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1.
Methods Enzymol ; 690: 445-499, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37858538

RESUMO

Extracellular signal-regulated kinase (ERK) is the culmination of a mitogen-activated protein kinase cascade that regulates cellular processes like proliferation, migration, and survival. Consequently, abnormal ERK signaling often plays a role in the tumorigenesis and metastasis of numerous cancers. ERK inhibition is a sought-after treatment for cancers, especially since clinically approved drugs that target signaling upstream of ERK often induce acquired resistance. Furthermore, the ERK2 isoform may have a differential role in various cancers from the other canonical isoform, ERK1. We demonstrate that small molecules can inhibit ERK2 catalytic and noncatalytic functions by binding to the D-recruitment site (DRS), a protein-protein interaction site distal to the enzyme active site. Using a fluorescence anisotropy-based high-throughput screening, we identify compounds that bind to the DRS and exhibit dose-dependent inhibition of ERK2 activity and ERK2 phosphorylation. We characterize the dose-dependent potency of ERK2 inhibitors using fluorescence anisotropy-based binding assays, fluorescence-based ERK2 substrate phosphorylation assays, and in vitro ERK2 activation assays. In our example, the binding of a DRS inhibitor can be prevented by mutating the DRS residue Cys-159 to serine, indicating that this residue is essential for the interaction. Resulting inhibitors from this process can be assessed in cellular and in vivo experiments for inhibition of ERK signaling and can be evaluated as potential cancer drugs.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular , Transdução de Sinais , Fosforilação , Transdução de Sinais/fisiologia , Processamento de Proteína Pós-Traducional , Isoformas de Proteínas
2.
Int J Tuberc Lung Dis ; 26(9): 869-874, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35996285

RESUMO

BACKGROUND: Rapid diagnosis of drug-resistant TB is critical for early initiation of effective therapy. YD Diagnostics in South Korea recently developed the MolecuTech® REBA MTB-XMDR test to rapidly detect multidrug-resistant TB (MDR-TB), pre-extensively drug-resistant TB (pre-XDR-TB) and resistance to second-line injectable drugs (SLIDs) simultaneously using a fully automated test platform. This study aimed to evaluate the MolecuTech® test for the detection of MDR- and pre-XDR-TB, as well as SLID resistance.METHODS: A total of 151 clinical Mycobacterium tuberculosis isolates from South Korea were tested using the MolecuTech test, and the results were analysed by comparing these with phenotypic drug susceptibility testing (pDST) and sequencing.RESULTS: Compared to pDST, the MolecuTech test showed a sensitivity and specificity of respectively 97.7% and 100.0% for rifampicin (RIF), 82.4% and 100.0% for isoniazid (INH), 97.5% and 97.2% for fluoroquinolones (FQs), and 94.0% and 98.8% for SLIDs. Concordances with the sequencing results of each resistance determinant were 99.3% for RIF, 96.7% for INH, 98.7% for FQs and 99.3% for SLIDs.CONCLUSION: The MolecuTech test is an efficient and reliable rapid molecular diagnostic tool for the simultaneous screening of MDR- and pre-XDR-TB.


Assuntos
Tuberculose Extensivamente Resistente a Medicamentos , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/diagnóstico , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Fluoroquinolonas/uso terapêutico , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Testes de Sensibilidade Microbiana , Rifampina/farmacologia , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
3.
Hernia ; 24(3): 481-488, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31512088

RESUMO

BACKGROUND: Abdominal wall hernias are common in patients with ascites. Elective surgical repair is recommended for the treatment of abdominal wall hernias. However, surgical hernia repair in cirrhotic patients with refractory ascites is controversial. In this study, we aimed to evaluate the outcomes of elective surgical hernia repair in patients with liver cirrhosis with and without refractory ascites. METHOD: From January 2005 to June 2018, we retrospectively reviewed the records of consecutive patients with liver cirrhosis who underwent a surgical hernia repair. RESULTS: This study included 107 patients; 31 patients (29.0%) had refractory ascites. Preoperatively, cirrhotic patients with refractory ascites had a higher median model for end-stage liver disease (MELD) score (13.0 vs 11.0, P = 0.001) than those without refractory ascites. The 30-day mortality rate (3.2% vs 0%, P = 0.64) and the risk of recurrence (hazard ratio 0.410; 95% CI 0.050-3.220; P = 0.39) did not differ significantly between cirrhotic patients with refractory ascites and cirrhotic patients without refractory ascites. Among cirrhotic patients with refractory ascites, albumin (P = 0.23), bilirubin (P = 0.37), creatinine (P = 0.97), and sodium levels (P = 0.35) did not change significantly after surgery. CONCLUSION: In advanced liver cirrhosis patients with refractory ascites, hernias can be safely treated with elective surgical repair. Mortality rate within 30 days did not differ by the presence or absence of refractory ascites. Elective hernia repair might be beneficial for treatment of abdominal wall hernia in cirrhotic patients with refractory ascites.


