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1.
Urol Oncol ; 39(12): 834.e1-834.e7, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34162500

RESUMO

PURPOSE: To compare healthcare resource utilization (HRU) and costs associated with dose-dense methotrexate, vinblastine, doxorubicin, cisplatin (ddMVAC) and gemcitabine, cisplatin (GC) as neoadjuvant chemotherapy for muscle-invasive bladder cancer (MIBC). METHODS: Patient treated at Dana-Farber Cancer Institute from 2010 to 2019 were identified. HRU data on chemotherapy administered, supportive medications, patient monitoring, clinic, infusion, emergency department (ED) visits and hospitalization were collected retrospectively. Unit costs for HRU components were obtained from the Centers for Medicare and Medicaid Website and HRU was compared between groups using quantile regression analysis. RESULTS: 137 patients were included; 51 received ddMVAC and 86 GC. Baseline characteristics were similar, except lower mean age (P < 0.001) and higher proportion of ECOG-PS = 0 (P < 0.001) for ddMVAC. ddMVAC required more granulocyte-colony stimulating factor support (P < 0.001), central line placement (P = 0.017), cardiac imaging (P < 0.001), and infusion visits (P < 0.001), whereas GC required more clinic visits. ED visits were higher for ddMVAC (P = 0.048), while chemotherapy cycle delays and hospitalization days were higher for GC (P = 0.008). After adjusting for ECOG-PS and age, the cost per patient was approximately 41% lower (95%CI: 28% to 52%; P < 0.001) for GC vs. ddMVAC, which translated to a median adjusted cost savings of $7,410 (95%CI: $5,474-$9,347) per patient. CONCLUSIONS: Although excess HRU did not clearly favor one regimen, adjusting for PS and age indicated lower costs with GC vs. ddMVAC. Given the similar cumulative cisplatin delivery with both regimens, the associated values and costs supports the preferential selection of GC in the neoadjuvant setting of MIBC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Atenção à Saúde/economia , Desoxicitidina/análogos & derivados , Doxorrubicina/uso terapêutico , Metotrexato/uso terapêutico , Terapia Neoadjuvante/métodos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/economia , Vimblastina/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cisplatino/farmacologia , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Doxorrubicina/farmacologia , Feminino , Humanos , Masculino , Metotrexato/farmacologia , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Vimblastina/farmacologia , Gencitabina
2.
Exp Cell Res ; 405(2): 112660, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34048785

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers with an extremely poor prognosis. Gemcitabine (Gem) is still the mainstay drug for the treatment of PDAC. However, rapid inactivation by cytidine deaminase (CDA) present in pancreatic cancer cells severely limits anticancer efficacy of Gem. In this study, we investigated the effect of a CDA inhibitor - Zebularine (Zeb) on anticancer activity of Gem in pancreatic cancer cell lines MiaPaCa-2, BxPC-3, and Panc-1. Zeb treatment synergistically increased Gem-induced cytotoxicity in all three pancreatic cancer cell lines. The strongest synergistic activity was found at 1:10 M ratio of Gem/Zeb (combination index 0.04-0.4). Additionally, Gem + Zeb treated cells showed marked decreased in the expressions of anti-apoptotic protein including Bcl-2 and survivin while significantly increased the cleaved caspase-3, and loss of mitochondrial membrane potential was observed. Multicellular 3D spheroids of MiaPaCa-2 cells treated with combination showed significant reduction (25-60%) in spheroid size, weight compared to single drug and control group. Live/dead cell imaging showed that Gem + Zeb treated spheroids exhibited a highly distorted surface with significantly higher number of dead cells (red). The results of the present study confirm that this synergistic combination is worthy of future investigations as a potential approach for the treatment of PDAC.


