37 research outputs found

    Comparison of Effects of the Ethanolic Extracts of Brazilian Propolis on Human Leukemic Cells As Assessed with the MTT Assay

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    Propolis is a resinous product collected by honey bees. It was also reported that propolis has a wide variety of biological actions, including antimicrobial activity and antioxidant, anti-inflammatory, and suppressive effects of dioxin toxicity activities. The aim of this study was to compare the in vitro cytotoxic activities of green propolis (G12) and red propolis (G13) in human leukemia cells. These cells were incubated with different concentrations of propolis and 48 hours after the IC50 was calculated for each cell. The results showed that the red propolis has cytotoxic effect in vitro higher than green propolis. Red propolis was showed to be cytostatic in K562 cells and caused the same amount of apoptosis as its control Gleevec. In conclusion, these results showed that red propolis is more cytotoxic than the green propolis in a variety of human cell lines of leukemia. Red propolis may contain drugs capable of inhibiting cancer cell growth. Therefore, further isolation of respective chemical ingredients from the red propolis (G13) for identification of the activities is necessary

    Synthesis, characterization and in vitro anticancer activity of Novel 8,4’ : oxyneolignan analogues

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    Neolignans are a class of natural products with a wide range of biological effects. These substances are of great synthetic and biological interest, especially in searching for novel anticancer agents. In this paper, we report the synthesis of a new subclass of 8,4’-oxyneolignan analogues (β-ketoethers and β-ketoesters) and their cell viability assay on twenty four different cancer cells, among leukemias and carcinomas. Three compounds inhibited the growth of most human cancer cells. 2-Oxo-2-phenylethyl(2E)-3-[4-(2-oxo-2-phenylethoxy) phenyl]prop-2-enoate showed an antiproliferative activity superior to doxorubicin for U-87, U-138 MG and H1299 cell types and (E)-2-oxo-2-phenylethyl 3-(3-methoxy-4-(2-oxo-2-phenylethoxy)phenyl)acrylate was found to be very selective, demonstrating a growth inhibition of 92.0% against KG-1 cells. Furthermore, 1-oxo-1-phenylpropan-2-yl cinnamate exhibited significant inhibition activity in a range of 52.2 to 91.2% against twelve kinds of leukemia cell lines, revealing excellent results and very comparable to the reference drug

    SB225002 induces cell death and cell cycle arrest in acute lymphoblastic leukemia cells through the activation of GLIPR1

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    Acute Lymphoblastic Leukemia (ALL) is the most frequent childhood malignancy. In the effort to find new anti-leukemic agents, we evaluated the small drug SB225002 (N-(2-hydroxy-4-nitrophenyl)-N'-(2-bromophenyl)urea). Although initially described as a selective antagonist of CXCR2, later studies have identified other cellular targets for SB225002, with potential medicinal use in cancer. We found that SB225002 has a significant pro-apoptotic effect against both B- and T-ALL cell lines. Cell cycle analysis demonstrated that treatment with SB225002 induces G2-M cell cycle arrest. Transcriptional profiling revealed that SB225002-mediated apoptosis triggered a transcriptional program typical of tubulin binding agents. Network analysis revealed the activation of genes linked to the JUN and p53 pathways and inhibition of genes linked to the TNF pathway. Early cellular effects activated by SB225002 included the up-regulation of GLIPR1 , a p53-target gene shown to have pro-apoptotic activities in prostate and bladder cancer. Silencing of GLIPR1 in B- and T-ALL cell lines resulted in increased resistance to SB225002. Although SB225002 promoted ROS increase in ALL cells, antioxidant N-Acetyl Cysteine pre-treatment only modestly attenuated cell death, implying that the pro-apoptotic effects of SB225002 are not exclusively mediated by ROS. Moreover, GLIPR1 silencing resulted in increased ROS levels both in untreated and SB225002-treated cells. In conclusion, SB225002 induces cell cycle arrest and apoptosis in different B- and T-ALL cell lines. Inhibition of tubulin function with concurrent activation of the p53 pathway, in particular, its downstream target GLIPR1 , seems to underlie the anti-leukemic effect of SB225002

    Human eosinophil adhesion and degranulation stimulated with eotaxin and RANTES in vitro: Lack of interaction with nitric oxide

