RESUMEN
BACKGROUND: Microarray data with reference to gene expression profiles have provided some valuable results related to a variety of problems, and contributed to advances in clinical medicine. Microarray data characteristically have a high dimension and small sample size, which makes it difficult for a general classification method to obtain correct data for classification. However, not every gene is potentially relevant for distinguishing the sample class. Thus, in order to analyze gene expression profiles correctly, feature (gene) selection is crucial for the classification process, and an effective gene extraction method is necessary for eliminating irrelevant genes and decreasing the classification error rate. OBJECTIVE: The purpose of gene expression analysis is to discriminate between classes of samples, and to predict the relative importance of each gene for sample classification. METHOD: In this paper, correlation-based feature selection (CFS) and Taguchi-binary particle swarm optimization (TBPSO) were combined into a hybrid method, and the K-nearest neighbor (K-NN) with leave-one-out cross-validation (LOOCV) method served as a classifier for ten gene expression profiles. RESULTS: Experimental results show that this hybrid method effectively simplifies feature selection by reducing the number of features needed. The classification error rate obtained by the proposed method had the lowest classification error rate for all of the ten gene expression data set problems tested. For six of the gene expression profile data sets a classification error rate of zero could be reached. CONCLUSION: The introduced method outperformed five other methods from the literature in terms of classification error rate. It could thus constitute a valuable tool for gene expression analysis in future studies.
Asunto(s)
Perfilación de la Expresión Génica/clasificación , Análisis de Secuencia por Matrices de Oligonucleótidos/clasificación , Perfilación de la Expresión Génica/estadística & datos numéricos , Humanos , Modelos Estadísticos , Análisis de Secuencia por Matrices de Oligonucleótidos/estadística & datos numéricosRESUMEN
The objective was to develop high-throughput gender identification of eagles. Based on BLAST and alignment analyses, the CHD-Z and CHD-W sequences of nine species of eagles were highly homologous with Spilornis cheela hoya (S. c. hoya); therefore, TaqMan probes were designed to target their CHD-ZW-common and CHD-W-specific regions. In S. c. hoya, genders were identified using TaqMan-based, real-time PCR (amplified by P2/P8 primers); this method was validated with anatomically confirmed controls (one of each gender). Both genders had high intensities of the HEX-labeled (CHD-ZW-common) probe, whereas only females had high intensity of the FAM-labeled (CHD-W-specific) probe. The sequence of the CHD-W-specific probe designed for S. c. hoya was completely homologous with the CHD-W-specific region in Circaetus gallicus, Gyps indicus, and Gyps bengalensis, and was only one nucleotide different from those of Accipiter nisus, Spizaetus nipalensis, Aquila chrysaetos, Circus spilonotus, and Milvus migrans. For the CHD-ZW-common probe, all species listed were completely conserved. Using real-time PCR software, we established auto-calling of the genders of 15 individuals of S. c. hoya. In conclusion, this method provided accurate, high-throughput gender identification for S. c. hoya, and has considerable potential for identifying the gender of several related species of eagles.
Asunto(s)
Águilas/genética , Reacción en Cadena de la Polimerasa/veterinaria , Análisis para Determinación del Sexo/veterinaria , Animales , Proteínas Aviares/genética , Secuencia de Bases , Sondas de ADN , Águilas/fisiología , Femenino , Masculino , Datos de Secuencia Molecular , Reproducibilidad de los Resultados , Alineación de SecuenciaRESUMEN
Transforming growth factor-beta (TGF-beta), Smads, and the cyclin-dependent kinase (cdk) inhibitor p21(WAF1) are important in the pathogenesis of diabetic tubular hypertrophy. Phosphoinositide 3 kinase (PI3K)/Akt kinase activity is increased in diabetic glomerular hypertrophy. Thus, we studied the role of PI3K in high glucose (30 mM)-induced p21(WAF1), Smad2/3, and cell cycle-dependent hypertrophy in LLC-PK1 cells. We found that high glucose time-dependently (1-48 h) increased PI3K/Akt kinase activity. LY294002 (a PI3K inhibitor) attenuated high glucose-induced cell cycle-dependent (G(0)/G(1) phase) hypertrophy at 72 h while attenuating high glucose-induced p21(WAF1) gene transcription and protein expression at 36-48 h. LY294002 also attenuated high glucose-induced binding of p21(WAF1) to the cyclin E/cdk2 complex, whereas attenuating high glucose-induced TGF-beta bioactivity, Smad2/3 phosphorylation, and Smad2/3 DNA-binding activity at 36-48 h. We concluded that PI3K is required for high glucose-induced cell cycle-dependent hypertrophy, p21(WAF1) transcription and expression, p21(WAF1) binding to the cyclin E/cdk2 complex, TGF-beta bioactivity, and Smad2/3 activity in LLC-PK1 cells.
Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina/fisiología , Glucosa/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Animales , Ciclo Celular , Línea Celular , Cromonas/farmacología , Ciclina E/metabolismo , Riñón/fisiología , Morfolinas/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Porcinos , Factor de Crecimiento Transformador beta/efectos de los fármacos , Factor de Crecimiento Transformador beta/fisiologíaRESUMEN
OBJECTIVE: Alpha-fetoprotein (AFP) is not a useful tumor marker for diagnosis of small hepatocellular carcinoma (HCC). There is over-expression of insulin-like growth factor (IGF)-II in HCC tissue. This study investigates the diagnostic application of IGF-II in small HCC. MATERIAL AND METHODS: Serum levels of IGF-II and AFP were determined in 41 patients with small cirrhotic HCC (< or = 3 cm), 41 sex- and age-matched patients with cirrhosis alone (LC), and 41 healthy adults. The optimal cut-off values for diagnosing HCC were determined with receiver operating characteristics (ROC) curve. RESULTS: Both IGF-II and AFP levels in HCC were higher than those in LC patients or controls (each p = 0.0001). The IGF-II levels in LC patients were lower than those in controls (p = 0.001). In HCC patients, multivariate analysis indicated that that both IGF-II (odds ratio, 4.54; 95% confidence interval, 2.15-9.55; p = 0.0001) and AFP (odds ratio, 1.05; 95% confidence interval, 1.01-1.08; p = 0.003) were found to be associated with an increased risk of presence of HCC. The optimal cut-off values of IGF-II (4.1 mg/g prealbumin) and AFP (50 ng/ml) were determined with ROC curves. The sensitivity, specificity, and diagnostic accuracy values for IGF-II were 63%, 90%, and 70%, respectively. Those for AFP were 44%, 95%, and 70%, respectively. Determination of both markers in parallel significantly increase the diagnostic accuracy (88%) and sensitivity (80%), with a high specificity (90%). CONCLUSIONS: Serum IGF-II level can be used as an independent serologic marker or a complementary tumor marker to AFP for diagnosis of small HCC.
Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/sangre , Factor II del Crecimiento Similar a la Insulina/análisis , Cirrosis Hepática/sangre , Neoplasias Hepáticas/sangre , Adulto , Anciano , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Cirrosis Hepática/mortalidad , Cirrosis Hepática/patología , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Probabilidad , Pronóstico , Curva ROC , Valores de Referencia , Medición de Riesgo , Sensibilidad y Especificidad , Análisis de SupervivenciaRESUMEN
To evaluate the diagnostic application of serum insulin-like growth factor-II (IGF-II) and alpha-fetoprotein (AFP) levels in hepatocellular carcinoma (HCC), IGF-II and AFP were determined in 100 cirrhotic patients with HCC, 100 sex- and age-matched patients with cirrhosis alone and 50 healthy controls. The results indicated that IGF-II and AFP levels in patients with HCC were higher than in those with cirrhosis alone (p = 0.0001). There is an inverse correlation between IGF-II and (log)AFP (r = -0.410, p = 0.0001) in patients with HCC. Multivariate analysis indicated that IGF-II and AFP were closely associated, in a dose-related fashion, with the presence of HCC. Receiver operating characteristic curves were used to determine the optimal cutoff values of IGF-II (4.5 mg/g prealbumin) and AFP (100 ng/ml), respectively. Both IGF-II and AFP show a high specificity and positive likelihood ratio. The sensitivity was 42.0% for IGF-II and 73.0% for AFP. Determination of both markers in parallel significantly increased the diagnostic accuracy (96.5%) and sensitivity (97.9%), with a high specificity (95.1%) and positive likelihood ratio (19.9). In conclusion, IGF-II and AFP may be used as complementary tumor markers to discriminate HCC from cirrhosis.
Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/diagnóstico , Factor II del Crecimiento Similar a la Insulina/análisis , Neoplasias Hepáticas/diagnóstico , alfa-Fetoproteínas/análisis , Adulto , Anciano , Carcinoma Hepatocelular/complicaciones , Femenino , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Masculino , Persona de Mediana Edad , Curva ROC , Factores de RiesgoRESUMEN
Recent studies show that up-regulation of cyclooxygenase-2 (COX-2) in human cancer cells induces activation of matrix metalloproteinases (MMPs) and increase of metastatic potential. In this study, we investigate the effect of a COX-2 selective inhibitor, NS398, on the expression and enzymatic activity of MMPs in human lung cancer cells. We found that NS398 inhibited MMP-2, not MMP-9, mRNA expression. NS398 also reduced the amount of MMP-2, not MMP-9, released into the medium. Additionally, this COX-2 inhibitor attenuated the degrading activity of MMP-2 as demonstrated by gelatin zymography. Investigation of cellular MMP-2 by Western blotting indicated that synthesis and processing of MMP-2 was significantly suppressed by NS398. We performed promoter activity assay to address whether NS398 might affect MMP-2 gene transcription. Our results indicated that NS398 directly inhibited MMP-2 promoter activity. However, the inhibitory effect of NS398 is not fully dependent on inhibition of COX-2 because a high concentration of NS398 was needed to suppress MMP-2 expression and addition of prostaglandin E2 only partially reversed the action of NS398. Moreover, a non-selective COX inhibitor indomethacin also suppressed the expression of MMP-2. Taken together, these results indicate that non-steroidal anti-inflammatory drugs suppress MMP-2 expression via repression of transcription and support the notion that COX inhibitors may be useful in inhibition and/or prevention of metastasis.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Neoplasias Pulmonares/enzimología , Metaloproteinasa 2 de la Matriz/genética , Nitrobencenos/farmacología , Sulfonamidas/farmacología , Transcripción Genética/efectos de los fármacos , Medios de Cultivo Condicionados , Inhibidores de la Ciclooxigenasa/farmacología , Dinoprostona/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Regiones Promotoras Genéticas/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Células Tumorales CultivadasRESUMEN
Advanced glycation end products (AGEs) are important in the pathogenesis of diabetic nephropathy, which leads to renal fibrosis. Previously, we found that the janus kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway is necessary for AGE-induced cellular proliferation in normal rat kidney interstitial fibroblast (NRK-49F) cells. However, a direct link between JAK/STAT and cell-cycle progression has not been well established. In this regard, STAT5 has been found to induce cyclin D1 and proliferation in hematopoietic cells. Therefore, we examined effects of AGE on STAT5 and cell-cycle-dependent mitogenesis in NRK-49F cells. We found that AGE increased cyclin D1 expression and cyclin-dependent kinase (cdk)4 activity while decreasing p21(WAF1/CIP1) expression. We also found that AGE (100 microg/mL) induced STAT5 tyrosine phosphorylation. Meanwhile, AGE induced STAT5 protein-DNA binding activity, which was reversed by AG-490 (a specific JAK2 inhibitor) and STAT5 decoy oligodeoxynucleotide (ODN). In addition, STAT5 decoy ODN reversed AGE-induced cell-cycle-dependent cellular proliferation and cyclin D1 protein expression. We concluded that AGE induced cell-cycle-dependent cellular proliferation by inducing the JAK2-STAT5-cyclin D1 and cdk4 pathways in NRK-49F cells.
Asunto(s)
División Celular/efectos de los fármacos , Ciclina D1/efectos de los fármacos , Proteínas de Unión al ADN/fisiología , Productos Finales de Glicación Avanzada/farmacología , Proteínas de la Leche , Proteínas Tirosina Quinasas/fisiología , Proteínas Proto-Oncogénicas , Transactivadores/fisiología , Animales , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , Proteínas de Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/metabolismo , División Celular/fisiología , Línea Celular , Ciclina D1/metabolismo , Quinasa 4 Dependiente de la Ciclina , Quinasas Ciclina-Dependientes/efectos de los fármacos , Quinasas Ciclina-Dependientes/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Ensayo de Cambio de Movilidad Electroforética , Janus Quinasa 2 , Oligonucleótidos/genética , Oligonucleótidos/farmacología , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Factor de Transcripción STAT5 , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Transactivadores/genética , Transactivadores/metabolismo , Tirosina/metabolismoRESUMEN
Morse code is a simple, speedy and low cost means of communication composed of a series of dots, dashes and space intervals. Each tone element (either a dot, dash or space interval) is transmitted by sending a signal for a defined length of time. This poses a challenge as the automatic recognition of Morse code is dependent upon maintaining a stable typing rate. In this paper, a suitable adaptive automatic recognition method, combining the least-mean-square (LMS) algorithm with a neural network, was applied to this problem. The method presented in this paper is divided into five modules: space recognition, tone recognition, learning process, adaptive processing and character recognition. Statistical analyses demonstrated that the proposed method elicited a better recognition rate in comparison with other methods in the literature.
