance, and neuropeptide specification are mechanisms that allow flexibility in response to metabolic cues that can be disrupted by chronic intake of energy dense diets.


Asunto(s)
Conducta Alimentaria/fisiología , Plasticidad Neuronal/fisiología , Nervio Vago/citología , Nervio Vago/fisiología , Animales , Humanos , Neuropéptidos/metabolismo
12.
Nat Commun ; 8: 15046, 2017 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-28492243

RESUMEN

The adult mammalian cochlear sensory epithelium houses two major types of cells, mechanosensory hair cells and underlying supporting cells, and lacks regenerative capacity. Recent evidence indicates that a subset of supporting cells can spontaneously regenerate hair cells after ablation only within the first week postparturition. Here in vivo clonal analysis of mouse inner ear cells during development demonstrates clonal relationship between hair and supporting cells in sensory organs. We report the identification in mouse of a previously unknown population of multipotent stem/progenitor cells that are capable of not only contributing to the hair and supporting cells but also to other cell types, including glia, in cochlea undergoing development, maturation and repair in response to damage. These multipotent progenitors originate from Eya1-expressing otic progenitors. Our findings also provide evidence for detectable regenerative potential in the postnatal cochlea beyond 1 week of age.


Asunto(s)
Células Ciliadas Auditivas/citología , Audición/fisiología , Células Laberínticas de Soporte/citología , Células Madre Multipotentes/citología , Neuroglía/citología , Animales , Animales Recién Nacidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Biomarcadores/metabolismo , Diferenciación Celular , Embrión de Mamíferos , Femenino , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células Ciliadas Auditivas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Células Laberínticas de Soporte/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Masculino , Ratones , Células Madre Multipotentes/metabolismo , Miosina VIIa , Miosinas/genética , Miosinas/metabolismo , Neuroglía/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/metabolismo , Proteína Fluorescente Roja
13.
Mol Cell Biol ; 37(1)2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27795300

RESUMEN

EYA1 is known to be overexpressed in human breast cancer, in which the Myc protein is also accumulated in association with decreased phospho-T58 (pT58) levels. We have recently reported that EYA1 functions as a unique protein phosphatase to dephosphorylate Myc at pT58 to regulate Myc levels. However, it remains unclear whether EYA1-mediated Myc dephosphorylation on T58 is a critical function in regulating Myc protein stability in breast cancer. Furthermore, EYA1's substrate specificity has remained elusive. In this study, we have investigated these questions, and here, we report that depletion of EYA1 using short hairpin RNA (shRNA) in breast cancer cells destabilizes the Myc protein and increases pT58 levels, leading to an increase in the doubling time and impairment of cell cycle progression. In correlation with EYA1-mediated stabilization of cMyc and reduced levels of pT58, EYA1 greatly reduced cMyc-FBW7 binding and cMyc ubiquitination, thus providing novel insight into how EYA1 acts to regulate the FBW7-mediated Myc degradation machinery. We found that the conserved C-terminal haloacid dehalogenase domain of EYA1, which has been reported to have only tyrosine phosphatase activity, has dual phosphatase activities, and both the N- and C-terminal domains interact with substrates to increase the catalytic activity of EYA1. Enzymatic assay and nuclear magnetic resonance (NMR) analysis demonstrated that EYA1 has a striking conformation preference for phospho-T58 of Myc. Together, our results not only provide novel structural evidence about the conformation specificity of EYA1 in dephosphorylating phosphothreonine in Myc but also reveal an important mechanism contributing to Myc deregulation in human breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas F-Box/metabolismo , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatasas/química , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ciclo Celular , Línea Celular Tumoral , Proteína 7 que Contiene Repeticiones F-Box-WD , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Modelos Moleculares , Fosforilación , Unión Proteica , Conformación Proteica , Estabilidad Proteica , Proteínas Proto-Oncogénicas c-myc/química , Treonina/metabolismo
15.
PLoS One ; 11(5): e0154984, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27171474

RESUMEN

Mouse N-ethyl-N-nitrosourea (ENU) mutagenesis has generated many useful animal models for human diseases. Here we describe the identification of a novel ENU-induced mouse mutant strain Turner (Tur) that displays circling and headtossing behavior and progressive hearing loss. Tur/Tur homozygous animals lack Preyer and righting reflexes and display severe headtossing and reaching response defect. We mapped the Tur mutation to a critical region of 11 cM on chromosome 9 that includes myosin VI. Direct sequence analysis revealed a c.820A>T substitution in exon 8 of the Myo6 gene that changes amino acid Asn200 to Ile (p.N200I) in the motor domain. Analysis of inner ear hair cells by immunohistochemistry, scanning electron microscopy and histology revealed degeneration of hair cells in the inner ear and structural malformation of the stereocilia in the cochlea of Turner homozygous mutant mice. Our data indicate that this novel mouse strain provides a useful model for future studies on the function of myosin VI in mammalian auditory and non-auditory systems and in human syndromes.