Assuntos
Ascite , Hérnia Ventral/cirurgia , Herniorrafia , Cirrose Hepática , Idoso , Ascite/etiologia , Ascite/mortalidade , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Hérnia Ventral/complicações , Hérnia Ventral/mortalidade , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Herniorrafia/mortalidade , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos Retrospectivos , Telas Cirúrgicas , Resultado do Tratamento
4.
J Viral Hepat ; 25(10): 1161-1171, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29741286

RESUMO

Nucleot(s)ide analogues (NAs) reduce the risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients. However, the risk of HCC is reportedly higher for NA-treated patients than for patients in the inactive CHB phase. This study aimed to compare the long-term outcomes of CHB patients with NA-induced viral suppression and those of patients with inactive CHB. This retrospective study involved 1118 consecutive CHB patients whose HBV DNA level was continuously <2000 IU/mL during follow-up with/without antiviral agents. The patients were classified into inactive CHB (n = 373) or NA groups (n = 745). The primary endpoint was overall survival. Secondary endpoints included development of HCC and other liver-related events. The median duration of follow-up was 41.0 (interquartile range = 26.5-55.0) months. The difference in overall survival between the NA group vs. the inactive CHB group was not significant (hazard ratio [HR] = 0.78; 95% confidence interval [CI] = 0.33-1.85; P = .57). The NA group showed a significantly higher risk of HCC (HR = 3.44; 95% CI = 1.82-6.52; P < .01), but comparable risk for non-HCC liver-related events (HR = 1.02; 95% CI = 0.66-1.59; P = .93), compared with the inactive CHB group. Among patients with cirrhosis, the NA group showed a significantly lower risk of death (HR = 0.31; 95% CI = 0.097-0.998; P = .05) and non-HCC liver-related events (HR = 0.51; 95% CI = 0.31-0.83; P < .01), but a slightly higher risk of HCC (HR = 2.39; 95% CI = 0.85-6.75; P = .09), compared to the inactive CHB group. The overall survival of untreated patients with inactive CHB and of CHB patients achieving viral suppression with NA was comparable. However, NA treatment of cirrhotic patients was significantly associated with longer overall survival and lower risk of liver-related events.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/mortalidade , Nucleosídeos/uso terapêutico , Adulto , Idoso , Antivirais/efeitos adversos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , DNA Viral/sangue , Feminino , Seguimentos , Hepatite B Crônica/epidemiologia , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Nucleosídeos/efeitos adversos , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Resultado do Tratamento
5.
Aliment Pharmacol Ther ; 47(11): 1490-1501, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29611209

RESUMO

BACKGROUND: Data are insufficient regarding the survival benefit of surveillance for hepatocellular carcinoma (HCC). AIM: To investigate the effectiveness of HCC surveillance in a hepatitis B-endemic population. METHODS: This retrospective cohort study included 1402 consecutive patients who were newly diagnosed with HCC between 2005 and 2012 at a single tertiary hospital in Korea. The primary endpoint was overall survival. Lead-time and length-time biases were adjusted (sojourn time = 140 days) and sensitivity analyses were performed. RESULTS: The most common aetiology was hepatitis B (80.4%). Cirrhosis was present in 78.2%. HCC was diagnosed during regular surveillance (defined as mean interval of ultrasonography <8 months, n = 834), irregular surveillance (n = 104) or nonsurveillance (n = 464). Patients in the regular surveillance group were diagnosed at earlier stages ([very] early stage, 64.4%) than the irregular surveillance (40.4%) or nonsurveillance (26.9%) groups and had more chance for curative treatments (52.4%) than the irregular surveillance (39.4%) or nonsurveillance (23.3%) groups (all P < 0.001). Mortality risk was significantly lower in the regular surveillance group (adjusted hazard ratio [aHR], 0.69; 95% [CI], 0.57-0.83) but not in the irregular surveillance group (aHR, 0.94; 95% CI, 0.69-1.28) compared with the nonsurveillance group after adjusting for confounding factors and lead-time. When the subjects were restricted to cirrhotic patients or Child-Pugh class A/B patients, similar results were obtained for mortality risk reduction between groups. CONCLUSIONS: HCC surveillance was associated with longer survival owing to earlier diagnosis and curative treatment. Survival advantage was significant with regular surveillance but not with irregular surveillance.


Assuntos
Carcinoma Hepatocelular/mortalidade , Hepatite B/mortalidade , Neoplasias Hepáticas/mortalidade , Vigilância da População , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico , Diagnóstico Precoce , Feminino , Hepatite B/diagnóstico , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/mortalidade , Neoplasias Hepáticas/diagnóstico , Pessoa de Meia-Idade , Vigilância da População/métodos , República da Coreia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências
6.
J Viral Hepat ; 25(6): 707-717, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29316069

RESUMO

Nucleos(t)ide analogues (NAs) have been shown to decrease the risk of hepatocellular carcinoma (HCC) recurrence. This study evaluated whether high-potency NAs (entecavir and tenofovir disoproxil fumarate [TDF]) reduce the risk of tumour recurrence more potently than low-potency NAs after curative treatment of hepatitis B virus (HBV)-related HCC. This study included 607 consecutive HBV-related HCC patients treated with surgical resection or radiofrequency ablation. The patients were categorized into three groups according to antiviral treatment: group A (no antiviral; n = 261), group B (low-potency NA; n = 90) and group C (high-potency NA; n = 256). The primary end-point was recurrence-free survival (RFS). During the duration of follow-up, the median RFS was 29.4, 25.1, and 88.2 months in groups A, B and C, respectively (P < .001, log-rank test). The multivariate Cox analysis indicated that group C had a significantly longer RFS than both group A (adjusted hazard ratio [HR] = 0.39, P < .001) and group B (adjusted HR = 0.47, P < .001). When baseline characteristics were balanced using inverse probability weighting, group C still had a significantly longer RFS than group A (adjusted HR = 0.46, P < .001) and group B (adjusted HR = 0.59, P = .007). Group C had significantly lower risk of viral breakthrough than group B (HR = 0.19, P < .001). Viral breakthrough was an independent risk factor for shorter RFS among groups B and C (adjusted HR = 2.03, P = .007, time-dependent Cox analysis). Antiviral agents with high genetic barrier to resistance (entecavir and TDF) reduced the risk of HCC recurrence compared with other antivirals and no antiviral treatment, especially in patients with high baseline viral load.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/prevenção & controle , Guanina/análogos & derivados , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Tenofovir/uso terapêutico , Idoso , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/cirurgia , Estudos de Coortes , Feminino , Guanina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Prevenção Secundária , Resultado do Tratamento
7.
J Viral Hepat ; 25(5): 552-560, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29194870

RESUMO

The treatment option in chronic hepatitis B (CHB) patients with persistent low-level viremia despite entecavir or tenofovir monotherapy is unclear. This study investigated the development of hepatocellular carcinoma (HCC) or cirrhosis in hepatitis B e antigen (HBeAg)-positive high viral load CHB patients, according to the time needed to achieve complete viral suppression. A total of 325 HBeAg-positive CHB patients with high viral load who were recently started on antiviral therapy with entecavir or tenofovir were included. The enrolled patients were divided into 2 groups with 4 separate criteria based on the time needed to achieve complete viral suppression: within 1, 2, 3 or 4 years of therapy initiation. The outcomes were development of HCC and cirrhosis. The cumulative incidence of HCC was significantly higher in patients failing complete viral suppression within 1 year (hazard ratio (HR), 4.54; 95% confidence interval (CI), 1.03-19.93; P = .045) or 2 years (HR, 3.38; 95% CI, 1.24-9.23; P = .018), than patients who achieved complete viral suppression within 1 or 2 years, respectively. Cumulative incidence of cirrhosis was also significantly higher in patients failing suppression within 1 year (HR, 1.95; 95% CI, 1.04-3.66; P = .037) or 2 years (HR, 2.44; 95% CI, 1.41-4.22; P = .001). When the time for achieving viral suppression exceeded 2 years, the cumulative incidence of HCC or cirrhosis was not different regardless of viral suppression. Complete hepatitis B virus suppression within 2 years of antiviral therapy initiation is associated with risk reduction in HCC or cirrhosis development.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Carga Viral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hepatite B Crônica/complicações , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resposta Viral Sustentada , Fatores de Tempo , Adulto Jovem
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 1962-1965, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060278

RESUMO

A temporary dental implant is a medical device which is temporarily used to support a prosthesis such as an artificial tooth used for restoring patient's masticatory function during implant treatment. It is implanted in the oral cavity to substitute for the role of tooth. Due to the aging and westernization of current Korean society, the number of tooth extraction and implantation procedures is increasing, leading to an increase in the use and development of temporary dental implants. Because an implant performs a masticatory function in place of a tooth, a dynamic load is repeatedly put on the implant. Thus, the fatigue of implants is reported to be the most common causes of the fracture thereof. According to the investigation and analysis of the current domestic and international standards, the standard for fatigue of implant fixtures is not separately specified. Although a test method for measuring the fatigue is suggested in an ISO standard, it is a standard for permanent dental implants. Most of the test standards for Korean manufacturers and importers apply 250 N or more based on the guidance for the safety and performance evaluation of dental implants. Therefore, this study is intended to figure out the fatigue standard which can be applied to temporary dental implants when measuring the fatigue according to the test method suggested in the permanent dental implant standard. The results determined that suitable fatigue standards of temporary dental implants should be provided by each manufacturer rather than applying 250 N. This study will be useful for the establishment of the fatigue standards and fatigue test methods of the manufacturers and importers of temporary dental implants.


Assuntos
Implantes Dentários , Implantação Dentária Endóssea , Implantes Dentários para Um Único Dente , Falha de Restauração Dentária , Humanos
9.
Aliment Pharmacol Ther ; 46(9): 845-855, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28836723

RESUMO

BACKGROUND: Rifaximin might decrease the risk of portal hypertension-related complications by controlling small intestinal bacterial overgrowth. AIM: To evaluate whether rifaximin was associated with the risk of death and cirrhotic complications. METHODS: We conducted a retrospective study that included 1042 patients experiencing hepatic encephalopathy (HE): 421 patients without hepatocellular carcinoma (HCC; the non-HCC cohort) and 621 patients with HCC (the HCC cohort). The primary endpoint was overall survival and secondary endpoints were recurrence of HE and the development of spontaneous bacterial peritonitis (SBP), hepatorenal syndrome (HRS) and variceal bleeding. RESULTS: In the non-HCC cohort, 145 patients received rifaximin plus lactulose (the rifaximin group) and 276 patients received lactulose alone (the control group). The multivariate analysis revealed that rifaximin was significantly associated with lower risk of death (adjusted hazard ratio [aHR], 0.697; P = .024) and reduced the risk of recurrent HE (aHR, 0.452; P < .001), SBP (aHR, 0.210; P < .001) and variceal bleeding (aHR, 0.425; P = .011) but not HRS (aHR, 0.598; P = .08). In the HCC cohort, 173 patients received rifaximin plus lactulose and 448 patients received lactulose. Rifaximin was not associated with the risk of death (aHR, 1.177; P = .121). Rifaximin was associated with lower risk of SBP (aHR, 0.323; P < .001) but not with variceal bleeding (aHR, 0.660; P = .104) or recurrent HE (aHR, 0.689; P = .057). The risk of Clostridium difficile-associated diarrhoea was not different between the groups (aHR, 0.028; P = .338). CONCLUSIONS: In patients without HCC, rifaximin treatment was significantly associated with prolonged overall survival and reduced risks of spontaneous bacterial peritonitis, variceal bleeding and recurrent hepatic encephalopathy.


Assuntos
Anti-Infecciosos/uso terapêutico , Encefalopatia Hepática/tratamento farmacológico , Rifamicinas/uso terapêutico , Idoso , Infecções Bacterianas/prevenção & controle , Carcinoma Hepatocelular/tratamento farmacológico , Varizes Esofágicas e Gástricas/prevenção & controle , Feminino , Encefalopatia Hepática/complicações , Humanos , Lactulose/uso terapêutico , Cirrose Hepática/etiologia , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Peritonite/prevenção & controle , Recidiva , Estudos Retrospectivos , Rifaximina , Prevenção Secundária
10.
Eur J Clin Microbiol Infect Dis ; 36(11): 2063-2072, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28620844

RESUMO

Mycobacterium tuberculosis (Mtb) in sputum originates from lung cavities in tuberculosis (TB) patients. But drug susceptibility testing (DST) of sputum Mtb can not be conducted the same as in the lung because mutagenesis of bacilli may be happening in the lung during treatment and result in the possibility of the presence of heterogeneous drug-resistant subpopulations in the different lung lesions. This could be one of the reasons for low cure rates for multi-drug resistant (MDR)-TB. We studied the resected lungs of nine surgery patients with chronic TB. The isolates isolated from the sputum and different lung lesions of each patient were tested for phenotypic DST and genotyped using restriction fragment length polymorphism (RFLP) typing method. Genetic analysis to resistance to first and second line drugs was also performed. Five of nine patients were MDR-TB and three XDR-TB. DST results for ten anti-TB drugs were in accordance among different lung lesions in eight patients. However, only three of these eight patients showed the concordance of DST with sputum. Even though the isolates were heteroresistant, genotyping them by RFLP showed the clonal population in each individual patient. Six of eight followed-up patients achieved successful cure. In conclusion, the heteroresistance between sputum and lung lesions and a clonal population without mixed infection might provide useful information in establishing treatment regimen and surgery decision for MDR- and XDR-TB.


