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2.
Support Care Cancer ; 24(1): 157-161, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25962615

RESUMEN

PURPOSE: Adverse oral symptoms gradually appear in advanced cancer patients as the disease progresses. We retrospectively investigated the associations between the incidence of oral problems and the days to death (DTD) in patients receiving palliative care. METHODS: The dental assessment sheets and medical charts of 105 patients who had been admitted into the palliative care unit at our hospital were examined. Case data included evaluations of organic and functional oral conditions at the time of admission for all patients. The cohort was divided into two groups according to the DTD as the short group (<28 days from the time of dental assessment until death) and the long group (≥28 days). We compared the incidences of organic and functional oral problems between these groups. RESULTS: Dry mouth, tongue inflammation, and bleeding spots were significantly more frequent in the short group than in the long group (78 vs. 54% for dry mouth, 67 vs. 46% for tongue inflammation, 35 vs. 14% for bleeding spots, respectively; p < 0.05). Tongue coating and candidiasis were comparable between the two groups. Dysphagia was significantly more common in the short group (43%) than in the long group (20%) (p = 0.01), as was assistance with oral health care (76 vs. 50%) (p = 0.01). CONCLUSIONS: Our findings suggest that, during palliative care, oral complications appear more frequently when the DTD period is shorter. These symptoms may be useful indicators when deciding on the proper timing of intensive oral care intervention to decrease oral problems and pain in terminally ill patients.


Asunto(s)
Enfermedades de la Boca/mortalidad , Neoplasias/complicaciones , Cuidados Paliativos/métodos , Cuidados Críticos , Muerte , Femenino , Humanos , Masculino , Enfermedades de la Boca/complicaciones , Salud Bucal , Estudios Retrospectivos
4.
Transplant Proc ; 45(4): 1476-80, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23726601

RESUMEN

We examined the efficacy and safety of 4-drug combination therapy using high-dose mizoribine (MZR) (8 mg/kg/d), cyclosporine (CsA), basiliximab (BXM), and steroid (STR) in 39 renal transplant recipients. Acute rejection episodes (ARE), which occurred in 9 (23.1%) patients, correlated with lower blood levels of MZR (trough levels ≥ 2 µg/mL). In addition, lower MZR concentrations tended to be associated with a higher incidence of rejection episodes in children aged ≤ 10 years than in those aged ≥ 11 years. The area under the received operating characteristics (ROC) curve of MZR trough level to pred ARE was 0.825 (95% confidence interval, 0.690-0.962; P = .002). Based on the ROC analysis, are MZR cut-off of 1.6 µg/mL showed a sensitivity of 81.8% and a specificity of 75.0%. Adverse events were observed in 23 patients, including infections in 11 (7 patients positive for cytomegalovirus [CMV] antigen and 4 treated with anti-CMV drugs). The MZR trough levels seemed to be higher among patients with adverse events than in those free of them, but it was no significant. All patients experienced successful engraftment except 1 who died of unknown cause with a functioning graft. In conclusion, our study showed that low MZR trough levels correlated with the incidence of ARE. No serious adverse effects were encountered with this therapy.


Asunto(s)
Corticoesteroides/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Ciclosporina/administración & dosificación , Inmunosupresores/administración & dosificación , Trasplante de Riñón , Proteínas Recombinantes de Fusión/administración & dosificación , Ribonucleósidos/administración & dosificación , Adolescente , Adulto , Anciano , Basiliximab , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Adulto Joven
5.
Diabetes Obes Metab ; 15(9): 833-43, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23565760

