Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Breast Cancer Res ; 21(1): 27, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30777098

RESUMO

BACKGROUND: TNF-related apoptosis-inducing ligand (TRAIL) receptor agonists are attractive anti-tumor agents because of their capability to induce apoptosis in cancer cells by activating death receptors (DR) 4 and 5 with little toxicity against normal cells. Despite an attractive mechanism of action, previous clinical efforts to use TRAIL receptor agonists have been unsuccessful. In this study, we examined MEDI3039, a highly potent multivalent DR5 agonist, in breast cancer cell lines and in vivo models. METHODS: As in vitro model systems, we used 19 breast cancer cell lines that are categorized into four subtypes: ER+, HER2 amplified, basal A (triple-negative breast cancer) TNBC, and basal B TNBC. Cell viability was analyzed by MTS and RealTime live/dead assays. As in vivo model systems, MDA-MB231T orthotopic primary tumor growth in the mammary fat pad (MFP) and two experimental lung metastasis models were used. The effect of MEDI3039 on MFP tumors was assessed with immunohistochemical analysis. Lung metastases were analyzed with Bouin's and H&E staining. RESULTS: MEDI3039 killed multiple breast cancer cell lines, but the sensitivity varied among different subtypes. Sensitivity was basal B TNBC >> basal A TNBC > HER2 amplified > ER+ (average IC50 = 1.4, 203, 314, 403 pM, respectively). While the pattern of relative sensitivity was similar to GST-TRAIL in most cell lines, MEDI3039 was at least two orders of magnitude more potent compared with GST-TRAIL. In the MFP model, weekly treatment with 0.1 or 0.3 mg/kg MEDI3039 for 5 weeks inhibited tumor growth by 99.05% or 100% (median), respectively, compared with the control group, and extended animal survival (p = 0.08 or p = 0.0032 at 0.1 or 0.3 mg/kg, respectively). MEDI3039-induced caspase activation was confirmed in tumors grown in MFP (p < 0.05). In an experimental pulmonary metastasis model, MEDI3039 significantly suppressed outgrowth of surface (p < 0.0001) and microscopic metastases (p < 0.05). In an established lung metastasis model, MEDI3039 significantly inhibited growth of metastases (p < 0.01 in surface [> 4 mm], p < 0.01 in tumor percentage) and extended animal survival (p < 0.0001). CONCLUSION: MEDI3039 is a potent DR5 agonist in breast cancer cells in vitro and in vivo and has potential as a cancer drug in breast cancer patients, especially those with basal B TNBC.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/agonistas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Nus , Análise de Sobrevida , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Neurobiol Dis ; 132: 104582, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31445162

RESUMO

There are no approved drug therapies that can prevent or slow the progression of Parkinson's disease (PD). Accumulation and aggregation of α-synuclein protein is observed throughout the nervous system in PD. α-Synuclein is a core component of Lewy bodies and neurites that neuropathologically define PD, suggesting that α-synuclein may be a key causative agent in PD. Recent experimental data suggest that PD progression may arise due to spreading of pathological forms of extracellular α-synuclein throughout the brain via a cellular release, uptake and seeding mechanism. We have developed a high affinity α-synuclein antibody, MEDI1341, that can enter the brain, sequester extracellular α-synuclein and attenuate α-synuclein spreading in vivo. MEDI1341 binds both monomeric and aggregated forms of α-synuclein. In vitro, MEDI1341 blocks cell-to-cell transmission of pathologically relevant α-synuclein preformed fibrils (pffs). After intravenous injection into rats and cynomolgus monkeys, MEDI1341 rapidly enters the central nervous system and lowers free extracellular α-synuclein levels in the interstitial fluid (ISF) and cerebrospinal fluid (CSF) compartments. Using a novel lentiviral-based in vivo mouse model of α-synuclein spreading in the brain, we show that treatment with MEDI1341 significantly reduces α-synuclein accumulation and propagation along axons. In this same model, we demonstrate that an effector-null version of the antibody was equally as effective as one with effector function. MEDI1341 is now in Phase 1 human clinical trial testing as a novel treatment for α-synucleinopathies including PD with the aim to slow or halt disease progression.


Assuntos
Anticorpos Monoclonais/farmacologia , Encéfalo/efeitos dos fármacos , alfa-Sinucleína/antagonistas & inibidores , Animais , Especificidade de Anticorpos , Humanos , Macaca fascicularis , Camundongos , Ratos
3.
Pharm Stat ; 18(6): 688-699, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31140720

RESUMO

Linear models are generally reliable methods for analyzing tumor growth in vivo, with drug effectiveness being represented by the steepness of the regression slope. With immunotherapy, however, not all tumor growth follows a linear pattern, even after log transformation. Tumor kinetics models are mechanistic models that describe tumor proliferation and tumor killing macroscopically, through a set of differential equations. In drug combination studies, although an additional drug-drug interaction term can be added to such models, however, the drug interactions suggested by tumor kinetics models cannot be translated directly into synergistic effects. We have developed a novel statistical approach that simultaneously models tumor growth in control, monotherapy, and combination therapy groups. This approach makes it possible to test for synergistic effects directly and to compare such effects among different studies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Imunoterapia/métodos , Modelos Teóricos , Neoplasias/tratamento farmacológico , Interações Medicamentosas , Sinergismo Farmacológico , Humanos , Cinética , Modelos Lineares , Neoplasias/patologia , Resultado do Tratamento
4.
J Neurooncol ; 131(1): 185-191, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27844311

RESUMO

MEDI-575, an immunoglobulin G2κ monoclonal antibody, selectively binds to platelet-derived growth factor-α receptor (PDGFR-α) with high specificity. This multicenter, single-arm, open-label, phase II study evaluated the efficacy and safety of MEDI-575 in patients with recurrent glioblastoma. Adults with first recurrence of glioblastoma following surgery, temozolomide, and radiation received MEDI-575 25 mg/kg intravenously over 60 min every 21 days until disease progression or unacceptable toxicity. Six-month progression-free survival rate (PFS-6) was the primary end point; secondary measures included response rate, overall survival (OS), and safety/tolerability. PDGFR-α expression was evaluated by immunohistochemistry. Fifty-six patients were enrolled; median age was 56.5 years (range 23-79), 66 % were male, and 66 % were aged ≥65 years. PFS-6 was 15.4 % [90 % confidence interval (CI) 8.1-24.9]. No complete or partial responses were observed; 23 (41.1 %) patients had stable disease as best response. Median PFS was 1.4 months (90 % CI 1.4, 1.8); median OS was 9.7 months (90 % CI 6.5, 11.8). The most common treatment-related adverse events (AEs) were diarrhea (16 %), nausea (13 %), and fatigue (13 %). Twelve (21 %) patients reported grade ≥3 AEs, with hydrocephalus (n = 3), dysphagia (n = 2), and convulsion (n = 2) reported in more than 1 patient. Two patients had treatment-related Grade ≥3 AEs of decreased lymphocyte count and asthenia (n = 1 each). Seven patients (13 %) discontinued MEDI-575 owing to AEs. Labeling of PDGFRα in glioblastoma cells and tumor-associated stromal cells was highly variable, with no correlation with PFS. MEDI-575, although well tolerated, had limited clinical activity in recurrent glioblastoma.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/mortalidade , Intervalo Livre de Doença , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/mortalidade , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Resultado do Tratamento , Estados Unidos , Adulto Jovem
5.
Lancet Oncol ; 17(3): 299-308, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26858122