Asunto(s)
Comunicación , Personas con Discapacidad/rehabilitación , Redes Neurales de la Computación , Algoritmos , HumanosRESUMEN
Our previous work has shown that a number of sphingolipid metabolites including sphingosine, sphinganine, and other long-chain bases potently induced apoptosis in human hepatoma cells. In this study, we examined the possibility that sphingosine may trigger apoptosis in human hepatoma cells via inhibition of anti-apoptotic pathways. We investigated the effect of sphingosine on AKT kinase, a serine/threonine kinase which was found to protect cells from apoptosis induced by a variety of extracellular stresses. Our results indicated that sphingosine inhibited basal and serum-stimulated AKT kinase activity in a dose-dependent manner in hepatoma cells. Additionally, sphingosine-induced inhibition of AKT kinase was correlated with induction of apoptosis in these cells. Pretreatment of insulin, a potent stimulator of AKT kinase, partially reversed the inhibition of AKT kinase by sphingosine and counteracted the apoptotic action of this sphingolipid. Expression of activated AKT kinase partially protected cells from sphingosine-induced apoptosis, whereas expression of kinase-dead AKT kinase had no effect. The molecular mechanism by which AKT kinase suppressed the apoptotic action of sphingosine was investigated. Our results showed that increased release of cytochrome C from mitochondria and subsequent activation of caspase-3 were detected in sphingosine-treated hepatoma cells. On the contrary, expression of activated AKT kinase in Hep3B cells attenuated cytochrome C release and caspase-3 activation induced by sphingosine. Taken together, these findings suggest that suppression of AKT kinase is one of the mechanisms by which sphingosine induces apoptosis in hepatoma cells and activation of AKT kinase may inhibit sphingosine-induced apoptosis by blocking a step upstream of cytochrome C release and caspase-3 activation.
Asunto(s)
Apoptosis/fisiología , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas/metabolismo , Esfingosina/toxicidad , Apoptosis/efectos de los fármacos , Proteínas Sanguíneas/farmacología , Grupo Citocromo c/metabolismo , Activación Enzimática/fisiología , Humanos , Ácido Mirístico/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Células Tumorales CultivadasRESUMEN
BACKGROUND/AIMS: Hemodialysis (HD) patients are prone to developing peptic ulcers. However, of all the risk factors associated with peptic ulcers, none have been shown to be more prevalent in HD patients than in the general population. However, salivary epidermal growth factor (EGF) may play a role in peptic ulcer diseases. METHODS: Salivary EGF levels and bioactivities were assayed in 47 maintenance HD patients and 30 normal controls, and the molecular weights of EGF were assessed using high-performance liquid chromatography (HPLC). RESULTS: Salivary EGF levels were not different between both groups of subjects (4.2 +/- 0.34 vs. 5 +/- 0.54 ng/mg protein, NS), and HPLC revealed that salivary EGF in both groups had similar molecular weights. However, salivary EGF bioactivity was significantly depressed in the HD patients as compared to the normal controls (0.59 +/- 0.08 vs. 1.55 +/- 0.15 ng/mg protein, p < 0.01). Stepwise multiple regression showed that the low salivary EGF levels were associated with female gender (p < 0.05), while low salivary EGF bioactivity was associated with HD per se (p < 0.05). In the 22 HD patients who underwent gastric endoscopy, salivary EGF bioactivity was significantly lower in those with peptic ulcers than in those without (0.38 +/- 0.08 vs. 0.69 +/- 0.08 ng/mg protein, p < 0.05). CONCLUSION: Decreased salivary EGF bioactivity may contribute to peptic ulcer disease among maintenance HD patients.
Asunto(s)
Factor de Crecimiento Epidérmico/metabolismo , Úlcera Péptica/etiología , Úlcera Péptica/metabolismo , Diálisis Renal/efectos adversos , Saliva/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
The role of betel quid chewing in the aetiology of hepatocellular carcinoma (HCC) was evaluated in a case-control study including 263 pairs of age- and sex-matched HCC patients and healthy controls. Serum hepatitis B surface antigen (HBsAg), and antibodies to hepatitis C virus (anti-HCV) were determined, and standardized personal interview conducted using a structured questionnaire. Multivariate analysis indicated that betel quid chewing (odds ratio (OR), 3.49; 95% confidence interval (CI), 1.74-6.96), HBsAg (OR, 16.69; 95% CI, 9.92-28.07), anti-HCV (OR, 38.57; 95% CI, 18.15-81.96), and educational duration of less than 10 years (OR, 1.71; 95% CI, 1.05-2.78) are independent risk factors of HCC. In addition, there was an additive interaction between betel quid chewing and chronic infection with either hepatitis B virus (synergy index, 5.37) or hepatitis C virus (synergy index, 1.66). Moreover, risk on HCC increased as duration of betel quid chewing increased, or amount of betel quid consumed (each P for trend < 0.0001).
Asunto(s)
Areca/efectos adversos , Carcinoma Hepatocelular/etiología , Neoplasias Hepáticas/etiología , Plantas Medicinales , Adulto , Anciano , Carcinoma Hepatocelular/epidemiología , Estudios de Casos y Controles , Escolaridad , Femenino , Hepatitis B/diagnóstico , Hepatitis C/diagnóstico , Humanos , Neoplasias Hepáticas/epidemiología , Masculino , Masticación , Persona de Mediana Edad , Factores de RiesgoRESUMEN
Advanced glycation end-product (AGE) is important in the pathogenesis of diabetic nephropathy (DN), and captopril (an angiotensin converting enzyme inhibitor) is effective in treating this disorder. We have shown that the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) cascade is responsible for AGE-induced mitogenesis in NRK-49F (normal rat kidney fibroblast) cells, but its role in renal fibrosis in DN remains unknown. Therefore, we have sought to determine whether JAK/STAT is involved in AGE-regulated collagen production in NRK-49F cells. We found that AGE time (1-7 days) and dose (10-200 microg/ml)-dependently increased collagen production in these cells. Additionally, AGE increased RAGE (receptor for AGE) protein expression. AGE-induced RAGE expression was dose-dependently inhibited by antisense RAGE oligodeoxynucleotide (ODN) and captopril. AGE-induced type I collagen production and JAK2-STAT1/STAT3 activation were decreased by AG-490 (a specific JAK2 inhibitor), antisense RAGE ODN and captopril. Meanwhile, STAT1 and STAT3 decoy ODNs also suppressed the induction of collagen by AGE. We concluded that RAGE and the JAK2-STAT1/STAT3 pathway were involved in AGE-induced collagen production in NRK-49F cells. Furthermore, captopril was found to reverse AGE-induced collagen production, probably by attenuating RAGE expression and JAK2-STAT1/STAT3 activities.
Asunto(s)
Colágeno/biosíntesis , Proteínas de Unión al ADN/metabolismo , Productos Finales de Glicación Avanzada , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas , Receptores Inmunológicos/metabolismo , Transducción de Señal , Transactivadores/metabolismo , Secuencia de Bases , Captopril/farmacología , Línea Celular , Cartilla de ADN , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Janus Quinasa 2 , Cinética , Oligonucleótidos Antisentido/farmacología , Fosforilación , Receptor para Productos Finales de Glicación Avanzada , Receptores Inmunológicos/genética , Factor de Transcripción STAT1 , Factor de Transcripción STAT3 , Tirosina/metabolismo , Tirfostinos/farmacologíaRESUMEN
Increased expression of cyclooxygenase-2 (COX-2) causes enhanced production of prostaglandins, which are emerging as important mediators of growth stimulation of cancer cells. Overexpression of COX-2 has been found in human non-small cell lung cancer tissues and cell lines. In vitro and in vivo studies showed that nonselective cyclooxygenase inhibitors (like aspirin and indomethacin) may suppress growth of lung cancer cells and may prevent lung tumorigenesis induced by the tobacco-specific carcinogens. However, the molecular mechanisms that mediated the anticancer action of these inhibitors are not well defined. In this study, we examined the effect of a specific COX-2 inhibitor, N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide (NS398), on high COX-2-expressing A549 lung cancer cells. Our results indicated that NS398 inhibited prostaglandin E(2) synthesis and induced G(1) growth arrest in these cells. NS398 specifically up-regulated cyclin-dependent kinase inhibitor p27(KIP1), whereas the expressions of G(1)-acting cyclins and cyclin-dependent kinases were not changed. Additionally, NS398 effectively suppressed cyclin E-associated kinase activity in A549 cells. The molecular mechanism responsible for the induction of p27(KIP1) by NS398 was characterized. We found that NS398 did not induce p27(KIP1) through transcriptional activation because this drug could not stimulate the p27(KIP1) promoter. Metabolic labeling experiments showed that the synthesis rate of p27(KIP1) protein was not altered by NS398. Conversely, pulse-chase assays demonstrated that degradation of p27(KIP1) protein was obviously reduced in NS398-treated cells. We conclude that NS398 enhances p27(KIP1) expression via post-translational regulation, and our results provide a new mechanism by which specific COX-2 inhibitors suppress proliferation of cancer cells.
