RESUMEN
PURPOSE: The optimal macronutrient composition of the diet for the management of type 2 diabetes is debated, particularly with regard to the ideal proportion of fat and carbohydrates. The aim of the study was to explore the association of different proportions of fat and carbohydrates of the diet-within the ranges recommended by different guidelines-with metabolic risk factors. METHODS: We studied 1785 people with type 2 diabetes, aged 50-75, enrolled in the TOSCA.IT Study. Dietary habits were assessed using a validated food-frequency questionnaire (EPIC). Anthropometry, fasting lipids, HbA1c and C-reactive protein (CRP) were measured. RESULTS: Increasing fat intake from <25 to ≥35 % is associated with a significant increase in LDL-cholesterol, triglycerides, HbA1c and CRP (p < 0.05). Increasing carbohydrates intake from <45 to ≥60 % is associated with significantly lower triglycerides, HbA1c and CRP (p < 0.05). A fiber intake ≥15 g/1000 kcal is associated with a better plasma lipids profile and lower HbA1c and CRP than lower fiber consumption. A consumption of added sugars of ≥10 % of the energy intake is associated with a more adverse plasma lipids profile and higher CRP than lower intake. CONCLUSIONS: In people with type 2 diabetes, variations in the proportion of fat and carbohydrates of the diet, within the relatively narrow ranges recommended by different nutritional guidelines, significantly impact on the metabolic profile and markers of low-grade inflammation. The data support the potential for reducing the intake of fat and added sugars, preferring complex, slowly absorbable, carbohydrates.
Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Inflamación/sangre , Anciano , Proteína C-Reactiva/metabolismo , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Fibras de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Encuestas y Cuestionarios , Triglicéridos/sangreRESUMEN
BACKGROUND AND AIMS: Diabetic women have a more adverse plasma lipid profile than men. Sex differences in dietary habits may play a role, but are little investigated. The study evaluates the quality of diet, adherence to the nutritional recommendations of the Diabetes and Nutrition Study Group and their relation with plasma lipid in men and women with diabetes. METHODS AND RESULTS: We studied 2573 people, aged 50-75, enrolled in the TOSCA.IT study (clinicaltrials.gov; NCT00700856). Plasma lipids were measured centrally. Diet was assessed with a semi-quantitative food frequency questionnaire. Women had a more adverse plasma lipid profile than men. Women consumed significantly more legumes, vegetables, fruits, eggs, milk, vegetable oils, and added sugar, whereas men consumed more starchy foods, soft drinks and alcoholic beverages. This stands for a higher proportion (%) of energy intake from saturated fat and added sugar (12.0 ± 2.4 vs 11.5 ± 2.5 and 3.4 ± 3.2 vs 2.3 ± 3.2, P < 0.04), and a higher intake of fiber (11.2 ± 2.8 vs 10.4 ± 2.6 g/1000 Kcal/day) in women. Adherence to the recommendations for saturated fat and fiber consumption was associated with significantly lower LDL-cholesterol regardless of sex. Adherence to the recommendations for added sugars was associated with significantly lower triglycerides and higher HDL-cholesterol in men and women. CONCLUSIONS: Men and women with diabetes show significant differences in adherence to nutritional recommendations, but sex differences in plasma lipid profile are unlikely to be explained by nutritional factors. Adherence to the nutritional recommendations is associated with a better plasma lipid profile regardless of sex, thus reinforcing the importance of substituting saturated for unsaturated fat sources, increasing fiber and reducing added sugar intake.
