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1.
Front Genet ; 14: 1320185, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38152652

RESUMEN

Ovarian cancer is one of the female reproductive system tumors. Chemotherapy is used for advanced ovarian cancer patients; however, drug resistance is a pivotal cause of chemotherapeutic failure. Hence, it is critical to explore the molecular mechanisms of drug resistance of ovarian cancer cells and to ameliorate chemoresistance. Noncoding RNAs (ncRNAs) have been identified to critically participate in drug sensitivity in a variety of human cancers, including ovarian cancer. Among ncRNAs, circRNAs sponge miRNAs and prevent miRNAs from regulation of their target mRNAs. CircRNAs can interact with DNA or proteins to modulate gene expression. In this review, we briefly describe the biological functions of circRNAs in the development and progression of ovarian cancer. Moreover, we discuss the underneath regulatory molecular mechanisms of circRNAs on governing drug resistance in ovarian cancer. Furthermore, we mention the novel strategies to overcome drug resistance via targeting circRNAs in ovarian cancer. Due to that circRNAs play a key role in modulation of drug resistance in ovarian cancer, targeting circRNAs could be a novel approach for attenuation of chemoresistance in ovarian cancer.

2.
Cancer Control ; 30: 10732748231206929, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37924202

RESUMEN

PURPOSE: This study aims to determine the optimal cut-off value of Ki-67 to better predict the recurrence of early low-risk endometrial cancer (EC). METHODS: Seven hundred and forty-eight patients diagnosed with low-risk EC from West China Second Hospital of Sichuan University and the First Affiliated Hospital of Chongqing Medical University were retrospectively analyzed. The receiver operating characteristic curve (ROC) and Youden index were used to calculate the optimal cut-off value of Ki-67 expression. The clinicopathological indexes between two groups divided by cut-off value of Ki-67 were compared. The univariate and multivariate regression analyses were performed to investigate risk factors connected to the recurrence of early low-risk EC. The survival analysis was shown in Kaplan-Meier curve. RESULT: Thirty-three patients were detected with tumor recurrence after primary surgery (4.4%); 33% was the optimal cut-off value of the Ki-67 index. A high Ki-67 was significantly associated with age (P = .002), myometrial invasion (P < .001), and the expression of P53 (P = .007). The multivariate regression analysis verified that Ki67 ≥ 33% was an independent prognostic factor for predicting recurrence. The recurrence-free survival (RFS) and the overall survival (OS) in high Ki-67 group was significantly lower than that in low Ki-67 group (P < .001 and P = .029, respectively). The prognostic values of ER, PR, and P53 in combination with Ki-67 were superior to each single predictor. CONCLUSIONS: The optimal cut-off value of Ki-67 for predicting recurrence is 33%, which quantitatively defines the specific value of Ki-67 that causes high-risk recurrence in early low-risk EC.


Asunto(s)
Neoplasias Endometriales , Proteína p53 Supresora de Tumor , Humanos , Femenino , Antígeno Ki-67/metabolismo , Pronóstico , Estudios Retrospectivos , Recurrencia Local de Neoplasia
3.
Front Med (Lausanne) ; 10: 1195546, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37502363

RESUMEN

Introduction: Placenta accreta spectrum (PAS) may cause enormous and potentially life-threatening hemorrhage in the intrapartum and postpartum periods in emergency cesarean section. How to reduce the occurrence of emergency cesarean section in patients with severe PAS is the key to reducing the adverse outcomes of them. This study aimed to investigate the impact of emergency cesarean section on the perioperative outcomes of pregnant women with PAS and neonates, and also aimed to explore the risk factors of emergency cesarean section in pregnant women with PAS. Materials and methods: A retrospective investigation was conducted among 163 pregnant women with severe PAS. Of these, 72 were subjected to emergency cesarean sections. Data on the perioperative characteristics of the mothers and neonates were collected. Multivariable linear regression analysis was used to detect associations between maternal and perioperative characteristics and volume of intraoperative bleeding. Binary logical regression was used to analyze the association between maternal preoperative characteristics and emergency cesarean section. Linear regression analysis is used to analyze the relationship between gestational age and emergency cesarean section. Results: The risks of emergency cesarean section increase 98, 112, 124, and 62% when the pregnant women with PAS accompanied by GHD, ICP, more prior cesarean deliveries and more severe PAS type, respectively. Noteworthy, the risk of emergency cesarean section decreases 5% when pre-pregnancy BMI increases 1 kg/m2 (OR: 0.95; CI: 0.82, 0.98; p = 0.038). Moreover, there is no significant linear correlation between emergency cesarean section and gestational age. Conclusion: GHD, ICP, multiple prior cesarean deliveries and severe PAS type may all increase the risk of emergency cesarean section for pregnant women with PAS, while high pre-pregnancy BMI may be a protective factor due to less activity level. For pregnant women with severe PAS accompanied by these high risk factors, more adequate maternal and fetal monitoring should be carried out in the third trimester to reduce the risk of emergency cesarean section.

