Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Elife ; 112022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35815945

RESUMO

Immunometabolic reprogramming due to adenosine produced by CD73 (encoded by the 5'-ectonucleotidase gene NT5E) is a recognized immunosuppressive mechanism contributing to immune evasion in solid tumors. Adenosine is not only known to contribute to tumor progression, but it has specific roles in driving dysfunction of immune cells, including natural killer (NK) cells. Here, we engineered human NK cells to directly target the CD73-adenosine axis by blocking the enzymatic activity of CD73. In doing so, the engineered NK cells not only impaired adenosinergic metabolism driven by the hypoxic uptake of ATP by cancer cells in a model of non-small-cell lung cancer, but also mediated killing of tumor cells due to the specific recognition of overexpressed CD73. This resulted in a 'single agent' immunotherapy that combines antibody specificity, blockade of purinergic signaling, and killing of targets mediated by NK cells. We also showed that CD73-targeted NK cells are potent in vivo and result in tumor arrest, while promoting NK cell infiltration into CD73+ tumors and enhancing intratumoral activation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adenosina/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Humanos , Imunoterapia/métodos , Células Matadoras Naturais , Neoplasias Pulmonares/metabolismo
2.
Sci Rep ; 7(1): 11551, 2017 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-28912423

RESUMO

Posttraumatic stress disorder (PTSD) gains a lot of attention due to high prevalence and strong psychological upset, but the etiology remains undefined and effective treatment is quite limited. Growing studies demonstrated the involvement of oxidative stress in various psychiatry diseases, suggesting anti-oxidation therapy might be a strategy for PTSD treatment. Free and Easy Wanderer (FAEW) is a poly-herbal drug clinically used in China for hundreds of years in the treatment of psychiatric disorder. We hypothesized that FAEW exerts clinical effects through the activity against oxidative stress with fluoxetine as antidepressant control drug. Our results revealed that FAEW significantly reduced both endogenous and H2O2-induced exogenous ROS levels in the human glioblastoma T98G and neuroblastoma SH-SY5Y cell lines. Transcriptome-wide microarray analysis indicated NRF2/HO-1 as the common target of FAEW and fluoxetine. Western blotting assay proved that the two drugs promoted NRF2 release from KEAP1 in the cytoplasm and translocation to the nuclei in a KEAP1-dependent manner, the expression of the protein HO-1 increased accordingly, suggesting the participation of KEAP1-NRF2/HO-1 pathway. The chemical constituents of FAEW (i.e. paeoniflorin, baicalin) bound to KEAP1 in silico, which hence might be the effective substances of FAEW. In conclusion, FAEW counteracted H2O2-induced oxidative stress through KEAP1-NRF2/HO-1 pathway.


Assuntos
Antioxidantes/farmacologia , Heme Oxigenase-1/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Linhagem Celular , Perfilação da Expressão Gênica , Humanos , Análise em Microsséries , Neurônios/efeitos dos fármacos , Plantas Medicinais
3.
Sci Rep ; 6: 36754, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27824156

RESUMO

We systematically characterised multifactorial multidrug resistance (MDR) in CEM/ADR5000 cells, a doxorubicin-resistant sub-line derived from drug-sensitive, parental CCRF-CEM cells developed in vitro. RNA sequencing and network analyses (Ingenuity Pathway Analysis) were performed. Chromosomal aberrations were identified by array-comparative genomic hybridisation (aCGH) and multicolour fluorescence in situ hybridisation (mFISH). Fifteen ATP-binding cassette transporters and numerous new genes were overexpressed in CEM/ADR5000 cells. The basic karyotype in CCRF-CEM cells consisted of 47, XX, der(5)t(5;14) (q35.33;q32.3), del(9) (p14.1), +20. CEM/ADR5000 cells acquired additional aberrations, including X-chromosome loss, 4q and 14q deletion, chromosome 7 inversion, balanced and unbalanced two and three way translocations: t(3;10), der(3)t(3;13), der(5)t(18;5;14), t(10;16), der(18)t(7;18), der(18)t(21;18;5), der(21;21;18;5) and der(22)t(9;22). CCRF-CEM consisted of two and CEM/ADR5000 of five major sub-clones, indicating genetic tumor heterogeneity. Loss of 3q27.1 in CEM/ADR5000 caused down-regulation of ABCC5 and ABCF3 expression, Xq28 loss down-regulated ABCD1 expression. ABCB1, the most well-known MDR gene, was 448-fold up-regulated due to 7q21.12 amplification. In addition to well-known drug resistance genes, numerous novel genes and genomic aberrations were identified. Transcriptomics and genetics in CEM/AD5000 cells unravelled a range of MDR mechanisms, which is much more complex than estimated thus far. This may have important implications for future treatment strategies.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Genoma , Leucemia/genética , Leucemia/metabolismo , Transcriptoma , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Hibridização Genômica Comparativa , Reparo do DNA , Regulação para Baixo , Perfilação da Expressão Gênica , Genômica , Humanos , Hibridização in Situ Fluorescente , Leucemia/tratamento farmacológico , Proteínas de Neoplasias/genética , Análise de Sequência de RNA , Translocação Genética
4.
Anticancer Res ; 36(1): 279-86, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26722054