RESUMEN

AIMS: To evaluate the long-term safety and efficacy of linagliptin as add-on therapy to one approved oral antidiabetic drug (OAD) in Japanese patients with type 2 diabetes mellitus and insufficient glycaemic control. METHODS: This 52-week, multicentre, open-label, parallel-group study evaluated once-daily linagliptin 5 mg as add-on therapy to one OAD [biguanide, glinide, glitazone, sulphonylurea (SU) or α-glucosidase inhibitors (A-GI)] in 618 patients. After a 2-week run-in, patients on SU or A-GI were randomized to either linagliptin (once daily, 5 mg) or metformin (twice or thrice daily, up to 2250 mg/day) as add-on therapy. Patients receiving the other OADs received linagliptin add-on therapy (non-randomized). RESULTS: Adverse events were mostly mild or moderate, and rates were similar across all groups. Hypoglycaemic events were rare, except in the SU group. Overall, 26 (5.8%) hypoglycaemic events were reported in patients receiving linagliptin (non-randomized). Hypoglycaemic events were similar for linagliptin and metformin added to A-GI (1/61 vs. 2/61, respectively) or SU (17/124 vs. 10/63, respectively). Significant reductions in glycated haemoglobin (HbA1c) levels (between -0.7 and -0.9%) occurred throughout the study period for the background therapy groups that received linagliptin (baseline HbA1c 7.9-8.1%). The decline in HbA1c levels was indistinguishable between linagliptin and metformin groups when administered as add-on therapy to A-GI or SU. CONCLUSIONS: Once-daily linagliptin showed safety and tolerability over 1 year and provided effective add-on therapy leading to significant HbA1c reductions, similar to metformin, over 52 weeks in Japanese patients.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Metformina/administración & dosificación , Purinas/administración & dosificación , Quinazolinas/administración & dosificación , Pueblo Asiatico/estadística & datos numéricos , Biguanidas/administración & dosificación , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Quimioterapia Combinada , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Japón/epidemiología , Linagliptina , Masculino , Persona de Mediana Edad , Compuestos de Sulfonilurea/administración & dosificación , Tiazolidinedionas/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento
6.
Placenta ; 33(2): 106-13, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22118869

RESUMEN

Fetal fibroblast cell culture from cotyledons of bovine placenta and animal experiments close to term were used to elucidate afterbirth release and factors missing in the signal transduction mechanism for retained fetal membranes (RFM) after delivery. In cell culture the addition of arachidonic acid (Ara) to the medium caused rapid release to free floating cell in the culture dish, accompanied by matrix metalloproteinase (MMP) activation, being consistent with previous in vivo observations, where a relation between MMP and fetal membrane release had been shown. Ara-induced cell floating was not inhibited by the addition of cyclooxygenase (COX) inhibitor, and not induced by the addition of PGF2α or PGE2 to replace Ara, while 12-lipoxygenase (12-LOX) metabolite of Ara, 12-oxo-eicosatetraenoic acid (12-oxoETE), strongly induced cell floating. In the animal experiments, 12-oxoETE injection to delivery-induced cows (n = 6) using prostaglandin (PG) and dexamethazone resulted in rapid release of fetal membranes. In cows with natural calf delivery, a 12-oxoETE peak (11.7-16.8 ng/ml) was observed in maternal blood plasma prior to release of fetal membranes. This investigation thus gives new indications for that the mediator for fetal membrane release is 12-oxoETE and not PG.


Asunto(s)
Ácidos Araquidónicos/farmacología , Membranas Extraembrionarias/efectos de los fármacos , Retención de la Placenta/veterinaria , Animales , Araquidonato 12-Lipooxigenasa/metabolismo , Bovinos , Células Cultivadas , Dexametasona/farmacología , Membranas Extraembrionarias/metabolismo , Femenino , Retención de la Placenta/metabolismo , Embarazo , Prostaglandinas/farmacología
7.
J Dairy Sci ; 93(10): 4850-4, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20855019

