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1.
BMC Cancer ; 22(1): 1258, 2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36463104

RESUMEN

BACKGROUND: We evaluated a new chemoimmunotherapy combination based on the anti-PD1 monoclonal antibody pembrolizumab and the pyrimidine antimetabolite gemcitabine in HER2- advanced breast cancer (ABC) patients previously treated in the advanced setting, in order to explore a potential synergism that could eventually obtain long term benefit in these patients. METHODS: HER2-negative ABC patients received 21-day cycles of pembrolizumab 200 mg (day 1) and gemcitabine (days 1 and 8). A run-in-phase (6 + 6 design) was planned with two dose levels (DL) of gemcitabine (1,250 mg/m2 [DL0]; 1,000 mg/m2 [DL1]) to determine the recommended phase II dose (RP2D). The primary objective was objective response rate (ORR). Tumor infiltrating lymphocytes (TILs) density and PD-L1 expression in tumors and myeloid-derived suppressor cells (MDSCs) levels in peripheral blood were analyzed. RESULTS: Fourteen patients were treated with DL0, resulting in RP2D. Thirty-six patients were evaluated during the first stage of Simon's design. Recruitment was stopped as statistical assumptions were not met. The median age was 52; 21 (58%) patients had triple-negative disease, 28 (78%) visceral involvement, and 27 (75%) ≥ 2 metastatic locations. Progression disease was observed in 29 patients. ORR was 15% (95% CI, 5-32). Eight patients were treated ≥ 6 months before progression. Fourteen patients reported grade ≥ 3 treatment-related adverse events. Due to the small sample size, we did not find any clear association between immune tumor biomarkers and treatment efficacy that could identify a subgroup with higher probability of response or better survival. However, patients that experienced a clinical benefit showed decreased MDSCs levels in peripheral blood along the treatment. CONCLUSION: Pembrolizumab 200 mg and gemcitabine 1,250 mg/m2 were considered as RP2D. The objective of ORR was not met; however, 22% patients were on treatment for ≥ 6 months. ABC patients that could benefit of chemoimmunotherapy strategies must be carefully selected by robust and validated biomarkers. In our heavily pretreated population, TILs, PD-L1 expression and MDSCs levels could not identify a subgroup of patients for whom the combination of gemcitabine and pembrolizumab would induce long term benefit. TRIAL REGISTRATION: ClinicalTrials.gov and EudraCT (NCT03025880 and 2016-001,779-54, respectively). Registration dates: 20/01/2017 and 18/11/2016, respectively.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Persona de Mediana Edad , Antígeno B7-H1 , Mama , Neoplasias de la Mama/tratamiento farmacológico , Gemcitabina
3.
Clin Transl Oncol ; 18(8): 805-12, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26542177

RESUMEN

PURPOSE: The treatment of recurrent high-grade gliomas (HGG) is controversial. There are different therapeutic schedules but without a clear orientation about which of them should be used in each clinical situation. In addition, when patients suffer a second recurrence or they have poor performance status, they are excluded from clinical trials, although second recurrences and poor performance status are indeed more and more real and common situations in the clinical setting. In this study, we assessed the efficacy and safety of fotemustine (FTM) in HGG [fundamentally, glioblastomas (GB)], independent of time of recurrence or performance status. METHODS/PATIENTS: Retrospective study in HGG patients treated with FTM in second or further line according to standard, the Addeo or any other scheme, starting treatment prior to 30 November 2012. Included patients reflect the regular situation in which the drug is used in terms of comorbidities and analytic situation (hematologic, renal and hepatic functions). Response assessment was performed by MRI and according to the clinical protocols of each center (every 8-12 weeks). Clinical situation and supportive care drugs were evaluated in each medical consultation. Clinical end-points analyzed, among others, were: PFS-6, PFS, OS, response rates, toxicity, quality of life and neurocognitive impact. RESULTS: In terms of activity, an overall response rate of 8 % was observed: partial response 6 % (7 patients) and complete response 2 % (2 patients). The median time to achieve the greater response with FTM was 73 days (4-841 days). Patients treated according to the Addeo schedule had a shorter time to greater response in comparison with other schedules (85.9 vs 114 days), although without statistical significance. There were no significant differences in progression-free survival (PFS) when comparing different FTM schedules or using FTM in first or second recurrence. Median PFS: 3 months. PFS-6: 30.3 %. Overall survival (OS): although without significant differences, a tendency to better survival when using the Addeo schedule versus other schedules was observed (at 6 months, 44.6 vs 34.5 %; at 12 months, 25 vs 23.6 %; at 18 months, 11.5 vs 7.9 %), as well as if earlier use (second vs third line) concerning OS-12 (33.7 vs 18.2 %). Median OS: 5.2 months. Grades 3-4 toxicity was 28 % (31 patients), being neutropenia (4 %) and thrombocytopenia (17 %) the most frequent adverse reactions. From quality of life and neuro-cognitive function perspectives, 11 patients (10 %) and 16 (14 %) improved the Karnofsky Index and neurological impairment, respectively, after FTM treatment. CONCLUSION: This study has shown that FTM is safe and has a comparable activity with other available therapeutic options of use in the treatment of recurrent HGG.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Compuestos de Nitrosourea/uso terapéutico , Compuestos Organofosforados/uso terapéutico , Adulto , Anciano , Neoplasias Encefálicas/mortalidad , Femenino , Glioma/mortalidad , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
4.
Biochim Biophys Acta ; 949(1): 58-64, 1988 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-3334851

