Latest Publications

@article{valcikova_eif4f_2024,

title = {eIF4F controls ERK MAPK signaling in melanomas with BRAF and NRAS mutations.},

author = {Barbora Valcikova and Natalia Vadovicova and Karolina Smolkova and Magdalena Zacpalova and Pavel Krejci and Shannon Lee and Jens Rauch and Walter Kolch and Alexander Kriegsheim and Anna Dorotikova and Zdenek Andrysik and Rachel Vichova and Ondrej Vacek and Karel Soucek and Stjepan Uldrijan},

doi = {10.1073/pnas.2321305121},

issn = {1091-6490 0027-8424},

year  = {2024},

date = {2024-10-01},

journal = {Proceedings of the National Academy of Sciences of the United States of America},

volume = {121},

number = {44},

pages = {e2321305121},

abstract = {The eIF4F translation initiation complex plays a critical role in melanoma resistance to clinical BRAF and MEK inhibitors. In this study, we uncover a function of eIF4F in the negative regulation of the rat sarcoma (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) signaling pathway. We demonstrate that eIF4F is essential for controlling ERK signaling intensity in treatment-naïve melanoma cells harboring BRAF or NRAS mutations. Specifically, the dual-specificity phosphatase DUSP6/MKP3, which acts as a negative feedback regulator of ERK activity, requires continuous production in an eIF4F-dependent manner to limit excessive ERK signaling driven by oncogenic RAF/RAS mutations. Treatment with small-molecule eIF4F inhibitors disrupts the negative feedback control of MAPK signaling, leading to ERK hyperactivation and EGR1 overexpression in melanoma cells in vitro and in vivo. Furthermore, our quantitative analyses reveal a high spare signaling capacity in the ERK pathway, suggesting that eIF4F-dependent feedback keeps the majority of ERK molecules inactive under normal conditions. Overall, our findings highlight the crucial role of eIF4F in regulating ERK signaling flux and suggest that pharmacological eIF4F inhibitors can disrupt the negative feedback control of MAPK activity in melanomas with BRAF and NRAS activating mutations.},

note = {Place: United States},

keywords = {*Eukaryotic Initiation Factor-4F/metabolism/genetics, *GTP Phosphohydrolases/metabolism/genetics, *MAP Kinase Signaling System/genetics, *Melanoma/genetics/metabolism/pathology, *Membrane Proteins/metabolism/genetics, *Mutation, *Proto-Oncogene Proteins B-raf/genetics/metabolism, Animals, Cell Line, Dual Specificity Phosphatase 6/metabolism/genetics, DUSP6, eIF4F, ERK, Extracellular Signal-Regulated MAP Kinases/metabolism, Humans, MAP kinase, Melanoma, Mice, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{besse_hiv-protease_2024,

title = {HIV-protease inhibitors potentiate the activity of carfilzomib in triple-negative breast cancer.},

author = {Andrej Besse and Lenka Sedlarikova and Lorina Buechler and Marianne Kraus and Chieh-Hsiang Yang and Nicol Strakova and Karel Soucek and Jiri Navratil and Marek Svoboda and Alana L. Welm and Markus Joerger and Christoph Driessen and Lenka Besse},

doi = {10.1038/s41416-024-02774-9},

issn = {1532-1827 0007-0920},

year  = {2024},

date = {2024-09-01},

journal = {British journal of cancer},

volume = {131},

number = {5},

pages = {918–930},

abstract = {BACKGROUND: Resistance to chemotherapy is a major problem in the treatment of patients with triple-negative breast cancer (TNBC). Preclinical data suggest that TNBC is dependent on proteasomes; however, clinical observations indicate that the efficacy of proteasome inhibitors in TNBC may be limited, suggesting the need for combination therapies. METHODS: We compared bortezomib and carfilzomib and their combinations with nelfinavir and lopinavir in TNBC cell lines and primary cells with regard to their cytotoxic activity, functional proteasome inhibition, and induction of the unfolded protein response (UPR). Furthermore, we evaluated the involvement of sXBP1, ABCB1, and ABCG2 in the cytotoxic activity of drug combinations. RESULTS: Carfilzomib, via proteasome β5 + β2 inhibition, is more cytotoxic in TNBC than bortezomib, which inhibits β5 + β1 proteasome subunits. The cytotoxicity of carfilzomib was significantly potentiated by nelfinavir or lopinavir. Carfilzomib with lopinavir induced endoplasmic reticulum stress and pro-apoptotic UPR through the accumulation of excess proteasomal substrate protein in TNBC in vitro. Moreover, lopinavir increased the intracellular availability of carfilzomib by inhibiting carfilzomib export from cells that express high levels and activity of ABCB1, but not ABCG2. CONCLUSION: Proteasome inhibition by carfilzomib combined with nelfinavir/lopinavir represents a potential treatment option for TNBC, warranting further investigation.},

note = {Place: England},

keywords = {*ATP Binding Cassette Transporter, *Bortezomib/pharmacology, *Drug Synergism, *HIV Protease Inhibitors/pharmacology, *Lopinavir/pharmacology, *Nelfinavir/pharmacology, *Oligopeptides/pharmacology, *Triple Negative Breast Neoplasms/drug therapy/pathology, *Unfolded Protein Response/drug effects, Antineoplastic Combined Chemotherapy Protocols/pharmacology, Apoptosis/drug effects, ATP Binding Cassette Transporter, Cell Line, Endoplasmic Reticulum Stress/drug effects, Female, Humans, Member 2/metabolism/antagonists & inhibitors, Neoplasm Proteins/antagonists & inhibitors/metabolism, Proteasome Inhibitors/pharmacology, Subfamily B/metabolism, Subfamily G, Tumor, X-Box Binding Protein 1/metabolism/genetics},

pubstate = {published},

tppubtype = {article}

}

@article{kvokackova_single-cell_2023,

title = {Single-cell protein profiling defines cell populations associated with triple-negative breast cancer aggressiveness.},

author = {Barbora Kvokačková and Radek Fedr and Daniela Kužílková and Jan Stuchlý and Adéla Vávrová and Jiří Navrátil and Pavel Fabian and Róbert Ondruššek and Petra Ovesná and Ján Remšík and Jan Bouchal and Tomáš Kalina and Karel Souček},

doi = {10.1002/1878-0261.13365},

issn = {1878-0261 1574-7891},

year  = {2023},

date = {2023-06-01},

journal = {Molecular oncology},

volume = {17},

number = {6},

pages = {1024–1040},

abstract = {Triple-negative breast cancer (TNBC) is an aggressive and complex subtype of breast cancer that lacks targeted therapy. TNBC manifests characteristic, extensive intratumoral heterogeneity that promotes disease progression and influences drug response. Single-cell techniques in combination with next-generation computation provide an unprecedented opportunity to identify molecular events with therapeutic potential. Here, we describe the generation of a comprehensive mass cytometry panel for multiparametric detection of 23 phenotypic markers and 13 signaling molecules. This single-cell proteomic approach allowed us to explore the landscape of TNBC heterogeneity, with particular emphasis on the tumor microenvironment. We prospectively profiled freshly resected tumors from 26 TNBC patients. These tumors contained phenotypically distinct subpopulations of cancer and stromal cells that were associated with the patient's clinical status at the time of surgery. We further classified the epithelial-mesenchymal plasticity of tumor cells, and molecularly defined phenotypically diverse populations of tumor-associated stroma. Furthermore, in a retrospective tissue-microarray TNBC cohort, we showed that the level of CD97 at the time of surgery has prognostic potential.},

note = {Place: United States},

keywords = {*Triple Negative Breast Neoplasms/metabolism, Cell Line, Humans, mass cytometry, phenotypic plasticity, Proteomics, Retrospective Studies, Signal Transduction, single-cell profiles, Stromal Cells/metabolism, triple-negative breast cancer, Tumor, tumor heterogeneity, Tumor microenvironment, unsupervised machine learning algorithm},

pubstate = {published},

tppubtype = {article}

}

@article{muresan_toll-like_2022,

title = {Toll-Like Receptor 3 Overexpression Induces Invasion of Prostate Cancer Cells, whereas Its Activation Triggers Apoptosis.},

author = {Ximena M. Muresan and Eva Slabáková and Jiřina Procházková and Stanislav Drápela and Radek Fedr and Markéta Pícková and Ondřej Vacek and Ráchel Víchová and Tereza Suchánková and Jan Bouchal and Daniela Kürfürstová and Milan Král and Tereza Hulínová and Radek P. Sýkora and Vladimír Študent and Václav Hejret and Wytske M. Weerden and Martin Puhr and Václav Pustka and David Potěšil and Zbyněk Zdráhal and Zoran Culig and Karel Souček},

doi = {10.1016/j.ajpath.2022.05.009},

issn = {1525-2191 0002-9440},

year  = {2022},

date = {2022-09-01},

journal = {The American journal of pathology},

volume = {192},

number = {9},

pages = {1321–1335},

abstract = {Toll-like receptor 3 (TLR3) is an endosomal receptor expressed in several immune and epithelial cells. Recent studies have highlighted its expression also in solid tumors, including prostate cancer (PCa), and have described its role primarily in the proinflammatory response and induction of apoptosis. It is up-regulated in some castration-resistant prostate cancers. However, the role of TLR3 in prostate cancer progression remains largely unknown. The current study experimentally demonstrated that exogenous TLR3 activation in PCa cell lines leads to a significant induction of secretion of the cytokines IL-6, IL-8, and interferon-β, depending on the model and chemoresistance status. Transcriptomic analysis of TLR3-overexpressing cells revealed a functional program that is enriched for genes involved in the regulation of cell motility, migration, and tumor invasiveness. Increased motility, migration, and invasion in TLR3-overexpressing cell line were confirmed by several in vitro assays and using an orthotopic prostate xenograft model in vivo. Furthermore, TLR3-ligand induced apoptosis via cleavage of caspase-3/7 and poly (ADP-ribose) polymerase, predominantly in TLR3-overexpressing cells. These results indicate that TLR3 may be involved in prostate cancer progression and metastasis; however, it might also represent an Achilles heel of PCa, which can be exploited for targeted therapy.},

note = {Place: United States},

keywords = {*Prostatic Neoplasms/pathology, *Toll-Like Receptor 3/genetics/metabolism, Animals, Apoptosis, Cell Line, Humans, Male, Poly I-C/pharmacology, Prostate/pathology, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{rihova_transcription_2022,

title = {Transcription factor c-Myb: novel prognostic factor in osteosarcoma.},

author = {Kamila Říhová and Monika Dúcka and Iva Staniczková Zambo and Ladislava Vymětalová and Martin Šrámek and Filip Trčka and Jan Verner and Stanislav Drápela and Radek Fedr and Tereza Suchánková and Barbora Pavlatovská and Eva Ondroušková and Irena Kubelková and Danica Zapletalová and Štěpán Tuček and Peter Múdry and Dagmar Adámková Krákorová and Lucia Knopfová and Jan Šmarda and Karel Souček and Lubor Borsig and Petr Beneš},

doi = {10.1007/s10585-021-10145-4},

issn = {1573-7276 0262-0898},

year  = {2022},

date = {2022-04-01},

journal = {Clinical & experimental metastasis},

volume = {39},

number = {2},

pages = {375–390},

abstract = {The transcription factor c-Myb is an oncoprotein promoting cell proliferation and survival when aberrantly activated/expressed, thus contributing to malignant transformation. Overexpression of c-Myb has been found in leukemias, breast, colon and adenoid cystic carcinoma. Recent studies revealed its expression also in osteosarcoma cell lines and suggested its functional importance during bone development. However, the relevance of c-Myb in control of osteosarcoma progression remains unknown. A retrospective clinical study was carried out to assess a relationship between c-Myb expression in archival osteosarcoma tissues and prognosis in a cohort of high-grade osteosarcoma patients. In addition, MYB was depleted in metastatic osteosarcoma cell lines SAOS-2 LM5 and 143B and their growth, chemosensitivity, migration and metastatic activity were determined. Immunohistochemical analysis revealed that high c-Myb expression was significantly associated with poor overall survival in the cohort and metastatic progression in young patients. Increased level of c-Myb was detected in metastatic osteosarcoma cell lines and its depletion suppressed their growth, colony-forming capacity, migration and chemoresistance in vitro in a cell line-dependent manner. MYB knock-out resulted in reduced metastatic activity of both SAOS-2 LM5 and 143B cell lines in immunodeficient mice. Transcriptomic analysis revealed the c-Myb-driven functional programs enriched for genes involved in the regulation of cell growth, stress response, cell adhesion and cell differentiation/morphogenesis. Wnt signaling pathway was identified as c-Myb target in osteosarcoma cells. Taken together, we identified c-Myb as a negative prognostic factor in osteosarcoma and showed its involvement in the regulation of osteosarcoma cell growth, chemosensitivity, migration and metastatic activity.},

note = {Place: Netherlands},

keywords = {*Bone Neoplasms/pathology, *Osteosarcoma/pathology, Animals, c-Myb, Cell Line, Cell Movement/genetics, Cell Proliferation, Chemoresistance, Gene Expression Regulation, Humans, Metastasis, Mice, Neoplastic, Osteosarcoma, Prognosis, proliferation, Retrospective Studies, Tumor, Wnt Signaling Pathway},

pubstate = {published},

tppubtype = {article}

}

@article{krkoska_role_2022,

title = {Role of miR-653 and miR-29c in downregulation of CYP1A2 expression in hepatocellular carcinoma.},

author = {Martin Krkoška and Jana Nekvindová and Kateřina Nevědělová and Veronika Zubáňová and Lenka Radová and Jan Vondráček and Jarmila Herůdková and Ondřej Slabý and Igor Kiss and Lucia Bohovicová and Pavel Fabian and Zuzana Tylichová and Zdeněk Kala and Petr Kysela and Lenka Ostřížková and Vladimír Palička and Alena Hyršlová Vaculová},

doi = {10.1007/s43440-021-00338-9},

issn = {2299-5684 1734-1140},

year  = {2022},

date = {2022-02-01},

journal = {Pharmacological reports : PR},

volume = {74},

number = {1},

pages = {148–158},

abstract = {BACKGROUND: Hepatocellular carcinoma (HCC) is a major contributor to the worldwide cancer burden. Recent studies on HCC have demonstrated dramatic alterations in expression of several cytochrome P450 (CYP) family members that play a crucial role in biotransformation of many drugs and other xenobiotics; however, the mechanisms responsible for their deregulation remain unclear. METHODS: We investigated a potential involvement of miRNAs in downregulation of expression of CYPs observed in HCC tumors. We compared miRNA expression profiles (TaqMan Array Human MicroRNA v3.0 TLDA qPCR) between HCC human patient tumors with strong (CYP-) and weak/no (CYP+) downregulation of drug-metabolizing CYPs. The role of significantly deregulated miRNAs in modulation of expression of the CYPs and associated xenobiotic receptors was then investigated in human liver HepaRG cells transfected with relevant miRNA mimics or inhibitors. RESULTS: We identified five differentially expressed miRNAs in CYP- versus CYP+ tumors, namely miR-29c, miR-125b1, miR-505, miR-653 and miR-675. The two most-upregulated miRNAs found in CYP- tumor samples, miR-29c and miR-653, were found to act as efficient suppressors of CYP1A2 or AHR expression. CONCLUSIONS: Our results revealed a novel role of miR-653 and miR-29c in regulation of expresion of CYPs involved in crucial biotransformation processes in liver, which are often deregulated during liver cancer progression.},

note = {Place: Switzerland},

keywords = {*Carcinoma, *Liver Neoplasms/genetics/metabolism, AhR, Biotransformation, Cell Line, CYP1A2, Cytochrome P-450 CYP1A2/*metabolism, Down-Regulation, Gene Expression Regulation, Hepatocellular carcinoma, Hepatocellular/genetics/metabolism, Hepatocytes/metabolism, Humans, MicroRNA, MicroRNAs/*metabolism, Neoplastic, Tumor, Xenobiotics/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{krkoska_deregulation_2021,

title = {Deregulation of signaling pathways controlling cell survival and proliferation in cancer cells alters induction of cytochrome P450 family 1 enzymes.},

author = {Martin Krkoška and Jana Svobodová and Markéta Kabátková and Ondřej Zapletal and Alena Hyršlová Vaculová and Jana Nekvindová and Jan Vondráček},