4.
J Clin Med ; 12(3)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36769874

RESUMEN

BACKGROUND: Combining traditional clinical parameters with neuroendocrine markers to construct a nomogram model to predict the postoperative recurrence of neuroendocrine carcinoma of cervix (NECC). METHODS: A total of 257 patients were included in this study. Univariate and multivariate Cox regression analyses were used to establish a nomogram model in the training cohorts, which was further validated in the validation cohorts. The calibration curve was used to conduct the internal and external verification of the model. RESULTS: Overall, 41 relapse cases were observed in the training (23 cases) and validation (18 cases) cohorts. The univariate analysis preliminarily showed that FIGO stage, stromal invasion, nerve invasion, lymph vascular space invasion, lymph node involvement, cervical-uterine junction invasion and CgA were correlated with NECC recurrence. The multivariate analysis further confirmed that FIGO stage (p = 0.023), stromal invasion (p = 0.002), lymph vascular space invasion (p = 0.039) and lymph node involvement (p = 0.00) were independent risk factors for NECC recurrence, which were ultimately included in the nomogram model. In addition, superior consistency indices were demonstrated in the training (0.863, 95% CI 0.784-0.942) and validation (0.884, 95% CI 0.758-1.010) cohorts. CONCLUSIONS: The established nomogram model combining traditional clinical parameters with neuroendocrine markers can reliably and accurately predict the recurrence risks in NECC patients.

5.
Sensors (Basel) ; 22(7)2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35408200

RESUMEN

Conventional experimental modal analysis uses excitation and response information to estimate the frequency response function. However, many engineering structures face excitation signals that are difficult to measure, so output-only modal estimation is an important issue. In this paper, singular spectrum analysis is employed to construct a Hankel matrix of appropriate dimensions based on the measured response data, and the observability of the system state space model is used to treat the Hankel matrix as three components containing system characteristics, excitation and noise. Singular value decomposition is used to factorize the data matrix and use the characteristics of the left and right singular matrices to reduce the dimension of the data matrix to improve calculation efficiency. Furthermore, the singular spectrum is employed to estimate the minimum order to reconstruct the Hankel matrix; then, the excitation and noise components can be removed, and the system observability matrix can be obtained. By appropriately a factorizing system observability matrix, we obtain the system matrix to estimate the modal parameters. In addition, the fictitious modes produced by increasing the order of the matrix can be eliminated through the stabilization diagram.