RESUMO

BACKGROUND: PD-L1 and CTLA-4 immune checkpoints inhibit antitumour T-cell activity. Combination treatment with the anti-PD-L1 antibody durvalumab and the anti-CTLA-4 antibody tremelimumab might provide greater antitumour activity than either drug alone. We aimed to assess durvalumab plus tremelimumab in patients with advanced squamous or non-squamous non-small cell lung cancer (NSCLC). METHODS: We did a multicentre, non-randomised, open-label, phase 1b study at five cancer centres in the USA. We enrolled immunotherapy-naive patients aged 18 years or older with confirmed locally advanced or metastatic NSCLC. We gave patients durvalumab in doses of 3 mg/kg, 10 mg/kg, 15 mg/kg, or 20 mg/kg every 4 weeks, or 10 mg/kg every 2 weeks, and tremelimumab in doses of 1 mg/kg, 3 mg/kg, or 10 mg/kg every 4 weeks for six doses then every 12 weeks for three doses. The primary endpoint of the dose-escalation phase was safety. Safety analyses were based on the as-treated population. The dose-expansion phase of the study is ongoing. This study is registered with ClinicalTrials.gov, number NCT02000947. FINDINGS: Between Oct 28, 2013, and April 1, 2015, 102 patients were enrolled into the dose-escalation phase and received treatment. At the time of this analysis (June 1, 2015), median follow-up was 18·8 weeks (IQR 11-33). The maximum tolerated dose was exceeded in the cohort receiving durvalumab 20 mg/kg every 4 weeks plus tremelimumab 3 mg/kg, with two (30%) of six patients having a dose-limiting toxicity (one grade 3 increased aspartate aminotransferase and alanine aminotransferase and one grade 4 increased lipase). The most frequent treatment-related grade 3 and 4 adverse events were diarrhoea (11 [11%]), colitis (nine [9%]), and increased lipase (eight [8%]). Discontinuations attributable to treatment-related adverse events occurred in 29 (28%) of 102 patients. Treatment-related serious adverse events occurred in 37 (36%) of 102 patients. 22 patients died during the study, and three deaths were related to treatment. The treatment-related deaths were due to complications arising from myasthenia gravis (durvalumab 10 mg/kg every 4 weeks plus tremelimumab 1 mg/kg), pericardial effusion (durvalumab 20 mg/kg every 4 weeks plus tremelimumab 1 mg/kg), and neuromuscular disorder (durvalumab 20 mg/kg every 4 weeks plus tremelimumab 3 mg/kg). Evidence of clinical activity was noted both in patients with PD-L1-positive tumours and in those with PD-L1-negative tumours. Investigator-reported confirmed objective responses were achieved by six (23%, 95% CI 9-44) of 26 patients in the combined tremelimumab 1 mg/kg cohort, comprising two (22%, 95% CI 3-60) of nine patients with PD-L1-positive tumours and four (29%, 95% CI 8-58) of 14 patients with PD-L1-negative tumours, including those with no PD-L1 staining (four [40%, 95% CI 12-74] of ten patients). INTERPRETATION: Durvalumab 20 mg/kg every 4 weeks plus tremelimumab 1 mg/kg showed a manageable tolerability profile, with antitumour activity irrespective of PD-L1 status, and was selected as the dose for phase 3 studies, which are ongoing. FUNDING: MedImmune.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
6.
Brain ; 137(Pt 2): 553-64, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24259408

RESUMO

Alzheimer's disease is characterized by the accumulation of amyloid deposits in the brain and the progressive loss of cognitive functions. Although the precise role of amyloid-ß in disease progression remains somewhat controversial, many efforts to halt or reverse disease progression have focussed on reducing its synthesis or enhancing its removal. It is believed that brain and peripheral soluble amyloid-ß are in equilibrium and it has previously been hypothesized that a reduction in peripheral amyloid-ß can lower brain amyloid-ß, thereby reducing formation of plaques predominantly composed of insoluble amyloid-ß; the so-called peripheral sink hypothesis. Here we describe the use of an amyloid-ß degrading enzyme, the endogenous metallopeptidase neprilysin, which is fused to albumin to extend plasma half-life and has been engineered to confer increased amyloid-ß degradation activity. We used this molecule to investigate the effect of degradation of peripheral amyloid-ß on amyloid-ß levels in the brain and cerebrospinal fluid after repeated intravenous dosing for up to 4 months in Tg2576 transgenic mice, and 1 month in rats and monkeys. This molecule proved highly effective at degradation of amyloid-ß in the periphery but did not alter brain or cerebrospinal fluid amyloid-ß levels, suggesting that the peripheral sink hypothesis is not valid and is the first time that this has been demonstrated in non-human primates.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Neprilisina/administração & dosagem , Animais , Feminino , Humanos , Injeções Intravenosas , Macaca fascicularis , Masculino , Camundongos , Camundongos Transgênicos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
7.
J Food Sci Technol ; 52(9): 5418-26, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26344958

RESUMO

The availability of fruit like litchi has been limited by variability in yield, alternate bearing, seasonal differences and most commonly post harvest problems. The litchi fruit has a very short shelf-life during which red color turns brown which greatly affects the appeal to consumer although not the unique flavor. This review article focuses on the post harvest problems especially browning of litchi. The pericarp of litchi is also sensitive to desiccation and turns brown and brittle once moisture is reduced to half. A large number of approaches have been tried to solve this problem starting from hydro-cooling to gamma irradiation but single approach could not suffice for all. In modern era, the logical base of controlling browning is either to control the responsible enzyme or remove the undesirable product of enzyme catalyzed reaction. Thus enzyme technology with good postharvest practice can definitely solve this problem.

