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Lines Used (line + used)
Kinds of Lines Used Selected AbstractsCombining adenoviral oncolysis with temozolomide improves cell killing of melanoma cellsINTERNATIONAL JOURNAL OF CANCER, Issue 12 2007Christina Quirin Abstract Oncolytic Adenoviruses are emerging agents for treatment of cancer by tumor-restricted virus replication, cell lysis and virus spread. Clinical studies with first generation oncolytic adenoviruses have revealed that an increased potency is warranted in order to achieve therapeutic efficacy. One approach towards this end is to combine adenoviral oncolysis with chemotherapy. Here, a fundamental requirement is that chemotherapy does not interfere with adenovirus replication in cancer cells. We have previously developed a melanoma-targeted oncolytic adenovirus, Ad5/3.2xTyr, which features tyrosinase promoter regulated replication and enhanced cell entry into melanoma cells. In this study, we investigated a combination treatment of melanoma cells with Ad5/3.2xTyr and temozolomide (TMZ), which produces the same active metabolite as Dacarbazine/DTIC, the standard chemotherapy for advanced melanoma. We report that TMZ does not inhibit adenovirus replication in melanoma cells. Additive or synergistic cell killing of melanoma cells, dependent on the cell line used, was observed. Enhanced cell binding was not responsible for synergism of adenoviral oncolysis and TMZ treatment. We rather observed that higher numbers of virus genomes are produced in TMZ-treated cells, which also showed a cell cycle arrest in the G2 phase. Our results have important implications for the clinical implementation of adenoviral oncolysis for treatment of malignant melanoma. It suggests that such studies are feasible in the presence of TMZ or DTIC chemotherapy and recommends the investigation of a viro-chemo combination therapy. © 2007 Wiley-Liss, Inc. [source] The influence of genetic background on resistance to the cabbage aphid (Brevicoryne brassicae) in Kale (Brassica oleracea var. acephala)ANNALS OF APPLIED BIOLOGY, Issue 3 2000N B KIFT Summary Resistance to Brevicoryne brassicae has been identified in the progeny of two selected kale (B. oleracea var. acephala) plants, one from the F1 hybrid cultivar ,Arsis RS' and one from the landrace ,Butzo'. These plants were crossed with susceptible B. oleracea morphotypes that have different periods to flowering. The type of susceptible plant line used had an effect on the resistance phenotypc of the progeny. Tested F2 populations derived from these crosses show that resistance is not under simple genetic control. This, in addition to variation in aphid numbers within accessions, suggests that separation of genetic components of control from environmental ,noise' for any accession may only be possible by the production of double haploid plant lines. [source] Highly efficient deletion of FUT8 in CHO cell lines using zinc-finger nucleases yields cells that produce completely nonfucosylated antibodiesBIOTECHNOLOGY & BIOENGINEERING, Issue 5 2010Laetitia Malphettes Abstract IgG1 antibodies produced in Chinese hamster ovary (CHO) cells are heavily ,1,6-fucosylated, a modification that reduces antibody-dependent cellular cytotoxicity (ADCC) and can inhibit therapeutic antibody function in vivo. Addition of fucose is catalyzed by Fut8, a ,1,6-fucosyltransferase. FUT8,/, CHO cell lines produce completely nonfucosylated antibodies, but the difficulty of recapitulating the knockout in protein-production cell lines has prevented the widespread adoption of FUT8,/, cells as hosts for antibody production. We have created zinc-finger nucleases (ZFNs) that cleave the FUT8 gene in a region encoding the catalytic core of the enzyme, allowing the functional disruption of FUT8 in any CHO cell line. These reagents produce FUT8,/, CHO cells in 3 weeks at a frequency of 5% in the absence of any selection. Alternately, populations of ZFN-treated cells can be directly selected to give FUT8,/, cell pools in as few as 3 days. To demonstrate the utility of this method in bioprocess, FUT8 was disrupted in a CHO cell line used for stable protein production. ZFN-derived FUT8,/, cell lines were as transfectable as wild-type, had similar or better growth profiles, and produced equivalent amounts of antibody during transient transfection. Antibodies made in these lines completely lacked core fucosylation but had an otherwise normal glycosylation pattern. Cell lines stably expressing a model antibody were made from wild-type and ZFN-generated FUT8,/, cells. Clones from both lines had equivalent titer, specific productivity distributions, and integrated viable cell counts. Antibody titer in the best ZFN-generated FUT8,/, cell lines was fourfold higher than in the best-producing clones of FUT8,/, cells made by standard homologous recombination in a different CHO subtype. These data demonstrate the straightforward, ZFN-mediated transfer of the Fut8, phenotype to a production CHO cell line without adverse phenotypic effects. This process will speed the production of highly active, completely nonfucosylated therapeutic antibodies. Biotechnol. Bioeng. 