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{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{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{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{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{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{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{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{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{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{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{pernicova_androgen_2011,

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

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

doi = {10.1593/neo.11182},

issn = {1476-5586 1522-8002},

year  = {2011},

date = {2011-06-01},

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

volume = {13},

number = {6},

pages = {526–536},

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

note = {Place: United States},

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

pubstate = {published},

tppubtype = {article}

}

@article{trilecova_toxic_2011,

title = {Toxic effects of methylated benzo[a]pyrenes in rat liver stem-like cells.},

author = {Lenka Trilecová and Simona Krčková and Soňa Marvanová and Kateřina Pĕnčíková and Pavel Krčmář and Jiří Neča and Petra Hulinková and Lenka Pálková and Miroslav Ciganek and Alena Milcová and Jan Topinka and Jan Vondráček and Miroslav Machala},

doi = {10.1021/tx200049x},

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

year  = {2011},

date = {2011-06-01},

journal = {Chemical research in toxicology},

volume = {24},

number = {6},

pages = {866–876},

abstract = {The methylated benzo[a]pyrenes (MeBaPs) are present at significant levels in the environment, especially in the sediments contaminated by petrogenic PAHs. However, the existing data on their toxic effects in vitro and/or in vivo are still largely incomplete. Transcription factor AhR plays a key role in the metabolic activation of PAHs to genotoxic metabolites, but the AhR activation may also contribute to the tumor promoting effects of PAHs. In this study, the AhR-mediated activity of five selected MeBaP isomers was estimated in the DR-CALUX reporter gene assay performed in rat hepatoma cells. Detection of other effects, including induction of CYP1A1, CYP1B1, and AKR1C9 mRNAs, DNA adduct formation, production of reactive oxygen species, oxidation of deoxyguanosine, and cell cycle modulation and apoptosis, was performed in the rat liver epithelial WB-F344 cell line, a model of liver progenitor cells. We identified 1-MeBaP as the most potent inducer of AhR activation, stable DNA adduct formation, checkpoint kinase 1 and p53 phosphorylation, and apoptosis. These effects suggest that 1-MeBaP is a potent genotoxin eliciting a typical sequence of events ascribed to carcinogenic PAHs: induction of CYP1 enzymes, formation of high levels of DNA adducts, activation of DNA damage responses (including p53 phosphorylation), and cell death. In contrast, 10-MeBaP, representing BaP isomers substituted with the methyl group in the angular ring, elicited only low levels DNA adduct formation and apoptosis. Other MeBaPs under study also elicited strong apoptotic responses associated with DNA adduct formation as the prevalent mode of toxic action of these compounds in liver cells. MeBaPs induced a weak production of ROS, which did not lead to significant oxidative DNA damage. Importantly, 1-MeBaP and 3-MeBaP were found to be potent AhR agonists, one order of magnitude more potent than BaP, thus suggesting that the AhR-dependent modulations of gene expression, deregulation of cell survival mechanisms, and further nongenotoxic effects associated with AhR activation may further contribute to their tumor promotion and carcinogenicity.},

note = {Place: United States},

keywords = {Animals, Apoptosis/drug effects, Aryl Hydrocarbon/*metabolism, Benzo(a)pyrene/*chemistry/*toxicity, Cell Cycle/drug effects, Cell Line, Checkpoint Kinase 1, DNA Adducts/metabolism, Epithelial Cells/drug effects/metabolism, Gene Expression Regulation/drug effects, Liver/*cytology, Methylation, Mutagens/*chemistry/*toxicity, Oxidative Stress/drug effects, Protein Kinases/metabolism, Rats, Receptors, Stem Cells/drug effects/metabolism, Tumor, Tumor Suppressor Protein p53/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{benes_inhibition_2011,

title = {Inhibition of topoisomerase IIα: novel function of wedelolactone.},

author = {Petr Benes and Lucia Knopfova and Filip Trcka and Alice Nemajerova and Diana Pinheiro and Karel Soucek and Miroslav Fojta and Jan Smarda},