RESUMEN

The human CuZn superoxide dismutase (superoxide dismutase 1) a key enzyme in the metabolism of oxygen free-radicals, is encoded by a gene located on chromosome 21 in the region 21 q 22.1 known to be involved in Down's syndrome. A gene dosage effect for this enzyme has been reported in trisomy 21. To assess the biological consequences of superoxide dismutase 1 overproduction within cells, the human superoxide dismutase 1 gene and a human superoxide dismutase 1 cDNA were introduced into mouse L cells and NS20Y neuroblastoma cells. Both cell types expressed elevated levels (up to 3-fold) of enzymatically active human superoxide dismutase 1. These human superoxide dismutase 1 overproducers, especially neuronal cell lines, showed an increased activity in the selenodependent glutathione peroxidase. These data are consistent with the possibility that gene dosage of superoxide dismutase 1 contributes to oxygen metabolism modifications previously described in Down's syndrome.


Asunto(s)
Genes , Glutatión Peroxidasa/metabolismo , Superóxido Dismutasa/genética , Transcripción Genética , Transfección , Animales , Línea Celular , Humanos , Células L/enzimología , Ratones , Neuroblastoma/enzimología , Hibridación de Ácido Nucleico , Superóxido Dismutasa/metabolismo
5.
Mech Ageing Dev ; 96(1-3): 59-73, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9223111

RESUMEN

The human Cu/Zn superoxide dismutase (hSOD-1) gene, catalyses the dismutation of O2 to H2O2 and O2. It is located on chromosome 21 in q22.1 and is overexpressed in Down's syndrome (DS) patients. These patients present various abnormalities including mental retardation, congenital heart disease, immunological deficits and premature aging. In order to explore the potential role of SOD-1 overexpression in DS, we have generated two lineages of transgenic mice for the hSOD-1 gene and studied, at the ultrastructural level, the effect of hSOD-1 overexpression on the thymic microenvironment. Modification of the cellular architecture and morphology associated with a lipidic invasion, signs of a premature involution of the thymus, were observed in both lineages. A rupture of the filamentous network in the extracellular and probably also in the intracellular matrix was first observed. These results correlate the thymic alterations visualized in light microscopy, on the thymus from DS patients, and raise the question of the relationship between the SOD-1 overexpression and the different morphological alterations associated with the premature thymic involution observed in SOD-1 transgenic mice. They suggest that thymic and immunological impairments present in DS patients may be related to the SOD-1 gene dosage effect.


Asunto(s)
Envejecimiento/fisiología , Superóxido Dismutasa/genética , Timo/crecimiento & desarrollo , Animales , Humanos , Ratones , Ratones Endogámicos , Ratones Transgénicos , Timo/ultraestructura
6.
Kidney Int Suppl ; 78: S243-5, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11169019

RESUMEN

Moderate hyperhomocyst(e)inemia and impaired endothelium-dependent vasodilatation are present in uremic patients. However, the precise mechanism(s) underlying the link between moderate hyperhomocyst(e)inemia and endothelium dysfunction in uremic patients remains to be determined. Experimental and clinical evidence have led to the suggestion that moderate hyperhomocyst(e)inemia may predispose to endothelium dysfunction through a mechanism that involves generation of reactive oxygen species and a decrease in nitric oxide bioavailability. Recent preliminary findings in uremic patients provide support for some aspects of this suggestion. These data must be confirmed in additional studies. Moreover, the relative importance of homocysteine-induced oxidant stress versus other potential mechanisms of endothelium dysfunction in these patients remains to be determined.


