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1.
J Ethnopharmacol ; 329: 118081, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38570148

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Liujunzi formula has been used to treat liver cancer in China for many years, but its underlying mechanism remains unclear. We previously found that decreased expression of miR-122-3p was associated with liver cancer. In this study, we aimed to explore the target of miR-122-3p and the effect of the Liujunzi formula on miR-122-3p and its downstream events in liver cancer. MATERIAL AND METHODS: Bioinformatics pinpointed potential targets of miR-122-3p. The actual target was confirmed by miRNA mimic/inhibitor transfections and a dual-luciferase reporter assay. RNA-seq looked at downstream genes impacted by this target. Flow cytometry checked for changes in T cell apoptosis levels after exposing them to liver cancer cells. Gene expression was measured by RT-qPCR, western blotting, and immunofluorescence staining. RESULTS: Cell experiments found the Liujunzi extract (LJZ) upregulated miR-122-3p and in a dose-dependent manner. Bioinformatics analysis found UBE2I was a potential target of miR-122-3p, which was validated through experiments using miRNA mimics/inhibitors and a dual-luciferase reporter assay. RNA-seq data implicated the NF-κB pathway as being downstream of the miR-122-3p/UBE2I axis, further confirmed by forcing overexpression of UBE2I. Bioinformatic evidence suggested a link between UBE2I and T cell infiltration in liver cancer. Given that the NF-κB pathway drives PD-L1 expression, which can inhibit T cell infiltration, we investigated whether PD-L1 is a downstream effector of miR-122-3p/UBE2I. This was corroborated through mining public databases, UBE2I overexpression studies, and tumor-T cell co-culture assays. In addition, we also confirmed that LJZ downregulates UBE2I and NF-κB/PD-L1 pathways through miR-122-3p. LJZ also suppressed SUMOylation in liver cancer cells and protected PD-1+ T cells from apoptosis induced by co-culture with tumor cells. Strikingly, a miR-122-3p inhibitor abrogated LJZ's effects on UBE2I and PD-L1, and UBE2I overexpression rescued the LJZ-mediated effects on NF-κB and PD-L1. CONCLUSIONS: miR-122-3p targets UBE2I, thereby suppressing the NF-κB signaling cascade and downregulating PD-L1 expression, which potentiates anti-tumor immune responses. LJZ bolsters anti-tumor immunity by modulating the miR-122-3p/UBE2I/NF-κB/PD-L1 axis in liver cancer cells.


Assuntos
Medicamentos de Ervas Chinesas , Neoplasias Hepáticas , MicroRNAs , Enzimas de Conjugação de Ubiquitina , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Humanos , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Apoptose/efeitos dos fármacos , NF-kappa B/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células Hep G2 , Tolerância Imunológica/efeitos dos fármacos
2.
IEEE Trans Biomed Eng ; 69(2): 955-962, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34495826

RESUMO

OBJECTIVE: Electrical impedance tomography (EIT) is a noninvasive imaging technology used to reconstruct the conductivity distribution in objects and the human body. METHODS: In recent years, numerous EIT systems and image reconstruction algorithms have been developed. However, most of these EIT systems require conventional electrodes with conductive gels (wet electrodes) and cannot be adapted to different body types, resulting in limited applicability. RESULTS: In this study, a wearable wireless EIT belt with dry electrodes was designed to enable EIT imaging of the human body without using wet electrodes. The specific design of the belt mechanism and dry electrodes provide the advantages of easy wear and adaptation to different body sizes. Additionally, the Gauss-Newton method was used to optimize the EIT image. CONCLUSION: Finally, experiments were performed on the phantom and human body to validate the performance of the proposed EIT belt. SIGNIFICANCE: The results demonstrate that the proposed system can provide accurate location information of the objects in the EIT image and the system can be successfully applied for noninvasive measurement of the human body.