Assuntos
Citidina/análogos & derivados , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Antimetabólitos Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Citidina/farmacologia , Citidina Desaminase/efeitos dos fármacos , Citidina Desaminase/metabolismo , Desoxicitidina/farmacologia , Humanos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Neoplasias Pancreáticas/patologia , Gencitabina , Neoplasias Pancreáticas
3.
Bull Exp Biol Med ; 170(1): 142-147, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33231795

RESUMO

The study was designed to create a primary cell culture of uveal melanoma and to evaluate its resistance to chemotherapy. Of the obtained 20 samples of uveal melanoma, the primary cultures with proliferation sufficient for MTT test were derived in only 7 cases. However, even these cultures were unable to survive more than 4 passages; the cells accumulated melanin and underwent apoptosis. Retinol palmitate and nepafenac produced no cytotoxic effect on uveal melanoma cells. Of 5 cultures treated with sodium valproate (Convulex), no pronounced cytotoxic effect was observed in one culture (UM4); in 2 cultures, 50% cells died in the presence of the lowest drug concentration of 1.88 mg/ml; and in 2 cultures, the same effect was achieved at drug concentrations 7-10 mg/ml. The cytotoxic effect of treosulfan was evaluated in only 4 cultures of uveal melanoma: the drug exhibited pronounced antitumor activity on all cultures, in 2 cases, it was effective at a concentration of 0.16 mg/ml. Gemcitabine in a concentration of 2.5 mg/ml produced a pronounced cytotoxic effect in 4 out of 7 cultures (death of 70-80% cells) and induced death of ~45% cells in the remaining 3 cultures. Mitoxantrone had ambiguous effect: in 2 of 5 cultures, the drug in high concentrations stimulated the growth of tumor cells, but in 3 cultures, the drug even in minimum concentrations induced death of 70-80% cells.


Assuntos
Antineoplásicos/farmacologia , Benzenoacetamidas/farmacologia , Bussulfano/análogos & derivados , Desoxicitidina/análogos & derivados , Diterpenos/farmacologia , Fenilacetatos/farmacologia , Ésteres de Retinil/farmacologia , Ácido Valproico/farmacologia , Adulto , Idoso , Bussulfano/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias da Coroide/tratamento farmacológico , Neoplasias da Coroide/patologia , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Masculino , Melanoma/tratamento farmacológico , Melanoma/patologia , Pessoa de Meia-Idade , Cultura Primária de Células , Células Tumorais Cultivadas , Neoplasias Uveais/tratamento farmacológico , Neoplasias Uveais/patologia , Gencitabina
4.
Int J Med Sci ; 17(6): 824-833, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32218704

RESUMO

Due to the high toxicity of currently used chemotherapeutics, novel methods of cancer treatment are needed. Gold nanoparticles (AuNPs) seem to be an interesting alternative due to penetration through biological membranes and systemic barriers. AuNPs as carriers of chemotherapeutics allow for reduced concentrations whilst maintaining the expected effect, and thus reducing the costs of therapy and adverse effects. We synthesized AuNPs stabilized with reduced glutathione (GSH) and conjugated with doxorubicin (DOX), gemcitabine (GEM) or cytarabine (CTA). This is the first study in which cytarabine-AuNPs were synthesized and characterized. Transmission electron microscopy (TEM), thermogravimetric analysis (TGA), nuclear magnetic resonance spectroscopy (NMR) and high-performance liquid chromatography (HPLC) were used to chemically characterize obtained nanoparticles. Antitumor activity and safety of application were assessed by MTT assay in in vitro model (human osteosarcoma cells -143B, human osteoblast- hFOB1.19, breast cancer cells - MCF7, breast epithelial cells - MCF10A, pancreatic cancer cells - PANC-1, and pancreatic cells - hTERT-HPNE cells). We have shown that cellular response varies according to the type and concentration of AuNPs. At some concentrations, we were able to show selective cytotoxicity of our AuNPs conjugates only to cancer cell lines. Synthesized nanoparticles were more cytotoxic to tumor cell lines than chemotherapeutics alone.