Asunto(s)
Conducta de Elección , Diabetes Mellitus Tipo 2/dietoterapia , Dieta Saludable , Conducta Alimentaria , Lípidos/sangre , Cooperación del Paciente , Ingesta Diaria Recomendada , Anciano , Biomarcadores/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/psicología , Femenino , Preferencias Alimentarias , Humanos , Italia , Masculino , Persona de Mediana Edad , Evaluación Nutricional , Factores de Riesgo , Factores Sexuales , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del TratamientoRESUMEN
PURPOSE: Poor adherence to recombinant human growth hormone (r-hGH) therapy is associated with reduced growth velocity in children with growth hormone deficiency (GHD). This twelve-month observational study was to assess adherence in r-hGH patients treated with the easypod™, an electronic, fully automated injection device designed to track the time, date and dose administered. METHODS: Ninety-seven prepubertal patients receiving r-hGH therapy were included in the study from ten Italian clinical sites and 88 completed the study. To avoid possible confounding effects, only GHD patients (79/88; 89.7 % of the overall study population) were considered in the final analysis. The primary endpoint-adherence to treatment-was calculated as the proportion of injections correctly administered during the observational period out of the expected total number of injections. The relevant information, tracked by the easypod™, was collected at months 6 (V1) and 12 (V2) after baseline (V0). At study termination, adherence data were partially available from 16 patients and fully available from 53 patients. As secondary endpoints, serum IGF-1 levels, fasting serum glucose and insulin levels and key anthropometric characteristics (height, waist circumference and BMI) were also determined. RESULTS: The easypod™ data showed that 56.7 % of the patients were considered to be fully (≥92 %) adherent to their treatment throughout the period V0-V2. Treatment improved stature, significantly increased IGF-1 and produced a non-significant increase in blood glucose and insulin levels. CONCLUSIONS: The injection-recording system and other characteristics of easypod™ could enhance the ability of physicians to monitor adherence to r-hGH treatment.
Asunto(s)
Sistemas de Liberación de Medicamentos/instrumentación , Enanismo Hipofisario/tratamiento farmacológico , Electrónica/instrumentación , Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/administración & dosificación , Hormona de Crecimiento Humana/deficiencia , Cumplimiento de la Medicación , Glucemia/análisis , Niño , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Estudios ProspectivosRESUMEN
The c-fes protooncogene is expressed at high levels in the terminal stages of granulocytic differentiation, but so far no definite function has been attributed to the product of this oncogene. To tackle this problem, the c-fes protooncogene expression has been inhibited in HL60 cells, and fresh leukemic promyelocytes of acute promyelocytic leukemia have been induced to differentiate with retinoic acid (RA) and dimethylsulfoxide (DMSO). Inhibition was obtained by incubating the cells with a specific c-fes antisense oligodeoxynucleotide. It was observed that the cells, rather than differentiating, underwent premature cell death showing the morphological and molecular characteristics of apoptosis. This process was inhibited by granulocyte and granulocyte/macrophage colony-stimulating factor, but not by interleukin 3 (IL-3), IL-6, or stem cell factor. Our present results demonstrate that the loss of cell viability that occurs during the in vitro differentiation of myeloid cells, after the complete inhibition of the c-fes gene product and treatment with RA-DMSO, is due to activation of programmed cell death. It is concluded that a possible role of the c-fes gene product is to exert an antiapoptotic effect during granulocytic differentiation.
Asunto(s)
Apoptosis/genética , Expresión Génica/efectos de los fármacos , Granulocitos/citología , Oligonucleótidos Antisentido/farmacología , Proteínas Tirosina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Apoptosis/efectos de los fármacos , Secuencia de Bases , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Células Cultivadas , Dimetilsulfóxido/farmacología , Humanos , Datos de Secuencia Molecular , Proteínas Proto-Oncogénicas c-fes , Tretinoina/farmacologíaRESUMEN
A 10-year-old male intact Corso dog was referred for lameness and for a large neoplasm affecting the right foreleg. Physical examination of the patient revealed a 5 x 5 x 3 cm mass in the distal right foreleg. Histopathology was consistent with a diagnosis of appendicular osteosarcoma. The staging process found no evidence of metastasis. Because of the large size of the patient, the owners elected to treat their dog with antiresorptive therapy. The patient was treated with an infusion of zoledronic acid every 28 days. The tumour remained stable for 16 months and the lameness of the dog greatly improved. At that time, the patient returned for evaluation of a large rapidly growing prescapular mass. Biopsy confirmed lymph node metastasis and the dog was euthanased. Zoledronic acid showed remarkable palliation in our patient and possibly anti-tumour action and warrants further investigation.
Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Neoplasias Óseas/veterinaria , Difosfonatos/administración & dosificación , Enfermedades de los Perros/tratamiento farmacológico , Miembro Anterior , Imidazoles/administración & dosificación , Osteosarcoma/veterinaria , Animales , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/tratamiento farmacológico , Enfermedades de los Perros/diagnóstico por imagen , Perros , Eutanasia Animal , Miembro Anterior/diagnóstico por imagen , Cojera Animal/complicaciones , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Osteosarcoma/diagnóstico por imagen , Osteosarcoma/tratamiento farmacológico , Radiografía , Ácido ZoledrónicoRESUMEN
In this study, we have evaluated the effects on cell cycle regulation of VacA alone and in combination with other two Helicobacter pylori proteins, cytotoxin-associated protein (CagA) and HspB, using the human gastric epithelial cells (AGS). Our results indicate that VacA alone was able to inhibit the G1 to S progression of the cell cycle. The VacA capacity of inhibiting cell progression from G1 to S phase was also observed when cells were co-transfected with CagA or HspB. Moreover, VacA over-expression caused apoptosis in AGS cells through activation of caspase 8 and even more of caspase 9, thus indicating an involvement of both the receptor-mediated and the mitochondrial pathways of apoptosis. Indeed, the two pathways probably can co-operate to execute cell death with a prevalence of the mitochondrial pathways. Our data taken together provide additional information to further enhance our understanding of the molecular mechanism by which H. pylori proteins alter the growth status of human gastric epithelial cells.
Asunto(s)
Apoptosis , Proteínas Bacterianas/metabolismo , Ciclo Celular , Células Epiteliales/citología , Helicobacter pylori/metabolismo , Estómago/citología , Antígenos Bacterianos/metabolismo , Caspasas/metabolismo , Línea Celular , Activación Enzimática , Células Epiteliales/enzimología , Citometría de Flujo , Proteínas de Choque Térmico/metabolismo , Humanos , Immunoblotting , Proteína de Retinoblastoma/metabolismo , Estómago/enzimología , TransfecciónAsunto(s)
Trastornos del Desarrollo Sexual/historia , Medicina en las Artes , Arqueología , Historia Antigua , Humanos , Italia , MuseosRESUMEN
Cell cycle progression is mediated by a group of proteins named cyclins that activate a highly conserved family of protein kinases, the cyclin-dependent kinases (CDKs). CDKs are also regulated by related proteins called cdk inhibitors, grouped into two families: the INK4 inhibitors (p16, p15, p19 and p18) and the Cip/Kip inhibitors (p21, p27). Moreover, several tumour suppressor genes (such as Retinoblastoma gene and p53 gene) are implicated in the regulation of the molecular mechanism of cell division. Several studies report the importance of cell cycle regulator proteins in the pathogenesis and the prognosis of mesothelioma. This article will review the most recent data from the literature about the expression and the diagnostic and prognostic significance of cell cycle molecules in mesothelioma.
Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Mesotelioma/metabolismo , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/metabolismo , Quinasas Ciclina-Dependientes/genética , Quinasas Ciclina-Dependientes/metabolismo , Humanos , Mesotelioma/diagnóstico , Mesotelioma/epidemiología , Modelos BiológicosRESUMEN
Perianal tumors (adenoma and carcinoma of the hepatoid glands) are frequently reported in veterinary literature. They are locally aggressive tumors with a low tendency to metastatic spread. An hormonal ethiology has been identified for the development of perianal adenomas in male dogs, while the carcinomas are free from hormonal influence. Standard treatments include surgery, cryotherapy or, in selected cases, radiation therapy. In this article we describe the outcome of a small cohort of canine patients with perianal tumors treated with bleomycin selectively driven by trains of biphasic pulses (electrochemotherapy). Twelve canine patients, eight with adenoma and four with carcinoma of the perianal glands, entered the study and received two sessions of ECT under sedation. The pets had local injection ofbleomycin at the concentration of 1.5 mg/mg and five minutes after the chemotherapy, trains of 8 biphasic electric pulses lasting 50 + 50 micros each, with 1 ms interpulse intervals, were delivered by means of modified caliper and needle array electrodes or, for difficult districts, through paired needle electrode. The overall response rate was 91% with a 83% of complete response (10/12); one dog had a PR that lasted 12 months and another had progressive disease. Electrochemotherapy appears as a safe and efficacious modality for the treatment of perianal tumors and warrants further investigations.