doi = {10.1016/j.tox.2021.152897},

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

year  = {2021},

date = {2021-09-01},

journal = {Toxicology},

volume = {461},

pages = {152897},

abstract = {Cytochrome P450 family 1 (CYP1) enzymes contribute both to metabolism of xenobiotics and to the control of endogenous levels of ligands of the aryl hydrocarbon receptor (AhR). Their activities, similar to other CYPs, can be altered in tumor tissues. Here, we examined a possible role of proliferative/survival pathways signaling, which is often deregulated in tumor cells, and possible links with p300 histone acetyltransferase (a transcriptional co-activator) in the control of CYP1 expression, focusing particularly on CYP1A1. Using cell models derived from human liver, we observed that the induction of CYP1A1 expression, as well as other CYP1 enzymes, was reduced in exponentially growing cells, as compared with their non-dividing counterparts. The siRNA-mediated inhibition of proliferation/pro-survival signaling pathway effectors (such as β-catenin and/or Hippo pathway effectors YAP/TAZ) increased the AhR ligand-induced CYP1A1 mRNA levels in liver HepaRG cells, and/or in colon carcinoma HCT-116 cells. The activation of proliferative Wnt/β-catenin signaling in HCT-116 cells reduced both the induction of CYP1 enzymes and the binding of p300 to the promoter of CYP1A1 or CYP1B1 genes. These results seem to indicate that aberrant proliferative signaling in tumor cells could suppress induction of CYP1A1 (or other CYP1 enzymes) via competition for p300 binding. This mechanism could be involved in modulation of the metabolism of both endogenous and exogenous substrates of CYP1A1 (and other CYP1 enzymes), with possible further consequences for alterations of the AhR signaling in tumor cells, or additional functional roles of CYP1 enzymes.},

note = {Place: Ireland},

keywords = {AhR, Cancer cells, Cell Line, Cell Proliferation, Cell Proliferation/*physiology, Cell Survival/physiology, Colonic Neoplasms/genetics/*pathology, CYP1 enzymes, Cytochrome P-450 CYP1A1/biosynthesis/*genetics, E1A-Associated p300 Protein/metabolism, Enzyme Induction/physiology, Gene Expression Regulation, HCT116 Cells, Hippo Signaling Pathway/physiology, Humans, Liver/*pathology, Neoplastic, p300, Signal Transduction/physiology, Tumor, Wnt Signaling Pathway/physiology, β-Catenin signaling},

pubstate = {published},

tppubtype = {article}

}

@article{machala_changes_2021,

title = {Changes in Sphingolipid Profile of Benzo[a]pyrene-Transformed Human Bronchial Epithelial Cells Are Reflected in the Altered Composition of Sphingolipids in Their Exosomes.},

author = {Miroslav Machala and Josef Slavík and Ondrej Kováč and Jiřina Procházková and Kateřina Pěnčíková and Martina Pařenicová and Nicol Straková and Jan Kotouček and Pavel Kulich and Steen Mollerup and Jan Vondráček and Martina Hýžďalová},

doi = {10.3390/ijms22179195},

issn = {1422-0067},

year  = {2021},

date = {2021-08-01},

journal = {International journal of molecular sciences},

volume = {22},

number = {17},

abstract = {Sphingolipids (SLs), glycosphingolipids (GSLs), and eicosanoids are bioactive lipids, which play important roles in the etiology of various diseases, including cancer. However, their content and roles in cancer cells, and in particular in the exosomes derived from tumor cells, remain insufficiently characterized. In this study, we evaluated alterations of SL and GSL levels in transformed cells and their exosomes, using comparative HPLC-MS/MS analysis of parental human bronchial epithelial cells HBEC-12KT and their derivative, benzo[a]pyrene-transformed HBEC-12KT-B1 cells with the acquired mesenchymal phenotype. We examined in parallel SL/GSL contents in the exosomes released from both cell lines. We found significant alterations of the SL/GSL profile in the transformed cell line, which corresponded well with alterations of the SL/GSL profile in exosomes derived from these cells. This suggested that a majority of SLs and GSLs were transported by exosomes in the same relative pattern as in the cells of origin. The only exceptions included decreased contents of sphingosin, sphingosin-1-phosphate, and lactosylceramide in exosomes derived from the transformed cells, as compared with the exosomes derived from the parental cell line. Importantly, we found increased levels of ceramide phosphate, globoside Gb3, and ganglioside GD3 in the exosomes derived from the transformed cells. These positive modulators of epithelial-mesenchymal transition and other pro-carcinogenic processes might thus also contribute to cancer progression in recipient cells. In addition, the transformed HBEC-12KT-B1 cells also produced increased amounts of eicosanoids, in particular prostaglandin E2. Taken together, the exosomes derived from the transformed cells with specifically upregulated SL and GSL species, and increased levels of eicosanoids, might contribute to changes within the cancer microenvironment and in recipient cells, which could in turn participate in cancer development. Future studies should address specific roles of individual SL and GSL species identified in the present study.},

note = {Place: Switzerland},

keywords = {*Cell Transformation, Benzo(a)pyrene/toxicity, Bronchi/cytology, Carcinogens/toxicity, Cell Line, eicosanoids, exosomes, Exosomes/*metabolism, glycosphingolipid, Humans, in vitro cell transformation, Neoplastic, Respiratory Mucosa/drug effects/*metabolism, sphingolipid, Sphingolipids/*metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{mickova_skp2_2021,

title = {Skp2 and Slug Are Coexpressed in Aggressive Prostate Cancer and Inhibited by Neddylation Blockade.},

author = {Alena Mickova and Gvantsa Kharaishvili and Daniela Kurfurstova and Mariam Gachechiladze and Milan Kral and Ondrej Vacek and Barbora Pokryvkova and Martin Mistrik and Karel Soucek and Jan Bouchal},

doi = {10.3390/ijms22062844},

issn = {1422-0067},

year  = {2021},

date = {2021-03-01},

journal = {International journal of molecular sciences},

volume = {22},

number = {6},

abstract = {Prostate cancer (PCa) is the second leading cause of cancer-related deaths in men in Western countries, and there is still an urgent need for a better understanding of PCa progression to inspire new treatment strategies. Skp2 is a substrate-recruiting component of the E3 ubiquitin ligase complex, whose activity is regulated through neddylation. Slug is a transcriptional repressor involved in the epithelial-to-mesenchymal transition, which may contribute to therapy resistance. Although Skp2 has previously been associated with a mesenchymal phenotype and prostate cancer progression, the relationship with Slug deserves further elucidation. We have previously shown that a high Gleason score (≥8) is associated with higher Skp2 and lower E-cadherin expression. In this study, significantly increased expression of Skp2, AR, and Slug, along with E-cadherin downregulation, was observed in primary prostate cancer in patients who already had lymph node metastases. Skp2 was slightly correlated with Slug and AR in the whole cohort (Rs 0.32 and 0.37, respectively), which was enhanced for both proteins in patients with high Gleason scores (Rs 0.56 and 0.53, respectively) and, in the case of Slug, also in patients with metastasis to lymph nodes (Rs 0.56). Coexpression of Skp2 and Slug was confirmed in prostate cancer tissues by multiplex immunohistochemistry and confocal microscopy. The same relationship between these two proteins was observed in three sets of prostate epithelial cell lines (PC3, DU145, and E2) and their mesenchymal counterparts. Chemical inhibition of Skp2, but not RNA interference, modestly decreased Slug protein in PC3 and its docetaxel-resistant subline PC3 DR12. Importantly, chemical inhibition of Skp2 by MLN4924 upregulated p27 and decreased Slug expression in PC3, PC3 DR12, and LAPC4 cells. Novel treatment strategies targeting Skp2 and Slug by the neddylation blockade may be promising in advanced prostate cancer, as recently documented for other aggressive solid tumors.},

note = {Place: Switzerland},

keywords = {*Protein Processing, Androgen/genetics/metabolism, Antigens, Antineoplastic Agents/pharmacology, Cadherins/genetics/metabolism, CD/genetics/metabolism, Cell Line, Cell Survival/drug effects, Cyclin-Dependent Kinase Inhibitor p27/genetics/metabolism, Cyclopentanes/pharmacology, Docetaxel/pharmacology, Epithelial-Mesenchymal Transition/genetics, Gene Expression Regulation, Humans, Immunohistochemistry, Lymphatic Metastasis, Male, multiplex, NEDD8 Protein/*genetics/metabolism, neddylation, Neoplasm Grading, Neoplastic, PC-3 Cells, Post-Translational, Prostate cancer, Prostate/metabolism/pathology, Prostatic Neoplasms/*genetics/metabolism/pathology, Pyrimidines/pharmacology, Receptors, RNA, S-Phase Kinase-Associated Proteins/antagonists & inhibitors/*genetics/metabolism, Skp2 (S-phase kinase-associated protein 2), Slug, Small Interfering/genetics/metabolism, Snail Family Transcription Factors/*genetics/metabolism, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{drapela_chk1_2020,

title = {The CHK1 inhibitor MU380 significantly increases the sensitivity of human docetaxel-resistant prostate cancer cells to gemcitabine through the induction of mitotic catastrophe.},

author = {Stanislav Drápela and Prashant Khirsariya and Wytske M. Weerden and Radek Fedr and Tereza Suchánková and Diana Búzová and Jan Červený and Aleš Hampl and Martin Puhr and William R. Watson and Zoran Culig and Lumír Krejčí and Kamil Paruch and Karel Souček},

doi = {10.1002/1878-0261.12756},

issn = {1878-0261 1574-7891},

year  = {2020},

date = {2020-10-01},

journal = {Molecular oncology},

volume = {14},

number = {10},

pages = {2487–2503},

abstract = {As treatment options for patients with incurable metastatic castration-resistant prostate cancer (mCRPC) are considerably limited, novel effective therapeutic options are needed. Checkpoint kinase 1 (CHK1) is a highly conserved protein kinase implicated in the DNA damage response (DDR) pathway that prevents the accumulation of DNA damage and controls regular genome duplication. CHK1 has been associated with prostate cancer (PCa) induction, progression, and lethality; hence, CHK1 inhibitors SCH900776 (also known as MK-8776) and the more effective SCH900776 analog MU380 may have clinical applications in the therapy of PCa. Synergistic induction of DNA damage with CHK1 inhibition represents a promising therapeutic approach that has been tested in many types of malignancies, but not in chemoresistant mCRPC. Here, we report that such therapeutic approach may be exploited using the synergistic action of the antimetabolite gemcitabine (GEM) and CHK1 inhibitors SCH900776 and MU380 in docetaxel-resistant (DR) mCRPC. Given the results, both CHK1 inhibitors significantly potentiated the sensitivity to GEM in a panel of chemo-naïve and matched DR PCa cell lines under 2D conditions. MU380 exhibited a stronger synergistic effect with GEM than clinical candidate SCH900776. MU380 alone or in combination with GEM significantly reduced spheroid size and increased apoptosis in all patient-derived xenograft 3D cultures, with a higher impact in DR models. Combined treatment induced premature mitosis from G1 phase resulting in the mitotic catastrophe as a prestage of apoptosis. Finally, treatment by MU380 alone, or in combination with GEM, significantly inhibited tumor growth of both PC339-DOC and PC346C-DOC xenograft models in mice. Taken together, our data suggest that metabolically robust and selective CHK1 inhibitor MU380 can bypass docetaxel resistance and improve the effectiveness of GEM in DR mCRPC models. This approach might allow for dose reduction of GEM and thereby minimize undesired toxicity and may represent a therapeutic option for patients with incurable DR mCRPC.},

note = {Place: United States},

keywords = {*Mitosis/drug effects, Animals, castration-resistant prostate cancer, Cell Death/drug effects, Cell Line, Cell Proliferation/drug effects, Checkpoint Kinase 1, Checkpoint Kinase 1/*antagonists & inhibitors/metabolism, Deoxycytidine/*analogs & derivatives/pharmacology, Docetaxel resistance, Docetaxel/*pharmacology, Drug resistance, gemcitabine, Humans, Male, Mice, mitotic catastrophe, MU380, Neoplasm/*drug effects, Piperidines/chemistry/*pharmacology, Prostatic Neoplasms/*pathology, Pyrazoles/chemistry/*pharmacology, Pyrimidines/chemistry/*pharmacology, S Phase/drug effects, SCID, Tumor, Xenograft Model Antitumor Assays},

pubstate = {published},

tppubtype = {article}

}

@article{remsik_tgf-_2020,

title = {TGF-β regulates Sca-1 expression and plasticity of pre-neoplastic mammary epithelial stem cells.},

author = {Ján Remšík and Markéta Pícková and Ondřej Vacek and Radek Fedr and Lucia Binó and Aleš Hampl and Karel Souček},

doi = {10.1038/s41598-020-67827-4},

issn = {2045-2322},

year  = {2020},

date = {2020-07-01},

journal = {Scientific reports},

volume = {10},

number = {1},

pages = {11396},

abstract = {The epithelial-mesenchymal plasticity, in tight association with stemness, contributes to the mammary gland homeostasis, evolution of early neoplastic lesions and cancer dissemination. Focused on cell surfaceome, we used mouse models of pre-neoplastic mammary epithelial and cancer stem cells to reveal the connection between cell surface markers and distinct cell phenotypes. We mechanistically dissected the TGF-β family-driven regulation of Sca-1, one of the most commonly used adult stem cell markers. We further provided evidence that TGF-β disrupts the lineage commitment and promotes the accumulation of tumor-initiating cells in pre-neoplastic cells.},

note = {Place: England},

keywords = {Animal/pathology, Animals, Ataxin-1/*metabolism, Breast Neoplasms/genetics/*pathology, Cell Line, Cell Plasticity/genetics, Epithelial Cells/pathology, Epithelial-Mesenchymal Transition/genetics, ErbB-2/genetics, Experimental/genetics/*pathology, Female, Gene Expression Regulation, Humans, Mammary Glands, Mammary Neoplasms, Mice, Neoplastic, Neoplastic Stem Cells/*pathology, Receptor, Recombinant Proteins/genetics/metabolism, Signal Transduction/genetics, Transforming Growth Factor beta/genetics/*metabolism, Tumor/transplantation},

pubstate = {published},

tppubtype = {article}

}

@article{kahounova_slug-expressing_2020,

title = {Slug-expressing mouse prostate epithelial cells have increased stem cell potential.},

author = {Zuzana Kahounová and Ján Remšík and Radek Fedr and Jan Bouchal and Alena Mičková and Eva Slabáková and Lucia Binó and Aleš Hampl and Karel Souček},

doi = {10.1016/j.scr.2020.101844},

issn = {1876-7753 1873-5061},

year  = {2020},

date = {2020-07-01},

journal = {Stem cell research},

volume = {46},

pages = {101844},

abstract = {Deciphering the properties of adult stem cells is crucial for understanding of their role in healthy tissue and in cancer progression as well. Both stem cells and cancer stem cells have shown association with epithelial-to-mesenchymal transition (EMT) in various tissue types. Aiming to investigate the epithelial and mesenchymal phenotypic traits in adult mouse prostate, we sorted subpopulations of basal prostate stem cells (mPSCs) and assessed the expression levels of EMT regulators and markers with custom-designed gene expression array. The population of mPSCs defined by a Lin(-)/Sca-1(+)CD49f(hi)/Trop-2(+) (LSC Trop-2(+)) surface phenotype was enriched in mesenchymal markers, especially EMT master regulator Slug, encoded by the Snai2 gene. To further dissect the role of Slug in mPSCs, we used transgenic Snai2(tm1.1Wbg) reporter mouse strain. Using this model, we confirmed the presence of mesenchymal traits and increase of organoid forming capacity in Slug(+) population of mPSCs. The Slug(+)-derived organoids comprised all prostate epithelial cell types - basal, luminal, and neuroendocrine. Collectively, these data uncover the important role of Slug expression in the physiology of mouse prostate stem cells.},

note = {Place: England},

keywords = {*Epithelial-Mesenchymal Transition, *Prostate, Animals, Cell Line, Cell Movement, Epithelial Cells, epithelial-to-mesenchymal transition, Male, Mice, Organoids, Prostate stem cells, Snai2/Slug, Snail Family Transcription Factors/genetics, stemness, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{vyhlidalova_gut_2020,