Asunto(s)
Antineoplásicos/farmacología , Proteínas de Ciclo Celular , Fase G1/efectos de los fármacos , Proteínas Asociadas a Microtúbulos/biosíntesis , Nitrobencenos/farmacología , Sulfonamidas/farmacología , Proteínas Supresoras de Tumor , División Celular/efectos de los fármacos , Ciclina G , Ciclina G1 , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/farmacología , Dinoprostona/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/biosíntesis , Neoplasias Pulmonares , Proteínas de la Membrana , Proteínas Asociadas a Microtúbulos/genética , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Biosíntesis de Proteínas/efectos de los fármacos , Células Tumorales Cultivadas , Regulación hacia ArribaRESUMEN
This study aimed to investigate sex differences in relation to hepatitis B e antigen (HBeAg) and serum alanine aminotransferase (ALT) levels in chronic asymptomatic hepatitis B virus (HBV) infection. HBeAg and ALT level were determined in 636 asymptomatic hepatitis B surface antigen carriers. There was no significant sex differences in the age-adjusted prevalence of HBeAg. Abnormal ALT level (>45 IU/l) was more frequent in carriers with HBeAg (17.5% vs 7.6%; P = 0.001). Multivariate analysis indicated that male sex (odds ratio, 2.0; 95% confidence interval, 1.1-3.6) and HBeAg (odds ratio, 2.6; 95% confidence interval, 1.6-4.3) were independent risk factors for abnormal ALT levels. Male sex and HBeAg-positivity are independent risk factors for abnormal ALT activity in chronic HBV infection. This observation may be related to sex differences in chronic HBV infection.
Asunto(s)
Alanina Transaminasa/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/inmunología , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Hepatitis B Crónica/sangre , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Factores de Riesgo , Caracteres SexualesRESUMEN
Our previous results demonstrated that the plant amino acid mimosine blocked cell cycle progression and suppressed proliferation of human lung cancer cells in vitro by multiple mechanisms. Inhibition of cyclin D1 expression or induction of cyclin-dependent kinase inhibitor p21WAF1 expression was found in mimosine-treated lung cancer cells. However, whether mimosine may modulate the expression of these cell cycle regulatory proteins and suppress tumor growth in vivo is unknown. In this study, we examined the anti-cancer effect of mimosine on human H226 lung cancer cells grown in nude mice. Our results demonstrated that mimosine inhibits cyclin D1 and induces p21WAF1 expression in vivo. Furthermore, results of TUNEL analysis indicated that mimosine may induce apoptosis to suppress tumor growth in nude mice. Collectively, these results suggest that mimosine exerts anti-cancer effect in vivo and might be useful in the therapy of lung cancer.
Asunto(s)
Proteínas de Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Mimosina/farmacología , Neoplasias Experimentales/prevención & control , Animales , Apoptosis/efectos de los fármacos , Proteínas de Ciclo Celular/biosíntesis , Ciclina D1/biosíntesis , Ciclina D1/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/biosíntesis , Ciclinas/efectos de los fármacos , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Factores de Tiempo , Trasplante Heterólogo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
We aimed to assess the diagnostic application of urinary epidermal growth factor receptor (EGFR)-binding growth factors in cancers of the digestive tract. By radioreceptor assay and radioimmunoassay, we determined these growth factors in 115 patients with various cancers of the digestive tract, 30 patients with benign disease, and 40 healthy controls. The receiver operating characteristic (ROC) curve and likelihood ratio were employed to determine the best diagnostic efficiency. Urinary EGFR-binding growth factors in each cancer group were significantly higher than those in the non-cancer groups. Multivariate analysis indicated that the growth factors, determined by both the radioreceptor assay (odds ratio, 1.184; 95% confidence interval,1.077-1.302; P = 0.001) and radioimmunoassay (odds ratio,1.055; 95% confidence interval, 1.002-1.111; P = 0.039), were associated, in a dose-related fashion, with the presence of cancers. By ROC curve analysis, the optimal cutoff values for EGFR-binding growth factors were 25.5 microg/g creatinine (radioreceptor assay) and 33.6 microg/g creatinine (radioimmunoassay). The resulting sensitivity, specificity, diagnostic accuracy, and positive and negative likelihood ratios were 84.4%. 87.5%, 85.2%, 6.75 and 0.18 (for radioreceptor assay) and 86.1%, 67.5%, 81.3%, 2.64 and 0.21 (for radioimmunoassay), respectively. Except for pancreatic cancer the growth factors showed moderate diagnostic efficiency for the other digestive tract cancers. In conclusion, urinary EGFR-binding growth factors were increased in cancers of the digestive tract. They may be used as diagnostic tumor markers.