Assuntos
Glutationa/farmacologia , Ouro/química , Nanopartículas Metálicas/química , Neoplasias/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Citarabina/química , Citarabina/farmacologia , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Desoxicitidina/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Glutationa/química , Ouro/efeitos adversos , Humanos , Células MCF-7 , Nanopartículas Metálicas/efeitos adversos , Microscopia Eletrônica de Transmissão , Neoplasias/genética , Neoplasias/patologia , Osteoblastos/efeitos dos fármacos , Telomerase/química , Gencitabina
5.
Biomech Model Mechanobiol ; 19(2): 427-444, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31501963

RESUMO

More than eighty percent of pancreatic cancer involves ductal adenocarcinoma with an abundant desmoplastic extracellular matrix surrounding the solid tumor entity. This aberrant tumor microenvironment facilitates a strong resistance of pancreatic cancer to medication. Although various therapeutic strategies have been reported to be effective in mice with pancreatic cancer, they still need to be tested quantitatively in wider animal-based experiments before being applied as therapies. To aid the design of experiments, we develop a cell-based mathematical model to describe cancer progression under therapy with a specific application to pancreatic cancer. The displacement of cells is simulated by solving a large system of stochastic differential equations with the Euler-Maruyama method. We consider treatment with the PEGylated drug PEGPH20 that breaks down hyaluronan in desmoplastic stroma followed by administration of the chemotherapy drug gemcitabine to inhibit the proliferation of cancer cells. Modeling the effects of PEGPH20 + gemcitabine concentrations is based on Green's fundamental solutions of the reaction-diffusion equation. Moreover, Monte Carlo simulations are performed to quantitatively investigate uncertainties in the input parameters as well as predictions for the likelihood of success of cancer therapy. Our simplified model is able to simulate cancer progression and evaluate treatments to inhibit the progression of cancer.


Assuntos
Simulação por Computador , Neoplasias Pancreáticas/patologia , Anisotropia , Morte Celular , Divisão Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Matriz Extracelular/metabolismo , Humanos , Hialuronoglucosaminidase/administração & dosagem , Hialuronoglucosaminidase/farmacologia , Hialuronoglucosaminidase/uso terapêutico , Injeções , Método de Monte Carlo , Estadiamento de Neoplasias , Análise Numérica Assistida por Computador , Neoplasias Pancreáticas/tratamento farmacológico , Processos Estocásticos , Gencitabina
6.
Anticancer Res ; 39(12): 6673-6684, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810932

RESUMO

BACKGROUND/AIM: The aim of the study was to evaluate the antitumor potential and combination effects of chemotherapeutic drugs. MATERIALS AND METHODS: The cytotoxicity of 20 drip-type classical and molecular-targeted anticancer drugs was examined against 4 human oral squamous cell carcinoma cell lines and 5 human oral normal mesenchymal and epithelial cells. Cell cycle progression was monitored by a cell sorter. Combination effect was evaluated by combination index. RESULTS: Most of the classical anticancer drugs showed much higher antitumor activity than molecular-targeted drugs, except bortezomib. Among 12 classical anticancer drugs, taxanes and gemsitabine showed the highest tumor-specificity (TS) and potency-selectivity expression (PSE) values, whereas platinum analogs showed the least TS value. Combination of two classical or a classical and a molecular-targeted drug showed mostly additive or antagonistic effect. 5-FU and cisplatin did not produce a subG1 population, but induced G2/M or G1/S arrest, regardless of the addition of cetuximab. Cetuximab, nibolumab and bortezomib showed potent keratinocyte toxicity. CONCLUSION: The present TS monitoring system may provide useful information for building up the treatment regimens of anticancer drugs.


Assuntos
Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Células Epiteliais/efeitos dos fármacos , Terapia de Alvo Molecular , Neoplasias Bucais/tratamento farmacológico , Bortezomib/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cetuximab/farmacologia , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/efeitos dos fármacos , Fluoruracila/farmacologia , Hormese , Humanos , Técnicas In Vitro , Queratinócitos/efeitos dos fármacos , Mucosa Bucal/citologia , Nivolumabe/farmacologia , Compostos de Platina/farmacologia , Taxoides/farmacologia , Gencitabina
7.
Oncology (Williston Park) ; 32(9): 437-42, 444, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30248163