title = {Gut Microbial Catabolites of Tryptophan Are Ligands and Agonists of the Aryl Hydrocarbon Receptor: A Detailed Characterization.},

author = {Barbora Vyhlídalová and Kristýna Krasulová and Petra Pečinková and Adéla Marcalíková and Radim Vrzal and Lenka Zemánková and Jan Vančo and Zdeněk Trávníček and Jan Vondráček and Martina Karasová and Sridhar Mani and Zdeněk Dvořák},

doi = {10.3390/ijms21072614},

issn = {1422-0067},

year  = {2020},

date = {2020-04-01},

journal = {International journal of molecular sciences},

volume = {21},

number = {7},

abstract = {We examined the effects of gut microbial catabolites of tryptophan on the aryl hydrocarbon receptor (AhR). Using a reporter gene assay, we show that all studied catabolites are low-potency agonists of human AhR. The efficacy of catabolites differed substantially, comprising agonists with no or low (i3-propionate, i3-acetate, i3-lactate, i3-aldehyde), medium (i3-ethanol, i3-acrylate, skatole, tryptamine), and high (indole, i3-acetamide, i3-pyruvate) efficacies. We displayed ligand-selective antagonist activities by i3-pyruvate, i3-aldehyde, indole, skatole, and tryptamine. Ligand binding assay identified low affinity (skatole, i3-pyruvate, and i3-acetamide) and very low affinity (i3-acrylate, i3-ethanol, indole) ligands of the murine AhR. Indole, skatole, tryptamine, i3-pyruvate, i3-acrylate, and i3-acetamide induced CYP1A1 mRNA in intestinal LS180 and HT-29 cells, but not in the AhR-knockout HT-29 variant. We observed a similar CYP1A1 induction pattern in primary human hepatocytes. The most AhR-active catabolites (indole, skatole, tryptamine, i3-pyruvate, i3-acrylate, i3-acetamide) elicited nuclear translocation of the AhR, followed by a formation of AhR-ARNT heterodimer and enhanced binding of the AhR to the CYP1A1 gene promoter. Collectively, we comprehensively characterized the interactions of gut microbial tryptophan catabolites with the AhR, which may expand the current understanding of their potential roles in intestinal health and disease.},

note = {Place: Switzerland},

keywords = {*Gastrointestinal Microbiome/drug effects, Animals, Aryl hydrocarbon receptor, Aryl Hydrocarbon/*agonists/*metabolism, Basic Helix-Loop-Helix Transcription Factors/*agonists/*metabolism, Cell Line, Cytochrome P-450 CYP1A1/genetics, Gene Expression, Genes, Genetic, Humans, Indoles, Ligands, Metabolic Networks and Pathways, Mice, Microbiome, Promoter Regions, Protein Binding, Protein Multimerization, Receptors, Reporter, tryptophan, Tryptophan/*metabolism, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{hofmanova_phospholipid_2020,

title = {Phospholipid profiling enables to discriminate tumor- and non-tumor-derived human colon epithelial cells: Phospholipidome similarities and differences in colon cancer cell lines and in patient-derived cell samples.},

author = {Jiřina Hofmanová and Josef Slavík and Petra Ovesná and Zuzana Tylichová and Ladislav Dušek and Nicol Straková and Alena Hyršlová Vaculová and Miroslav Ciganek and Zdeněk Kala and Miroslav Jíra and Igor Penka and Jitka Kyclová and Zdeněk Kolář and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.1371/journal.pone.0228010},

issn = {1932-6203},

year  = {2020},

date = {2020-01-01},

journal = {PloS one},

volume = {15},

number = {1},

pages = {e0228010},

abstract = {Identification of changes of phospholipid (PL) composition occurring during colorectal cancer (CRC) development may help us to better understand their roles in CRC cells. Here, we used LC-MS/MS-based PL profiling of cell lines derived from normal colon mucosa, or isolated at distinct stages of CRC development, in order to study alterations of PL species potentially linked with cell transformation. We found that a detailed evaluation of phosphatidylinositol (PI) and phosphatidylserine (PS) classes allowed us to cluster the studied epithelial cell lines according to their origin: i) cells originally derived from normal colon tissue (NCM460, FHC); ii) cell lines derived from colon adenoma or less advanced differentiating adenocarcinoma cells (AA/C1, HT-29); or, iii) cells obtained by in vitro transformation of adenoma cells and advanced colon adenocarcinoma cells (HCT-116, AA/C1/SB10, SW480, SW620). Although we tentatively identified several PS and PI species contributing to cell line clustering, full PI and PS profiles appeared to be a key to the successful cell line discrimination. In parallel, we compared PL composition of primary epithelial (EpCAM-positive) cells, isolated from tumor and adjacent non-tumor tissues of colon cancer patients, with PL profiles of cell lines derived from normal colon mucosa (NCM460) and from colon adenocarcinoma (HCT-116, SW480) cells, respectively. In general, higher total levels of all PL classes were observed in tumor cells. The overall PL profiles of the cell lines, when compared with the respective patient-derived cells, exhibited similarities. Nevertheless, there were also some notable differences in levels of individual PL species. This indicated that epithelial cell lines, derived either from normal colon tissue or from CRC cells, could be employed as models for functional lipidomic analyses of colon cells, albeit with some caution. The biological significance of the observed PL deregulation, or their potential links with specific CRC stages, deserve further investigation.},

note = {Place: United States},

keywords = {*Lipidomics, Cell Line, Colon/*pathology, Colonic Neoplasms/*metabolism/*pathology, Epithelial Cells/*metabolism/pathology, Humans, Phospholipids/*metabolism, Principal Component Analysis, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{svobodova_2378-tetrachlorodibenzo-p-dioxin_2019,

title = {2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Disrupts Control of Cell Proliferation and Apoptosis in a Human Model of Adult Liver Progenitors.},

author = {Jana Svobodová and Jiřina Procházková and Markéta Kabátková and Martin Krkoška and Lenka Šmerdová and Helena Líbalová and Jan Topinka and Jiří Kléma and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.1093/toxsci/kfz202},

issn = {1096-0929},

year  = {2019},

date = {2019-12-01},

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

volume = {172},

number = {2},

pages = {368–384},

abstract = {The aryl hydrocarbon receptor (AhR) activation has been shown to alter proliferation, apoptosis, or differentiation of adult rat liver progenitors. Here, we investigated the impact of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-mediated AhR activation on a human model of bipotent liver progenitors, undifferentiated HepaRG cells. We used both intact undifferentiated HepaRG cells, and the cells with silenced Hippo pathway effectors, yes-associated protein 1 (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), which play key role(s) in tissue-specific progenitor cell self-renewal and expansion, such as in liver, cardiac, or respiratory progenitors. TCDD induced cell proliferation in confluent undifferentiated HepaRG cells; however, following YAP, and, in particular, double YAP/TAZ knockdown, TCDD promoted induction of apoptosis. These results suggested that, unlike in mature hepatocytes, or hepatocyte-like cells, activation of the AhR may sensitize undifferentiated HepaRG cells to apoptotic stimuli. Induction of apoptosis in cells with silenced YAP/TAZ was associated with upregulation of death ligand TRAIL, and seemed to involve both extrinsic and mitochondrial apoptosis pathways. Global gene expression analysis further suggested that TCDD significantly altered expression of constituents and/or transcriptional targets of signaling pathways participating in control of expansion or differentiation of liver progenitors, including EGFR, Wnt/β-catenin, or tumor growth factor-β signaling pathways. TCDD significantly upregulated cytosolic proapoptotic protein BMF (Bcl-2 modifying factor) in HepaRG cells, which could be linked with an enhanced sensitivity of TCDD-treated cells to apoptosis. Our results suggest that, in addition to promotion of cell proliferation and alteration of signaling pathways controlling expansion of human adult liver progenitors, AhR ligands may also sensitize human liver progenitor cells to apoptosis.},

note = {Place: United States},

keywords = {*Models, Adaptor Proteins, Apoptosis, Apoptosis/*drug effects/genetics, Aryl hydrocarbon receptor, Aryl Hydrocarbon/metabolism, Biological, Cell Line, Cell Proliferation, Cell Proliferation/*drug effects/genetics, Gene Expression/drug effects, HepaRG cells, Hippo signaling, Humans, Liver/*drug effects/pathology, Polychlorinated Dibenzodioxins/*toxicity, Receptors, RNA, Signal Transducing/genetics, Signal Transduction, Small Interfering/genetics, Stem Cells/*drug effects/pathology, Trans-Activators/genetics, Transcription Factors/genetics, Transcriptional Coactivator with PDZ-Binding Motif Proteins, Transfection, YAP-Signaling Proteins},

pubstate = {published},

tppubtype = {article}

}

@article{pencikova_modulation_2019,

title = {Modulation of endocrine nuclear receptor activities by polyaromatic compounds present in fractionated extracts of diesel exhaust particles.},

author = {Kateřina Pěnčíková and Miroslav Ciganek and Jiří Neča and Peter Illés and Zdeněk Dvořák and Jan Vondráček and Miroslav Machala},

doi = {10.1016/j.scitotenv.2019.04.390},

issn = {1879-1026 0048-9697},

year  = {2019},

date = {2019-08-01},

journal = {The Science of the total environment},

volume = {677},

pages = {626–636},

abstract = {Organic pollutants associated with diesel exhaust particles (DEP), such as polycyclic aromatic hydrocarbons (PAHs) and their derivatives, may negatively impact human health. However, a comprehensive overview of their effects on endocrine nuclear receptor activities is still missing. Here, we evaluated the effects of extracts and chromatographic fractions (fractionated according to increasing polarity) of two standard reference materials derived from distinct types of diesel engines (SRM 2975, SRM 1650b), on activation of androgen receptor (AR), estrogen receptor alpha (ERα), peroxisome proliferator-activated receptor γ (PPARγ), glucocorticoid receptor (GR) and thyroid receptor α (TRα), using human cell-based reporter gene assays. Neither DEP standard modulated AR or GR activities. Crude extracts and fractions of SRM 1650b and SRM 2975 suppressed ERα-mediated activity in the ER-CALUX™ assay; however, this effect could be partly linked to their cytotoxicity in this cell line. We observed that only SRM 2975 extract and its fractions were partial PPARγ inducers, while SRM 1650b extract was not active towards this receptor. Importantly, we found that both extracts and polar fractions of SRM activated TRα and significantly potentiated the activity of endogenous TRα ligand, triiodothyronine. Based on a detailed chemical analysis of both extracts and their polar fractions, we identified several oxygenated PAH derivatives, that were present at relatively high levels in the analyzed DEP standards, including 3-nitrobenzanthrone (3-NBA), anthracene-9,10-dione, phenanthrene-9,10-dione, 9H-fluoren-9-one or benzo[a]anthracene-7,12-dione, to activate TRα activity. Nevertheless, these compounds provided only a minor contribution to the overall TRα activity identified in polar fractions. This suggests that yet unidentified polar polyaromatic compounds associated with DEP may, apart from their known impact on the aryl hydrocarbon receptor or steroid signaling, deregulate activities of additional nuclear receptors, in particular of TRα. This illustrates the need to better characterize endocrine disrupting activities of DEP.},

note = {Place: Netherlands},

keywords = {*Vehicle Emissions, Air Pollutants/*adverse effects, Androgen receptor, Cell Line, Cytoplasmic and Nuclear/*genetics/metabolism, Diesel exhaust particles, Estrogen receptor α, Glucocorticoid receptor, Humans, Particulate Matter/*adverse effects, Peroxisome proliferator-activated receptor γ, Polycyclic Aromatic Hydrocarbons/*adverse effects, Receptors, Thyroid receptor α},

pubstate = {published},

tppubtype = {article}

}

@article{simeckova_high_2019,

title = {High Skp2 expression is associated with a mesenchymal phenotype and increased tumorigenic potential of prostate cancer cells.},

author = {Šárka Šimečková and Zuzana Kahounová and Radek Fedr and Ján Remšík and Eva Slabáková and Tereza Suchánková and Jiřina Procházková and Jan Bouchal and Gvantsa Kharaishvili and Milan Král and Petr Beneš and Karel Souček},

doi = {10.1038/s41598-019-42131-y},

issn = {2045-2322},

year  = {2019},

date = {2019-04-01},

journal = {Scientific reports},

volume = {9},

number = {1},

pages = {5695},

abstract = {Skp2 is a crucial component of SCF(Skp2) E3 ubiquitin ligase and is often overexpressed in various types of cancer, including prostate cancer (PCa). The epithelial-to-mesenchymal transition (EMT) is involved in PCa progression. The acquisition of a mesenchymal phenotype that results in a cancer stem cell (CSC) phenotype in PCa was described. Therefore, we aimed to investigate the expression and localization of Skp2 in clinical samples from patients with PCa, the association of Skp2 with EMT status, and the role of Skp2 in prostate CSC. We found that nuclear expression of Skp2 was increased in patients with PCa compared to those with benign hyperplasia, and correlated with high Gleason score in PCa patients. Increased Skp2 expression was observed in PCa cell lines with mesenchymal and CSC-like phenotype compared to their epithelial counterparts. Conversely, the CSC-like phenotype was diminished in cells in which SKP2 expression was silenced. Furthermore, we observed that Skp2 downregulation led to the decrease in subpopulation of CD44(+)CD24(-) cancer stem-like cells. Finally, we showed that high expression levels of both CD24 and CD44 were associated with favorable recurrence-free survival for PCa patients. This study uncovered the Skp2-mediated CSC-like phenotype with oncogenic functions in PCa.},

note = {Place: England},

keywords = {*Epithelial-Mesenchymal Transition, *Gene Expression Regulation, Animals, CD24 Antigen/genetics, Cell Line, Humans, Hyaluronan Receptors/genetics, Male, Mice, Neoplasm Grading, Neoplastic, Neoplastic Stem Cells/metabolism/*physiology, Nude, PC-3 Cells, Prostatic Neoplasms/*genetics/metabolism/physiopathology, S-Phase Kinase-Associated Proteins/*genetics, Tumor, Xenograft Model Antitumor Assays},

pubstate = {published},

tppubtype = {article}

}

@article{tylichova_n-3_2019,

title = {n-3 Polyunsaturated fatty acids alter benzo[a]pyrene metabolism and genotoxicity in human colon epithelial cell models.},

author = {Zuzana Tylichová and Jiří Neča and Jan Topinka and Alena Milcová and Jiřina Hofmanová and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.1016/j.fct.2018.12.021},

issn = {1873-6351 0278-6915},

year  = {2019},

date = {2019-02-01},

journal = {Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association},

volume = {124},

pages = {374–384},

abstract = {Dietary carcinogens, such as benzo[a]pyrene (BaP), are suspected to contribute to colorectal cancer development. n-3 Polyunsaturated fatty acids (PUFAs) decrease colorectal cancer risk in individuals consuming diets rich in PUFAs. Here, we investigated the impact of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid on metabolism and genotoxicity of BaP in human cell models derived from the colon: HT-29 and HCT-116 cell lines. Both PUFAs reduced levels of excreted BaP metabolites, in particular BaP-tetrols and hydroxylated BaP metabolites, as well as formation of DNA adducts in HT-29 and HCT-116 cells. However, EPA appeared to be a more potent inhibitor of formation of some intracellular BaP metabolites, including BaP-7,8-dihydrodiol. EPA also reduced phosphorylation of histone H2AX (Ser139) in HT-29 cells, which indicated that it may reduce further forms of DNA damage, including DNA double strand breaks. Both PUFAs inhibited induction of CYP1 activity in colon cells determined as 7-ethoxyresorufin-O-deethylase (EROD); this was at least partly linked with inhibition of induction of CYP1A1, 1A2 and 1B1 mRNAs. The downregulation and/or inhibition of CYP1 enzymes by PUFAs could thus alter metabolism and reduce genotoxicity of BaP in human colon cells, which might contribute to known chemopreventive effects of PUFAs in colon epithelium.},