8.
Lancet ; 379(9832): 2162-72, 2012 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-22682464

RESUMO

BACKGROUND: Preterm birth is the second largest direct cause of child deaths in children younger than 5 years. Yet, data regarding preterm birth (<37 completed weeks of gestation) are not routinely collected by UN agencies, and no systematic country estimates nor time trend analyses have been done. We report worldwide, regional, and national estimates of preterm birth rates for 184 countries in 2010 with time trends for selected countries, and provide a quantitative assessment of the uncertainty surrounding these estimates. METHODS: We assessed various data sources according to prespecified inclusion criteria. National Registries (563 datapoints, 51 countries), Reproductive Health Surveys (13 datapoints, eight countries), and studies identified through systematic searches and unpublished data (162 datapoints, 40 countries) were included. 55 countries submitted additional data during WHO's country consultation process. For 13 countries with adequate quality and quantity of data, we estimated preterm birth rates using country-level loess regression for 2010. For 171 countries, two regional multilevel statistical models were developed to estimate preterm birth rates for 2010. We estimated time trends from 1990 to 2010 for 65 countries with reliable time trend data and more than 10,000 livebirths per year. We calculated uncertainty ranges for all countries. FINDINGS: In 2010, an estimated 14·9 million babies (uncertainty range 12·3-18·1 million) were born preterm, 11·1% of all livebirths worldwide, ranging from about 5% in several European countries to 18% in some African countries. More than 60% of preterm babies were born in south Asia and sub-Saharan Africa, where 52% of the global livebirths occur. Preterm birth also affects rich countries, for example, USA has high rates and is one of the ten countries with the highest numbers of preterm births. Of the 65 countries with estimated time trends, only three (Croatia, Ecuador, and Estonia), had reduced preterm birth rates 1990-2010. INTERPRETATION: The burden of preterm birth is substantial and is increasing in those regions with reliable data. Improved recording of all pregnancy outcomes and standard application of preterm definitions is important. We recommend the addition of a data-quality indicator of the per cent of all live preterm births that are under 28 weeks' gestation. Distinguishing preterm births that are spontaneous from those that are provider-initiated is important to monitor trends associated with increased caesarean sections. Rapid scale up of basic interventions could accelerate progress towards Millennium Development Goal 4 for child survival and beyond. FUNDING: Bill & Melinda Gates Foundation through grants to Child Health Epidemiology Reference Group (CHERG) and Save the Children's Saving Newborn Lives programme; March of Dimes; the Partnership for Maternal Newborn and Childe Health; and WHO, Department of Reproductive Health and Research.


Assuntos
Saúde Global , Nascimento Prematuro/epidemiologia , Criança , Mortalidade da Criança/tendências , Coleta de Dados , Bases de Dados Factuais/estatística & dados numéricos , Países Desenvolvidos/estatística & dados numéricos , Países em Desenvolvimento/estatística & dados numéricos , Feminino , Humanos , Nascido Vivo/epidemiologia , Gravidez
9.
Pediatr Res ; 74 Suppl 1: 17-34, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24366461

RESUMO

BACKGROUND: In 2010, there were an estimated 15 million preterm births worldwide (<37 wk gestation). Survivors are at risk of adverse outcomes, and burden estimation at global and regional levels is critical for priority setting. METHODS: Systematic reviews and meta-analyses were undertaken to estimate the risk of long-term neurodevelopmental impairment for surviving preterm babies according to the level of care. A compartmental model was used to estimate the number of impaired postneonatal survivors following preterm birth in 2010. A separate model (DisMod-MR) was used to estimate years lived with disability (YLDs) for the global burden of disease 2010 study. Disability adjusted life years (DALYs) were calculated as the sum of YLDs and years of life lost (YLLs). RESULTS: In 2010, there were an estimated 13 million preterm births who survived beyond the first month. Of these, 345,000 (2.7%, uncertainty range: 269,000-420,000) were estimated to have moderate or severe neurodevelopmental impairment, and a further 567,000 (4.4%, (445,000-732,000)) were estimated to have mild neurodevelopmental impairment. Many more have specific learning or behavioral impairments or reduced physical or mental health. Fewest data are available where the burden is heaviest. Preterm birth was responsible for 77 million DALYs, 3.1% of the global total, of which only 3 million were YLDs. CONCLUSION: Most preterm births (>90%) survive without neurodevelopmental impairment. Developing effective means of prevention of preterm birth should be a longer term priority, but major burden reduction could be made immediately with improved coverage and quality of care. Improved newborn care would reduce mortality, especially in low-income countries and is likely to reduce impairment in survivors, particularly in middle-income settings.


