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1.
Nucleic Acids Res ; 51(19): 10484-10505, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37697435

RESUMEN

Breast cancer linked with BRCA1/2 mutations commonly recur and resist current therapies, including PARP inhibitors. Given the lack of effective targeted therapies for BRCA1-mutant cancers, we sought to identify novel targets to selectively kill these cancers. Here, we report that loss of RNF8 significantly protects Brca1-mutant mice against mammary tumorigenesis. RNF8 deficiency in human BRCA1-mutant breast cancer cells was found to promote R-loop accumulation and replication fork instability, leading to increased DNA damage, senescence, and synthetic lethality. Mechanistically, RNF8 interacts with XRN2, which is crucial for transcription termination and R-loop resolution. We report that RNF8 ubiquitylates XRN2 to facilitate its recruitment to R-loop-prone genomic loci and that RNF8 deficiency in BRCA1-mutant breast cancer cells decreases XRN2 occupancy at R-loop-prone sites, thereby promoting R-loop accumulation, transcription-replication collisions, excessive genomic instability, and cancer cell death. Collectively, our work identifies a synthetic lethal interaction between RNF8 and BRCA1, which is mediated by a pathological accumulation of R-loops.


Asunto(s)
Proteína BRCA1 , Neoplasias de la Mama , Animales , Femenino , Humanos , Ratones , Proteína BRCA1/metabolismo , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Daño del ADN , Proteínas de Unión al ADN/metabolismo , Exorribonucleasas/metabolismo , Inestabilidad Genómica , Recurrencia Local de Neoplasia , Estructuras R-Loop , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
2.
Can Oncol Nurs J ; 34(2): 179-186, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706646

RESUMEN

Background: Approximately 82% of children with childhood cancer survive more than five years after diagnosis. Living as a cancer survivor elicits a new reality that can include psychosocial impacts. These psychosocial impacts interact collectively, especially regarding reassimilation, and are rarely explored. Objective: To explore the psychosocial impacts of surviving childhood cancer and reassimilation back into society in young adult survivors of childhood cancer. Methodology: Individual in-depth semi-structured interviews were conducted with childhood cancer survivors and explored psychosocial aspects associated with returning to work, school, and social environments after remission. Interpretive phenomenological analysis was conducted once interviews were manually transcribed. A group interview with survivors was held to discuss the study's findings and interpretation. Results: Individual interviews and the group interview revealed three major themes: outlook on reassimilating, outlook on coping, and outlook on cancer. Conclusions: This work is a first step to understanding how survivors' personal outlook on coping and healthcare system barriers play influential roles in reassimilation following cancer treatment. Survivors expressed the need for reliable survivorship information and improved communication with healthcare providers regarding what to expect, so they could feel prepared for life post-cancer. These aspects need to be explored more deeply through other qualitative studies.

3.
J Gen Intern Med ; 34(10): 2062-2067, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31388904

RESUMEN

BACKGROUND: Venous thromboembolism includes deep vein thrombosis (DVT) and pulmonary embolism. Compression ultrasonography is the most common way to evaluate DVT and is typically performed by sonographers and interpreted by radiologists. Yet there is evidence that ultrasound examinations can be safely and accurately performed by clinicians at the bedside. OBJECTIVE: To measure the operating characteristics of hospital medicine providers performing point-of-care ultrasound (POCUS) for evaluation of DVT. DESIGN: This is a prospective cohort study enrolling a convenience sample of patients. Hospital medicine providers performed POCUS for DVT and the results were compared with the corresponding formal vascular study (FVS) interpreted by radiologists. PARTICIPANTS: Hospitalized non-ICU patients at four tertiary care hospitals for whom a DVT ultrasound was ordered. MAIN MEASURES: The primary outcomes were the sensitivity, specificity, and predictive values of the POCUS compression ultrasound compared with a FVS. The secondary outcome was the elapsed time between order and the POCUS study compared with the time the FVS was ordered to when the formal radiology report was finalized. KEY RESULTS: One hundred twenty-five limbs from 73 patients were scanned. The prevalence of DVT was 6.4% (8/125). The sensitivity of POCUS for DVT was 100% (95% CI 74-100%) and specificity was 95.8% (95% CI 91-98%) with a positive predictive value of 61.5% (95% CI 35-84%) and a negative predictive value of 100% (95% CI 98-100%). The median time from order to POCUS completion was 5.8 h versus 11.5 h median time from order until the radiology report was finalized (p = 0.001). CONCLUSION: Hospital medicine providers can perform compression-only POCUS for DVT on inpatients with accuracy similar to other specialties and settings, with results available sooner than radiology. The observed prevalence of DVT was lower than expected. POCUS may be reliable in excluding DVT but further study is required to determine how to incorporate a positive POCUS DVT result into clinical practice.