note = {Place: England},

keywords = {Anticarcinogenic Agents/*pharmacology, Benzo(a)pyrene/adverse effects/*metabolism, Cell Line, Colon cancer, Cytochrome P450 Family 1/metabolism, DNA Adducts/metabolism, DNA Damage, DNA Damage/drug effects, Docosahexaenoic acid, Docosahexaenoic Acids/*pharmacology, Eicosapentaenoic acid, Eicosapentaenoic Acid/*pharmacology, Epithelial Cells/*drug effects, Histones/metabolism, Humans, Mutagens/adverse effects/*metabolism, Polycyclic aromatic hydrocarbon, S Phase Cell Cycle Checkpoints/drug effects, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{zapletal_butyrate_2019,

title = {Butyrate interacts with benzo[a]pyrene to alter expression and activities of xenobiotic metabolizing enzymes involved in metabolism of carcinogens within colon epithelial cell models.},

author = {Ondřej Zapletal and Jiřina Procházková and Vít Dubec and Jiřina Hofmanová and Alois Kozubík and Jan Vondráček},

doi = {10.1016/j.tox.2018.11.001},

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

year  = {2019},

date = {2019-01-01},

journal = {Toxicology},

volume = {412},

pages = {1–11},

abstract = {Butyrate helps to maintain colon homeostasis and exhibits chemopreventive effects in colon epithelium. We examined the interactive effects of butyrate and benzo[a]pyrene (BaP), dietary carcinogen, in regulation of expression of a panel of phase I and II xenobiotic metabolizing enzymes (XMEs) in human colon cells. In human colon carcinoma HCT-116 and HT-29 cell lines, butyrate alone increased mRNA levels of some enzymes, such as N-acetyltransferases (in particular NAT2). In combination with BaP, butyrate potentiated induction of cytochrome P450 family 1 enzymes (CYP1A1), aldo-keto reductases (AKR1C1) or UDP-glucuronosyltransferases (UGT1A1). There were some notable differences between cell lines, as butyrate potentiated induction of NAD(P)H:quinone oxidoreductase 1 (NQO1) and UGT1A4 only in HCT-116 cells, and it even repressed AKR1C3 induction in HT-29 cells. Butyrate also promoted induction of CYP1, NQO1, NAT2, UGT1A1 or UGT1A4 in human colon Caco-2 cells, in a differentiation-dependent manner. Differentiated Caco-2 cells exhibited a higher inducibility of selected XME genes than undifferentiated cells. Butyrate increased induction of enzymatic activities of NATs, NQO1 and UGTs by BaP in HCT-116 and HT29 cells, whereas in differentiated Caco-2 cells it helped to increase only enzymatic activity of NQO1 and UGTs. Together, the present data suggest that butyrate may modulate expression/activities of several enzymes involved in metabolism of carcinogens in colon. In some cases (NAT2, UGT1 A1), this was linked to inhibition of histone deacetylases (HDAC), as confirmed by using HDAC inhibitor trichostatin A. These results may have implications for our understanding of the role of butyrate in regulation of XMEs and carcinogen metabolism in colon.},

note = {Place: Ireland},

keywords = {Benzo(a)pyrene/*toxicity, Butyrate, Butyrates/*pharmacology, Carcinogens/*toxicity, Cell Line, Colon epithelium, Colon/cytology, Epithelial Cells/drug effects/metabolism, Humans, N-acetyltransferases, NAD(P)H:quinone oxidoreductase 1, Oxidoreductases/genetics/*metabolism, Polycyclic aromatic hydrocarbons, Transferases/genetics/*metabolism, UDP-glucuronosyltransferases, Xenobiotics/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{remsik_trop-2_2018,

title = {Trop-2 plasticity is controlled by epithelial-to-mesenchymal transition.},

author = {Ján Remšík and Lucia Binó and Zuzana Kahounová and Gvantsa Kharaishvili and Šárka Šimecková and Radek Fedr and Tereza Kucírková and Sára Lenárt and Ximena Maria Muresan and Eva Slabáková and Lucia Knopfová and Jan Bouchal and Milan Král and Petr Beneš and Karel Soucek},

doi = {10.1093/carcin/bgy095},

issn = {1460-2180 0143-3334},

year  = {2018},

date = {2018-12-01},

journal = {Carcinogenesis},

volume = {39},

number = {11},

pages = {1411–1418},

abstract = {The cell surface glycoprotein Trop-2 is commonly overexpressed in carcinomas and represents an exceptional antigen for targeted therapy. Here, we provide evidence that surface Trop-2 expression is functionally connected with an epithelial phenotype in breast and prostate cell lines and in patient tumor samples. We further show that Trop-2 expression is suppressed epigenetically or through the action of epithelial-to-mesenchymal transition transcription factors and that deregulation of Trop-2 expression is linked with cancer progression and poor patient prognosis. Moreover, our data suggest that the cancer plasticity-driven intratumoral heterogeneity in Trop-2 expression may significantly contribute to response and resistance to therapies targeting Trop-2-expressing cells.},

note = {Place: England},

keywords = {Animals, Antigens, Breast Neoplasms/mortality/*pathology, Cadherins/biosynthesis, Carcinoma/*pathology, CD/biosynthesis, Cell Adhesion Molecules/genetics/*metabolism, Cell Line, Disease Progression, DNA Methylation/genetics, Epithelial Cells/*metabolism, Epithelial-Mesenchymal Transition/physiology, Female, Humans, Inbred BALB C, Male, Mice, Neoplasm/genetics/*metabolism, Prostatic Neoplasms/mortality/*pathology, Tumor, Xenograft Model Antitumor Assays},

pubstate = {published},

tppubtype = {article}

}

@article{kahounova_fibroblast_2018,

title = {The fibroblast surface markers FAP, anti-fibroblast, and FSP are expressed by cells of epithelial origin and may be altered during epithelial-to-mesenchymal transition.},

author = {Zuzana Kahounová and Daniela Kurfürstová and Jan Bouchal and Gvantsa Kharaishvili and Jiří Navrátil and Ján Remšík and Šárka Šimečková and Vladimír Študent and Alois Kozubík and Karel Souček},

doi = {10.1002/cyto.a.23101},

issn = {1552-4930 1552-4922},

year  = {2018},

date = {2018-07-01},

journal = {Cytometry. Part A : the journal of the International Society for Analytical Cytology},

volume = {93},

number = {9},

pages = {941–951},

abstract = {The identification of fibroblasts and cancer-associated fibroblasts from human cancer tissue using surface markers is difficult, especially because the markers used currently are usually not expressed solely by fibroblasts, and the identification of fibroblast-specific surface molecules is still under investigation. It was aimed to compare three commercially available antibodies in the detection of different surface epitopes of fibroblasts (anti-fibroblast, fibroblast activation protein α, and fibroblast surface protein). The specificity of their expression, employing fibroblast cell lines and tumor-derived fibroblasts from breast and prostate tissues was investigated. Both the established fibroblast cell line HFF-1 and ex vivo primary fibroblasts isolated from breast and prostate cancer tissues expressed the tested surface markers to different degrees. Surprisingly, those markers were expressed also by permanent cell lines of epithelial origin, both benign and cancer-derived (breast-cell lines MCF 10A, HMLE and prostate-cell lines BPH-1, DU 145, and PC-3). The expression of fibroblast activation protein α increased on the surface of previously described models of epithelial cells undergoing epithelial-to-mesenchymal transition in response to treatment with TGF-β1. To prove the co-expression of the fibroblast markers on cells of epithelial origin, we used freshly dissociated human prostate and breast cancer tissues. The results confirmed the co-expression of anti-fibroblast and fibroblast surface protein on CD31/CD45-negative/EpCAM-positive epithelial cells. In summary, our data support the findings that the tested fibroblast markers are not fibroblast specific and may be expressed also by cells of epithelial origin (e.g., cells undergoing EMT). Therefore, the expression of these markers should be interpreted with caution, and the combination of several epitopes for both positive (anti-fibroblast or fibroblast activation protein α) and negative (EpCAM) identification of fibroblasts from breast and prostate tumor tissues is advised. © 2017 International Society for Advancement of Cytometry.},

note = {Place: United States},

keywords = {anti-fibroblast, Biomarkers/*metabolism, Breast Neoplasms/metabolism, cancer-associated fibroblasts, Cell Line, Endopeptidases, Epithelial Cell Adhesion Molecule/metabolism, Epithelial Cells/metabolism, Epithelial-Mesenchymal Transition/*physiology, epithelial-to-mesenchymal transition, Female, fibroblast activation protein α, fibroblast surface protein, Fibroblasts/*metabolism, Gelatinases/*metabolism, Humans, Leukocyte Common Antigens/metabolism, Male, Membrane Proteins/*metabolism, PC-3 Cells, Platelet Endothelial Cell Adhesion Molecule-1/metabolism, Prostatic Neoplasms/metabolism, Serine Endopeptidases/*metabolism, Transforming Growth Factor beta1/metabolism, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{pencikova_vitro_2018,

title = {In vitro profiling of toxic effects of prominent environmental lower-chlorinated PCB congeners linked with endocrine disruption and tumor promotion.},

author = {Kateřina Pěnčíková and Lucie Svržková and Simona Strapáčová and Jiří Neča and Iveta Bartoňková and Zdeněk Dvořák and Martina Hýžďalová and Jakub Pivnička and Lenka Pálková and Hans-Joachim Lehmler and Xueshu Li and Jan Vondráček and Miroslav Machala},

doi = {10.1016/j.envpol.2018.02.067},

issn = {1873-6424 0269-7491},

year  = {2018},

date = {2018-06-01},

journal = {Environmental pollution (Barking, Essex : 1987)},

volume = {237},

pages = {473–486},

abstract = {The mechanisms contributing to toxic effects of airborne lower-chlorinated PCB congeners (LC-PCBs) remain poorly characterized. We evaluated in vitro toxicities of environmental LC-PCBs found in both indoor and outdoor air (PCB 4, 8, 11, 18, 28 and 31), and selected hydroxylated metabolites of PCB 8, 11 and 18, using reporter gene assays, as well as other functional cellular bioassays. We focused on processes linked with endocrine disruption, tumor promotion and/or regulation of transcription factors controlling metabolism of both endogenous compounds and xenobiotics. The tested LC-PCBs were found to be mostly efficient anti-androgenic (within nanomolar - micromolar range) and estrogenic (at micromolar concentrations) compounds, as well as inhibitors of gap junctional intercellular communication (GJIC) at micromolar concentrations. PCB 8, 28 and 31 were found to partially inhibit the aryl hydrocarbon receptor (AhR)-mediated activity. The tested LC-PCBs were also partial constitutive androstane receptor (CAR) and pregnane X receptor (PXR) agonists, with PCB 4, 8 and 18 being the most active compounds. They were inactive towards other nuclear receptors, such as vitamin D receptor, thyroid receptor α, glucocorticoid receptor or peroxisome proliferator-activated receptor γ. We found that only PCB 8 contributed to generation of oxidative stress, while all tested LC-PCBs induced arachidonic acid release (albeit without further modulations of arachidonic acid metabolism) in human lung epithelial cells. Importantly, estrogenic effects of hydroxylated (OH-PCB) metabolites of LC-PCBs (4-OH-PCB 8, 4-OH-PCB 11 and 4'-OH-PCB 18) were higher than those of the parent PCBs, while their other toxic effects were only slightly altered or suppressed. This suggested that metabolism may alter toxicity profiles of LC-PCBs in a receptor-specific manner. In summary, anti-androgenic and estrogenic activities, acute inhibition of GJIC and suppression of the AhR-mediated activity were found to be the most relevant modes of action of airborne LC-PCBs, although they partially affected also additional cellular targets.},

note = {Place: England},

keywords = {Air Pollutants/*toxicity, Airborne polychlorinated biphenyls, Cell Line, Constitutive Androstane Receptor, Cytoplasmic and Nuclear/metabolism, Endocrine disruption, Endocrine Disruptors/metabolism/*toxicity, Epithelial Cells/drug effects, Humans, HydroxyLated PCBs, Hydroxylation, Metabolism of xenobiotics, Neoplasms/metabolism, Polychlorinated Biphenyls/metabolism/*toxicity, Pregnane X receptor, Receptors, Signal Transduction/drug effects, Steroid/metabolism, Tumor promotion},

pubstate = {published},

tppubtype = {article}

}

@article{vargova_hypericin_2018,

title = {Hypericin affects cancer side populations via competitive inhibition of BCRP.},

author = {Jana Vargová and Jaromír Mikeš and Rastislav Jendželovský and Lucia Mikešová and Barbora Kuchárová and Ľubomír Čulka and Radek Fedr and Ján Remšík and Karel Souček and Alois Kozubík and Peter Fedoročko},

doi = {10.1016/j.biopha.2018.01.074},

issn = {1950-6007 0753-3322},

year  = {2018},

date = {2018-03-01},

journal = {Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie},

volume = {99},

pages = {511–522},

abstract = {OBJECTIVE: Cancer stem-like cells (CSLCs) are considered a root of tumorigenicity and resistance. However, their identification remains challenging. The use of the side population (SP) assay as a credible marker of CSLCs remains controversial. The SP assay relies on the elevated activity of ABC transporters that, in turn, can be modulated by hypericin (HYP), a photosensitizer and bioactive compound of St. John's Wort (Hypericum perforatum), a popular over-the-counter antidepressant. Here we aimed to comprehensively characterize the SP phenotype of cancer cells and to determine the impact of HYP on these cells. METHODS: Flow cytometry and sorting-based assays were employed, including CD24-, CD44-, CD133-, and ALDH-positivity, clonogenicity, 3D-forming ability, ABC transporter expression and activity, and intracellular accumulation of HYP/Hoechst 33342. The tumorigenic ability of SP, nonSP, and HYP-treated cells was verified by xenotransplantation into immunodeficient mice. RESULTS: The SP phenotype was associated with elevated expression of several investigated transporters and more intensive growth in non-adherent conditions but not with higher clonogenicity, tumorigenicity or ALDH-positivity. Despite stimulated BCRP level and MRP1 activity, HYP reversibly decreased the SP proportion, presumably via competitive inhibition of BCRP. HYP-selected SP cells acquired additional traits of resistance and extensively eliminated HYP. CONCLUSIONS: Our results suggest that SP is not an unequivocal CSLC-marker. However, SP could play an important role in modulating HYP-treatment and serve as a negative predictive tool for HYP-based therapies. Moreover, the use of supplements containing HYP by cancer patients should be carefully considered, due to its proposed effect on drug efflux and complex impact on tumor cells, which have not yet been sufficiently characterized.},

note = {Place: France},

keywords = {ABC transporters, Aldehyde Dehydrogenase/metabolism, Animals, Anthracenes, ATP Binding Cassette Transporter, Biomarkers, Cancer stem-like cells, Carcinogenesis/drug effects/metabolism/pathology, Cell Line, Cellular/drug effects/metabolism/pathology, Clone Cells, Drug resistance, Humans, Hypericin, Member 1/metabolism, Member 2/*metabolism, Mice, Neoplasm Proteins/*metabolism, Neoplasms/*metabolism/*pathology, Neoplastic Stem Cells/drug effects/metabolism/pathology, Perylene/*analogs & derivatives/pharmacology, Phenotype, SCID, Side population, Side-Population Cells/drug effects/*pathology, Spheroids, St. John’s wort, Subfamily B, Subfamily G, Substrate Specificity/drug effects, Survival Analysis, Tumor, Tumor/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{remsik_plasticity_2018,

title = {Plasticity and intratumoural heterogeneity of cell surface antigen expression in breast cancer.},

author = {Ján Remšík and Radek Fedr and Jiří Navrátil and Lucia Binó and Eva Slabáková and Pavel Fabian and Marek Svoboda and Karel Souček},

doi = {10.1038/bjc.2017.497},

issn = {1532-1827 0007-0920},

year  = {2018},

date = {2018-03-01},

journal = {British journal of cancer},

volume = {118},

number = {6},

pages = {813–819},

abstract = {Background:The intratumoural heterogeneity, often driven by epithelial-to-mesenchymal transition (EMT), significantly contributes to chemoresistance and disease progression in adenocarcinomas. Methods:We introduced a high-throughput screening platform to identify surface antigens that associate with epithelial–mesenchymal plasticity in well-defined pairs of epithelial cell lines and their mesenchymal counterparts. Using multicolour flow cytometry, we then analysed the expression of 10 most robustly changed antigens and identified a 10-molecule surface signature, in pan-cytokeratin-positive/EpCAM-positive and -negative fractions of dissociated breast tumours. Results:We found that surface CD9, CD29, CD49c, and integrin ß5 are lost in breast cancer cells that underwent EMT in vivo. The tetraspanin family member CD9 was concordantly downregulated both in vitro and in vivo and associated with epithelial phenotype and favourable prognosis. Conclusions:We propose that overall landscape of 10-molecule surface signature expression reflects the epithelial–mesenchymal plasticity in breast cancer.},

