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1.
Mol Pharm ; 15(8): 3260-3271, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-29944378

RESUMO

Aberrant expression of the RON receptor tyrosine kinase, a cell surface protein, is a pathogenic feature in pancreatic cancer, which renders it a drug target for targeted therapy. Nevertheless, development of therapeutics targeting RON for pancreatic cancer therapy is hampered due to the lack of full addiction by pancreatic cancer cells to RON signaling for growth and survival. Here we describe a novel strategy using anti-RON antibody-directed drug delivery in the form of an antibody-drug conjugate for inhibition and/or eradication of pancreatic cancers. Monoclonal antibody Zt/g4 specific to the RON Sema domain was selected as the drug carrier based on its ability to induce robust RON internalization. Conjugation of Zt/g4 with monomethyl auristatin E, designated as Zt/g4-MMAE, was achieved through a protease-sensitive dipeptide linker to reach a drug to antibody ratio of 3.29:1. Zt/g4-MMAE was stable in human plasma with a dissociation rate less than 4% within a 10 day period. In vitro, Zt/g4-MMAE rapidly induced RON internalization, resulting in cell cycle arrest followed by massive cell death. The maximal effect was seen in pancreatic cancer cells with more than 10 000 receptor molecules per cell. Zt/g4-MMAE also synergized in vitro with chemotherapeutics including gemcitabine, 5-fluorouracil, and oxaliplatin to further reduce PDAC cell viability. In vivo, Zt/g4-MMAE exerts a long-lasting activity, which not only inhibited but also eradicated pancreatic xenograft tumors. These finding indicate that Zt/g4-directed drug delivery is highly effective for eradicating pancreatic tumors. Thus, Zt/g4-MMAE is a novel biotherapeutic with potential for therapy of RON-expressing pancreatic malignancies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Imunoconjugados/farmacologia , Oligopeptídeos/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Portadores de Fármacos/farmacologia , Portadores de Fármacos/uso terapêutico , Sinergismo Farmacológico , Feminino , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Humanos , Imunoconjugados/uso terapêutico , Camundongos , Camundongos Nus , Oligopeptídeos/uso terapêutico , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
2.
Bioorg Med Chem Lett ; 26(12): 2829-2833, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27156773

RESUMO

Ethacrynic acid (EA), a known inhibitor of the neoplastic marker glutathione S-transferase P1 and other GSTs, exerts a weak antiproliferative activity against human cancer cells. The clinical use of EA (Edecrin) as an anticancer drug is limited by its potent loop diuretic activity. In this study, we developed a non-diuretic 2-amino-2-deoxy-d-glucose conjugated EA (EAG) to target tumors cells via the highly expressed glucose transporter 1 (GLUT1). Cell survival assays revealed that EAG had little effect on normal cells, but was cytotoxic 3 to 4.5-fold greater than EA. Mechanistically, the EAG induced selective cell death in cancer cells by inhibiting GSTP1 and generating abundant reactive oxygen species. Furthermore, EAG induced p21(cip1) expression and a G2/M cell cycle block irrespective of the p53 gene status in tumor cells. These data encourage the development of new EA analogs.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Ácido Etacrínico/farmacologia , Glucosamina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Ácido Etacrínico/síntese química , Glucosamina/análogos & derivados , Glucosamina/química , Glutationa S-Transferase pi/antagonistas & inibidores , Glutationa S-Transferase pi/metabolismo , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
3.
Tumour Biol ; 35(2): 1671-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24085358

RESUMO

The rate of direct smoking, second hand smoking, and smokeless tobacco users as well as the amount of environmental pollutant like polycyclic aromatic hydrocarons is increasing in Bangladesh. Therefore, the prevalence of lung cancer is increasing day by day. To the best of our knowledge, no pharmacogentic study of CYP3A4, CYP3A5 genes has been reported on Bangladeshi population relating those with lung cancer. The present study was conducted to determine the association of CYP3A4, CYP3A5 gene polymorphisms and tobacco smoking in the development of lung cancer in Bangladeshi population. A case-control study was carried out on 106 lung cancer patients and 116 controls to investigate three allelic variants-CYP3A4*1B, CYP3A5*3, and CYP3A5*6 using Polymerase Chain Reaction Restriction Fragment Length Polymorphism. Risk of lung cancer was estimated as odds ratio (OR) and 95 % confidence interval (CI) using unconditional logistic regression models. The variant allele frequencies for CYP3A4*1B (*1A/*1B + *1B/*1B) were 2.83 % and 0.86 % and that of CYP3A5*3 (*1A/*3 + *3/*3) were 88.68 % and 85.34 % in cases and controls, respectively. Individual carrying at least one variant allele of CYP3A4*1B (CYP3A4*1A/1B + *1B/1B) has a 3.35 times more risk (OR = 3.35, 95 % Cl = 0.34-32.71, p = 0.271) for developing lung cancer whereas individual carrying at least one variant allele of CYP3A5 (CYP3A5*1A/3 + *3/3) has a 1.26 times more risk (OR = 1.35, 95 % Cl = 0.61-2.97) and both are statistically non-significant (p > 0.05). CYP3A5*6 was absent in the study population. No association of lung cancer with the mentioned polymorphisms was found both in heavy and light smokers. In the cases of all three major types of lung cancer-squamous cell carcinoma, adenocarcinoma, and small cell carcinoma-significantly strong relationships (p ˂ 0.05) have been found. To confirm the association of lung cancer with the mentioned polymorphisms, large number volunteers (patients and controls) will be required.


Assuntos
Citocromo P-450 CYP3A/genética , Predisposição Genética para Doença , Neoplasias Pulmonares/genética , Adulto , Idoso , Povo Asiático , Bangladesh , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar
4.
Int J Clin Pharmacol Ther ; 50(6): 452-8, 2012 06.
Artigo em Inglês | MEDLINE | ID: mdl-22677307

RESUMO

OBJECTIVE: Although several generic oral formulations of azithromycin (AZT; CAS 83905-01-5) are available in Bangladesh, information regarding the bioavailability of these formulations in the Bangladeshi population is unavailable. The purpose of this study was to compare the relative bioavailability and other pharmacokinetic properties of 2 formulations of AZT 500 mg tablet, namely Azomac® (General Pharmaceutical Ltd., Bangladesh) (Test formulation) and Zithromax® (Pfizer, Rome, Italy) (Reference product) and to evaluate whether these formulations meet the FDA criteria to assume bioequivalence in Bangladeshi volunteers. MATERIALS AND METHODS: A randomized, single-dose, two-way, cross-over, open-label pharmacokinetic study was performed in 24 healthy volunteers after administration of single dose of AZT 500 mg tablet under fasting condition following a washout period of 3 weeks. Blood samples were collected at pre-determined time points and analyzed for serum AZT concentration using a validated liquid chromatography-tandem mass spectrometry method. The pharmacokinetic parameters were determined by a noncompartmental method. RESULTS: From serum data, the obtained values given as mean (SD) for test and reference products were 382.41 (21.96), 392.31 (18.77) ng/ml for Cmax; 4.83(1.03), 4.83(1.03) h for tmax; 5,646.29 (912.19), 6,293.30 (966.76) h×ng/ml for AUC0-120; and 6,307.50 (863.40), 7,022.54 (961.28) h×ng/ml for AUC0-∞, respectively. The mean t1/2 was 41.44 (7.01), 41.16 (6.38) h for Test formulation and Reference product, respectively. The analysis of variance revealed no period or sequence effect for any pharmacokinetic property; however, a significant formulation effect was observed for Cmax, AUC0-120, AUC0-∞ and AUMC0-120. The 90% confidence intervals of the test/ reference mean ratios of the ln-transformed Cmax, AUC0-120 and AUC0-∞ were 87.89 - 89.36%, 87.40 - 91.70% and 87.47 - 92.07%, respectively, which fell within the predetermined FDA bioequivalence range. CONCLUSION: It can be concluded that the test formulation met the regulatory criteria for bioequivalence to the Reference tablet formulation in terms of both rate and extent of absorption.


Assuntos
Antibacterianos/farmacocinética , Azitromicina/farmacocinética , Adulto , Área Sob a Curva , Estudos Cross-Over , Humanos , Masculino , Comprimidos , Equivalência Terapêutica , Adulto Jovem
5.
Front Immunol ; 11: 164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161584