Asunto(s)
Médicos Hospitalarios/normas , Pruebas en el Punto de Atención/organización & administración , Ultrasonografía/métodos , Trombosis de la Vena/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Factores de Tiempo
5.
Am J Transplant ; 18(10): 2534-2543, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29498216

RESUMEN

Incidence of postdonation hypertension, risk factors associated with its development, and impact of type of treatment received on renal outcomes were determined in 3700 kidney donors. Using Cox proportional hazard model, adjusted hazard ratios (HRs) for cardiovascular disease (CVD); estimated glomerular filtration rate (eGFR) <60, <45, <30 mL/min/1.73m2 ; end stage renal disease (ESRD); and death in hypertensive donors were determined. After a mean (standard deviation [SD]) of 16.6 (11.9) years of follow-up, 1126 (26.8%) donors developed hypertension and 894 with known antihypertensive medications. Hypertension developed in 4%, 10%, and 51% at 5, 10, and 40 years, respectively, and was associated with proteinuria, eGFR < 30, 45, and 60 mL/min/1.73m2 , CVD, and death. Blood pressure was <140/90 mm Hg at last follow-up in 75% of hypertensive donors. Use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (compared to other antihypertensive agents) was associated with a lower risk for eGFR <45 mL/min/1.73m², HR 0.64 (95% confidence interval [CI] 0.45-0.9), P = .01, and also less ESRD; HR 0.03 (95% CI 0.001-0.20), P = .004. In this predominantly Caucasian cohort, hypertension is common after donation, well controlled in most donors, and factors associated with its development are similar to those in the general population.


Asunto(s)
Hipertensión/epidemiología , Riñón/fisiopatología , Donadores Vivos/provisión & distribución , Nefrectomía/efectos adversos , Complicaciones Posoperatorias , Recolección de Tejidos y Órganos/efectos adversos , Adulto , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/etiología , Incidencia , Trasplante de Riñón , Estudios Longitudinales , Masculino , Pronóstico , Factores de Riesgo , Estados Unidos/epidemiología
6.
Clin Transplant ; 32(9): e13360, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30053320

RESUMEN

In the general population, obesity is associated with an increased risk of developing hypertension (HTN), type 2 diabetes mellitus (DM), and end-stage renal disease (ESRD). Therefore, most transplant centers have a body mass index (BMI) threshold for accepting living kidney donors. But there have been no studies of postdonation weight gain trends and any associated risks. We tracked serial BMIs in 940 donors for a median (IQ range) follow-up of 22.3 (15.4-35.8) years. We studied the impact of postdonation weight gain in a model adjusted for family history of HTN or DM. Donor characteristics included age, sex, smoking, fasting blood glucose, eGFR, systolic and diastolic BP, and BMI at time of donation and time postdonation. Postdonation weight gain was associated with a significant increase in the relative risk of developing HTN RR 1.93 (95% CI 1.51-2.46) (P < 0.001) and/or DM RR 4.18 (95% CI 2.05-8.5) (P < 0.0001), but not (to date) cardiovascular disease (CVD), reduced eGFR or death. Like the general population, donors gained weight as they aged; a higher BMI was associated with higher incidence of DM and HTN. Postdonation care should include ongoing counseling on the risks of substantial weight gain.


Asunto(s)
Diabetes Mellitus Tipo 2/etiología , Hipertensión/etiología , Donadores Vivos/provisión & distribución , Nefrectomía/efectos adversos , Obesidad/etiología , Recolección de Tejidos y Órganos/efectos adversos , Aumento de Peso , Adulto , Índice de Masa Corporal , Femenino , Estudios de Seguimiento , Humanos , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo
7.
Arterioscler Thromb Vasc Biol ; 37(12): 2370-2378, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29025708