Assuntos
Tomografia , Dispositivos Eletrônicos Vestíveis , Impedância Elétrica , Eletrodos , Humanos , Tomografia/métodos , Tomografia Computadorizada por Raios X
3.
Carbohydr Polym ; 242: 116462, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32564825

RESUMO

Alginate oligosaccharide (AOS) is a biological carbohydrate formed from the degradation of sodium alginate. AOS used in this study was enzymatically prepared and had varying degrees of polymerization (2-8). AOS applied to harvested kiwifruit stored at 25 °C inhibited gray mold, blue mold, and black rot. AOS inhibited pectin solubilization, gene expression of pectin methylesterase and polygalacturonase, and the corresponding enzyme activity of their encoded proteins in kiwifruit. In contrast, AOS induced antioxidant gene expression and enzyme activity, including catalase and superoxide dismutase. The level of total phenols and flavonoids in kiwifruit was also elevated. AOS treatment also had a beneficial effect on fruit quality. Collectively, the results indicate that postharvest treatment with AOS inhibits postharvest decay and prolongs fruit quality by suppressing cell wall degradation and eliciting antioxidants in harvested kiwifruit. AOS has the potential to be used to preserve and extend the postharvest quality of kiwifruit.


Assuntos
Actinidia/efeitos dos fármacos , Alginatos/farmacologia , Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Conservação de Alimentos , Oligossacarídeos/farmacologia , Actinidia/metabolismo , Alginatos/química , Alginatos/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Frutas/efeitos dos fármacos , Frutas/metabolismo , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Poligalacturonase/antagonistas & inibidores , Poligalacturonase/genética , Poligalacturonase/metabolismo
4.
Cogn Emot ; 34(6): 1097-1111, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32026747

RESUMO

It is well established that gratitude favours prosocial tendencies in neutral and amicable social interactions. Less is clear, however, about the role of gratitude in threatening situations that breed competitive impulses. As gratitude inhibits self-centred impulses and motivates a communal orientation, we predict and demonstrate that gratitude reduces competitive behaviour in threatening interactions. In Study 1 (N = 171), after emotion induction, participants went through the classic Trucking game paradigm, whereby a bogus opponent behaved in a competitive manner (i.e. closing the gate on them). Gratitude, as compared to joy and a neutral mood state, reduced participants' competitive behaviour against the opponent. In Study 2 (N = 422), after losing to a bogus opponent on a self-relevant task, participants were given an opportunity to sabotage the opponent's chances of winning a lottery. Individuals induced to feel gratitude showed less sabotaging behaviour than those in a neutral mood state. Importantly, this effect was only observed against a highly competitive, but not a neutral, opponent, suggesting that gratitude inhibits competitive behaviour only under high threat. Our findings suggest that gratitude is instrumental in arresting the competitive cycles from developing in threatening social interactions.


Assuntos
Comportamento Competitivo , Emoções , Interação Social , Feminino , Humanos , Masculino , Adulto Jovem
5.
Microb Pathog ; 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30096430

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

6.
Cleft Palate Craniofac J ; 55(6): 807-813, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28001101

RESUMO

BACKGROUND: Humanitarian surgical organizations provide palatoplasties for patients without access to surgical care. Few organizations have evaluated the outcomes of these trips. This study evaluates the palatal fistula rate in patients from two cohorts in rural China and one in the United States. METHODS: This study compared the odds of fistula formation among three cohorts whose palates were repaired between 2005 and 2009. One cohort included 97 Chinese patients operated on by teams from the United States and Canada under the auspices of Resurge International. They were compared to cohorts at Huaxi Stomatology Hospital and the University of California San Francisco (UCSF). Age, fistula presence, and Veau class were compared among cohorts using Chi-square tests. Logistic regression was used to analyze predictors of fistula formation. RESULTS: The fistula risk was 35.4% in patients treated by humanitarian teams, 12.8% at Huaxi University Hospital and 2.5% at UCSF ( P < 0.001). Age and Veau class were associated with fistula formation (Age P = 0.0015; Veau P < 0.001). ReSurge and Huaxi patients had 20.2 and 5.6 times the odds of developing a fistula, respectively, compared to UCSF patients ( P < 0.01, both). A multivariable model controlling for surgical group, age, and gender showed an association between Veau class and the odds of fistula formation. CONCLUSIONS: Chinese children undergoing palatoplasty by international teams had higher odds of palatal fistula than children treated by Chinese surgeons in established institutions and children treated in the United States. More research is required to identify factors affecting complication rates in low-resource environments.