RESUMO

Oxaliplatin-based chemotherapy (FOLFOX [folinic acid, fluorouracil, oxaliplatin] or XELOX [oxaliplatin, capecitabine; also called CAPOX]) for 6 months is the current standard for adjuvant therapy of stage III colon cancer patients with good performance status. However, these regimens are associated with significant toxicities, including myelosuppression, diarrhea, and oxaliplatin-induced, cumulative, dose-dependent neurotoxicity. A reduced duration of adjuvant therapy, which would reduce overall toxicity while maintaining overall clinical efficacy, would be optimal. The goal of the International Duration Evaluation of Adjuvant (IDEA) study was to evaluate the noninferiority of 3-month compared with 6-month adjuvant oxaliplatin-based treatment in stage III colon cancer using a prospectively designed pooled analysis of 6 concurrently conducted phase III randomized trials. Herein, we review the findings of the IDEA study and discuss the optimal duration of oxaliplatin-based adjuvant chemotherapy using patient-based risk factors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias do Colo , Desoxicitidina/análogos & derivados , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Fluoruracila/análogos & derivados , Conduta do Tratamento Medicamentoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina , Quimioterapia Adjuvante , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Humanos , Leucovorina/farmacologia , Estadiamento de Neoplasias , Compostos Organoplatínicos/farmacologia , Oxaloacetatos , Fatores de Tempo , Resultado do Tratamento
8.
Ann Oncol ; 29(8): 1741-1747, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29905759

RESUMO

Background: CBCSG006 trial reported the superior efficacy of cisplatin plus gemcitabine (GP) regimen than paclitaxel plus gemcitabine (GT) regimen as first-line treatment of metastatic triple-negative breast cancer (mTNBC). This study focused on the updated survival data and the explorations of potential biomarkers for efficacy. Patients and methods: Germ-line mutations of homologous recombination (HR) panel, BRCA1/2 included, were evaluated in 55.9% (132/236) patients. PD-L1 expression was evaluated in 48.3% (114/236) patients. A nonparametric sliding-window subpopulation treatment effect pattern plot (STEPP) methodology was used to analyze the absolute survival benefits. All statistical tests were two-sided. Results: Median progression-free survival (PFS) was 7.73 [95% confidence interval (CI) 6.46-9.00] months for GP arm and 6.07 (95% CI 5.32-6.83) months for GT arm (P = 0.005). No significant difference in overall survival (OS) was observed. There was significant interaction between HR status and treatment for PFS and status of HR deficient significantly correlated with higher objective response rate (ORR) and longer PFS in GP arm than in GT arm (71.9% versus 38.7%, P = 0.008; 10.37 versus 4.30 months, P = 0.011). There was no significant interaction between germ-line BRCA1/2 (gBRCA1/2) status and treatment for PFS. Patients with gBRCA1/2 mutation had numerically higher ORR and prolonged PFS in GP arm than in GT arm (83.3% versus 37.5%, P = 0.086; 8.90 versus 3.20 months, P = 0.459). There was no significant interaction between PD-L1 status and treatment for PFS, and no significant differences in ORR, PFS or OS between two arms regardless of PD-L1 status. In STEPP analysis, patients with lower composite risks had more absolute benefits in PFS than those with higher composite risks. Conclusions: GP regimen has superior efficacy than GT regimen as first-line chemotherapy for mTNBC patients. Germ-line mutations of BRCA1/2 and HR panel are possible biomarkers for better performance of cisplatin-based regimens. A composite risk model was developed to guide patient selection for GP treatment in TNBC patients. Trial registration: ClinicalTrials.gov, NCT01287624.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Seleção de Pacientes , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Biomarcadores Tumorais/metabolismo , Mama/patologia , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Seguimentos , Mutação em Linhagem Germinativa , Humanos , Estimativa de Kaplan-Meier , Modelos Biológicos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Intervalo Livre de Progressão , Estudos Prospectivos , Medição de Risco/métodos , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Gencitabina
9.
AAPS J ; 20(5): 80, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29951754

RESUMO

The pharmacodynamic interactions among trifluoperazine (TFP), gemcitabine (GEM), and paclitaxel (PTX) were assessed in pancreatic cancer cells (PANC-1). The phenothiazine TFP was chosen for its potential activity on cancer stem cells, while GEM and PTX cause apoptosis. Effects of each drug alone and in various combinations on cell growth inhibition of PANC-1 cells were studied in vitro to determine the drug-specific parameters and assess the nature of drug interactions. Joint inhibition (JI) and competitive inhibition (CI) equations were applied with a ψ interaction term. TFP fully inhibited growth of cells (Imax = 1) with an IC50 = 9887 nM. Near-maximum inhibition was achieved for GEM (Imax = 0.825) and PTX (Imax= 0.844) with an IC50 = 17.4 nM for GEM and IC50 = 7.08 nM for PTX. Estimates of an interaction term ψ revealed that the combination of TFP-GEM was apparently synergistic; close to additivity, the combination TFP-PTX was antagonistic. The interaction of GEM-PTX was additive, and TFP-GEM-PTX was synergistic but close to additive. The combination of TFP IC60-GEM IC60-PTX IC60 seemed optimal in producing inhibition of PANC-1 cells with an inhibitory effect of 82.1-90.2%. The addition of ψ terms to traditional interaction equations allows assessment of the degree of perturbation of assumed mechanisms.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Células-Tronco Neoplásicas/efeitos dos fármacos , Paclitaxel/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Trifluoperazina/farmacologia , Linhagem Celular Tumoral , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Humanos , Concentração Inibidora 50 , Modelos Biológicos , Células-Tronco Neoplásicas/patologia , Neoplasias Pancreáticas/patologia , Gencitabina
10.
Biol Pharm Bull ; 41(2): 220-228, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29386482

RESUMO

Previously, we developed a method to evaluate states of cells treated with anticancer drugs via the comprehensive analysis of amino acids, termed amino acid metabolomics. In the present study, we evaluated the effects of the anticancer drugs, gemcitabine hydrochloride and pyrvinium pamoate, on the proliferation of a pancreatic cancer cell line (PANC-1) under hypoglycemic conditions using amino acid metabolomics. Intracellular and extracellular amino acid profiles of PANC-1 were determined by hydrophilic interaction chromatography-tandem mass spectrometry with simple pretreatment. Changes to the drugs' anticancer effects resulting from glucose starvation conditions were presented in score plots obtained from principal component analyses. In particular, the analysis of intracellular amino acids was found to be the superior approach because the results allowed a clearer assessment of the cell state. Further, orthogonal partial least squares discriminant analysis was performed to search for amino acid candidates that discriminate with anticancer drug-treated PANC-1 cells. We identified several amino acids that might be able to distinguish the drug-treated group from the control group. These results might provide a better understanding of the mechanisms underlying cell responses such as drug resistance or austerity. The present study is the first to evaluate the efficacy of anticancer drugs under glucose starvation based on the analysis of the variation of extracellular and intracellular amino acid profiles in vitro.


Assuntos
Aminoácidos/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Líquido Extracelular/metabolismo , Líquido Intracelular/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Compostos de Pirvínio/farmacologia , Aminoácidos/química , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Glicemia/análise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Desoxicitidina/farmacologia , Análise Discriminante , Glucose/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Hipoglicemia/sangue , Hipoglicemia/complicações , Hipoglicemia/metabolismo , Análise dos Mínimos Quadrados , Metabolômica/métodos , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/metabolismo , Análise de Componente Principal , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Gencitabina
11.
Pancreatology ; 17(5): 795-804, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28619283

RESUMO

BACKGROUND/OBJECTIVES: There has been minimal improvement in the prognosis of pancreatic cancer cases in the past 3 decades highlighting the crucial need for more effective therapeutic approaches. A drug delivery system capable of locally delivering high concentrations of chemotherapeutics directly at the site of the tumor is clearly required. The aim of this study was to fabricate and characterize the biophysical properties of gemcitabine-eluting wet-spun polymeric fibers for localized drug delivery applications. METHODS/RESULTS: Fibers spun from alginate or chitosan solutions with or without the anticancer drug gemcitabine had a uniform surface area, were internally homogeneous and ranged from 50-120 µm in diameter. Drug encapsulation ranged from 13-52%, depending on the type and concentration of polymer used. Gemcitabine displayed first-order release kinetics where 64-82% of the loaded drug was rapidly released within the first 10 h followed by a sustained release over the next 134 h. A time dependent inhibition of ex vivo tumor spheroid growth and cell viability was observed after incubation with gemcitabine-loaded fibers but not control fibers. CONCLUSION: With further development these studies could lead to the manufacture of a safe and effective delivery system designed to combat non-resectable pancreatic cancer for which currently there is minimal chance of cure.


Assuntos
Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Adenocarcinoma/tratamento farmacológico , Alginatos , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/química , Desoxicitidina/farmacologia , Sistemas de Liberação de Medicamentos , Feminino , Ácido Glucurônico , Ácidos Hexurônicos , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Polímeros/química , Gencitabina
12.
Cancer Res ; 76(24): 7096-7105, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27784748

RESUMO

3'-Deoxy-3'-[18F]fluorothymidine positron emission tomography ([18F]FLT-PET) and diffusion-weighted MRI (DW-MRI) are promising approaches to monitor tumor therapy response. Here, we employed these two imaging modalities to evaluate the response of lung carcinoma xenografts in mice after gemcitabine therapy. Caliper measurements revealed that H1975 xenografts responded to gemcitabine treatment, whereas A549 growth was not affected. In both tumor models, uptake of [18F]FLT was significantly reduced 6 hours after drug administration. On the basis of the gemcitabine concentration and [18F]FLT excretion measured, this was presumably related to a direct competition of gemcitabine with the radiotracer for cellular uptake. On day 1 after therapy, [18F]FLT uptake was increased in both models, which was correlated with thymidine kinase 1 (TK1) expression. Two and 3 days after drug administration, [18F]FLT uptake as well as TK1 and Ki67 expression were unchanged. A reduction in [18F]FLT in the responsive H1975 xenografts could only be noted on day 5 of therapy. Changes in ADCmean in A549 xenografts 1 or 2 days after gemcitabine did not seem to be of therapy-related biological relevance as they were not related to cell death (assessed by caspase-3 IHC and cellular density) or tumor therapy response. Taken together, in these models, early changes of [18F]FLT uptake in tumors reflected mechanisms, such as competing gemcitabine uptake or gemcitabine-induced thymidylate synthase inhibition, and only reflected growth-inhibitory effects at a later time point. Hence, the time point for [18F]FLT-PET imaging of tumor response to gemcitabine is of crucial importance. Cancer Res; 76(24); 7096-105. ©2016 AACR.


Assuntos
Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Animais , Western Blotting , Linhagem Celular Tumoral , Desoxicitidina/farmacologia , Didesoxinucleosídeos , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Camundongos , Camundongos Nus , Compostos Radiofarmacêuticos , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
13.
Artigo em Inglês | MEDLINE | ID: mdl-24940698

RESUMO

Cytidine deaminase (CDA) plays a crucial role in the degradation of cytidine analogs, such as gemcitabine and cytarabine. Several studies showed that a low CDA activity is associated with more toxicity but a higher efficacy, while a high activity will lead to a lower efficacy but less toxicity. A stratified dosing strategy based on the relative CDA activity would increase efficiency. In order to predict these events, a reliable measurement of CDA with a validated method is crucial. We aimed to determine which phenotype assay would be most suitable; a spectrophotometric assay using cytidine as a substrate, or an HPLC assay using gemcitabine as a substrate. In serum and whole blood of 26 volunteers, both assays showed an excellent correlation (R>0.999), but not in plasma nor in red blood cells. Moreover, there was no difference between males and females. In conclusion, the spectrophotometric assay seems the most simple and cost-effective test. It should be performed in serum, while it should be normalized on protein content as measured by the Bicinchoninic Acid.