doi = {10.1016/j.canlet.2011.01.002},

issn = {1872-7980 0304-3835},

year  = {2011},

date = {2011-04-01},

journal = {Cancer letters},

volume = {303},

number = {1},

pages = {29–38},

abstract = {The naturally occurring coumestan wedelolactone has been previously shown to reduce growth of various cancer cells. So far, the growth-suppressing effect of wedelolactone has been attributed to the inhibition of the NFκB transcription factor and/or androgen receptors. We found that wedelolactone suppressed growth and induced apoptosis of androgen receptor-negative MDA-MB-231 breast cancer cells at concentrations that did not inhibit the NFκB activity. The cells responded to wedelolactone by the S and G2/M phase cell cycle arrest and induction of the DNA damage signaling. Wedelolactone interacted with dsDNA and inhibited the activity of DNA topoisomerase IIα. We conclude that wedelolactone can act as growth suppressor independently of NFκB and androgen receptors.},

note = {Place: Ireland},

keywords = {Antigens, Antineoplastic Agents/pharmacology, Apoptosis/drug effects, Breast Neoplasms/*drug therapy/enzymology/pathology, Cell Cycle/drug effects, Cell Growth Processes/drug effects, Cell Line, Cell Survival/drug effects, Coumarins/*pharmacology, DNA Damage, DNA Topoisomerases, DNA-Binding Proteins/*antagonists & inhibitors/metabolism, Enzyme-Linked Immunosorbent Assay, Female, Humans, Immunoblotting, Neoplasm/metabolism, Signal Transduction, Topoisomerase Inhibitors/*pharmacology, Tumor, Type II/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{vondalova_blanarova_cisplatin_2011,

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

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

doi = {10.1093/carcin/bgq220},

issn = {1460-2180 0143-3334},

year  = {2011},

date = {2011-01-01},

journal = {Carcinogenesis},

volume = {32},

number = {1},

pages = {42–51},

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

note = {Place: England},

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

pubstate = {published},

tppubtype = {article}

}

@article{hruba_genotoxic_2010,

title = {Genotoxic polycyclic aromatic hydrocarbons fail to induce the p53-dependent DNA damage response, apoptosis or cell-cycle arrest in human prostate carcinoma LNCaP cells.},

author = {Eva Hrubá and Lenka Trilecová and Sona Marvanová and Pavel Krcmár and Lenka Vykopalová and Alena Milcová and Helena Líbalová and Jan Topinka and Andrea Starsíchová and Karel Soucek and Jan Vondrácek and Miroslav Machala},

doi = {10.1016/j.toxlet.2010.06.004},

issn = {1879-3169 0378-4274},

year  = {2010},

date = {2010-09-01},

journal = {Toxicology letters},

volume = {197},

number = {3},

pages = {227–235},

abstract = {Exposure to polycyclic aromatic hydrocarbons (PAHs) has been positively associated with prostate cancer, but knowledge of the formation of PAH-DNA adducts and related genotoxic events in prostatic cells is limited. In the present study, benzo[a]pyrene (BaP), a potent mutagenic PAH, formed significant levels of DNA adducts in cell lines derived from human prostate carcinoma. When analyzing the effect of BaP on the induction of CYP1 enzymes participating in the metabolic activation of PAHs in LNCaP cells, we found that BaP induced expression of CYP1A1 and CYP1A2, but not CYP1B1 enzyme. Despite a significant amount of DNA adducts being formed by BaP and, to a lesser extent also by another strong genotoxin, dibenzo[a,l]pyrene, neither apoptosis nor cell-cycle arrest were induced in LNCaP cells. LNCaP cells were not sensitized to the induction of apoptosis by PAHs even through inhibition of the phosphoinositide-3-kinase/Akt pro-survival pathway. The lack of apoptosis was not due a disruption of expression of pro-apoptotic and pro-survival members of the Bcl-2 family of apoptosis regulators. In contrast to other genotoxic stimuli, genotoxic PAHs failed to induce DNA double-strand breaks, as illustrated by the lack of phosphorylation of histone H2AX or checkpoint kinase-2. BaP did not activate p53, as evidenced by the lack of p53 accumulation, phosphorylation at Ser15, or induction of p53 transcriptional targets. Taken together, although genotoxic PAHs produced significant levels of DNA adducts in a model of human prostate carcinoma cells, they did not activate the mechanisms leading to elimination of cells with significant damage to DNA, presumably due to their failure to activate the p53-dependent DNA damage response.},