note = {Place: England},

keywords = {Antigens, Biomarkers, Breast Neoplasms/*genetics/*immunology/pathology, Cell Line, Cell Plasticity/immunology, Cellular Reprogramming/physiology, Epithelial-Mesenchymal Transition/immunology, Female, Flow Cytometry, Genetic, High-Throughput Screening Assays, Humans, Neoplasm Metastasis, Neoplasm/*biosynthesis/immunology, Surface/*biosynthesis/immunology, Tetraspanin 29/biosynthesis/immunology, Transcription, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{verlande_metabolic_2018,

title = {Metabolic stress regulates ERK activity by controlling KSR-RAF heterodimerization.},

author = {Amandine Verlande and Michaela Krafčíková and David Potěšil and Lukáš Trantírek and Zbyněk Zdráhal and Moustafa Elkalaf and Jan Trnka and Karel Souček and Nora Rauch and Jens Rauch and Walter Kolch and Stjepan Uldrijan},

doi = {10.15252/embr.201744524},

issn = {1469-3178 1469-221X},

year  = {2018},

date = {2018-02-01},

journal = {EMBO reports},

volume = {19},

number = {2},

pages = {320–336},

abstract = {Altered cell metabolism is a hallmark of cancer, and targeting specific metabolic nodes is considered an attractive strategy for cancer therapy. In this study, we evaluate the effects of metabolic stressors on the deregulated ERK pathway in melanoma cells bearing activating mutations of the NRAS or BRAF oncogenes. We report that metabolic stressors promote the dimerization of KSR proteins with CRAF in NRAS-mutant cells, and with oncogenic BRAF in BRAF(V600E)-mutant cells, thereby enhancing ERK pathway activation. Despite this similarity, the two genomic subtypes react differently when a higher level of metabolic stress is induced. In NRAS-mutant cells, the ERK pathway is even more stimulated, while it is strongly downregulated in BRAF(V600E)-mutant cells. We demonstrate that this is caused by the dissociation of mutant BRAF from KSR and is mediated by activated AMPK. Both types of ERK regulation nevertheless lead to cell cycle arrest. Besides studying the effects of the metabolic stressors on ERK pathway activity, we also present data suggesting that for efficient therapies of both genomic melanoma subtypes, specific metabolic targeting is necessary.},

note = {Place: England},

keywords = {*Protein Multimerization, *Stress, 14-3-3 Proteins/chemistry/metabolism, cell cycle arrest, Cell Cycle Checkpoints/genetics, Cell Line, Cell Survival, Enzyme Activation, Extracellular Signal-Regulated MAP Kinases/*metabolism, Glucose/metabolism, Glycolysis, GTP Phosphohydrolases/genetics/metabolism, Humans, Melanoma, Melanoma/genetics/metabolism, Membrane Proteins/genetics/metabolism, metabolic stress, Mutation, Oxygen Consumption, Physiological, Protein Kinases/chemistry/genetics/*metabolism, raf Kinases/chemistry/genetics/*metabolism, RAF‐ERK signaling, Recombinant Fusion Proteins, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{simeckova_multiparameter_2018,

title = {Multiparameter cytometric analysis of complex cellular response.},

author = {Šárka Šimečková and Radek Fedr and Ján Remšík and Zuzana Kahounová and Eva Slabáková and Karel Souček},

doi = {10.1002/cyto.a.23295},

issn = {1552-4930 1552-4922},

year  = {2018},

date = {2018-02-01},

journal = {Cytometry. Part A : the journal of the International Society for Analytical Cytology},

volume = {93},

number = {2},

pages = {239–248},

abstract = {Complex analysis of cellular responses after experimental treatment is important for screening, mechanistic understanding of treatment effects, and the identification of sensitive and resistant cell phenotypes. Modern multicolor flow cytometry has demonstrated its power for such analyses. Here, we introduce a multiparametric protocol for complex analysis of cytokinetics by the simultaneous detection of seven fluorescence parameters. This analysis includes the detection of two surface markers for immunophenotyping, analysis of proliferation based on the cell cycle and the measurement of incorporated nucleoside analogue 5-ethynyl-2'-deoxyuridine (EdU) in newly synthesized DNA, analysis of DNA damage using an anti-phospho-histone H2A.X (Ser139) antibody, and determination of cell death using a fixable viability probe and intracellular detection of caspase-3 activation. To demonstrate the applicability of this protocol for the analysis of heterogeneous and complex cell responses, we used different treatments and model cell lines. We demonstrated that this protocol has the potential to provide complex and simultaneous analysis of cytokinetics and analyze the heterogeneity of the response at the single-cell level. © 2017 International Society for Advancement of Cytometry.},

note = {Place: United States},

keywords = {Apoptosis, Apoptosis/*physiology, Cell Line, Cell Proliferation/*physiology, DNA Damage, DNA Damage/*physiology, Flow Cytometry, Flow Cytometry/*methods, Humans, immunophenotyping, Immunophenotyping/*methods, multiparametric analysis, proliferation, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{herudkova_chk1_2017,

title = {Chk1 Inhibitor SCH900776 Effectively Potentiates the Cytotoxic Effects of Platinum-Based Chemotherapeutic Drugs in Human Colon Cancer Cells.},

author = {Jarmila Herůdková and Kamil Paruch and Prashant Khirsariya and Karel Souček and Martin Krkoška and Olga Vondálová Blanářová and Petr Sova and Alois Kozubík and Alena Hyršlová Vaculová},

doi = {10.1016/j.neo.2017.08.002},

issn = {1476-5586 1522-8002},

year  = {2017},

date = {2017-10-01},

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

volume = {19},

number = {10},

pages = {830–841},

abstract = {Although Chk1 kinase inhibitors are currently under clinical investigation as effective cancer cell sensitizers to the cytotoxic effects of numerous chemotherapeutics, there is still a considerable uncertainty regarding their role in modulation of anticancer potential of platinum-based drugs. Here we newly demonstrate the ability of one of the most specific Chk1 inhibitors, SCH900776 (MK-8776), to enhance human colon cancer cell sensitivity to the cytotoxic effects of platinum(II) cisplatin and platinum(IV)- LA-12 complexes. The combined treatment with SCH900776 and cisplatin or LA-12 results in apparent increase in G1/S phase-related apoptosis, stimulation of mitotic slippage, and senescence of HCT116 cells. We further show that the cancer cell response to the drug combinations is significantly affected by the p21, p53, and PTEN status. In contrast to their wt counterparts, the p53- or p21-deficient cells treated with SCH900776 and cisplatin or LA-12 enter mitosis and become polyploid, and the senescence phenotype is strongly suppressed. While the cell death induced by SCH900776 and cisplatin or LA-12 is significantly delayed in the absence of p53, the anticancer action of the drug combinations is significantly accelerated in p21-deficient cells, which is associated with stimulation of apoptosis beyond G2/M cell cycle phase. We also show that cooperative killing action of the drug combinations in HCT116 cells is facilitated in the absence of PTEN. Our results indicate that SCH900776 may act as an important modulator of cytotoxic response triggered by platinum-based drugs in colon cancer cells.},

note = {Place: United States},

keywords = {Antineoplastic Agents/*pharmacology, Apoptosis/drug effects, Cell Cycle/drug effects/genetics, Cell Line, Cell Survival/drug effects, Cellular Senescence/drug effects, Checkpoint Kinase 1/*antagonists & inhibitors/genetics/*metabolism, Cisplatin/pharmacology, Colonic Neoplasms/drug therapy/genetics/*metabolism/pathology, Cyclin-Dependent Kinase Inhibitor p21/genetics/metabolism, DNA Damage/drug effects, Gene Knockout Techniques, Humans, Platinum Compounds/*pharmacology, Pyrazoles/*pharmacology, Pyrimidines/*pharmacology, Tumor, Tumor Suppressor Protein p53/genetics/metabolism},

pubstate = {published},

tppubtype = {article}

}

@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}

}

@article{hofmanova_dietary_2017,

title = {Dietary fatty acids specifically modulate phospholipid pattern in colon cells with distinct differentiation capacities.},

author = {Jiřina Hofmanová and Josef Slavík and Petra Ovesná and Zuzana Tylichová and Jan Vondráček and Nicol Straková and Alena Hyršlová Vaculová and Miroslav Ciganek and Alois Kozubík and Lucie Knopfová and Jan Šmarda and Miroslav Machala},

doi = {10.1007/s00394-016-1196-y},

issn = {1436-6215 1436-6207},

year  = {2017},

date = {2017-06-01},

journal = {European journal of nutrition},

volume = {56},

number = {4},

pages = {1493–1508},

abstract = {PURPOSE: Although beneficial effects of the dietary n-3 docosahexaenoic acid (DHA) or butyrate in colon carcinogenesis have been implicated, the mechanisms of their action are not fully clear. Here, we investigated modulations of composition of individual phospholipid (PL) classes, with a particular emphasis on cardiolipins (CLs), in colon cells treated with DHA, sodium butyrate (NaBt), or their combination (DHA/NaBt), and we evaluated possible associations between lipid changes and cell fate after fatty acid treatment. METHODS: In two distinct human colon cell models, foetal colon (FHC) and adenocarcinoma (HCT-116) cells, we compared patterns and composition of individual PL classes following the fatty acid treatment by HPLC-MS/MS. In parallel, we measured the parameters reflecting cell proliferation, differentiation and death. RESULTS: In FHC cells, NaBt induced primarily differentiation, while co-treatment with DHA shifted their response towards cell death. In contrast, NaBt induced apoptosis in HCT-116 cells, which was not further affected by DHA. DHA was incorporated in all main PL types, increasing their unsaturation, while NaBt did not additionally modulate these effects in either cell model. Nevertheless, we identified an unusually wide range of CL species to be highly increased by NaBt and particularly by DHA/NaBt, and these effects were more pronounced in HCT-116 cells. DHA and DHA/NaBt enhanced levels of high molecular weight and more unsaturated CL species, containing DHA, which was specific for either differentiation or apoptotic responses. CONCLUSIONS: We identified a wide range of CL species in the colon cells which composition was significantly modified after DHA and NaBt treatment. These specific CL modulations might contribute to distinct cellular differentiation or apoptotic responses.},

note = {Place: Germany},

keywords = {Apoptosis, Apoptosis/drug effects, Butyrate, Butyric Acid/pharmacology, Cardiolipins, Caspase 3/genetics/metabolism, Cell Differentiation/*drug effects, Cell Line, Cell Proliferation/drug effects, Colon cancer, Colon/cytology/*drug effects, Docosahexaenoic acid, Docosahexaenoic Acids/*pharmacology, HCT116 Cells, Humans, Phospholipids, Phospholipids/*chemistry, Tandem Mass Spectrometry, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{bostrom_comparative_2017,

title = {Comparative cell cycle transcriptomics reveals synchronization of developmental transcription factor networks in cancer cells.},

author = {Johan Boström and Zuzana Sramkova and Alena Salašová and Helena Johard and Diana Mahdessian and Radek Fedr and Carolyn Marks and Jiřina Medalová and Karel Souček and Emma Lundberg and Sten Linnarsson and Vítězslav Bryja and Petra Sekyrova and Mikael Altun and Michael Andäng},

doi = {10.1371/journal.pone.0188772},

issn = {1932-6203},

year  = {2017},

date = {2017-01-01},

journal = {PloS one},

volume = {12},

number = {12},

pages = {e0188772},

abstract = {The cell cycle coordinates core functions such as replication and cell division. However, cell-cycle-regulated transcription in the control of non-core functions, such as cell identity maintenance through specific transcription factors (TFs) and signalling pathways remains unclear. Here, we provide a resource consisting of mapped transcriptomes in unsynchronized HeLa and U2OS cancer cells sorted for cell cycle phase by Fucci reporter expression. We developed a novel algorithm for data analysis that enables efficient visualization and data comparisons and identified cell cycle synchronization of Notch signalling and TFs associated with development. Furthermore, the cell cycle synchronizes with the circadian clock, providing a possible link between developmental transcriptional networks and the cell cycle. In conclusion we find that cell cycle synchronized transcriptional patterns are temporally compartmentalized and more complex than previously anticipated, involving genes, which control cell identity and development.},

note = {Place: United States},

keywords = {*Transcriptome, Algorithms, Cell Cycle Proteins/genetics/metabolism, Cell Cycle/*genetics, Cell Line, Humans, Neoplasms/genetics/*metabolism/pathology, Transcription Factors/*metabolism, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{vondracek_assessment_2017,

title = {Assessment of the aryl hydrocarbon receptor-mediated activities of polycyclic aromatic hydrocarbons in a human cell-based reporter gene assay.},

author = {Jan Vondráček and Kateřina Pěnčíková and Jiří Neča and Miroslav Ciganek and Aneta Grycová and Zdeněk Dvořák and Miroslav Machala},

doi = {10.1016/j.envpol.2016.09.064},

issn = {1873-6424 0269-7491},

year  = {2017},

date = {2017-01-01},

journal = {Environmental pollution (Barking, Essex : 1987)},

volume = {220},

number = {Pt A},

pages = {307–316},

abstract = {Activation of the aryl hydrocarbon receptor (AhR)-mediated activity is one of key events in toxicity of polycyclic aromatic hydrocarbons (PAHs). Although various classes of AhR ligands may differentially activate human and rodent AhR, there is presently a lack of data on the human AhR-inducing relative potencies (REPs) of PAHs. Here, we focused on estimation of the AhR-mediated activities of a large set of environmental PAHs in human gene reporter AZ-AhR cell line, with an aim to develop the human AhR-based REP values with potential implications for risk assessment of PAHs. The previously identified weakly active PAHs mostly failed to activate the AhR in human cells. The order for REPs of individual PAHs in human cells largely corresponded with the available data from rodent-based experimental systems; nevertheless, we identified differences up to one order of magnitude in REP values of PAHs between human and rodent cells. Higher REP values were found in human cells for some important environmental contaminants or suspected carcinogens, such as indeno[1,2,3-cd]pyrene, benz[a]anthracene or benzo[b]fluoranthene, while lower REP values were determined for methyl-substituted PAHs. Our results also indicate that a different rate of metabolism for individual PAHs in human vs. rodent cells may affect estimation of REP values in human cell-based assay, and potentially alter toxicity of some compounds, such as benzofluoranthenes, in humans. We applied the AZ-AhR assay to evaluation of the AhR-mediated activity of complex mixtures of organic compounds associated with diesel exhaust particles, and we identified the polar compounds present in these mixtures as being particularly highly active in human cells, as compared with rodent cells. The present data suggest that differences may exist between the AhR-mediated potencies of PAHs in human and rodent cells, and that the AhR-mediated effects of polar PAH derivatives and metabolites in human cell models deserve further attention.},

note = {Place: England},

keywords = {AhR, AhR-mediated activity, Aryl Hydrocarbon/metabolism/*physiology, Basic Helix-Loop-Helix Transcription Factors/metabolism/*physiology, Biological Assay/methods, Carcinogens/toxicity, Cell Line, Environmental Pollutants/*toxicity, Genes, Humans, PAH mixtures, PAHs, Polycyclic Aromatic Hydrocarbons/*toxicity, Receptors, Relative effective potency, Reporter, Vehicle Emissions/toxicity},

pubstate = {published},

tppubtype = {article}

}

@article{brenerova_pure_2016,

title = {Pure non-dioxin-like PCB congeners suppress induction of AhR-dependent endpoints in rat liver cells.},

author = {Petra Brenerová and Timo Hamers and Jorke H. Kamstra and Jan Vondráček and Simona Strapáčová and Patrik L. Andersson and Miroslav Machala},