Assuntos
Citarabina/farmacologia , Citidina Desaminase/sangue , Citidina Desaminase/metabolismo , Desoxicitidina/análogos & derivados , Ensaios Enzimáticos/métodos , Adulto , Análise Custo-Benefício , Desoxicitidina/farmacologia , Ensaios Enzimáticos/economia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem , Gencitabina
14.
Integr Biol (Camb) ; 5(3): 458-73, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23340828

RESUMO

We present an integrative general network inference methodology to infer genetic and metabolic pathways associated with oncological drug chemoresistance. This methodology is general because it can infer different kinds of networks from different kinds of data. It is integrative because it integrates model simulation in its framework and it assembles into a larger integrated network all the inferred networks. The inference model is a variational approximation of Bayesian inference for stochastic processes. We used the Bayesian framework due to its ability to incorporate prior knowledge and constraints in the inference procedure and to treat both partial data and a large amount of data whose dynamics laws are mostly unknown. We show the performance of this approach using a case study of the gemcitabine chemoresistance in pancreatic cancer cells. Our method, inferred from time series data of gene expressions and metabolites, concentrates first the network of interactions of genes responsible for the sensitivity and resistance to gemcitabine, then the metabolic network, and finally it merges the two networks into a larger network predicting the correlations between genes and metabolizing enzymes.


Assuntos
Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pancreáticas/tratamento farmacológico , Algoritmos , Antineoplásicos/farmacologia , Teorema de Bayes , Biotransformação , Linhagem Celular Tumoral , Biologia Computacional/métodos , Simulação por Computador , Desoxicitidina/farmacocinética , Desoxicitidina/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Cadeias de Markov , Redes e Vias Metabólicas , Modelos Estatísticos , Processos Estocásticos , Fatores de Tempo , Gencitabina
15.
Genet Epidemiol ; 36(4): 352-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22460780

RESUMO

With new technologies, multiple types of genomic data are commonly collected on a single set of samples. However, standard analysis methods concentrate on a single data type at a time and ignore the relationships between genes, proteins, and biochemical reactions that give rise to complex phenotypes. In this paper, we propose a novel integrative model to incorporate multiple types of genomic data into an association analysis with a complex phenotype. The method combines path analysis and stochastic search variable selection into a Bayesian hierarchical model that simultaneously identifies both direct and indirect genomic effects on the phenotype. Results from a simulation study and application of the Bayesian model to a pharmacogenomic study of the drug gemcitabine demonstrate greater sensitivity to detect genomic effects in some simulation scenarios, when compared to the standard single data type analysis. Further research is required to extend and modify this integrative modeling framework to increase computational efficiency to best capitalize on the wealth of information available across multiple genomic data types.


Assuntos
Teorema de Bayes , Polimorfismo de Nucleotídeo Único , Algoritmos , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Genômica , Humanos , Cadeias de Markov , Modelos Estatísticos , Modelos Teóricos , Método de Monte Carlo , Farmacogenética , Fenótipo , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Processos Estocásticos , Gencitabina
17.
Clin Cancer Res ; 17(11): 3706-15, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21482692

RESUMO

PURPOSE: Chk1 inhibitors, such as AZD7762, are in clinical development in combination with cytotoxic agents for the treatment of solid tumors, including pancreatic cancers. To maximize the likelihood of their clinical success, it is essential to optimize drug scheduling as well as pharmacodynamic biomarkers in preclinical models. EXPERIMENTAL DESIGN: We tested multiple schedules of administration of gemcitabine and AZD7762 on the survival of pancreatic cancer cells. Potential pharmacodynamic biomarkers including pChk1, pChk2, pHistone H3, and caspase-3 were evaluated in vitro, followed by assessment of promising candidate biomarkers in vivo. We then went on to determine the contributions of PP2A and DNA damage to the mechanism(s) of induction of the identified biomarker, pS345 Chk1. RESULTS: AZD7762 given during and after or after gemcitabine administration produced maximum chemosensitization. In vivo, AZD7762 significantly inhibited the growth of pancreatic tumor xenografts in response to gemcitabine. Of the biomarkers assessed, pS345 Chk1 was most consistently increased in response to gemcitabine and AZD7762 in tumors and normal tissues (hair follicles). pS345 Chk1 induction in response to gemcitabine and AZD7762 occurred in the presence of PP2A inhibition and in association with elevated γH2AX, suggesting that DNA damage is an underlying mechanism. CONCLUSIONS: AZD7762 sensitizes pancreatic cancer cells and tumors to gemcitabine in association with induction of pS345 Chk1. Together these data support the clinical investigation of AZD7762 with gemcitabine in pancreatic cancer under a dosing schedule in which gemcitabine is administered concurrent with or before AZD7762 and in conjunction with skin biopsies to measure pS345 Chk1.