RESUMEN

Sialic acid, which is located at the terminal end of glycoconjugates, is believed to have important biological functions. Its concentration in bovine milk varies depending on lactation stage and season. However, it remains unclear whether dietary factors, especially fresh forage, affect the total sialic acid concentration in milk. The purpose of the present study was to investigate the effect of grazing on the concentrations of total sialic acid and hexose in bovine milk. Six healthy dairy cows were used in a crossover design (3 cows fed fresh forage and 3 cows fed grass silage) for 2 wk. Individual milk samples were collected at 2 consecutive milkings (morning and evening) at 0, 1, 3, 5, 8, 11, and 14 d of the experimental period, and 2 consecutive samples in each cow were combined on each sampling day in proportion of the morning and evening milk yields. No differences in body weight, milk yield, or milk composition were observed between the 2 groups during the experimental period. The hexose concentration in milk did not differ between these groups during the experimental period. Conversely, the total sialic acid concentration in the milk of each grazing cow significantly increased at 11 and 14 d of the experimental period compared with that at 0 d. In the grass silage group, the total sialic acid concentration at the end of the experimental period tended to be lower than that at 0 d, but the decrease was not significant. These results indicate that grazing management could have increased the concentration of sialoglycoconjugates in milk. This suggests that grazing may increase the biological function of milk because it is thought that sialic acid is significant in many ways.


Asunto(s)
Bovinos/fisiología , Dieta/veterinaria , Hexosas/análisis , Leche/química , Ácido N-Acetilneuramínico/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Estudios Cruzados , Femenino , Poaceae/metabolismo , Ensilaje
8.
Mucosal Immunol ; 3(5): 443-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20505662

RESUMEN

Regulatory T cells (Treg) express the forkhead box p3 (Foxp3) transcription factor and suppress pathological immune responses against self and foreign antigens, including commensal microorganisms. Foxp3 has been proposed as a master key regulator for Treg, required for their differentiation, maintenance, and suppressive functions. Two types of Treg have been defined. Natural Treg (nTreg) are usually considered to be a separate sublineage arising during thymus differentiation. Induced Treg (iTreg) originate upon T cell receptor (TCR) stimulation in the presence of tumor growth factor beta. Although under homeostatic conditions most Treg in the periphery are nTreg, special immune challenges in the intestine promote more frequently the generation of iTreg. Furthermore, recent observations have challenged the notion that Treg are a stable sublineage, and they suggest that, particularly under lymphopenic and/or inflammatory conditions, Treg may lose Foxp3 and/or acquire diverse effector functions, especially in the intestine, which may contribute to uncontrolled inflammation.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Mucosa Intestinal/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Diferenciación Celular , Linaje de la Célula , Epigénesis Genética , Retroalimentación Fisiológica , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/inmunología , Regulación de la Expresión Génica/inmunología , Homeostasis , Humanos , Tolerancia Inmunológica , Inmunidad Mucosa , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/inmunología , Regiones no Traducidas/genética
9.
J Periodontal Res ; 43(4): 386-90, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18221296

RESUMEN

BACKGROUND AND OBJECTIVE: Short-chain fatty acids, such as butyric acid, are detected in periodontal pockets and are thought to be involved in the initiation and progression of periodontal disease. In the present study, we examined the effects of butyric acid on adhesion molecule expression by human gingival epithelial cells. MATERIAL AND METHODS: The human gingival carcinoma cell line, Ca9-22, was cultured in media that contained different concentrations of butyric acid. RESULTS: Cell numbers were significantly decreased in a dose-dependent manner by butyric acid at concentrations of > or = 0.2 mM. The expression of intercellular adhesion molecule-1 mRNA was significantly increased 6 h after stimulation. By contrast, the expression levels of integrins alpha 6 and beta 4 were decreased. Similar results were obtained by flow cytometry. CONCLUSION: The results of the present study indicate that butyric acid alters the expression of adhesion molecules by Ca9-22 cells. The elucidation of the mechanism of action of butyric acid on the periodontium may help to clarify several aspects of the onset and progression of periodontal disease.


Asunto(s)
Ácido Butírico/farmacología , Moléculas de Adhesión Celular/efectos de los fármacos , Encía/efectos de los fármacos , Ácido Butírico/administración & dosificación , Recuento de Células , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Citometría de Flujo , Encía/patología , Humanos , Integrina alfa6/efectos de los fármacos , Integrina beta4/efectos de los fármacos , Molécula 1 de Adhesión Intercelular/efectos de los fármacos , Microscopía Electrónica de Rastreo , Reacción en Cadena de la Polimerasa , Factores de Tiempo
10.
J Dairy Sci ; 90(12): 5665-70, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18024758

RESUMEN

The objective of this study was to show a new function of Se in IgG absorption from colostrum by newborn calves. The same amount and quality of colostrum with or without Se addition was fed to paired calves (n = 60) 4 times at <2, 12, 24, and 36 h after birth, respectively. Four-time feeding of colostrum containing 1.0 ppm Se significantly increased IgG amount in the blood plasma of calves 24 h after birth; however, its effect was small (about 20% increase). Although the addition of 3.0 ppm Se once at the first colostrum feeding was more effective on IgG absorption, its significant effect was a 42% increase on average. The increased IgG concentration of blood plasma continued for about 2 wk. It is known that the absorption of colostrum IgG is mediated by intestinal pinocytosis, which continues for only 24 h after birth. The addition of Se to colostrum might directly activate this physiological pinocytosis of intestinal epithelial cells because of the rapidity of the reaction. This effect is not nutritional but rather pharmacological. Supplemented Se also resulted in its increased concentration in blood plasma. Selenium is an essential mineral for animals; however, newborn calves are always deficient in Se at birth. Application of this method in calves would also provide an immediate supply of Se and might contribute to the development of the immune system of calves. This study showed that Se supplementation to colostrum increased IgG amount and Se concentration in blood plasma in newborn calves.


Asunto(s)
Bovinos/inmunología , Calostro/química , Inmunidad Materno-Adquirida , Inmunoglobulina G/sangre , Pinocitosis/efectos de los fármacos , Selenio/farmacología , Alimentación Animal , Animales , Animales Recién Nacidos/inmunología , Calostro/inmunología , Relación Dosis-Respuesta a Droga , Femenino , Absorción Intestinal/efectos de los fármacos , Pinocitosis/fisiología , Selenio/sangre
11.
Proc Biol Sci ; 274(1626): 2723-9, 2007 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-17711842

RESUMEN

Male fiddler crabs (genus Uca) have an enlarged major claw that is used during fights. In most species, 50% of males have a major claw on the left and 50% on the right. In Uca vocans vomeris, however, less than 1.4% of males are left-clawed. Fights between opponents with claws on the same or opposite side result in different physical alignment of claws, which affects fighting tactics. Left-clawed males mainly fight opposite-clawed opponents, so we predicted that they would be better fighters due to their relatively greater experience in fighting opposite-clawed opponents. We found, however, that (i) a left-clawed male retains a burrow for a significantly shorter period than a size-matched right-clawed male, (ii) when experimentally displaced from their burrow, there is no difference in the tactics used by left- and right-clawed males to obtain a new burrow; however, right-clawed males are significantly more likely to initiate fights with resident males, and (iii) right-clawed residents engage in significantly more fights than left-clawed residents. It appears that left-clawed males are actually less likely to fight, and when they do fight they are less likely to win, than right-clawed males. The low-level persistence of left-clawed males is therefore unlikely to involve a frequency-dependent advantage associated with fighting experience.


Asunto(s)
Braquiuros/fisiología , Lateralidad Funcional/fisiología , Agresión , Animales , Conducta Animal/fisiología , Masculino , Reproducción , Predominio Social
12.
J Dairy Sci ; 89(3): 1043-51, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16507700

RESUMEN

To increase ruminal outflow of trans-vaccenic acid (t-VA), a new strain of Butyrivibrio fibrisolvens (MDT-10) was isolated that has a great ability to hydrogenate linoleic acid (LA) to t-VA. When strain MDT-10 was added to the batch cultures of mixed ruminal microbes (1% of the total number of viable ruminal bacteria), LA conversion to t-VA increased greatly; after 3 h, t-VA levels were > 4-fold higher than the control. By 10 h, all of the t-VA was hydrogenated to stearic acid. However, when a new strain of Bifidobacterium adolescentis (HF-11), which has a high capacity for incorporation of t-VA, was added in conjunction with MDT-10 (1% of the total number of ruminal bacteria), t-VA levels after 10 h were 6 times higher than with MDT-10 alone. These results suggest that t-VA produced by MDT-10 was incorporated into HF-11 cells, resulting in protection of t-VA from t-VA-hydrogenating microbes. Similar results were obtained in a continuous culture of mixed ruminal microbes in which addition of HF-11 simultaneously with MDT-10 increased the amount of t-VA in the effluent 2.5-fold. Both MDT-10 and HF-11 appeared to grow readily in the presence of mixed ruminal microbes. Sixty-two percent of t-VA incorporated by HF-11 was present in the free form, whereas 19, 15, and 3%, respectively, were incorporated into monoacylglycerol, glycerophospholipid, and diacylglycerol fractions. Because these lipids can be digested in the small intestine, it is likely that most t-VA in HF-11 cells is absorbed. Thus, introduction of MDT-10 and HF-11 simultaneously to the rumen might increase the amount of t-VA absorbed and might consequently increase the conversion of t-VA to conjugated linoleic acid in tissue.