Assuntos
Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/genética , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Adulto , Feminino , Humanos , Pulmão/microbiologia , Pulmão/patologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Polimorfismo de Fragmento de Restrição , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Pulmonar/microbiologia , Adulto Jovem
11.
Cell Death Dis ; 6: e1964, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26539911

RESUMO

Novel therapeutic strategies are needed to overcome cancer recurrence, metastasis, and resistance to chemo- and radiotherapy. Cancer stem cells (CSCs) are major contributors to the malignant transformation of cells due to their capacity for self-renewal. Although various CSC markers have been identified in several types of tumors, they are primarily used as cancer-prediction markers and for the isolation of CSC populations. CD133, one of the best-characterized CSC markers in distinct solid tumor types, was shown to be correlated with CSC tumor-initiating capacity; however, the regulation of CD133 expression and its function in cancer are poorly understood. Here, we show that CD133 expression is negatively regulated by direct binding of the p53 tumor suppressor protein to a noncanonical p53-binding sequence in the CD133 promoter. Binding of p53 recruits Histone Deacetylase 1 (HDAC1) to the CD133 promoter and subsequently suppresses CD133 expression by reducing histone H3 acetylation. Furthermore, CD133 depletion suppresses tumor cell proliferation, colony formation, and the expression of core stemness transcription factors including NANOG, octamer-binding transcription factor 4 (OCT4), SOX2, and c-MYC. Critically, the anti-proliferative effects of p53 are antagonized by rescue of CD133 expression in a p53 overexpressing cell line, indicating that the tumor suppressive activity of p53 might be mediated by CD133 suppression. Taken together, our results suggest that p53-mediated transcriptional regulation of CD133 is a key underlying mechanism for controlling the growth and tumor-initiating capacity of CSCs and provide a novel perspective on targeting CSCs for cancer therapy.


Assuntos
Antígenos CD/genética , Glicoproteínas/genética , Células-Tronco Neoplásicas/fisiologia , Peptídeos/genética , Proteína Supressora de Tumor p53/genética , Antígeno AC133 , Antígenos CD/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Glicoproteínas/metabolismo , Células HeLa , Humanos , Células Jurkat , Células MCF-7 , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Peptídeos/metabolismo , Proteína Supressora de Tumor p53/metabolismo
12.
Nutr Metab Cardiovasc Dis ; 24(11): 1240-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25096924

RESUMO

BACKGROUNDS AND AIMS: C-reactive protein (CRP) levels predict incident and recurrent cardiovascular disease (CVD) events; however, associations between CRP and pre-clinical atherosclerosis is less certain. Since high concentrations of high-density lipoprotein cholesterol (HDL-C) are inversely associated with CVD risk, we investigated whether HDL-C modified the association between CRP concentration and measures of preclinical atherosclerosis. METHODS AND RESULTS: Data were analyzed from a Korean occupational cohort of 12,030 male subjects who underwent a cardiac computed tomography (CT) estimation of coronary artery calcification (CAC) score and an assessment of CVD risk factors. Logistic regression was used to describe associations between CRP and measures of pre-clinical atherosclerosis, such as CAC scores >0. As many as 1351 (11.2%) participants had a CAC score>0. CRP was stratified into 3 groups based on clinical category: <1 mg/L, 1 to <2 mg/L, and ≥ 2 mg/dL. In the bottom CRP group, 907/8697 (10.4%) of subjects had a CAC score >0, compared with 242/1943 (12.5%) in the middle group and 202/1396 (14.5%) in the top CRP group (p < 0.0001). After adjustment for multiple CVD risk factors, there was a positive association between CRP and CAC score>0 (OR between top and bottom CRP groups, 1.41 [1.04, 1.90], p = 0.027) in the lowest HDL-C quartile but not in the highest HDL-C (OR between top and bottom CRP group, 0.80 [0.46, 1.39], p = 0.425). CONCLUSION: The association between CRP concentration and CAC score differed according to HDL-C levels.


Assuntos
Aterosclerose/sangue , Proteína C-Reativa/metabolismo , Cálcio/sangue , HDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Adulto , Idoso , Aterosclerose/diagnóstico , LDL-Colesterol/sangue , Estudos de Coortes , Doença da Artéria Coronariana/diagnóstico , Estudos Transversais , Voluntários Saudáveis , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , República da Coreia , Inquéritos e Questionários , Triglicerídeos/sangue
13.
Oncogene ; 33(1): 108-15, 2014 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23178491

RESUMO

Checkpoint kinase 2 (CHK2) kinase is a key mediator in many cellular responses to genotoxic stresses, including ionizing radiation (IR) and topoisomerase inhibitors. Upon IR, CHK2 is activated by ataxia telangiectasia mutated kinase and regulates the S-phase and G1-S checkpoints, apoptosis and DNA repair by phosphorylating downstream target proteins, such as p53 and Brca1. In addition, CHK2 is thought to be a multi-organ cancer susceptibility gene. In this study, we used a tandem affinity purification strategy to identify proteins that interact with CHK2 kinase. Cyclin-dependent kinase 11 (CDK11)(p110) kinase, implicated in pre-mRNA splicing and transcription, was identified as a CHK2-interacting protein. CHK2 kinase phosphorylated CDK11(p110) on serine 737 in vitro. Unexpectedly, CHK2 kinase constitutively phosphorylated CDK11(p110) in a DNA damage-independent manner. At a molecular level, CDK11(p110) phosphorylation was required for homodimerization without affecting its kinase activity. Overexpression of CHK2 promoted pre-mRNA splicing. Conversely, CHK2 depletion decreased endogenous splicing activity. Mutation of the phosphorylation site in CDK11(p110) to alanine abrogated its splicing-activating activity. These results provide the first evidence that CHK2 kinase promotes pre-mRNA splicing via phosphorylating CDK11(p110).


Assuntos
Quinase do Ponto de Checagem 2/fisiologia , Quinases Ciclina-Dependentes/metabolismo , Precursores de RNA/genética , RNA Mensageiro/genética , Sequência de Aminoácidos , Quinase do Ponto de Checagem 2/química , Quinases Ciclina-Dependentes/química , Dano ao DNA , Células HEK293 , Células HT29 , Humanos , Fosforilação , Mapeamento de Interação de Proteínas , Multimerização Proteica , Processamento de Proteína Pós-Traducional , Precursores de RNA/metabolismo , Splicing de RNA , RNA Mensageiro/metabolismo
14.
Cell Death Dis ; 4: e583, 2013 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-23579270

RESUMO

Menin, encoded by the multiple endocrine neoplasia type 1 (MEN1) gene, is a tumor suppressor that leads to multiple endocrine tumors upon loss of its function. Menin functions as a transcriptional activator by tethering MLL complex to mediate histone H3 K4 methylation. It also functions as a repressor. However, the molecular mechanism of how menin contributes to the opposite outcome in gene expression is largely unknown. Here, we investigated the role of menin in the epigenetic regulation of transcription mediated by histone covalent modification. We show that the global methylation level of histone H3 K9, as well as H3 K4, was decreased in Men1(-/-) MEF cells. Consistently, menin was able to interact with the suppressor of variegation 3-9 homolog family protein, SUV39H1, to mediate H3 K9 methylation. This interaction decreased when patient-derived MEN1 mutation was introduced into the SUV39H1-interaction domain. We show that menin mediated different chromatin changes depending on target genes. Chromatin immunoprecipitation studies showed that menin directly associated with the GBX2 promoter and menin-dependent recruitment of SUV39H1 was essential for chromatin remodeling and transcriptional regulation. These results provide a molecular basis of how menin functions as a transcriptional repressor and suggest that menin-dependent integration of H3 K9 methylation might play an important role in preventing tumors.


Assuntos
Transformação Celular Neoplásica/metabolismo , Montagem e Desmontagem da Cromatina , Epigênese Genética , Histonas/metabolismo , Lisina/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Transformação Celular Neoplásica/genética , Fibroblastos/metabolismo , Fibroblastos/patologia , Células HEK293 , Histonas/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Lisina/genética , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Mutação , Transporte Proteico , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais
15.
Bone Marrow Transplant ; 48(1): 68-73, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22635247

