Latest Publications

@article{kabatkova_inhibition_2015,

title = {Inhibition of β-catenin signalling promotes DNA damage elicited by benzo[a]pyrene in a model of human colon cancer cells via CYP1 deregulation.},

author = {Markéta Kabátková and Ondřej Zapletal and Zuzana Tylichová and Jiří Neča and Miroslav Machala and Alena Milcová and Jan Topinka and Alois Kozubík and Jan Vondráček},

doi = {10.1093/mutage/gev019},

issn = {1464-3804 0267-8357},

year  = {2015},

date = {2015-07-01},

journal = {Mutagenesis},

volume = {30},

number = {4},

pages = {565–576},

abstract = {Deregulation of Wnt/β-catenin signalling plays an important role in the pathogenesis of colorectal cancer. Interestingly, this pathway has been recently implicated in transcriptional control of cytochrome P450 (CYP) family 1 enzymes, which are responsible for bioactivation of a number of dietary carcinogens. In the present study, we investigated the impact of inhibition of Wnt/β-catenin pathway on metabolism and genotoxicity of benzo[a]pyrene (BaP), a highly mutagenic polycyclic aromatic hydrocarbon and an efficient ligand of the aryl hydrocarbon receptor, which is known as a primary regulator of CYP1 expression, in cellular models derived from colorectal tumours. We observed that a synthetic inhibitor of β-catenin, JW74, significantly increased formation of BaP-induced DNA adducts in both colorectal adenoma and carcinoma-derived cell lines. Using the short interfering RNA (siRNA) targeting β-catenin, we then found that β-catenin knockdown in HCT116 colon carcinoma cells significantly enhanced formation of covalent DNA adducts by BaP and histone H2AX phosphorylation, as detected by (32)P-postlabelling technique and immunocytochemistry, respectively, and it also induced expression of DNA damage response genes, such as CDKN1A or DDB2. The increased formation of DNA adducts formed by BaP upon β-catenin knockdown corresponded with enhanced production of major BaP metabolites, as well as with an increased expression/activity of CYP1 enzymes. Finally, using siRNA-mediated knockdown of CYP1A1, we confirmed that this enzyme plays a major role in formation of BaP-induced DNA adducts in HCT116 cells. Taken together, the present results indicated that the siRNA-mediated inhibition of β-catenin signalling, which is aberrantly activated in a majority of colorectal cancers, modulated genotoxicity of dietary carcinogen BaP in colon cell model in vitro, via a mechanism involving up-regulation of CYP1 expression and activity.},

note = {Place: England},

keywords = {*DNA Damage, Apoptosis, Aryl Hydrocarbon/genetics/metabolism, Benzo(a)pyrene/*adverse effects, beta Catenin/*antagonists & inhibitors/genetics/metabolism, Blotting, Carcinogens, Cell Proliferation, Colonic Neoplasms/drug therapy/*etiology/*pathology, Cultured, Cytochrome P-450 CYP1A1/antagonists & inhibitors/genetics/*metabolism, DNA Adducts/*adverse effects, Environmental/adverse effects, Enzymologic/*drug effects, Gene Expression Regulation, Humans, Immunoenzyme Techniques, Messenger/genetics, Neoplastic/*drug effects, Real-Time Polymerase Chain Reaction, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA, Small Interfering/genetics, Tumor Cells, Western},

pubstate = {published},

tppubtype = {article}

}

@article{smerdova_inflammatory_2013,

title = {Inflammatory mediators accelerate metabolism of benzo[a]pyrene in rat alveolar type II cells: the role of enhanced cytochrome P450 1B1 expression.},

author = {Lenka Smerdová and Jiří Neča and Jana Svobodová and Jan Topinka and Jana Schmuczerová and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.1016/j.tox.2013.09.001},

issn = {1879-3185 0300-483X},

year  = {2013},

date = {2013-12-01},

journal = {Toxicology},

volume = {314},

number = {1},

pages = {30–38},

abstract = {Long-term deregulated inflammation represents one of the key factors contributing to lung cancer etiology. Previously, we have observed that tumor necrosis factor-α (TNF-α), a major pro-inflammatory cytokine, enhances genotoxicity of benzo[a]pyrene (B[a]P), a highly carcinogenic polycyclic aromatic hydrocarbon, in rat lung epithelial RLE-6TN cells, a model of alveolar type II cells. Therefore, we analyzed B[a]P metabolism in RLE-6TN cells under inflammatory conditions, simulated using either recombinant TNF-α, or a mixture of inflammatory mediators derived from activated alveolar macrophage cell line. Inflammatory conditions significantly accelerated BaP metabolism, as evidenced by decreased levels of both parent B[a]P and its metabolites. TNF-α altered production of the metabolites associated with dihydrodiol-epoxide and radical cation pathways of B[a]P metabolism, especially B[a]P-dihydrodiols, and B[a]P-diones. We then evaluated the role of cytochrome P450 1B1 (CYP1B1), which is strongly up-regulated in cells treated with B[a]P under inflammatory conditions, in the observed effects. The siRNA-mediated CYP1B1 knock-down increased levels of B[a]P and reduced formation of stable DNA adducts, thus confirming the essential role of CYP1B1 in B[a]P metabolism under inflammatory conditions. TNF-α also reduced expression of aldo-keto reductase 1C14, which may compete with CYP1B1 for B[a]P-7,8-dihydrodiol and divert it from the formation of ultimate B[a]P dihydrodiol epoxide. Together, the present data suggests that the CYP1B1-catalyzed metabolism of polycyclic aromatic hydrocarbons might contribute to their enhanced bioactivation and genotoxic effects under inflammatory conditions.},

note = {Place: Ireland},

keywords = {Animals, Aryl Hydrocarbon Hydroxylases/*biosynthesis/genetics, ATP Binding Cassette Transporter, Benzo(a)pyrene/*metabolism, Blotting, Cell Line, Conditioned, Culture Media, CYP1B1, Cytochrome P-450 CYP1B1, Cytokines/metabolism, DNA adducts, Inflammation, Inflammation Mediators/*pharmacology, metabolism, Oxidoreductases Acting on Aldehyde or Oxo Group Donors/biosynthesis/genetics, Polycyclic aromatic hydrocarbons, Pulmonary Alveoli/cytology/drug effects/*metabolism, Rats, Real-Time Polymerase Chain Reaction, RNA, Small Interfering, Subfamily B/biosynthesis/genetics, Tandem Mass Spectrometry, Transfection, Western},

pubstate = {published},

tppubtype = {article}

}

@article{gabelova_genotoxicity_2011,

title = {Genotoxicity of 7H-dibenzo[c,g]carbazole and its tissue-specific derivatives in human hepatoma HepG2 cells is related to CYP1A1/1A2 expression.},

author = {Alena Gábelová and Zuzana Valovičová and Monika Mesárošová and Lenka Trilecová and Eva Hrubá and Soňa Marvanová and Pavel Krčmár and Alena Milcová and Jana Schmuczerová and Jan Vondráček and Miroslav Machala and Jan Topinka},

doi = {10.1002/em.20664},

issn = {1098-2280 0893-6692},

year  = {2011},

date = {2011-10-01},

journal = {Environmental and molecular mutagenesis},

volume = {52},

number = {8},

pages = {636–645},

abstract = {The goal of this study was to investigate the genotoxicity of 7H-dibenzo[c,g]carbazole (DBC), a ubiquitous environmental pollutant, and its methyl derivatives, 5,9-dimethylDBC (DiMeDBC), a strict hepatocarcinogen, and N-methylDBC (N-MeDBC), a specific sarcomagen in human hepatoma HepG2 cells, and to infer potential mechanisms underlying the biological activity of particular carcinogen. All dibenzocarbazoles, regardless the tissue specificity, induced significant DNA strand break levels and micronuclei in HepG2 cells; though a mitotic spindle dysfunction rather than a chromosome breakage was implicated in N-MeDBC-mediated micronucleus formation. While DBC and N-MeDBC produced stable DNA adducts followed with p53 protein phosphorylation at Ser-15, DiMeDBC failed. A significant increase in DNA strand breaks following incubation of exposed cells with a repair-specific endonuclease (Fpg protein) suggested that either oxidative DNA damage or unstable DNA-adducts might underlie DiMeDBC genotoxicity in human hepatoma cells. DiMeDBC and N-MeDBC increased substantially also the amount of CYP1A1/2 expression in HepG2 cells. Pretreatment of cells with substances affecting AhR-mediated CYP1A family of enzymes expression; however, diminished DiMeDBC and N-MeDBC genotoxicity. Our data clearly demonstrated differences in the mechanisms involved in the biological activity of DiMeDBC and N-MeDBC in human hepatoma cells; the genotoxicity of these DBC derivatives is closely related to CYP1A1/2 expression.},

note = {Place: United States},

keywords = {Base Sequence, Blotting, Carbazoles/*toxicity, Cell Survival/drug effects, Chromosome-Defective/chemically induced/statistics & numerical data, Comet assay, Cytochrome P-450 CYP1A1/*genetics, Cytochrome P-450 CYP1A2/*genetics, DNA adducts, DNA Breaks, Dose-Response Relationship, Drug, Hep G2 Cells, Histones/metabolism, Humans, Micronuclei, Micronucleus Tests, Mitotic Index, Molecular Sequence Data, Mutagens/*toxicity, Phosphorylation, Real-Time Polymerase Chain Reaction, Tumor Suppressor Protein p53/metabolism, Western},

pubstate = {published},

tppubtype = {article}

}

@article{pernicova_androgen_2011,

title = {Androgen depletion induces senescence in prostate cancer cells through down-regulation of Skp2.},

author = {Zuzana Pernicová and Eva Slabáková and Gvantsa Kharaishvili and Jan Bouchal and Milan Král and Zuzana Kunická and Miroslav Machala and Alois Kozubík and Karel Souček},

doi = {10.1593/neo.11182},

issn = {1476-5586 1522-8002},

year  = {2011},

date = {2011-06-01},

journal = {Neoplasia (New York, N.Y.)},

volume = {13},

number = {6},

pages = {526–536},

abstract = {Although the induction of senescence in cancer cells is a potent mechanism of tumor suppression, senescent cells remain metabolically active and may secrete a broad spectrum of factors that promote tumorigenicity in neighboring malignant cells. Here we show that androgen deprivation therapy (ADT), a widely used treatment for advanced prostate cancer, induces a senescence-associated secretory phenotype in prostate cancer epithelial cells, indicated by increases in senescence-associated β-galactosidase activity, heterochromatin protein 1β foci, and expression of cathepsin B and insulin-like growth factor binding protein 3. Interestingly, ADT also induced high levels of vimentin expression in prostate cancer cell lines in vitro and in human prostate tumors in vivo. The induction of the senescence-associated secretory phenotype by androgen depletion was mediated, at least in part, by down-regulation of S-phase kinase-associated protein 2, whereas the neuroendocrine differentiation of prostate cancer cells was under separate control. These data demonstrate a previously unrecognized link between inhibition of androgen receptor signaling, down-regulation of S-phase kinase-associated protein 2, and the appearance of secretory, tumor-promoting senescent cells in prostate tumors. We propose that ADT may contribute to the development of androgen-independent prostate cancer through modulation of the tissue microenvironment by senescent cells.},

note = {Place: United States},

keywords = {Androgen Antagonists/*pharmacology, Androgen/metabolism, beta-Galactosidase/metabolism, Blotting, Cathepsin B/metabolism, Cell Line, Cellular Senescence/*drug effects, Confocal, Down-Regulation/*drug effects, Flow Cytometry, Humans, Insulin-Like Growth Factor Binding Protein 3/metabolism, Male, Microscopy, Prostatic Neoplasms/genetics/metabolism/pathology, PTEN Phosphohydrolase/metabolism, Receptors, RNA Interference, S-Phase Kinase-Associated Proteins/genetics/*metabolism, Signal Transduction/drug effects, Tumor, Vimentin/metabolism, Western},

pubstate = {published},

tppubtype = {article}

}

@article{vondalova_blanarova_cisplatin_2011,

title = {Cisplatin and a potent platinum(IV) complex-mediated enhancement of TRAIL-induced cancer cells killing is associated with modulation of upstream events in the extrinsic apoptotic pathway.},

author = {Olga Vondálová Blanárová and Iva Jelínková and Arpád Szöor and Belma Skender and Karel Soucek and Viktor Horváth and Alena Vaculová and Ladislav Andera and Petr Sova and János Szöllosi and Jirina Hofmanová and György Vereb and Alois Kozubík},

doi = {10.1093/carcin/bgq220},

issn = {1460-2180 0143-3334},

year  = {2011},

date = {2011-01-01},

journal = {Carcinogenesis},

volume = {32},

number = {1},

pages = {42–51},

abstract = {TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) can selectively trigger apoptosis in various cancer cell types. However, many cancer cells are resistant to death receptor-mediated apoptosis. Combination therapy with platinum complexes may affect TRAIL-induced signaling via modulation of various steps in apoptotic pathways. Here, we show that cisplatin or a more potent platinum(IV) complex LA-12 used in 20-fold lower concentration enhanced killing effects of TRAIL in human colon and prostate cancer cell lines via stimulation of caspase activity and overall apoptosis. Both platinum complexes increased DR5 surface expression in colon cancer cells. Small interfering RNA-mediated DR5 silencing rescued cells from sensitizing effects of platinum drugs on TRAIL-induced caspase-8 activation and apoptosis, showing the functional importance of DR5 in the effects observed. In addition, both cisplatin and LA-12 triggered the relocalization of DR4 and DR5 receptors to lipid rafts and accelerated internalization of TRAIL, which may also affect TRAIL signaling. Collectively, modulations of the initial steps of the extrinsic apoptotic pathway at the level of DR5 and plasma membrane are important for sensitization of colon and prostate cancer cells to TRAIL-induced apoptosis mediated by LA-12 and cisplatin.},

note = {Place: England},

keywords = {Amantadine/*analogs & derivatives/pharmacology, Apoptosis/*drug effects/physiology, Blotting, Cell Line, Cell Separation, Cisplatin/*pharmacology, Confocal, Flow Cytometry, Fluorescent Antibody Technique, Humans, Microscopy, Neoplasms/*metabolism, Organoplatinum Compounds/*pharmacology, Protein Transport/drug effects, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA Interference, Signal Transduction/*drug effects/physiology, TNF-Related Apoptosis-Inducing Ligand/*metabolism, TNF-Related Apoptosis-Inducing Ligand/metabolism, Tumor, Western},

pubstate = {published},

tppubtype = {article}

}

@article{takacova_role_2009,

title = {Role of aryl hydrocarbon receptor in modulation of the expression of the hypoxia marker carbonic anhydrase IX.},

author = {Martina Takacova and Tereza Holotnakova and Jan Vondracek and Miroslav Machala and Katerina Pencikova and Katarina Gradin and Lorenz Poellinger and Jaromir Pastorek and Silvia Pastorekova and Juraj Kopacek},

doi = {10.1042/BJ20080952},

issn = {1470-8728 0264-6021},

year  = {2009},

date = {2009-04-01},

journal = {The Biochemical journal},

volume = {419},

number = {2},

pages = {419–425},

abstract = {Tumour-associated expression of CA IX (carbonic anhydrase IX) is to a major extent regulated by HIF-1 (hypoxia-inducible factor-1) which is important for transcriptional activation and consists of the oxygen-regulated subunit HIF-1alpha and the partner factor ARNT [AhR (aryl hydrocarbon receptor) nuclear translocator]. We have previously observed that HIF-1alpha competes with the AhR for interaction with ARNT under conditions when both conditionally regulated factors are activated. We have therefore investigated whether TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin)-induced activation of the AhR pathway might interfere with CA IX expression. The results from the present study suggest that TCDD treatment reduces hypoxic induction of both CA IX mRNA and protein expression. Moreover, the transcriptional activity of the CA9 promoter was significantly reduced by expression of CAAhR (constitutively active AhR), which activates transcription in a ligand-independent manner. Finally, we found that ARNT is critical for both hypoxic induction and the TCDD-mediated inhibition of CA9 expression.},

note = {Place: England},

keywords = {alpha Subunit, Animals, Antigens, Aryl Hydrocarbon/genetics/metabolism/*physiology, Binding Sites, Blotting, Carbonic Anhydrase IX, Carbonic Anhydrases/genetics/*metabolism, Cell Hypoxia/genetics/*physiology, Cell Line, Chromatin Immunoprecipitation, Genetic/genetics, Humans, Hypoxia-Inducible Factor 1, Mice, Neoplasm/genetics, Polychlorinated Dibenzodioxins/pharmacology, Polymerase Chain Reaction, Promoter Regions, Protein Binding/drug effects, Receptors, Reverse Transcriptase Polymerase Chain Reaction, Signal Transduction/drug effects, Tumor, Western},

pubstate = {published},

tppubtype = {article}

}

@article{gavelova_reduction_2008,

title = {Reduction of doxorubicin and oracin and induction of carbonyl reductase in human breast carcinoma MCF-7 cells.},

author = {Martina Gavelová and Jana Hladíková and Lenka Vildová and Romana Novotná and Jan Vondrácek and Pavel Krcmár and Miroslav Machala and Lenka Skálová},

doi = {10.1016/j.cbi.2008.07.011},

issn = {0009-2797},

year  = {2008},

date = {2008-10-01},

journal = {Chemico-biological interactions},

volume = {176},

number = {1},

pages = {9–18},

abstract = {In cancer cells, the drug-metabolizing enzymes may deactivate cytostatics, thus contributing to their survival. Moreover, the induction of these enzymes may also contribute to development of drug-resistance through acceleration of cytostatics deactivation. However, the principal metabolic pathways contributing to deactivation of many cytostatics still remain poorly defined. The main aims of the present study were: (i) to compare the reductive deactivation of cytostatic drugs doxorubicin (DOX) and oracin (ORC) in human breast cancer MCF-7 cells; (ii) to identify major enzyme(s) involved in the carbonyl reduction; and iii) to evaluate the activities and expression of selected carbonyl reducing enzymes in MCF-7 cells upon a short-term (48 h) exposure to either DOX or ORC. We found that MCF-7 cells were able to effectively metabolize both DOX and ORC through reduction of their carbonyl groups. The reduction of ORC was stereospecific, with a preferential formation of + enantiomer of dihydrooracin (DHO). The cytosolic carbonyl reductase CBR1 seemed to be a principal enzyme reducing both drugs, while cytosolic aldo-keto reductase AKR1C3 or microsomal reductases probably did not play important role in metabolism of either DOX or ORC. The exposure of MCF-7 cells to low (nanomolar) concentrations of DOX or ORC caused a significant elevation of reduction rates of both cytostatics, accompanied with an increase of CBR1 protein levels. Taken together, the present results seem to suggest that the accelerated metabolic deactivation of ORC or DOX might contribute to the survival of breast cancer cells during exposure to these cytostatics.},

note = {Place: Ireland},

keywords = {3-Hydroxysteroid Dehydrogenases/antagonists & inhibitors/genetics/metabolism, Alcohol Oxidoreductases/antagonists & inhibitors/*biosynthesis/genetics/metabolism, Aldehyde Reductase, Aldo-Keto Reductase Family 1 Member C3, Aldo-Keto Reductases, Biotransformation/drug effects, Blotting, Breast Neoplasms/*enzymology/genetics, Cell Line, Dose-Response Relationship, Doxorubicin/analogs & derivatives/chemistry/*metabolism/pharmacology, Drug, Enzyme Induction/drug effects, Enzyme Inhibitors/pharmacology, Ethanolamines/chemistry/*metabolism/pharmacology, Gene Expression Regulation, Humans, Hydroxyprostaglandin Dehydrogenases/antagonists & inhibitors/genetics/metabolism, Isoquinolines/chemistry/*metabolism/pharmacology, Kinetics, Messenger/genetics/metabolism, Methacrylates/pharmacology, Neoplastic/drug effects, Oxidation-Reduction/drug effects, Phenylpropionates/pharmacology, Quercetin/analogs & derivatives/pharmacology, RNA, Subcellular Fractions/drug effects/metabolism, Tumor, Western},

pubstate = {published},

tppubtype = {article}

}

@article{ondrouskova_alternative_2008,

title = {Alternative pathways of programmed cell death are activated in cells with defective caspase-dependent apoptosis.},

author = {Eva Ondrousková and Karel Soucek and Viktor Horváth and Jan Smarda},

doi = {10.1016/j.leukres.2007.05.012},

issn = {0145-2126},

year  = {2008},

date = {2008-04-01},

journal = {Leukemia research},

volume = {32},

number = {4},

pages = {599–609},

abstract = {Loss of programmed cell death pathways is one of the features of malignancy that complicate the response of cancer cells to a therapy. Activation of alternative cell death pathways offers a promising approach to enhance efficiency of cancer chemotherapy. We analysed programmed cell death pathways of v-myb-transformed BM2 monoblasts induced by arsenic trioxide, cycloheximide and camptothecin with U937 promonocytes as a reference cell line. We show that induced death of BM2 cells is not executed by caspases but rather by alternative cell death pathways. Camptothecin induces the lysosome-dependent cell death, arsenic trioxide induces autophagy, and most of cycloheximide-treated BM2 cells die by necrosis. The fact that alternative cell death pathways can be switched in cells with defects in activation and/or function of caspases suggests that understanding and targeting of these pathways could improve therapy of cancer cells suffering from defective apoptosis.},

note = {Place: England},

keywords = {Animals, Antineoplastic Agents/*pharmacology, Apoptosis/*drug effects, Arsenic Trioxide, Arsenicals/pharmacology, Autophagy/*drug effects, Blotting, Camptothecin/pharmacology, Caspases/*metabolism, Cell Line, Cell Transformation, Chickens, Cycloheximide/pharmacology, Fluorescence, Genes, Humans, Microscopy, myb/physiology, Necrosis, Neoplastic/*pathology, Oxides/pharmacology, Signal Transduction/*drug effects, Transformed, U937 Cells/drug effects, Western},

pubstate = {published},

tppubtype = {article}

}

@article{horvath_platinumiv_2006,

title = {Platinum(IV) complex with adamantylamine overcomes intrinsic resistance to cisplatin in ovarian cancer cells.},

author = {Viktor Horváth and Olga Blanárová and Lenka Svihálková-Sindlerová and Karel Soucek and Jirina Hofmanová and Petr Sova and Ales Kroutil and Peter Fedorocko and Alois Kozubík},

doi = {10.1016/j.ygyno.2005.11.016},

issn = {0090-8258},

year  = {2006},

date = {2006-07-01},

journal = {Gynecologic oncology},

volume = {102},

number = {1},

pages = {32–40},

abstract = {OBJECTIVES: The resistance of tumor cells to cisplatin remains a major cause of treatment failure in cancer patients. In this study, the ability of Pt(IV) complex with adamantylamine-LA-12 and its reduced counterpart with lower oxidation state Pt(II)-LA-9 to overcome intrinsic cisplatin resistance was investigated. METHODS: The ovarian adenocarcinoma SK-OV-3 cells were exposed to cisplatin, LA-9, or LA-12 for 72 h and the effects of drug concentrations that caused 10% or 50% inhibition of cell proliferation were determined. After 24-72 h of sustained exposure viability, apoptosis and inhibition of proliferation were analyzed. DNA synthesis and cell cycle analysis were performed simultaneously in order to determine the modulation of cell cycle after platinum complexes treatment. RESULTS: Lung Resistance-related Protein (LRP/MVP) was detected in SK-OV-3 cells but not in the other two ovarian cancer lines with different sensitivity to cisplatin. LRP/MVP overexpression may be an important factor contributing to intrinsic cisplatin resistance. Interestingly, Pt(IV) complex-LA-12 had approximately 2.7-fold lower IC(50) concentration than LA-9 or cisplatin in SK-OV-3 cells. Moreover, LA-12 caused persistent accumulation of cells in S-phase of the cell cycle while LA-9 and cisplatin treatment-induced S-phase arrest was transient and shifted to G(2)/M-phase at later intervals. Apoptosis seemed to be not the dominant type of cell death caused by such the derivatives, but it was the most intensive after LA-12 treatment. CONCLUSIONS: We found strong differences between effects of Pt(IV) complex-LA-12 and Pt(II) derivatives-LA-9 and cisplatin on cytokinetic parameters. Overall, LA-12 but not its reduced Pt(II) counterpart LA-9 is the compound effective in p53 null human ovarian cancer cells and it is able to overcome intrinsic cisplatin resistance in these cells.},

note = {Place: United States},

keywords = {Adenocarcinoma/*drug therapy/metabolism/pathology, Amantadine/administration & dosage/analogs & derivatives, Antineoplastic Combined Chemotherapy Protocols/*pharmacology, Blotting, Cell Cycle/drug effects, Cell Growth Processes/drug effects, Cell Line, Cisplatin/administration & dosage, DNA, Drug resistance, Female, Humans, Neoplasm, Neoplasm Proteins/biosynthesis, Neoplasm/biosynthesis, Organoplatinum Compounds/administration & dosage/*pharmacology, Ovarian Neoplasms/*drug therapy/metabolism/pathology, Poly(ADP-ribose) Polymerases/metabolism, Tumor, Vault Ribonucleoprotein Particles/biosynthesis, Western},

pubstate = {published},

tppubtype = {article}

}

@article{soucek_normal_2006,

title = {Normal and prostate cancer cells display distinct molecular profiles of alpha-tubulin posttranslational modifications.},

author = {Karel Soucek and Andrés Kamaid and Anh D. Phung and Lukás Kubala and J. Chloë Bulinski and Richart W. Harper and Jason P. Eiserich},

doi = {10.1002/pros.20416},

issn = {0270-4137},

year  = {2006},

date = {2006-06-01},

journal = {The Prostate},

volume = {66},

number = {9},

pages = {954–965},

abstract = {BACKGROUND: Multiple diverse posttranslational modifications of alpha-tubulin such as detyrosination, further cleavage of the penultimate glutamate residue (Delta2-tubulin), acetylation, and polyglutamylation increase the structural and functional diversity of microtubules. METHODS: Herein, we characterized the molecular profile of alpha-tubulin posttranslational modifications in normal human prostate epithelial cells (PrEC), immortalized normal prostate epithelial cells (PZ-HPV-7), androgen-dependent prostate cancer cells (LNCaP), transitional androgen-independent prostate cancer cells (LNCaP-cds and CWR22Rv1), and androgen-independent prostate cancer cells (PC3). RESULTS: Compared to PrEC and PZ-HPV-7 cells, all cancer cells exhibited elevated levels of detyrosinated and polyglutamylated alpha-tubulin, that was paralleled by decreased protein levels of tubulin tyrosine ligase (TTL). In contrast, PrEC and PZ-HPV-7 cells expressed markedly higher levels of Delta2-tubulin. Whereas alpha-tubulin acetylation levels were generally equivalent in all the cell lines, PC3 cells did not display detectable levels of Ac-tubulin. CONCLUSION: These data may reveal novel biomarkers of prostate cancer and new therapeutic targets.},

note = {Place: United States},

keywords = {*Protein Processing, Acetylation, Androgen/analysis, Androgens/physiology, Blotting, Cell Line, Disease Progression, Electrophoresis, Epithelium/chemistry/metabolism/pathology, Fluorescence, Humans, Male, Microscopy, Peptide Synthases/analysis/metabolism, Polyacrylamide Gel, Polyglutamic Acid/analysis, Post-Translational, Prostate/*chemistry/cytology/metabolism, Prostatic Neoplasms/*chemistry/metabolism/pathology, Receptors, Tubulin/*analysis/*metabolism, Tumor, Tyrosine/analysis, Western},

pubstate = {published},

tppubtype = {article}

}

@article{vaculova_ethanol_2004,

title = {Ethanol acts as a potent agent sensitizing colon cancer cells to the TRAIL-induced apoptosis.},

author = {Alena Vaculová and Jirina Hofmanová and Karel Soucek and Ladislav Andera and Alois Kozubík},

doi = {10.1016/j.febslet.2004.10.013},

issn = {0014-5793},

year  = {2004},

date = {2004-11-01},

journal = {FEBS letters},

volume = {577},

number = {1-2},

pages = {309–313},

abstract = {Identification of mechanisms of modulation of the TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis is important for its potential use in anticancer therapy. Ethanol can induce cell death in vitro and in vivo by different signalling pathways. Its effect in combination with death ligands is unknown. We investigated how ethanol modulates the effects of TRAIL in colon cancer cells. After combined TRAIL and ethanol treatment, a potentiation of caspase-8, -9, -3 activation, a proapoptotic Bid protein cleavage, a decrease of mitochondrial membrane potential, a complete poly(ADP)ribose polymerase cleavage, and disappearance of antiapoptotic Mcl-1 protein were demonstrated. Ethanol acts as a potent agent sensitizing colon cancer cells to TRAIL-induced apoptosis.},

note = {Place: England},

keywords = {Apoptosis Regulatory Proteins, Apoptosis/*drug effects/physiology, BH3 Interacting Domain Death Agonist Protein, Blotting, Carrier Proteins/metabolism, Caspases/metabolism, Colonic Neoplasms/enzymology/metabolism/*pathology, Ethanol/*pharmacology, HT29 Cells, Humans, Membrane Glycoproteins/*physiology, Myeloid Cell Leukemia Sequence 1 Protein, Neoplasm Proteins/metabolism, Proto-Oncogene Proteins c-bcl-2/metabolism, TNF-Related Apoptosis-Inducing Ligand, Tumor Necrosis Factor-alpha/*physiology, Western},

pubstate = {published},

tppubtype = {article}

}

@article{machala_inhibition_2003,

title = {Inhibition of gap junctional intercellular communication by noncoplanar polychlorinated biphenyls: inhibitory potencies and screening for potential mode(s) of action.},

author = {Miroslav Machala and Ludek Bláha and Jan Vondrácek and James E. Trosko and Jacob Scott and Brad L. Upham},

doi = {10.1093/toxsci/kfg209},

issn = {1096-6080 1096-0929},

year  = {2003},

date = {2003-11-01},

journal = {Toxicological sciences : an official journal of the Society of Toxicology},

volume = {76},

number = {1},

pages = {102–111},

abstract = {Polychlorinated biphenyls (PCBs), a structurally diverse group of environmental pollutants, are effective promoters in two-stage cancer models, which implies that epigenetic mechanisms are involved. Inhibition of gap junctional intercellular communication (GJIC) belongs among critical epigenetic events of tumor promotion. We determined the relative potencies of a series of environmentally relevant PCB congeners to inhibit GJIC in vitro in a rat liver epithelial cell line with pluripotent oval cell characteristics. The nonplanar PCBs were potent inhibitors of GJIC, whereas the coplanar PCBs did not inhibit GJIC. We then compared the effects of the coplanar PCB 126 (3,3',4,4',5-pentachlorobiphenyl) and the noncoplanar PCB 153 (2,2',4,4',5,5'-hexachlorobiphenyl) with effects of two model GJIC inhibitors, a tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) and epidermal growth factor (EGF). In contrast to TPA or EGF, PCB 153 elicited a long-term downregulation of GJIC (up to 48 h). Using Western blot analysis with phospho-specific antibodies, it was found that PCB 153, and not PCB 126, activated mitogen-activated protein kinases ERK1/2; however in contrast to TPA and EGF, this activation was observed at the time points subsequent to GJIC inhibition. Moreover, blocking of ERK1/2 activation did not prevent the GJIC inhibition induced by PCB 153. Therefore, additional intracellular signaling pathways potentially involved in the downregulation of GJIC by PCBs were screened by using specific chemical probes inhibiting serine/threonine kinases, tyrosine kinases, and phospholipases. The inhibition of diacylglycerol lipase partially blocked and the selective inhibition of Src kinases and phosphatidylcholine-specific phospholipase C (PC-PLC) completely blocked the inhibitory effects of the noncoplanar PCB on GJIC, indicating that PC-PLC or sphingomyelinase and Src might be upstream regulators of noncoplanar PCB-induced inhibition of GJIC.},

note = {Place: United States},

keywords = {Animals, Blotting, Cell Line, Epidermal Growth Factor/toxicity, Epithelial Cells/drug effects/enzymology, Gap Junctions/*drug effects/enzymology, Liver/cytology, Mitogen-Activated Protein Kinases/metabolism, Polychlorinated Biphenyls/*toxicity, Rats, Signal Transduction/*drug effects, Sphingomyelin Phosphodiesterase/metabolism, src-Family Kinases/metabolism, Tetradecanoylphorbol Acetate/toxicity, Western},

pubstate = {published},

tppubtype = {article}

}