Asunto(s)
Ácidos Oléicos/biosíntesis , Ácidos Oléicos/metabolismo , Rumen/microbiología , Animales , Bifidobacterium/metabolismo , Butyrivibrio/aislamiento & purificación , Butyrivibrio/metabolismo , Ácidos Carboxílicos/análisis , Escherichia coli/metabolismo , Ácidos Grasos/análisis , Heces/microbiología , Cabras , Humanos , Hidrogenación , Lactobacillus/metabolismo , Ácido Linoleico/metabolismo , Ácidos Esteáricos/metabolismo
13.
Acta Neurol Scand ; 113(4): 256-61, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16542165

RESUMEN

OBJECTIVES: Stress is involved in the development of symptoms of Meniere's disease (MD). Stress-related disease has been reported to be associated with disorders in the circadian rhythm of melatonin (MEL) which regulates that rhythm. We therefore investigated MEL circadian rhythm of patients with MD. PATIENTS AND METHODS: A comparison of 13 MD patients was made with age-matched controls. Saliva samples were collected every 3 h. A statistical analysis of the circadian rhythm of saliva MEL was performed for a circadian rhythm by the fit of a 24- and 12-h composite cosine model. In addition, we assessed the stress and depression status of the two groups. RESULTS: The rhythmic amplitude of MEL in the MD group was significantly lower than that in the control group (P < 0.05). The acrophase in the MD group was significantly earlier than that in the control group (P < 0.05). MD patients had significantly higher stress score and depression score than control subjects (P < 0.05). The amplitude in MD patients had no significant correlation with their otologic clinical data. CONCLUSIONS: These results suggest that MD patients have a MEL deficiency, which is related to their stress and depression status rather than the otologic pathological status of MD.


Asunto(s)
Ritmo Circadiano/fisiología , Melatonina/metabolismo , Enfermedad de Meniere/metabolismo , Saliva/metabolismo , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Enfermedad de Meniere/psicología , Persona de Mediana Edad , Sueño/fisiología , Estrés Psicológico/complicaciones , Estrés Psicológico/metabolismo
14.
J Appl Microbiol ; 100(4): 787-94, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16553734

RESUMEN

AIM: Isolation of a new strain of Butyrivibrio fibrisolvens possessing great capacity to produce conjugated linoleic acid (CLA) in order to utilize as a probiotic for animals. METHODS AND RESULTS: A novel strain (MDT-5) was isolated from the goat rumen, which exclusively converted linoleic acid (LA) to CLA, because of its high LA isomerase activity with virtually no CLA reductase activity. MDT-5 also converted linolenic acid to conjugated linolenic acid that may be more bioactive than CLA. The oral administration of MDT-5 every other day to mice for 2 weeks resulted in increased amounts of CLA in the contents of the large intestine (2.5-fold), as well as in adipose tissue (threefold). Feeding a high-LA diet, as well as prolonging the period of MDT-5 administration, further increased the CLA content in body fat. CONCLUSIONS: MDT-5 has by far greater ability to produce CLA than any other known bacteria. Administration of MDT-5 to mice increases CLA production in the large intestine, which results in increased CLA absorption. SIGNIFICANCE AND IMPACT OF THE STUDY: MDT-5 may be useful in pet animals as a probiotic to provide CLA continuously.