RESUMEN

OBJECTIVE: Excess deposition of fat within and around vital organs and nonadipose tissues is hypothesized to contribute to cardiovascular disease (CVD) risk. We evaluated the association of abdominal intermuscular adipose tissue (IMAT) volume with coronary artery calcification in the CARDIA study (Coronary Artery Risk Development in Young Adults) participants. APPROACH AND RESULTS: We measured IMAT in the abdominal muscles, visceral adipose tissue and pericardial adipose tissue, and coronary artery calcification using computed tomography in 3051 CARDIA participants (56% women) at the CARDIA year 25 examination (2010-2011). Mean IMAT volume and mean IMAT/total muscle volume (IMAT normalized for muscle size) were calculated in a 10-mm block of slices centered at L3-L4. Multivariable analyses included potential confounders and traditional cardiovascular disease risk factors. Compared with the lowest quartile, the upper quartile of abdominal IMAT volume was associated with higher coronary artery calcification prevalence (odds ratio [95% confidence interval], 1.6 [1.2-2.1]) after adjusting for cardiovascular disease risk factors. Results were similar for highest versus lowest quartile of IMAT normalized to total muscle volume (odds ratio [95% confidence interval], 1.5 [1.1-2.0]). Significant associations of higher IMAT and normalized IMAT with coronary artery calcification prevalence persisted when body mass index, visceral adipose tissue, or pericardial adipose tissue were added to the models. CONCLUSIONS: In a large, community-based, cross-sectional study, we found that higher abdominal skeletal muscle adipose tissue volume was associated with subclinical atherosclerosis independent of traditional cardiovascular disease risk factors and other adipose depots.


Asunto(s)
Músculos Abdominales/fisiopatología , Adiposidad , Enfermedad de la Arteria Coronaria/epidemiología , Grasa Intraabdominal/fisiopatología , Calcificación Vascular/epidemiología , Músculos Abdominales/diagnóstico por imagen , Adolescente , Adulto , Factores de Edad , Enfermedades Asintomáticas , Angiografía por Tomografía Computarizada , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Estudios Transversales , Femenino , Humanos , Grasa Intraabdominal/diagnóstico por imagen , Modelos Logísticos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Análisis Multivariante , Oportunidad Relativa , Pericardio/diagnóstico por imagen , Pericardio/fisiopatología , Prevalencia , Factores de Riesgo , Estados Unidos/epidemiología , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/fisiopatología , Adulto Joven
8.
Clin Chem ; 63(7): 1237-1247, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28515098

RESUMEN

BACKGROUND: Sustained remodeling of extracellular matrix can compromise organs and tissues. Procollagen type III N-terminal propeptide (PIIINP) and collagen type I carboxy-terminal telopeptide (ICTP) reflect collagen synthesis and degradation. We studied their predictive value for future death and disease. METHODS: A total of 3068 men and women in the Multi-Ethnic Study of Atherosclerosis who were free of cardiovascular disease (CVD) and in generally good health had a baseline blood sample taken for ICTP and PIIINP. Median follow-up was 13.0 years. Among 4 primary outcomes, CVD events (n = 697) were adjudicated, death (n = 571) was by death certificate, and chronic inflammatory-related severe hospitalization and death (ChrIRD, n = 726) and total cancer (n = 327) were classified using International Classification of Diseases codes. We used Poisson regression to study baseline ICTP and PIIINP relative to these outcomes. RESULTS: Mean (SD) PIIINP was 5.47 (1.95) µg/L and ICTP was 3.37 (1.70) µg/L. PIIINP and ICTP were highly correlated with each other and with estimated glomerular filtration rate (eGFR). Adjustment for age and eGFR attenuated relative risks, remaining 20%-30% per SD of both PIIINP and ICTP in prediction for total death and ChrIRD, and of PIIINP for cancer, with little additional attenuation by adjusting for risk factors and inflammatory biomarkers. CVD outcome was generally unrelated to PIIINP but became marginally inversely related to ICTP in the most adjusted model. CONCLUSIONS: The collagen biomarkers PIIINP and ICTP, in part through pathophysiologically parallel associations with renal function, predicted ChrIRD and total death. Moreover, PIIINP predicted future cancer. These collagen markers may help differentiate healthy from unhealthy aging.