Assuntos
Deficiências do Desenvolvimento/epidemiologia , Saúde Global/estatística & dados numéricos , Nascimento Prematuro/epidemiologia , Deficiências do Desenvolvimento/história , História do Século XXI , Humanos , Recém-Nascido , Modelos Estatísticos , Nascimento Prematuro/história , Medição de Risco
10.
Sci Rep ; 9(1): 11286, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375756

RESUMO

Over the past decade, several immunotherapies have been approved for the treatment of melanoma. The most prominent of these are the immune checkpoint inhibitors, which are antibodies that block the inhibitory effects on the immune system by checkpoint receptors, such as CTLA-4, PD-1 and PD-L1. Preclinically, blocking these receptors has led to increased activation and proliferation of effector cells following stimulation and antigen recognition, and subsequently, more effective elimination of cancer cells. Translation from preclinical to clinical outcomes in solid tumors has shown the existence of a wide diversity of individual patient responses, linked to several patient-specific parameters. We developed a quantitative systems pharmacology (QSP) model that looks at the mentioned checkpoint blockade therapies administered as mono-, combo- and sequential therapies, to show how different combinations of specific patient parameters defined within physiological ranges distinguish different types of virtual patient responders to these therapies for melanoma. Further validation by fitting and subsequent simulations of virtual clinical trials mimicking actual patient trials demonstrated that the model can capture a wide variety of tumor dynamics that are observed in the clinic and can predict median clinical responses. Our aim here is to present a QSP model for combination immunotherapy specific to melanoma.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Antígeno CTLA-4/antagonistas & inibidores , Melanoma/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/imunologia , Antígeno CTLA-4/imunologia , Humanos , Imunoterapia/efeitos adversos , Melanoma/imunologia , Melanoma/patologia , Modelos Teóricos , Pacientes , Receptor de Morte Celular Programada 1/imunologia
11.
Clin Transl Sci ; 12(5): 450-458, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30883000

RESUMO

Tremelimumab, an anti-cytotoxic T-lymphocyte antigen-4 monoclonal antibody that enhances T-cell activation, was evaluated in a randomized, double-blind, placebo-controlled, phase IIb study (NCT01843374) in patients with unresectable malignant mesothelioma. The study demonstrated no clinically meaningful differences in overall survival (OS). The objective of this analysis was to evaluate the relationship of exposure with OS. A population pharmacokinetic (PK) model adequately described the PK data. Three factors (sex, C-reactive protein, and baseline tumor size) were identified as statistically significant PK predictors (P < 0.05 on clearance). A positive association between exposure and OS was observed. However, an association between key baseline factors with OS (regardless of treatment) and imbalances in prognostic factors favoring patients with higher exposure (upper vs. lower PK quartile) was seen. Taken together, these results suggest that the exposure OS relationship observed for tremelimumab in mesothelioma is likely spurious rather than a true association of exposure with efficacy.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Anticorpos Monoclonais Humanizados/farmacocinética , Fatores de Confusão Epidemiológicos , Humanos , Estimativa de Kaplan-Meier , Mesotelioma Maligno , Modelos Biológicos , Fatores de Risco
12.
AAPS J ; 21(5): 79, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31236847