7.
Front Aging Neurosci ; 13: 766525, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34966267

RESUMEN

Background: The efficacy of virtual reality (VR)-based intervention for improving cognition in patients with the chronic stage of stroke is controversial. The aims of this meta-analysis were to evaluate the effect of VR-based training combined with traditional rehabilitation on cognition, motor function, mood, and activities of daily living (ADL) after chronic stroke. Methods: The search was performed in the Cochrane Library (CENTRAL), EBSCO, EMBASE, Medline (OVID), Web of Science databases, PubMed, CINAHL Ovid, and Scopus from inception to May 31, 2021. All included studies were randomized controlled trials (RCTs) examining VR-based intervention combined with traditional rehabilitation for chronic stroke. The main outcomes of this study were cognition, including overall cognition (combined with all cognitive measurement results), global cognition (measured by the Montreal Cognitive Assessment, MoCA, and/or Mini-Mental State Examination, MMSE), and attention/execution. The additional outcomes were motor function, mood, and ADL. Subgroup analyses were conducted to verify the potential factors for heterogeneity. Results: Six RCTs including 209 participants were included for systematic review, and five studies of 177 participants were included in meta-analyses. Main outcome analyses showed large and significant effect size (ES) of VR-based training on overall cognition (g = 0.642; 95% CI = 0.134-1.149; and P = 0.013) and attention/execution (g = 0.695; 95% CI = 0.052-1.339; and P = 0.034). Non-significant result was found for VR-based intervention on global cognition (g = 0.553; 95% CI = -0.273-1.379; and P = 0.189). Additional outcome analyses showed no superiority of VR-based intervention over traditional rehabilitation on motor function and ADL. The ES of VR-based intervention on mood (g = 1.421; 95% CI = 0.448-2.393; and P = 0.004) was large and significant. In the subgroup analysis, large effects for higher daily intensity, higher weekly frequency, or greater dose of VR intervention were found. Conclusion: Our findings indicate that VR-based intervention combined with traditional rehabilitation showed better outcomes for overall cognition, attention/execution, and depressive mood in individuals with chronic stroke. However, VR-based training combined with traditional rehabilitation showed a non-significant effect for global cognition, motor function, and ADL in individuals with chronic stroke.

8.
Proc Natl Acad Sci U S A ; 117(46): 28763-28774, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33139573

RESUMEN

The molecular mechanisms by which receptor tyrosine kinases (RTKs) and heterotrimeric G proteins, two major signaling hubs in eukaryotes, independently relay signals across the plasma membrane have been extensively characterized. How these hubs cross-talk has been a long-standing question, but answers remain elusive. Using linear ion-trap mass spectrometry in combination with biochemical, cellular, and computational approaches, we unravel a mechanism of activation of heterotrimeric G proteins by RTKs and chart the key steps that mediate such activation. Upon growth factor stimulation, the guanine-nucleotide exchange modulator dissociates Gαi•ßγ trimers, scaffolds monomeric Gαi with RTKs, and facilitates the phosphorylation on two tyrosines located within the interdomain cleft of Gαi. Phosphorylation triggers the activation of Gαi and inhibits second messengers (cAMP). Tumor-associated mutants reveal how constitutive activation of this pathway impacts cell's decision to "go" vs. "grow." These insights define a tyrosine-based G protein signaling paradigm and reveal its importance in eukaryotes.


Asunto(s)
Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Proteínas de Unión al GTP Heterotriméricas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Células COS , Chlorocebus aethiops , Receptores ErbB/metabolismo , Células HEK293 , Células HeLa , Proteínas de Unión al GTP Heterotriméricas/fisiología , Humanos , Fosforilación , Proteínas Tirosina Quinasas Receptoras/fisiología , Transducción de Señal , Tirosina/metabolismo
9.
Int J Med Sci ; 14(13): 1410-1417, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29200955

RESUMEN

The present study evaluated the prognostic value of the epidermal growth factor receptor (EGFR) mutation status, and excision repair cross-complementation group 1 (ERCC1) and thymidylate synthase (TS) expression following intercalated tyrosine kinase inhibitor (TKI) therapy and platinum- and pemetrexed-based chemotherapies (subsequent second-line treatment) for patients with adenocarcinoma non-small-cell lung cancer (AC-NSCLC). In total, 131 patients with AC-NSCLC were enrolled. The EGFR mutation status and ERCC1 and TS expression were evaluated through direct DNA sequencing and immunohistochemical analyses, respectively. The EGFR mutation status and ERCC1 and TS expression were the significant predictors of clinical outcomes. The EGFR mutation status was the main outcome predictor for overall survival (OS) benefits in the overall population. Further exploratory ERCC1 and TS expression analyses were conducted to provide additional insights. Low TS expression was predictive of improved OS of patients with negative EGFR-mutated advanced AC-NSCLC, whereas high ERCC1 expression resulted in poor OS in patients with positive EGFR-mutated advanced AC-NSCLC. TS and ERCC1 expression levels were effective prognostic factors for negative and positive EGFR-mutated AC-NSCLC, respectively. In conclusion, the present results indicate that the EGFR mutation status and TS and ERCC1 expression can be used as the predictors of OS after subsequent second-line treatments for AC-NSCLC.