Asunto(s)
Aterosclerosis/diagnóstico , Aterosclerosis/etnología , Biomarcadores/sangre , Enfermedades Cardiovasculares/diagnóstico , Colágeno/sangre , Valor Predictivo de las Pruebas , Aterosclerosis/sangre , Enfermedades Cardiovasculares/sangre , Colágeno/metabolismo , Colágeno Tipo I/sangre , Etnicidad/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Neoplasias/diagnóstico , Fragmentos de Péptidos/sangre , Péptidos/sangre , Procolágeno/sangre
9.
Clin Chem ; 62(7): 1020-31, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27173011

RESUMEN

BACKGROUND: GlycA is a biomarker that reflects integrated concentrations and glycosylation states of several acute-phase proteins. We studied the association of GlycA and inflammatory biomarkers with future death and disease. METHODS: A total of 6523 men and women in the Multi-Ethnic Study of Atherosclerosis who were free of overt cardiovascular disease (CVD) and in generally good health had a baseline blood sample taken. We assayed high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and d-dimer. A spectral deconvolution algorithm was used to quantify GlycA signal amplitudes from automated nuclear magnetic resonance (NMR) LipoProfile® test spectra. Median follow-up was 12.1 years. Among 4 primary outcomes, CVD events were adjudicated, death was by death certificate, and chronic inflammatory-related severe hospitalization and death (ChrIRD) and total cancer were classified using International Classification of Diseases (ICD) codes. We used Poisson regression to study baseline GlycA, hsCRP, IL-6, and d-dimer in relation to total death, CVD, ChrIRD, and total cancer. RESULTS: Relative risk per SD of GlycA, IL-6, and d-dimer for total death (n = 915); for total CVD (n = 922); and for ChrIRD (n = 1324) ranged from 1.05 to 1.20, independently of covariates. In contrast, prediction from hsCRP was statistically explained by adjustment for other inflammatory variables. Only GlycA was predictive for total cancer (n = 663). Women had 7% higher values of all inflammatory biomarkers than men and had a significantly lower GlycA prediction coefficient than men in predicting total cancer. CONCLUSIONS: The composite biomarker GlycA derived from NMR is associated with risk for total death, CVD, ChrIRD, and total cancer after adjustment for hsCRP, IL-6, and d-dimer. IL-6 and d-dimer contribute information independently of GlycA.


Asunto(s)
Proteínas de Fase Aguda/análisis , Aterosclerosis/sangre , Certificado de Defunción , Inflamación/sangre , Neoplasias/sangre , Anciano , Anciano de 80 o más Años , Algoritmos , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas
10.
Cardiovasc Diabetol ; 15: 51, 2016 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-27013319

RESUMEN

BACKGROUND: Oxidative stress, inflammation and endothelial dysfunction are interrelated factors in the etiology of cardiovascular disease, but their linkage to type 2 diabetes is less clear. We examined the association of these biomarkers with incident type 2 diabetes (T2D). METHODS: Analysis of 2339 participants in the community-based coronary artery risk development in young adults (CARDIA) study. Participants (age 40.1 ± 3.6 years, 44 % Black, 58 % women) were free of diabetes, and were followed 10 years. Cox regression was used to estimate hazard ratios (HRs) for incident T2D adjusting for the other biomarkers under study, demographic and lifestyle measures, dietary biomarkers, BMI (kg/m(2)) and metabolic syndrome components. RESULTS: F2-isoprostanes and oxidized LDL (oxidative stress) were positively associated with incident T2D, but the associations were attenuated by adjustment for BMI. C-reactive protein was positively associated with T2D even with full adjustment: HR (95 % CI) = 2.21 (1.26-3.88) for quartile 4 (Q4) v. quartile 1 (Q1). The HR (95 % CI) for T2D for biomarkers of endothelial dysfunction ICAM-1 and E-selectin for Q4 v. Q1 were 1.64 (0.96-2.81) and 1.68 (1.04-2.71) respectively, with full adjustment. Including these two markers in a common risk score incorporating BMI and clinical measures improved the prediction probability of T2D: relative risk for the average person classified up compared to the average person classified down: 1.09, (1.06-1.13), P < 0.0001. CONCLUSIONS: Biomarkers of inflammation and endothelial dysfunction were positively associated with incident T2D. ICAM-1 and E-selectin add to the prediction of T2D beyond a common risk score.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/metabolismo , Endotelio/fisiopatología , Estrés Oxidativo/fisiología , Adulto , Biomarcadores/metabolismo , Población Negra , Proteína C-Reactiva/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Inflamación/complicaciones , Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Factores de Riesgo
11.
PLoS Genet ; 9(1): e1003259, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23382699