note = {Place: Netherlands},

keywords = {Animals, Apoptosis/*drug effects, Carcinoma/*metabolism, Cell Line, DNA Damage/*drug effects, Environmental Pollutants/toxicity, Gene Expression Regulation, Male, Neoplastic/drug effects, Polycyclic Aromatic Hydrocarbons/*toxicity, Prostatic Neoplasms/*metabolism, Tumor, Tumor Suppressor Protein p53/*metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{vanhara_growthdifferentiation_2009,

title = {Growth/differentiation factor-15 inhibits differentiation into osteoclasts–a novel factor involved in control of osteoclast differentiation.},

author = {Petr Vanhara and Eva Lincová and Alois Kozubík and Pierre Jurdic and Karel Soucek and Jan Smarda},

doi = {10.1016/j.diff.2009.07.008},

issn = {1432-0436 0301-4681},

year  = {2009},

date = {2009-11-01},

journal = {Differentiation; research in biological diversity},

volume = {78},

number = {4},

pages = {213–222},

abstract = {Survival and capability of cancer cells to form metastases fundamentally depend on interactions with their microenvironment. Secondary tumors originating from prostate carcinomas affect remodeling of bone tissue and can induce both osteolytic and osteocondensing lesions. However, particular molecular mechanisms responsible for selective homing and activity of cancer cells in bone microenvironment have not been clarified yet. Growth/differentiation factor-15 (GDF-15), a distant member of the TGF-beta protein family, has recently been associated with many human cancers, including prostate. We show that both pure GDF-15 and the GDF-15-containing growth medium of 1,25(OH)(2)-vitamin D(3)-treated prostate adenocarcinoma LNCaP cells suppress formation of mature osteoclasts differentiated from RAW264.7 macrophages and bone-marrow precursors by M-CSF/RANKL in a dose-dependent manner. GDF-15 inhibits expression of c-Fos and activity of NFkappaB by delayed degradation of IkappaB. Moreover, GDF-15 inhibits expression of carbonic anhydrase II and cathepsin K, key osteoclast enzymes, and induces changes in SMAD and p38 signaling. The lack of functional osteoclasts can contribute to accumulation of bone matrix by reduction of bone resorption. These results unveil new role of GDF-15 in modulation of osteoclast differentiation and possibly in therapy of bone metastases.},

note = {Place: England},

keywords = {Acid Phosphatase/metabolism, Animals, Calcitriol/pharmacology, Carbonic Anhydrase II/antagonists & inhibitors, Cathepsin K/antagonists & inhibitors/genetics, Cell Differentiation/*drug effects, Cell Line, Conditioned/pharmacology, Culture Media, Dose-Response Relationship, Drug, Femur/cytology, Growth Differentiation Factor 15/*pharmacology, Humans, Inbred Strains, Isoenzymes/metabolism, Macrophage Colony-Stimulating Factor/pharmacology, Macrophages/cytology, Male, Mice, NF-kappa B/antagonists & inhibitors, Osteoclasts/*drug effects/metabolism, Prostatic Neoplasms/metabolism, Proto-Oncogene Proteins c-fos/antagonists & inhibitors, RANK Ligand/pharmacology, Tartrate-Resistant Acid Phosphatase, Time Factors, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{lincova_multiple_2009,

title = {Multiple defects in negative regulation of the PKB/Akt pathway sensitise human cancer cells to the antiproliferative effect of non-steroidal anti-inflammatory drugs.},

author = {Eva Lincová and Ales Hampl and Zuzana Pernicová and Andrea Starsíchová and Pavel Krcmár and Miroslav Machala and Alois Kozubík and Karel Soucek},