Asunto(s)
Adenocarcinoma/genética , Proteínas de Unión al ADN/genética , Endonucleasas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Timidilato Sintasa/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma del Pulmón , Anciano , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mutación , Pronóstico
10.
Int J Med Sci ; 14(8): 785-790, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28824314

RESUMEN

Hypoxia is an important factor in tumor angiogenesis, metastasis, and resistance to chemotherapy or radiotherapy, and may be an indicator of poor prognosis. The transcription factor hypoxia-inducible factor 1 (HIF-1) is the key regulator of the hypoxic state. This study was designed to evaluate the prognostic value of HIF-1α expression in small cell lung cancer (SCLC). Forty-three paraffin-embedded biopsy materials were examined using immunohistochemistry. Our results indicated that the expression of HIF-1α was high in males, and patients with poor Eastern Cooperative Oncology Group (ECOG) performance status and metastases. To elucidate the prognostic value of HIF-1α expression, Kaplan-Meier analysis was carried out and the results showed that patients with high HIF-1α expression had a poorer prognosis than patients with low expression of HIF-1α. After adjusting clinical parameters by the Cox proportional hazards model, our results demonstrated that high HIF-1α expression is an independent prognostic factor for SCLC with a 39.2-fold risk of death (p<0.003). In conclusion, we have provided evidence that HIF-1α expression has significant value in predicting survival of patients with SCLC and is an independent prognostic factor beyond ECOG performance and metastasis status.


Asunto(s)
Biomarcadores de Tumor/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Neovascularización Patológica/genética , Carcinoma Pulmonar de Células Pequeñas/genética , Anciano , Anciano de 80 o más Años , Resistencia a Antineoplásicos/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neovascularización Patológica/diagnóstico , Neovascularización Patológica/patología , Pronóstico , Modelos de Riesgos Proporcionales , Carcinoma Pulmonar de Células Pequeñas/mortalidad , Carcinoma Pulmonar de Células Pequeñas/patología
11.
J Ultrasound Med ; 34(11): 2043-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26432825

RESUMEN

OBJECTIVES: Evidence reveals a pathophysiologic link between sleep apnea syndrome and cerebrovascular diseases. It is known that obstructive sleep apnea (OSA) may cause serial hemodynamic changes and structural abnormalities in the cerebral and cardiac arterial systems, but its effect on the cerebral venous system has remained unclear. The purpose of this study was to compare internal jugular vein hemodynamics between patients with OSA and healthy individuals. METHODS: Patients with OSA and age-, body mass index-, and sex-matched healthy control participants were recruited for a jugular venous duplex study and neurologic examination. The luminal area of the internal jugular vein, jugular venous flow volume, time-averaged mean velocity, and presence of jugular venous reflux were recorded. These flow characteristics were obtained at different respiratory statuses, and we analyzed the differences between patients and controls. RESULTS: In the OSA group, there was an increasing flow volume in total internal jugular veins at rest. The frequency of venous reflux in patients compared with controls was significantly decreased (26.7% versus 53.3%, respectively; P < .05). The internal jugular vein drainage dominance was greater on the left side in the OSA group (right versus left: 48.8% versus 51.2%), whereas it was greater on the right side in the control group (right versus left: 61.7% versus 38.3%). CONCLUSIONS: Our data showed peculiar internal jugular vein hemodynamics at baseline and different respiratory statuses in patients with OSA. These characteristics imply that cerebral venous drainage conditions might be involved in the pathophysiologic mechanisms of OSA syndrome.