RESUMEN

Rnf8 is an E3 ubiquitin ligase that plays a key role in the DNA damage response as well as in the maintenance of telomeres and chromatin remodeling. Rnf8(-/-) mice exhibit developmental defects and increased susceptibility to tumorigenesis. We observed that levels of p53, a central regulator of the cellular response to DNA damage, increased in Rnf8(-/-) mice in a tissue- and cell type-specific manner. To investigate the role of the p53-pathway inactivation on the phenotype observed in Rnf8(-/-) mice, we have generated Rnf8(-/-)p53(-/-) mice. Double-knockout mice showed similar growth retardation defects and impaired class switch recombination compared to Rnf8(-/-) mice. In contrast, loss of p53 fully rescued the increased apoptosis and reduced number of thymocytes and splenocytes in Rnf8(-/-) mice. Similarly, the senescence phenotype of Rnf8(-/-) mouse embryonic fibroblasts was rescued in p53 null background. Rnf8(-/-)p53(-/-) cells displayed defective cell cycle checkpoints and DNA double-strand break repair. In addition, Rnf8(-/-)p53(-/-) mice had increased levels of genomic instability and a remarkably elevated tumor incidence compared to either Rnf8(-/-) or p53(-/-) mice. Altogether, the data in this study highlight the importance of p53-pathway activation upon loss of Rnf8, suggesting that Rnf8 and p53 functionally interact to protect against genomic instability and tumorigenesis.


Asunto(s)
Transformación Celular Neoplásica/genética , Neoplasias , Proteína p53 Supresora de Tumor , Ubiquitina-Proteína Ligasas , Animales , Transformación Celular Neoplásica/metabolismo , Ensamble y Desensamble de Cromatina/genética , Roturas del ADN de Doble Cadena , Daño del ADN , Reparación del ADN/genética , Fibroblastos/citología , Inestabilidad Genómica , Humanos , Ratones , Ratones Noqueados , Neoplasias/genética , Neoplasias/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
12.
Am Heart J ; 170(6): 1170-83, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26678639

RESUMEN

BACKGROUND: N-terminal-pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (TnT) predict cardiovascular disease (CVD) risk in a variety of populations. Whether their predictive value varies by ethnicity is unknown. We sought to determine whether NT-proBNP and TnT improve prediction of incident coronary heart disease (CHD) and CVD, independent of CVD risk factors, in a multiethnic population; whether NT-proBNP improves prediction compared with the Framingham Risk Score or the Pooled Cohort Risk Equation; and whether a second NT-proBNP further improves prediction. METHODS: Both NT-proBNP and TnT were measured in 5,592 MESA white, black, Hispanic, and Chinese participants (60% nonwhite; mean age 62.3 ± 10.3 years) in 2000 to 2002 and 2004 to 2005. We evaluated adjusted risk of incident CHD and CVD based on baseline and change in biomarker concentration. RESULTS: Participants were followed up through 2011 and incurred 370 CVD events (232 CHD). Concentrations of NT-proBNP and TnT varied by ethnicity. Both NT-proBNP and TnT were associated with an increased risk of events (adjusted hazard ratio [HR] for CHD [95% CI] for fifth quintile vs other 4 quintiles of NT-proBNP, 2.03 [1.50-2.76]; HR for CHD for detectable vs undetectable TnT, 3.95 [2.29-6.81]). N-terminal-pro-B-type natriuretic peptide improved risk prediction and classification compared with the Framingham Risk Score and the Pooled Cohort Risk Equation. Change in NT-proBNP was independently associated with events (HR for CHD per unit increase in ΔlogNT-proBNP, 1.95 [1.16-3.26]). None of the observed associations varied by ethnicity. CONCLUSIONS: Both NT-proBNP and TnT are predictors of incident CHD, independent of established risk factors and ethnicity, in a multiethnic population without known CVD. Change in NT-proBNP may add additional prognostic information.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Troponina T/sangre , Anciano , Anciano de 80 o más Años , Aterosclerosis/sangre , Aterosclerosis/diagnóstico , Aterosclerosis/etnología , Biomarcadores/sangre , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Etnicidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Medición de Riesgo/métodos , Factores de Riesgo , Estados Unidos/epidemiología
13.
Blood ; 119(15): 3495-502, 2012 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-22343728

RESUMEN

In addition to its proapoptotic function, caspase-8 is also important for several other processes, including suppressing necroptosis, cell migration, and immune cell survival. In the present study, we report that the loss of caspase-8 in B lymphocytes leads to B-cell malignancies and that the risk for these tumors is further enhanced in the absence of p53. We also report that deficiency of caspase-8 results in impaired cytokinesis and that casp8(-/-) lymphomas display remarkably elevated levels of chromosomal aberrations. Our data support an important role for caspase-8 in the maintenance of genomic integrity and highlight its tumor-suppressive function.