doi = {10.1016/j.bcp.2009.05.001},

issn = {1873-2968 0006-2952},

year  = {2009},

date = {2009-09-01},

journal = {Biochemical pharmacology},

volume = {78},

number = {6},

pages = {561–572},

abstract = {Antitumorigenic effects of non-steroidal anti-inflammatory drugs (NSAIDs) are well established in several types of cancer disease. However, the mechanisms driving these processes are not understood in all details. In our study, we observed significant differences in sensitivity of cancer epithelial cell lines to COX-independent antiproliferative effects of NSAIDs. The prostate cancer cell line LNCaP, lacking both critical enzymes in the negative control of PKB/Akt activation, PTEN and SHIP2, was the most sensitive to these effects, as assessed by analysing the cell cycle profile and expression of cell cycle regulating proteins. We found that p53 protein and its signalling pathway is not involved in early antiproliferative action of the selected NSAID-indomethacin. RNAi provided evidence for the involvement of p21(Cip1/Waf1), but not GDF-15, in antiproliferative effects of indomethacin in LNCaP cells. Interestingly, we also found that indomethacin activated PKB/Akt and induced nuclear localisation of p21(Cip1/Waf1) and Akt2 isoform. Our results are in agreement with other studies and suggest that maintaining of the p21(Cip1/Waf1) level and its intracellular localisation might be influenced by Akt2. Knock-down of SHIP2 by RNAi in PTEN negative prostate and colon cancer cell lines resulted in higher sensitivity to antiproliferative effects of indomethacin. Our data suggest novel mechanisms of NSAIDs antiproliferative action in cancer epithelial cells, which depends on the status of negative regulation of the PKB/Akt pathway and the isoform-specific action of Akt2. Thus, unexpectedly, multiple defects in negative regulation of the PKB/Akt pathway may contribute to increased sensitivity to chemopreventive effects of these widely used drugs.},

note = {Place: England},

keywords = {Anti-Inflammatory Agents, Antineoplastic Agents/pharmacology, Cell Cycle Proteins/metabolism, Cell Cycle/*drug effects/physiology, Cell Line, Cyclin-Dependent Kinase Inhibitor p21/*biosynthesis, Enzyme Induction, Epithelial Cells/*drug effects/pathology, Extracellular Signal-Regulated MAP Kinases/metabolism, Gene Expression/drug effects, Growth Differentiation Factor 15/biosynthesis, Humans, Indomethacin/pharmacology, Male, Non-Steroidal/*pharmacology, Phosphatidylinositol 3-Kinases, Prostatic Neoplasms/*pathology, Proto-Oncogene Proteins c-akt/*metabolism, RNA Interference, Signal Transduction/drug effects/physiology, Tumor, Tumor Suppressor Protein p53/genetics/*metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{takacova_role_2009,

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

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

doi = {10.1042/BJ20080952},

issn = {1470-8728 0264-6021},

year  = {2009},

date = {2009-04-01},

journal = {The Biochemical journal},

volume = {419},

number = {2},

pages = {419–425},

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

note = {Place: England},

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

pubstate = {published},

tppubtype = {article}

}

@article{ondrouskova_heavy_2009,

title = {Heavy metals induce phosphorylation of the Bcl-2 protein by Jun N-terminal kinase.},

author = {Eva Ondrousková and Jana Slovácková and Vendula Pelková and Jirina Procházková and Karel Soucek and Petr Benes and Jan Smarda},

doi = {10.1515/BC.2009.007},

issn = {1431-6730},

year  = {2009},

date = {2009-01-01},

journal = {Biological chemistry},

volume = {390},

number = {1},

pages = {49–58},

abstract = {The Bcl-2 protein is one of the key components of biochemical pathways controlling programmed cell death. The function of this protein can be regulated by posttranslational modifications. Phosphorylation of Bcl-2 has been considered to be significantly associated with cell cycle arrest in the G2/M phase of the cell cycle, and with cell death caused by defects of microtubule dynamics. This study shows that phosphorylation of Bcl-2 can be induced by heavy metals due to activation of the Jun N-terminal kinase pathway that is not linked to the G2/M cell cycle arrest. Furthermore, we demonstrate that hyperphosphorylated Bcl-2 protein is a more potent inhibitor of zinc-induced cell death than its hypophosphorylated mutant form. These data suggest that regulation of Bcl-2 protein function by phosphorylation is an important part of cell responses to stress.},

note = {Place: Germany},

keywords = {Animals, Apoptosis/drug effects, Cell Line, Electrophoresis, Gene Expression Regulation, Heavy/*pharmacology, Humans, JNK Mitogen-Activated Protein Kinases/*metabolism, Metals, Neoplastic/drug effects, Phosphorylation/drug effects, Physiological/drug effects, Post-Translational/drug effects, Protein Processing, Proto-Oncogene Proteins c-bcl-2/*metabolism, Signal Transduction/drug effects, Stress, Tumor, Zinc/pharmacology},