RESUMO

From January 2004 to December 2008, 50 consecutive patients with high-risk neuroblastoma were assigned to receive tandem HDCT (high-dose chemotherapy)/auto-SCT after nine cycles of induction chemotherapy. CEC (carboplatin + etoposide + cyclophosphamide) regimen and TM (thiotepa + melphalan)-TBI regimen (or TM regimen for stage 3 patients) were the first and second HDCT regimens. Local radiotherapy, differentiation therapy with 13-cis-retinoid acid and immunotherapy with interleukin-2 were given after tandem HDCT/auto-SCT. Of the 50 patients, 49 underwent a first HDCT/auto-SCT and 47 underwent a second HDCT/auto-SCT. The tumor relapsed or progressed in 14 patients, secondary malignancy developed in one patient and one patient died from chronic lung disease. Therefore, 34 patients remained event free with a median follow-up of 54.5 months (range, 14-94 months) from diagnosis. The probabilities of 5-year OS and EFS for all 50 patients were 77.0% (95% confidence interval (CI), 63.7-90.3) and 71.4% (95% CI, 58.7-84.1), respectively. However, all patients who remained event free for >3 years after tandem HDCT/auto-SCT experienced late adverse effects. Chemotherapeutic dose-escalation strategy using tandem HDCT/auto-SCT was very encouraging for survival. However, further studies incorporating newer treatment modalities are needed to reduce late adverse effects without jeopardizing the survival rate.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia de Indução , Neuroblastoma/terapia , Radioterapia/métodos , Transplante de Células-Tronco , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Criança , Pré-Escolar , Terapia Combinada/efeitos adversos , Variações do Número de Cópias de DNA , Estudos de Viabilidade , Humanos , Quimioterapia de Indução/efeitos adversos , Lactente , Interleucina-2/administração & dosagem , Interleucina-2/efeitos adversos , Interleucina-2/uso terapêutico , Isotretinoína/administração & dosagem , Isotretinoína/efeitos adversos , Isotretinoína/uso terapêutico , Proteína Proto-Oncogênica N-Myc , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Estadiamento de Neoplasias , Neuroblastoma/diagnóstico , Neuroblastoma/patologia , Neuroblastoma/secundário , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Prognóstico , Estudos Prospectivos , Radioterapia/efeitos adversos , Transplante de Células-Tronco/efeitos adversos , Análise de Sobrevida , Transplante Autólogo , Irradiação Corporal Total/efeitos adversos
16.
J Int Med Res ; 39(5): 1808-15, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22117981

RESUMO

Total intravenous anaesthesia (TIVA) can reduce the risk of postoperative nausea and vomiting (PONV) almost as much as a single antiemetic. This study compared TIVA (using propofol and remifentanil) with prophylactic palonosetron (a 5-hydroxytryptamine type 3 receptor antagonist) combined with inhalation anaesthesia using sevoflurane in 50% nitrous oxide, for the prevention of PONV. Patients were randomly assigned to one of two prophylactic interventions: (i) palonosetron 0.075 mg, intravenously before induction of inhalation anaesthesia (palonosetron group); and (ii) TIVA (propofol target blood concentration 2.5-6.0 µg/ml; remifentanil target blood concentration 2.5-6.0 ng/ml; TIVA group). Nausea/vomiting occurrence and severity were monitored immediately after the end of surgery for 24 h. The incidence of PONV was around 50% in both groups and the severity of nausea was similar in both groups. Prophylactic palonosetron with inhalational anaesthesia using sevoflurane in 50% nitrous oxide reduced the incidence of PONV after gynaecological laparoscopic surgery almost as much as TIVA using propofol and remifentanil.


Assuntos
Anestésicos Combinados , Anestésicos Inalatórios , Anestésicos Intravenosos , Antieméticos/administração & dosagem , Náusea e Vômito Pós-Operatórios/prevenção & controle , Adulto , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Isoquinolinas/administração & dosagem , Laparoscopia , Éteres Metílicos/administração & dosagem , Pessoa de Meia-Idade , Óxido Nitroso/administração & dosagem , Palonossetrom , Piperidinas/administração & dosagem , Propofol/administração & dosagem , Quinuclidinas/administração & dosagem , Remifentanil , Sevoflurano
17.
J Int Med Res ; 39(2): 399-407, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21672343

RESUMO

This randomized, double-blind study evaluated the relative efficacy of palonosetron (a new, selective 5-hydroxytryptamine type 3 [5-HT(3)] receptor antagonist) and ondansetron in preventing postoperative nausea and vomiting (PONV) in patients undergoing gynaecological laparoscopic surgery. Patients received either palonosetron 0.075 mg (n = 45) or ondansetron 8 mg (n = 45), intravenously, immediately before induction of general anaesthesia. The occurrence of nausea and vomiting and the severity of nausea according to a visual analogue scale were monitored immediately after the end of surgery and during the following 24 h. The incidence of PONV was significantly lower in the palonosetron group compared with the ondansetron group (42.2% vs 66.7%, respectively). There were no significant statistical differences in the visual analogue scale for nausea. In conclusion, palonosetron 0.075 mg was more effective than ondansetron 8 mg in preventing PONV.


Assuntos
Antieméticos/uso terapêutico , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Isoquinolinas/uso terapêutico , Laparoscopia/efeitos adversos , Ondansetron/uso terapêutico , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Náusea e Vômito Pós-Operatórios/prevenção & controle , Quinuclidinas/uso terapêutico , Adulto , Anestesia , Antieméticos/administração & dosagem , Demografia , Método Duplo-Cego , Feminino , Humanos , Incidência , Injeções Intravenosas , Isoquinolinas/administração & dosagem , Ondansetron/administração & dosagem , Palonossetrom , Satisfação do Paciente , Náusea e Vômito Pós-Operatórios/epidemiologia , Quinuclidinas/administração & dosagem , Resultado do Tratamento
18.
Oncogene ; 30(28): 3127-38, 2011 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-21358672

