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1.
Blood ; 138(10): 898-911, 2021 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-34019641

RESUMEN

Germline pathogenic TERT variants are associated with short telomeres and an increased risk of developing myelodysplastic syndrome (MDS) among patients with a telomere biology disorder. We identified TERT rare variants in 41 of 1514 MDS patients (2.7%) without a clinical diagnosis of a telomere biology disorder who underwent allogeneic transplantation. Patients with a TERT rare variant had shorter telomere length (P < .001) and younger age at MDS diagnosis (52 vs 59 years, P = .03) than patients without a TERT rare variant. In multivariable models, TERT rare variants were associated with inferior overall survival (P = .034) driven by an increased incidence of nonrelapse mortality (NRM; P = .015). Death from a noninfectious pulmonary cause was more frequent among patients with a TERT rare variant. Most variants were missense substitutions and classified as variants of unknown significance. Therefore, we cloned all rare missense variants and quantified their impact on telomere elongation in a cell-based assay. We found that 90% of TERT rare variants had severe or intermediate impairment in their capacity to elongate telomeres. Using a homology model of human TERT bound to the shelterin protein TPP1, we inferred that TERT rare variants disrupt domain-specific functions, including catalysis, protein-RNA interactions, and recruitment to telomeres. Our results indicate that the contribution of TERT rare variants to MDS pathogenesis and NRM risk is underrecognized. Routine screening for TERT rare variants in MDS patients regardless of age or clinical suspicion may identify clinically inapparent telomere biology disorders and improve transplant outcomes through risk-adapted approaches.


Asunto(s)
Variación Genética , Síndromes Mielodisplásicos , Telomerasa/genética , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Síndromes Mielodisplásicos/enzimología , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/mortalidad , Tasa de Supervivencia
2.
Blood ; 136(26): 3070-3081, 2020 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-33367544

RESUMEN

Allogeneic hematopoietic stem cell transplantation is the only potentially curative treatment for patients with myelodysplastic syndrome (MDS), but long-term survival is limited by the risk of transplant-related complications. Short telomere length, mediated by inherited or acquired factors, impairs cellular response to genotoxic and replicative stress and could identify patients at higher risk for toxicity after transplantation. We measured relative telomere length in pretransplant recipient blood samples in 1514 MDS patients and evaluated the association of telomere length with MDS disease characteristics and transplantation outcomes. Shorter telomere length was significantly associated with older age, male sex, somatic mutations that impair the DNA damage response, and more severe pretransplant cytopenias, but not with bone marrow blast count, MDS treatment history, or history of prior cancer therapy. Among 1267 patients ≥40 years old, telomere length in the shortest quartile was associated with inferior survival (P < .001) because of a high risk of nonrelapse mortality (NRM; P = .001) after adjusting for significant clinical and genetic variables. The adverse impact of shorter telomeres on NRM was independent of recipient comorbidities and was observed selectively among patients receiving more intensive conditioning, including myeloablative regimens and higher dose melphalan-based reduced-intensity regimens. The effect of shorter telomeres on NRM was prominent among patients who developed severe acute graft-versus-host disease, suggesting that short telomere length may limit regenerative potential of mucosal tissues after acute injury. MDS patients with shorter telomere length, who have inferior survival driven by excess toxicity, could be considered for strategies focused on minimizing toxic effects of transplantation.


Asunto(s)
Síndromes Mielodisplásicos , Trasplante de Células Madre , Homeostasis del Telómero , Telómero , Acondicionamiento Pretrasplante , Adulto , Anciano , Aloinjertos , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/metabolismo , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/terapia , Valor Predictivo de las Pruebas , Tasa de Supervivencia , Telómero/genética , Telómero/metabolismo
3.
Int J Cancer ; 148(2): 307-319, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-32851660