Asunto(s)
Biomarcadores de Tumor/orina , Neoplasias del Sistema Digestivo/orina , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Endopeptidasas/metabolismo , Femenino , Sustancias de Crecimiento/metabolismo , Humanos , Ligandos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Curva ROC , Radioinmunoensayo , Ensayo de Unión Radioligante , Análisis de Regresión , Sensibilidad y EspecificidadRESUMEN
Although originally synthesized as an anti-estrogen, tamoxifen (Tam) was found to be able to inhibit proliferation of estrogen receptor (ER)-negative cancer cells in vitro. However, the molecular basis of such ER-independent growth inhibition is largely unknown. We have previously demonstrated that Tam induces p21WAF1 and p27KIP1 expression in human lung cancer cells which lack ER-alpha and -beta. We found that Tam induced p21WAF1 expression via transcriptional activation. In order to determine the molecular mechanism responsible for p21WAF1 induction by Tam, we performed a deletion analysis on the p21WAF1 promoter. The minimal region in the p21WAF1 promoter required for Tam-activated induction was mapped to a contiguous stretch of 10 bp located 83 bases upstream of the transcription initiation site. Our results showed that transcription factor Sp1 and Sp3 bound to this GC-rich region and mutation of Sp1-binding sites dramatically attenuated Tam-induced p21WAF1 promoter activity. We also tried to elucidate the signaling pathway that mediated the activation of p21WAF1 by Tam. Inhibition of mitogen-activated protein kinase pathways did not block Tam-induced p21WAF1. Similarly, protein kinase C inhibitor calphostin C could not suppress Tam-induced p21WAF1. Conversely, pretreatment of a specific protein kinase A inhibitor H89 significantly attenuated the induction of p21WAF1 by Tam. Furthermore, PKA activators forskolin and dibutyryl-cAMP activated p21WAFI promoter activity and increased p21wAF1 protein level in lung cancer cells. Taken together, these results demonstrate that Tam activates the p21WAF1 promoter via Sp1-binding sites and suggest that PKA may be involved in the induction of p21wAF1 by Tam in ER-negative lung cancer cells.
Asunto(s)
Antineoplásicos Hormonales/farmacología , Ciclinas/genética , Antagonistas de Estrógenos/farmacología , Regiones Promotoras Genéticas , Receptores de Estrógenos/metabolismo , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Factor de Transcripción Sp1/metabolismo , Tamoxifeno/farmacología , Antineoplásicos Hormonales/metabolismo , Sitios de Unión , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Proteínas de Unión al ADN/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Luciferasas/genética , Luciferasas/metabolismo , Neoplasias Pulmonares , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Mutagénesis , Proteínas Nucleares/metabolismo , Proteína Quinasa C/antagonistas & inhibidores , Elementos de Respuesta , Moduladores Selectivos de los Receptores de Estrógeno/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Transcripción Sp1/genética , Factor de Transcripción Sp3 , Factores de Transcripción/metabolismo , Células Tumorales CultivadasRESUMEN
The plant amino acid mimosine has been reported to block cell cycle progression in the late G1 phase. A recent study showed that mimosine might induce growth arrest by activating the expression of p21CIP1, a cyclin-dependent kinase inhibitor (CDKI), and by inhibiting the activity of cyclin E-associated kinases in human breast cancer cells. However, mimosine at higher concentrations also blocked proliferation of p21-/- cells by unknown mechanisms. In this study, we investigated the effect of mimosine on the expression of cyclins and CDKIs in human lung cancer cells. We found that mimosine specifically inhibited cyclin D1 expression in H226 cells. The expression of another G1 cyclin, cyclin E, was not regulated by mimosine in all lung cancer cell lines examined. Moreover, mimosine induced p21CIP1 expression in H226 and H358 cells, while it activated p27KIP1 expression in H322 cells. However, mimosine does not affect transcription of these genes directly because significant changes in cyclin D1 or CDKI expression were observed at 12-24 h after drug addition. Our results indicate that mimosine may block cell proliferation by multiple mechanisms and this amino acid is a useful agent for the study of cell cycle control.