Asunto(s)
Neoplasias de las Glándulas Anales/tratamiento farmacológico , Antibióticos Antineoplásicos/análisis , Bleomicina/análisis , Enfermedades de los Perros/tratamiento farmacológico , Electroquimioterapia/métodos , Animales , Antibióticos Antineoplásicos/uso terapéutico , Bleomicina/uso terapéutico , Terapia Combinada , Perros , Femenino , Masculino , Modelos AnimalesRESUMEN
Non Hogdkin's lymphoma is the commonest malignant neoplasm in humans and in pets. Treatments include systemic chemotherapy eventually combined with radiation therapy. Radiation therapy is also used as single agent for the treatment of localized lymphoma (LSA). Albeit efficacious, this modality is potentially associated with side effects. Purpose of this study was to preliminarily evaluate the feasibility and efficacy of electrochemotherapy (ECT) in companion animals with localized lymphoma. Six patients entered the study and received two sessions of ECT under sedation. The pets had local injection of bleomycin at the concentration of 1.5 mg/mg and five minutes after the chemotherapy, trains of 8 biphasic electric pulses lasting 50 + 50 micros each, with 1 ms interpulse intervals, were delivered by means of modified caliper electrodes or for difficult districts, through paired needle electrode. All the patients achieved complete responses (lasting 1 week through 3 years), one cat with nasal LSA had local recurrence and two others experienced spinal and intestinal relapse. Side effects were not noted with the exception of focal alopecia in a cat with retrobulbar LSA. Electrochemotherapy appears as a safe and efficacious modality for the treatment of localized lymphoma and warrants further investigations.
Asunto(s)
Electroquimioterapia , Linfoma no Hodgkin/veterinaria , Animales , Animales Domésticos , Bleomicina/uso terapéutico , Gatos , Perros , Linfoma no Hodgkin/tratamiento farmacológicoRESUMEN
A human lung tumor fetal-associated antigen (LTFA) has been purified from lung tumor tissue by a combination of salt precipitation and ion-exchange chromatography. The purification steps were monitored by double immunodiffusion with the use of a rabbit anti-LTFA-specific antiserum. The isolated protein was tested for its blastogenic properties toward peripheral blood lymphocytes (PBL) by [3H]thymidine incorporation. PBL obtained from 25 healthy individuals, 34 patients with tumors other than lung tumors, 13 patients with lung diseases other than lung tumors, and 51 lung tumor-bearing patients were tested. Only PBL with an in vitro positive response to phytohemagglutinin were employed. Whereas PBL of lung tumor patients showed a significant blastogenic response to the purified antigen in 14 of 22 patients tested (60%), PBL of other patients were completely unreactive (P less than 0.005). The present data suggested that a specific immune response toward an LTFA was present in patients with lung cancers.
Asunto(s)
Antígenos de Neoplasias/aislamiento & purificación , Neoplasias Pulmonares/inmunología , Activación de Linfocitos , Antígenos de Neoplasias/administración & dosificación , Células Cultivadas , Cromatografía por Intercambio Iónico , Feto/inmunología , Humanos , Inmunidad Celular , Enfermedades Pulmonares/inmunología , Fitohemaglutininas/farmacologíaRESUMEN
A human lung tumor-associated fetal antigen (LTFA) has been partially isolated and characterized. The antigen that differs in several immunochemical parameters from previously described lung cancer antigens was shared by fetal lung and liver tissue. The neoantigen migrated in immunoelectrophoresis as an alpha2-beta globulin, had an average molecular size of 7S, and was soluble in 50% saturated ammonium sulfate. Whereas LTFA was insensitive to both DNase and RNase treatment, its antigenicity was completely abolished by pronase. The biologic significance of this antigen and its possible clinical use were discussed.
