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1.
Nat Commun ; 15(1): 4690, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824132

RESUMEN

Accurate identification of genetic alterations in tumors, such as Fibroblast Growth Factor Receptor, is crucial for treating with targeted therapies; however, molecular testing can delay patient care due to the time and tissue required. Successful development, validation, and deployment of an AI-based, biomarker-detection algorithm could reduce screening cost and accelerate patient recruitment. Here, we develop a deep-learning algorithm using >3000 H&E-stained whole slide images from patients with advanced urothelial cancers, optimized for high sensitivity to avoid ruling out trial-eligible patients. The algorithm is validated on a dataset of 350 patients, achieving an area under the curve of 0.75, specificity of 31.8% at 88.7% sensitivity, and projected 28.7% reduction in molecular testing. We successfully deploy the system in a non-interventional study comprising 89 global study clinical sites and demonstrate its potential to prioritize/deprioritize molecular testing resources and provide substantial cost savings in the drug development and clinical settings.


Asunto(s)
Algoritmos , Aprendizaje Profundo , Humanos , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Ensayos Clínicos como Asunto , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/diagnóstico , Masculino , Femenino , Selección de Paciente , Neoplasias Urológicas/patología , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/genética
2.
N Engl J Med ; 389(21): 1961-1971, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37870920

RESUMEN

BACKGROUND: Erdafitinib is a pan-fibroblast growth factor receptor (FGFR) inhibitor approved for the treatment of locally advanced or metastatic urothelial carcinoma in adults with susceptible FGFR3/2 alterations who have progression after platinum-containing chemotherapy. The effects of erdafitinib in patients with FGFR-altered metastatic urothelial carcinoma who have progression during or after treatment with checkpoint inhibitors (anti-programmed cell death protein 1 [PD-1] or anti-programmed death ligand 1 [PD-L1] agents) are unclear. METHODS: We conducted a global phase 3 trial of erdafitinib as compared with chemotherapy in patients with metastatic urothelial carcinoma with susceptible FGFR3/2 alterations who had progression after one or two previous treatments that included an anti-PD-1 or anti-PD-L1. Patients were randomly assigned in a 1:1 ratio to receive erdafitinib or the investigator's choice of chemotherapy (docetaxel or vinflunine). The primary end point was overall survival. RESULTS: A total of 266 patients underwent randomization: 136 to the erdafitinib group and 130 to the chemotherapy group. The median follow-up was 15.9 months. The median overall survival was significantly longer with erdafitinib than with chemotherapy (12.1 months vs. 7.8 months; hazard ratio for death, 0.64; 95% confidence interval [CI], 0.47 to 0.88; P = 0.005). The median progression-free survival was also longer with erdafitinib than with chemotherapy (5.6 months vs. 2.7 months; hazard ratio for progression or death, 0.58; 95% CI, 0.44 to 0.78; P<0.001). The incidence of grade 3 or 4 treatment-related adverse events was similar in the two groups (45.9% in the erdafitinib group and 46.4% in the chemotherapy group). Treatment-related adverse events that led to death were less common with erdafitinib than with chemotherapy (in 0.7% vs. 5.4% of patients). CONCLUSIONS: Erdafitinib therapy resulted in significantly longer overall survival than chemotherapy among patients with metastatic urothelial carcinoma and FGFR alterations after previous anti-PD-1 or anti-PD-L1 treatment. (Funded by Janssen Research and Development; THOR ClinicalTrials.gov number, NCT03390504.).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antineoplásicos , Carcinoma de Células Transicionales , Receptores de Factores de Crecimiento de Fibroblastos , Neoplasias de la Vejiga Urinaria , Adulto , Humanos , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/mortalidad , Carcinoma de Células Transicionales/patología , Docetaxel/efectos adversos , Docetaxel/uso terapéutico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Receptores de Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico
3.
Prostate Cancer Prostatic Dis ; 25(2): 219-228, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34257408

RESUMEN

BACKGROUND: The safety and immunogenicity of JNJ-64041809 (JNJ-809), a live-attenuated, double-deleted Listeria monocytogenes (LADD Lm)-based immunotherapy targeting 4 relevant prostate cancer antigens, was evaluated in a phase 1 study in patients with metastatic castration-resistant prostate cancer (mCRPC). METHODS: Men with progressive mCRPC who had received ≥2 prior approved therapies were enrolled. Primary study objectives were to determine the recommended phase 2 dose (RP2D) and to evaluate the safety and immunogenicity of JNJ-809. RESULTS: A total of 26 patients received JNJ-809 (1 × 108 CFU (n = 6); 1 × 109 CFU (n = 20)). No dose-limiting toxicities were reported, and 1 × 109 CFU was selected as the RP2D. The most common adverse events (AEs) reported were chills (92%), pyrexia (81%), and fatigue (62%). The most frequent grade ≥3 AEs were lymphopenia (27%) and hypertension (23%). Serious AEs were reported in 27% of patients including 1 patient with grade 3 intestinal obstruction. JNJ-809 transiently induced peripheral cytokines, including interferon-γ, interleukin-10, and tumor necrosis factor-α. Of the 7 patients evaluable for T cell responses at the 1 × 109 CFU dose, evidence of post-treatment antigenic responses were observed in 6 to the Listeria antigen listeriolysin O and in 5 to ≥1 of the 4 encoded tumor antigens. Best overall response was stable disease in 13/25 response-evaluable patients. The study was terminated early as data collected were considered sufficient to evaluate safety and immunogenicity. CONCLUSIONS: JNJ-809 has manageable safety consistent with other LADD Lm-based therapies. Limited antigen-specific immune responses were observed, which did not translate into objective clinical responses.


Asunto(s)
Listeria monocytogenes , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Inmunoterapia/efectos adversos , Listeria monocytogenes/genética , Masculino , Neoplasias de la Próstata Resistentes a la Castración/patología
4.
JTO Clin Res Rep ; 2(2): 100103, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34589981

RESUMEN

INTRODUCTION: JNJ-64041757 (JNJ-757) is a live, attenuated, double-deleted Listeria monocytogenes-based immunotherapy expressing human mesothelin. JNJ-757 was evaluated in patients with advanced NSCLC as monotherapy (phase 1) and in combination with nivolumab (phase 1b/2). METHODS: Patients with stage IIIB/IV NSCLC who had received previous therapy were treated with JNJ-757 (1 × 108 or 1 × 109 colony-forming units [CFUs]) alone (NCT02592967) or JNJ-757 (1 × 109 CFU) plus intravenous nivolumab 240 mg (NCT03371381). Study objectives included the assessment of immunogenicity, safety, and efficacy. RESULTS: In the monotherapy study, 18 patients (median age 63.5 y; women 61%) were treated with JNJ-757 (1 × 108 or 1 × 109 CFU) with a median duration of 1.4 months (range: 0-29). The most common adverse events (AEs) were pyrexia (72%) and chills (61%), which were usually mild and resolved within 48 hours. Peripheral proinflammatory cytokines and lymphocyte activation were induced posttreatment with transient mesothelin-specific T-cell responses in 10 of 13 biomarker-evaluable patients. With monotherapy, four of 18 response-evaluable patients had stable disease of 16 or more weeks, including one patient with a reduction in target lesions. In the combination study, 12 patients were enrolled (median age 63.5 y; women 33%). The most common AEs with combination therapy were pyrexia (67%) and chills (58%); six patients had grade 3 AEs or greater, including two cases of treatment-related fatal pneumonitis. The best overall response for the combination was stable disease in four of nine response-evaluable patients. CONCLUSIONS: As monotherapy, JNJ-757 was immunogenic and tolerable, with mild infusion-related fever and chills. The limited efficacy of JNJ-757, alone or with nivolumab, did not warrant further investigation of the combination.