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    <p>Abstract</p> <p>Background</p> <p>Airway eosinophilia is considered a central event in the pathogenesis of asthma. The toxic components of eosinophils are thought to be important in inducing bronchial mucosal injury and dysfunction. Previous studies have suggested an interaction between nitric oxide (NO) and chemokines in modulating eosinophil functions, but this is still conflicting. In the present study, we have carried out functional assays (adhesion and degranulation) and flow cytometry analysis of adhesion molecules (VLA-4 and Mac-1 expression) to evaluate the interactions between NO and CC-chemokines (eotaxin and RANTES) in human eosinophils.</p> <p>Methods</p> <p>Eosinophils were purified using a percoll gradient followed by immunomagnetic cell separator. Cell adhesion and degranulation were evaluated by measuring eosinophil peroxidase (EPO) activity, whereas expression of Mac-1 and VLA-4 was detected using flow cytometry.</p> <p>Results</p> <p>At 4 h incubation, both eotaxin (100 ng/ml) and RANTES (1000 ng/ml) increased by 133% and 131% eosinophil adhesion, respectively. L-NAME alone (but not D-NAME) also increased the eosinophil adhesion, but the co-incubation of L-NAME with eotaxin or RANTES did not further affect the increased adhesion seen with chemokines alone. In addition, L-NAME alone (but not D-NAME) caused a significant cell degranulation, but it did not affect the CC-chemokine-induced cell degranulation. Incubation of eosinophils with eotaxin or RANTES, in absence or presence of L-NAME, did not affect the expression of VLA-4 and Mac-1 on eosinophil surface. Eotaxin and RANTES (100 ng/ml each) also failed to elevate the cyclic GMP levels above baseline in human eosinophils.</p> <p>Conclusion</p> <p>Eotaxin and RANTES increase the eosinophil adhesion to fibronectin-coated plates and promote cell degranulation by NO-independent mechanisms. The failure of CC-chemokines to affect VLA-4 and Mac-1 expression suggests that changes in integrin function (avidity or affinity) are rather involved in the enhanced adhesion.</p

    CAR T cells generated using sleeping beauty transposon vectors and expanded with an EBV-transformed lymphoblastoid cell line display antitumor activity in vitro and in vivo

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    Chimeric antigen receptor (CAR) T cell immunotherapy for the treatment of cancer is now an approved treatment for B cell malignancies. However, the use of viral vectors to provide long-term CAR expression is associated with high production costs and cumbersome quality controls, impacting the final cost of CAR T cell therapies. Nonviral integrative vectors, such as Sleeping Beauty (SB) transposons, provide an alternative to modify primary T cells. Therefore, we developed a protocol to expand SB-transfected 19BB zeta CAR T cells using a lymphoblastoid cell line, and evaluated T cell phenotype as well as function along the T cell expansion. Electroporation of PBMCs with transposon plasmid decreased cell viability on day 1 but had a minor impact on the frequency of memory subpopulations when compared to mock condition. CAR+ lymphocytes showed increased proliferation compared to mock control and high cytotoxic activity towards CD19+ cells without significant differences in exhaustion markers expression. Moreover, CAR+ lymphocytes showed an increased frequency by the end of the stimulation cycle compared with day 1, suggesting that CAR expression confers a selective proliferation advantage. Immunodeficient NOD scid gamma chain knockout (NSG) mice engrafted with the human pre-B leukemic cell line RS4;11 and treated with 19BB zeta CAR T cells showed improved overall survival when compared to mock T cells treated animals. The results showed that electroporation using the SB system is a simple and affordable method for inducing long-term CAR expression in T lymphocytes. Expansion of gene-modified T cells with the lymphoblastoid cell line provided up to 2 cycles of stimulations, generating effective T cells against leukemia in vitro and in vivo304511522CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informaçãosem informação2014/04412-4We would like to thank the Brazilian NationalCancer Institute (INCA) Blood Bank and He-motherapy Service for sample preparation and cellirradiation. Funding for this study was provided bythe Brazilian Ministry of Health, Brazilian Na-tional Cancer Institute (INCA), CNPq, CAPES,INCT Synthetic Biology (465603/2014-9), AryFrauzino Cancer Foundation (FAF), OncobiologyProgram - UFRJ, FAPESP (2014/04412-4

    ANKHD1, a novel component of the Hippo signaling pathway, promotes YAP1 activation and cell cycle progression in prostate cancer cells

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    ANKHD1 is a multiple ankyrin repeat containing protein, recently identified as a novel member of the Hippo signaling pathway. the present study aimed to investigate the role of ANKHDI in DU145 and LNCaP prostate cancer cells. ANKHD1 and YAP1 were found to be highly expressed in prostate cancer cells, and ANKHD1 silencing decreased cell growth, delayed cell cycle progression at the S phase, and reduced tumor xenograft growth. Moreover, ANKHD1 knockdown down-regulated YAP1 expression and activation, and reduced the expression of CCNA2, a YAP1 target gene. These findings indicate that ANKHD1 is a positive regulator of YAP1 and promotes cell growth and cell cycle progression through Cyclin A upregulation. (C) 2014 Elsevier Inc. All rights reserved.Univ Estadual Campinas, Hematol & Hemotherapy Ctr, Hemoctr, Inst Nacl Ciencia & Tecnol Sangue,UNICAMP, BR-13083878 Campinas, SP, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, São Paulo, BrazilUniv Estadual Campinas, Integrated Ctr Childhood Oncohematol Invest, BR-13083878 Campinas, SP, BrazilUniv São Paulo, Dept Internal Med, Ribeirao Preto Med Sch, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, São Paulo, BrazilWeb of Scienc