Asunto(s)
Caspasa 8/fisiología , Inestabilidad Cromosómica/genética , Linfoma de Células B/genética , Células 3T3 , Animales , Síndrome Linfoproliferativo Autoinmune/complicaciones , Síndrome Linfoproliferativo Autoinmune/genética , Síndrome Linfoproliferativo Autoinmune/inmunología , Síndrome Linfoproliferativo Autoinmune/patología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos B/fisiología , Caspasa 8/genética , Células Cultivadas , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Genes p53/fisiología , Predisposición Genética a la Enfermedad , Linfoma de Células B/etiología , Linfoma de Células B/mortalidad , Linfoma de Células B/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Análisis de Supervivencia
14.
PLoS Genet ; 7(4): e1001381, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21552324

RESUMEN

Eukaryotic cells have evolved to use complex pathways for DNA damage signaling and repair to maintain genomic integrity. RNF168 is a novel E3 ligase that functions downstream of ATM,γ-H2A.X, MDC1, and RNF8. It has been shown to ubiquitylate histone H2A and to facilitate the recruitment of other DNA damage response proteins, including 53BP1, to sites of DNA break. In addition, RNF168 mutations have been causally linked to the human RIDDLE syndrome. In this study, we report that Rnf168(-/-) mice are immunodeficient and exhibit increased radiosensitivity. Rnf168(-/-) males suffer from impaired spermatogenesis in an age-dependent manner. Interestingly, in contrast to H2a.x(-/-), Mdc1(-/-), and Rnf8(-/-) cells, transient recruitment of 53bp1 to DNA double-strand breaks was abolished in Rnf168(-/-) cells. Remarkably, similar to 53bp1 inactivation, but different from H2a.x deficiency, inactivation of Rnf168 impairs long-range V(D)J recombination in thymocytes and results in long insertions at the class-switch junctions of B-cells. Loss of Rnf168 increases genomic instability and synergizes with p53 inactivation in promoting tumorigenesis. Our data reveal the important physiological functions of Rnf168 and support its role in both γ-H2a.x-Mdc1-Rnf8-dependent and -independent signaling pathways of DNA double-strand breaks. These results highlight a central role for RNF168 in the hierarchical network of DNA break signaling that maintains genomic integrity and suppresses cancer development in mammals.


Asunto(s)
Roturas del ADN de Doble Cadena , Inestabilidad Genómica , Espermatogénesis/genética , Ubiquitina-Proteína Ligasas/genética , Factores de Edad , Animales , Proteínas Cromosómicas no Histona/metabolismo , Reparación del ADN , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Femenino , Cambio de Clase de Inmunoglobulina/genética , Masculino , Ratones , Ratones Noqueados , Ratones Mutantes , Neoplasias/genética , Tolerancia a Radiación , Recombinación Genética , Transducción de Señal , Síndrome , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53 , Ubiquitina-Proteína Ligasas/metabolismo
15.
PLoS Genet ; 7(11): e1002360, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22125490

RESUMEN

Ubiquitylation is fundamental for the regulation of the stability and function of p53 and c-Myc. The E3 ligase Pirh2 has been reported to polyubiquitylate p53 and to mediate its proteasomal degradation. Here, using Pirh2 deficient mice, we report that Pirh2 is important for the in vivo regulation of p53 stability in response to DNA damage. We also demonstrate that c-Myc is a novel interacting protein for Pirh2 and that Pirh2 mediates its polyubiquitylation and proteolysis. Pirh2 mutant mice display elevated levels of c-Myc and are predisposed for plasma cell hyperplasia and tumorigenesis. Consistent with the role p53 plays in suppressing c-Myc-induced oncogenesis, its deficiency exacerbates tumorigenesis of Pirh2(-/-) mice. We also report that low expression of human PIRH2 in lung, ovarian, and breast cancers correlates with decreased patients' survival. Collectively, our data reveal the in vivo roles of Pirh2 in the regulation of p53 and c-Myc stability and support its role as a tumor suppressor.