RESUMO

BACKGROUND: While cancer epidemiology is well-investigated in developed countries, the cancer burden in Africa is less well documented. We provide cancer statistics of 33,201 patients from all Sudan diagnosed at the Radiation and Isotope Centre in Khartoum (RICK). This hospital covers approximately 80% of patients with cancer in Sudan and is, therefore, considered representative for the situation in this country. MATERIALS AND METHODS: Data from 2009-2013 were collected at RICK. Cancer diagnoses were made by standard pathological and radiological methods. Epidemiological data were categorized by age, gender, resident state, marital status etc. and subjected to statistical analyses by SPSS 21v. RESULTS: The cancer prevalence rate per year was 5,000-7,000 among adults and 300-400 among children, with increasing tendency for adults. Male:female ratios were 1:1.18 for adults and 1.46:1 for children. The five most frequent tumour types were breast cancer, leukaemia, prostatic carcinoma, lymphoma and colorectal carcinoma in adults and leukaemia, lymphoma, eye tumours, sarcoma and brain tumours in children. Remarkably, the median age of cancer diagnosis was 10-20 years higher in men than in women, mainly due to earlier onset of gender-related tumours in females (cancer of breast, cervix, or ovary) than in men (prostatic carcinoma). Chronic myeloid leukaemia was the most frequent haematopoietic malignancy in adults and acute lymphoblastic leukaemia in children. Comparing cancer cases with population numbers of Sudanese states, Northern Sudan, River Nile and Khartoum revealed up to 8-fold higher cancer incidence rates than Al Gedarif, Southern Dafur and Blue Nile. The other states had intermediate incidence rates. Interestingly, oesophageal carcinoma occurred proportionally more frequently in Kassala (rank 3) than in the entire Sudan (rank 7) or other states. CONCLUSION: This is the largest survey on cancer burden in Sudan. It may serve as basis for governmental programmes for assessing risk factors, improving cancer prevention (e.g. by educational and vaccination programmes) and cancer therapy in the future.


Assuntos
Neoplasias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Prevalência , Sudão , Inquéritos e Questionários , Adulto Jovem
5.
Target Oncol ; 10(3): 337-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25410594

RESUMO

Epidermal growth factor receptors (EGFR, HER2, HER3) activate signal transduction pathways involved in cancer proliferation, apoptosis, differentiation, metastasis, and angiogenesis. Their overexpression and activation are associated with unfavorable prognosis of cancer patients. Therefore, they are attractive targets for cancer therapy. Due to the development of drug resistance, therapeutic monoclonal antibodies and synthetic small molecule tyrosine kinase inhibitors directed against EGFR family members may fail with fatal consequences for cancer patients. Medicinal plants raised considerable interest during the past years as valuable resources to develop novel treatment therapies targeting epidermal growth factor receptors and their downstream signal transduction pathways. The present review gives an overview of isolated phytochemicals that inhibit these signaling routes. Inhibitors have been described that down-regulate the mRNA or protein expression of EGFR, HER2, or HER3 or inhibit the phosphorylation of these receptors and/or their downstream signaling kinases. Remarkably, a wealth of in vivo experiments complemented in vitro data, indicating that natural products are also active in living animals bringing this research concept closer to clinical applicability. The combination of receptor-inhibiting natural product with standard anticancer drugs frequently caused increased or even synergistic tumor inhibition in vitro and in vivo. It deserves further evaluation, if and how epidermal growth factor receptor-targeting natural products can be integrated into clinical oncology as well as to define their role for more tumor-specific and individualized tumor therapies.


Assuntos
Receptores ErbB/antagonistas & inibidores , Neoplasias/genética , Neoplasias/terapia , Fitoterapia/métodos , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Análise Mutacional de DNA , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/metabolismo , Humanos , Oncologia/métodos , Oncologia/tendências , Camundongos , Simulação de Acoplamento Molecular , Fosforilação , Compostos Fitoquímicos/química , Plantas Medicinais/química , RNA Mensageiro/metabolismo
6.
J Org Chem ; 80(2): 836-46, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25517288

RESUMO

A systematic study of the biomimetic pathways to yezo'otogirin C under aerobic and anaerobic conditions has been investigated, and both are found to be feasible pathways to the natural product depending on the physiological conditions. Because of the lower activation energy, the aerobic process would be more favorable when the in vivo oxygen level is high. In the course of this study, a highly efficient synthetic route to (±)-yezo'otogirin C has been established in four steps (31% overall yield) from a readily available compound without using any protecting groups. The natural product and its structural analogues exhibited antitumor activities against several human cancer cell lines and appeared to arrest cell cycles in different phases.


Assuntos
Antineoplásicos/química , Antineoplásicos/síntese química , Materiais Biomiméticos/síntese química , Terpenos/química , Terpenos/síntese química , Materiais Biomiméticos/química , Linhagem Celular Tumoral , Humanos , Estereoisomerismo
7.
Eur J Med Chem ; 87: 413-20, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25282264

RESUMO

A series of cationic polymers based on low generation (G1) peptide dendrimer were synthesized with disulfide-containing linkages. The DNA binding abilities of the target polymers were studied by gel electrophoresis and fluorescence quenching assay. The bioreducible property of the disulfide-containing polymers P2 and P3 was also investigated in the presence of dithiothreitol (DTT). Results from dynamic light scattering (DLS) and transmission electron microscopy (TEM) assays reveal that these materials may condense DNA into nanoparticles with proper sizes and zeta-potentials. In vitro cell experiments show that compared to branched 25 KDa PEI, P2 and P3 may exhibit much higher gene transfection efficiency and lower cytotoxicity in both HEK293 and U-2OS cells. Additionally, polymer prepared from Michael addition gives better gene transfection ability, while polymer prepared from ring-opening reaction has better serum tolerance. Results indicate that these polymers might be promising non-viral gene vectors for their easy preparation, very low cytotoxicity, and good transfection efficiency.


Assuntos
Dendrímeros/química , Portadores de Fármacos/química , Peptídeos/química , Transfecção , Linhagem Celular Tumoral , DNA/genética , DNA/metabolismo , Portadores de Fármacos/metabolismo , Portadores de Fármacos/toxicidade , Células HEK293 , Humanos , Peptídeos/metabolismo , Peptídeos/toxicidade , Relação Estrutura-Atividade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA