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1.
Nat Commun ; 15(1): 4690, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824132

RESUMO

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.


Assuntos
Algoritmos , Aprendizado Profundo , Humanos , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Ensaios Clínicos como Assunto , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/diagnóstico , Masculino , Feminino , Seleção de Pacientes , Neoplasias Urológicas/patologia , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/genética
2.
N Engl J Med ; 389(21): 1961-1971, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37870920

RESUMO

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.).


Assuntos
Anticorpos Monoclonais Humanizados , Antineoplásicos , Carcinoma de Células de Transição , Receptores de Fatores de Crescimento de Fibroblastos , Neoplasias da Bexiga Urinária , Adulto , Humanos , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Docetaxel/efeitos adversos , Docetaxel/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico
3.
Cannabis Cannabinoid Res ; 6(4): 315-326, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33998890

RESUMO

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.


Assuntos
Barreira Hematoencefálica , Células Endoteliais , Barreira Hematoencefálica/metabolismo , Canabinoides , Células Endoteliais/metabolismo , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Br J Pharmacol ; 177(19): 4330-4352, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32608035

RESUMO

Embase and PubMed were systematically searched for articles addressing the neuroprotective properties of phytocannabinoids, apart from cannabidiol and Δ9 -tetrahydrocannabinol, including Δ9 -tetrahydrocannabinolic acid, Δ9 -tetrahydrocannabivarin, cannabidiolic acid, cannabidivarin, cannabichromene, cannabichromenic acid, cannabichromevarin, cannabigerol, cannabigerolic acid, cannabigerivarin, cannabigerovarinic acid, cannabichromevarinic acid, cannabidivarinic acid, and cannabinol. Out of 2,341 studies, 31 articles met inclusion criteria. Cannabigerol (range 5 to 20 mg·kg-1 ) and cannabidivarin (range 0.2 to 400 mg·kg-1 ) displayed efficacy in models of Huntington's disease and epilepsy. Cannabichromene (10-75 mg·kg-1 ), Δ9 -tetrahydrocannabinolic acid (20 mg·kg-1 ), and tetrahydrocannabivarin (range 0.025-2.5 mg·kg-1 ) showed promise in models of seizure and hypomobility, Huntington's and Parkinson's disease. Limited mechanistic data showed cannabigerol, its derivatives VCE.003 and VCE.003.2, and Δ9 -tetrahydrocannabinolic acid mediated some of their effects through PPAR-γ, but no other receptors were probed. Further studies with these phytocannabinoids, and their combinations, are warranted across a range of neurodegenerative disorders.


Assuntos
Canabidiol , Doença de Huntington , Canabidiol/farmacologia , Dronabinol , Humanos , Convulsões
5.
Front Cell Neurosci ; 13: 230, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244605

RESUMO

Structural alterations and breakdown of the blood brain barrier (BBB) is often a primary or secondary consequence of disease, resulting in brain oedema and the transport of unwanted substances into the brain. It is critical that effective in vitro models are developed to model the in vivo environment to aid in clinically relevant research, especially regarding drug screening and permeability studies. Our novel model uses only primary human cells and includes four of the key cells of the BBB: astrocytes, pericytes, brain microvascular endothelial cells (HBMEC) and neurons. We show that using a larger membrane pore size (3.0 µM) there is an improved connection between the endothelial cells, astrocytes and pericytes. Compared to a two and three cell model, we show that when neurons are added to HBMECs, astrocytes and pericytes, BBB integrity was more sensitive to oxygen-glucose deprivation evidenced by increased permeability and markers of cell damage. Our data also show that a four cell model responds faster to the barrier tightening effects of glucocorticoid dexamethasone, when compared to a two cell and three cell model. These data highlight the important role that neurons play in response to ischaemia, particularly how they contribute to BBB maintenance and breakdown. We consider that this model is more representative of the interactions at the neurovascular unit than other transwell models and is a useful method to study BBB physiology.

6.
Front Behav Neurosci ; 12: 269, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30534062

RESUMO

The euphoric feeling described after running is, at least in part, due to increased circulating endocannabinoids (eCBs). eCBs are lipid signaling molecules involved in reward, appetite, mood, memory and neuroprotection. The aim of this study was to investigate whether activities other than running can increase circulating eCBs. Nine healthy female volunteers (mean 61 years) were recruited from a local choir. Circulating eCBs, haemodynamics, mood and hunger ratings were measured before and immediately after 30 min of dance, reading, singing or cycling in a fasted state. Singing increased plasma levels of anandamide (AEA) by 42% (P < 0.05), palmitoylethanolamine (PEA) by 53% (P < 0.01) and oleoylethanolamine (OEA) by 34% (P < 0.05) and improved positive mood and emotions (P < 0.01), without affecting hunger scores. Dancing did not affect eCB levels or hunger ratings, but decreased negative mood and emotions (P < 0.01). Cycling increased OEA levels by 26% (P < 0.05) and tended to decrease how hungry volunteers felt, without affecting mood. Reading increased OEA levels by 28% (P < 0.01) and increased the desire to eat. Plasma AEA levels were positively correlated with how full participants felt (P < 0.05). Plasma OEA levels were positively correlated with positive mood and emotions (P < 0.01). All three ethanolamines were positively correlated with heart rate (HR; P < 0.0001). These data suggest that activities other than running can increase plasma eCBs associated with changes in mood or appetite. Increases in eCBs may underlie the rewarding and pleasurable effects of singing and exercise and ultimately some of the long-term beneficial effects on mental health, cognition and memory.

7.
Front Pharmacol ; 9: 1365, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30534073

RESUMO

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.

8.
Br J Haematol ; 160(4): 538-46, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23278590

RESUMO

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.


Assuntos
Benzoatos/administração & dosagem , Hidrazinas/administração & dosagem , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Pirazóis/administração & dosagem , Adulto , Idoso , Benzoatos/efeitos adversos , Doença Crônica , Método Duplo-Cego , Esquema de Medicação , Feminino , Hematínicos , Humanos , Hidrazinas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Pirazóis/efeitos adversos , Resultado do Tratamento , Adulto Jovem
9.
Lancet ; 377(9763): 393-402, 2011 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-20739054

RESUMO

BACKGROUND: Eltrombopag is an oral thrombopoietin receptor agonist for the treatment of thrombocytopenia. We aimed to compare the response to once daily eltrombopag versus placebo in patients with chronic immune thrombocytopenia during a 6-month period. METHODS: We undertook a phase 3, double-blind, placebo-controlled study in adults with previously treated immune thrombocytopenia of more than 6 months' duration who had baseline platelet counts lower than 30,000 per µL. Patients were randomly allocated (in a 2:1 ratio) treatment with local standard of care plus 50 mg eltrombopag or matching placebo once daily for 6 months. Randomisation was done centrally with a computer-generated randomisation schedule and was stratified by baseline platelet count (≤ 15,000 per µL), use of treatment for immune thrombocytopenia, and splenectomy status. Patients, investigators, and those assessing data were masked to allocation. Dose modifications were made on the basis of platelet response. Patients were assessed for response to treatment (defined as a platelet count of 50,000-400,000 per µL) weekly during the first 6 weeks and at least once every 4 weeks thereafter; the primary endpoint was the odds of response to eltrombopag versus placebo. Analysis was by intention to treat. This study is registered at ClinicalTrials.gov, number NCT00370331. FINDINGS: Between Nov 22, 2006, and July 31, 2007, 197 patients were randomly allocated to treatment groups and were included in the intention-to-treat analysis (135 eltrombopag, 62 placebo). 106 (79%) patients in the eltrombopag group responded to treatment at least once during the study, compared with 17 (28%) patients in the placebo group. The odds of responding were greater in patients in the eltrombopag group compared with those in the placebo group throughout the 6-month treatment period (odds ratio 8·2, 99% CI 3·59-18·73; p<0·0001). 37 (59%) patients receiving eltrombopag reduced concomitant treatment versus ten (32%) patients receiving placebo (p=0·016). 24 (18%) patients receiving eltrombopag needed rescue treatment compared with 25 (40%) patients receiving placebo (p=0·001). Three (2%) patients receiving eltrombopag had thromboembolic events compared with none in patients on placebo. Nine (7%) eltrombopag-treated patients and two (3%) in the placebo group had mild increases in alanine aminotransferase concentration, and five (4%) eltrombopag-treated patients (vs none allocated to placebo) had increases in total bilirubin. Four (7%) patients taking placebo had serious bleeding events, compared with one (<1%) patient treated with eltrombopag. INTERPRETATION: Eltrombopag is effective for management of chronic immune thrombocytopenia, and could be particularly beneficial for patients who have not responded to splenectomy or previous treatment. These benefits should be balanced with the potential risks associated with eltrombopag treatment. FUNDING: GlaxoSmithKline.


Assuntos
Benzoatos/uso terapêutico , Hidrazinas/uso terapêutico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Pirazóis/uso terapêutico , Receptores de Trombopoetina/agonistas , Adulto , Doença Crônica , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/cirurgia , Esplenectomia
10.
N Engl J Med ; 357(22): 2237-47, 2007 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-18046028

RESUMO

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.)


Assuntos
Benzoatos/administração & dosagem , Hidrazinas/administração & dosagem , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Pirazóis/administração & dosagem , Receptores de Trombopoetina/agonistas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzoatos/efeitos adversos , Benzoatos/uso terapêutico , Doença Crônica , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Humanos , Hidrazinas/efeitos adversos , Hidrazinas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/sangue , Pirazóis/efeitos adversos , Pirazóis/uso terapêutico , Qualidade de Vida , Recidiva , Trombopoetina/análise
11.
Exp Cell Res ; 312(1): 5-15, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16259978

RESUMO

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.


Assuntos
Apoptose , Fagocitose , Proteínas Serina-Treonina Quinases/fisiologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Actinas/metabolismo , Amidas/farmacologia , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Células COS , Inibidores de Caspase , Caspases/metabolismo , Membrana Celular/metabolismo , Chlorocebus aethiops , Fragmentação do DNA , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular , Toxinas Marinhas/farmacologia , Contração Muscular , Miosinas/metabolismo , Células PC12 , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Transporte Proteico , Piridinas/farmacologia , RNA Interferente Pequeno/farmacologia , Ratos , Tiazóis/farmacologia , Tiazolidinas , Quinases Associadas a rho
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