Asunto(s)
Butyrivibrio/aislamiento & purificación , Ácidos Linoleicos/metabolismo , Probióticos/administración & dosificación , Tejido Adiposo/metabolismo , Administración Oral , Animales , Dieta , Cabras , Intestino Grueso/metabolismo , Isomerismo , Ácido Linoleico/administración & dosificación , Ácido Linoleico/metabolismo , Ácidos Linoleicos Conjugados/análisis , Ácidos Linoleicos Conjugados/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Rumen/microbiología
15.
Transplant Proc ; 37(4): 1762-3, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15919457

RESUMEN

BACKGROUND: Acute rejection is a major problem in kidney transplantation. To reduce its likelihood, we investigated the efficacy and safety of an immunosuppressive regimen including tacrolimus, basiliximab, mycophenolate mofetil, and low-dose steroids. METHODS: Fifty-seven patients, including 14 pediatric patients, were enrolled in this study. The mean age at the time of transplantation was 33.5 years, and the mean observation period was 8.2 months. The mean trough concentrations of FK at 1, 6, and 12 months posttransplant were 10.2, 6.6, and 6.0 ng/mL, respectively. RESULTS: All recipients survived without graft loss. The cumulative incidence of acute rejection in adults was 2.3% and 8.4% at 6 and 12 months posttransplant, respectively. Of the adverse events, 11 recipients (19.3%) were positive for CMV antigenemia or had CMV infections. Four recipients (7.0%) exhibited mild hyperglycemia. CONCLUSIONS: Our immunosuppressive regimen demonstrated favorable results, reducing the incidence of acute rejection without causing severe adverse events, especially in adults.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Rechazo de Injerto/prevención & control , Ácido Micofenólico/análogos & derivados , Proteínas Recombinantes de Fusión/uso terapéutico , Tacrolimus/uso terapéutico , Adolescente , Adulto , Basiliximab , Cadáver , Niño , Preescolar , Quimioterapia Combinada , Femenino , Humanos , Inmunosupresores/uso terapéutico , Incidencia , Donadores Vivos , Masculino , Persona de Mediana Edad , Ácido Micofenólico/uso terapéutico , Donantes de Tejidos
16.
Ann Oncol ; 16(6): 928-33, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15851405

RESUMEN

BACKGROUND: Akt has been implicated in the oncogenesis of human malignant tumors, because Akt regulates many key effector molecules involved in cell survival. PTEN (phosphatase and tensin homolog deleted on chromosome 10) negatively regulates Akt activation. MATERIALS AND METHODS: The expression of phosphorylated Akt (p-Akt), total Akt and PTEN was analyzed by Western blotting in 45 renal cell carcinoma (RCC) patients. The Bad and phosphorylated Bad (p-Bad) statuses were analyzed in 20 RCC patients. A phosphatidylinositol ether analog was used as an Akt inhibitor to treat four RCC cell lines, namely Caki-1, KU19-20, SW839 and Caki-2. RESULTS: The PTEN expression in RCC was observed to decrease and p-Akt expression to increase significantly in comparison with that in the corresponding normal kidney tissue. The PTEN expression inversely correlated with the p-Akt expression. These alterations were specific for clear cell type RCC, but not for papillary or chromophobe type RCC. Alterations in Bad phosphorylation were also specifically observed in clear cell type. The Akt inhibitor induced apoptosis in KU19-20 and Caki-2 cells with a high Akt activity. CONCLUSIONS: A decreased expression of PTEN may be an underlying mechanism for Akt activation. An Akt inhibitor may be a therapeutic option for a subset of RCC with an elevated Akt activity.


Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma de Células Renales/metabolismo , Neoplasias Renales/metabolismo , Monoéster Fosfórico Hidrolasas/análisis , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Proto-Oncogénicas/fisiología , Proteínas Supresoras de Tumor/análisis , Carcinoma de Células Renales/patología , Proteínas Portadoras/fisiología , Línea Celular Tumoral , Humanos , Neoplasias Renales/patología , Fosfohidrolasa PTEN , Fosforilación , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Proteína Letal Asociada a bcl
17.
Br J Cancer ; 92(6): 1165-72, 2005 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-15756280

RESUMEN

Hypoxia is a key factor contributing to the progression of human neoplasias and to the development of resistance to chemotherapy. BNIP3 is a proapoptotic member of the Bcl-2 protein family involved in hypoxia-induced cell death. We evaluated the expression and methylation status of BNIP3 gene to better understand the role of epigenetic alteration of its expression in haematopoietic tumours. Methylation of the region around the BNIP3 transcription start site was detected in four acute lymphocytic leukaemia, one multiple myeloma and one Burkitt lymphoma cell lines, and was closely associated with silencing the gene. That expression of BNIP3 was restored by treatment with 5-aza2'-deoxycytidine (5-aza-dC), a methyltransferase inhibitor, which confirmed the gene to be epigenetically inactivated by methylation. Notably, re-expression of BNIP3 using 5-aza2-dC also restored hypoxia-mediated cell death in methylated cell lines. Acetylation of histone H3 in the 5' region of the gene, which was assessed using chromatin immunoprecipitation assays, correlated directly with gene expression and inversely with DNA methylation. Among primary tumours, methylation of BNIP3 was detected in five of 34 (15%) acute lymphocytic leukaemias, six of 35 (17%) acute myelogenous leukaemias and three of 14 (21%) multiple myelomas. These results suggest that aberrant DNA methylation of the 5' CpG island and histone deacetylation play key roles in silencing BNIP3 expression in haematopoietic tumours.


Asunto(s)
Metilación de ADN , Silenciador del Gen , Neoplasias Hematológicas/genética , Proteínas de la Membrana/genética , Proteínas Proto-Oncogénicas/genética , Secuencia de Bases , Línea Celular Tumoral , Islas de CpG , Humanos , Datos de Secuencia Molecular
18.
Prostate ; 62(1): 61-8, 2005 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-15389810

RESUMEN

BACKGROUND: The cross-talk between Wnt signaling and the Akt pathway in prostate cancer (Pca) is still unclear. In the present study, we found that WIF-1 downregulates the Akt pathway and also enhances chemosensitivity in PTEN-null Pca cells. METHODS: Wnt inhibitory factor-1 (WIF-1), an inhibitor of Wnt proteins, was transfected into PC-3 and DU145 Pca cells. RESULTS: Akt was phosphorylated in PTEN-null PC-3 cells but underphosphorylated in PTEN-expressed DU145 cells. The levels of phosphorylated Akt in WIF-1 overexpressing PC-3 cells were lower than those in native or control vector-transfected PC-3 cells. However, WIF-1 showed no additional inhibition of already reduced Akt activity in DU145 cells. Overexpression of WIF-1 resulted in sensitizing PC-3 cells for paclitaxel to induce apoptosis. DU145 cells were more sensitive to paclitaxel but were not affected by WIF-1 transfection. The PI3K inhibitor LY294002 seemed to restore the chemosensitivity of native PC-3 cells like WIF-1 did. CONCLUSIONS: Our results show that Wnt signaling is involved in Akt activation in Pca cells. Our data also indicate the possibility that Wnt and its signaling pathway can be therapeutic targets for PTEN-mutated advanced Pca.


Asunto(s)
Proteínas Portadoras/metabolismo , Resistencia a Antineoplásicos/fisiología , Neoplasias de la Próstata/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis , Proteínas Portadoras/genética , Línea Celular Tumoral , Proteínas del Citoesqueleto/metabolismo , Regulación hacia Abajo , Expresión Génica/fisiología , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Humanos , Masculino , Mutación , Fosfohidrolasa PTEN , Paclitaxel/uso terapéutico , Monoéster Fosfórico Hidrolasas/genética , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Proteínas Proto-Oncogénicas c-akt , Proteínas Represoras/genética , Transducción de Señal/fisiología , Transactivadores/metabolismo , Transfección , Proteínas Supresoras de Tumor/genética , beta Catenina
19.
Int J Oncol ; 25(4): 831-40, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15375530