Assuntos
Fissura Palatina/cirurgia , Fístula Bucal/etiologia , Organizações sem Fins Lucrativos , Procedimentos de Cirurgia Plástica/métodos , Padrões de Prática Médica/estatística & dados numéricos , Centros de Atenção Terciária , Canadá , Criança , Pré-Escolar , China , Competência Clínica , Feminino , Humanos , Lactente , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos
7.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 35(3): 296-300, 2017 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-28675016

RESUMO

OBJECTIVE: To characterize the velopharyngeal closure patterns and speech performance among submucous cleft palate patients. METHODS: Patients with submucous cleft palate visiting the Department of Cleft Lip and Palate Surgery, West China Hospital of Stomatology, Sichuan University between 2008 and 2016 were reviewed. Outcomes of subjective speech evaluation including velopharyngeal function, consonant articulation, and objective nasopharyngeal endoscopy including the mobility of soft palate, pharyngeal walls were retrospectively analyzed. RESULTS: A total of 353 cases were retrieved in this study, among which 138 (39.09%) demonstrated velopharyngeal competence, 176 (49.86%) velopharyngeal incompetence, and 39 (11.05%) marginal velopharyngeal incompetence. A total of 268 cases were subjected to nasopharyngeal endoscopy examination, where 167 (62.31%) demonstrated circular closure pattern, 89 (33.21%) coronal pattern, and 12 (4.48%) sagittal pattern. Passavant's ridge existed in 45.51% (76/167) patients with circular closure and 13.48% (12/89) patients with coronal closure. Among the 353 patients included in this study, 137 (38.81%) presented normal articulation, 124 (35.13%) consonant elimination, 51 (14.45%) compensatory articulation, 36 (10.20%) consonant weakening, 25 (7.08%) consonant replacement, and 36 (10.20%) multiple articulation errors. CONCLUSIONS: Circular closure was the most prevalent velopharyngeal closure pattern among patients with submucous cleft palate, and high-pressure consonant deletion was the most common articulation abnormality. Articulation error occurred more frequently among patients with a low velopharyngeal closure rate.


Assuntos
Fissura Palatina , Fala , Insuficiência Velofaríngea , Fenda Labial , Endoscopia , Humanos , Palato Mole , Faringe , Estudos Retrospectivos , Retalhos Cirúrgicos
8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 34(5): 488-492, 2016 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-28326707

RESUMO

OBJECTIVE: To enhance the accuracy in diagnosis and management of submucous cleft palate via a thorough analysis of its anatomical and functional details. METHODS: Two hundred seventy-six submucous cleft palate cases from 2008 to 2014 were retrospectively investigated. Subgroup analysis were performed on the basis of preoperative velopharyngeal function, palatal morphology, cleft lip concurrence, and patient motives for treatment. RESULTS: Among the included cases, 96 (34.78%) were presented as velopharyngeal competence (VPC), 151 (54.71%) as velopharyngeal insufficiency (VPI), and 29 (10.51%) as marginal VPI (MVPI). Eighty cases (28.99%) also demonstrated cleft lip deformity, and 196 cases (71.01%) were merely submucous cleft palate. Compared with patients with submucous cleft palate only, those with cleft lips exhibited higher rates of complete velopharyngeal closure. The pathological spectrum of submucous cleft palate varied significantly. Only 103 (37.32%) cases met all the three diagnostic criteria proposed by Calnan. CONCLUSIONS: Given that the velopharyngeal closure rate varies among the subgroups, the factors analyzed in this study should be considered in the personalized manage-ment of submucous cleft palate.