RESUMEN

Blood lipids have been associated with the development of a range of cancers, including breast, lung and colorectal cancer. For endometrial cancer, observational studies have reported inconsistent associations between blood lipids and cancer risk. To reduce biases from unmeasured confounding, we performed a bidirectional, two-sample Mendelian randomization analysis to investigate the relationship between levels of three blood lipids (low-density lipoprotein [LDL] and high-density lipoprotein [HDL] cholesterol, and triglycerides) and endometrial cancer risk. Genetic variants associated with each of these blood lipid levels (P < 5 × 10-8 ) were identified as instrumental variables, and assessed using genome-wide association study data from the Endometrial Cancer Association Consortium (12 906 cases and 108 979 controls) and the Global Lipids Genetic Consortium (n = 188 578). Mendelian randomization analyses found genetically raised LDL cholesterol levels to be associated with lower risks of endometrial cancer of all histologies combined, and of endometrioid and non-endometrioid subtypes. Conversely, higher genetically predicted HDL cholesterol levels were associated with increased risk of non-endometrioid endometrial cancer. After accounting for the potential confounding role of obesity (as measured by genetic variants associated with body mass index), the association between genetically predicted increased LDL cholesterol levels and lower endometrial cancer risk remained significant, especially for non-endometrioid endometrial cancer. There was no evidence to support a role for triglycerides in endometrial cancer development. Our study supports a role for LDL and HDL cholesterol in the development of non-endometrioid endometrial cancer. Further studies are required to understand the mechanisms underlying these findings.


Asunto(s)
HDL-Colesterol/sangre , LDL-Colesterol/sangre , Neoplasias Endometriales/sangre , Triglicéridos/sangre , Estudios de Casos y Controles , HDL-Colesterol/genética , LDL-Colesterol/genética , Neoplasias Endometriales/genética , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Análisis de la Aleatorización Mendeliana , Riesgo , Triglicéridos/genética
4.
Bipolar Disord ; 21(3): 194-214, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30887632

RESUMEN

OBJECTIVES: Functional impairment is an important driver of disability in patients with bipolar disorder (BD) and can persist even when symptomatic remission has been achieved. The objectives of this systematic literature review were to identify studies that assessed functioning in patients with BD and describe the functional scales used and their implementation. METHODS: A systematic literature review of English-language articles published between 2000 and 2017 reporting peer-reviewed, original research related to functional assessment in patients with BD was conducted. RESULTS: A total of 40 articles met inclusion criteria. Twenty-four different functional scales were identified, including 13 clinician-rated scales, 7 self-reported scales, and 4 indices based on residential and vocational data. The Global Assessment of Functioning (GAF) and the Functional Assessment Short Test (FAST) were the most commonly used global and domain-specific scales, respectively. All other scales were used in ≤2 studies. Most studies used ≥1 domain-specific scale. The most common applications of functional scales in these studies were evaluations of the relationships between global or domain-specific psychosocial functioning and cognitive functioning (eg, executive function, attention, language, learning, memory) or clinical variables (eg, symptoms, duration of illness, number of hospitalizations, number of episodes). CONCLUSIONS: The results of this review show growing interest in the assessment of functioning in patients with BD, with an emphasis on specific domains such as work/educational, social, family, and cognitive functioning and high utilization of the GAF and FAST scales in published literature.


Asunto(s)
Trastorno Bipolar/psicología , Cognición , Adulto , Atención , Trastornos del Conocimiento/diagnóstico , Función Ejecutiva , Femenino , Humanos , Masculino , Memoria , Persona de Mediana Edad , Pruebas Neuropsicológicas , Evaluación de Resultado en la Atención de Salud , Adulto Joven
5.
Hum Mol Genet ; 25(11): 2324-2330, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-26936823

RESUMEN

Leukocyte telomere length (LTL), which reflects telomere length in other somatic tissues, is a complex genetic trait. Eleven SNPs have been shown in genome-wide association studies to be associated with LTL at a genome-wide level of significance within cohorts of European ancestry. It has been observed that LTL is longer in African Americans than in Europeans. The underlying reason for this difference is unknown. Here we show that LTL is significantly longer in sub-Saharan Africans than in both Europeans and African Americans. Based on the 11 LTL-associated alleles and genetic data in phase 3 of the 1000 Genomes Project, we show that the shifts in allele frequency within Europe and between Europe and Africa do not fit the pattern expected by neutral genetic drift. Our findings suggest that differences in LTL within Europeans and between Europeans and Africans is influenced by polygenic adaptation and that differences in LTL between Europeans and Africans might explain, in part, ethnic differences in risks for human diseases that have been linked to LTL.


