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1.
Ann Oncol ; 23(9): 2265-2271, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22377563

RESUMEN

BACKGROUND: Recurrent platinum-resistant ovarian cancer usually has a poor outcome with conventional chemotherapeutic therapy and new treatment modalities are warranted. This phase II study was conducted to evaluate sunitinib, an oral antiangiogenic multitargeted tyrosin kinase inhibitor, in this setting. MATERIAL AND METHODS: The primary end point of this randomized phase II trial was the objective response rate according to RECIST criteria and/or Gynecologic Cancer InterGroup CA125 response criteria to sunitinib in patients with recurrent platinum-resistant ovarian cancer who were pretreated with up to three chemotherapies. A selection design was employed to compare two schedules of sunitinib (arm 1: 50 mg sunitinib daily orally for 28 days followed by 14 days off drug; and arm 2: 37.5 mg sunitinib administered daily continuously). RESULTS: Of 73 patients enrolled, 36 patients were randomly allocated to the noncontinuous treatment arm (arm 1) and 37 patients were randomly allocated to the continuous treatment arm (arm 2). The mean age was 58.8 and 58.5 years, respectively. We observed six responders (complete response + partial response) in arm 1 (16.7%) and 2 responders in arm 2 (5.4%). The median progression-free survival (arm 1: 4.8 [2.9-8.1] months; arm 2: 2.9 [2.9-5.1] months) and the median overall survival (arm 1: 13.6 [7.0-23.2] months; arm 2: 13.7 [8.4-25.6] months) revealed no significant difference. Adverse events included fatigue as well as cardiovascular, gastrointestinal and abdominal symptoms, hematologic and hepatic laboratory abnormalities. Pattern and frequency of adverse events revealed no substantial differences between both treatment groups. CONCLUSIONS: Sunitinib treatment is feasible and moderately active in relapsed platinum-resistant ovarian cancer. The noncontinuous treatment schedule should be chosen for further studies in ovarian cancer.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Resistencia a Antineoplásicos , Indoles/administración & dosificación , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Quísticas, Mucinosas y Serosas/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Pirroles/administración & dosificación , Inhibidores de la Angiogénesis/efectos adversos , Supervivencia sin Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Indoles/efectos adversos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Neoplasias Quísticas, Mucinosas y Serosas/mortalidad , Neoplasias Ováricas/mortalidad , Compuestos de Platino/farmacología , Modelos de Riesgos Proporcionales , Pirroles/efectos adversos , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Sunitinib
2.
Data Brief ; 22: 826-829, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30766902

RESUMEN

We compiled modern and fossil relative abundance of coccolithophore species Florisphaera profunda from published and unpublished datasets, along with ocean environmental variable data from satellite remote sensing and physical measurements. The database includes relative abundances of F. profunda in sediment trap (n = 26) and core-top (n = 1258), and sediment core samples (n = 104). Downcore data covers the Last Glacial Maximum (n = 94, 24-19 ka) or the Mid-to-Late Holocene (n = 77, <6 ka). This database allows studying modern and past biogeography of F. profunda as a response to changing ocean and climate conditions, "Quantitative reconstruction of primary productivity in low latitudes during the last glacial maximum and the mid-to-late Holocene from a global Florisphaera. profunda calibration dataset" (Hernández-Almeida et al., 2018).

3.
J Leukoc Biol ; 63(1): 101-7, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9469479

RESUMEN

Interleukin-10 (IL-10) and tumor necrosis factor (TNF) exert key roles in some acute and chronic inflammatory diseases. In this study we investigated (1) the potency of different cAMP-elevating agents in enhancing IL-10 synthesis, (2) the involvement of protein kinase A in this enhancement, and (3) the mutual dependence of cAMP-enhanced IL-10 formation and cAMP-suppressed TNF synthesis. Rolipram, a specific phosphodiesterase inhibitor and cicaprost, a prostacyclin analogue, were applied as cAMP-elevating agents. The stable cAMP antagonist (Rp)-cAMPS was used to abrogate activation of protein kinase A. Human peripheral blood mononuclear cells were stimulated with lipopolysaccharide (LPS). TNF was quantified by radioimmunoassay, IL-10 by enzyme-linked immunosorbent assay, and mRNA by reverse transcriptase-polymerase chain reaction. After LPS stimulation alone 253+/-45 pg/mL IL-10 was synthesized, which increased to 644+/-117 pg/mL in the presence of 1 microM rolipram. (Rp)-cAMPS reversed this increase of IL-10 formation. In the same samples, the LPS-stimulated production of TNF was markedly attenuated by rolipram or cicaprost. A kinetic analysis revealed a significant increase in TNF production before IL-10 formation was detectable. These results demonstrate that (1) cAMP-elevating agents enhance IL-10 synthesis and suppress TNF production; (2) these regulative functions of cAMP-elevating agents are mediated by activation of protein kinases A; (3) suppression of TNF synthesis by cAMP in the early phase is not mediated by endogenous IL-10. Taken together, rolipram and cicaprost exert a dual regulatory function by enhancing IL-10 formation and attenuating TNF synthesis.


Asunto(s)
AMP Cíclico/metabolismo , Interleucina-10/biosíntesis , Leucocitos Mononucleares/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , AMP Cíclico/análogos & derivados , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Regulación hacia Abajo , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Epoprostenol/análogos & derivados , Epoprostenol/farmacología , Ayuno , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Lipopolisacáridos/farmacología , Inhibidores de Fosfodiesterasa/farmacología , Pirrolidinonas/farmacología , ARN Mensajero/genética , Rolipram , Factor de Necrosis Tumoral alfa/genética , Regulación hacia Arriba
4.
Neuroscience ; 125(4): 1009-17, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15120860

RESUMEN

Alzheimer's disease is characterized by amyloid peptide formation and deposition, neurofibrillary tangles, central cholinergic dysfunction, and dementia; however, the relationship between these parameters is not well understood. We studied the effect of amyloid peptide formation and deposition on central cholinergic function in knock-in mice carrying the human amyloid precursor protein (APP) gene with the Swedish/London double mutation (APP-SL mice) which were crossbred with transgenic mice overexpressing normal (PS1wt) or mutated (M146L; PS1mut) human presenilin-1. APP-SLxPS1mut mice had increased levels of Abeta peptides at 10 months of age and amyloid plaques at 14 months of age while APP-SLxPS1wt mice did not have increased peptide levels and did not develop amyloid plaques. We used microdialysis in 15-27 months old mice to compare hippocampal acetylcholine (ACh) levels in the two mouse lines and found that extracellular ACh levels were slightly but significantly reduced in the APP-SLxPS1mut mice (-26%; P=0.044). Exploratory activity in the open field increased hippocampal ACh release by two-fold in both mouse lines; total and relative increases were not significantly different for the two strains under study. Similarly, infusion of scopolamine (1 microM) increased hippocampal ACh release to a similar extent (3-5-fold) in both groups. High-affinity choline uptake, a measure of the ACh turnover rate, was identical in both mouse lines. Neurons expressing choline acetyltransferase were increased in the septum of APP-SLxPS1mut mice (+26%; P=0.046). We conclude that amyloid peptide production causes a small decrease of extracellular ACh levels. The deposition of amyloid plaques, however, does not impair stimulated ACh release and proceeds without major changes of central cholinergic function.


Asunto(s)
Acetilcolina/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/genética , Encéfalo/patología , Proteínas de la Membrana/genética , Acetilcolina/análisis , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Encéfalo/efectos de los fármacos , Modelos Animales de Enfermedad , Líquido Extracelular/química , Humanos , Ratones , Ratones Transgénicos , Microdiálisis , Antagonistas Muscarínicos/farmacología , Mutación , Neuronas/metabolismo , Placa Amiloide/patología , Presenilina-1 , Escopolamina/farmacología
5.
Exp Oncol ; 35(3): 168-73, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24084453

RESUMEN

AIM: Failure of platinum chemotherapy is an unresolved issue in ovarian cancer. Targeted therapy has been added to the treatment options in solid cancers. Alvocidib is a cyclin dependent kinase inhibitor. MATERIALS AND METHODS: This study evaluated the effects of alvocidib together with carboplatin on ovarian cancer cells (BG-1 and Skov-3) in vitro applying proliferation assays, cell cycle distribution analyses, apoptosis induction assays, and drug accumulation assay. RESULTS: Proliferation of both cell lines was inhibited by carboplatin and alvocidib. The interaction index revealed drug synergism at distinct drug concentrations. Cell cycle distribution was altered. Alvocidib induced apoptosis in Skov-3 cells, and necrosis in BG-1 cells. Rhodamine accumulation was increased by alvocidib or both compounds together. CONCLUSION: These data provide evidence for antiproliferative effects of alvocidib on human ovarian cancer cells in vitro associated with changes in cell cycle distribution, the induction of apoptosis, and modulation of intracellular drug accumulation. Alvocidib and carboplatin showed some cooperative activity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carboplatino/administración & dosificación , Flavonoides/administración & dosificación , Neoplasias Ováricas/metabolismo , Piperidinas/administración & dosificación , Apoptosis/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular Tumoral , Sinergismo Farmacológico , Femenino , Humanos
6.
Breast Cancer Res Treat ; 25(1): 37-46, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8390871