RESUMO

Immunotherapy and immune checkpoint blocking antibodies such as anti-PD-1 are approved and significantly improve the survival of advanced non-small cell lung cancer (NSCLC) patients, but there has been little success in identifying biomarkers capable of separating the responders from non-responders before the onset of the therapy. In this study, we developed a quantitative system pharmacology (QSP) model to represent the anti-tumor immune response in human NSCLC that integrated our knowledge of tumor growth, antigen processing and presentation, T cell activation and distribution, antibody pharmacokinetics, and immune checkpoint dynamics. The model was calibrated with the available data and was used to identify potential biomarkers as well as patient-specific response based on the patient parameters. The model predicted that in addition to tumor mutational burden (TMB), a known biomarker for anti-PD-1 therapy in NSCLC, the number of effector T cells and regulatory T cells in the tumor and blood is a predictor of the responders. Furthermore, the model simulated a set of 12 patients with known TMB and MHC/antigen-binding affinity from a recent clinical trial ( ClinicalTrials.gov number, NCT02259621) on neoadjuvant nivolumab therapy in resectable lung cancer and predicted an augmented durable response in patients with adjuvant nivolumab treatment in addition to the clinical trial protocol of neoadjuvant nivolumab treatment followed by resection. Overall, the model provides a valuable framework to model tumor immunity and response to immune checkpoint blockers to enhance biomarker discovery and performing virtual clinical trials to aid in design and interpretation of the current trials with fewer patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Modelos Biológicos , Nivolumabe/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/farmacologia , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Ensaios Clínicos como Assunto , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Terapia Neoadjuvante , Nivolumabe/farmacologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores
13.
Sci Rep ; 9(1): 2402, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30787348

RESUMO

The role of phospholipid modification initiated by phospholipase D (PLD) in enzymatic browning has been revoked through this study. Various alcohols and aldehydes were tried to read out their PLD controlling behaviour. Based on in-vitro results, reagents like hexanal and inositol were used to regulate PLD activity of litchi fruit stored at ambient temperature and their effects on fruit quality and physiological characteristics were also investigated. The results showed that combinatorial chemical treatment was successful in maintaining freshness of fruit through delayed physiological loss in weight and hence maintaining firmness. Combinatorial treated fruit had lower browning index than control by day 7. This novel treatment also maintained comparable levels of total phenolics and lowered the level of malondialdehyde. Evaluation of antioxidative enzymatic profile also confirmed the alleviation of oxidative stress of litchi fruit at ambient temperature. Thus, this strategy of enzyme regulation could play a vital role in overall quality maintenance of litchi fruit.


Assuntos
Aldeídos/farmacologia , Inositol/farmacologia , Litchi/efeitos dos fármacos , Fosfolipase D/genética , Antioxidantes/farmacologia , Frutas/química , Frutas/efeitos dos fármacos , Litchi/metabolismo , Reação de Maillard/efeitos dos fármacos , Ácidos Fosfatídicos/metabolismo , Fosfolipídeos/metabolismo
14.
R Soc Open Sci ; 6(5): 190366, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31218069

RESUMO

The low response rate of immune checkpoint blockade in breast cancer has highlighted the need for predictive biomarkers to identify responders. While a number of clinical trials are ongoing, testing all possible combinations is not feasible. In this study, a quantitative systems pharmacology model is built to integrate immune-cancer cell interactions in patients with breast cancer, including central, peripheral, tumour-draining lymph node (TDLN) and tumour compartments. The model can describe the immune suppression and evasion in both TDLN and the tumour microenvironment due to checkpoint expression, and mimic the tumour response to checkpoint blockade therapy. We investigate the relationship between the tumour response to checkpoint blockade therapy and composite tumour burden, PD-L1 expression and antigen intensity, including their individual and combined effects on the immune system, using model-based simulations. The proposed model demonstrates the potential to make predictions of tumour response of individual patients given sufficient clinical measurements, and provides a platform that can be further adapted to other types of immunotherapy and their combination with molecular-targeted therapies. The patient predictions demonstrate how this systems pharmacology model can be used to individualize immunotherapy treatments. When appropriately validated, these approaches may contribute to optimization of breast cancer treatment.