pubstate = {published},

tppubtype = {article}

}

@article{gavelova_reduction_2008,

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

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

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

issn = {0009-2797},

year  = {2008},

date = {2008-10-01},

journal = {Chemico-biological interactions},

volume = {176},

number = {1},

pages = {9–18},

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

note = {Place: Ireland},

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

pubstate = {published},

tppubtype = {article}

}

@article{marvanova_toxic_2008,

title = {Toxic effects of methylated benz[a]anthracenes in liver cells.},

author = {Sona Marvanová and Jan Vondrácek and Katerrina Penccíková and Lenka Trilecová and Pavel Krcmárr and Jan Topinka and Zuzana Nováková and Alena Milcová and Miroslav Machala},

doi = {10.1021/tx700305x},

issn = {0893-228X},

year  = {2008},

date = {2008-02-01},

journal = {Chemical research in toxicology},

volume = {21},

number = {2},

pages = {503–512},

abstract = {Monomethylated benz[ a]anthracenes (MeBaAs) are an important group of methylated derivatives of polycyclic aromatic hydrocarbons (PAHs). Although the methyl substitution reportedly affects their mutagenicity and tumor-initiating activity, little is known about the impact of methylation on the effects associated with activation of the aryl hydrocarbon receptor (AhR)-dependent gene expression and/or toxic events associated with tumor promotion. In the present study, we studied the effects of a series of MeBaAs on the above-mentioned end points in rat liver cell lines and compared them with the effects of benz[ a]anthracene (BaA) and the potent carcinogen 7,12-dimethylbenz[ a]anthracene (DMBA). Methyl substitution enhanced the AhR-mediated activity of BaA derivatives determined in a reporter gene assay, as the induction equivalency factors (IEFs) of all MeBaAs were higher than that of BaA. IEFs of 6-MeBaA and 9-MeBaA, two of the most potent MeBaAs, were more than two orders of magnitude higher than the IEF of BaA. Correspondingly, all MeBaAs induced higher levels of cytochrome P450 1A1 mRNA. Both BaA and MeBaAs had similar effects on the expression of cytochrome P450 1B1 or aldo-keto reductase 1C9 in rat liver epithelial WB-F344 cells. In contrast to genotoxic DMBA, MeBaAs induced low DNA adduct formation. Only 10-MeBaA induced apoptosis and accumulation of phosphorylated p53, which could be associated with the induction of oxidative stress, similar to DMBA. With the exception of 10-MeBaA, all MeBaAs induced cell proliferation in contact-inhibited WB-F344 cells, which corresponded with their ability to activate AhR. 1-, 2-, 8-, 10-, 11-, and 12-MeBaA inhibited gap junctional intercellular communication (GJIC) in WB-F344 cells. This mode of action, like disruption of cell proliferation control, might contribute to tumor promotion. Taken together, these data showed that the methyl substitution significantly influences those effects of MeBaAs associated with AhR activation or GJIC inhibition.},

note = {Place: United States},

keywords = {10-Dimethyl-1, 2-benzanthracene/chemistry/metabolism/toxicity, 9, Animals, Apoptosis/drug effects, Benz(a)Anthracenes/chemistry/metabolism/*toxicity, Carcinoma, Cell Line, Cell Proliferation/drug effects, Cytochrome P-450 Enzyme System/genetics/metabolism, DNA Adducts/analysis/metabolism, DNA/drug effects/metabolism, Dose-Response Relationship, Drug, Enzyme Induction, Enzymologic/drug effects, Gap Junctions/drug effects, Gene Expression Regulation, Genes, Hepatocellular, Hepatocytes/*drug effects/metabolism/pathology, Inbred F344, Liver Neoplasms, Messenger/metabolism, Methylation, Rats, Reporter/drug effects, RNA, Stem Cells/*drug effects/metabolism/pathology, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{vondracek_concentrations_2007,

title = {Concentrations of methylated naphthalenes, anthracenes, and phenanthrenes occurring in Czech river sediments and their effects on toxic events associated with carcinogenesis in rat liver cell lines.},

author = {Jan Vondrácek and Lenka Svihálková-Sindlerová and Katerina Pencíková and Sona Marvanová and Pavel Krcmár and Miroslav Ciganek and Jirí Neca and James E. Trosko and Brad Upham and Alois Kozubík and Miroslav Machala},