RESUMO

Germline mutations in the von Hippel-Lindau (VHL) tumor suppressor gene cause VHL disease, a rare and autosomal-dominant genetic syndrome. Because VHL protein (pVHL) is the master regulator of hypoxia-inducible factor alpha (HIFα), the most prominent feature of VHL disease is the deregulation of HIFα proteins. However, the precise mechanism by which the loss of pVHL function contributes to tumorigenesis is not fully understood. Here, we show that pVHL destabilizes the F-box protein Skp2, a chief component of Skp, Cullin, F-box-containing complex that promotes DNA synthesis in the S phase. The ß-domain of pVHL interacts with Skp2, stimulating proteasome-dependent Skp2 degradation, but the destabilization of Skp2 does not depend on the E3 ubiquitin ligase activity of pVHL. Notably, the generation of DNA damage induces Skp2 degradation, which is attenuated by the suppression of endogenous pVHL expression. One possible mechanism of pVHL-dependent Skp2 degradation entails the antagonizing of Akt-mediated Skp2 phosphorylation, which maintains Skp2 stability. Reintroduction of VHL into VHL-null renal cell carcinoma (RCC) cells decreased Skp2 levels and restored DNA damage-dependent Skp2 degradation. These results identify the tumor suppressor function of pVHL in delaying the S-phase progression to inhibit cell proliferation on DNA damage. Clinically, this report explains as to why Skp2 accumulates abnormally in RCC tissues.


Assuntos
Dano ao DNA , Proteínas Quinases Associadas a Fase S/química , Proteínas Quinases Associadas a Fase S/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Apoptose , Carcinoma de Células Renais/patologia , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Humanos , Neoplasias Renais/patologia , Cinética , Fosforilação , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fase S , Ubiquitinação
19.
Drug Discov Ther ; 5(3): 109-18, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22466239

RESUMO

Senescence-accelerated mouse prone/8 (SAMP8), a murine model of accelerated senescence, shows age-related deficits in learning and memory. The oral administration of oligomers improved spatial and object recognition impairment in SAMP8. The expression of phosphorylated neurofilament-H was significantly elevated in the hippocampal CA1. This indicates that oligomers induce an increase in the density of axons. To investigate the protective mechanisms of oligomers against brain dysfunction with aging, we carried out a receptor tyrosine kinase phosphorylation antibody array, and clarified that the administration of oligomers led to an increase in the phosphorylation of vascular endothelial growth factor receptor (VEGFR)-2, suggesting the neuroprotective role of oligomers. The phosphorylation of VEGFR-2 was more markedly increased in the hypothalamus and choroid plexus than in other brain regions of SAMP8. Memory in oligomer-treated mice was impaired by SU1498, a VEGFR-2-specific antagonist. Elucidating the relationship between memory impairment with aging and VEGFR-2 signaling may provide new suggestions for protection against memory deficit in the aging brain. In addition, we revealed that the administration of oligomers extended the life span of SAMP8. Oligomers elevated SIRT1 expression, which is recognized as an essential factor for life span extension in the brain. However, the administration of oligomers did not induce stereotypical behaviors such as rearing, jumping, or hanging from the lid of a cage, while food restriction increased these frequencies without a significant change in motor function. The present study suggests the promising role of oligomers as an anti-aging agent to extend life span.

20.
J Med Food ; 12(1): 124-30, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19298205

RESUMO

To ascertain the principal active peroxynitrite (ONOO(-)) scavenging components of heat-processed Panax ginseng C.A. Meyer (sun ginseng [SG]), the ONOO(-) scavenging activities of fractions and components of SG were compared. The results demonstrated that the ONOO(-) scavenging ability of SG was due to its ether fraction containing phenolic compounds. High-performance liquid chromatography analysis and ONOO(-) scavenging activity tests of the phenolic acids contained in SG identified vanillic acid, ferulic acid, p-coumaric acid, syringic acid, and maltol as the main active ONOO(-) scavenging components of SG. The ONOO(-) scavenging activities of phenolic acids and maltol were dependent on the degrees of their proton donating ability.


Assuntos
Sequestradores de Radicais Livres/farmacologia , Panax/química , Ácido Peroxinitroso/metabolismo , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Ácidos Cumáricos/isolamento & purificação , Ácidos Cumáricos/farmacologia , Ácido Gálico/análogos & derivados , Ácido Gálico/isolamento & purificação , Ácido Gálico/farmacologia , Fenóis/isolamento & purificação , Extratos Vegetais/química , Propionatos , Pironas/isolamento & purificação , Pironas/farmacologia , Ácido Vanílico/isolamento & purificação , Ácido Vanílico/farmacologia
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