Asunto(s)
Antígenos de Neoplasias , Carcinoma Broncogénico/inmunología , Neoplasias Pulmonares/inmunología , Pulmón/embriología , Antígenos de Neoplasias/aislamiento & purificación , Técnica del Anticuerpo Fluorescente , Humanos , Sueros Inmunes , Inmunodifusión , Inmunoelectroforesis , Pulmón/inmunologíaRESUMEN
BACKGROUND: Phosphorothioate oligodeoxynucleotides ([S]ODNs) contain a modified internucleoside phosphate backbone. Antisense [S]ODNs targeted to specific oncogenes have been used with some therapeutic success in animal models human leukemia; however, the potential for antisense [S]ODN treatment of solid tumors has only recently been explored. PURPOSE: We evaluated the effects of antisense [S]ODNs targeted to the c-myc oncogene on the proliferation of human melanoma cells in vitro and on the growth of human melanoma xenografts in CD-1 nude (nu/nu) mice, METHODS: The effects of 15-mer [S]ODNs containing c-myc sense, c-myc antisense, and two different scrambled sequences on the proliferation and viability of cultures of three established human melanoma cell lines (M14, JR8, and PLF2) were determined by measuring cell numbers and use of the trypan blue exclusion test. The induction of apoptosis in these cells following treatment with [S]ODNs was evaluated by fluorescence-activated cell sorter (FACS) analysis. FACS analysis was also used to determine the effects of [S]ODN treatment on the proliferation of primary cultures of a human melanoma explant (NG cells). The expression of c-Myc protein in cultured NG cells after treatment with [S]ODNs was examined by western blot analysis. The antitumor activity and the toxic effects of several [S]ODN treatment regimens were monitored by measuring differences in tumor weight (percent tumor weight inhibition), tumor growth rate (tumor growth inhibition), animal lifespan (percent increase in lifespan), the number of toxic deaths and the median number of long metastases in treated and control mice bearing NG xenografts. c-Myc protein expression in NG tumor cells following [S]ODN treatment was evaluated by FACS analysis, and the extent of apoptosis in these cells was determined by FACS analysis and morphologic examination. RESULTS: Treatment with antisense [S]ODNs, but not the others, inhibited the growth of all tested melanoma cultures in vitro; FACS analysis revealed that growth inhibition was associated with the induction of apoptosis. Antisense [S]ODN treatment also led to reduced celluLar levels of c-Myc protein. In vivo, [S]ODN antitumor activity and toxicity were dose and schedule dependent; however, only antisense [S]ODNs exhibited antitumor activity. Mice bearing NG xenografts treated with antisense [S]ODNs showed a marked inhibition of tumor growth, a reduction in the number of long metastases, and an increase in life span. Reduced levels of c-Myc protein and increased levels of apoptosis were also observed in NG tumor cells following antisense [S]ODN treatment. CONCLUSIONS: treatment of human melanoma cells and solid tumors with antisense [S]ODNs targeted to c-Myc inhibits their growth and is associated with the induction of apoptosis.
Asunto(s)
Antineoplásicos/uso terapéutico , Ciclo Celular/efectos de los fármacos , Genes myc , Melanoma/tratamiento farmacológico , Oligonucleótidos Antisentido/uso terapéutico , Proteínas Proto-Oncogénicas c-myc/genética , Animales , Apoptosis/efectos de los fármacos , Secuencia de Bases , Western Blotting , División Celular/efectos de los fármacos , Esquema de Medicación , Citometría de Flujo , Humanos , Melanoma/patología , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Proteínas Proto-Oncogénicas c-myc/biosíntesis , ARN Mensajero/metabolismo , Tionucleótidos , Factores de Tiempo , Trasplante Heterólogo , Células Tumorales CultivadasRESUMEN
This study was designed to assess the efficacy of a new antimelanoma therapeutic strategy that relies on the use of a c-myc antisense 15-mer phosphorothioate oligodeoxynucleotide ([S]ODN), in combination with cisplatin (cis-diamminedichloroplatinum; DDP), which is currently used in the clinical management of melanoma patients. Proliferation and colony formation of melanoma cells were both inhibited by the DDP/c-myc antisense [S]ODN combination to a greater extent than that observed with either agent alone. Inhibition was most effective when DDP was followed by c-myc antisense [S]ODNs. Cell cycle flow cytometric analysis of cells exposed to the two agents either alone or in combination demonstrated that (a) c-myc antisense [S]ODNs induced an accumulation of cells in S phase and apoptosis in a fraction of the cells, detectable at day 5 after the beginning of treatment; (b) DDP induced a block in G2-M phase detectable at day 1, which was partially recovered, and apoptosis similar in extent to that induced by c-myc antisense [S]ODNs; and (c) DDP and c-myc antisense [S]ODNs together induced arrest in G2-M phase, which was maximum at day 3, i.e., delayed as compared to the block induced by DDP. The combination induced a higher percentage of apoptosis, evident at day 3 from the start of treatment, that correlated with a marked reduction in Bcl-2 expression. Mice bearing human melanoma xenografts and treated sequentially with DDP and c-myc antisense [S]ODNs showed a higher inhibition of tumor growth, reduction in the number of lung metastases, and increase in life span compared with those treated with either agent alone. Together, these data lend support to the development of anticancer therapies involving oncogene-targeted antisense ODNs and conventional antineoplastic drugs.
Asunto(s)
Antineoplásicos/farmacología , Cisplatino/farmacología , Genes myc/genética , Melanoma Experimental/tratamiento farmacológico , Oligonucleótidos Antisentido/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , ADN de Neoplasias/análisis , Sinergismo Farmacológico , Quimioterapia Combinada , Citometría de Flujo , Humanos , Masculino , Melanoma Experimental/patología , Ratones , Ratones Desnudos , Oligonucleótidos Antisentido/genética , Neoplasias Cutáneas/patología , TionucleótidosRESUMEN
In recent years, increasing evidence indicated the importance of a deregulated c-myc gene in the melanoma pathogenesis. We have previously demonstrated that treatment of melanoma cells with c-myc antisense oligodeoxynucleotides can inhibit cell proliferation and activate apoptosis. To gain insight into the mechanisms activated by Myc down-regulation, we have now developed an experimental model that allows modulating Myc protein expression in melanoma cells. This was achieved by originating stable melanoma cell clones expressing ecdysone-inducible c-myc antisense RNA. We show that the induction of c-myc antisense RNA in M14 melanoma cells leads to an inhibition of cell proliferation characterized by accumulation of cells in the G(1) phase of the cell cycle (up to 80%) and activation of apoptosis (50%). These data are associated with an increase of p27(kip1) levels and a significant reduction of the cdk2-associated kinase activity. In addition, we show that an ectopic overexpression of p27(kip1) in this experimental model can enhance the apoptotic rate. Our results indicate that down-regulation of Myc protein induces a G(1) arrest and activates apoptosis by increasing p27(kip1) content in melanoma cells, that are known to be defective for the p16-cyclinD/cdk4-pRb G(1) checkpoint. This is particularly relevant for identifying new therapeutic strategies based on the re-establishment of the apoptotic pathways in cancer cells.
Asunto(s)
Apoptosis/fisiología , Proteínas de Ciclo Celular , Melanoma/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN sin Sentido/metabolismo , Proteínas Supresoras de Tumor , Western Blotting , División Celular/fisiología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Ciclinas/metabolismo , Regulación hacia Abajo , Fase G1/fisiología , Humanos , Melanoma/patología , Células Tumorales CultivadasRESUMEN
Antibodies were raised in a rabbit by using a 12-residue synthetic peptide, corresponding to fragment 2-13 of rat placental glutathione S-transferase, as the immunogen. The antiserum appeared to react with the fragment as well as with the corresponding human enzyme (GST-pi), which shares with the rat transferase a 92% sequence homology at the N terminus. In addition, the binding of the antibody to the protein was completely inhibited by small amounts of peptide. The enzymatic activity of glutathione transferase was not affected by the antibody. This might indicate that the N-terminal fragment is not involved in the catalytic activity of the enzyme. This antibody of predetermined specificity might thus find a useful application for the detection and approximate quantitation of this marker in human preneoplastic lesions.
Asunto(s)
Glutatión Transferasa/análisis , Secuencia de Aminoácidos , Animales , Anticuerpos/inmunología , Glutatión Transferasa/inmunología , Humanos , Datos de Secuencia Molecular , Fragmentos de Péptidos/inmunología , ConejosRESUMEN
We have produced a polyclonal antibody that specifically recognizes cGMP-binding cGMP-specific phosphodiesterase (PDE5). The antibody was raised in rabbit using as immunogen a fusion protein, in which glutathione S-transferase was coupled to a 171 amino acid polypeptide of the N-terminal region of bovine PDE5. The antibody is able to immunoprecipitate PDE5 activity from mouse tissues and neuroblastoma extracts while it has no effect on all other PDE isoforms present in the extracts. PDE5 activity recovered in the immunoprecipitates retains its sensitivity to specific inhibitors such as zaprinast (IC(50)=0.6 microM) and sildenafil (IC(50)=3.5 nM). Bands of the expected molecular mass were revealed when solubilized immunoprecipitates were analysed in Western blots. The antibody selectively stained cerebellar Purkinje neurones, which are known to express high levels of PDE5 mRNA. Western blot analysis of mouse tissues revealed the highest expression signal in mouse lung, followed by heart and cerebellum, while a lower signal was evident in brain, kidney and a very low signal was present in the liver. In the hybrid neuroblastoma-glioma NG108-15 cells the antibody revealed a high PDE5 induction after dibutyryl-cAMP treatment.
Asunto(s)
3',5'-GMP Cíclico Fosfodiesterasas/metabolismo , 3',5'-GMP Cíclico Fosfodiesterasas/análisis , 3',5'-GMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , 3',5'-GMP Cíclico Fosfodiesterasas/inmunología , Animales , Especificidad de Anticuerpos , Western Blotting , Encéfalo/enzimología , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5 , Sueros Inmunes/inmunología , Inmunohistoquímica , Hígado/enzimología , Pulmón/enzimología , Ratones , Miocardio/enzimología , Inhibidores de Fosfodiesterasa/farmacología , Piperazinas/farmacología , Pruebas de Precipitina , Purinas , Purinonas/farmacología , Citrato de Sildenafil , Sulfonas , Extractos de Tejidos/química , Células Tumorales CultivadasRESUMEN
Cyclooxygenases catalyze the initial, rate-limiting steps of prostaglandin synthesis from arachidonic acid. Two isoforms of this enzyme exist in mammalian and avian species: COX-1 and COX-2. COX-1 is constitutively expressed and is the major isoform of gastrointestinal tissue. COX-2 is induced in response to inflammatory stimuli. COX-2 has been implicated in carcinogenesis of several neoplasms. Furthermore, COX-2 over-expression has been noted in many solid tumours and has been correlated with a worse prognosis in colorectal cancer, non-small-cell lung cancer, mesothelioma and gastric cancer. In this review, the most recent findings on the mechanisms by which COX-2 promote tumorigenesis are discussed, with particular emphasis on the studies involving spontaneous canine neoplasms.
Asunto(s)
Ciclooxigenasa 2/biosíntesis , Ciclooxigenasa 2/genética , Enfermedades de los Perros/enzimología , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Animales , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Perros , Neoplasias/epidemiologíaRESUMEN
Cyclooxygenases catalyze the rate limiting step in the production of prostanoids. Accumulating data demonstrate that overexpression of these enzymes, and in particular of cyclooxygenases-2, promotes multiple events involved in tumorigenesis; in addition, numerous studies show that inhibition of cyclooxygenases-2 can delay or prevent certain forms of cancer. Malignant mesothelioma is a lethal pleural, peritoneal and pericardial neoplasia that actually lacks valid therapies and in which cyclooxygenases-2 is recognized as an important adverse prognostic factor. Hence, there is an increasing interest in the development of new treatments based on cyclooxygenases-2 inhibitors, to prolong survival and even potentially cure this neoplasia.
Asunto(s)
Ciclooxigenasa 2/química , Ciclooxigenasa 2/fisiología , Proteínas de la Membrana/química , Proteínas de la Membrana/fisiología , Mesotelioma/enzimología , Animales , Ciclooxigenasa 1/química , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 1/fisiología , Ciclooxigenasa 2/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Mesotelioma/tratamiento farmacológico , Mesotelioma/etiología , Relación Estructura-ActividadRESUMEN
BACKGROUND: Experimental evidence suggests that lung cancer development and progression can be linked to an increased proliferation rate. AIMS/METHODS: To evaluate the immunohistochemical expression of seven components of the cell cycle machinery in a series of well characterised non-small cell lung cancer (NSCLC) specimens (n = 105). RESULTS: Multivariate analysis revealed that simultaneous loss of expression of three of these factors--cyclin D1, the cyclin dependent kinase inhibitor p16, and the tumour suppressor retinoblastoma protein Rb2/p130--correlated with survival, confirming the hypothesis that the cyclin D1-p16-retinoblastoma tumour suppressor pathway is inactivated in most lung cancer samples. CONCLUSIONS: These results suggest that loss of control of cell cycle checkpoints is a common occurrence in lung cancer and support the idea that functional cooperation between different cell cycle regulatory proteins constitutes another level of regulation in cell growth control and tumour suppression.