15.
Clin Lung Cancer ; 20(6): e601-e608, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31327642

RESUMO

INTRODUCTION: Two clinical studies (Study 1108 and ATLANTIC) were analyzed to evaluate the prognostic value of baseline liver metastases (LMs) in advanced/metastatic non-small-cell lung cancer patients treated with durvalumab 10 mg/kg every 2 weeks. PATIENTS AND METHODS: A multivariate Cox proportional hazards analysis was conducted; covariates included performance status, tumor stage, histology, sex, age, smoking status, and programmed cell death ligand 1 (PD-L1) status. RESULTS: In all, 569 patients were included. LMs were present in 31.6% (96/304) of Study 1108 patients and 17.9% (47/263) of ATLANTIC patients. Median overall survival (OS) was shorter in patients with LMs than in those without in both studies. In both studies, LMs were an independent negative prognostic factor for OS and progression-free survival. Objective response rates were also significantly lower. PD-L1 independently predicted benefit across all patients. CONCLUSION: Liver metastases were associated with worse outcomes irrespective of PD-L1 status, but PD-L1 status predicted benefit from durvalumab irrespective of LMs.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Imunoterapia/métodos , Neoplasias Hepáticas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Idoso , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/secundário , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Metástase Neoplásica , Estadiamento de Neoplasias , Seleção de Pacientes , Prognóstico , Análise de Sobrevida , Resultado do Tratamento
16.
J Thorac Oncol ; 14(10): 1794-1806, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31228626

RESUMO

INTRODUCTION: Durvalumab is a selective, high-affinity human immunoglobulin G1 monoclonal antibody that blocks programmed cell death ligand 1 (PD-L1) binding to programmed death 1. Here we report safety and clinical activity in the NSCLC cohort of a phase I/II trial that included multiple tumor types (Study 1108; NCT01693562). METHODS: Patients with stage IIIB-IV NSCLC (squamous or nonsquamous) received durvalumab 10 mg/kg every 2 weeks for 12 months or until confirmed progressive disease or unacceptable toxicity. Primary objectives were safety and antitumor activity. Tumoral PD-L1 expression was assessed using the VENTANA SP263 Assay. Responses were assessed by blinded independent central review (Response Evaluation Criteria in Solid Tumors v1.1). Adverse events were graded according to National Cancer Institute's Common Terminology Criteria for Adverse Events (v4.03). RESULTS: Of 304 patients, 79.0% were previously treated. Confirmed objective response rate was 21.8% in patients with greater than or equal to 25% PD-L1 expression and 6.4% in those with less than 25%; 25.9% in first-line patients and 12.7% in previously treated patients; and 14.0% in squamous and 16.7% in nonsquamous disease. Median overall survival was 12.4 months and median progression-free survival was 1.7 months; both were numerically longer in the PD-L1 greater than or equal to 25% group than in the PD-L1 less than 25% group (overall survival 16.4 versus 7.6 months, respectively; progression-free survival 2.6 versus 1.4 months, respectively). Treatment-related adverse events occurred in 57.2%, were grade 3/4 in 10.2%, and led to discontinuation in 5.6%. One patient (0.3%) died of treatment-related pneumonia with underlying pneumonitis. CONCLUSIONS: Durvalumab was clinically active irrespective of histology in this mostly pretreated population, with a manageable safety profile. Response rates and survival appeared to be enhanced in patients with greater tumoral PD-L1 expression.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/farmacocinética , Antineoplásicos Imunológicos/farmacocinética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Prognóstico , Critérios de Avaliação de Resposta em Tumores Sólidos , Taxa de Sobrevida , Distribuição Tecidual
17.
Indian J Community Med ; 43(4): 255-259, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30662175

RESUMO

Universal Health Coverage (UHC) is now the critical yardstick for countries to measure and track progress toward the "Sustainable Development Goals (SDGs)." Being a signatory, India has started taking measures to attain the targets laid out within the SDG framework and achieving the UHC. With India's National Health Policy (NHP) - 2017 in place, the policy environment for transforming country's health landscape coincides with that of the global approach toward strengthening of health systems and achieving UHC. It is imperative that for achieving the desired outcomes laid down in the SDGs and NHP-2017, coordinated actions are required including political action for making health an individual's right; effective stewardship from the National Ministry of Health and Family Welfare; reorganization of health-care service delivery implementing a "systems approach;" ensuring financial protection against health-care costs; and enhancing community participation and accountability. Undertaking these steps, imbibing the learning, and dwelling upon global experiences can help the country strongly move forward towards achieving global and national targets, thereby ensuring UHC for all its citizens.