2010;106: 774,783. © 2010 Wiley Periodicals, Inc. [source] Induction of apoptosis by A3 adenosine receptor agonist N6 -(3-iodobenzyl)-adenosine-5,- N -methylcarboxamide in human leukaemia cells: a possible involvement of intracellular mechanismACTA PHYSIOLOGICA, Issue 2 2010P. Mlejnek Abstract Aim:, The sensitivity of cancer cells which exhibit multi-drug resistance phenotype to A3 adenosine receptor (A3AR) agonist N6 -(3-iodobenzyl)-adenosine-5,- N -methylcarboxamide (IB-MECA) was studied. Methods:, To establish direct relationship between P-glycoprotein (P-gp, ABCB1 and MDR1) expression and IB-MECA induced cell death, a straightforward method for precise estimation of intracellular level of this A3AR agonist was developed. Results:, We subjected three human leukaemia cell lines HL-60, K562 and K562/HHT to treatment with micromolar concentrations of IB-MECA. Although all cell lines used expressed A3AR, there was a large difference in their sensitivity to IB-MECA. While HL-60 and K562 cells were almost equally sensitive, the K562/HHT cells, which exhibit a multi-drug resistance phenotype because of overexpression of P-gp, were significantly more resistant. We found that the intracellular level of IB-MECA in K562/HHT cells was approx. 10 times lower than those in HL-60 or K562 cells. Inhibitors of P-gp, including cyclosporine A (CsA) and verapamil (Vpa), increased the intracellular level of IB-MECA and reversed the resistance of K562/HHT cells to this drug. Accordingly, shRNA-mediated down-regulation of P-gp significantly increased the intracellular level of IB-MECA in K562/HHT cells which simultaneously exhibited reduced resistance to this A3AR agonist. In addition, an in vitro enzyme-based assay provided evidence that IB-MECA might serve as a substrate for P-gp. Conclusion:, Our results suggest that P-gp overexpression prevents cells from IB-MECA induced apoptosis despite the A3AR expression. Pro-apoptotic effect of IB-MECA seemed to strongly depend on its intracellular accumulation rather than on its interaction with A3AR. [source] Platinum(IV) Complexes of 3- and 4-Picolinic Acids Containing Ammine or Isopropylamine Ligands , Synthesis, Characterization, X-ray Structures, and Evaluation of Their Cytotoxic Activity against Cancer Cell Lines,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 30 2008María J. Macazaga Abstract The preparation and characterization of the new complexes trans -[PtCl4(NH3)(3-picolinic acid)] (1), trans -[PtCl4{NH2CH(CH3)2}(3-picolinic acid)] (2), trans -[PtCl4(NH3)(4-picolinic acid)] (3), and trans -[PtCl4{NH2CH(CH3)2}(4-picolinic acid)] (4) are described. The main structural feature of these complexes is the presence of ligands capable of multiple hydrogen-bonding interactions. Crystals of 1, 2, 3, and 4 suitable for single-crystal X-ray diffraction were grown, and the molecular structures of these compounds are discussed. In contrast to the inactive parent PtII complexes, the PtIV complexes displayed cytotoxic activity against various cancer cell lines used at the National Cancer Institute (NCI) for in vitro screens. Once more, the isopropylamine derivatives showed the best cytotoxicity values. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Improved In vitro Model Systems for Gastrointestinal Infection by Choice of Cell Line, pH, Microaerobic Conditions, and Optimization of Culture ConditionsHELICOBACTER, Issue 4 2007Sara K. Lindén Abstract Background:, Commonly used in vitro infection cultures do not mimic the human gastrointestinal tract with regard to pH and microaerobic conditions. Furthermore, despite the importance of mucin,Helicobacter interactions, the cell lines used have not been selected for appropriate mucin expression. To make in vitro studies more applicable to human disease, we have developed coculture methods taking these factors into account. Materials and methods:, Nine human gastrointestinal epithelial cell lines (MKN1, MKN7, MKN28, MKN45, KATO3, HFE145, PCAA/C11 Caco-2, and LS513) were investigated. Expression and glycosylation of mucins (MUC1, 2, 3, 4, 5AC, 5B, 6, 12, 13, and 16) were determined by immunohistochemistry. We analyzed the effect of microaerobic conditions and acidic pH on cell proliferation, viability, and apoptosis. Results:, Microaerobic culture, which is more physiological for the bacteria, did not adversely affect mammalian cell viability, proliferation, or induce apoptosis The cell lines varied in mucin expression, with MKN7 and MKN45 being most similar to gastric mucosa and Caco-2 and LS513 to intestinal mucosa, although none exactly matched normal mucosa. However, changes in culture conditions did not cause major changes in the mucin expression within cell lines. Conclusions:, Culture conditions mimicking the natural environment and allowing the bacterial cells to thrive had no effect on cell viability or apoptosis, and very little influence on mucin expression of human gastrointestinal cells. Thus, it is feasible, using the simple methods we present here, to substantially improve bacterial,mammalian cell in vitro coculture studies to make them more reflective of human infection. [source] X-linked QTL for knockdown resistance to high temperature in Drosophila melanogasterINSECT MOLECULAR BIOLOGY, Issue 4 2007F. M. Norry Abstract Knockdown Resistance to High Temperature (KRHT) is an adaptive trait of thermotolerance in insects. An interval mapping was performed on chromosome X of Drosophila melanogaster to search for quantitative trait loci (QTL) affecting KRHT. A backcross population was obtained from two lines that dramatically differ for KRHT. Microsatellites were used as markers. Composite interval mapping identified a large-effect QTL in the region of band 10 where putative candidate genes map. To further test for this QTL a set of recombinant (but non-inbred) lines was obtained from backcrosses between the parental lines used for the interval mapping. Recombinant line analysis confirmed that one QTL is targeted by band 10. We identify and discuss candidate loci contained within our QTL region. [source] Evaluating Tripsacum -introgressed maize germplasm after infestation with western corn rootworms (Coleoptera: Chrysomelidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2009D. A. Prischmann Abstract Maize (Zea mays L.) is a valuable commodity throughout the world, but corn rootworms (Chrysomelidae: Diabrotica spp.) often cause economic damage and increase production costs. Current rootworm management strategies have limitations, and in order to create viable management alternatives, researchers have been developing novel maize lines using Eastern gamagrass (Tripsacum dactyloides L.) germplasm, a wild relative of maize that is resistant to rootworms. Ten maize Tripsacum -introgressed inbred lines derived from recurrent selection of crosses with gamagrass and teosinte (Zea diploperennis Iltis) recombinants and two public inbred lines were assessed for susceptibility to western corn rootworm (Diabrotica virgifera virgifera LeConte) and yield in a two-year field study. Two experimental maize inbred lines, SDG11 and SDG20, had mean root damage ratings that were significantly lower than the susceptible public line B73. Two other experimental maize inbred lines, SDG12 and SDG6, appeared tolerant to rootworm damage because they exhibited yield increases after rootworm infestation in both years. In the majority of cases, mean yield per plant of experimental maize lines used in yield analyses was equal to or exceeded that of the public inbred lines B73 and W64A. Our study indicates that there is potential to use Tripsacum -introgressed maize germplasm in breeding programs to enhance plant resistance and/or tolerance to corn rootworms, although further research on insect resistance and agronomic potential of this germplasm needs to be conducted in F1 hybrids. [source] Aurora-A kinase phosphorylation of Aurora-A kinase interacting protein (AIP) and stabilization of the enzyme-substrate complexJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 5 2007Hiroshi Katayama Abstract Aurora-A is an oncogenic kinase that plays essential roles in mitosis as well as cell survival. Aurora-A interacting protein (AIP) was identified as a negative regulator of Aurora-A with its ectopic over expression inducing destabilization of Aurora-A protein. Here we present evidence that in human cells, contrary to the earlier report, AIP functions in stabilizing rather than destabilizing Aurora-A. Furthermore, AIP is phosphorylated on Serine 70 by Aurora-A but not Aurora-B and expression of phosphorylation mimic mutant of AIP results in prolonged protein stability compared to unphosphorylatable mutant. We observed that when co-expressed with AIP, protein levels of both Aurora-A and Aurora-B are markedly elevated regardless of their kinase activities and phosphorylation state of AIP. Interaction of Aurora kinases with AIP is necessary for this elevated stability. This phenomenon is commonly detected in several human cancer cell lines used in this study. Depletion of AIP by RNA interference decreased Aurora-A but not Aurora-B in two of the three cell lines analyzed, indicating that under physiological condition, AIP functions in stabilization of Aurora-A but not Aurora-B, though this regulation may be dependent on additional factors as well. Further, AIP siRNA induced cell cycle arrest at G2/M, which is consistent with anticipated loss of function of Aurora-A in these cells. Thus, our study provides the first evidence of a role for AIP in G2/M cell cycle progression by cooperatively regulating protein stabilization of its up-stream regulator, Aurora-A kinase through protein,protein interaction as well as protein phosphorylation. J. Cell. Biochem. 102: 1318,1331, 2007. © 2007 Wiley-Liss, Inc. [source] Low level of gene flow from cultivated beets (Beta vulgaris L. ssp. vulgaris) into Danish populations of sea beet (Beta vulgaris L. ssp. maritima (L.) Arcangeli)MOLECULAR ECOLOGY, Issue 5 2005N. S. ANDERSEN Abstract Gene flow from sugar beets to sea beets occurs in the seed propagation areas in southern Europe. Some seed propagation also takes place in Denmark, but here the crop,wild gene flow has not been investigated. Hence, we studied gene flow to sea beet populations from sugar beet lines used in Danish seed propagation areas. A set of 12 Danish, two Swedish, one French, one Italian, one Dutch, and one Irish populations of sea beets, and four lines of sugar beet were analysed. To evaluate the genetic variation and gene flow, eight microsatellite loci were screened. This analysis revealed hybridization with cultivated beet in one of the sea beet populations from the centre of the Danish seed propagation area. Triploid hybrids found in this population were verified with flow cytometry. Possible hybrids or introgressed plants were also found in the French and Italian populations. However, individual assignment test using a Bayesian method provided 100% assignment success of diploid individuals into their correct subspecies of origin, and a Bayesian Markov chain Monte Carlo (MC MC) approach revealed clear distinction of individuals into groups according to their subspecies of origin, with a zero level of genetic admixture among subspecies. This underlines that introgression beyond the first hybridization is not extensive. The overall pattern of genetic distance and structure showed that Danish and Swedish sea beet populations were closely related to each other, and they are both more closely related to the population from Ireland than to the populations from France, the Netherlands, and Italy. [source] Phytochemicals in olive-leaf extracts and their antiproliferative activity against cancer and endothelial cellsMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 5 2009Vlassios Goulas Abstract Olive oil compounds is a dynamic research area because Mediterranean diet has been shown to protect against cardiovascular disease and cancer. Olive leaves, an easily available natural material of low cost, share possibly a similar wealth of health benefiting bioactive phytochemicals. In this work, we investigated the antioxidant potency and antiproliferative activity against cancer and endothelial cells of water and methanol olive leaves extracts and analyzed their content in phytochemicals using LC-MS and LC-UV-SPE-NMR hyphenated techniques. Olive-leaf crude extracts were found to inhibit cell proliferation of human breast adenocarcinoma (MCF-7), human urinary bladder carcinoma (T-24) and bovine brain capillary endothelial (BBCE). The dominant compound of the extracts was oleuropein; phenols and flavonoids were also identified. These phytochemicals demonstrated strong antioxidant potency and inhibited cancer and endothelial cell proliferation at low micromolar concentrations, which is significant considering their high abundance in fruits and vegetables. The antiproliferative activity of crude extracts and phytochemicals against the cell lines used in this study is demonstrated for the first time. [source] Effects of climacostol on normal and tumoral mammalian cell linesTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 2 2005FEDERICO BUONANNO Climacostol, 1,3-dihydroxy-5-[(Z)-2,-nonenyl]benzene, is a natural toxin contained in the extrusomal cortical granules of the heterotrich