Assuntos
Fissura Palatina , Insuficiência Velofaríngea , Fenda Labial , Humanos , Estudos Retrospectivos
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(10): 2752-6, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26904812

RESUMO

By extracting the Near Infrared (NIR) diffuse reflectance spectral characteristics from the post-harvest lotus seeds in different storage periods, the quantitative and qualitative analysis were applied to lotus seeds with the Soluble Solids Content (SSC) and dry matter content (DM) as criteria. The results of the Partial Least Squares Regression (PLSR) and distance discrimination (DA) models showed that the absorption spectra of lotus seeds and lotus kernels has clear relations to their SSC and DM. The PLSR models of SSC and DM of lotus seeds had the best performance in 5 941-12 480 cm(-1) spectral region in this study. Their correlation coefficients of prediction were 0.74 and 0.82, and the correlation coefficients of calibration were 0.82 and 0.84, and the correlation coefficients of leave one out cross validation were 0.72 and 0.71. The PLSR model of SSC of lotus kernels was better in 7 891-9 310 cm(-1) spectral region. Its correlation coefficient of prediction was 0.79, and the correlation coefficient of calibration was 0.84, and the correlation coefficient of leave one out cross validation was 0.77. The PLSR model of DM of lotus kernels is better in the full spectral region. Its correlation coefficient of prediction was 0.92, and the correlation coefficient of calibration was 0.89, and the correlation coefficient of leave one out cross validation was 0.82. For lotus seeds, the DA model in 5 400-7 885 cm(-1) spectral region is the best with a correctness of 84.2%. And for lotus kernels, the DA model in 9 226-12 480 cm(-1) spectral region is the best with a correctness of 90.8%. For dry lotus kernels, the discriminant accuracy of the DA model is 98.9% in the optimal spectral region. All kernels with membrane and plumule were correctly discriminated. This research shows that the NIR spectroscopy technique can be used to determine SSC and DM content of lotus seeds and lotus kernels, as well as to discriminate their freshness and also to discriminate dry lotus kernels of different age and the kernels with membrane and plumule.

10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 32(5): 432-5, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25490816

RESUMO

OBJECTIVE: To investigate the correlation between articulation, velopharyngeal function, and surgical age by comparing the changes in articulation after velopharyngeal closure is performed. This study is also conducted to investigate the influencing factors of omission change between pre- and post-operation. METHODS: A total of 48 patients, including 18 males and 30 females, mean age (13.3 ± 5.8) years, with non-syndromic cleft lips and palates were selected from January 2011 to December 2011. Their speech data and articulation between pre- and post-operation were retrospectively analyzed using non-parametric tests. Correlation study was performed to analyze the influencing factors of the changes in articulation. P < 0.05 was considered statistically significant. RESULTS: The difference in articulation after velopharyngeal closure occurred was significant (Z = -3.796, P = 0.000). A negative correlation between the ratio of post-operative normal articulation and surgical age (R = -0.487, P = 0.000) was observed. The change in omission was positively correlated with surgical age (R = 0.589, P = 0.000) and gender (R = 0.404, P = 0.047). By comparison, the change in omission was negatively correlated with follow-up time (R = -0.235, P = 0.040). CONCLUSION: Articulation and intelligibility are significantly improved after velopharyngeal closure is performed. These parameters are negatively correlated with surgical age to some extent. In addition, the change in omission is positively correlated with surgical age and gender, whereas the change in omission is negatively correlated with follow-up time.


Assuntos
Fissura Palatina , Insuficiência Velofaríngea , Adolescente , Transtornos da Articulação , Criança , Fenda Labial , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
11.
Cell Cycle ; 12(6): 935-43, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23421998