5.
Cannabis Cannabinoid Res ; 6(4): 315-326, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33998890

RESUMEN

Background and Objectives: Preclinical studies have shown cannabidiol is protective in models of ischemic stroke. Based on results from our recent systematic review, we investigated the effects of two promising neuroprotective phytocannabinoids, cannabigerol (CBG) and cannabidivarin (CBDV), on cells of the blood-brain barrier (BBB), namely human brain microvascular endothelial cells (HBMECs), pericytes, and astrocytes. Experimental Approach: Cultures were subjected to oxygen-glucose deprivation (OGD) protocol to model ischemic stroke and cell culture medium was assessed for cytokines and adhesion molecules post-OGD. Astrocyte cell lysates were also analyzed for DNA damage markers. Antagonist studies were conducted where appropriate to study receptor mechanisms. Results: In astrocytes CBG and CBDV attenuated levels of interleukin-6 (IL-6) and lactate dehydrogenase (LDH), whereas CBDV (10 nM-10 µM) also decreased vascular endothelial growth factor (VEGF) secretion. CBDV (300 nM-10 µM) attenuated levels of monocyte chemoattractant protein (MCP)-1 in HBMECs. In astrocytes, CBG decreased levels of DNA damage proteins, including p53, whereas CBDV increased levels of DNA damage markers. Antagonists for CB1, CB2, PPAR-γ, PPAR-α, 5-HT1A, and TRPV1 had no effect on CBG (3 µM) or CBDV (1 µM)-mediated decreases in LDH in astrocytes. GPR55 and GPR18 were partially implicated in the effects of CBDV, but no molecular target was identified for CBG. Conclusions: We show that CBG and CBDV were protective against OG mediated injury in three different cells that constitute the BBB, modulating different hallmarks of ischemic stroke pathophysiology. These data enhance our understanding of the protective effects of CBG and CBDV and warrant further investigation into these compounds in ischemic stroke. Future studies should identify other possible neuroprotective effects of CBG and CBDV and their corresponding mechanisms of action.


Asunto(s)
Barrera Hematoencefálica , Células Endoteliales , Barrera Hematoencefálica/metabolismo , Cannabinoides , Células Endoteliales/metabolismo , Humanos , Factor A de Crecimiento Endotelial Vascular/metabolismo
6.
Front Pharmacol ; 9: 1365, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30534073

RESUMEN

Background: Cannabidiol is being pursued as a therapeutic treatment for multiple conditions, usually by oral delivery. Animal studies suggest oral bioavailability is low, but literature in humans is not sufficient. The aim of this review was to collate published data in this area. Methods: A systematic search of PubMed and EMBASE (including MEDLINE) was conducted to retrieve all articles reporting pharmacokinetic data of CBD in humans. Results: Of 792 articles retireved, 24 included pharmacokinetic parameters in humans. The half-life of cannabidiol was reported between 1.4 and 10.9 h after oromucosal spray, 2-5 days after chronic oral administration, 24 h after i.v., and 31 h after smoking. Bioavailability following smoking was 31% however no other studies attempted to report the absolute bioavailability of CBD following other routes in humans, despite i.v formulations being available. The area-under-the-curve and Cmax increase in dose-dependent manners and are reached quicker following smoking/inhalation compared to oral/oromucosal routes. Cmax is increased during fed states and in lipid formulations. Tmax is reached between 0 and 4 h. Conclusions: This review highlights the paucity in data and some discrepancy in the pharmacokinetics of cannabidiol, despite its widespread use in humans. Analysis and understanding of properties such as bioavailability and half-life is critical to future therapeutic success, and robust data from a variety of formulations is required.