Asunto(s)
Sordera/genética , Sordera/fisiopatología , Mutación/genética , Cadenas Pesadas de Miosina/genética , Vestíbulo del Laberinto/fisiopatología , Animales , Umbral Auditivo , Secuencia de Bases , Conducta Animal , Cromosomas de los Mamíferos/genética , Epitelio/patología , Epitelio/ultraestructura , Etilnitrosourea , Potenciales Evocados Auditivos del Tronco Encefálico , Genes Dominantes , Células Ciliadas Auditivas/patología , Células Ciliadas Auditivas/ultraestructura , Masculino , Ratones Endogámicos C57BL , Ratones Mutantes , Penetrancia , Vestíbulo del Laberinto/ultraestructura
16.
PLoS One ; 11(4): e0153550, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27092773

RESUMEN

Tumor-associated macrophages (TAMs) represent an important cellular subset within the glioblastoma (WHO grade IV) microenvironment and are a potential therapeutic target. TAMs display a continuum of different polarization states between antitumorigenic M1 and protumorigenic M2 phenotypes, with a lower M1/M2 ratio correlating with worse prognosis. Here, we investigated the effect of macrophage polarization on anti-CD47 antibody-mediated phagocytosis of human glioblastoma cells in vitro, as well as the effect of anti-CD47 on the distribution of M1 versus M2 macrophages within human glioblastoma cells grown in mouse xenografts. Bone marrow-derived mouse macrophages and peripheral blood-derived human macrophages were polarized in vitro toward M1 or M2 phenotypes and verified by flow cytometry. Primary human glioblastoma cell lines were offered as targets to mouse and human M1 or M2 polarized macrophages in vitro. The addition of an anti-CD47 monoclonal antibody led to enhanced tumor-cell phagocytosis by mouse and human M1 and M2 macrophages. In both cases, the anti-CD47-induced phagocytosis by M1 was more prominent than that for M2. Dissected tumors from human glioblastoma xenografted within NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice and treated with anti-CD47 showed a significant increase of M1 macrophages within the tumor. These data show that anti-CD47 treatment leads to enhanced tumor cell phagocytosis by both M1 and M2 macrophage subtypes with a higher phagocytosis rate by M1 macrophages. Furthermore, these data demonstrate that anti-CD47 treatment alone can shift the phenotype of macrophages toward the M1 subtype in vivo.


Asunto(s)
Anticuerpos/farmacología , Antígeno CD47/metabolismo , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Macrófagos/efectos de los fármacos , Macrófagos/patología , Fagocitosis/efectos de los fármacos , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Glioblastoma/metabolismo , Humanos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos NOD , Fenotipo
17.
Dev Cell ; 31(4): 434-47, 2014 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-25458011

RESUMEN

Self-renewal and proliferation of nephron progenitor cells and the decision to initiate nephrogenesis are crucial events directing kidney development. Despite recent advancements in defining lineage and regulators for the progenitors, fundamental questions about mechanisms driving expansion of the progenitors remain unanswered. Here we show that Eya1 interacts with Six2 and Myc to control self-renewing cell activity. Cell fate tracing reveals a developmental restriction of the Eya1(+) population within the intermediate mesoderm to nephron-forming cell fates and a common origin shared between caudal mesonephric and metanephric nephrons. Conditional inactivation of Eya1 leads to loss of Six2 expression and premature epithelialization of the progenitors. Six2 mediates translocation of Eya1 to the nucleus, where Eya1 uses its threonine phosphatase activity to control Myc phosphorylation/dephosphorylation and function in the progenitor cells. Our results reveal a functional link between Eya1, Six2, and Myc in driving the expansion and maintenance of the multipotent progenitors during nephrogenesis.


Asunto(s)
Proteínas de Homeodominio/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Nefronas/citología , Nefronas/metabolismo , Proteínas Nucleares/metabolismo , Organogénesis/fisiología , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Células Madre/citología , Factores de Transcripción/metabolismo , Animales , Diferenciación Celular/fisiología , Mesodermo/metabolismo , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Transgénicos , Células Madre/metabolismo
18.
Cancer Lett ; 336(2): 359-69, 2013 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-23562475

RESUMEN

T-cell factor (TCF) proteins represent key transcription factors in Wnt signaling. We show that the SxxSS motif in TCF-4 regulates transcriptional activity in HCC cells. TCF-4K mutants increased transcriptional activity compared to TCF-4K (bearing the SxxSS); the binding pattern of co-factors in TCF-4K mutants was similar to that in TCF-4J (lacking the SxxSS). TCF activity in TCF-4K cells was suppressed by homeodomain-interacting protein kinase 2 (HIPK2), but not in TCF-4J cells. Together, our data indicates that the SxxSS motif in TCF-4K regulates transcriptional activity by modifying co-factors in the ß-catenin/TCF-4 transcriptional complex and these events may be mediated through HIPK2.


Asunto(s)
Secuencias de Aminoácidos , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Factores de Transcripción/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Secuencia de Aminoácidos , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Carcinoma Hepatocelular/genética , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Humanos , Neoplasias Hepáticas/genética , Datos de Secuencia Molecular , Fosforilación , Isoformas de Proteínas , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Factor de Transcripción 4 , Factores de Transcripción/genética , Activación Transcripcional , Transfección , Proteínas Wnt/genética , beta Catenina/genética
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