doi = {10.1897/07-161R.1},

issn = {0730-7268},

year  = {2007},

date = {2007-11-01},

journal = {Environmental toxicology and chemistry},

volume = {26},

number = {11},

pages = {2308–2316},

abstract = {Alkylated polycyclic aromatic hydrocarbons (PAHs) are important environmental pollutants. In the present study, we determined levels of monomethylated naphthalenes (MeNap), phenanthrenes (MePhe), and anthracenes (MeAnt) in Czech river sediments. The levels of MePhe generally were lower than the concentrations of phenanthrene. In contrast, both MeNap and MeAnt were found at levels higher than their respective parent compounds in the majority of sampling sites. We then investigated their aryl hydrocarbon receptor (AhR)-mediated activity, accumulation of phosphorylated p53 protein, induction of expression of cytochrome P450 1A1 (CYP1A1), inhibition of gap junctional intercellular communication (GJIC), and effects on cell proliferation in rat liver cell models to evaluate the relative importance of these toxicity mechanisms of low-molecular-weight methylated PAHs. Methylated phenanthrene and anthracene compounds were weak inducers of AhR-mediated activity as determined both in a reporter gene assay system and by detection of the endogenous gene (Cyp1a1) induction. 2-Methylphenanthrene was the most potent AhR ligand. Contribution of MeAnt and MePhe to overall AhR-inducing potencies should be taken into account in PAH-contaminated environments. Nevertheless, their effects on AhR were not sufficient to modulate cell proliferation in a normal rat liver progenitor cell model system. These PAHs only had a marginal effect on p53 phosphorylation at high doses of 1-, 3-, and 9-MePhe as well as 1 MeAnt. On the other hand, both 2- and 9-MeAnt as well as all the MePhe under study were efficient inhibitors of GJIC, suggesting that these compounds might act as tumor promoters. In summary, inhibition of GJIC and partial activation of AhR seem to be the most prominent toxic effects of the methylated PAHs in the present study.},

note = {Place: United States},

keywords = {Animals, Anthracenes/toxicity, Aryl Hydrocarbon/metabolism, Carcinogens/*toxicity, Cell Line, Cell Proliferation/*drug effects, Cytochrome P-450 CYP1A1/genetics/metabolism, Czech Republic, Dose-Response Relationship, Drug, Environmental Pollutants/*toxicity, Gap Junctions/*drug effects/metabolism, Gene Expression Regulation/*drug effects/physiology, Geologic Sediments/*chemistry, Liver/cytology/pathology, Methylation, Naphthalenes/toxicity, Phenanthrenes/toxicity, Rats, Receptors, Rivers/*chemistry, Tumor, Tumor Suppressor Protein p53/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{horvath_different_2007,

title = {Different cell cycle modulation following treatment of human ovarian carcinoma cells with a new platinum(IV) complex vs cisplatin.},

author = {Viktor Horváth and Karel Soucek and Lenka Svihálková-Sindlerová and Jan Vondrácek and Olga Blanárová and Jirina Hofmanová and Petr Sova and Alois Kozubík},

doi = {10.1007/s10637-007-9062-7},

issn = {0167-6997},

year  = {2007},

date = {2007-10-01},

journal = {Investigational new drugs},

volume = {25},

number = {5},

pages = {435–443},

abstract = {Platinum (IV) derivative with adamantylamine-LA-12-represents a new generation of highly efficient anti-cancer drug derived from cisplatin and is currently in the final stage of phase I clinical trials. Understanding the specific mechanisms of its effects on cell cycle is necessary for defining the mode of action of LA-12. In this study, we characterized the ability of LA-12 to induce cell cycle perturbations in ovarian cancer cell line A2780 as compared to equitoxic cisplatin treatment. LA-12 induced a permanent accumulation of A2780 cells in S phase while cisplatin caused G2/M arrest at 24-h time point, where we also detected an increased expression of Gadd45alpha protein. Although both derivatives induced a rapid increase of p53 expression, this was not associated with a down-regulation of Mdm2 protein. Increased expression of p21(Cip1/WAF1) protein and its association with cyclins A and B1 suggested that this cyclin-dependent kinase inhibitor might contribute significantly to the observed perturbations of cell cycle. The results of this study provide insight into the mechanism of action of platinum-based derivative with adamantylamine on cell cycle in ovarian cancer cells. The differences between effects of LA-12 and cisplatin suggest that more attention should be paid to elucidation of modes of action of novel platinum(IV) complexes at cellular level.},