RESUMO

Phenotyping of immune cell subsets in clinical trials is limited to well-defined phenotypes, due to technological limitations of reporting flow cytometry multi-dimensional phenotyping data. We developed a multi-dimensional phenotyping analysis tool and applied it to detect nitric oxide (NO) levels in peripheral blood immune cells before and after adjuvant ipilimumab co-administration with a peptide vaccine in melanoma patients. We analyzed inhibitory and stimulatory markers for immune cell phenotypes that were felt to be important in the NO analysis. The pipeline allows visualization of immune cell phenotypes without knowledge of clustering techniques and to categorize cells by association with relapse-free survival (RFS). Using this analysis, we uncovered the potential for a dichotomous role of NO as a pro- and anti-melanoma factor. NO was found in subsets of immune-suppressor cells associated with shorter-term (≤ 1 year) RFS, whereas NO was also present in immune-stimulatory effector cells obtained from patients with significant longer-term (> 1 year) RFS. These studies provide insights into the cell-specific immunomodulatory role of NO. The methods presented herein can be applied to monitor the pro- and anti-tumor effects of a variety of immune-based therapeutics in cancer patients. Clinical Trial Registration Number: NCT00084656 (https://clinicaltrials.gov/ct2/show/NCT00084656).


Assuntos
Citometria de Fluxo/métodos , Imunoterapia/métodos , Leucócitos Mononucleares/imunologia , Melanoma/imunologia , Melanoma/terapia , Óxido Nítrico/metabolismo , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/terapia , Adulto , Idoso , Antineoplásicos Imunológicos/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Feminino , Humanos , Imunidade , Ipilimumab/uso terapêutico , Masculino , Melanoma/sangue , Pessoa de Meia-Idade , Óxido Nítrico/imunologia , Fenótipo , Neoplasias Cutâneas/sangue , Vacinas de Subunidades Antigênicas/uso terapêutico , Adulto Jovem
6.
Biomed Res Int ; 2018: 4010629, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29651429

RESUMO

Glioblastoma multiforme (GBM) is one of the most devastating brain tumors with median survival of one year and presents unique challenges to therapy because of its aggressive behavior. Current treatment strategy involves surgery, radiotherapy, immunotherapy, and adjuvant chemotherapy even though optimal management requires a multidisciplinary approach and knowledge of potential complications from both the disease and its treatment. Thymoquinone (TQ), the main bioactive component of Nigella sativa L., has exhibited anticancer effects in numerous preclinical studies. Due to its multitargeting nature, TQ interferes in a wide range of tumorigenic processes and counteract carcinogenesis, malignant growth, invasion, migration, and angiogenesis. TQ can specifically sensitize tumor cells towards conventional cancer treatments and minimize therapy-associated toxic effects in normal cells. Its potential to enter brain via nasal pathway due to volatile nature of TQ adds another advantage in overcoming blood-brain barrier. In this review, we summarized the potential role of TQ in different signaling pathways in GBM that have undergone treatment with standard therapeutic modalities or with TQ. Altogether, we suggest further comprehensive evaluation of TQ in preclinical and clinical level to delineate its implied utility as novel therapeutics to combat the challenges for the treatment of GBM.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/uso terapêutico , Benzoquinonas/farmacocinética , Benzoquinonas/uso terapêutico , Neoplasias Encefálicas , Glioblastoma , Animais , Benzoquinonas/química , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Nigella sativa/química
7.
Front Pharmacol ; 8: 295, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659794

RESUMO

Thymoquinone (TQ), the main bioactive component of Nigella sativa, has been found to exhibit anticancer effects in numerous preclinical studies. Due to its multitargeting nature, TQ interferes in a wide range of tumorigenic processes and counteracts carcinogenesis, malignant growth, invasion, migration, and angiogenesis. Moreover, TQ can specifically sensitize tumor cells toward conventional cancer treatments (e.g., radiotherapy, chemotherapy, and immunotherapy) and simultaneously minimize therapy-associated toxic effects in normal cells. In this review, we summarized the adjuvant potential of TQ as observed in various in vitro and in vivo animal models and discussed the pharmacological properties of TQ to rationalize its supplementary role in potentiating the efficacy of standard therapeutic modalities namely surgery, radiotherapy, chemotherapy, and immunotherapy. Altogether, we suggest further comprehensive evaluation of TQ in preclinical and clinical levels to delineate its implied utility as a novel complementary adjuvant therapy for cancer treatment.

8.
Biomolecules ; 7(2)2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28346397

RESUMO

Central nervous system tumors comprising the primary cancers and brain metastases remain the most lethal neoplasms and challenging to treat. Substantial evidence points to a paramount role for inflammation in the pathology leading to gliomagenesis, malignant progression and tumor aggressiveness in the central nervous system (CNS) microenvironment. This review summarizes the salient contributions of oxidative stress, interleukins, tumor necrosis factor-α (TNF-α), cyclooxygenases, and transcription factors such as signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-κB) and the associated cross-talks to the inflammatory signaling in CNS cancers. The roles of reactive astrocytes, tumor associated microglia and macrophages, metabolic alterations, microsatellite instability, O6-methylguanine DNA methyltransferase (MGMT) DNA repair and epigenetic alterations mediated by the isocitrate dehydrogenase 1 (IDH1) mutations have been discussed. The inflammatory pathways with relevance to the brain cancer treatments have been highlighted.