Asunto(s)
Leucocitos/citología , Homeostasis del Telómero/genética , Acortamiento del Telómero/genética , Telómero/genética , Adolescente , Adulto , Negro o Afroamericano/genética , Anciano , Anciano de 80 o más Años , Alelos , Población Negra/genética , Niño , Femenino , Flujo Genético , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Población Blanca/genética
6.
Hum Mol Genet ; 25(12): 2612-2620, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27008869

RESUMEN

Endometrial cancer is the most common gynecological malignancy in the developed world. Although there is evidence of genetic predisposition to the disease, most of the genetic risk remains unexplained. We present the meta-analysis results of four genome-wide association studies (4907 cases and 11 945 controls total) in women of European ancestry. We describe one new locus reaching genome-wide significance (P < 5 × 10 -8) at 6p22.3 (rs1740828; P = 2.29 × 10 -8, OR = 1.20), providing evidence of an additional region of interest for genetic susceptibility to endometrial cancer.


Asunto(s)
Neoplasias Endometriales/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Cromosomas Humanos Par 6/genética , Neoplasias Endometriales/patología , Femenino , Genotipo , Humanos , Polimorfismo de Nucleótido Simple , Población Blanca/genética
7.
Brain Behav Immun ; 32: 159-63, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23602876

RESUMEN

Relatively short telomere length may serve as a marker of accelerated aging, and shorter telomeres have been linked to chronic stress. Specific lifestyle behaviors that can mitigate the effects of stress might be associated with longer telomere lengths. Previous research suggests a link between behaviors that focus on the well-being of others, such as volunteering and caregiving, and overall health and longevity. We examined relative telomere length in a group of individuals experienced in Loving-Kindness Meditation (LKM), a practice derived from the Buddhist tradition which utilizes a focus on unselfish kindness and warmth towards all people, and control participants who had done no meditation. Blood was collected by venipuncture, and Genomic DNA was extracted from peripheral blood leukocytes. Quantitative real time PCR was used to measure relative telomere length (RTL) (Cawthon, 2002) in fifteen LKM practitioners and 22 control participants. There were no significant differences in age, gender, race, education, or exposure to trauma, but the control group had a higher mean body mass index (BMI) and lower rates of past depression. The LKM practitioners had longer RTL than controls at the trend level (p=.083); among women, the LKM practitioners had significantly longer RTL than controls, (p=.007), which remained significant even after controlling for BMI and past depression. Although limited by small sample size, these results offer the intriguing possibility that LKM practice, especially in women, might alter RTL, a biomarker associated with longevity.


Asunto(s)
Amor , Meditación/psicología , Telómero/fisiología , Telómero/ultraestructura , Adulto , Índice de Masa Corporal , ADN/genética , ADN/ultraestructura , Interpretación Estadística de Datos , Femenino , Humanos , Leucocitos/ultraestructura , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
8.
NAR Cancer ; 5(3): zcad039, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37519629

RESUMEN

CCNE1 amplification is a common alteration in high-grade serous ovarian cancer and occurs in 15-20% of these tumors. These amplifications are mutually exclusive with homologous recombination deficiency, and, as they have intact homologous recombination, are intrinsically resistant to poly (ADP-ribose) polymerase inhibitors or chemotherapy agents. Understanding the molecular mechanisms that lead to this mutual exclusivity may reveal therapeutic vulnerabilities that could be leveraged in the clinic in this still underserved patient population. Here, we demonstrate that CCNE1-amplified high-grade serous ovarian cancer cells rely on homologous recombination to repair collapsed replication forks. Cyclin-dependent kinase 2, the canonical partner of cyclin E1, uniquely regulates homologous recombination in this genetic context, and as such cyclin-dependent kinase 2 inhibition synergizes with DNA damaging agents in vitro and in vivo. We demonstrate that combining a selective cyclin-dependent kinase 2 inhibitor with a DNA damaging agent could be a powerful tool in the clinic for high-grade serous ovarian cancer.