Asunto(s)
Endotelio Vascular/fisiopatología , Homocisteína/metabolismo , Homocistina/metabolismo , Uremia/metabolismo , Uremia/fisiopatología , Animales , Arteriosclerosis/etiología , Arteriosclerosis/fisiopatología , Arteriosclerosis/prevención & control , Humanos , Hiperhomocisteinemia/etiología , Hiperhomocisteinemia/metabolismo , Óxido Nítrico/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Uremia/complicaciones , Vasodilatación/fisiología
7.
Neurosci Lett ; 92(3): 247-53, 1988 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-3200483

RESUMEN

The distribution of cells containing CuZn superoxide dismutase (CuZn SOD) was determined in hippocampi and associative cortex from normal and Alzheimer's individuals by using antisera against native and denatured CuZn SOD proteins. Immunostaining was intense in large pyramidal neurons, moderate in hippocampal granule cells and very weak in other cells. In the hippocampus of an Alzheimer's patient, successive immunostaining of the same tissue section by anti CuZn SOD and anti paired helical filaments antisera show that both normal and degenerating cells are labelled by the anti CuZn SOD antiserum. Thus, large pyramidal neurons which are potentially susceptible to degenerative processes in AD have the property to contain higher amounts of CuZn SOD than other brain cells.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Corteza Cerebral/enzimología , Superóxido Dismutasa/análisis , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Corteza Cerebral/patología , Hipocampo/enzimología , Hipocampo/patología , Humanos , Inmunohistoquímica , Persona de Mediana Edad
8.
Neurosci Lett ; 105(1-2): 41-6, 1989 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-2485884

RESUMEN

The cellular localization of copper-zinc superoxide dismutase (CuZn SOD) mRNA was determined in the human hippocampus by in situ hybridization with a 35S-labelled DNA probe complementary to human CuZn SOD mRNA. A positive hybridization signal was detected in pyramidal cell layers CA1-CA4 of Ammon's horn (CA), pyramidal cells of subiculum and in the granule cells of the dentate gyrus. The fact that CuZn SOD gene expression is important in neurones which are preferentially vulnerable in neurodegenerative processes such as Alzheimer's disease, suggests a role played by oxygen free radicals in the mechanism of nerve cell death.


Asunto(s)
Cobre/metabolismo , Hipocampo/enzimología , ARN Mensajero/metabolismo , Superóxido Dismutasa/metabolismo , Zinc/metabolismo , Anciano , Anciano de 80 o más Años , Autorradiografía , ADN/metabolismo , Hipocampo/citología , Humanos , Hibridación de Ácido Nucleico , Plásmidos , Superóxido Dismutasa/química
9.
Clin Chim Acta ; 188(2): 101-8, 1990 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-2379310

RESUMEN

In order to assess the influence of renal failure and nutritional status on the fasting concentrations of free plasma amino acids, we studied 81 ambulatory adult patients with varying degrees of chronic renal failure. Each of the patients was in good general and nutritional condition. Compared to 33 healthy controls, patients with mild renal failure (Ccr greater than 25 ml/mn) exhibited significantly (p less than 0.01, Student's t test) raised concentrations of cystine, citrulline, ornithine, taurine and 3-methyl-histidine and low level of serine. Concentrations of cystine, citrulline, and 3-methyl-histidine in plasma but not of taurine or ornithine rose in parallel with the progression of renal failure. A significant, but moderate decrease in valine, leucine and isoleucine concentrations was observed in patients with the most marked degree of renal failure (Ccr less than 10 ml/mn). We conclude that changes in the plasma concentration of several non essential amino acids are already present in the early stage of renal failure in patients with no sign of protein malnutrition: these may result from altered metabolic pathways of amino acids related to uremia and/or nephron loss per se whereas the moderate decrease in branched-chain amino acids that is observed only in the advanced stage of renal failure may be, at least in part, nutritional in origin.


Asunto(s)
Aminoácidos/sangre , Fallo Renal Crónico/sangre , Adulto , Anciano , Citrulina/sangre , Cistina/sangre , Femenino , Humanos , Masculino , Metilhistidinas/sangre , Persona de Mediana Edad
13.
J Pharmacol ; 15(3): 319-30, 1984.
Artículo en Francés | MEDLINE | ID: mdl-6208429

RESUMEN

Hemispheric ischemia was induced in normothermic, artificially ventilated and anesthetized rats, by electrocauterization of the vertebral arteries and a transient occlusion of the common carotid arteries for 10 minutes. Cerebrospinal fluid (CSF) was continuously pumped out of the third cerebral ventricle for potassium, dopamine and serotonin metabolite determinations. Levels were stable until ischemia, which interrupted the CSF production. During early recirculation a marked increase in dopamine metabolites occurred. The metabolite of serotonin increased slightly with a delay. Potassium in CSF was transitorily increased following ischemia. Reserpine pretreatment prevented most of the changes such as the early increase in dopamine metabolites. A delayed increase of these metabolites was still observed. This model of short ischemia altered the neurological functioning and survival time of the animals especially 15 minutes after removal of bilateral carotid occlusion, as compared to the later periods of observation. This model is therefore applicable to the study of cerebral alterations secondary to ischemia in vivo. The presently observed alterations of metabolite levels could reflect an increased neuronal release of parents monoamines that could participate to the neurological deficit.


Asunto(s)
Isquemia Encefálica/líquido cefalorraquídeo , Dopamina/líquido cefalorraquídeo , Serotonina/líquido cefalorraquídeo , Ácido 3,4-Dihidroxifenilacético/líquido cefalorraquídeo , Animales , Isquemia Encefálica/complicaciones , Hidrato de Cloral/farmacología , Ácido Homovanílico/líquido cefalorraquídeo , Ácido Hidroxiindolacético/líquido cefalorraquídeo , Masculino , Enfermedades del Sistema Nervioso/etiología , Pentobarbital/farmacología , Potasio/farmacología , Ratas , Ratas Endogámicas , Reserpina/farmacología , Factores de Tiempo
14.
Lab Invest ; 74(3): 617-26, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8600312

RESUMEN

It has been suggested that the overexpression of copper-zinc superoxide dismutase (SOD-1) in Down's syndrome (DS) patients may be involved in expression of some of the phenotypic characteristics observed in these patients. To explore the possible role of SOD-1 overexpression in the premature thymic involution and immunologic disorders observed in DS patients, transgenic mice overexpressing the human SOD-1 gene have been generated and their thymuses have been studied at the ultrastructural level. Our observations show premature involution of the thymus in SOD-1 transgenic mice, with a strong modification of the thymic microenvironment starting at approximately 3-4 months of age. The thymic microenvironment in 7-month-old transgenic mice is similar to that observed in 20-month-old control mice. We suggest that these results are consistent with the role of SOD-1 overexpression in the early thymic involution observed in DS patients. These transgenic mice provide an interesting model to investigate the deleterious effect of increased dosage of some chromosome 21 genes such as SOD-1 in the pathogenesis of DS.


Asunto(s)
Síndrome de Down/enzimología , Síndrome de Down/genética , Superóxido Dismutasa/genética , Timo/enzimología , Timo/ultraestructura , Animales , Modelos Animales de Enfermedad , Síndrome de Down/patología , Femenino , Regulación Enzimológica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Ratones Transgénicos , Microscopía Electrónica
15.
Biochem Biophys Res Commun ; 128(1): 40-4, 1985 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-3157380

RESUMEN

The enzymatic activity of cystathionine beta synthase has been studied in fibroblasts of nine patients with regular trisomy 21. An excess of CBS activity was found in trisomy 21 with a trisomy 21/normal ratio equal to 1.66. A 1.04 ratio was found in 21q21----21 p ter monosomy; a 1.04 and 0.99 ratio was found in two 21 qter----21q22.3 monosomies; a 1.14 ratio in 21 qter----21q22 monosomy; a 0.89 ratio in a 21q21----21 pter trisomy; an excess of CBS activity was found in a 21q22.1 ----21q21 trisomy with a 1.57 ratio. These results show a gene dosage effect in human fibroblasts trisomic for chromosome 21 and suggest the assignment of human CBS locus between 21q22.1 and 21q21.


Asunto(s)
Cistationina betasintasa/genética , Compensación de Dosificación (Genética) , Síndrome de Down/enzimología , Hidroliasas/genética , Adolescente , Células Cultivadas , Bandeo Cromosómico , Cromosomas Humanos 21-22 e Y , Síndrome de Down/genética , Femenino , Fibroblastos/enzimología , Heterocigoto , Homocigoto , Humanos , Lactante , Masculino
16.
Free Radic Res Commun ; 12-13 Pt 2: 581-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1829430

RESUMEN

It was suggested that increased Cu-Zn superoxide dismutase (SOD-1) might be involved in the various biological abnormalities found in Down's syndrome (DS) such as premature aging and Alzheimer-type neurological lesions. As a model system for testing this hypothesis we have developed two strains of transgenic mice carrying only one copy of the human SOD-1 gene. In the first strain (TG1), no expression has been found by northern blot analysis. The second strain (TG2) exhibited human SOD-1 mRNA and increased SOD-1 activity in the brain (1.93 fold), in the heart (1.69 fold), thymus (1.49 fold) and to a lesser extent in muscle (1.25 fold), liver (1.19 fold), kidney (1.18 fold), spleen (1.35 fold), lung (1.26 fold) and erythrocytes (1.09 fold). In this strain, increased SOD-1 activity in the brain did not induce modifications in the seleno-dependent glutathione peroxidase, glutathione reductase and glutathione S-transferase activities. In brain homogenates, we have focused our studies on Tau proteins which are known to be the major antigenic components of paired helical filaments (PHF), both in DS and Alzheimer's disease. Our results suggested that, in our experimental conditions, the overexpression of SOD-1 did not induce the modifications of Tau proteins similar to those seen during neurofibrillary degeneration.


Asunto(s)
Síndrome de Down/genética , Regulación Enzimológica de la Expresión Génica/fisiología , Modelos Genéticos , Superóxido Dismutasa/genética , Animales , Encéfalo/enzimología , Cobre/química , Modelos Animales de Enfermedad , Radicales Libres , Humanos , Immunoblotting , Ratones , Ratones Transgénicos , Proteínas Asociadas a Microtúbulos/análisis , Proteínas del Tejido Nervioso/análisis , Oxígeno/química , Zinc/química , Proteínas tau
17.
Free Radic Res Commun ; 12-13 Pt 2: 571-80, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2060834

RESUMEN

The distribution of cells containing copper-zinc superoxide dismutase (CuZn SOD) protein and mRNA was studied in hippocampi from normal humans and patients with Alzheimer's disease (AD) by using immunohistochemistry and in situ hybridization. Using antisera against native and denatured CuZn SOD protein, we have determined that immunostaining was intense in pyramidal neurons of the cornu ammonis, in granule cells of the dentate gyrus and very weak in other cells. In the hippocampus of an Alzheimer's patient, successive immunostaining of the same tissue section by antiCuZn SOD and antipaired helical filaments antisera show that both normal and degenerating cells were labeled by the antiCuZn SOD antiserum. Thus, large pyramidal neurons which are susceptible to degenerative processes in AD have the property to contain high amount of CuZn SOD protein. In situ hybridization was performed on paraformaldehyde-fixed hippocampus sections of normal human brains and AD brains with a 35 S labeled DNA probe homologous to human CuZn SOD mRNA. Our results show that CuZn SOD transcripts are present at high abundance in pyramidal neurons of the CA1-CA4 fields, subiculum, and in granule cells of the dentate gyrus. This cellular distribution is similar to that obtained with the antiCuZn SOD antiserum. This might indicate that biochemical pathways leading to superoxide radicals generation are specially active in these neurons, requiring an active transcription of CuZn-SOD gene.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Hipocampo/enzimología , Neuronas/enzimología , ARN Mensajero/análisis , Superóxido Dismutasa/análisis , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/metabolismo , Supervivencia Celular/fisiología , Cobre/química , Radicales Libres , Hipocampo/química , Hipocampo/citología , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Neuronas/química , Hibridación de Ácido Nucleico , Valores de Referencia , Superóxido Dismutasa/genética , Zinc/química
18.
Ann Genet ; 29(4): 226-8, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3495222

RESUMEN

We have analyzed the DNA from four patients suffering from a dementia of the Alzheimer type and of four controls of identical age. Estimates of the copy numbers of two genes located on chromosome 21, SOD1 and ETS2, gave the following results: in all the cases there was duplication of ETS2 whereas SOD1 was normal. These preliminary results indicate that the segment of chromosome 21(q21----q22.1) is rearranged in all the four patients who were investigated.


Asunto(s)
Enfermedad de Alzheimer/genética , Aberraciones Cromosómicas/genética , Cromosomas Humanos Par 21 , Trastornos de los Cromosomas , Clonación Molecular , Humanos
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