RESUMEN

Hepatocyte growth factor (HGF), the ligand for the c-met proto-oncogene product, is a multifunctional protein that enhances tumor cell motility, extracellular matrix invasion, and mitogenic or morphogenic activities of various cell types. In this study we examined the expression of the c-Met receptor in human oral squamous cell carcinoma (SCC) in vivo and in vitro to explore its relationship to tumor progression and invasiveness. Biopsy specimens of human oral SCC were immunohistochemically stained for c-Met. Nearly all primary oral SCC lesions and lymph node metastases consistently showed intense staining for c-Met, whereas normal oral mucosa showed faint to negative staining only on basal cells. In a panel of human oral SCC cell lines, we found a strong correlation between the levels of c-Met expression and the cells' response to HGF in motility and invasion assays. Sensitivity to HGF also correlated with the expression of the c-Met 9-kb mRNA. When the non-invasive HOC-605 cell line, which expresses a low level of c-Met receptor, was transfected with an expression plasmid containing human c-met cDNA, the transfectant cells showed motile and invasive responses to HGF. Immunostaining and immunoprecipitation studies demonstrated that E-cadherin and c-Met were physically associated at SCC cell-cell junctions, suggesting a direct role for c-Met in induction of junctional integrity. Importantly, HGF caused a rapid elevation of unbound beta-catenin, suggesting its availability for nuclear signal transduction and triggering of cell motility and invasiveness. Thus, overexpression of c-Met may facilitate disruption of E-cadherin junctions. Collectively, these results suggest that HGF/c-Met signaling is a common event in oral SCC that may trigger phenotype modulation and enhanced invasion and metastasis.


Asunto(s)
Cadherinas/fisiología , Carcinoma de Células Escamosas/patología , Factor de Crecimiento de Hepatocito/farmacología , Uniones Intercelulares/fisiología , Neoplasias de la Boca/patología , Proteínas Proto-Oncogénicas c-met/fisiología , Northern Blotting , Cadherinas/análisis , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proteínas del Citoesqueleto/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Humanos , Inmunohistoquímica , Neoplasias de la Boca/metabolismo , Invasividad Neoplásica , Fosforilación , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-met/análisis , Transducción de Señal , Transactivadores/metabolismo , Tirosina/metabolismo , beta Catenina
20.
Br J Cancer ; 90(4): 844-52, 2004 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-14970863

RESUMEN

By presenting immunogenic peptides at the cell surface, major histocompatibility complex (MHC) class II molecules play a key role in the control of adaptive immune responses. Whether expressed constitutively or induced by interferon-gamma, expression of MHC class II molecules is regulated via coactivator class II transactivator (CIITA); moreover, suppression of their expression is one mechanism by which cancer cells escape host immunity. In this study, we surveyed the relationship between the expression of one MHC class II antigen, HLA-DR, and its coactivators in a group of haematopoietic cell lines, and explored the role of the aberrant DNA methylation in silencing HLA-DR expression. Among 26 cell lines studied, HLA-DR expression was lost from eight T-cell and two myeloid leukaemia cell lines, and this loss was closely associated with suppression of CIITA-PIV expression. Notably, nine of the 10 cell lines that lost CIITA-PIV expression showed methylation of the gene's 5' CpG island. Thus, DNA methylation is believed to inhibit the expression of MHC class II molecules in haematopoietic tumour cells by silencing its coactivator, CIITA-PIV. Furthermore, methylation of CIITA-PIV was detected in seven of 32 primary acute myeloid leukaemia specimens, indicating that epigenetic alteration is not a cell line-specific phenomenon. Collectively, these data suggest that, by suppressing expression of MHC class II molecules, epigenetic inactivation of CIITA provides a survival advantage to a subset of haematopoietic tumours.


Asunto(s)
Antineoplásicos/farmacología , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Antígenos HLA-DR/biosíntesis , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patología , Interferón gamma/farmacología , Proteínas Nucleares/metabolismo , Transactivadores/metabolismo , Acetilación , Supervivencia Celular , Citometría de Flujo , Genes MHC Clase II , Antígenos HLA-DR/inmunología , Histonas/metabolismo , Humanos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
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