Asunto(s)
Velocidad del Flujo Sanguíneo , Venas Cerebrales/fisiopatología , Circulación Cerebrovascular , Venas Yugulares/fisiopatología , Apnea Obstructiva del Sueño/fisiopatología , Venas Cerebrales/diagnóstico por imagen , Enfermedad Crónica , Femenino , Humanos , Venas Yugulares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Apnea Obstructiva del Sueño/diagnóstico por imagen , Ultrasonografía Doppler Dúplex/métodos
12.
Mol Biol Cell ; 25(22): 3654-71, 2014 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-25187647

RESUMEN

A long-standing issue in the field of signal transduction is to understand the cross-talk between receptor tyrosine kinases (RTKs) and heterotrimeric G proteins, two major and distinct signaling hubs that control eukaryotic cell behavior. Although stimulation of many RTKs leads to activation of trimeric G proteins, the molecular mechanisms behind this phenomenon remain elusive. We discovered a unifying mechanism that allows GIV/Girdin, a bona fide metastasis-related protein and a guanine-nucleotide exchange factor (GEF) for Gαi, to serve as a direct platform for multiple RTKs to activate Gαi proteins. Using a combination of homology modeling, protein-protein interaction, and kinase assays, we demonstrate that a stretch of ∼110 amino acids within GIV C-terminus displays structural plasticity that allows folding into a SH2-like domain in the presence of phosphotyrosine ligands. Using protein-protein interaction assays, we demonstrated that both SH2 and GEF domains of GIV are required for the formation of a ligand-activated ternary complex between GIV, Gαi, and growth factor receptors and for activation of Gαi after growth factor stimulation. Expression of a SH2-deficient GIV mutant (Arg 1745→Leu) that cannot bind RTKs impaired all previously demonstrated functions of GIV-Akt enhancement, actin remodeling, and cell migration. The mechanistic and structural insights gained here shed light on the long-standing questions surrounding RTK/G protein cross-talk, set a novel paradigm, and characterize a unique pharmacological target for uncoupling GIV-dependent signaling downstream of multiple oncogenic RTKs.


Asunto(s)
Receptores ErbB/química , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/química , Proteínas de Microfilamentos/química , Proteínas de Transporte Vesicular/química , Secuencia de Aminoácidos , Animales , Movimiento Celular , Receptores ErbB/genética , Receptores ErbB/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/genética , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Regulación de la Expresión Génica , Células HeLa , Humanos , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Pliegue de Proteína , Dominios y Motivos de Interacción de Proteínas , Transducción de Señal , Homología Estructural de Proteína , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
13.
Tumour Biol ; 35(5): 4719-25, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24453031

RESUMEN

The cytochrome P450 1B1 (CYP1B1) gene plays a key role in the metabolism of various carcinogens. The CYP1B1 Leu432Val polymorphism leads to leucine to valine substitution at codon 432. A lot of studies have shown that the CYP1B1 Leu432Val polymorphism was associated with urinary system cancers, especially prostate cancer. However, the results were still inconclusive. In this meta-analysis, by searching online databases and references of related reviews, we identified 17 eligible studies to assess the relationship between CYP1B1 Leu432Val polymorphism and urinary system cancers, including 7,783 cancer cases and 7,238 controls. By pooling all eligible studies, we found that the CYP1B1 Leu432Val polymorphism was not associated with overall urinary system cancers. However, in subgroup analyses, we found that the variant 432Val allele significantly increased the risk of prostate cancer (Val vs. Leu, odds ratio (OR) = 1.064, 95% confidence interval (CI) 0.981-1.154; Pheterogeneity = 0.002), while no association was found for bladder cancer (Val vs. Leu, OR = 0.942, 95% CI 0.853-1.041; Pheterogeneity = 0.504). No evidence of publication bias was found (Begg's test, P = 0.053; Egger's test, P = 0.073). In conclusion, based on 17 eligible studies, we found that the CYP1B1 Leu432Val polymorphism was associated with an increased risk of prostate cancer, while no association of bladder cancer was observed.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/genética , Predisposición Genética a la Enfermedad , Polimorfismo Genético , Neoplasias de la Próstata/genética , Neoplasias de la Vejiga Urinaria/genética , Citocromo P-450 CYP1B1 , Humanos , Masculino , Riesgo
14.
Cancers (Basel) ; 5(3): 959-84, 2013 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-24202329