Assuntos
Neoplasias Encefálicas/patologia , Carcinogênese , Animais , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/imunologia , Citocinas/metabolismo , Humanos , Inflamação/complicações , Macrófagos/imunologia , Microambiente Tumoral
9.
J Altern Complement Med ; 19(9): 767-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23581458

RESUMO

OBJECTIVE: A randomized, single-center, double-blind, crossover clinical trial investigated the effects of an herbal preparation containing Vernonia cinerea in patients with type 2 diabetes mellitus. METHODS: 48 patients with type 2 diabetes mellitus for longer than 6 months were divided into two groups matched for demographic and paraclinical variables. One group received a standard preparation of V. cinerea for 3 months, followed by placebo for another 3 months, and the other group received treatment in the reverse order. All patients received detailed advice on diet, exercise, and lifestyle modification. Glucose level was documented every 2 weeks, and hemoglobin A1c, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, and creatinine levels were determined at recruitment, 3 months, and study completion at 6 months. RESULTS: Glucose, hemoglobin A1c, cholesterol, LDL cholesterol, and triglyceride levels decreased significantly in both groups. No significant differences were seen in aspartate aminotransferase, alanine aminotransferase, or creatinine levels, indicating that use of the herbal preparation had no adverse effect on liver or renal function. CONCLUSION: Herbal treatment with V. cinerea has a beneficial effect on reducing the glycemic state in patients with type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Preparações de Plantas/uso terapêutico , Vernonia , Adulto , Idoso , Glicemia/análise , Estudos Cross-Over , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/análise , Humanos , Lipídeos/sangue , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Placebos , Resultado do Tratamento
10.
Clin Chim Acta ; 416: 11-9, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23178447

RESUMO

BACKGROUND: CYP1A1, CYP2A6 and CHRNA5 are biologically plausible genes as risk factors for lung cancer but no studies have been reported in the Bangladeshi population. METHODS: We conducted this study to determine the prevalence and role of CYP1A1, CYP2A6 and CHRNA5 polymorphisms together with tobacco smoking in the development of lung cancer in Bangladesh. A case-control study was carried out on 106 lung cancer patients and 116 controls to investigate three allelic variants of the CYP1A1 gene-rs4646903, rs1048943 and rs1799814; 2 variants of CYP2A6 (CYP2A6*1B1, CYP2A6*4) and 1 variant of CHRNA5 (rs16969968) using Polymerase Chain Reaction Restriction Fragment Length Polymorphism. RESULTS: Lung cancer risk was estimated as odds ratio (OR) and 95% confidence interval (CI) using unconditional logistic regression models adjusting for age, sex and smoking. A significantly elevated lung cancer risk was associated with heterozygous, mutant and combined heterozygous plus mutant variants of CYP1A1 rs4646903. A significant association was also found for heterozygous and heterozygous plus mutant variants of rs1048943 which was in linkage disequilibrium with rs4646903. The risk of lung cancer was decreased significantly in individuals carrying at least one CYP2A6 deletion (CYP2A6*4) allele. No association with lung cancer risk was found for CHRNA5 rs16969968. When stratified by smoking, the effects of CYP1A1 and CYP2A6 polymorphisms on lung cancer susceptibility were found to be significant only in heavy smokers who had smoked 40 pack years or more (54% of all cases) but no associations were seen for lighter smokers. No association was also found with any polymorphism in the non-smokers in this study. CONCLUSIONS: Our results indicate that the CYP1A1*2B allele (rs4646903 and rs1048943) is associated with an increased lung cancer risk and CYP2A6*4 is associated with a decreased lung cancer risk in the study population.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Citocromo P-450 CYP1A1/genética , Neoplasias Pulmonares/genética , Receptores Nicotínicos/genética , Bangladesh/epidemiologia , Estudos de Casos e Controles , Citocromo P-450 CYP2A6 , Predisposição Genética para Doença , Variação Genética , Humanos , Reação em Cadeia da Polimerase , Polimorfismo Genético , Fatores de Risco , Fumar
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