9.
Tumour Biol ; 32(2): 347-57, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21080252

RESUMEN

The neural cell adhesion molecule L1 has recently been shown to be expressed in pancreatic adenocarcinoma (PDAC) cells. In this report, we demonstrate that L1 is expressed by moderately- to poorly-differentiated PDAC cells in situ, and that L1 expression is a predictor of poor patient survival. In vitro, reduced reactivity of an anti-L1 carboxy-terminus-specific antibody was observed in the more poorly differentiated fast-growing (FG) variant of the COLO357 population, versus its well-differentiated slow-growing (SG) counterpart, even though they express equivalent total L1. The carboxy-terminus of L1 mediates binding to the MAP kinase-regulating protein RanBPM and mutation of T1247/S1248 within this region attenuates the expression of malignancy associated proteins and L1-induced tumorigenicity in mice. Therefore, we reasoned that the differential epitope exposure observed might be indicative of modifications responsible for regulating these events. However, epitope mapping demonstrated that the major determinant of binding was actually N1251; mutation of T1247 and S1248, alone or together, had little effect on C20 binding. Moreover, cluster assays using CD25 ectodomain/L1 cytoplasmic domain chimeras demonstrated the N1251-dependent, RanBPM-independent stimulation of erk phosphorylation in these cells. Reactivity of this antibody also reflects the differential exposure of extracellular epitopes in these COLO357 sublines, consistent with the previous demonstration of L1 ectodomain conformation modulation by intracellular modifications. These data further support a central role for L1 in PDAC, and define a specific role for carboxy-terminal residues including N1251 in the regulation of L1 activity in PDAC cells.


Asunto(s)
Adenocarcinoma/metabolismo , Biomarcadores de Tumor/metabolismo , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Neoplasias Pancreáticas/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Anticuerpos/inmunología , Antígenos CD20/inmunología , Antígenos CD20/metabolismo , Diferenciación Celular , Línea Celular Tumoral , Epítopos , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patología , Pronóstico
10.
Neuropsychiatr Dis Treat ; 17: 3215-3228, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34707359

RESUMEN

PURPOSE: To understand similarities and differences in patient treatment goals as selected by US psychiatrists, adult patients with schizophrenia, and their caregivers in a real-world setting in the United States, including stratification by current medication and age. PATIENTS AND METHODS: Data were drawn from the Adelphi Schizophrenia Disease Specific Programme™, a point-in-time survey of psychiatrists and their consulting adult patients with schizophrenia, conducted from June to October 2019. Psychiatrists completed record forms for their next 8 consecutive outpatients and (where possible) 2 inpatients matching inclusion criteria. Participating psychiatrists, patients, and caregivers completed treatment goal questionnaires as part of the survey. RESULTS: Psychiatrists (n = 124) provided data on 1204 patients with schizophrenia, including 1135 on drug treatment (207 inpatients [18%] and 928 outpatients [82%]); questionnaires were completed by 555 patients and 135 caregivers. Decrease in disease symptoms was identified as the most important patient treatment goal by patients (64%), psychiatrists (selecting for 63% of patients), and caregivers (selecting for 68% of patients). Patients, psychiatrists, and caregivers similarly rated the least important goals (less sexual problems and less weight gain). Patients indicated their current medication helped to reach their most important goals: decrease in disease symptoms (68%) and thinking more clearly (39%). Findings based on analysis of treatment goals by treatment and age were similar to overall trends. CONCLUSION: These findings, including identification of a primary consensus goal of decrease in disease symptoms, may help with discussions between patients with schizophrenia, psychiatrists, and caregivers to inform effective management strategies and encourage shared decision-making.

11.
Transl Med UniSa ; 24(1): 24-29, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36447745

RESUMEN

Telomere length (TL) is considered a biomarker of ageing although this topic is still debated. Also, sleep pattern changes are physiological part of the normal ageing process. In fact, it is widely recognized that sleep duration declines with age, leading to dysregulation of circadian rhythms. The aim of our study was to analyse the possible association of sleep duration with TL in a sample of 135 subjects with ages ranging from 20 to 111 years, recruited from Palermo and neighbouring municipalities in Sicily (Italy). Preliminary data suggest that relative TL (RTL) decreases with age in both men and women. However, at older ages, the difference between men and women tends to narrow. Nonagenarian and centenarian women do not show RTL values significantly different from those observed in adult and old women (40-89 years aged). Moreover, to analyse the relationship between TL and sleep, we stratified sleep duration into greater or lesser than 8-h periods. We found that centenarians, who daily sleep 8 hours or more, have longer RTL than centenarians who sleep fewer than 8 hours. Although the relatively small sample size of centenarians, we provide preliminary evidence that sleep duration may affect the RTL of centenarians. To the best of our knowledge, this is the first study to examine the relationship between centenarians, RTL and sleep duration. Further studies with greater sample size of centenarians are required to replicate and extend these data.

12.
J Cancer Epidemiol ; 2021: 8884364, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33986807

RESUMEN

OBJECTIVE: Endometrial cancers have historically been classified by histomorphologic appearance, which is subject to interobserver disagreement. As molecular and biomarker testing has become increasingly available, the prognostic significance and accuracy of histomorphologic diagnoses have been questioned. To address these issues for a large, prospective cohort study, we provide the results of a centralized pathology review and biomarker analysis of all incidental endometrial carcinomas occurring between 1976 and 2012 in the Nurses' Health Study. METHODS: Routine histology of all (n = 360) cases was reviewed for histomorphologic diagnosis. Cases were subsequently planted in a tissue microarray to explore expression of a variety of biomarkers (e.g., ER, PR, p53, PTEN, PAX2, AMACR, HNF1ß, Napsin A, p16, PAX8, and GATA3). RESULTS: Histologic subtypes included endometrioid (87.2%), serous (5.6%), carcinosarcoma (3.9%), clear cell (1.7%), and mixed type (1.7%). Biomarker results within histologic subtypes were consistent with existing literature: abnormal p53 was frequent in serous cases (74%), and HNF1ß (67%), Napsin A (67%), and AMACR (83%) expression was frequent in clear cell carcinomas. Our dataset also allowed for examination of biomarker expression across non-preselected histologies. The results demonstrated that (1) HNF1ß was not specific for clear cell carcinoma, (2) TP53 mutations occurred across many histologies, and (3) GATA3 was expressed across multiple histotypes, with 75% of positive cases demonstrating high-grade features. CONCLUSIONS: Our findings establish the subtypes of endometrial cancer occurring in the Nurses' Health Study, corroborate the sensitivity of certain well-established biomarkers, and call into question previously identified associations between certain biomarkers (e.g., HNF1B) and particular histotypes.

13.
Cytometry A ; 77(12): 1160-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20687200

RESUMEN

The morphology of dendrites and the axon determines how a neuron processes and transmits information. Neurite morphology is frequently analyzed by Sholl analysis or by counting the total number of neurites and branch tips. However, the time and resources required to perform such analysis by hand is prohibitive for the processing of large data sets and introduces problems with data auditing and reproducibility. Furthermore, analyses performed by hand or using course-grained morphometric data extraction tools can obscure subtle differences in data sets because they do not store the data in a form that facilitates the application of multiple analytical tools. To address these shortcomings, we have developed a program (titled "Bonfire") to facilitate digitization of neurite morphology and subsequent Sholl analysis. Our program builds upon other available open-source morphological analysis tools by performing Sholl analysis on subregions of the neuritic arbor, enabling the detection of local level changes in dendrite and axon branching behavior. To validate this new tool, we applied Bonfire analysis to images of hippocampal neurons treated with 25 ng/ml brain-derived neurotrophic factor (BDNF) and untreated control neurons. Consistent with prior findings, conventional Sholl analysis revealed that global exposure to BDNF increases the number of neuritic intersections proximal to the soma. Bonfire analysis additionally uncovers that BDNF treatment affects both root processes and terminal processes with no effect on intermediate neurites. Taken together, our data suggest that global exposure of hippocampal neurons to BDNF results in a reorganization of neuritic segments within their arbors, but not necessarily a change in their number or length. These findings were only made possible by the neurite-specific Sholl data returned by Bonfire analysis.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Neuritas/ultraestructura , Neuronas/ultraestructura , Reconocimiento de Normas Patrones Automatizadas/métodos , Animales , Factor Neurotrófico Derivado del Encéfalo/farmacología , Células Cultivadas , Hipocampo/citología , Hipocampo/efectos de los fármacos , Neuritas/efectos de los fármacos , Neuronas/efectos de los fármacos , Ratas
14.
PLoS One ; 15(6): e0234391, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32525914

RESUMEN

BACKGROUND: Pathological and clinical stage are associated with prostate cancer-specific survival after prostatectomy. With PSA screening, the post-surgery prognostic utility of clinical stage is debatable in studies seeking to identify new biomarkers. Few studies have investigated clinical stage and lethal prostate cancer association after accounting for pathological stage. We hypothesize that clinical stage provides prognostic information beyond pathological stage in the PSA era. METHODS: Cox regression models tested associations between clinical and pathological stage and lethal prostate cancer among 3,064 participants from the Health Professionals Follow-Up Study and Physicians' Health Study (HPFS/PHS) who underwent prostatectomy. Likelihood ratio tests and c-statistics were used to assess the models' prognostic utility. Equivalent analyses were performed in 16,134 men who underwent prostatectomy at Johns Hopkins. RESULTS: Independently, clinical and pathological stage were associated (p<0.0001 for both) with rate of lethal prostate cancer in HPFS/PHS. The model with clinical and pathological stage fit significantly better than the model with only pathological stage in all men (p = 0.01) and in men diagnosed during the PSA era (p = 0.04). The mutually adjusted model also improved discriminatory ability. In the Johns Hopkins cohort, the model with clinical and pathological stage improved discriminatory ability and fit significantly better overall (p<0.0001) and in the PSA era (p<0.0001). CONCLUSIONS: Despite stage migration resulting from widespread PSA screening, clinical stage remains associated with progression to lethal prostate cancer independent of pathological stage. Future studies evaluating associations between new factors and poor outcome following prostatectomy should consider including both clinical and pathological stages since the data is already available.


Asunto(s)
Calicreínas/sangre , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Prostatectomía , Neoplasias de la Próstata/cirugía , Estados Unidos
15.
Biochem Biophys Res Commun ; 389(2): 257-64, 2009 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-19720049

RESUMEN

Previously we identified threonine-1172 (T1172) in the cytoplasmic domain of the cell adhesion molecule L1 as phosphorylated in pancreatic cancer cells. Although both CKII- and PKC-blockade suppressed this modification, only CKII was capable of phosphorylating T1172 of a recombinant L1 cytoplasmic domain, suggesting the requirement for additional events to facilitate availability of T1172 to PKC. In this study, we demonstrate that the region around T1172 exists in distinct conformations based on both T1172 phosphorylation and the integrity of surrounding residues. We further demonstrate the role of membrane-proximal and membrane-distal residues in regulating cytoplasmic domain conformation, and that modification of 3 of the 4 tyrosines in the L1 cytoplasmic domain promote conformational changes that facilitate other events. In particular, phenylalanine-substitution of tyrosine-1151 or tyrosine-1229 promote opening up of the cytoplasmic domain in a manner that facilitates phosphorylation of the other 3 tyrosines, as well as phosphorylation of T1172 by PKCalpha. Importantly, we show that phosphorylation of serine-1181 is required for T1172 phosphorylation by CKII. These data define a specific role for secondary structure in regulating the availability of T1172 that facilitates phosphorylation by PKC.


Asunto(s)
Molécula L1 de Adhesión de Célula Nerviosa/química , Serina/química , Treonina/química , Tirosina/química , Secuencia de Aminoácidos , Anticuerpos Fosfo-Específicos/inmunología , Quinasa de la Caseína II/metabolismo , Citoplasma/metabolismo , Epítopos/inmunología , Humanos , Datos de Secuencia Molecular , Mutación , Molécula L1 de Adhesión de Célula Nerviosa/genética , Fosforilación , Pliegue de Proteína , Proteína Quinasa C-alfa/metabolismo , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Serina/genética , Tirosina/genética
16.
Cancer Res ; 67(9): 4364-72, 2007 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17483350

RESUMEN

The receptor tyrosine kinase ErbB-2 plays an important role in the regulation of growth factor-induced signal transduction cascades in the epithelium, and ErbB-2 is frequently overexpressed in epithelial tumors. Our previous studies on clinical prostate cancer specimens indicated that ErbB-2 expression was increased in patients undergoing hormone ablation therapy. We had also shown that the critical cell cycle regulatory gene cyclin D1 and its promoter were targets of proliferative signaling in prostate cancer cell lines, and that cyclin D1 was required for ErbB-2-induced mammary tumorigenesis. In the current studies, we found that increased ErbB-2 membrane expression correlated with increased nuclear cyclin D1 staining in clinical prostate cancer specimens, and that expression of ErbB-2 was capable of inducing cell cycle progression in human prostate cancer cell lines. We further showed that ErbB-2 induced the cyclin D1 promoter in DU145 cells, and that small interfering RNA knockdown of cyclin D1 protein levels blocked a significant proportion of the heregulin-induced cell cycle progression in LNCaP cells. Probasin promoter-targeted expression of an activated ErbB-2 isoform induced cyclin D1 expression in the mouse prostate, commensurate with prostate intraepithelial neoplasia. Together, these in vitro and in vivo studies identify cyclin D1 as a critical downstream target of ErbB-2 in the prostate epithelium, both of which are possible therapeutic targets for cancer intervention. Furthermore, our novel mouse model provides a useful platform for ongoing in vivo investigations of ErbB-2 signaling in the prostate epithelium.


Asunto(s)
Ciclina D1/biosíntesis , Regulación Neoplásica de la Expresión Génica , Genes bcl-1 , Neoplasia Intraepitelial Prostática/genética , Neoplasias de la Próstata/genética , Receptor ErbB-2/biosíntesis , Animales , Ciclo Celular/fisiología , Procesos de Crecimiento Celular/fisiología , Línea Celular Tumoral , Ciclina D1/genética , Células Epiteliales/patología , Humanos , Masculino , Ratones , Regiones Promotoras Genéticas , Neoplasia Intraepitelial Prostática/metabolismo , Neoplasia Intraepitelial Prostática/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , ARN Interferente Pequeño/genética
17.
Mol Biol Cell ; 16(11): 5103-14, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16120643

RESUMEN

Temporal and spatial assembly of signal transduction machinery determines dendrite branch patterning, a process crucial for proper synaptic transmission. Our laboratory previously cloned and characterized cypin, a protein that decreases PSD-95 family member localization and regulates dendrite number. Cypin contains zinc binding, collapsin response mediator protein (CRMP) homology, and PSD-95, Discs large, zona occludens-1 binding domains. Both the zinc binding and CRMP homology domains are needed for dendrite patterning. In addition, cypin binds tubulin via its CRMP homology domain to promote microtubule assembly. Using a yeast two-hybrid screen of a rat brain cDNA library with cypin lacking the carboxyl terminal eight amino acids as bait, we identified snapin as a cypin binding partner. Here, we show by affinity chromatography and coimmunoprecipitation that the carboxyl-terminal coiled-coil domain (H2) of snapin is required for cypin binding. In addition, snapin binds to cypin's CRMP homology domain, which is where tubulin binds. We also show that snapin competes with tubulin for binding to cypin, resulting in decreased microtubule assembly. Subsequently, overexpression of snapin in primary cultures of hippocampal neurons results in decreased primary dendrites present on these neurons and increased probability of branching. Together, our data suggest that snapin regulates dendrite number in developing neurons by modulating cypin-promoted microtubule assembly.


Asunto(s)
Tipificación del Cuerpo/fisiología , Proteínas Portadoras/metabolismo , Dendritas/fisiología , Guanina Desaminasa/metabolismo , Microtúbulos/fisiología , Proteínas de Transporte Vesicular/metabolismo , Animales , Unión Competitiva , Células COS , Técnicas de Cultivo de Célula , Chlorocebus aethiops , Cromatografía de Afinidad , Hipocampo/embriología , Microtúbulos/metabolismo , Modelos Biológicos , Neuronas/metabolismo , Estructura Terciaria de Proteína , Ratas , Sinaptosomas/metabolismo , Transfección
18.
Nat Neurosci ; 7(2): 145-52, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14730308

RESUMEN

Dendrite branching has an important role in normal brain function. Here we report that overexpression of cypin, a protein that has guanine deaminase activity and is expressed in developing processes in rat hippocampal neurons, results in increased dendrite branching in primary culture. Mutant cypin proteins that lack guanine deaminase activity act in a dominant-negative manner when expressed in primary neurons. Furthermore, we knocked down cypin protein levels using a new strategy: expressing a 5' end-mutated U1 small nuclear RNA (snRNA) to inhibit maturation of cypin mRNA. Neurons that express this mutant snRNA show little or no detectable cypin protein and fewer dendrites than normal. In addition, we found that cypin binds directly to tubulin heterodimers and promotes microtubule polymerization. Thus, our results demonstrate a new pathway by which dendrite patterning is regulated, and we also introduce a new method for decreasing endogenous protein expression in neurons.