    TP53 p.Arg337His geographic distribution correlates with adrenocortical tumor occurrence

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    Abstract Background The p.Arg337His mutation of the TP53 is the most frequent germline missense variant associated with cancer described so far in this gene. It is mainly found in the South and Southeastern regions of Brazil, where it has been associated with a high incidence of pediatric adrenocortical (ACT) and choroid plexus tumors. The frequency and geographic distribution of this mutation is largely unknown, except for the Parana State, where a mean prevalence of 0.27% was reported. In the present study, we developed a high‐throughput method for p.Arg337His genotyping, what allowed us to determine the frequency and geographic distribution of this mutation in a cohort from the most populous state in Brazil. Methods Consecutive samples from 31,612 newborns from São Paulo State were screened for p.Arg337His. The allelic discrimination was done by real‐time polymerase chain reaction (PCR) and the presence of haplotype A3 in carriers was examined by using allele‐specific oligonucleotide PCR, followed by nested‐PCR to detect the SNP rs9894946. Results We found 67 (0.21%) samples positive for this mutation. The highest p.Arg337His frequencies were found in the cities close to the boundary between São Paulo and Minas Gerais State. No association could be found between p.Arg337His and gender, ethnicity, premature birth or twinning. Remarkably, a trend was found between the geographic distribution of p.Arg337His carriers and occurrence of ACT. Conclusion We presented for the first time the p.Arg337His frequency among individuals unselected for any disease from a subset of the São Paulo State, the most populous in Brazil. The allele discrimination assay we presented here has proven to be a reliable and efficient method for high‐throughput genotyping. ACT was found to be a good sentinel cancer to suppose p.Arg337His presence in our region

    Further drimane sesquiterpenes from Drimys brasiliensis stem barks with cytotoxic potential

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    Drimys brasiliensis Miers (Winteraceae) is used in folk medicine for the treatment of cancer. Its anti-tumor activity has been demonstrated in vitro models using extracts and isolated compounds. This study investigates the cytotoxic effects of stem bark extracts of D. brasiliensis as well as isolated compounds that may be responsible for the activitys and evaluates them in leukemia cells. The stem bark extract were subjected to column chromatography, and the structures of compounds were elucidated based on spectroscopic methods by using NMR and infrared spectroscopy and GC/MS. The cytotoxicity of the isolated compounds was evaluated in chronic myeloid (K562) and acute B lymphoblastic (Nalm6) leukemia cells using tetrazolium assay (MTT). Two new compounds were isolated 1 beta-O-p-methoxy-E-cinnamoyl-5 alpha-keto-11 alpha-enol-albicanol (1a) and the isomer 1 beta-O-p-methoxy-E-cinnamoyl-5 alpha-keto-11 beta-enol-albicanol (1b) and 1 beta-O-p-methoxy-E-cinnamoyl-isodrimeninol (2). The known compounds polygonal acid (3a) and the isomer isopolygonal acid (3b), fuegin (4a) and the isomer epifuegin (4b), the mixture drimanial (5) and 1 beta-O-(p-methoxy-E-cinnamoyl)-6 alpha-hydroxypolygodial (6) were also isolated. The drimanes (1-4) and drimanial (5), 1 beta-(p-coumaroyloxy)-polygodial (7), 1 beta-(p-methoxycinnamoyl)-polygodial (8), and polygodial (9) isolated previously were assessed in tumor cells. The IC50 values were between 3.56 and 128.91 mu M. 1-beta-(p-cumaroiloxi)-polygodial showed the best result with IC50 8.18 and 3.56 mu M by K562 and Nalm6, respectively. The chloroform extract of the stem bark of D. brasiliensis is a great source of drimane sesquiterpenes. Our experimental data suggest that drimanes are responsible for cytotoxicity activity demonstrated by this species, especially those with the aldehyde group linked to carbons C-11 and C-123897791797CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA E INOVAÇÃO DO ESTADO DE SANTA CATARINA - FAPESCsem informaçã

    Human eosinophil adhesion and degranulation stimulated with eotaxin and RANTES : Lack of interaction with nitric oxide-2

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    E methyl ester (L-NAME; 0.1 mM), eotaxin (EOT; 100 ng/ml) or RANTES (RAN; 100 ng/ml) for 4 h (37°C, 5%CO), and then were labelled with anti-α 4 (VLA-4; Panel A) or anti-αM (Mac-1; Panel B) antibodies. The results are expressed as mean fluorescence ± SEM (= 4).<p><b>Copyright information:</b></p><p>Taken from "Human eosinophil adhesion and degranulation stimulated with eotaxin and RANTES : Lack of interaction with nitric oxide"</p><p>http://www.biomedcentral.com/1471-2466/8/13</p><p>BMC Pulmonary Medicine 2008;8():13-13.</p><p>Published online 12 Aug 2008</p><p>PMCID:PMC2527293.</p><p></p
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