Asunto(s)
Neoplasias/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Transformación Celular Neoplásica , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Células HEK293 , Humanos , Estimación de Kaplan-Meier , Ratones , Ratones Endogámicos C57BL , Neoplasias/genética , Proteolisis , Proteínas Proto-Oncogénicas c-myc/genética , Tolerancia a Radiación , Proteína p53 Supresora de Tumor/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación/genética
16.
Nat Genet ; 36(9): 969-77, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15322543

RESUMEN

Tumor-necrosis factor (TNF), a pleiotropic cytokine, triggers physiological and pathological responses in several organs. Here we show that deletion of the mouse gene Timp3 resulted in an increase in TNF-alpha converting enzyme activity, constitutive release of TNF and activation of TNF signaling in the liver. The increase in TNF in Timp3(-/-) mice culminated in hepatic lymphocyte infiltration and necrosis, features that are also seen in chronic active hepatitis in humans. This pathology was prevented when deletion of Timp3 was combined with Tnfrsf1a deficiency. In a liver regeneration model that requires TNF signaling, Timp3(-/-) mice succumbed to liver failure. Hepatocytes from Timp3(-/-) mice completed the cell cycle but then underwent cell death owing to sustained activation of TNF. This hepatocyte cell death was completely rescued by a neutralizing antibody to TNF. Dysregulation of TNF occurred specifically in Timp3(-/-), and not Timp1(-/-) mice. These data indicate that TIMP3 is a crucial innate negative regulator of TNF in both tissue homeostasis and tissue response to injury.


Asunto(s)
Hepatitis Crónica/genética , Regeneración Hepática/genética , Proteínas/genética , Factor de Necrosis Tumoral alfa/genética , Proteínas ADAM , Proteína ADAM17 , Envejecimiento , Animales , Apoptosis , Ciclo Celular/genética , Hepatectomía , Hígado/enzimología , Hígado/patología , Metaloendopeptidasas/metabolismo , Ratones , Ratones Mutantes , Transducción de Señal , Inhibidores Tisulares de Metaloproteinasas , Factor de Necrosis Tumoral alfa/inmunología , Inhibidor Tisular de Metaloproteinasa-4
17.
Artículo en Inglés | MEDLINE | ID: mdl-37623133

RESUMEN

BACKGROUND: Uncorrected refractive error has been suggested to affect children's development, educational performance, and socialization. Sociodemographic and environmental differences among individuals may impact their accessibility to utilizing appropriate services, impacting their vision-dependent activities. METHODS: Guided by the population health framework, this retrospective study assessed the prevalence of self-reported vision correction needs and its determinants for a sample of adolescents (n = 6363) from the United Arab Emirates (UAE) aged 13 to 20 years between 2007 to 2009. RESULTS: The findings suggest a relatively high prevalence of self-reported vision correction needs (26.8%), with among 24.8% males and 31.7% among females. Factors that were significantly associated with vision correction needs included age, biological sex, location of residence (emirate), nationality, parental education and employment level, household financial status, screen time use, visiting an eye specialist in the past year, and daily functional capacity. CONCLUSION: Reporting the vision correction needs of the adolescent population and identifying its determinants may help identify and resolve modifiable barriers to accessing the appropriate vision care resources. Further research in assessing the type of refractive error, potential genetic and environmental factors, and vision care services in each emirate may help decision-makers set appropriate policies to improve the overall quality of eye health.


Asunto(s)
Rendimiento Académico , Errores de Refracción , Niño , Femenino , Masculino , Adolescente , Humanos , Estudios Transversales , Emiratos Árabes Unidos/epidemiología , Estudios Retrospectivos , Errores de Refracción/epidemiología , Errores de Refracción/terapia
18.
Nature ; 440(7084): 692-6, 2006 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-16572175

RESUMEN

Bone metastases are a frequent complication of many cancers that result in severe disease burden and pain. Since the late nineteenth century, it has been thought that the microenvironment of the local host tissue actively participates in the propensity of certain cancers to metastasize to specific organs, and that bone provides an especially fertile 'soil'. In the case of breast cancers, the local chemokine milieu is now emerging as an explanation for why these tumours preferentially metastasize to certain organs. However, as the inhibition of chemokine receptors in vivo only partially blocks metastatic behaviour, other factors must exist that regulate the preferential metastasis of breast cancer cells. Here we show that the cytokine RANKL (receptor activator of NF-kappaB ligand) triggers migration of human epithelial cancer cells and melanoma cells that express the receptor RANK. RANK is expressed on cancer cell lines and breast cancer cells in patients. In a mouse model of melanoma metastasis, in vivo neutralization of RANKL by osteoprotegerin results in complete protection from paralysis and a marked reduction in tumour burden in bones but not in other organs. Our data show that local differentiation factors such as RANKL have an important role in cell migration and the tissue-specific metastatic behaviour of cancer cells.


Asunto(s)
Neoplasias Óseas/metabolismo , Neoplasias Óseas/secundario , Proteínas Portadoras/metabolismo , Movimiento Celular , Glicoproteínas de Membrana/metabolismo , Metástasis de la Neoplasia/patología , Animales , Neoplasias Óseas/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteínas Portadoras/genética , Muerte Celular , Diferenciación Celular , Línea Celular Tumoral , Proliferación Celular , Células Epiteliales/patología , Femenino , Humanos , Melanoma/metabolismo , Melanoma/patología , Glicoproteínas de Membrana/genética , Ratones , Especificidad de Órganos , Parálisis , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B , Transducción de Señal
19.
Discov Educ ; 1(1): 3, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35795020

RESUMEN

The rapid adoption of online technologies to deliver postsecondary education amid the COVID-19 pandemic has highlighted the potential for online learning, as well as important equity gaps to be addressed. For over ten years, McMaster University has delivered graduate global health education through a blended-learning approach. In partnership with universities in the Netherlands, India, Thailand, Norway, Colombia, and Sudan, experts from across the Consortium deliver lectures online to students around the world. In 2020, two courses were piloted with small groups of students from Canada and Colombia using machine translation supported by bilingual tutors. Students met weekly via video conferencing software, speaking in English and Spanish and relying on machine translation software to transcribe and translate for group members. Qualitative semi-structured interviews were conducted with students, tutors, and instructors to explore how artificial intelligence can be harnessed to integrate multilingual group work into course offerings, challenging the dominant use of English as the principal language of instruction in global health education. Findings highlight the potential for machine translation to bridge language divides, while also underscoring several key limitations of currently available technology. Further research is needed to investigate the potential for machine translation in facilitating multilingual online education as a pathway to more equitable and inclusive online learning environments.

20.
Biochemistry ; 50(27): 6102-12, 2011 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-21661747

RESUMEN

Nonenzymatic modification of proteins in hyperglycemia is a major mechanism causing diabetic complications. These modifications can have pathogenic consequences when they target active site residues, thus affecting protein function. In the present study, we examined the role of glucose autoxidation in functional protein damage using lysozyme and RGD-α3NC1 domain of collagen IV as model proteins in vitro. We demonstrated that glucose autoxidation induced inhibition of lysozyme activity as well as NC1 domain binding to α(V)ß(3) integrin receptor via modification of critical arginine residues by reactive carbonyl species (RCS) glyoxal (GO) and methylglyoxal while nonoxidative glucose adduction to the protein did not affect protein function. The role of RCS in protein damage was confirmed using pyridoxamine which blocked glucose autoxidation and RCS production, thus protecting protein function, even in the presence of high concentrations of glucose. Glucose autoxidation may cause protein damage in vivo since increased levels of GO-derived modifications of arginine residues were detected within the assembly interface of collagen IV NC1 domains isolated from renal ECM of diabetic rats. Since arginine residues are frequently present within protein active sites, glucose autoxidation may be a common mechanism contributing to ECM protein functional damage in hyperglycemia and oxidative environment. Our data also point out the pitfalls in functional studies, particularly in cell culture experiments, that involve glucose treatment but do not take into account toxic effects of RCS derived from glucose autoxidation.


Asunto(s)
Arginina/metabolismo , Glucosa/fisiología , Proteínas/antagonistas & inhibidores , Proteínas/fisiología , Secuencias de Aminoácidos , Animales , Colágeno Tipo IV/antagonistas & inhibidores , Colágeno Tipo IV/química , Colágeno Tipo IV/metabolismo , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Experimental/metabolismo , Glioxal/efectos adversos , Hiperglucemia/enzimología , Hiperglucemia/metabolismo , Masculino , Micrococcus/enzimología , Muramidasa/antagonistas & inhibidores , Muramidasa/metabolismo , Carbonilación Proteica , Estructura Terciaria de Proteína , Proteínas/metabolismo , Piruvaldehído/efectos adversos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
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