RESUMEN

We report here that the Jun dimerization protein 2 (JDP2) plays a critical role as a cofactor for the transcription factors nuclear factor-erythroid 2-related factor 2 (Nrf2) and MafK in the regulation of the antioxidants and production of reactive oxygen species (ROS). JDP2 associates with Nrf2 and MafK (Nrf2-MafK) to increase the transcription of antioxidant response element-dependent genes. Oxidative-stress-inducing reagent led to an increase in the intracellular accumulation of ROS and cell proliferation in Jdp2 knock-out mouse embryonic fibroblasts. In Jdp2-Cre mice mated with reporter mice, the expression of JDP2 was restricted to granule cells in the brain cerebellum. The induced pluripotent stem cells (iPSC)-like cells were generated from DAOY medulloblastoma cell by introduction of JDP2, and the defined factor OCT4. iPSC-like cells expressed stem cell-like characteristics including alkaline phosphatase activity and some stem cell markers. However, such iPSC-like cells also proliferated rapidly, became neoplastic, and potentiated cell malignancy at a later stage in SCID mice. This study suggests that medulloblastoma cells can be reprogrammed successfully by JDP2 and OCT4 to become iPSC-like cells. These cells will be helpful for studying the generation of cancer stem cells and ROS homeostasis.

15.
Curr Opin Genet Dev ; 23(5): 519-25, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23932127

RESUMEN

Direct reprogramming of one cell type into another provides unprecedented opportunities to study fundamental biology, model disease, and develop regenerative medicine. Different paradigms of reprogramming strategies with different sets of factors have been developed to generate various cell types, including induced pluripotent stem cells, neuronal or neural precursor cells, cardiomyocyte-like cells, endothelial cells, and hepatocyte-like cells. Various exogenous factors, especially small molecules modulating signaling, cellular state, and transcription, have been identified to enhance and enable reprogramming. With an increased understanding of reprogramming mechanisms and discovery of new molecules, it is conceivable that reprogramming can be achieved in a more directed and deterministic manner under entirely chemically defined conditions.


Asunto(s)
Reprogramación Celular/genética , Células Madre Embrionarias/citología , Células Madre Pluripotentes Inducidas/citología , Células-Madre Neurales/citología , Diferenciación Celular/genética , Linaje de la Célula , Humanos , Miocitos Cardíacos/citología , Transducción de Señal , Factores de Transcripción/metabolismo , Transcripción Genética
16.
Mol Divers ; 16(2): 215-29, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22161217

RESUMEN

This study describes the synthesis and anti-inflammatory effects of furo[3', 2':3,4]naphtho[1,2-d] imidazole derivatives. Among these furo[3', 2':3,4]naphtho[1,2-d]imidazole derivatives, 2-(4-methoxyphenyl)furo [3', 2':3,4]naphtho[1,2-d]imidazole (12) exhibited a strong inhibitory activity against LPS-induced PGE(2) production, with an IC(50) value of 47 nM. Compound 12 is then further examined for its inhibitory effects in the protein expression of COX-2 and microsomal prostaglandin E(2) synthase-1 (mPGES-1) in Raw 264.7 cells. Our results indicate that compound 12 was capable against inhibiting LPS-induced mPGES-1 protein expression at a concentration of 1.0 µM and no inhibitory effect in COX-2 expression. The sepsis-induced PGE(2) production in rat serum decreased ~250% by the pretreatment of 12 at 10 mg/kg. These results are especially important since compound 12 exhibited good oral bioavailability (72%) and was not cytotoxic at a concentration of 10.0 µM. Therefore, compound 12 is a highly selective mPGES-1 inhibitor that can serve as a lead for the development of novel oral anti-inflammatory drug candidates.


Asunto(s)
Antiinflamatorios/farmacología , Inhibidores Enzimáticos/farmacología , Imidazoles/farmacología , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Administración Oral , Animales , Antiinflamatorios/síntesis química , Antiinflamatorios/toxicidad , Degranulación de la Célula/efectos de los fármacos , Línea Celular , Dinoprostona/metabolismo , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/toxicidad , Imidazoles/síntesis química , Imidazoles/toxicidad , Lipopolisacáridos/farmacología , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Neutrófilos/efectos de los fármacos , Neutrófilos/fisiología , Óxido Nítrico/metabolismo , Prostaglandina-E Sintasas , Relación Estructura-Actividad Cuantitativa , Ratas , Ratas Sprague-Dawley , Sepsis/metabolismo , Sepsis/patología , Superóxidos/metabolismo
17.
Sci Signal ; 4(192): ra64, 2011 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-21954290

RESUMEN

GIV (Gα-interacting vesicle-associated protein; also known as Girdin) enhances Akt activation downstream of multiple growth factor- and G protein (heterotrimeric guanosine 5'-triphosphate-binding protein)-coupled receptors to trigger cell migration and cancer invasion. We demonstrate that GIV is a tyrosine phosphoprotein that directly binds to and activates phosphoinositide 3-kinase (PI3K). Upon ligand stimulation of various receptors, GIV was phosphorylated at tyrosine-1764 and tyrosine-1798 by both receptor and non-receptor tyrosine kinases. These phosphorylation events enabled direct binding of GIV to the amino- and carboxyl-terminal Src homology 2 domains of p85α, a regulatory subunit of PI3K; stabilized receptor association with PI3K; and enhanced PI3K activity at the plasma membrane to trigger cell migration. Tyrosine phosphorylation of GIV and its association with p85α increased during metastatic progression of a breast carcinoma. These results suggest a mechanism by which multiple receptors activate PI3K through tyrosine phosphorylation of GIV, thereby making the GIV-PI3K interaction a potential therapeutic target within the PI3K-Akt pathway.


Asunto(s)
Movimiento Celular/fisiología , Activación Enzimática/fisiología , Proteínas de Microfilamentos/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Tirosina/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Análisis de Varianza , Línea Celular Tumoral , Cromatografía Liquida , Técnica del Anticuerpo Fluorescente , Humanos , Inmunoprecipitación , Modelos Moleculares , Fosforilación , Espectrometría de Masas en Tándem
18.
J Microbiol Immunol Infect ; 44(2): 139-43, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21439517

RESUMEN

BACKGROUND: Allergic rhinitis (AR) often coexists with and can significantly worsen bronchial asthma (BA). We evaluated the proportion of patients with BA and concomitant AR (BA+AR) diagnosed and treated in an average clinical practice. METHODS: A cross-sectional study methodology was used to determine the prevalence of AR in patients more than 15 years of age with a documented history of asthma who experienced wheezing during the prior 12 months. The International Study of Asthma and Allergies in Childhood standardized written questionnaire was used and therapeutic class choices were recorded. RESULTS: Among 750 surveyed asthma patients, 524 patients (69.9%) experienced AR. Of those with BA and AR, there were 44 patients (8.4%) who were not diagnosed with AR, and the treatment rate for AR was 62.1%. The most frequent severity level of BA and AR were moderate persistent (38.9%) and intermittent mild (52.5%), respectively. There were no significant differences between patients with AR and without AR. CONCLUSIONS: The prevalence of AR in patients with asthma was 69.9% in this study. Despite Allergic Rhinitis and its Impact on Asthma guideline recommendations encouraging evaluation and treatment of AR among asthmatics, nearly 8.4% of asthmatics with AR were undiagnosed, and 37.9% of asthmatics with AR were untreated for AR.


Asunto(s)
Asma/epidemiología , Rinitis Alérgica Perenne/epidemiología , Rinitis Alérgica Estacional/epidemiología , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Hipersensibilidad , Masculino , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios , Taiwán/epidemiología
19.
Cell Reprogram ; 12(3): 237-47, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20698766

RESUMEN

Induced pluripotent stem (iPS) cells have been generated from human somatic cells by ectopic expression of defined transcription factors. Application of this approach in human cells may have enormous potential to generate patient-specific pluripotent stem cells. However, traditional methods of reprogramming in human somatic cells involve the use of oncogenes c-MYC and KLF4, which are not applicable to clinical translation. In the present study, we investigated whether human fetal gut mesentery-derived cells (hGMDCs) could be successfully reprogrammed into induced pluripotent stem (iPS) cells by OCT4, SOX2, and NANOG alone. We used lentiviruses to express OCT4, SOX2, NANOG, in hGMDCs, then generated iPS cells that were identified by morphology, presence of pluripotency markers, global gene expression profile, DNA methylation status, capacity to form embryoid bodies (EBs), and terotoma formation. iPS cells resulting from hGMDCs were similar to human embryonic stem (ES) cells in morphology, proliferation, surface markers, gene expression, and epigenetic status of pluripotent cell-specific genes. Furthermore, these cells were able to differentiate into cell types of all three germ layers both in vitro and in vivo, as shown by EB and teratoma formation assays. DNA fingerprinting showed that the human iPS cells were derived from the donor cells, and are not a result of contamination. Our results provide proof that hGMDCs can be reprogrammed into pluripotent cells by ectopic expression of three factors (OCT4, SOX2, and NANOG) without the use of oncogenes c-MYC and KLF4.


Asunto(s)
Proteínas de Homeodominio/genética , Mesenterio/citología , Factor 3 de Transcripción de Unión a Octámeros/genética , Células Madre Pluripotentes/citología , Factores de Transcripción SOXB1/genética , Animales , Diferenciación Celular , Línea Celular , Citometría de Flujo , Humanos , Cariotipificación , Factor 4 Similar a Kruppel , Ratones , Ratones SCID , Proteína Homeótica Nanog , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Bioorg Med Chem ; 17(18): 6773-9, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19699097

RESUMEN

Synthesis and anti-inflammatory effects of certain furo[3',2':3,4]naphtho[1,2-d]imidazole derivatives 12-18 were studied. These compounds were synthesized from naphtho[1,2-b]furan-4,5-dione (10) which in turn was prepared from the known 2-hydroxy-1,4-naphthoquinone (7) in a one pot reaction. Furo[3',2':3,4]naphtho[1,2-d]imidazole (12) was inactive (IC(50) value of >30 microM) while its 5-phenyl derivative 13, with an IC(50) value of 16.3 and 11.4 microM against lysozyme and beta-glucuronidase release, respectively, was comparable to the positive trifluoperazine. The same potency was observed for 5-furan derivative 16 with an IC(50) value of 19.5 and 11.3 microM against lysozyme and beta-glucuronidase release, respectively. An electron-withdrawing NO(2) substituted on 5-phenyl or 5-furanyl group led to the devoid of activity as in the cases of 14 and 17. Among them, compound 15 exhibited significant inhibitory effects, with an IC(50) value of 7.4 and 5.0 microM against lysozyme and beta-glucuronidase release, respectively. For the LPS-induced NO production, the phenyl derivatives 12-15 were inactive while the nitrofuran counterparts 17 and 18 suppress LPS-induced NO production significantly, with an IC(50) value of 1.5 and 1.3 microM, respectively, which are more active than that of the positive 1400 W. Compounds 16-18 were capable of inhibiting LPS-induced iNOS protein expression at a dose-dependent manner in which compound 18, with an IC(50) of 0.52 microM in the inhibition of iNOS expression, is approximately fivefold more potent than that of the positive 1400 W. In the CLP rat animal model, compound 18 was found to be more active than the positive hydrocortisone in the inhibition of the iNOS mRNA expression in rat lung tissue. The sepsis-induced PGE2 production in rat serum decreased 150% by the pretreatment of 18 in a dose of 10 mg/kg.


Asunto(s)
Antiinflamatorios/química , Antiinflamatorios/farmacología , Imidazoles/química , Imidazoles/farmacología , Sepsis/tratamiento farmacológico , Animales , Antiinflamatorios/uso terapéutico , Línea Celular , Furanos/química , Expresión Génica/efectos de los fármacos , Imidazoles/uso terapéutico , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Prostaglandinas E/antagonistas & inhibidores , Prostaglandinas E/metabolismo , Ratas , Ratas Sprague-Dawley , Superóxidos/metabolismo
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