Asunto(s)
Tipificación del Cuerpo/fisiología , Proteínas Portadoras/fisiología , Dendritas/fisiología , Guanina Desaminasa/fisiología , Hipocampo/embriología , Microtúbulos/fisiología , Animales , Células Cultivadas , Embrión de Mamíferos , Inmunohistoquímica , Mutación , ARN Nuclear Pequeño/genética , Ratas , Transfección
19.
Nat Commun ; 9(1): 3166, 2018 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-30093612

RESUMEN

Endometrial cancer is the most commonly diagnosed cancer of the female reproductive tract in developed countries. Through genome-wide association studies (GWAS), we have previously identified eight risk loci for endometrial cancer. Here, we present an expanded meta-analysis of 12,906 endometrial cancer cases and 108,979 controls (including new genotype data for 5624 cases) and identify nine novel genome-wide significant loci, including a locus on 12q24.12 previously identified by meta-GWAS of endometrial and colorectal cancer. At five loci, expression quantitative trait locus (eQTL) analyses identify candidate causal genes; risk alleles at two of these loci associate with decreased expression of genes, which encode negative regulators of oncogenic signal transduction proteins (SH2B3 (12q24.12) and NF1 (17q11.2)). In summary, this study has doubled the number of known endometrial cancer risk loci and revealed candidate causal genes for future study.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Endometriales/genética , Predisposición Genética a la Enfermedad , Alelos , Cromatina/química , Femenino , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Factores de Riesgo , Transducción de Señal
20.
Cancer Epidemiol Biomarkers Prev ; 26(5): 727-735, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28052940

RESUMEN

Background: Endometrial tumors arise from a hormonally responsive tissue. Defining subtypes by hormone receptor expression might better inform etiology and prediction of patient outcomes. We evaluated the potential role of tumor estrogen receptor (ER) and progesterone receptor (PR) expression to define endometrial cancer subtypes.Methods: We measured semi-continuous ER and PR protein expression in tissue specimens from 360 endometrial primary tumors from the Nurses' Health Study. To explore the impact of different definitions of marker positivity, we dichotomized ER and PR expression at different cut points in increments of 5% positive cells. Logistic regression was used to estimate associations between endometrial cancer risk factors, such as body mass index, with dichotomous ER or PR status. Reclassification statistics were used to assess whether adding dichotomous ER or PR status to standard prognostic factors of stage, grade, and histologic type would improve endometrial cancer-specific mortality prediction.Results: Compared with not being obese, obesity increased the odds of having an ER-positive tumor at cut points of 0% to 20% [maximum OR, 2.92; 95% confidence interval (CI), 1.34-6.33] as well as the odds of having a PR-positive tumor at cut points of 70% to 90% (maximum OR, 2.53; 95% CI, 1.36-4.68). Adding dichotomous tumor ER or PR status to the panel of standard predictors did not improve both model discrimination and calibration.Conclusions: Obesity may be associated with greater endometrial tumor expression of ER and PR. Adding either marker does not appear to improve mortality prediction beyond the standard predictors.Impact: Body mass index might explain some of the biological variation among endometrial tumors. Cancer Epidemiol Biomarkers Prev; 26(5); 727-35. ©2017 AACR.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias Endometriales , Obesidad/complicaciones , Receptores de Estrógenos/biosíntesis , Receptores de Progesterona/biosíntesis , Adulto , Índice de Masa Corporal , Estudios de Cohortes , Neoplasias Endometriales/complicaciones , Neoplasias Endometriales/metabolismo , Neoplasias Endometriales/mortalidad , Femenino , Humanos , Persona de Mediana Edad , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Factores de Riesgo
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