Asunto(s)
Ciclinas/biosíntesis , Inhibidores Enzimáticos/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Mimosina/uso terapéutico , Proteínas de Neoplasias/biosíntesis , División Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Fase G1/efectos de los fármacos , Humanos , Neoplasias Pulmonares/patología , Células Tumorales CultivadasRESUMEN
It has been reported that nonsteroidal anti-inflammatory drugs (NSAIDs) suppress bone repair and bone remodeling but only mildly inhibit bone mineralization at the earlier stage of the repair process. We proposed that the proliferation and/or the earlier stage of differentiation of osteoblasts may be affected by NSAIDs. This study was designed to investigate whether NSAIDs affect the proliferation and/or differentiation of osteoblasts and whether these effects are prostaglandin (PG) mediated. The effects of PGE1 and PGE2, indomethacin, and ketorolac on thymidine incorporation, cell count, intracellular alkaline phosphatase (ALP) activity, and Type I collagen content in osteoblast-enriched cultures derived from fetal calvaria were evaluated. The results showed that both PGs and NSAIDs inhibited DNA synthesis and cell mitosis in a time- and concentration-dependent manner. However, intracellular ALP activity and Type I collagen content were stimulated at an earlier stage of differentiation in osteoblasts. These results suggested that (i) the inhibitory effect of ketorolac on osteoblastic proliferation contributes to its suppressive effects on bone repair and remodeling in vivo; (ii) PGEs and NSAIDs may be involved in matrix maturation and biologic bone mineralization in the earlier stage of osteoblast differentiation; and (iii) the effects of ketorolac and indomethacin on cell proliferation and differentiation may not be through the inhibition of the synthesis of PGE1 or PGE2.
Asunto(s)
Alprostadil/farmacología , Antiinflamatorios no Esteroideos/farmacología , Dinoprostona/farmacología , Osteoblastos/efectos de los fármacos , Fosfatasa Alcalina/metabolismo , Animales , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Células Cultivadas , Colágeno/metabolismo , Replicación del ADN/efectos de los fármacos , Mitosis/efectos de los fármacos , Osteoblastos/enzimología , Osteoblastos/patología , Ratas , Ratas Sprague-DawleyRESUMEN
Tamoxifen (Tam), besides its action as an anti-estrogen, also inhibits cell proliferation of estrogen receptor (ER)-negative cancer cells by an unknown mechanism. In this study, we used ER-negative lung cancer cells to clarify such ER-independent inhibitory effect of Tam. We found that Tam induced G1 growth arrest in these cells. However, our results indicated that the expression of G1 cyclins (including D1, 2, 3 and E) was not regulated by Tam in these lung cancer cells. Additionally, the protein levels of G1 acting cyclin-dependent kinases (CDKs), CDK2, 4 and 6, was unaltered in Tam-treated lung cancer cells with the exception of CDK2 expression in H322 cells which was attenuated by Tam in a cell line-specific manner. We next examined the effect of Tam on the expression of cyclin-dependent kinase inhibitors (CDKIs) and our results demonstrated that the expression of p21WAF1 and p27KIP1, but not p57KIP2, was strongly activated by Tam in these cells. The amounts of p21WAF1 and p27KIP1 co-immunoprecipitated with cyclin E were obviously increased after Tam treatment and reduced activity of cyclin E-associated kinases and accumulation of hypo-phosphorylated retinoblastoma (Rb) protein were clearly detected in Tam-incubated cells. No consentaneous induction of CDKIs was found when ER-negative lung cancer cells were incubated with cytotoxic drugs, cisplatin and etoposide, this indicates that enhancement of CDKI expression is not a non-specific effect of Tam. We also found that Tam may up-regulate p21WAF1 expression via transcription activation. Considered together, these results suggest that Tam-induced growth inhibition in ER-negative lung cancer cells is associated with induction of p21WAF1 and p27KIP1.