RESUMEN

Gonadotropin-releasing hormone analogs (GnRH-A) have been added to the armentarium in the therapy of hormone-dependent breast cancer in premenopausal women. The effect of chronic GnRH-A-treatment in premenopausal women is based on the suppression of the hypothalamus-pituitary-ovarian axis and the reduction of sex-steroid serum levels. In addition, a number of experimental and clinical data have been accumulated indicating a direct action of GnRH-A on breast cancer cells and tissue. In this study we analyzed 235 human breast cancer biopsies for specific GnRH-A-binding. We demonstrate high affinity GnRH-A binding sites in human breast cancer tissues. The evaluation of clinical data showed no correlation of the level of GnRH-A-binding with classical tumor parameters.


Asunto(s)
Neoplasias de la Mama/metabolismo , Buserelina/metabolismo , Receptores LHRH/metabolismo , Secuencia de Aminoácidos , Animales , Unión Competitiva/fisiología , Biopsia , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/patología , Femenino , Humanos , Datos de Secuencia Molecular , Ratas , Ratas Sprague-Dawley , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Fase S/fisiología
7.
J Biol Chem ; 272(23): 14505-8, 1997 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-9169406

RESUMEN

Most cases of early-onset familial Alzheimer's disease are caused by mutations in the presenilin genes. Presenilin-1 (PS1) is subject to proteolytic cleavage resulting in the accumulation of N- and C-terminal fragments. In this report, we show that the proteolytic cleavage of PS1 is developmentally regulated in the brain. Low levels of full-length PS1 and higher levels of 30-kDa N-terminal and 20-kDa C-terminal fragments are identified at all developmental stages in the rat brain. However, in the adult brain, additional 36-kDa N-terminal and 14-kDa C-terminal fragments appear and become major PS1 species. Alternative N-terminal PS1 fragments also appear in the adult human brain, but are more heterogenous than in the rat brain. The alternative PS1 fragments are not detected at significant levels in rat or human peripheral tissues that express PS1. The alternative cleavage of PS1 is also detected in primary cultures of rat hippocampal neurons, but not in astrocytes, and is induced by neuronal differentiation. Furthermore, alternative PS1 cleavage is detected in rat PC12 cells and human neuroblastoma SH-SY5Y cells following induction of neuronal differentiation. These results suggest that an alternative pathway of PS1 proteolytic processing is induced in the brain by neuronal differentiation. PS1 may therefore play an important role in brain development and neuronal function, which may relate to the brain-specific pathological effects of PS1 mutations.


Asunto(s)
Encéfalo/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de la Membrana/biosíntesis , Neuronas/metabolismo , Envejecimiento/metabolismo , Animales , Encéfalo/citología , Encéfalo/crecimiento & desarrollo , Diferenciación Celular , Línea Celular , Células Cultivadas , Cerebelo/metabolismo , Corteza Cerebral/embriología , Corteza Cerebral/metabolismo , Feto , Hipocampo/metabolismo , Humanos , Proteínas de la Membrana/química , Peso Molecular , Neuronas/citología , Especificidad de Órganos , Células PC12 , Fragmentos de Péptidos/química , Presenilina-1 , Ratas , Ratas Sprague-Dawley
8.
Res Immunol ; 149(2): 139-50, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9628395

RESUMEN

Nitric oxide (NO) and tumour necrosis factor (TNF) are essential mediators in a number of biological processes, including the immune response. TNF stimulates NO production via expression of inducible NO synthase (iNOS), with L-arginine being the only substrate. Previously, we demonstrated that, inversely, NO inhibits lipopolysaccharide (LPS)-induced TNF synthesis. We have now investigated whether this reduction of TNF bioactivity is also reflected at the level of TNF mRNA in the murine macrophage cell line RAW 264.7. TNF mRNA was quantified by Northern analysis using an alpha[33P]dCTP-labelled probe. Cells stimulated with 10 microg/ml LPS in the absence of L-arginine, in order to prevent endogenous NO formation, contained more TNF mRNA than cells supplied with 1 mM L-arginine at 14 h and 20 h after stimulation. By contrast, no difference was observed at 4 h. This time course is compatible with the involvement of iNOS. The half-life of TNF mRNA in the presence of NO was roughly half that observed under L-arginine-free conditions (41 min versus 77 min, respectively). L-citrulline (1 mM), which has been shown to be recycled in RAW 264.7 cells to L-arginine, completely restored attenuation of TNF bioactivity and TNF message to control levels obtained with 1 mM L-arginine. Together, these findings suggest that endogenous NO regulates TNF mRNA, mainly by reducing its half-life. In addition, a distinct additional band (approximately 1.4 kb) hybridizing with the TNF probe was consistently observed in non-stimulated cells. This may correspond to TNF mRNA specifically hydrolysed at the AU-rich region, possibly reflecting another control point for TNF expression.


Asunto(s)
Regulación hacia Abajo , Óxido Nítrico/metabolismo , ARN Mensajero/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , Animales , Arginina/metabolismo , Arginina/farmacología , Northern Blotting , Línea Celular , Citrulina/metabolismo , Citrulina/farmacología , Dactinomicina/farmacología , Cinética , Lipopolisacáridos/farmacología , Macrófagos , Ratones , Óxido Nítrico/inmunología , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , ARN Mensajero/genética , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
9.
Arterioscler Thromb Vasc Biol ; 19(1): 59-66, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9888867

RESUMEN

Dietary omega-3 fatty acids retard coronary atherosclerosis. Previously, we demonstrated that dietary omega-3 fatty acids reduce platelet-derived growth factor (PDGF)-A and PDGF-B mRNA levels in unstimulated, human mononuclear cells (MNCs). In a randomized, investigator-blinded intervention trial, we have now compared the effect of ingestion of 7 g/d omega-3, omega-6, or omega-9 fatty acids for 4 weeks versus no dietary intervention on PDGF-A, PDGF-B, heparin-bound epidermal growth factor (HB-EGF), monocyte chemoattractant protein-1 (MCP-1), and interleukin-10 gene expression in unstimulated MNCs and in monocytes that were adherence-activated ex vivo in a total of 28 volunteers. In unstimulated MNCs, mRNA steady-state levels of PDGF-A, PDGF-B, and MCP-1 were reduced by 25+/-10%, 31+/-13%, and 40+/-14%, respectively, after omega-3 fatty acid ingestion, as assessed by quantitative polymerase chain reaction (all P<0.05). In monocytes that were adherence-activated ex vivo for 4 and 20 hours, mRNA steady-state levels of PDGF-A, PDGF-B, and MCP-1 were reduced by 25+/-13%, 20+/-15%, and 30+/-8%, respectively (all P<0.05). Interleukin-10 and HB-EGF mRNA steady-state levels were not influenced by omega-3 fatty acid ingestion. Expression of all respective mRNAs in control volunteers or in those ingesting omega-6 or omega-9 fatty acids were not altered. We conclude that human gene expression for PDGF-A, PDGF-B, and MCP-1, factors thought relevant to atherosclerosis, is constitutive, is constant, and can be reduced only by dietary omega-3 fatty acids in unstimulated and adherence-activated monocytes.


Asunto(s)
Citocinas/genética , Grasas Insaturadas en la Dieta/farmacología , Ácidos Grasos Insaturados/farmacología , Expresión Génica , Sustancias de Crecimiento/genética , Monocitos/metabolismo , Adulto , Células Cultivadas , Quimiocina CCL2/genética , Grasas Insaturadas en la Dieta/administración & dosificación , Factor de Crecimiento Epidérmico/genética , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Omega-6 , Ácidos Grasos Insaturados/administración & dosificación , Factor de Crecimiento Similar a EGF de Unión a Heparina , Humanos , Péptidos y Proteínas de Señalización Intercelular , Interleucina-10/genética , Masculino , Factor de Crecimiento Derivado de Plaquetas/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-sis , ARN Mensajero/análisis , ARN Mensajero/metabolismo
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