RESUMO

HER2/neu oncogene is frequently deregulated in cancers, and the (PI3K)-Akt signaling is one of the major pathways in mediating HER2/neu oncogenic signal. p57 (Kip2) , an inhibitor of cyclin-depependent kinases, is pivotal in regulating cell cycle progression, but its upstream regulators remain unclear. Here we show that the HER2-Akt axis is linked to p57 (Kip2) regulation, and that Akt is a negative regulator of p57 (Kip2) . Ectopic expression of Akt can decrease the expression of p57 (Kip2) , while Akt inhibition leads to p57 (Kip2) stabilization. Mechanistic studies show that Akt interacts with p57 (Kip2) and causes cytoplasmic localization of p57 (Kip2) . Akt phosphorylates p57 on Ser 282 or Thr310. Akt activity results in destabilization of p57 by accelerating turnover rate of p57 and enhancing p57 ubiquitination. Importantly, the negative impact of HER2/Akt on p57 stability contributes to HER2-mediated cell proliferation, transformational activity and tumorigenicity. p57 restoration can attenuate these defects caused by HER2. Significantly, Kaplan-Meier analysis of tumor samples demonstrate that in tumors where HER2 expression was observed, high expression levels of p57 (Kip2) were associated with better overall survival. These data suggest that HER2/Akt is an important negative regulator of p57 (Kip2) , and that p57 restoration in HER2-overexpressing cells can reduce breast tumor growth. Our findings indicate the applicability of employing p57 regulation as a therapeutic intervention in HER2-overexpressing cancers.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Transformação Celular Neoplásica , Inibidor de Quinase Dependente de Ciclina p57/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/metabolismo , Células 3T3 , Animais , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Inibidor de Quinase Dependente de Ciclina p57/genética , Regulação para Baixo , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Transdução de Sinais , Ubiquitinação
12.
Cell Cycle ; 11(24): 4633-41, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23187808

RESUMO

Subunit 6 of the COP9 signalosome complex, CSN6, is known to be critical to the regulation of the MDM2-p53 axis for cell proliferation and anti-apoptosis, but its many targets remain unclear. Here we show that p57 (Kip2) is a target of CSN6, and that CSN6 is a negative regulator of p57 (Kip2) . CSN6 associates with p57 (Kip2) , and its overexpression can decrease the steady-state expression of p57 (Kip2) ; accordingly, CSN6 deficiency leads to p57 (Kip2) stabilization. Mechanistic studies show that CSN6 associates with p57 (Kip2) and Skp2, a component of the E3 ligase, which, in turn, facilitates Skp2-mediated protein ubiquitination of p57 (Kip2) . Loss of Skp2 compromised CSN6-mediated p57 (Kip2) destabilization, suggesting collaboration between Skp2 and CSN6 in degradation of p57 (Kip2) . CSN6's negative impact on p57 (Kip2) elevation translates into cell growth promotion, cell cycle deregulation and potentiated transformational activity. Significantly, univariate Kaplan-Meier analysis of tumor samples demonstrates that high CSN6 expression or low p57 expression is associated with poor overall survival. These data suggest that CSN6 is an important negative regulator of p57 (Kip2) , and that overexpression of CSN6 in many types of cancer could lead to decreased expression of p57 (Kip2) and result in promoted cancer cell growth.


Assuntos
Inibidor de Quinase Dependente de Ciclina p57/metabolismo , Complexos Multiproteicos/metabolismo , Peptídeo Hidrolases/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Complexo do Signalossomo COP9 , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p57/genética , Humanos , Estimativa de Kaplan-Meier , Camundongos , Complexos Multiproteicos/genética , Células NIH 3T3 , Peptídeo Hidrolases/genética , Ligação Proteica/genética , Ligação Proteica/fisiologia
13.
Food Chem Toxicol ; 50(3-4): 492-502, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22142696

RESUMO

In this study, we demonstrated the antioxidant and protective properties of crude extract and fractions from Fructus Ligustri Lucidi (FLL) against hydrogen peroxide (H2O2)-induced oxidative damage in SH-SY5Y cells. The contents of their phytochemical profiles were determined by spectrophotometric methods and high performance liquid chromatography using a photodiode array detector. FLL crude extract possessed appreciable scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl and H2O2. The ethyl acetate (EtOAc) fraction was the most active fraction in scavenging free radicals and H2O2. Following exposure of cells to H2O2, there was a marked decrease in cell survival and intracellular antioxidant enzymes, and then intracellular oxidative stress, the level of lipid peroxidation, and caspase-3 activity were increased. Simultaneous treatment with the EtOAc fraction blocked these H2O2-induced cellular events. Hydroxytyrosol and salidroside are major components of the EtOAc fraction. These results show that the phenolic-enriched EtOAc fraction of FLL contains tyrosol-related derivatives and exerts the protective effects against H2O2 toxicity via its free radical scavenging activity and ability to elevate the levels of antioxidant enzymes.


Assuntos
Acetatos/química , Antioxidantes/farmacologia , Peróxido de Hidrogênio/toxicidade , Medicina Tradicional Chinesa , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Humanos , Peroxidação de Lipídeos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
14.
J Cell Biochem ; 103(4): 1219-30, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17879958

RESUMO

The 5th subunit of COP9 signalosome (CSN5, also known as Jab1 or COPS5) is implicated in regulating p53 activity and is overexpressed in various tumors. However, the precise roles of CSN5 in p53 network and tumorigenesis are not well characterized. Here we show that CSN5 is a critical regulator of both p53 and MDM2. We show that curcumin, an important inhibitor of CSN-associated kinases, can downregulate not only CSN5 but also MDM2, which results in p53 stabilization. Importantly, CSN5 interacts with p53. CSN5 expression leads to p53 degradation, facilitating MDM2-mediated p53 ubiquitination, and promoting p53 nuclear export. Additionally, CSN5 expression results in stabilization of MDM2 through reducing MDM2 self-ubiquitination and decelerating turnover rate of MDM2. Significantly, we further show that CSN5 antagonizes the transcriptional activity of p53. These results demonstrate that CSN5 is a pivotal regulator for both p53 and MDM2. Our studies may pave the way for targeting CSN5 for anti-cancer drug development.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Peptídeo Hidrolases/fisiologia , Proteínas Proto-Oncogênicas c-mdm2/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Transporte Ativo do Núcleo Celular , Complexo do Signalossomo COP9 , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Curcumina/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Ligação Proteica , Ubiquitinação
15.
Cancer Res ; 66(6): 3096-105, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16540659

RESUMO

14-3-3 sigma is induced by tumor suppressor protein p53 in response to DNA damage. p53 can directly transactivate the expression of 14-3-3 sigma to cause a G(2) cell cycle arrest when cell DNA is damaged. The expression of 14-3-3 sigma protein is down-regulated in various tumors, but its function has not been fully established. Protein kinase B/Akt, a crucial regulator of oncogenic signal involved in cell survival and proliferation, is deregulated in many types of cancer. Akt activation can enhance p53 degradation, but its role in DNA damage response is not clear. Here, we show that Akt activation is diminished when p53 and 14-3-3 sigma is up-regulated in response to DNA damage. Evidence is provided that 14-3-3 sigma binds and inhibits Akt. In keeping with this concept, Akt-mediated cell survival is inhibited by 14-3-3 sigma. Significantly, we show that 14-3-3 sigma inhibits Akt-mediated cell growth, transformation, and tumorigenesis. Low expression of 14-3-3 sigma in human primary breast cancers correlates with Akt activation. These data provide an insight into Akt regulation and rational cancer gene therapy by identifying 14-3-3 sigma as a molecular regulator of Akt and as a potential anticancer agent for Akt-activated cancers.


Assuntos
Biomarcadores Tumorais/biossíntese , Transformação Celular Neoplásica/genética , Dano ao DNA/fisiologia , Exonucleases/biossíntese , Proteínas de Neoplasias/biossíntese , Proteína Oncogênica v-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteína Supressora de Tumor p53/biossíntese , Proteínas 14-3-3 , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Processos de Crescimento Celular/fisiologia , Transformação Celular Neoplásica/metabolismo , Ativação Enzimática , Exonucleases/genética , Exonucleases/metabolismo , Exorribonucleases , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Camundongos , Camundongos Nus , Vison , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteína Oncogênica v-akt/metabolismo , Ratos , Proteína Supressora de Tumor p53/genética
16.
J Cell Biochem ; 98(1): 128-38, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16365885