Assuntos
Desoxicitidina/análogos & derivados , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Tiofenos/farmacologia , Ureia/análogos & derivados , Animais , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quinase 1 do Ponto de Checagem , Dano ao DNA , Desoxicitidina/farmacologia , Histonas/metabolismo , Humanos , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Fosforilação/efeitos dos fármacos , Transplante Heterólogo , Ureia/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
19.
Chin Med J (Engl) ; 123(14): 1871-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20819570

RESUMO

BACKGROUND: Monolayer cell culture models are the traditional culture models used for in vitro research of pancreatic carcinoma chemosensitivity. However, these models neglect the interactions between tumor cells and the impact of the tumor microenvironment. Such tumor cell monolayers poorly mimic the solid tumor microenvironment. The present study aimed to investigate the chemosensitivity characteristics of pancreatic cancer cells in a three-dimensional culture system by analyzing the differences in drug sensitivity between a scattered cell culture model and a multicellular spheroid culture model. METHODS: Three pancreatic cancer cell lines (SW1990, ASPC-1 and PCT-3) were cultured in three-dimensional collagen gels as well as in traditional two-dimensional monolayers. The chemosensitivities of the pancreatic carcinoma cells to 5-fluorouracil (5-FU), gemcitabine, and oxaliplatin in vitro were detected by both the Cell Counting Kit-8 test and the collagen gel droplet-embedded culture drug-sensitivity test. RESULTS: In the two-dimensional culture model, differences in the chemosensitivities of the cloned pancreatic carcinoma cells and scattered cells existed for some concentrations of 5-FU, gemcitabine and oxaliplatin. In the three-dimensional culture model, there were significant differences in the chemosensitivities of the pancreatic cancer cells between the scattered cells and multicellular spheroids (P < 0.05). CONCLUSION: Pancreatic carcinoma cells exhibit multicellular resistance in three-dimensional cultures.


Assuntos
Antineoplásicos/farmacologia , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Fluoruracila/farmacologia , Humanos , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Neoplasias Pancreáticas/tratamento farmacológico , Esferoides Celulares/efeitos dos fármacos , Gencitabina
20.
Womens Health (Lond) ; 4: 11-22, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19072447

RESUMO

The management of breast cancer depends on the tumor and patient's characteristics. Anthracycline-based regimens have been proven to decrease the risk of relapse and prolong survival time in breast cancer. Taxanes have been incorporated not only into metastatic breast cancer but also into adjuvant regimens. Capecitabine, an oral fluoropyrimidine carbamate, has good single-agent activity and, together with docetaxel, demonstrated preclinical synergy and a survival benefit in metastatic breast cancer. Recent analyses show that capecitabine/docetaxel dosing flexibility for managing side effects does not compromise efficacy, and define this combination regimen as an important treatment option for its efficacy, tolerability and cost-effectiveness.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Taxoides/farmacologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Antineoplásicos/economia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Neoplasias da Mama/psicologia , Capecitabina , Análise Custo-Benefício , Desoxicitidina/economia , Desoxicitidina/farmacologia , Docetaxel , Feminino , Fluoruracila/economia , Fluoruracila/farmacologia , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxoides/economia , Trastuzumab
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