18.
Clin Pharmacol Ther ; 103(4): 643-652, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29243222

RESUMO

Durvalumab is an anti-PD-L1 monoclonal antibody approved for patients with locally advanced or metastatic urothelial carcinoma (UC) that has progressed after platinum-containing chemotherapy. A population tumor kinetic model, coupled with dropout and survival models, was developed to describe longitudinal tumor size data and predict overall survival in UC patients treated with durvalumab (NCT01693562) and to identify prognostic and predictive biomarkers of clinical outcomes. Model-based covariate analysis identified liver metastasis as the most influential factor for tumor growth and immune-cell PD-L1 expression and baseline tumor burden as predictive factors for tumor killing. Tumor or immune-cell PD-L1 expression, liver metastasis, baseline hemoglobin, and albumin levels were identified as significant covariates for overall survival. These model simulations provided further insights into the impact of PD-L1 cutoff values on treatment outcomes. The modeling framework can be a useful tool to guide patient selection and enrichment strategies for immunotherapies across various cancer indications.


Assuntos
Anticorpos Monoclonais , Antígeno B7-H1/imunologia , Carcinoma , Neoplasias Hepáticas , Neoplasias Urológicas , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/farmacocinética , Biomarcadores Tumorais/imunologia , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Masculino , Modelos Biológicos , Invasividade Neoplásica , Estadiamento de Neoplasias , Avaliação de Resultados em Cuidados de Saúde , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida , Carga Tumoral , Neoplasias Urológicas/tratamento farmacológico , Neoplasias Urológicas/patologia , Urotélio/patologia
19.
Clin Pharmacol Ther ; 103(4): 631-642, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29243223

RESUMO

The objectives of this analysis were to develop a population pharmacokinetics (PK) model of durvalumab, an anti-PD-L1 antibody, and quantify the impact of baseline and time-varying patient/disease characteristics on PK. Pooled data from two studies (1,409 patients providing 7,407 PK samples) were analyzed with nonlinear mixed effects modeling. Durvalumab PK was best described by a two-compartment model with both linear and nonlinear clearances. Three candidate models were evaluated: a time-invariant clearance (CL) model, an empirical time-varying CL model, and a semimechanistic time-varying CL model incorporating longitudinal covariates related to disease status (tumor shrinkage and albumin). The data supported a slight decrease in durvalumab clearance with time and suggested that it may be associated with a decrease in nonspecific protein catabolic rate among cancer patients who benefit from therapy. No covariates were clinically relevant, indicating no need for dose adjustment. Simulations indicated similar overall PK exposures following weight-based and flat-dosing regimens.


Assuntos
Anticorpos Monoclonais/farmacocinética , Cálculos da Dosagem de Medicamento , Taxa de Depuração Metabólica , Neoplasias/tratamento farmacológico , Antineoplásicos Imunológicos/farmacocinética , Antígeno B7-H1/imunologia , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Estadiamento de Neoplasias , Neoplasias/classificação , Neoplasias/imunologia , Neoplasias/patologia
20.
J R Soc Interface ; 14(134)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28931635

RESUMO

When the immune system responds to tumour development, patterns of immune infiltrates emerge, highlighted by the expression of immune checkpoint-related molecules such as PDL1 on the surface of cancer cells. Such spatial heterogeneity carries information on intrinsic characteristics of the tumour lesion for individual patients, and thus is a potential source for biomarkers for anti-tumour therapeutics. We developed a systems biology multiscale agent-based model to capture the interactions between immune cells and cancer cells, and analysed the emergent global behaviour during tumour development and immunotherapy. Using this model, we are able to reproduce temporal dynamics of cytotoxic T cells and cancer cells during tumour progression, as well as three-dimensional spatial distributions of these cells. By varying the characteristics of the neoantigen profile of individual patients, such as mutational burden and antigen strength, a spectrum of pretreatment spatial patterns of PDL1 expression is generated in our simulations, resembling immuno-architectures obtained via immunohistochemistry from patient biopsies. By correlating these spatial characteristics with in silico treatment results using immune checkpoint inhibitors, the model provides a framework for use to predict treatment/biomarker combinations in different cancer types based on cancer-specific experimental data.


Assuntos
Antígeno B7-H1/imunologia , Modelos Imunológicos , Proteínas de Neoplasias/imunologia , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T/imunologia , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA