2021
Němec, Václav; Maier, Lukáš; Berger, Benedict-Tilman; Chaikuad, Apirat; Drápela, Stanislav; Souček, Karel; Knapp, Stefan; Paruch, Kamil
Highly selective inhibitors of protein kinases CLK and HIPK with the furo[3,2-b]pyridine core. Journal Article
In: European journal of medicinal chemistry, vol. 215, pp. 113299, 2021, ISSN: 1768-3254 0223-5234, (Place: France).
Abstract | Links | BibTeX | Tags: 2-b]pyridine, Animals, Carrier Proteins/*antagonists & inhibitors/metabolism, CLK, Crystallography, Furans/chemical synthesis/metabolism/*pharmacology, Furo[3, HIPK, Humans, Inhibitor, Kinase, MCF-7 Cells, Mice, Molecular Structure, MU1210, MU135, MU1787, Protein Binding, Protein Kinase Inhibitors/chemical synthesis/metabolism/*pharmacology, Protein Serine-Threonine Kinases/*antagonists & inhibitors/metabolism, Pyridines/chemical synthesis/metabolism/*pharmacology, Structure-Activity Relationship, X-Ray
@article{nemec_highly_2021,
title = {Highly selective inhibitors of protein kinases CLK and HIPK with the furo[3,2-b]pyridine core.},
author = {Václav Němec and Lukáš Maier and Benedict-Tilman Berger and Apirat Chaikuad and Stanislav Drápela and Karel Souček and Stefan Knapp and Kamil Paruch},
doi = {10.1016/j.ejmech.2021.113299},
issn = {1768-3254 0223-5234},
year = {2021},
date = {2021-04-01},
journal = {European journal of medicinal chemistry},
volume = {215},
pages = {113299},
abstract = {The furo [3,2-b]pyridine motif represents a relatively underexplored central pharmacophore in the area of kinase inhibitors. Herein, we report flexible synthesis of 3,5-disubstituted furo [3,2-b]pyridines that relies on chemoselective couplings of newly prepared 5-chloro-3-iodofuro [3,2-b]pyridine. This methodology allowed efficient second-generation synthesis of the state-of-the-art chemical biology probe for CLK1/2/4 MU1210, and identification of the highly selective inhibitors of HIPKs MU135 and MU1787 which are presented and characterized in this study, including the X-ray crystal structure of MU135 in HIPK2. chemical biology probe.},
note = {Place: France},
keywords = {2-b]pyridine, Animals, Carrier Proteins/*antagonists & inhibitors/metabolism, CLK, Crystallography, Furans/chemical synthesis/metabolism/*pharmacology, Furo[3, HIPK, Humans, Inhibitor, Kinase, MCF-7 Cells, Mice, Molecular Structure, MU1210, MU135, MU1787, Protein Binding, Protein Kinase Inhibitors/chemical synthesis/metabolism/*pharmacology, Protein Serine-Threonine Kinases/*antagonists & inhibitors/metabolism, Pyridines/chemical synthesis/metabolism/*pharmacology, Structure-Activity Relationship, X-Ray},
pubstate = {published},
tppubtype = {article}
}
2020
Kauerová, Tereza; Goněc, Tomáš; Jampílek, Josef; Hafner, Susanne; Gaiser, Ann-Kathrin; Syrovets, Tatiana; Fedr, Radek; Souček, Karel; Kollar, Peter
Ring-Substituted 1-Hydroxynaphthalene-2-Carboxanilides Inhibit Proliferation and Trigger Mitochondria-Mediated Apoptosis. Journal Article
In: International journal of molecular sciences, vol. 21, no. 10, 2020, ISSN: 1422-0067, (Place: Switzerland).
Abstract | Links | BibTeX | Tags: Anilides/chemistry/*pharmacology, Antineoplastic Agents/chemistry/pharmacology, antiproliferative effect, Apoptosis, Apoptosis/*drug effects, Cell Cycle, Cell Cycle/drug effects, Cell Proliferation/*drug effects, Cell Survival/drug effects, Humans, hydroxynaphthalene carboxamides, MCF-7 Cells, Membrane Potential, Mitochondria/*drug effects/metabolism, Mitochondrial/drug effects, Molecular Structure, Naphthols/*chemistry, Reactive Oxygen Species/metabolism, salicylanilides, Salicylanilides/chemistry/pharmacology, Structure-Activity Relationship, Superoxides/metabolism, THP-1 Cells
@article{kauerova_ring-substituted_2020,
title = {Ring-Substituted 1-Hydroxynaphthalene-2-Carboxanilides Inhibit Proliferation and Trigger Mitochondria-Mediated Apoptosis.},
author = {Tereza Kauerová and Tomáš Goněc and Josef Jampílek and Susanne Hafner and Ann-Kathrin Gaiser and Tatiana Syrovets and Radek Fedr and Karel Souček and Peter Kollar},
doi = {10.3390/ijms21103416},
issn = {1422-0067},
year = {2020},
date = {2020-05-01},
journal = {International journal of molecular sciences},
volume = {21},
number = {10},
abstract = {Ring-substituted 1-hydroxynaphthalene-2-carboxanilides were previously investigated for their antimycobacterial properties. In our study, we have shown their antiproliferative and cell death-inducing effects in cancer cell lines. Cell proliferation and viability were assessed by WST-1 assay and a dye exclusion test, respectively. Cell cycle distribution, phosphatidylserine externalization, levels of reactive oxygen or nitrogen species (RONS), mitochondrial membrane depolarization, and release of cytochrome c were estimated by flow cytometry. Levels of regulatory proteins were determined by Western blotting. Our data suggest that the ability to inhibit the proliferation of THP-1 or MCF-7 cells might be referred to meta- or para-substituted derivatives with electron-withdrawing groups -F, -Br, or -CF(3) at anilide moiety. This effect was accompanied by accumulation of cells in G1 phase. Compound 10 also induced apoptosis in THP-1 cells in association with a loss of mitochondrial membrane potential and production of mitochondrial superoxide. Our study provides a new insight into the action of salicylanilide derivatives, hydroxynaphthalene carboxamides, in cancer cells. Thus, their structure merits further investigation as a model moiety of new small-molecule compounds with potential anticancer properties.},
note = {Place: Switzerland},
keywords = {Anilides/chemistry/*pharmacology, Antineoplastic Agents/chemistry/pharmacology, antiproliferative effect, Apoptosis, Apoptosis/*drug effects, Cell Cycle, Cell Cycle/drug effects, Cell Proliferation/*drug effects, Cell Survival/drug effects, Humans, hydroxynaphthalene carboxamides, MCF-7 Cells, Membrane Potential, Mitochondria/*drug effects/metabolism, Mitochondrial/drug effects, Molecular Structure, Naphthols/*chemistry, Reactive Oxygen Species/metabolism, salicylanilides, Salicylanilides/chemistry/pharmacology, Structure-Activity Relationship, Superoxides/metabolism, THP-1 Cells},
pubstate = {published},
tppubtype = {article}
}
2019
Němec, Václav; Hylsová, Michaela; Maier, Lukáš; Flegel, Jana; Sievers, Sonja; Ziegler, Slava; Schröder, Martin; Berger, Benedict-Tilman; Chaikuad, Apirat; Valčíková, Barbora; Uldrijan, Stjepan; Drápela, Stanislav; Souček, Karel; Waldmann, Herbert; Knapp, Stefan; Paruch, Kamil
Furo[3,2-b]pyridine: A Privileged Scaffold for Highly Selective Kinase Inhibitors and Effective Modulators of the Hedgehog Pathway. Journal Article
In: Angewandte Chemie (International ed. in English), vol. 58, no. 4, pp. 1062–1066, 2019, ISSN: 1521-3773 1433-7851, (Place: Germany).
Abstract | Links | BibTeX | Tags: Binding Sites, biological activity, Cell Survival/drug effects, chemical probes, Furans/*chemistry, Hedgehog Proteins/*chemistry, heterocycles, Humans, inhibitors, Inhibitory Concentration 50, kinases, MCF-7 Cells, Molecular Structure, Protein Binding, Protein Kinase Inhibitors/*chemical synthesis/chemistry/pharmacology, Pyridines/*chemistry, Small Molecule Libraries/*chemical synthesis/chemistry/pharmacology
@article{nemec_furo32-bpyridine_2019,
title = {Furo[3,2-b]pyridine: A Privileged Scaffold for Highly Selective Kinase Inhibitors and Effective Modulators of the Hedgehog Pathway.},
author = {Václav Němec and Michaela Hylsová and Lukáš Maier and Jana Flegel and Sonja Sievers and Slava Ziegler and Martin Schröder and Benedict-Tilman Berger and Apirat Chaikuad and Barbora Valčíková and Stjepan Uldrijan and Stanislav Drápela and Karel Souček and Herbert Waldmann and Stefan Knapp and Kamil Paruch},
doi = {10.1002/anie.201810312},
issn = {1521-3773 1433-7851},
year = {2019},
date = {2019-01-01},
journal = {Angewandte Chemie (International ed. in English)},
volume = {58},
number = {4},
pages = {1062–1066},
abstract = {Reported is the identification of the furo[3,2-b]pyridine core as a novel scaffold for potent and highly selective inhibitors of cdc-like kinases (CLKs) and efficient modulators of the Hedgehog signaling pathway. Initially, a diverse target compound set was prepared by synthetic sequences based on chemoselective metal-mediated couplings, including assembly of the furo[3,2-b]pyridine scaffold by copper-mediated oxidative cyclization. Optimization of the subseries containing 3,5-disubstituted furo[3,2-b]pyridines afforded potent, cell-active, and highly selective inhibitors of CLKs. Profiling of the kinase-inactive subset of 3,5,7-trisubstituted furo[3,2-b]pyridines revealed sub-micromolar modulators of the Hedgehog pathway.},
note = {Place: Germany},
keywords = {Binding Sites, biological activity, Cell Survival/drug effects, chemical probes, Furans/*chemistry, Hedgehog Proteins/*chemistry, heterocycles, Humans, inhibitors, Inhibitory Concentration 50, kinases, MCF-7 Cells, Molecular Structure, Protein Binding, Protein Kinase Inhibitors/*chemical synthesis/chemistry/pharmacology, Pyridines/*chemistry, Small Molecule Libraries/*chemical synthesis/chemistry/pharmacology},
pubstate = {published},
tppubtype = {article}
}
2017
Samadder, Pounami; Suchánková, Tereza; Hylse, Ondřej; Khirsariya, Prashant; Nikulenkov, Fedor; Drápela, Stanislav; Straková, Nicol; Vaňhara, Petr; Vašíčková, Kateřina; Kolářová, Hana; Binó, Lucia; Bittová, Miroslava; Ovesná, Petra; Kollár, Peter; Fedr, Radek; Ešner, Milan; Jaroš, Josef; Hampl, Aleš; Krejčí, Lumír; Paruch, Kamil; Souček, Karel
In: Molecular cancer therapeutics, vol. 16, no. 9, pp. 1831–1842, 2017, ISSN: 1538-8514 1535-7163, (Place: United States).
Abstract | Links | BibTeX | Tags: Animal, Animals, Antineoplastic Agents/*chemical synthesis/*pharmacology, Apoptosis/drug effects, Biomarkers, Cell Cycle Checkpoints/drug effects, Cell Cycle/drug effects, Cell Line, Checkpoint Kinase 1/*antagonists & inhibitors, Dealkylation/drug effects, Disease Models, Dose-Response Relationship, Drug, Drug resistance, Humans, Methylation, Mice, Molecular Structure, Neoplasm/*drug effects, Protein Kinase Inhibitors/*chemical synthesis/*pharmacology, Pyrazoles/pharmacology, Pyrimidines/pharmacology, Tumor, Xenograft Model Antitumor Assays
@article{samadder_synthesis_2017,
title = {Synthesis and Profiling of a Novel Potent Selective Inhibitor of CHK1 Kinase Possessing Unusual N-trifluoromethylpyrazole Pharmacophore Resistant to Metabolic N-dealkylation.},
author = {Pounami Samadder and Tereza Suchánková and Ondřej Hylse and Prashant Khirsariya and Fedor Nikulenkov and Stanislav Drápela and Nicol Straková and Petr Vaňhara and Kateřina Vašíčková and Hana Kolářová and Lucia Binó and Miroslava Bittová and Petra Ovesná and Peter Kollár and Radek Fedr and Milan Ešner and Josef Jaroš and Aleš Hampl and Lumír Krejčí and Kamil Paruch and Karel Souček},
doi = {10.1158/1535-7163.MCT-17-0018},
issn = {1538-8514 1535-7163},
year = {2017},
date = {2017-09-01},
journal = {Molecular cancer therapeutics},
volume = {16},
number = {9},
pages = {1831–1842},
abstract = {Checkpoint-mediated dependency of tumor cells can be deployed to selectively kill them without substantial toxicity to normal cells. Specifically, loss of CHK1, a serine threonine kinase involved in the surveillance of the G(2)-M checkpoint in the presence of replication stress inflicted by DNA-damaging drugs, has been reported to dramatically influence the viability of tumor cells. CHK1's pivotal role in maintaining genomic stability offers attractive opportunity for increasing the selectivity, effectivity, and reduced toxicity of chemotherapy. Some recently identified CHK1 inhibitors entered clinical trials in combination with DNA antimetabolites. Herein, we report synthesis and profiling of MU380, a nontrivial analogue of clinically profiled compound SCH900776 possessing the highly unusual N-trifluoromethylpyrazole motif, which was envisioned not to undergo metabolic oxidative dealkylation and thereby provide greater robustness to the compound. MU380 is a selective and potent inhibitor of CHK1 which sensitizes a variety of tumor cell lines to hydroxyurea or gemcitabine up to 10 times. MU380 shows extended inhibitory effects in cells, and unlike SCH900776, does not undergo in vivo N-dealkylation to the significantly less selective metabolite. Compared with SCH900776, MU380 in combination with GEM causes higher accumulation of DNA damage in tumor cells and subsequent enhanced cell death, and is more efficacious in the A2780 xenograft mouse model. Overall, MU380 represents a novel state-of-the-art CHK1 inhibitor with high potency, selectivity, and improved metabolic robustness to oxidative N-dealkylation. Mol Cancer Ther; 16(9); 1831-42. ©2017 AACR.},
note = {Place: United States},
keywords = {Animal, Animals, Antineoplastic Agents/*chemical synthesis/*pharmacology, Apoptosis/drug effects, Biomarkers, Cell Cycle Checkpoints/drug effects, Cell Cycle/drug effects, Cell Line, Checkpoint Kinase 1/*antagonists & inhibitors, Dealkylation/drug effects, Disease Models, Dose-Response Relationship, Drug, Drug resistance, Humans, Methylation, Mice, Molecular Structure, Neoplasm/*drug effects, Protein Kinase Inhibitors/*chemical synthesis/*pharmacology, Pyrazoles/pharmacology, Pyrimidines/pharmacology, Tumor, Xenograft Model Antitumor Assays},
pubstate = {published},
tppubtype = {article}
}
Maier, Lukáš; Khirsariya, Prashant; Hylse, Ondřej; Adla, Santosh Kumar; Černová, Lenka; Poljak, Michal; Krajčovičová, Soňa; Weis, Erik; Drápela, Stanislav; Souček, Karel; Paruch, Kamil
Diastereoselective Flexible Synthesis of Carbocyclic C-Nucleosides. Journal Article
In: The Journal of organic chemistry, vol. 82, no. 7, pp. 3382–3402, 2017, ISSN: 1520-6904 0022-3263, (Place: United States).
Abstract | Links | BibTeX | Tags: Cell Proliferation/drug effects, Cells, Cultured, Cyclopentanes/chemical synthesis/chemistry/*pharmacology, Humans, Molecular Structure, Nucleosides/chemical synthesis/chemistry/*pharmacology, Stereoisomerism
@article{maier_diastereoselective_2017,
title = {Diastereoselective Flexible Synthesis of Carbocyclic C-Nucleosides.},
author = {Lukáš Maier and Prashant Khirsariya and Ondřej Hylse and Santosh Kumar Adla and Lenka Černová and Michal Poljak and Soňa Krajčovičová and Erik Weis and Stanislav Drápela and Karel Souček and Kamil Paruch},
doi = {10.1021/acs.joc.6b02594},
issn = {1520-6904 0022-3263},
year = {2017},
date = {2017-04-01},
journal = {The Journal of organic chemistry},
volume = {82},
number = {7},
pages = {3382–3402},
abstract = {Carbocyclic C-nucleosides are quite rare. Our route enables flexible preparation of three classes of these nucleoside analogs from common precursors-properly substituted cyclopentanones, which can be prepared racemic (in six steps) or optically pure (in ten steps) from inexpensive norbornadiene. The methodology allows flexible manipulation of individual positions around the cyclopentane ring, namely highly diastereoselective installation of carbo- and heterocyclic substituents at position 1', orthogonal functionalization of position 5', and efficient inversion of stereochemistry at position 2'. Newly prepared carbocyclic C-analog of tubercidine, profiled in MCF7 (breast cancer) and HFF1 (human foreskin fibroblasts) cell cultures, is less potent than tubercidine itself, but more selectively toxic toward the tumorigenic cells.},
note = {Place: United States},
keywords = {Cell Proliferation/drug effects, Cells, Cultured, Cyclopentanes/chemical synthesis/chemistry/*pharmacology, Humans, Molecular Structure, Nucleosides/chemical synthesis/chemistry/*pharmacology, Stereoisomerism},
pubstate = {published},
tppubtype = {article}
}
2014
Uhlik, Ondrej; Strejcek, Michal; Vondracek, Jan; Musilova, Lucie; Ridl, Jakub; Lovecka, Petra; Macek, Tomas
Bacterial acquisition of hexachlorobenzene-derived carbon in contaminated soil. Journal Article
In: Chemosphere, vol. 113, pp. 141–145, 2014, ISSN: 1879-1298 0045-6535, (Place: England).
Abstract | Links | BibTeX | Tags: *Soil Microbiology, 16S rRNA genes, 16S/genetics, Amplicon pyrosequencing, Biodegradation, Bioremediation, Carbon Isotopes/metabolism, Czech Republic, DNA, DNA Primers, Environmental, Hexachlorobenzene/chemistry/*metabolism, Isotope Labeling, Methylobacterium/*metabolism, Mixed Function Oxygenases/metabolism, Molecular Structure, Pentachlorophenol 4-monooxygenase, Pentachlorophenol/chemistry/metabolism, Pesticides, Pseudomonas/*metabolism, Real-Time Polymerase Chain Reaction, Ribosomal, RNA, Sequence Analysis, Soil Pollutants/*metabolism, Stable isotope probing
@article{uhlik_bacterial_2014,
title = {Bacterial acquisition of hexachlorobenzene-derived carbon in contaminated soil.},
author = {Ondrej Uhlik and Michal Strejcek and Jan Vondracek and Lucie Musilova and Jakub Ridl and Petra Lovecka and Tomas Macek},
doi = {10.1016/j.chemosphere.2014.04.110},
issn = {1879-1298 0045-6535},
year = {2014},
date = {2014-10-01},
journal = {Chemosphere},
volume = {113},
pages = {141–145},
abstract = {Pesticides are a class of xenobiotics intentionally released into the environment. Hexachlorobenzene (HCB) was used as a fungicide from 1945, leaving behind many contaminated sites. Very few studies have examined the biodegradation of HCB or the fate of HCB-derived carbon. Here we report that certain bacterial populations are capable of deriving carbon from HCB in contaminated soil under aerobic conditions. These populations are primarily Proteobacteria, including Methylobacterium and Pseudomonas, which predominated as detected by stable isotope probing (SIP) and 16S rRNA gene amplicon pyrosequencing. Due to the nature of SIP, which can be used as a functional method solely for assimilatory processes, it is not possible to elucidate whether these populations metabolized directly HCB or intermediates of its metabolism produced by different populations. The possibility exists that HCB is degraded via the formation of pentachlorophenol (PCP), which is further mineralized. With this in mind, we designed primers to amplify PCP 4-monooxygenase-coding sequences based on the available pcpB gene sequence from Methylobacterium radiotolerans JCM 2831. Based on 16S rRNA gene analysis, organisms closely related to this strain were detected in (13)C-labeled DNA. Using the designed primers, we were able to amplify pcpB genes in both total community DNA and (13)C-DNA. This indicates that HCB might be transformed into PCP before it gets assimilated. In summary, this study is the first report on which bacterial populations benefit from carbon originating in the pesticide HCB in a contaminated soil.},
note = {Place: England},
keywords = {*Soil Microbiology, 16S rRNA genes, 16S/genetics, Amplicon pyrosequencing, Biodegradation, Bioremediation, Carbon Isotopes/metabolism, Czech Republic, DNA, DNA Primers, Environmental, Hexachlorobenzene/chemistry/*metabolism, Isotope Labeling, Methylobacterium/*metabolism, Mixed Function Oxygenases/metabolism, Molecular Structure, Pentachlorophenol 4-monooxygenase, Pentachlorophenol/chemistry/metabolism, Pesticides, Pseudomonas/*metabolism, Real-Time Polymerase Chain Reaction, Ribosomal, RNA, Sequence Analysis, Soil Pollutants/*metabolism, Stable isotope probing},
pubstate = {published},
tppubtype = {article}
}
2006
Vondrácek, Jan; Svihálková-Sindlerová, Lenka; Pencíková, Katerina; Krcmár, Pavel; Andrysík, Zdenek; Chramostová, Katerina; Marvanová, Sona; Valovicová, Zuzana; Kozubík, Alois; Gábelová, Alena; Machala, Miroslav
In: Mutation research, vol. 596, no. 1-2, pp. 43–56, 2006, ISSN: 0027-5107, (Place: Netherlands).
Abstract | Links | BibTeX | Tags: Animals, Aryl Hydrocarbon Hydroxylases/genetics, Base Sequence, Carbazoles/*toxicity, Carcinogens/*toxicity, Cell Death/drug effects, Cytochrome P-450 CYP1A1/genetics, Cytochrome P-450 CYP1A2/genetics, Cytochrome P-450 CYP1B1, DNA Primers, Epithelial Cells/drug effects/*pathology, Inbred F344, Liver/*cytology/drug effects, Methylation, Molecular Structure, Mutagens, Rats, Reverse Transcriptase Polymerase Chain Reaction
@article{vondracek_7h-dibenzocgcarbazole_2006,
title = {7H-Dibenzo[c,g]carbazole and 5,9-dimethyldibenzo[c,g]carbazole exert multiple toxic events contributing to tumor promotion in rat liver epithelial 'stem-like' cells.},
author = {Jan Vondrácek and Lenka Svihálková-Sindlerová and Katerina Pencíková and Pavel Krcmár and Zdenek Andrysík and Katerina Chramostová and Sona Marvanová and Zuzana Valovicová and Alois Kozubík and Alena Gábelová and Miroslav Machala},
doi = {10.1016/j.mrfmmm.2005.11.005},
issn = {0027-5107},
year = {2006},
date = {2006-04-01},
journal = {Mutation research},
volume = {596},
number = {1-2},
pages = {43–56},
abstract = {Immature liver progenitor cells have been suggested to be an important target of hepatotoxins and hepatocarcinogens. The goal of the present study was to assess the impact of 7H-dibenzo[c,g]carbazole (DBC) and its tissue-specific carcinogenic N-methyl (N-MeDBC) and 5,9-dimethyl (DiMeDBC) derivatives on rat liver epithelial WB-F344 cells, in vitro model of liver progenitor cells. We investigated the cellular events associated with both tumor initiation and promotion, such as activation of aryl hydrocarbon receptor (AhR), changes in expression of enzymes involved in metabolic activation of DBC and its derivatives, effects on cell cycle, cell proliferation/apoptosis and inhibition of gap junctional intercellular communication (GJIC). N-MeDBC, a tissue-specific sarcomagen, was only a weak inhibitor of GJIC or inducer of AhR-mediated activity, and it did not affect either cell proliferation or apoptosis. DBC was efficient GJIC inhibitor, while DiMeDBC manifested the strongest AhR inducing activity. Accordingly, DiMeDBC was also the most potent inducer of cytochrome P450 1A1 (CYP1A1) and CYP1A2 expression among the three compounds tested. Both DBC and DiMeDBC induced expression of CYP1B1 and aldo-keto reductase 1C9 (AKR1C9). N-MeDBC failed to significantly upregulate CYP1A1/2 and it only moderately increased CYP1B1 or AKR1C9. Only the potent liver carcinogens, DBC and DiMeDBC, caused a significant increase of p53 phosphorylation at Ser15, an increased accumulation of cells in S-phase and apoptosis at micromolar concentrations. In addition, DiMeDBC was found to stimulate cell proliferation of contact-inhibited WB-F344 cells at 1 microM concentration, which is a mode of action that might further contribute to its hepatocarcinogenicity. The present data seem to suggest that the AhR activation, induction of enzymes involved in metabolic activation, inhibition of GJIC or stimulation of cell proliferation might all contribute to the hepatocarcinogenic effects of DBC and DiMeDBC.},
note = {Place: Netherlands},
keywords = {Animals, Aryl Hydrocarbon Hydroxylases/genetics, Base Sequence, Carbazoles/*toxicity, Carcinogens/*toxicity, Cell Death/drug effects, Cytochrome P-450 CYP1A1/genetics, Cytochrome P-450 CYP1A2/genetics, Cytochrome P-450 CYP1B1, DNA Primers, Epithelial Cells/drug effects/*pathology, Inbred F344, Liver/*cytology/drug effects, Methylation, Molecular Structure, Mutagens, Rats, Reverse Transcriptase Polymerase Chain Reaction},
pubstate = {published},
tppubtype = {article}
}
2005
Plísková, Martina; Vondrácek, Jan; Kren, Vladimír; Gazák, Radek; Sedmera, Petr; Walterová, Daniela; Psotová, Jitka; Simánek, Vilím; Machala, Miroslav
Effects of silymarin flavonolignans and synthetic silybin derivatives on estrogen and aryl hydrocarbon receptor activation. Journal Article
In: Toxicology, vol. 215, no. 1-2, pp. 80–89, 2005, ISSN: 0300-483X, (Place: Ireland).
Abstract | Links | BibTeX | Tags: Animals, Aryl Hydrocarbon/*metabolism, Cell Line, Cell Survival/drug effects, Dose-Response Relationship, Drug, Estrogen/*metabolism, Humans, Luciferases/biosynthesis/genetics, Molecular Structure, Rats, Receptors, Silybin, Silymarin/chemistry/pharmacology, Stereoisomerism, Tumor
@article{pliskova_effects_2005,
title = {Effects of silymarin flavonolignans and synthetic silybin derivatives on estrogen and aryl hydrocarbon receptor activation.},
author = {Martina Plísková and Jan Vondrácek and Vladimír Kren and Radek Gazák and Petr Sedmera and Daniela Walterová and Jitka Psotová and Vilím Simánek and Miroslav Machala},
doi = {10.1016/j.tox.2005.06.020},
issn = {0300-483X},
year = {2005},
date = {2005-11-01},
journal = {Toxicology},
volume = {215},
number = {1-2},
pages = {80–89},
abstract = {Silymarin, a standardized mixture of flavonolignans, or its major constituents could be effective for prevention and treatment of hepatic damage or skin cancer. However, their potential side effects, such as modulation of endocrine functions via the disruption of estrogen receptor (ER) and/or aryl hydrocarbon receptor (AhR) activation, are largely unknown. In the present study, we investigated impact of silymarin, its constituents and a series of their synthetic derivatives on ER- and AhR-mediated activities using in vitro reporter gene assays. We found that none of the compounds under study affected the AhR-mediated activity in rat hepatoma cells. Contrary to that, several compounds behaved as either partial or full ER agonists. Silymarin elicited partial ER activation, with silybin B being probably responsible for a majority of the weak ER-mediated activity of silymarin; silybin A and other flavonolignans were found to be inactive and potent ER agonist taxifolin is only a minor constituent of silymarin. To our knowledge, this is probably the first time, when receptor-specific in vitro effects of separated diastereomers have been demonstrated. In contrast to silymarin constituents, the synthetic silybin derivatives, potentially useful as chemoprotective agents, did not modulate the ER-mediated activity, with exception of 23-O-pivaloylsilybin. Interestingly, 7-O-benzylsilybin potentiated ER-mediated activity of 17beta-estradiol despite possessing no estrogenic activity. In conclusion, our data suggest that estrogenicity of some silymarin constituents should be taken in account as their potential side effect when considered as chemopreventive compounds. These results also stress the need to study biological activities of purified or synthesized diastereomers of silybin derivatives.},
note = {Place: Ireland},
keywords = {Animals, Aryl Hydrocarbon/*metabolism, Cell Line, Cell Survival/drug effects, Dose-Response Relationship, Drug, Estrogen/*metabolism, Humans, Luciferases/biosynthesis/genetics, Molecular Structure, Rats, Receptors, Silybin, Silymarin/chemistry/pharmacology, Stereoisomerism, Tumor},
pubstate = {published},
tppubtype = {article}
}
2004
Vondrácek, Jan; Chramostová, Katerina; Plísková, Martina; Bláha, Ludek; Brack, Werner; Kozubík, Alois; Machala, Miroslav
In: Environmental toxicology and chemistry, vol. 23, no. 9, pp. 2214–2220, 2004, ISSN: 0730-7268, (Place: United States).
Abstract | Links | BibTeX | Tags: Animals, Aryl Hydrocarbon/*drug effects, Carcinogens, Cell Count, Cell Line, Cell Proliferation/drug effects, Environmental/*pharmacology, Estrogen/*drug effects, Estrogens/*pharmacology, Furans/*pharmacology, Molecular Structure, Naphthalenes/*pharmacology, Rats, Receptors, S Phase/drug effects, Tumor
@article{vondracek_induction_2004,
title = {Induction of aryl hydrocarbon receptor-mediated and estrogen receptor-mediated activities, and modulation of cell proliferation by dinaphthofurans.},
author = {Jan Vondrácek and Katerina Chramostová and Martina Plísková and Ludek Bláha and Werner Brack and Alois Kozubík and Miroslav Machala},
doi = {10.1897/03-620},
issn = {0730-7268},
year = {2004},
date = {2004-09-01},
journal = {Environmental toxicology and chemistry},
volume = {23},
number = {9},
pages = {2214–2220},
abstract = {A group of heterocyclic aromatic compounds, dinaphthofurans (DNFs), recently have been identified as potentially significant contaminants in freshwater sediments. In the present study, a battery of in vitro assays was used for detection of toxic effects of DNFs that are potentially associated with endocrine disruption and tumor promotion. Dinaphthofurans were found to act as relatively potent inducers of aryl hydrocarbon receptor (AhR)-mediated activity in the chemical-activated luciferase reporter gene expression DR-CALUX assay. The relative AhR-inducing potencies of DNFs were similar or even higher than relative potencies of unsubstituted polycyclic aromatic hydrocarbons (PAHs), with dinaphtho[1,2-b;2'3'-d]furan being the most potent AhR agonist. Two compounds, dinaphtho[2,1-b;2'3'-d]furan and dinaphtho[1,2-b;1'2'-d]furan, induced estrogen receptor (ER)-mediated activity in the estrogen receptor-mediated CALUX (the ER-CALUX) assay. Two types of potential tumor-promoting effects of DNFs were investigated, using in vitro bioassays for detection of inhibition of gap-junctional intercellular communication and detection of a release from contact inhibition. Although the acute inhibition of gap-junctional intercellular communication was not observed, all six tested DNFs were able to release rat liver epithelial WB-F344 cells from contact inhibition at concentrations as low as 100 nM. In summary, the present study indicated that DNFs can exert multiple biological effects in vitro, including induction of the AhR-mediated activity, release of cells from contact inhibition, and induction of ER-mediated activity.},
note = {Place: United States},
keywords = {Animals, Aryl Hydrocarbon/*drug effects, Carcinogens, Cell Count, Cell Line, Cell Proliferation/drug effects, Environmental/*pharmacology, Estrogen/*drug effects, Estrogens/*pharmacology, Furans/*pharmacology, Molecular Structure, Naphthalenes/*pharmacology, Rats, Receptors, S Phase/drug effects, Tumor},
pubstate = {published},
tppubtype = {article}
}
2002
Bláha, Ludek; Kapplová, Petra; Vondrácek, Jan; Upham, Brad; Machala, Miroslav
Inhibition of gap-junctional intercellular communication by environmentally occurring polycyclic aromatic hydrocarbons. Journal Article
In: Toxicological sciences : an official journal of the Society of Toxicology, vol. 65, no. 1, pp. 43–51, 2002, ISSN: 1096-6080 1096-0929, (Place: United States).
Abstract | Links | BibTeX | Tags: Animals, Carcinogens/toxicity, Cell Communication/*drug effects, Cell Line, Dose-Response Relationship, Drug, Environmental Pollutants/*toxicity, Epithelium/drug effects, Gap Junctions/*drug effects, Liver/cytology/drug effects, Molecular Structure, Polycyclic Aromatic Hydrocarbons/chemistry/*toxicity, Rats, Tetradecanoylphorbol Acetate/toxicity, United States, United States Environmental Protection Agency/standards
@article{blaha_inhibition_2002,
title = {Inhibition of gap-junctional intercellular communication by environmentally occurring polycyclic aromatic hydrocarbons.},
author = {Ludek Bláha and Petra Kapplová and Jan Vondrácek and Brad Upham and Miroslav Machala},
doi = {10.1093/toxsci/65.1.43},
issn = {1096-6080 1096-0929},
year = {2002},
date = {2002-01-01},
journal = {Toxicological sciences : an official journal of the Society of Toxicology},
volume = {65},
number = {1},
pages = {43–51},
abstract = {Polycyclic aromatic hydrocarbons (PAHs) are a broad class of ubiquitous environmental pollutants with known or suspected carcinogenic properties. Tumor promotion is a cell-proliferative step of cancer that requires the removal of cells from growth suppression via the inhibition of gap-junctional intercellular communication (GJIC). Inhibition of GJIC measured with an in vitro WB-F344 rat liver epithelial cell system was used to assess the relative potencies of 13 PAHs suggested by the U.S. Environmental Protection Agency (EPA) as the principal contaminants and 22 other PAHs, most of them identified in environmental samples. Maximal inhibition of GJIC was detected after 30 min of exposure, followed by a recovery in intercellular communication after an additional 30 min of exposure, suggesting a transient character of inhibition. Although microM concentrations of PAHs were required to reach the inhibition level equal to the model tumor promoter phorbol 12-myristate 13-acetate (IC50 = 8 nM), 12 of the PAHs under study were found to be strong inhibitors of GJIC (strongest effects were observed with fluoranthene, picene, 5-methylchrysene and nine additional PAHs). The other nine PAHs, including benzo[a]pyrene, inhibited GJIC only up to 50-75% of the control level. Interestingly, several high molecular weight PAHs with known strong carcinogenic properties possessed only weak (dibenzopyrenes) or no inhibition potency (dibenzofluoranthenes, naphtho[2,3-a]pyrene and benzo[a]perylene). Based on the IC50 values related to the reference PAH benzo[a]pyrene, we suggested arbitrary values of inhibition equivalency factors (GJIC-IEFs) ranging from 0 (noninhibiting PAHs) to 10.0 (strongest inhibitors), suitable for the purposes of environmental risk assessment.},
note = {Place: United States},
keywords = {Animals, Carcinogens/toxicity, Cell Communication/*drug effects, Cell Line, Dose-Response Relationship, Drug, Environmental Pollutants/*toxicity, Epithelium/drug effects, Gap Junctions/*drug effects, Liver/cytology/drug effects, Molecular Structure, Polycyclic Aromatic Hydrocarbons/chemistry/*toxicity, Rats, Tetradecanoylphorbol Acetate/toxicity, United States, United States Environmental Protection Agency/standards},
pubstate = {published},
tppubtype = {article}
}