note = {Place: United States},

keywords = {Amantadine/*analogs & derivatives/pharmacology, Antineoplastic Agents/*pharmacology, bcl-2-Associated X Protein/metabolism, Carcinoma/drug therapy/metabolism, Cell Cycle Proteins/metabolism, Cell Cycle/*drug effects, Cell Line, Cell Proliferation/drug effects, Cisplatin/*pharmacology, Female, Humans, Organoplatinum Compounds/*pharmacology, Ovarian Neoplasms/drug therapy/metabolism, Proto-Oncogene Proteins c-mdm2/metabolism, Tumor, Tumor Suppressor Protein p53/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{horvath_platinumiv_2006,

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

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

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

issn = {0090-8258},

year  = {2006},

date = {2006-07-01},

journal = {Gynecologic oncology},

volume = {102},

number = {1},

pages = {32–40},

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

note = {Place: United States},

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

pubstate = {published},

tppubtype = {article}

}

@article{soucek_normal_2006,

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

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

doi = {10.1002/pros.20416},

issn = {0270-4137},

year  = {2006},

date = {2006-06-01},

journal = {The Prostate},

volume = {66},

number = {9},

pages = {954–965},

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

note = {Place: United States},

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

pubstate = {published},

tppubtype = {article}

}

@article{stika_mk-886_2006,

title = {MK-886 enhances tumour necrosis factor-alpha-induced differentiation and apoptosis.},

author = {Jirí Stika and Jan Vondrácek and Jirina Hofmanová and Vladimír Simek and Alois Kozubík},

doi = {10.1016/j.canlet.2005.06.012},

issn = {0304-3835},

year  = {2006},

date = {2006-06-01},

journal = {Cancer letters},

volume = {237},

number = {2},

pages = {263–271},

abstract = {We investigated the role of the 5-lipoxygenase (5-LOX) pathway of arachidonic acid metabolism in tumour necrosis factor-alpha (TNF-alpha)-induced differentiation of human leukemic HL-60 cells using MK-886, an inhibitor of 5-LOX activating protein. MK-886 augmented cell cycle arrest and differentiation induced by TNF-alpha; however, both effects were probably 5-LOX-independent, because a general LOX inhibitor, NDGA, had no effect. Apoptosis was significantly elevated after combined TNF-alpha and MK-886 treatment, which could be partially associated with changes of Mcl-1 protein expression. NF-kappaB signalling or activation of JNKs were not modulated by MK-886. Thus, in addition to apoptosis, MK-886 can enhance TNF-alpha-induced differentiation.},

note = {Place: Ireland},

keywords = {*Apoptosis, Arachidonate 5-Lipoxygenase/metabolism, Cell Cycle, Cell Differentiation, Cell Line, Cell Survival, HL-60 Cells, Humans, Indoles/*pharmacology, Lipoxygenase Inhibitors/*pharmacology, Signal Transduction, Time Factors, Tumor, Tumor Necrosis Factor-alpha/*metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{pliskova_effects_2005,

title = {Effects of silymarin flavonolignans and synthetic silybin derivatives on estrogen and aryl hydrocarbon receptor activation.},

author = {Martina Plísková and Jan Vondrácek and Vladimír Kren and Radek Gazák and Petr Sedmera and Daniela Walterová and Jitka Psotová and Vilím Simánek and Miroslav Machala},

doi = {10.1016/j.tox.2005.06.020},

issn = {0300-483X},

year  = {2005},

date = {2005-11-01},

journal = {Toxicology},

volume = {215},

number = {1-2},

pages = {80–89},

abstract = {Silymarin, a standardized mixture of flavonolignans, or its major constituents could be effective for prevention and treatment of hepatic damage or skin cancer. However, their potential side effects, such as modulation of endocrine functions via the disruption of estrogen receptor (ER) and/or aryl hydrocarbon receptor (AhR) activation, are largely unknown. In the present study, we investigated impact of silymarin, its constituents and a series of their synthetic derivatives on ER- and AhR-mediated activities using in vitro reporter gene assays. We found that none of the compounds under study affected the AhR-mediated activity in rat hepatoma cells. Contrary to that, several compounds behaved as either partial or full ER agonists. Silymarin elicited partial ER activation, with silybin B being probably responsible for a majority of the weak ER-mediated activity of silymarin; silybin A and other flavonolignans were found to be inactive and potent ER agonist taxifolin is only a minor constituent of silymarin. To our knowledge, this is probably the first time, when receptor-specific in vitro effects of separated diastereomers have been demonstrated. In contrast to silymarin constituents, the synthetic silybin derivatives, potentially useful as chemoprotective agents, did not modulate the ER-mediated activity, with exception of 23-O-pivaloylsilybin. Interestingly, 7-O-benzylsilybin potentiated ER-mediated activity of 17beta-estradiol despite possessing no estrogenic activity. In conclusion, our data suggest that estrogenicity of some silymarin constituents should be taken in account as their potential side effect when considered as chemopreventive compounds. These results also stress the need to study biological activities of purified or synthesized diastereomers of silybin derivatives.},

note = {Place: Ireland},

keywords = {Animals, Aryl Hydrocarbon/*metabolism, Cell Line, Cell Survival/drug effects, Dose-Response Relationship, Drug, Estrogen/*metabolism, Humans, Luciferases/biosynthesis/genetics, Molecular Structure, Rats, Receptors, Silybin, Silymarin/chemistry/pharmacology, Stereoisomerism, Tumor},

pubstate = {published},

tppubtype = {article}

}

@article{kozubik_high_2005,

title = {High effectiveness of platinum(IV) complex with adamantylamine in overcoming resistance to cisplatin and suppressing proliferation of ovarian cancer cells in vitro.},

author = {Alois Kozubík and Viktor Horváth and Lenka Svihálková-Sindlerová and Karel Soucek and Jirina Hofmanová and Petr Sova and Ales Kroutil and Frantisek Zák and Adolf Mistr and Jaroslav Turánek},

doi = {10.1016/j.bcp.2004.09.005},

issn = {0006-2952},

year  = {2005},

date = {2005-02-01},

journal = {Biochemical pharmacology},

volume = {69},

number = {3},

pages = {373–383},

abstract = {[(OC-6-43)-bis(acetato)(1-adamantylamine)amminedichloroplatinum(IV)], coded as LA-12, is an octahedral platinum(IV) complex containing a bulky hydrophobic ligand - adamantylamine. The use of bulky hydrophobic amines as non-leaving ligands, may increase uptake of the compound by the cancer cells. Therefore, the effects of LA-12 on sensitive (A2780) and cisplatin resistant (A2780cis) ovarian cancer cell lines were investigated and compared to those of cisplatin. IC(50) and IC(90) concentrations of LA-12 were 6- (A2780) or 18-fold (A2780cis) lower than those for cisplatin (MTT assay). Equitoxic concentrations (IC(50) or IC(90)) of both compounds caused a significant and similar time- and dose-dependent inhibition of cell proliferation and an increase in the number of floating cells which corresponded to the decrease of total cell viability. A different type and dynamics of cell cycle perturbation after cisplatin and LA-12 treatment were detected. Exposure to LA-12 resulted in transient accumulation of A2780 and A2780cis cells in S phase, while cisplatin caused G(2)/M arrest in sensitive and S phase arrest in resistant cells. A relatively low rate of apoptosis after exposure to IC(50) or IC(90) of both complexes was observed, markedly higher in resistant A2780cis cells. Western blot analysis indicated a concentration-dependent p53 level increase in both lines (higher after cisplatin treatment). PARP cleavage was observed only in A2780cis cells. In conclusion, LA-12 was found to be significantly more efficient than cisplatin, and it was able to overcome the acquired cisplatin resistance (showing resistance factor 2.84-fold lower than those for cisplatin). In spite of the low rate of apoptosis, LA-12 caused increase of p53 level and cell cycle perturbations in the ovarian cancer cell lines studied.},

note = {Place: England},

keywords = {Amantadine/*analogs & derivatives/*pharmacology, Antineoplastic Agents/*pharmacology, Cell Cycle/drug effects, Cell Line, Cell Proliferation/drug effects, Cisplatin/*pharmacology, DNA Fragmentation/drug effects, Drug resistance, Female, Humans, Neoplasm, Organoplatinum Compounds/*pharmacology, Ovarian Neoplasms/*drug therapy/pathology, Poly(ADP-ribose) Polymerases/analysis, Tumor, Tumor Suppressor Protein p53/analysis},

pubstate = {published},

tppubtype = {article}

}