ciliate Climacostomum virens. It is used for chemical defence against predators such as the raptorial ciliate Dileptus margaritifer and its cytotoxic activity has been assessed on several species of ciliates such as Didinium nasutum, Paramecium caudatum, and Blepharisma japonicum (Miyake et al. 2003, Europ. J. Protistol., 39:25,36). On the basis of its chemical structure, climacostol may be classified into the large group of natural compounds known as resorcinolic lipids, that show antimicrobial, antiparasitic, and antitumoral activities (Kozubek et al. 2003, Cell Moll. Biol. Lett., 6:351,355). To explore the possibility to use climacostol in medical applications, we examined the effects of chemically synthesized climacostol (Masaki et al. 2004, Tetrahedron, 60:7041,7048) on the growth and proliferation of tumoral and normal mammalian cell lines: (1) human promyelocytic leukaemia cells, HL60; (2) human squamous carcinoma cells, A431; and (3) non-tumoral cells derived from mice Leydig cells, TM3. It was observed that (1) a concentration of 10 ,g/ml of climacostol exerts a strong cytotoxic activity on all cell lines used; (2) at lower concentrations of 10 ng/ml and 1 ng/ml, the effect of climacostol is limited to the inhibition of the cell growth; and (3) the normal TM3 cells are more resistant to climacostol than the two tumoral HL60 and A431cell lines. The dose-dependent cytotoxic effects of climacostol encourage further investigation on the potential use of this ciliate toxin as an anti-cancer chemical. [source] 1,3-Diaryl-2-propenones and 2-Benzylidene-1,3-indandiones: A Quest for Compounds Displaying Greater Toxicity to Neoplasms than Normal CellsARCHIV DER PHARMAZIE, Issue 9 2010Hari N. Pati Abstract A series of 1,3-diaryl-2-propenones 2a,j and analogous 2-benzylidene-1,3-indandiones 3a,j were evaluated against various neoplasms and normal cells. In general, greater cytotoxic potencies and selective toxicity to human malignant cells were observed by the compounds in series 2 rather than 3. In particular, 2i emerged as a lead molecule having an average CC50 figure of 8.6,µM and a selective index value of 18. Various physicochemical features of 2a,j were correlated with the cytotoxic potencies to neoplastic cell lines which provide guidelines for expansion of this series of compounds. The enone 2i induced internucleosomal DNA fragmentation and activated caspase-3 in HL-60 cells suggesting that one of the ways in which the cytotoxicity of the compounds in series 2 is mediated towards some of the cell lines used in this study is by apoptosis. Neurotoxicity in mice was generally lower in series 2 than 3a,j. [source] Virus susceptibility of Chinese hamster ovary (CHO) cells and detection of viral contaminations by adventitious agent testingBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2010Andreas Berting Abstract Biopharmaceuticals are of increasing importance in the treatment of a variety of diseases. A remaining concern associated with their production is the potential introduction of adventitious agents into their manufacturing process, which may compromise the pathogen safety of a product and potentially cause stock-out situations for important medical supplies. To ensure the safety of biological therapeutics, regulatory guidance requires adventitious agent testing (AAT) of the bulk harvest. AAT is a deliberately promiscuous assay procedure which has been developed to indicate, ideally, the presence of any viral contaminant. One of the most important cell lines used in the production of biopharmaceuticals is Chinese hamster ovary (CHO) cells and while viral infections of CHO cells have occurred, a systematic screen of their virus susceptibility has never been published. We investigated the susceptibility of CHO cells to infection by 14 different viruses, including members of 12 families and representatives or the very species that were implicated in previously reported production cell infections. Based on our results, four different infection outcomes were distinguished, based on the possible combinations of the two factors (i) the induction, or not, of a cytopathic effect and (ii) the ability, or not, to replicate in CHO cells. Our results demonstrate that the current AAT is effective for the detection of viruses which are able to replicate in CHO cells. Due to the restricted virus susceptibility of CHO cells and the routine AAT of bulk harvests, our results provide re-assurance for the very high safety margins of CHO cell-derived biopharmaceuticals. Biotechnol. Bioeng. 2010;106: 598,607. © 2010 Wiley Periodicals, Inc. [source] | ||||||||||||||||