RESUMO

Cyclin-dependent kinase (CDK) inhibitor p27 Kip1, a haplo-insufficient tumor suppressor, is downregulated by oncogenic signal of HER2, a receptor tyrosine kinase oncogene. HER2 promotes mitogenic growth and transformation of cancer cells. HER2 signaling can enhance p27 Kip1 ubiquitination, thereby promoting p27 degradation and subsequent activation of CDK activity. p27 ubiquitination and degradation is enhanced by JAB1 binding as well as by phosphorylation on Thr187. In this study, we generated modified p27 proteins, which are mutated at Thr 187 or deleted at JAB1 binding domain. We applied these modified p27 genes as novel anticancer agents for HER2-overexpressing cells under the control of a tetracycline (tet)-regulated gene expression system. Induction of p27 T187A and p27 T187A DeltaJAB inhibits HER2-activated cell growth, CDK2 activity, cell proliferation, and transformation. Significantly, a modified protein (p27 T187ADeltaJAB) reduced the tumor volume in a HER2-overexpressing tumor model efficiently. These findings demonstrate the applicability of employing modified p27 proteins as a therapeutic intervention in HER2-overexpressing cancers.


Assuntos
Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidores do Crescimento/fisiologia , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Substituição de Aminoácidos/genética , Animais , Complexo do Signalossomo COP9 , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p27/fisiologia , Feminino , Deleção de Genes , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Nus , Mitógenos/fisiologia , Células NIH 3T3 , Peptídeo Hidrolases/genética , Ligação Proteica/genética , Receptor ErbB-2/biossíntese , Treonina/genética , Transfecção
17.
Oncogene ; 24(11): 1924-35, 2005 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-15688030

RESUMO

The FOXO family of Forkhead transcription factors, regulated by the phosphoinositide-3-kinase-Akt pathway, is involved in cell cycle regulation and apoptosis. Strong expression of HER2, a receptor tyrosine kinase oncogene, in cancers has been associated with a poor prognosis. Recently, FOXO4 was shown to regulate the transcription of the cyclin-dependent kinase inhibitor p27 Kip1 gene directly. Also, we have shown that HER2 promotes mitogenic growth and transformation of cancer cells by downregulation of p27 Kip1. Given the fact that FOXO4 mediates p27 transcription, we hypothesize that an Akt phosphorylation mutant of FOXO4 (FOXO4A3), which maintains the activity to transactivate p27 Kip1, may be used as an anticancer agent for HER2-overexpressing cancers. Here, we applied the FOXO4 gene as a novel anticancer agent for HER2-overexpressing cells under the control of a tetracycline (tet)-regulated gene expression system. Overexpression of FOXO4A3 inhibits HER2-activated cell growth. We found that FOXO4A3 inhibited the kinase activity of protein kinase B/Akt and reversed HER2-mediated p27 mislocation in the cytoplasm. FOXO4A3 expression also led to decreased levels of CSN5, a protein involved in p27 degradation. These data suggest that FOXO4A3 also can regulate p27 post-transcriptionally. In addition, we found that FOXO4A3 sensitized cells to apoptosis induced by the chemotherapeutic agent 2-methoxyestradiol. Most significantly for clinical application, FOXO4A3 expression in HER2-overexpressing cells can be regulated in vivo and reduces the tumor volume in a tumor model. These findings indicate the applicability of employing FOXO4 regulation as a therapeutic intervention in HER2-overexpressing cancers.


Assuntos
Proteínas de Transporte/metabolismo , Genes erbB-2/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Células 3T3 , Animais , Proteínas de Transporte/genética , Proteínas de Ciclo Celular , Linhagem Celular , Transformação Celular Neoplásica , Ciclina D1/genética , Inibidor de Quinase Dependente de Ciclina p27 , Fatores de Transcrição Forkhead , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Rim , Camundongos , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt , Fatores de Transcrição/genética
18.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 4052-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281122

RESUMO

The purpose of this study is to develop a M3S- Based GPS navigation system for power wheelchair. The wheelchair steered with GPS and electronic compass can move automatically toward a specific destination through a GIS-Map in the computer. The topic of this study is to help people with disabilities regain independence of transportation in specific areas of their daily activities. This system is now designed to operate in special locations, for example, campuses or airports. Safety of the system is enhanced according to "M3S", which is an international standard for power wheelchair. In the proposed architecture, modules are easily and securely integrated to the wheelchair, which includes a tele-monitor system implemented with computer network, mobile-phone and physiological sensors. Bio-signals, wheelchair location and other information of the user are acquired by the nursing staff or any other medical personnel by using this system.

19.
Oncogene ; 23(42): 7132-43, 2004 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-15273726

RESUMO

HER2/neu, a receptor tyrosine kinase oncogene, promotes mitogenic growth and antiapoptotic activity in cancer cells. Strong expression of HER2/neu in cancers has been associated with poor prognosis. Alternative reading frame protein (ARF), a tumor suppressor protein encoded by a gene located in the Ink4a/ARF gene locus, is frequently inactivated in human cancers. Little is known about the tumor suppressor role of ARF in HER2/neu-overexpressing cancers. Here, we applied the ARF gene as a tumor-suppressive agent for HER2/neu-overexpressing cells under the control of a tetracycline (tet)-regulated gene expression system. We found that ARF antagonized protein kinase B (PKB)/Akt-mediated p27Kip1 phosphorylation and increased p27 stability in HER2/neu-overexpressing cells. ARF expression also led to decreased levels of Cul1 and Skp2, two proteins involved in p27 degradation. We also found that ARF caused apoptosis in HER2/neu-overexpressing cells, and sensitized cells to apoptosis induced by the chemotherapeutic agents taxol and 2-methoxyestradiol. Most significantly for clinical application, we found that ARF inhibited HER2/neu-mediated cell growth, transformation, and tumorigenesis. These findings indicate that modulation of ARF activity may be a useful therapeutic intervention in HER2-overexpressing cancers.


Assuntos
Receptor ErbB-2/genética , Células 3T3 , Animais , Sequência de Bases , Divisão Celular/genética , Linhagem Celular , Linhagem Celular Tumoral , Clonagem Molecular , Primers do DNA , Genes Reporter , Humanos , Camundongos , Camundongos Knockout , Camundongos Nus , Camundongos Transgênicos , Receptor ErbB-2/deficiência , Transfecção , Transplante Heterólogo
20.
Int Immunopharmacol ; 4(5): 649-67, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15120650

RESUMO

The melanoma differentiation associated gene-7 (mda-7) cDNA was isolated by virtue of being induced during melanoma differentiation. Initial gene transfer studies convincingly demonstrated potent antitumor effects of mda-7. Further studies showed that the mechanism of antitumor activity was due to induction of apoptosis. Most striking was the tumor-selective killing by mda-7 gene transfer--normal cells were unaffected by Adenoviral delivery of mda-7 (Ad-mda7). A variety of molecules implicated in apoptosis and intracellular signaling are regulated by Ad-mda7 transduction. Different apoptosis effector proteins are regulated in different tumor types, suggesting that Ad-mda7 may regulate various signaling pathways. mda-7 encodes a secreted protein, MDA-7, which has now been designated as IL-24, and is a novel member of the IL-10 cytokine family. MDA-7/IL-24 protein is actively secreted from cells after mda-7 gene transfer. In human peripheral blood mononuclear cells (PBMC), STAT3 activation by MDA-7/IL-24 is followed by elaboration of secondary Th1 cytokines, demonstrating that MDA-7/IL-24 is a pro-Th1 cytokine. Furthermore, MDA-7/IL-24 is antagonized by the prototypic Th2 cytokine IL-10. MDA-7/IL-24 protein is endogenously expressed in cultured NK and B-cells and is also expressed in dendritic cells in tissues. MDA-7/IL-24 protein is expressed in nevi and melanoma primary tumors, to varying degrees, but is rarely expressed in malignant melanoma or other human tumors evaluated. Indeed, loss of MDA-7/IL-24 protein expression correlates strongly with melanoma tumor invasion and disease progression. The "bystander" effects proposed for MDA-7/IL-24 protein include immune stimulation, antiangiogenesis and receptor-mediated cytotoxicity. Thus, mda-7 is a unique multifunctional cytokine in the IL-10 family and may have potent antitumor utility in a clinical setting.


Assuntos
Citocinas/farmacologia , Genes Supressores de Tumor/efeitos dos fármacos , Interleucina-10/classificação , Interleucinas/classificação , Interleucinas/farmacologia , Citocinas/classificação , Citocinas/genética , Humanos , Interleucina-10/genética , Interleucina-10/farmacologia , Interleucinas/genética
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