doi = {10.1007/s11356-015-4819-6},

issn = {1614-7499 0944-1344},

year  = {2016},

date = {2016-02-01},

journal = {Environmental science and pollution research international},

volume = {23},

number = {3},

pages = {2099–2107},

abstract = {The relative potencies of non-ortho-substituted coplanar polychlorinated biphenyl (PCB) congeners to activate the aryl hydrocarbon receptor (AhR) and to cause the AhR-dependent toxic events are essential for their risk assessment. Since some studies suggested that abundant non-dioxin-like PCB congeners (NDL-PCBs) may alter the AhR activation by PCB mixtures and possibly cause non-additive effects, we evaluated potential suppressive effects of NDL-PCBs on AhR activation, using a series of 24 highly purified NDL-PCBs. We investigated their impact on the model AhR agonist-induced luciferase reporter gene expression in rat hepatoma cells and on induction of CYP1A1/1B1 mRNAs and deregulation of AhR-dependent cell proliferation in rat liver epithelial cells. PCBs 128, 138, and 170 significantly suppressed AhR activation (with IC50 values from 1.4 to 5.6 μM), followed by PCBs 28, 47, 52, and 180; additionally, PCBs 122, 153, and 168 showed low but still significant potency to reduce luciferase activity. Detection of CYP1A1 mRNA levels in liver epithelial cells largely confirmed these results for the most abundant NDL-PCBs, whereas the other AhR-dependent events (CYP1B1 mRNA expression, induction of cell proliferation in confluent cells) were less sensitive to NDL-PCBs, thus indicating a more complex regulation of these endpoints. The present data suggest that some NDL-PCBs could modulate overall dioxin-like effects in complex mixtures.},

note = {Place: Germany},

keywords = {Animals, Aryl hydrocarbon receptor, Aryl Hydrocarbon/genetics/*metabolism, Cell Line, Cell Proliferation/drug effects, Cytochrome P-450 CYP1A1/genetics/metabolism, Cytochrome P450, Disruption of contact inhibition, DR-CALUX® assay, Epithelial Cells/cytology/drug effects/metabolism, Gene Expression/drug effects, Hepatocytes/cytology/drug effects/metabolism, Liver/*drug effects/metabolism, NDL-PCBs, Polychlorinated Biphenyls/*chemistry/*toxicity, Rats, Receptors, Relative effect potency, Signal Transduction/drug effects},

pubstate = {published},

tppubtype = {article}

}

@article{slabakova_opposite_2015,

title = {Opposite regulation of MDM2 and MDMX expression in acquisition of mesenchymal phenotype in benign and cancer cells.},

author = {Eva Slabáková and Gvantsa Kharaishvili and Monika Smějová and Zuzana Pernicová and Tereza Suchánková and Ján Remšík and Stanislav Lerch and Nicol Straková and Jan Bouchal and Milan Král and Zoran Culig and Alois Kozubík and Karel Souček},

doi = {10.18632/oncotarget.5392},

issn = {1949-2553},

year  = {2015},

date = {2015-11-01},

journal = {Oncotarget},

volume = {6},

number = {34},

pages = {36156–36171},

abstract = {Plasticity of cancer cells, manifested by transitions between epithelial and mesenchymal phenotypes, represents a challenging issue in the treatment of neoplasias. Both epithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET) are implicated in the processes of metastasis formation and acquisition of stem cell-like properties. Mouse double minute (MDM) 2 and MDMX are important players in cancer progression, as they act as regulators of p53, but their function in EMT and metastasis may be contradictory. Here, we show that the EMT phenotype in multiple cellular models and in clinical prostate and breast cancer samples is associated with a decrease in MDM2 and increase in MDMX expression. Modulation of EMT-accompanying changes in MDM2 expression in benign and transformed prostate epithelial cells influences their migration capacity and sensitivity to docetaxel. Analysis of putative mechanisms of MDM2 expression control demonstrates that in the context of defective p53 function, MDM2 expression is regulated by EMT-inducing transcription factors Slug and Twist. These results provide an alternative context-specific role of MDM2 in EMT, cell migration, metastasis, and therapy resistance.},

note = {Place: United States},

keywords = {Animals, Breast Neoplasms/genetics/*metabolism/pathology, Cell Cycle Proteins, Cell Line, Epithelial-Mesenchymal Transition, Epithelial-Mesenchymal Transition/*physiology, Female, Heterografts, Humans, Male, MDM2/MDMX, Mice, Nuclear Proteins/*biosynthesis, Nude, Phenotype, prostate/breast cancer, Prostatic Neoplasms/genetics/*metabolism/pathology, Proto-Oncogene Proteins c-mdm2/*biosynthesis, Proto-Oncogene Proteins/*biosynthesis, Snai2/Slug, Transfection, Tumor, TWIST},

pubstate = {published},

tppubtype = {article}

}

@article{kratochvilova_tumor_2015,

title = {Tumor suppressor candidate 3 (TUSC3) prevents the epithelial-to-mesenchymal transition and inhibits tumor growth by modulating the endoplasmic reticulum stress response in ovarian cancer cells.},

author = {Kateřina Kratochvílová and Peter Horak and Milan Ešner and Karel Souček and Dietmar Pils and Mariam Anees and Erwin Tomasich and František Dráfi and Veronika Jurtíková and Aleš Hampl and Michael Krainer and Petr Vaňhara},

doi = {10.1002/ijc.29502},

issn = {1097-0215 0020-7136},

year  = {2015},

date = {2015-09-01},

journal = {International journal of cancer},

volume = {137},

number = {6},

pages = {1330–1340},

abstract = {Ovarian cancer is one of the most common malignancies in women and contributes greatly to cancer-related deaths. Tumor suppressor candidate 3 (TUSC3) is a putative tumor suppressor gene located at chromosomal region 8p22, which is often lost in epithelial cancers. Epigenetic silencing of TUSC3 has been associated with poor prognosis, and hypermethylation of its promoter provides an independent biomarker of overall and disease-free survival in ovarian cancer patients. TUSC3 is localized to the endoplasmic reticulum in an oligosaccharyl tranferase complex responsible for the N-glycosylation of proteins. However, the precise molecular role of TUSC3 in ovarian cancer remains unclear. In this study, we establish TUSC3 as a novel ovarian cancer tumor suppressor using a xenograft mouse model and demonstrate that loss of TUSC3 alters the molecular response to endoplasmic reticulum stress and induces hallmarks of the epithelial-to-mesenchymal transition in ovarian cancer cells. In summary, we have confirmed the tumor-suppressive function of TUSC3 and identified the possible mechanism driving TUSC3-deficient ovarian cancer cells toward a malignant phenotype.},

note = {Place: United States},

keywords = {Animals, Cell Line, Endoplasmic Reticulum Stress, Endoplasmic Reticulum Stress/*genetics, Epithelial-Mesenchymal Transition/*genetics, epithelial-to-mesenchymal transition, Female, Genes, Heterografts, Humans, Inbred NOD, Membrane Proteins/*genetics, Mice, N33, ovarian cancer, Ovarian Neoplasms/*genetics, SCID, Tumor, Tumor Suppressor, Tumor Suppressor Proteins/*genetics, Tumor Suppressor/physiology, TUSC3},

pubstate = {published},

tppubtype = {article}

}

@article{svobodova_aryl_2015,

title = {The aryl hydrocarbon receptor-dependent disruption of contact inhibition in rat liver WB-F344 epithelial cells is linked with induction of survivin, but not with inhibition of apoptosis.},

author = {Jana Svobodová and Markéta Kabátková and Lenka Šmerdová and Petra Brenerová and Zdeněk Dvořák and Miroslav Machala and Jan Vondráček},

doi = {10.1016/j.tox.2015.04.001},

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

year  = {2015},

date = {2015-07-01},

journal = {Toxicology},

volume = {333},

pages = {37–44},

abstract = {Inhibition of apoptosis by the ligands of the aryl hydrocarbon receptor (AhR) has been proposed to play a role in their tumor promoting effects on liver parenchymal cells. However, little is presently known about the impact of toxic AhR ligands, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on apoptosis in other liver cell types, such as in liver epithelial/progenitor cells. In the present study, we focused on the effects of TCDD on apoptosis regulation in a model of liver progenitor cells, rat WB-F344 cell line, during the TCDD-elicited release from contact inhibition. The stimulation of cell proliferation in this cell line was associated with deregulated expression of a number of genes known to be under transcriptional control of the Hippo signaling pathway, a principal regulatory pathway involved in contact inhibition of cell proliferation. Interestingly, we found that mRNA and protein levels of survivin, a known Hippo target, which plays a role both in cell division and inhibition of apoptosis, were significantly up-regulated in rat liver epithelial cell model, as well as in undifferentiated human liver HepaRG cells. Using the short interfering RNA-mediated knockdown, we confirmed that survivin plays a central role in cell division of WB-F344 cells. When evaluating the effects of TCDD on apoptosis induction by camptothecin, a genotoxic topoisomerase I inhibitor, we observed that the pre-treatment of WB-F344 cells with TCDD increased number of cells with apoptotic nuclear morphology, and it potentiated cleavage of both caspase-3 and poly(ADP-ribose) polymerase I. This indicated that despite the observed up-regulation of survivin, apoptosis induced by the genotoxin was potentiated in the model of rat liver progenitor cells. The present results indicate that, unlike in hepatocytes, AhR agonists may not prevent induction of apoptosis elicited by DNA-damaging agents in a model of rat liver progenitor cells.},

note = {Place: Ireland},

keywords = {AhR, Animals, Apoptosis, Apoptosis/*drug effects, Aryl Hydrocarbon/*agonists/metabolism, Basic Helix-Loop-Helix Transcription Factors/*agonists/metabolism, BIRC5/survivin, Camptothecin/*toxicity, Caspase 3/metabolism, Cell Line, Contact inhibition, Contact Inhibition/*drug effects, Epithelial Cells/*drug effects/metabolism/pathology, Genetic/drug effects, Hippo signaling, Humans, Inbred F344, Inhibitor of Apoptosis Proteins/genetics/metabolism, Liver/*drug effects/metabolism/pathology, Microtubule-Associated Proteins/genetics/*metabolism, Poly (ADP-Ribose) Polymerase-1, Poly(ADP-ribose) Polymerases/metabolism, Polychlorinated Dibenzodioxins/*toxicity, Rats, Receptors, RNA Interference, Signal Transduction/drug effects, Survivin, TCDD, Time Factors, Topoisomerase I Inhibitors/*toxicity, Transcription, Transfection, Up-Regulation},

pubstate = {published},

tppubtype = {article}

}

@article{kabatkova_interactive_2015,

title = {Interactive effects of inflammatory cytokine and abundant low-molecular-weight PAHs on inhibition of gap junctional intercellular communication, disruption of cell proliferation control, and the AhR-dependent transcription.},

author = {Markéta Kabátková and Jana Svobodová and Kateřina Pěnčíková and Dilshad Shaik Mohatad and Lenka Šmerdová and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.1016/j.toxlet.2014.09.023},

issn = {1879-3169 0378-4274},

year  = {2015},

date = {2015-01-01},

journal = {Toxicology letters},

volume = {232},

number = {1},

pages = {113–121},

abstract = {Polycyclic aromatic hydrocarbons (PAHs) with lower molecular weight exhibit lesser genotoxicity and carcinogenicity than highly carcinogenic PAHs with a higher number of benzene rings. Nevertheless, they elicit specific effects linked with tumor promotion, such as acute inhibition of gap junctional intercellular communication (GJIC). Although inflammatory reaction may alter bioactivation and toxicity of carcinogenic PAHs, little is known about the impact of pro-inflammatory cytokines on toxic effects of the low-molecular-weight PAHs. Here, we investigated the impact of a pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α), on the effects associated with tumor promotion and with induction of the aryl hydrocarbon receptor (AhR)-dependent gene expression in rat liver epithelial cells. We found that a prolonged incubation with TNF-α induced a down-regulation of GJIC, associated with reduced expression of connexin 43 (Cx43), a major connexin isoform found in liver epithelial cells. The Cx43 down-regulation was partly mediated by the activity of the mitogen-activated protein (MAP) p38 kinase. Independently of GJIC modulation, or p38 activation, TNF-α potentiated the AhR-dependent proliferative effect of a model low-molecular-weight PAH, fluoranthene, on contact-inhibited cells. In contrast, this pro-inflammatory cytokine repressed the fluoranthene-induced expression of a majority of model AhR gene targets, such as Cyp1a1, Ahrr or Tiparp. The results of the present study indicate that inflammatory reaction may differentially modulate various toxic effects of low-molecular-weight PAHs; the exposure to pro-inflammatory cytokines may both strengthen (inhibition of GJIC, disruption of contact inhibition) and repress (expression of a majority of AhR-dependent genes) their impact on toxic endpoints associated with carcinogenesis.},

note = {Place: Netherlands},

keywords = {Animals, Aryl hydrocarbon receptor, Aryl Hydrocarbon/*agonists/genetics/metabolism, Basic Helix-Loop-Helix Transcription Factors/*agonists/genetics/metabolism, Cell Communication/*drug effects, Cell Line, Cell Proliferation, Cell Proliferation/*drug effects, Cell Transformation, Connexin 43/genetics/metabolism, Dose-Response Relationship, Drug, Enzyme Activation, Epithelial Cells/*drug effects/metabolism/pathology, Fluorenes/*toxicity, Gap junctions, Gap Junctions/*drug effects/metabolism/pathology, Gene Expression Regulation/drug effects, Genetic/*drug effects, Inflammation, Inflammation/chemically induced/genetics/metabolism/pathology, Liver Neoplasms/chemically induced/metabolism/pathology, Liver/*drug effects/metabolism/pathology, Molecular Weight, Neoplastic/chemically induced/metabolism/pathology, p38 Mitogen-Activated Protein Kinases/metabolism, PAHs, Rats, Receptors, Signal Transduction/drug effects, Time Factors, Transcription, Tumor Necrosis Factor-alpha/*toxicity},

pubstate = {published},

tppubtype = {article}

}

@article{ghorbanzadeh_vitro_2014,

title = {In vitro and in silico derived relative effect potencies of ah-receptor-mediated effects by PCDD/Fs and PCBs in rat, mouse, and guinea pig CALUX cell lines.},

author = {Mehdi Ghorbanzadeh and Karin I. Ede and Malin Larsson and Majorie B. M. Duursen and Lorenz Poellinger and Sandra Lücke-Johansson and Miroslav Machala and Kateřina Pěnčíková and Jan Vondráček and Martin Berg and Michael S. Denison and Tine Ringsted and Patrik L. Andersson},

doi = {10.1021/tx5001255},

issn = {1520-5010 0893-228X},

year  = {2014},

date = {2014-07-01},

journal = {Chemical research in toxicology},

volume = {27},

number = {7},

pages = {1120–1132},

abstract = {For a better understanding of species-specific relative effect potencies (REPs), responses of dioxin-like compounds (DLCs) were assessed. REPs were calculated using chemical-activated luciferase gene expression assays (CALUX) derived from guinea pig, rat, and mouse cell lines. Almost all 20 congeners tested in the rodent cell lines were partial agonists and less efficacious than 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). For this reason, REPs were calculated for each congener using concentrations at which 20% of the maximal TCDD response was reached (REP20TCDD). REP20TCDD values obtained for PCDD/Fs were comparable with their toxic equivalency factors assigned by the World Health Organization (WHO-TEF), while those for PCBs were in general lower than the WHO-TEF values. Moreover, the guinea pig cell line was the most sensitive as indicated by the 20% effect concentrations of TCDD of 1.5, 5.6, and 11.0 pM for guinea pig, rat, and mouse cells, respectively. A similar response pattern was observed using multivariate statistical analysis between the three CALUX assays and the WHO-TEFs. The mouse assay showed minor deviation due to higher relative induction potential for 2,3,7,8-tetrachlorodibenzofuran and 2,3,4,6,7,8-hexachlorodibenzofuran and lower for 1,2,3,4,6,7,8-heptachlorodibenzofuran and 3,3',4,4',5-pentachlorobiphenyl (PCB126). 2,3,7,8-Tetrachlorodibenzofuran was more than two times more potent in the mouse assay as compared with that of rat and guinea pig cells, while measured REP20TCDD for PCB126 was lower in mouse cells (0.05) as compared with that of the guinea pig (0.2) and rat (0.07). In order to provide REP20TCDD values for all WHO-TEF assigned compounds, quantitative structure-activity relationship (QSAR) models were developed. The QSAR models showed that specific electronic properties and molecular surface characteristics play important roles in the AhR-mediated response. In silico derived REP20TCDD values were generally consistent with the WHO-TEFs with a few exceptions. The QSAR models indicated that, e.g., 1,2,3,7,8-pentachlorodibenzofuran and 1,2,3,7,8,9-hexachlorodibenzofuran were more potent than given by their assigned WHO-TEF values, and the non-ortho PCB 81 was predicted, based on the guinea-pig model, to be 1 order of magnitude above its WHO-TEF value. By combining in vitro and in silico approaches, REPs were established for all WHO-TEF assigned compounds (except OCDD), which will provide future guidance in testing AhR-mediated responses of DLCs and to increase our understanding of species variation in AhR-mediated effects.},