7.
Lancet Haematol ; 2(10): e417-26, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26686043

RESUMEN

BACKGROUND: Patients with myelodysplastic syndrome or acute myeloid leukaemia who are thrombocytopenic and unable to receive disease-modifying therapy have few treatment options. Platelet transfusions provide transient benefit and are limited by alloimmunisation. Eltrombopag, an oral thrombopoietin receptor agonist, increases platelet counts and has preclinical antileukaemic activity. We aimed to assess the safety and tolerability of eltrombopag for the treatment of thrombocytopenia in adult patients with advanced myelodysplastic syndrome, secondary acute myeloid leukaemia after myelodysplastic syndrome, or de-novo acute myeloid leukaemia. METHODS: We did this multicentre, randomised, placebo-controlled, double-blind, phase 1/2 trial at 37 centres in ten countries in Europe, east Asia, and the Americas. Patients aged 18 years or older who had relapsed or refractory disease or were ineligible for standard treatments; had platelet counts of less than 30 × 10(9) platelets per L; had 10-50% bone-marrow blasts; or were platelet transfusion dependent were randomly assigned (2:1), via a telephone-based interactive voice-response system (GlaxoSmithKline Registration and Medication Ordering System) with a permuted-block randomisation schedule (block size of three), to receive once-daily eltrombopag or matching placebo dose adjusted from 50 mg to a maximum dose of 300 mg. Randomisation was stratified by presence of poor-prognosis (complex) karyotype (presence of at least three abnormalities, or chromosome 7 abnormalities, vs absence) and bone-marrow blast count (<20% vs ≥20%). Patients and study personnel were masked to treatment allocation. The primary endpoint was safety and tolerability, including adverse events, non-haematological laboratory grade 3-4 toxic effects, and changes in bone-marrow blast counts from baseline. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, number NCT00903422. FINDINGS: Between May 14, 2009, and May 9, 2013, we randomly assigned 98 patients to receive either eltrombopag (n=64) or placebo (n=34). 63 (98%) patients in the eltrombopag group and 32 (94%) patients in the placebo group had adverse events. The most common adverse events were pyrexia (27 [42%] vs 11 [32%]), nausea (20 [31%] vs 7 [21%]), diarrhoea (19 [30%] vs 6 [18%]), fatigue (16 [25%] vs 6 [18%]), decreased appetite (15 [23%] vs 5 [15%]), and pneumonia (14 [22%] vs 8 [24%]). Drug-related adverse events of grade 3 or higher were reported in six (9%) patients in the eltrombopag group and four (12%) patients in the placebo group. Increases in the proportion of peripheral blasts did not differ significantly between groups. Haemorrhage of grade 3 or higher was reported in ten (16%) patients given eltrombopag and nine (26%) patients given placebo. 21 (33%) patients receiving eltrombopag and 16 (47%) patients receiving placebo died while on treatment. No deaths in patients receiving eltrombopag and two deaths in patients receiving placebo were regarded as treatment related. Post-baseline bone-marrow examinations were done in 40 (63%) patients in the eltrombopag group and 17 (50%) patients in the placebo group. The most common reason for no examination was death before the scheduled 3 month assessment. There were no differences between median bone-marrow blast counts or proportions of peripheral blasts between groups. INTERPRETATION: Eltrombopag doses up to 300 mg daily had an acceptable safety profile in patients with advanced myelodysplastic syndrome or acute myeloid leukaemia. The role of eltrombopag in these patients warrants further investigation. FUNDING: GlaxoSmithKline.


Asunto(s)
Benzoatos/uso terapéutico , Hidrazinas/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Pirazoles/uso terapéutico , Trombocitopenia/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Humanos , Leucemia Mieloide Aguda/complicaciones , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/complicaciones , Receptores de Trombopoyetina/agonistas , Trombocitopenia/complicaciones , Resultado del Tratamiento
8.
Br J Haematol ; 160(4): 538-46, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23278590

RESUMEN

Eltrombopag is a thrombopoietin-receptor agonist that stimulates platelet production and increases platelet counts in patients with chronic immune thrombocytopenia (ITP). This open-label, single-arm study evaluated consistency of response and safety following repeated intermittent dosing of eltrombopag 50 mg daily over 3 cycles (1 cycle = up to 6 weeks on therapy followed by up to 4 weeks off therapy). The primary endpoint was proportion of patients with a response (platelet count ≥50 × 10(9) /l and ≥2× baseline) in Cycle 1 who subsequently responded in Cycle 2 or 3. Fifty-two of 65 evaluable patients (80%) responded in Cycle 1; these responding patients comprised the primary analysis population. Of these, 45/52 (87%) responded in Cycle 2 or 3 [95% confidence interval (CI), 74-94%] and 34/48 (71%; 95% CI, 56-83%) responded in both Cycles 2 and 3. Time to response was consistent, with >50% of responders responding by Day 8 in each cycle. Bleeding rates relative to baseline decreased by approximately 50% during each treatment cycle. The frequency or severity of adverse events, most commonly headache, did not increase over successive cycles. If a chronic ITP patient not requiring consistent therapy responds to short-term eltrombopag, then subsequent courses of eltrombopag, as needed, are likely to be safe and effective.


Asunto(s)
Benzoatos/administración & dosificación , Hidrazinas/administración & dosificación , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Pirazoles/administración & dosificación , Adulto , Anciano , Benzoatos/efectos adversos , Enfermedad Crónica , Método Doble Ciego , Esquema de Medicación , Femenino , Hematínicos , Humanos , Hidrazinas/efectos adversos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Pirazoles/efectos adversos , Resultado del Tratamiento , Adulto Joven
9.
BMC Med Genet ; 13: 62, 2012 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-22856873

RESUMEN

BACKGROUND: Neural tube defects (NTDs) are common birth defects (~1 in 1000 pregnancies in the US and Europe) that have complex origins, including environmental and genetic factors. A low level of maternal folate is one well-established risk factor, with maternal periconceptional folic acid supplementation reducing the occurrence of NTD pregnancies by 50-70%. Gene variants in the folate metabolic pathway (e.g., MTHFR rs1801133 (677 C > T) and MTHFD1 rs2236225 (R653Q)) have been found to increase NTD risk. We hypothesized that variants in additional folate/B12 pathway genes contribute to NTD risk. METHODS: A tagSNP approach was used to screen common variation in 82 candidate genes selected from the folate/B12 pathway and NTD mouse models. We initially genotyped polymorphisms in 320 Irish triads (NTD cases and their parents), including 301 cases and 341 Irish controls to perform case-control and family based association tests. Significantly associated polymorphisms were genotyped in a secondary set of 250 families that included 229 cases and 658 controls. The combined results for 1441 SNPs were used in a joint analysis to test for case and maternal effects. RESULTS: Nearly 70 SNPs in 30 genes were found to be associated with NTDs at the p < 0.01 level. The ten strongest association signals (p-value range: 0.0003-0.0023) were found in nine genes (MFTC, CDKN2A, ADA, PEMT, CUBN, GART, DNMT3A, MTHFD1 and T (Brachyury)) and included the known NTD risk factor MTHFD1 R653Q (rs2236225). The single strongest signal was observed in a new candidate, MFTC rs17803441 (OR = 1.61 [1.23-2.08], p = 0.0003 for the minor allele). Though nominally significant, these associations did not remain significant after correction for multiple hypothesis testing. CONCLUSIONS: To our knowledge, with respect to sample size and scope of evaluation of candidate polymorphisms, this is the largest NTD genetic association study reported to date. The scale of the study and the stringency of correction are likely to have contributed to real associations failing to survive correction. We have produced a ranked list of variants with the strongest association signals. Variants in the highest rank of associations are likely to include true associations and should be high priority candidates for further study of NTD risk.


Asunto(s)
Variación Genética , Defectos del Tubo Neural/genética , Animales , Estudios de Casos y Controles , Modelos Animales de Enfermedad , Femenino , Ácido Fólico/genética , Ácido Fólico/metabolismo , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Irlanda , Ratones , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Vitamina B 12/genética , Vitamina B 12/metabolismo
10.
PLoS One ; 6(7): e21851, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21765920

RESUMEN

One-carbon metabolism (OCM) is linked to DNA synthesis and methylation, amino acid metabolism and cell proliferation. OCM dysfunction has been associated with increased risk for various diseases, including cancer and neural tube defects. MicroRNAs (miRNAs) are ∼ 22 nt RNA regulators that have been implicated in a wide array of basic cellular processes, such as differentiation and metabolism. Accordingly, mis-regulation of miRNA expression and/or activity can underlie complex disease etiology. We examined the possibility of OCM regulation by miRNAs. Using computational miRNA target prediction methods and Monte-Carlo based statistical analyses, we identified two candidate miRNA "master regulators" (miR-22 and miR-125) and one candidate pair of "master co-regulators" (miR-344-5p/484 and miR-488) that may influence the expression of a significant number of genes involved in OCM. Interestingly, miR-22 and miR-125 are significantly up-regulated in cells grown under low-folate conditions. In a complementary analysis, we identified 15 single nucleotide polymorphisms (SNPs) that are located within predicted miRNA target sites in OCM genes. We genotyped these 15 SNPs in a population of healthy individuals (age 18-28, n =  2,506) that was previously phenotyped for various serum metabolites related to OCM. Prior to correction for multiple testing, we detected significant associations between TCblR rs9426 and methylmalonic acid (p  =  0.045), total homocysteine levels (tHcy) (p  =  0.033), serum B12 (p < 0.0001), holo transcobalamin (p < 0.0001) and total transcobalamin (p < 0.0001); and between MTHFR rs1537514 and red blood cell folate (p < 0.0001). However, upon further genetic analysis, we determined that in each case, a linked missense SNP is the more likely causative variant. Nonetheless, our Monte-Carlo based in silico simulations suggest that miRNAs could play an important role in the regulation of OCM.


Asunto(s)
Carbono/metabolismo , Biología Computacional , Genes/genética , Estudio de Asociación del Genoma Completo/métodos , MicroARNs/metabolismo , Adolescente , Adulto , Animales , Regulación de la Expresión Génica , Estudios de Asociación Genética , Humanos , Mamíferos/genética , MicroARNs/genética , Polimorfismo de Nucleótido Simple/genética , Adulto Joven
11.
N Engl J Med ; 357(22): 2237-47, 2007 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-18046028

RESUMEN

BACKGROUND: The pathogenesis of chronic idiopathic thrombocytopenic purpura (ITP) involves antibody-mediated platelet destruction and reduced platelet production. Stimulation of platelet production may be an effective treatment for this disorder. METHODS: We conducted a trial in which 118 adults with chronic ITP and platelet counts of less than 30,000 per cubic millimeter who had had relapses or whose platelet count was refractory to at least one standard treatment for ITP were randomly assigned to receive the oral thrombopoietin-receptor agonist eltrombopag (30, 50, or 75 mg daily) or placebo. The primary end point was a platelet count of 50,000 or more per cubic millimeter on day 43. RESULTS: In the eltrombopag groups receiving 30, 50, and 75 mg per day, the primary end point was achieved in 28%, 70%, and 81% of patients, respectively. In the placebo group, the end point was achieved in 11% of patients. The median platelet counts on day 43 for the groups receiving 30, 50, and 75 mg of eltrombopag were 26,000, 128,000, and 183,000 per cubic millimeter, respectively; for the placebo group the count was 16,000 per cubic millimeter. By day 15, more than 80% of patients receiving 50 or 75 mg of eltrombopag daily had an increased platelet count. Bleeding also decreased during treatment in these two groups. The incidence and severity of adverse events were similar in the placebo and eltrombopag groups. CONCLUSIONS: Eltrombopag increased platelet counts in a dose-dependent manner in patients with relapsed or refractory ITP. (ClinicalTrials.gov number, NCT00102739.)


Asunto(s)
Benzoatos/administración & dosificación , Hidrazinas/administración & dosificación , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Pirazoles/administración & dosificación , Receptores de Trombopoyetina/agonistas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Benzoatos/efectos adversos , Benzoatos/uso terapéutico , Enfermedad Crónica , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Humanos , Hidrazinas/efectos adversos , Hidrazinas/uso terapéutico , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Púrpura Trombocitopénica Idiopática/sangre , Pirazoles/efectos adversos , Pirazoles/uso terapéutico , Calidad de Vida , Recurrencia , Trombopoyetina/análisis
12.
Exp Cell Res ; 312(1): 5-15, 2006 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-16259978

RESUMEN

During the execution phase of apoptosis, a cell undergoes cytoplasmic and nuclear changes that prepare it for death and phagocytosis. The end-point of the execution phase is condensation into a single apoptotic body or fragmentation into multiple apoptotic bodies. Fragmentation is thought to facilitate phagocytosis; however, mechanisms regulating fragmentation are unknown. An isoform of Rho kinase, ROCK-I, drives membrane blebbing through its activation of actin-myosin contraction; this raises the possibility that ROCK-I may regulate other execution phase events, such as cellular fragmentation. Here, we show that COS-7 cells fragment into a number of small apoptotic bodies during apoptosis; treating with ROCK inhibitors (Y-27632 or H-1152) prevents fragmentation. Latrunculin B and blebbistatin, drugs that interfere with actin-myosin contraction, also inhibit fragmentation. During apoptosis, ROCK-I is cleaved and activated by caspases, while ROCK-II is not activated, but rather translocates to a cytoskeletal fraction. siRNA knock-down of ROCK-I but not ROCK-II inhibits fragmentation of dying cells, consistent with ROCK-I being required for apoptotic fragmentation. Finally, cells dying in the presence of the ROCK inhibitor Y-27632 are not efficiently phagocytized. These data show that ROCK plays an essential role in fragmentation and phagocytosis of apoptotic cells.


Asunto(s)
Apoptosis , Fagocitosis , Proteínas Serina-Treonina Quinasas/fisiología , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Actinas/metabolismo , Amidas/farmacología , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Células COS , Inhibidores de Caspasas , Caspasas/metabolismo , Membrana Celular/metabolismo , Chlorocebus aethiops , Fragmentación del ADN , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Péptidos y Proteínas de Señalización Intracelular , Toxinas Marinas/farmacología , Contracción Muscular , Miosinas/metabolismo , Células PC12 , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Transporte de Proteínas , Piridinas/farmacología , ARN Interferente Pequeño/farmacología , Ratas , Tiazoles/farmacología , Tiazolidinas , Quinasas Asociadas a rho
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