note = {Place: United States},

keywords = {Animals, Aryl Hydrocarbon/agonists/*metabolism, Benzofurans/*pharmacology, Biological, Biological Assay, Cell Line, Computer Simulation, Dibenzofurans, Dose-Response Relationship, Drug, Guinea Pigs, Luciferases/metabolism, Mice, Models, Polychlorinated, Polychlorinated Biphenyls/*pharmacology, Polychlorinated Dibenzodioxins/*analogs & derivatives/pharmacology, Quantitative Structure-Activity Relationship, Rats, Receptors, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{pernicova_role_2014,

title = {The role of high cell density in the promotion of neuroendocrine transdifferentiation of prostate cancer cells.},

author = {Zuzana Pernicová and Eva Slabáková and Radek Fedr and Šárka Šimečková and Josef Jaroš and Tereza Suchánková and Jan Bouchal and Gvantsa Kharaishvili and Milan Král and Alois Kozubík and Karel Souček},

doi = {10.1186/1476-4598-13-113},

issn = {1476-4598},

year  = {2014},

date = {2014-05-01},

journal = {Molecular cancer},

volume = {13},

pages = {113},

abstract = {BACKGROUND: Tumor heterogeneity and the plasticity of cancer cells present challenges for effective clinical diagnosis and therapy. Such challenges are epitomized by neuroendocrine transdifferentiation (NED) and the emergence of neuroendocrine-like cancer cells in prostate tumors. This phenomenon frequently arises from androgen-depleted prostate adenocarcinoma and is associated with the development of castration-resistant prostate cancer and poor prognosis. RESULTS: In this study, we showed that NED was evoked in both androgen receptor (AR)-positive and AR-negative prostate epithelial cell lines by growing the cells to a high density. Androgen depletion and high-density cultivation were both associated with cell cycle arrest and deregulated expression of several cell cycle regulators, such as p27Kip1, members of the cyclin D protein family, and Cdk2. Dual inhibition of Cdk1 and Cdk2 using pharmacological inhibitor or RNAi led to modulation of the cell cycle and promotion of NED. We further demonstrated that the cyclic adenosine 3', 5'-monophosphate (cAMP)-mediated pathway is activated in the high-density conditions. Importantly, inhibition of cAMP signaling using a specific inhibitor of adenylate cyclase, MDL-12330A, abolished the promotion of NED by high cell density. CONCLUSIONS: Taken together, our results imply a new relationship between cell cycle attenuation and promotion of NED and suggest high cell density as a trigger for cAMP signaling that can mediate reversible NED in prostate cancer cells.},

note = {Place: England},

keywords = {*Cell Transdifferentiation/drug effects, Androgen/metabolism, Androgens/pharmacology, CDC2 Protein Kinase, Cell Count, Cell Cycle Checkpoints/drug effects, Cell Line, Cyclic AMP/metabolism, Cyclin-Dependent Kinase 2/metabolism, Cyclin-Dependent Kinases/metabolism, Epithelial Cells/drug effects/enzymology/pathology, Humans, Immunohistochemistry, Male, Neuroendocrine Cells/drug effects/*pathology, Prostatic Neoplasms/*pathology, Protein Kinase Inhibitors/pharmacology, Receptors, Signal Transduction/drug effects, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{jirik_blind_2014,

title = {Blind deconvolution in dynamic contrast-enhanced MRI and ultrasound.},

author = {Radovan Jiřík and Karel Souček and Martin Mézl and Michal Bartoš and Eva Dražanová and František Dráfi and Lucie Grossová and Jiří Kratochvíla and Ondřej Macíček and Kim Nylund and Aleš Hampl and Odd Helge Gilja and Torfinn Taxt and Zenon Jr Starčuk},

doi = {10.1109/EMBC.2014.6944569},

issn = {2694-0604 2375-7477},

year  = {2014},

date = {2014-01-01},

journal = {Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference},

volume = {2014},

pages = {4276–4279},

abstract = {This paper is focused on quantitative perfusion analysis using MRI and ultrasound. In both MRI and ultrasound, most approaches allow estimation of rate constants (Ktrans, kep for MRI) and indices (AUC, TTP) that are only related to the physiological perfusion parameters of a tissue (e.g. blood flow, vessel permeability) but do not allow their absolute quantification. Recent methods for quantification of these physiological perfusion parameters are shortly reviewed. The main problem of these methods is estimation of the arterial input function (AIF). This paper summarizes and extends the current blind-deconvolution approaches to AIF estimation. The feasibility of these methods is shown on a small preclinical study using both MRI and ultrasound.},

note = {Place: United States},

keywords = {Animals, Cell Line, Contrast Media/*pharmacokinetics, Experimental/diagnostic imaging/metabolism, Gadolinium DTPA/*pharmacokinetics, Humans, Inbred BALB C, Magnetic Resonance Imaging/methods, Mice, Neoplasm Transplantation, Neoplasms, Tissue Distribution, Tumor, Ultrasonography},

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{prochazkova_aryl_2013,

title = {Aryl hydrocarbon receptor negatively regulates expression of the plakoglobin gene (jup).},

author = {Jiřina Procházková and Markéta Kabátková and Lenka Šmerdová and Jiří Pacherník and Dominika Sykorová and Jiří Kohoutek and Pavlína Šimečková and Eva Hrubá and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.1093/toxsci/kft110},

issn = {1096-0929},

year  = {2013},

date = {2013-08-01},

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

volume = {134},

number = {2},

pages = {258–270},

abstract = {Plakoglobin is an important component of intercellular junctions, including both desmosomes and adherens junctions, which is known as a tumor suppressor. Although mutations in the plakoglobin gene (Jup) and/or changes in its protein levels have been observed in various disease states, including cancer progression or cardiovascular defects, the information about endogenous or exogenous stimuli orchestrating Jup expression is limited. Here we show that the aryl hydrocarbon receptor (AhR) may regulate Jup expression in a cell-specific manner. We observed a significant suppressive effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a model toxic exogenous activator of the AhR signaling, on Jup expression in a variety of experimental models derived from rodent tissues, including contact-inhibited rat liver progenitor cells (where TCDD induces cell proliferation), rat and mouse hepatoma cell models (where TCDD inhibits cell cycle progression), cardiac cells derived from the mouse embryonic stem cells, or cardiomyocytes isolated from neonatal rat hearts. The small interfering RNA (siRNA)-mediated knockdown of AhR confirmed its role in both basal and TCDD-deregulated Jup expression. The analysis of genomic DNA located textasciitilde2.5kb upstream of rat Jup gene revealed a presence of evolutionarily conserved AhR binding motifs, which were confirmed upon their cloning into luciferase reporter construct. The siRNA-mediated knockdown of Jup expression affected both proliferation and attachment of liver progenitor cells. The present data indicate that the AhR may contribute to negative regulation of Jup gene expression in rodent cellular models, which may affect cell adherence and proliferation.},

note = {Place: United States},

keywords = {Animals, Aryl hydrocarbon receptor, Aryl Hydrocarbon/*physiology, Base Sequence, cardiomyocytes., Cell Adhesion, Cell Line, Cell Proliferation, Cloning, desmosomes, dioxin, DNA Primers, Down-Regulation, gamma Catenin/*genetics, Gene Expression Regulation/*physiology, Genetic, Inbred F344, liver progenitor cells, Molecular, plakoglobin, Polychlorinated Dibenzodioxins/pharmacology, Promoter Regions, Rats, Real-Time Polymerase Chain Reaction, Receptors},

pubstate = {published},

tppubtype = {article}

}

@article{fedr_automatic_2013,

title = {Automatic cell cloning assay for determining the clonogenic capacity of cancer and cancer stem-like cells.},

author = {Radek Fedr and Zuzana Pernicová and Eva Slabáková and Nicol Straková and Jan Bouchal and Michal Grepl and Alois Kozubík and Karel Souček},

doi = {10.1002/cyto.a.22273},

issn = {1552-4930 1552-4922},

year  = {2013},

date = {2013-05-01},

journal = {Cytometry. Part A : the journal of the International Society for Analytical Cytology},

volume = {83},

number = {5},

pages = {472–482},

abstract = {The clonogenic assay is a well-established in vitro method for testing the survival and proliferative capability of cells. It can be used to determine the cytotoxic effects of various treatments including chemotherapeutics and ionizing radiation. However, this approach can also characterize cells with different phenotypes and biological properties, such as stem cells or cancer stem cells. In this study, we implemented a faster and more precise method for assessing the cloning efficiency of cancer stem-like cells that were characterized and separated using a high-speed cell sorter. Cell plating onto a microplate using an automatic cell deposition unit was performed in a single-cell or dilution rank mode by the fluorescence-activated cell sorting method. We tested the new automatic cell-cloning assay (ACCA) on selected cancer cell lines and compared it with the manual approach. The obtained results were also compared with the results of the limiting dilution assay for different cell lines. We applied the ACCA to analyze the cloning capacity of different subpopulations of prostate and colon cancer cells based on the expression of the characteristic markers of stem (CD44 and CD133) and cancer stem cells (TROP-2, CD49f, and CD44). Our results revealed that the novel ACCA is a straightforward approach for determining the clonogenic capacity of cancer stem-like cells identified in both cell lines and patient samples.},

note = {Place: United States},

keywords = {*Cell Proliferation, AC133 Antigen, Antigens, Biomarkers, CD/metabolism, Cell Adhesion Molecules/metabolism, Cell Line, Cell Survival, Colonic Neoplasms/metabolism/*pathology, Flow Cytometry/*methods, Glycoproteins/metabolism, Humans, Hyaluronan Receptors/metabolism, In Vitro Techniques, Integrin alpha6/metabolism, Male, Neoplasm/metabolism, Neoplastic Stem Cells/metabolism/*pathology, Peptides/metabolism, Prostatic Neoplasms/metabolism/*pathology, Tumor, Tumor Stem Cell Assay/*methods, Tumor/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{faust_ahr-mediated_2013,

title = {AhR-mediated changes in global gene expression in rat liver progenitor cells.},

author = {Dagmar Faust and Jan Vondráček and Pavel Krčmář and Lenka Smerdová and Jiřina Procházková and Eva Hrubá and Petra Hulinková and Bernd Kaina and Cornelia Dietrich and Miroslav Machala},

doi = {10.1007/s00204-012-0979-z},

issn = {1432-0738 0340-5761},

year  = {2013},

date = {2013-04-01},

journal = {Archives of toxicology},

volume = {87},

number = {4},

pages = {681–698},

abstract = {Although the tumor-promoting effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), coplanar polychlorinated biphenyls (PCBs), and related compounds in liver tissue are primarily attributed to the activation of the aryl hydrocarbon receptor (AhR), the underlying molecular mechanisms are still unclear. Liver progenitor (oval) cells have been suggested to constitute a potential target for hepatocarcinogenic chemicals. To better understand AhR-driven pathways, we analyzed the transcriptional program in response to coplanar PCB 126 in contact-inhibited rat liver progenitor WB-F344 cells using high-density microarrays. After 6-h treatment, we identified 145 significantly deregulated genes considered to be direct AhR-dependent target genes. The number of differentially regulated genes increased to 658 and 968 genes after 24 and 72 h, respectively. Gene ontology analysis revealed that these genes were primarily involved in drug and lipid metabolism, cell cycle and growth control, cancer developmental processes, cell-cell communication, and adhesion. Interestingly, the Wnt and TGF-β signaling pathways, both being involved in developmental and tumorigenic processes, belonged to the most affected pathways. AhR- and ARNT-dependent regulation of selected target genes of interest was then confirmed using TCDD as a model AhR agonist, together with pharmacological inhibition of the AhR and by RNA-interference techniques. We demonstrated AhR-dependent regulation of emerging and novel AhR target genes, such as Fst, Areg, Hbegf, Ctgf, Btg2, and Foxq1. Among them, the transcription factor Foxq1, recently suggested to contribute to tumor promotion and/or progression, was found to be regulated at both mRNA and protein levels by AhR/ARNT activation.},

note = {Place: Germany},

keywords = {Animals, Aryl Hydrocarbon/*genetics/metabolism, Cell Line, Epithelial Cells/drug effects/*metabolism/pathology, Estrogen Antagonists/toxicity, Gene Expression Regulation/drug effects/*genetics, Gene Knockdown Techniques, Liver/drug effects/*metabolism/pathology, Oligonucleotide Array Sequence Analysis, Polychlorinated Biphenyls/toxicity, Rats, Receptors, Stem Cells/drug effects/*metabolism/pathology},

pubstate = {published},

tppubtype = {article}

}

@article{andrysik_aryl_2013,

title = {Aryl hydrocarbon receptor-mediated disruption of contact inhibition is associated with connexin43 downregulation and inhibition of gap junctional intercellular communication.},

author = {Zdeněk Andrysík and Jiřina Procházková and Markéta Kabátková and Lenka Umannová and Pavlína Simečková and Jiří Kohoutek and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.1007/s00204-012-0963-7},

issn = {1432-0738 0340-5761},

year  = {2013},

date = {2013-03-01},

journal = {Archives of toxicology},

volume = {87},

number = {3},

pages = {491–503},

abstract = {The aryl hydrocarbon receptor (AhR) contributes to the control of cell-to-cell communication, cell adhesion, migration or proliferation. In the present study, we investigated the regulation of connexin43 (Cx43) and Cx43-mediated gap junctional intercellular communication (GJIC) during the AhR-dependent disruption of contact inhibition in non-tumorigenic liver epithelial cells. The contact inhibition of cell proliferation is a process restricting the cell division of confluent non-transformed cells, which is frequently abolished in cancer cells; however, the mechanisms contributing to its disruption are still only partially understood. Disruption of contact inhibition, which was induced by toxic AhR ligands 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or polycyclic aromatic hydrocarbons in epithelial WB-F344 cells, reduced Cx43 protein levels, possibly via enhanced proteasomal degradation, significantly decreased the amount of gap junction plaques and downregulated GJIC, in an AhR-dependent manner. Although both intracellular and membrane Cx43 pools were markedly reduced in cells released from contact inhibition by TCDD, siRNA-mediated Cx43 knock-down was not sufficient to stimulate proliferation in contact-inhibited cells. Our data suggest that downregulation of Cx43/GJIC in non-transformed epithelial cells is an inherent part of disruption of contact inhibition, which occurs at the post-transcriptional level. This process runs in parallel with alterations of other forms of cell-to-cell communication, thus suggesting that toxic AhR agonists may simultaneously abrogate contact inhibition and reduce GJIC, two essential mechanisms linked to deregulation of cell-to-cell communication during tumor promotion and progression.},

note = {Place: Germany},

keywords = {Animals, Aryl Hydrocarbon/*agonists/genetics/metabolism, Benz(a)Anthracenes/toxicity, Carcinogens/*toxicity, Cell Communication/*drug effects, Cell Line, Cell Proliferation, Cell Transformation, Connexin 43/genetics/*metabolism, Contact Inhibition/*drug effects, Dose-Response Relationship, Down-Regulation, Drug, Epithelial Cells/*drug effects/metabolism/pathology, Fluorenes/toxicity, Gap Junctions/*drug effects/metabolism/pathology, Gene Knockdown Techniques, Indoles/pharmacology, Ligands, Liver Neoplasms/chemically induced/metabolism/pathology, Liver/*drug effects/metabolism/pathology, Neoplastic/chemically induced/metabolism/pathology, Phloroglucinol/analogs & derivatives/pharmacology, Phosphorylation, Polychlorinated Dibenzodioxins/toxicity, Proteasome Endopeptidase Complex/metabolism, Rats, Receptors, RNA Interference, Signal Transduction/*drug effects, Time Factors, Transfection},

pubstate = {published},

tppubtype = {article}

}

@article{knopfova_c-myb_2012,

title = {c-Myb regulates matrix metalloproteinases 1/9, and cathepsin D: implications for matrix-dependent breast cancer cell invasion and metastasis.},

author = {Lucia Knopfová and Petr Beneš and Lucie Pekarčíková and Markéta Hermanová and Michal Masařík and Zuzana Pernicová and Karel Souček and Jan Smarda},

doi = {10.1186/1476-4598-11-15},

issn = {1476-4598},

year  = {2012},

date = {2012-03-01},

journal = {Molecular cancer},

volume = {11},

pages = {15},

abstract = {BACKGROUND: The c-Myb transcription factor is essential for the maintenance of stem-progenitor cells in bone marrow, colon epithelia, and neurogenic niches. c-Myb malfunction contributes to several types of malignancies including breast cancer. However, the function of c-Myb in the metastatic spread of breast tumors remains unexplored. In this study, we report a novel role of c-Myb in the control of specific proteases that regulate the matrix-dependent invasion of breast cancer cells. RESULTS: Ectopically expressed c-Myb enhanced migration and ability of human MDA-MB-231 and mouse 4T1 mammary cancer cells to invade Matrigel but not the collagen I matrix in vitro. c-Myb strongly increased the expression/activity of cathepsin D and matrix metalloproteinase (MMP) 9 and significantly downregulated MMP1. The gene coding for cathepsin D was suggested as the c-Myb-responsive gene and downstream effector of the migration-promoting function of c-Myb. Finally, we demonstrated that c-Myb delayed the growth of mammary tumors in BALB/c mice and affected the metastatic potential of breast cancer cells in an organ-specific manner. CONCLUSIONS: This study identified c-Myb as a matrix-dependent regulator of invasive behavior of breast cancer cells.},

note = {Place: England},

keywords = {Animals, Breast Neoplasms/genetics/*metabolism, Cathepsin D/genetics/*metabolism, Cell Line, Cell Movement/genetics/physiology, Electrophoresis, Female, Humans, Immunoblotting, Inbred BALB C, Matrix Metalloproteinase 1/genetics/*metabolism, Matrix Metalloproteinase 9/genetics/*metabolism, Mice, Neoplasm Metastasis/genetics/physiopathology, Polyacrylamide Gel, Proto-Oncogene Proteins c-myb/genetics/*metabolism, Real-Time Polymerase Chain Reaction, RNA, Small Interfering, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{valovicova_genotoxicity_2012,

title = {Genotoxicity of 7H-dibenzo[c,g]carbazole and its methyl derivatives in human keratinocytes.},

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

doi = {10.1016/j.mrgentox.2011.12.030},

issn = {0027-5107},

year  = {2012},

date = {2012-03-01},

journal = {Mutation research},

volume = {743},

number = {1-2},

pages = {91–98},

abstract = {Differences between tissues in the expression of drug-metabolizing enzymes may substantially contribute to tissue-specificity of chemical carcinogens. To verify this hypothesis, the spontaneously immortalized human keratinocytes HaCaT were used, in order to evaluate the genotoxic potential of 7H-dibenzo[c,g]carbazole (DBC), a known hepatocarcinogen and sarcomagen, and its synthetic tissue-specific derivatives, 5,9-dimethyl-DBC (DiMeDBC) and N-methyl-DBC (N-MeDBC), which manifest specific tropism to the liver and skin, respectively. HaCaT cells mainly express cytochrome P4501A1 (CYP1A1), which is involved in metabolism of DBC and N-MeDBC, but not DiMeDBC [10]. Both DBC and the sarcomagen N-MeDBC induced significant levels of DNA strand-breaks, micronuclei, and DNA adducts followed by the phosphorylation of the p53 protein and histone H2AX in HaCaT cells. In contrast, the specific hepatocarcinogen DiMeDBC was devoid of any significant genotoxic activity in this cell line. Our study demonstrates that the absence of drug-metabolizing enzyme(s) involved in DiMeDBC metabolism may contribute substantially to the tissue-specific genotoxicity of this hepatocarcinogen.},

note = {Place: Netherlands},

keywords = {Carbazoles/chemistry/*toxicity, Carcinogens/*toxicity, Cell Line, Cytochrome P-450 CYP1A1/metabolism, DNA Breaks, Humans, Keratinocytes/*drug effects/metabolism, Mutagenicity Tests, Mutagens/*toxicity, Organ Specificity, Single-Stranded},

pubstate = {published},

tppubtype = {article}

}

@article{hruba_gene_2011,

title = {Gene expression changes in human prostate carcinoma cells exposed to genotoxic and nongenotoxic aryl hydrocarbon receptor ligands.},

author = {Eva Hrubá and Jan Vondráček and Helena Líbalová and Jan Topinka and Vítězslav Bryja and Karel Souček and Miroslav Machala},

doi = {10.1016/j.toxlet.2011.07.011},

issn = {1879-3169 0378-4274},

year  = {2011},

date = {2011-10-01},

journal = {Toxicology letters},

volume = {206},

number = {2},

pages = {178–188},

abstract = {Carcinogenic polycyclic aromatic hydrocarbons (PAHs) are known as efficient mutagens and ligands of the aryl hydrocarbon receptor (AhR), which has been suggested to play an important role in prostate carcinogenesis. In order to evaluate the complex relationship between the genotoxicity and the AhR-mediated activity of PAHs in prostate cells, we selected benzo[a]pyrene (BaP) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), as model genotoxic and nongenotoxic AhR ligands, respectively, to explore global changes in gene expression in LNCaP cells by microarray analysis. We identified 112 genes that were differentially expressed in cells treated for 24h with BaP, TCDD or both compounds. Our data indicated that the impacts of BaP and TCDD on transcriptome of LNCaP cells significantly overlap, since over 64% of significantly up-regulated genes and 47% of down-regulated genes were similarly affected by both AhR ligands. This suggested that the activation of AhR played a prominent role in the nongenotoxic effects of BaP in the prostate carcinoma cell model LNCaP. Both AhR ligands suppressed expression of genes associated with cell cycle progression, DNA replication, spindle assembly checkpoint or DNA repair, which probably occurred secondary to inhibition of cell cycle progression. In contrast, we identified Wnt5a, an important regulator of prostate cancer progression, to be induced as early as 6h after exposure to both AhR ligands. The AhR ligand-induced Wnt5a upregulation, together with other observed alterations of gene expression, may further contribute to enhanced cell plasticity of prostate carcinoma cells.},

note = {Place: Netherlands},

keywords = {Aryl Hydrocarbon/*agonists, Benzo(a)pyrene/*toxicity, Carcinogens, Carcinoma/metabolism, Cell Cycle/drug effects, Cell Line, DNA Repair/drug effects, DNA Replication/drug effects, Environmental/*toxicity, Gene Expression Profiling, Gene Expression Regulation, Humans, Ligands, Male, Mutagens/*toxicity, Neoplastic/*drug effects, Oligonucleotide Array Sequence Analysis, Polychlorinated Dibenzodioxins/*toxicity, Prostatic Neoplasms/*metabolism, Proto-Oncogene Proteins/genetics/metabolism, Receptors, Spindle Apparatus/drug effects, Time Factors, Tumor, Wnt Proteins/genetics/metabolism, Wnt-5a Protein},

pubstate = {published},

tppubtype = {article}

}

@article{umannova_benzopyrene_2011,

title = {Benzo[a]pyrene and tumor necrosis factor-α coordinately increase genotoxic damage and the production of proinflammatory mediators in alveolar epithelial type II cells.},

author = {Lenka Umannová and Miroslav Machala and Jan Topinka and Jana Schmuczerová and Pavel Krčmář and Jiří Neča and Klára Šujanová and Alois Kozubík and Jan Vondráček},

doi = {10.1016/j.toxlet.2011.06.029},

issn = {1879-3169 0378-4274},

year  = {2011},

date = {2011-10-01},

journal = {Toxicology letters},

volume = {206},

number = {2},

pages = {121–129},

abstract = {Alveolar type II epithelial (AEII) cells regulate lung inflammatory response and, simultaneously, they are a target of environmental carcinogenic factors. We employed an in vitro model of rat AEII cells, the RLE-6TN cell line, in order to analyze the interactive effects of tumor necrosis factor-α (TNF-α), a cytokine which plays a key role in the initiation of inflammatory responses in the lung, and benzo[a]pyrene (BaP), a highly carcinogenic polycyclic aromatic hydrocarbon. TNF-α strongly augmented the formation of stable BaP diol epoxide-DNA adducts in AEII cells, which was associated with enhanced p53-Ser15 phosphorylation and decreased cell survival. The increased genotoxicity of BaP was associated with altered expression of cytochrome P450 (CYP) enzymes involved in its bioactivation, a simultaneous suppression of CYP1A1 and enhancement of CYP1B1 expression. Importantly, BaP and TNF-α acted synergistically to upregulate key inflammatory regulators in AEII cells, including the expression of inducible NO synthase and cyclooxygenase-2 (COX-2), and enhanced prostaglandin E2 production and expression of proinflammatory cytokines, such as TNF-α, interleukin-1β and interleukin-6. We observed that BaP and TNF-α together strongly activated p38 kinase, a principal regulator of inflammatory response. SB202190, a specific p38 inhibitor, prevented induction of both COX-2 and proinflammatory cytokines, thus confirming that p38 activity was crucial for the observed inflammatory reaction. Taken together, our data demonstrated, for the first time, that a proinflammatory cytokine and an environmental PAH may interact to potentiate both DNA damage and the inflammatory response in AEII cells, which may occur through coordinated upregulation of p38 activity.},

note = {Place: Netherlands},

keywords = {Alveolar Epithelial Cells/*drug effects/immunology/*metabolism, Animals, Apoptosis/drug effects, Aryl Hydrocarbon Hydroxylases/genetics/metabolism, Benzo(a)pyrene/metabolism/*toxicity, Carcinogens, Cell Line, Cell Proliferation/drug effects, Cytochrome P-450 CYP1A1/genetics/metabolism, Cytochrome P-450 CYP1B1, DNA Adducts/*metabolism, Environmental/toxicity, Enzyme Activation/drug effects, Gene Expression Regulation/drug effects, Inflammation Mediators/*metabolism, Messenger/metabolism, Mutagens/*toxicity, p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors/metabolism, Phosphorylation/drug effects, Post-Translational/drug effects, Protein Kinase Inhibitors/pharmacology, Protein Processing, Rats, RNA, Tumor Necrosis Factor-alpha/*metabolism, Tumor Suppressor Protein p53/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{andrysik_activation_2011,

title = {Activation of the aryl hydrocarbon receptor is the major toxic mode of action of an organic extract of a reference urban dust particulate matter mixture: the role of polycyclic aromatic hydrocarbons.},

author = {Zdeněk Andrysík and Jan Vondráček and Soňa Marvanová and Miroslav Ciganek and Jiří Neča and Kateřina Pěnčíková and Brinda Mahadevan and Jan Topinka and William M. Baird and Alois Kozubík and Miroslav Machala},

doi = {10.1016/j.mrfmmm.2011.06.011},

issn = {0027-5107},

year  = {2011},

date = {2011-09-01},

journal = {Mutation research},

volume = {714},

number = {1-2},

pages = {53–62},

abstract = {Many of the toxic and carcinogenic effects of urban air pollution have been linked to polycyclic aromatic hydrocarbons (PAHs) adsorbed to airborne particulate matter (PM). The carcinogenic properties of PAHs in complex organic mixtures derived from PM have been chiefly attributed to their mutagenicity. Nevertheless, PAHs are also potent activators of the aryl hydrocarbon receptor (AhR), which may contribute to their nongenotoxic effects, including tumor promotion. As the genotoxicity of carcinogenic PAHs in complex mixtures derived from urban PM is often inhibited by other mixture constituents, the AhR-mediated activity of urban PM extracts might significantly contribute to the carcinogenic activity of such mixtures. In the present study, we used an organic extract of the urban dust standard reference material, SRM1649a, as a model mixture to study a range of toxic effects related to DNA damage and AhR activation. Both the organic extract and its neutral aromatic fraction formed a low number of DNA adducts per nucleotide in the liver epithelial WB-F344 cells model, without inducing DNA damage response, such as tumor suppressor p53 activation and apoptosis. In contrast, we found that this extract, as well as its neutral and polar fractions, were potent inducers of a range of AhR-mediated responses, including induction of the AhR-mediated transcription, such as cytochrome P450 1A1/1B1 expression, and the AhR-dependent cell proliferation. Importantly, these toxic events occurred at doses one order of magnitude lower than DNA damage. The AhR-mediated activity of the neutral fraction was linked to PAHs and their derivatives, as polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls were only minor contributors to the overall AhR-mediated activity. Taken together, our data suggest that more attention should be paid to the AhR-dependent nongenotoxic events elicited by urban PM constituents, especially PAHs and their derivatives.},

note = {Place: Netherlands},

keywords = {Animals, Apoptosis/drug effects, Aryl Hydrocarbon/*metabolism, Cell Line, Cell Proliferation/drug effects, Cytochrome P-450 CYP1A1/metabolism, DNA Adducts/drug effects, DNA Damage/*drug effects, Dose-Response Relationship, Drug, Genes, Liver/drug effects, Mutagens/*toxicity, Organic Chemicals/*toxicity, p53/drug effects, Particulate Matter/*toxicity, Polycyclic Aromatic Hydrocarbons/*toxicity, Rats, Receptors},

pubstate = {published},

tppubtype = {article}

}

@article{slabakova_tgf-1-induced_2011,

title = {TGF-β1-induced EMT of non-transformed prostate hyperplasia cells is characterized by early induction of SNAI2/Slug.},

author = {Eva Slabáková and Zuzana Pernicová and Eva Slavíčková and Andrea Staršíchová and Alois Kozubík and Karel Souček},

doi = {10.1002/pros.21350},

issn = {1097-0045 0270-4137},

year  = {2011},

date = {2011-09-01},

journal = {The Prostate},

volume = {71},

number = {12},

pages = {1332–1343},

abstract = {BACKGROUND: Epithelial-mesenchymal transition (EMT) underlying cancer cell invasion and metastasis has been thoroughly studied in prostate cancer. Although EMT markers have been clinically observed in benign prostate hyperplasia, molecular events underlying the onset and progression of EMT in benign prostate cells have not been described. METHODS: EMT in BPH-1 cells was induced by TGF-β1 treatment and the kinetics of expression of EMT markers, regulators, and selected miRNAs was assessed by western blotting and quantitative RT-PCR. RESULTS: EMT in BPH-1 cells was accompanied by rapid up-regulation of SNAI2/Slug and ZEB1 transcription factors, while changes in expression levels of ZEB2 and miR-200 family members were observed after extended time intervals. Invasive phenotype with EMT hallmarks, characterizing tumorigenic clones derived from BPH-1 cells, was associated with increased mRNA levels of SNAI2, ZEB1, and ZEB2, but was not associated with significant changes in basal levels of miR-200 family members. RNA interference revealed that SNAI2/Slug is crucial for TGF-β1-induced vimentin up-regulation and migration of BPH-1 cells. CONCLUSIONS: This study suggests that in BPH-1 cells the transcription factor SNAI2/Slug is important for EMT initiation, while the ZEB family of transcription factors in cooperation with the miR-200 family may oppose the reversal of the EMT phenotype.},

note = {Place: United States},

keywords = {*Epithelial-Mesenchymal Transition/genetics, Biomarkers/metabolism, Cell Line, Cell Movement, Homeodomain Proteins/genetics, Humans, Kinetics, Male, Messenger/metabolism, MicroRNAs/metabolism, Neoplasm Invasiveness/genetics, Phenotype, Prostatic Hyperplasia/*physiopathology, Repressor Proteins/genetics, RNA, Snail Family Transcription Factors, Transcription Factors/*biosynthesis/genetics, Transforming Growth Factor beta1/*pharmacology, Up-Regulation/drug effects, Vimentin/metabolism, Zinc Finger E-box Binding Homeobox 2, Zinc Finger E-box-Binding Homeobox 1},

pubstate = {published},

tppubtype = {article}

}