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1.
PLoS One ; 12(6): e0179065, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28617818

RESUMO

Endothelial cells represent major effectors in inflammation and angiogenesis, processes that drive a multitude of pathological states such as atherosclerosis and cancer. Both inflammation and angiogenesis are interconnected with each other in the sense that many pro-inflammatory proteins possess proangiogenic properties and vice versa. To elucidate this interplay further, we present a comparative proteome study of inflammatory and angiogenic activated endothelial cells. HUVEC were stimulated with interleukin 1-ß and VEGF, respectively. Cultured primary cells were fractionated into secreted, cytoplasmic and nuclear protein fractions and processed for subsequent LC-MS/MS analysis. Obtained protein profiles were filtered for fraction-specific proteins to address potential cross fractional contamination, subjected to comparative computational biology analysis (GO-Term enrichment analysis, weighted gene co-expression analysis) and compared to published mRNA profiles of IL-1ß respectively VEGF stimulated HUVEC. GO Term enrichment analysis and comparative pathway analysis revealed features such as NOD and NfkB signaling for inflammatory activated HUVEC and VEGF and ErB signaling for VEGF-activated HUVEC with potential crosstalk via map kinases MAP2K2. Weighted protein co-expression network analysis revealed several potential hub genes so far not associated with driver function in inflammation or angiogenesis such as HSPG2, ANXA3, and GPI. "Classical" inflammation or angiogenesis markers such as IL6, CXCL8 or CST1 were found in a less central position within the co-expression networks. In conclusion, this study reports a framework for the computational biology based analysis of proteomics data applied to cytoplasmic, nucleic and extracellular fractions of quiescent, inflammatory and angiogenic activated HUVEC. Novel potential hub genes relevant for these processes were successfully identified.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteoma/biossíntese , Fator A de Crescimento do Endotélio Vascular/farmacologia , Perfilação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Proteômica
2.
J Exp Clin Cancer Res ; 34: 134, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26526352

RESUMO

BACKGROUND: Enhanced signalling via the epidermal growth factor receptor (EGFR) is a hallmark of multiple human carcinomas. However, in recent years data have accumulated that EGFR might also be hyperactivated in human sarcomas. Aim of this study was to investigate the influence of EGFR inhibition on cell viability and its interaction with chemotherapy response in osteosarcoma cell lines. METHODS: We have investigated a panel of human osteosarcoma cell lines regarding EGFR expression and downstream signalling. To test its potential applicability as therapeutic target, inhibition of EGFR by gefitinib was combined with osteosarcoma chemotherapeutics and cell viability, migration, and cell death assays were performed. RESULTS: Osteosarcoma cells expressed distinctly differing levels of functional EGFR reaching in some cases high amounts. Functionality of EGFR in osteosarcoma cells was proven by EGF-mediated activation of both MAPK and PI3K/AKT pathway (determined by phosphorylation of ERK1/2, AKT, S6, and GSK3ß). The EGFR-specific inhibitor gefitinib blocked EGF-mediated downstream signal activation. At standard in vitro culture conditions, clinically achievable gefitinib doses demonstrated only limited cytotoxic activity, however, significantly reduced long-term colony formation and cell migration. In contrast, under serum-starvation conditions active gefitinib doses were distinctly reduced while EGF promoted starvation survival. Importantly, gefitinib significantly supported the anti-osteosarcoma activities of doxorubicin and methotrexate regarding cell survival and migratory potential. CONCLUSION: Our data suggest that EGFR is not a major driver for osteosarcoma cell growth but contributes to starvation- and chemotherapy-induced stress survival. Consequently, combination approaches including EGFR inhibitors should be evaluated for treatment of high-grade osteosarcoma patients.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Ósseas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/metabolismo , Osteossarcoma/metabolismo , Apoptose , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Gefitinibe , Expressão Gênica , Humanos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos
3.
Mol Carcinog ; 51 Suppl 1: E176-82, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22495810

RESUMO

Human telomerase reverse transcriptase (TERT) gene encodes the catalytic subunit of telomerase and is located on chromosome 5p15, a genomic region which was found to be associated with multiple cancer types. But no associations with colorectal cancer (CRC) have been reported until recently. Therefore, the purpose of this study was to investigate the influence of seven single-nucleotide polymorphisms (SNPs) of TERT on susceptibility to colorectal polyps and CRC. The study population of our ongoing colorectal cancer study of Austria (CORSA) comprised 3,842 Caucasian participants. A total of 3,264 participants was genotyped including 142 CRC cases, 492 high-risk polyps, 837 low-risk polyps, and 1,793 polyp-free controls verified by colonoscopy. Genotyping was performed by TaqMan assay using genomic DNA. The impact of each SNP was estimated by multiple logistic regression analyses performed with R Version 2.11.1. None of the investigated TERT SNPs (rs2736122, rs2853676, rs2735940, rs2736098, rs2075786, rs2736100, rs4975605) were found to be associated with risk of CRC nor colonic polyps. However, the haplotype CGTATGG was associated with a significantly increased risk of high-risk polyps (OR = 1.48, 95% CI 1.01-2.17, P = 0.043). In accordance with other studies our results suggest no major influence of the investigated TERT SNPs on CRC and colorectal polyp risk. However, relevance of telomerase in tumorigenesis of multiple malignancies demands further investigations of the 5p15 locus concerning CRC susceptibility.


Assuntos
Pólipos do Colo/genética , Neoplasias Colorretais/genética , Polimorfismo de Nucleotídeo Único , Telomerase/genética , Idoso , Idoso de 80 Anos ou mais , Áustria , Estudos de Casos e Controles , Cromossomos Humanos Par 5 , Feminino , Frequência do Gene , Predisposição Genética para Doença , Haplótipos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , População Branca/genética
4.
J Invest Dermatol ; 131(10): 2087-95, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21753785

RESUMO

Cutaneous melanoma is a tumor with rising incidence and a very poor prognosis at the disseminated stage. Melanomas are characterized by frequent mutations in BRAF and also by overexpression of fibroblast growth factor 2 (FGF2), offering opportunities for therapeutic intervention. We investigated inhibition of FGF signaling and its combination with dacarbazine or BRAF inhibitors as an antitumor strategy in melanoma. The majority of melanoma cell lines displayed overexpression of FGF2 but also FGF5 and FGF18 together with different isoforms of FGF receptors (FGFRs) 1-4. Blockade of FGF signals with dominant-negative receptor constructs (dnFGFR1, 3, or 4) or small-molecule inhibitors (SU5402 and PD166866) reduced melanoma cell proliferation, colony formation, as well as anchorage-independent growth, and increased apoptosis. DnFGFR constructs also significantly inhibited tumor growth in vivo. Combination of FGF inhibitors with dacarbazine showed additive or antagonistic effects, whereas synergistic drug interaction was observed when combining FGFR inhibition with the multikinase/BRAF inhibitor sorafenib or the V600E mutant-specific BRAF inhibitor RG7204. In conclusion, FGFR inhibition has antitumor effects against melanoma cells in vitro and in vivo. Combination with BRAF inhibition offers a potential for synergistic antimelanoma effects and represents a promising therapeutic strategy against advanced melanoma.


Assuntos
Melanoma/terapia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Neoplasias Cutâneas/terapia , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose , Benzenossulfonatos/administração & dosagem , Linhagem Celular Tumoral , Dacarbazina/administração & dosagem , Ensaios de Seleção de Medicamentos Antitumorais , Genes Dominantes , Humanos , Indóis/administração & dosagem , Melanócitos/citologia , Melanoma/patologia , Niacinamida/análogos & derivados , Compostos de Fenilureia , Prognóstico , Piridinas/administração & dosagem , Transdução de Sinais , Neoplasias Cutâneas/patologia , Sorafenibe , Sulfonamidas/administração & dosagem , Vemurafenib
5.
Cancer Epidemiol ; 35(5): e38-41, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21612998

RESUMO

BACKGROUND: X-ray repair cross complementation group 1 (XRCC1) plays a key role in base excision repair. The purpose of this study was to examine the association of two genetic polymorphisms in XRCC1 (rs1799782 and rs25487) with risk of colorectal polyps and colorectal cancer (CRC). METHODS: In the ongoing colorectal cancer study of Austria (CORSA), a total of 3091 Caucasian participants was genotyped using 5'-nuclease TaqMan assays. Multiple logistic regression was applied to compare individuals of the control group against three different case groups namely CRC cases, high-risk and low-risk polyps. RESULTS: The two investigated SNPs in XRCC1 were not found to be associated with neither CRC risk nor polyp risk. Comparing the CRC cases versus the controls the OR was 0.60 (95%CI 0.27-1.31) for the heterozygous polymorphic genotype of SNP rs1799782 and 1.47 (95%CI 0.81-2.65) for the homozygous polymorphic genotype of SNP rs25487. Comparing the high-risk polyp group versus the controls the OR was 2.64 (95%CI 0.61-11.42) for the homozygous polymorphic genotype of SNP rs1799782 and 0.89 (95%CI 0.60-1.33) for SNP rs25487, respectively. In an haplotype analysis also no statistically significant association was found. CONCLUSION: Our finding that none of the two investigated SNPs of XRCC1 were significantly associated with risk of CRC or polyps is consistent with the results of a recently published meta-analysis.


Assuntos
Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Polimorfismo de Nucleotídeo Único/genética , Idoso , Idoso de 80 Anos ou mais , Áustria , Estudos de Casos e Controles , Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , DNA de Neoplasias/genética , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Haplótipos/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
6.
Carcinogenesis ; 32(6): 866-71, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21422235

RESUMO

Telomerase reactivation and expression of human telomerase gene [human telomerase reverse transcriptase (hTERT)] are hallmarks of unlimited proliferation potential of cancer cells. A polymorphic tandem repeats minisatellite of hTERT gene, termed MNS16A was reported to influence hTERT expression. To assess the role of MNS16A as potential biomarker for colorectal cancer (CRC), we investigated for the first time the association of MNS16A genotypes with risk of colorectal polyps and CRC. In the ongoing colorectal cancer study of Austria (CORSA), 3842 Caucasian participants were recruited within a large screening project in the province Burgenland including 90 CRC cases, 308 high-risk polyps, 1022 low-risk polyps and 1822 polyp free controls verified by colonoscopy. MNS16A genotypes were determined by polymerase chain reaction from genomic DNA. Associations of MNS16A genotypes with CRC risk were estimated by logistic regression analysis computing odds ratios (ORs) and 95% confidence intervals (CIs). We identified five different variable number of tandem repeats (VNTRs) of MNS16A including VNTR-364, a newly discovered rare variant. VNTR-274 allele was associated with a 2.7-fold significantly increased risk of CRC compared with the VNTR-302 wild-type (OR = 2.69; 95% CI = 1.11-6.50; P = 0.028). In our CORSA study, the medium length VNTR-274 was identified as risk factor for CRC. Although, this population-based study herewith reports the largest cohort size concerning MNS16A thus far, further large-scale studies in diverse populations are warranted to confirm hTERT MNS16A genotype as potential biomarker for assessment of CRC risk.


Assuntos
Neoplasias Colorretais/genética , Repetições Minissatélites/genética , Polimorfismo Genético/genética , Sequências de Repetição em Tandem/genética , Telomerase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Áustria/epidemiologia , Sequência de Bases , Pólipos do Colo , Neoplasias Colorretais/epidemiologia , DNA de Neoplasias/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco
7.
J Thorac Oncol ; 6(5): 852-63, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21358348

RESUMO

INTRODUCTION: Human malignant pleural mesothelioma (MPM) is an asbestos-related malignancy characterized by frequent resistance to chemotherapy and radiotherapy. Here, we investigated the feasibility of mammalian target of rapamycin (mTOR) inhibition by temsirolimus as an antimesothelioma strategy. METHODS: Phosphorylation of mTOR (p-mTOR) was assessed by immunohistochemistry in MPM surgical specimens (n = 70). Activation of mTOR and impact of mTOR inhibition by temsirolimus was determined in MPM cell lines in vitro (n = 6) and in vivo as xenografts in severe combined immunodeficiency mice (n = 2) either as single agent or in combination with cisplatin. RESULTS: Strong immunoreactivity for p-mTOR was predominantly detected in epitheloid and biphasic but not sarcomatoid MPM specimens while adjacent normal tissues remained widely unstained. Accordingly, all mesothelioma cell lines harbored activated mTOR, which was further confirmed by hyperphosphorylation of the downstream targets pS6K, S6, and 4EBP1. Temsirolimus potently blocked mTOR-mediated signals and exerted a cytostatic effect on mesothelioma cell lines in vitro cultured both as adherent monolayers and as nonadherent spheroids. Mesothelioma cells with intrinsic or acquired cisplatin resistance exhibited hypersensitivity against temsirolimus. Accordingly, cisplatin and temsirolimus exerted synergistic inhibition of the mTOR downstream signals and enhanced growth inhibition and/or apoptosis induction in mesothelioma cell lines. Finally, temsirolimus was highly active against MPM xenograft models in severe combined immunodeficiency mice both as a single agent and in combination with cisplatin. CONCLUSION: The mTOR inhibitor temsirolimus is active against mesothelioma in vitro and in vivo and synergizes with chemotherapy. These data suggest mTOR inhibition as a promising novel therapeutic strategy against MPM.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mesotelioma/tratamento farmacológico , Neoplasias Pleurais/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cisplatino/administração & dosagem , Sinergismo Farmacológico , Estudos de Viabilidade , Feminino , Humanos , Técnicas Imunoenzimáticas , Marcação In Situ das Extremidades Cortadas , Técnicas In Vitro , Mesotelioma/metabolismo , Mesotelioma/patologia , Camundongos , Camundongos SCID , Neoplasias Pleurais/metabolismo , Neoplasias Pleurais/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Esferoides Celulares , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Exp Dermatol ; 19(12): 1040-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21087322

RESUMO

Aurora kinases represent promising novel cancer therapy targets. Genomic analyses of human cutaneous melanoma (CMM) models (N = 51, low passage) by classical and/or array CGH revealed frequent gains at chromosome 20q (65%, amplifications in 45%) repeatedly including the Aurora A gene locus. Accordingly, the majority of CMM cell cultures overexpressed Aurora A when compared to proliferating non-malignant cells. Moreover, CMM cells even when arrested in G1/S cell cycle phase contained readily detectable levels of Aurora A indicating incomplete degradation during mitosis. Already at low concentrations (10-100 nm), long-term (7-10 days) application of the pan-Aurora kinase inhibitor VE-465 completely prevented colony formation in all CMM models tested. In contrast, blockade of cell survival/proliferation and DNA synthesis as well as the induction of apoptosis by VE-465 distinctly differed in short-term experiments (up to 72 h exposure). Both cell cycle arrest and DNA synthesis blockade depended on the level of VE-465-mediated p53/p21 activation while p53/p21 unresponsiveness led to repetitive endoreduplication (>8n DNA content). In contrast, apoptosis induction by VE-465 and Aurora A siRNA did not correlate with p53/p21 responsiveness and DNA synthesis blockade. Moreover, application of the Aurora B-specific inhibitor ZM447439 and siRNA was less efficient to induce CMM cell death proofing that apoptosis induction by VE-465 depended predominantly on Aurora A targeting. In combination experiments with chemotherapeutic agents, VE-465 acted additive to antagonistic when applied concomitantly but in several cases even synergistic when applied consecutively. In summary, we suggest that the Aurora A kinase might represent a promising target of well-designed novel antimelanoma strategies.


Assuntos
Melanoma/tratamento farmacológico , Melanoma/patologia , Piperazinas/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Aurora Quinase B , Aurora Quinases , Caspase 7/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromossomos Humanos/genética , Sinergismo Farmacológico , Amplificação de Genes/genética , Células HCT116 , Humanos , Melanoma/enzimologia , Melanoma/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Poliploidia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Interferente Pequeno/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
9.
J Eval Clin Pract ; 16(6): 1309-13, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20738477

RESUMO

RATIONALE, AIMS AND OBJECTIVES: The quality of communication between health care professionals is a key issue determining health outcomes in cancer care. This study aims to find out what importance cancer patients in Austria attach to information exchange between hospital-based doctors and their general practitioners (GPs) and how patients perceive this flow of information. METHODS: In this cross-sectional study, cancer patients seeking help at a community-based organization in the voluntary sector (Viennese Cancer League) were polled with a 16-item questionnaire. Contingency tables were evaluated by means of the chi-squared and Mantel-Haenszel test. RESULTS: The mean age of the 252 respondents - 92.6% of those polled (272) - was 51.9 years (SD ± 13.6). 87.5% [female (f): 92.1%, male (m): 80.2%] considered the exchange of information between the hospital-based specialists and their GP 'very important' or 'important'; 12.5% (f: 8.0%, m: 19.8%) 'not so important' or 'not at all important'; 28.1% (f: 26.0%, m: 31.2%) of patients considered the flow of information as 'very good' or 'fairly good', but 50.9% (f: 58.7, m: 40.0%) as 'rather poor' or 'poor'. Some 34.8% of patients thought that their cancer disease was first suspected by a hospital-based specialist; 42.1% thought that it was first suspected by a doctor outside the hospital. Even when patients were counselled elsewhere they gave high importance to the provision of appropriate information to their GP. CONCLUSIONS: Cancer patients in Austria attach high importance to the provision of appropriate information to their GP by hospitals and perceive this exchange of information as insufficient, a finding that could well be prevalent in other European health systems.


Assuntos
Comunicação , Clínicos Gerais , Oncologia , Corpo Clínico Hospitalar , Pacientes/psicologia , Percepção , Adulto , Idoso , Áustria , Estudos Transversais , Atenção à Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias , Atenção Primária à Saúde
10.
Free Radic Biol Med ; 49(9): 1444-52, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20708679

RESUMO

The beneficial health effects of (-)-epigallocatechin-3-gallate (EGCG), the main catechin of green tea, have been attributed to complex interactions with a focus on antioxidative properties. Susceptibility to autoxidation and production of cytotoxic reactive oxygen species (ROS), mostly H(2)O(2), have been suggested to occur in vitro but also in vivo. In this study, we address whether autoxidation-derived H(2)O(2) may be involved in the cytoprotective effects of EGCG. To that end we investigated keratinocyte-derived HaCat and HL-60 promyelocytic leukemia cells with significantly different sensitivities to H(2)O(2) (IC(50) 117.3 versus 58.3 µM, respectively) and EGCG (134.1 versus 84.1 µM). HaCat cells significantly resisted cytotoxicity and DNA damage based on enhanced H(2)O(2) clearance, improved DNA repair, and reduced intracellular ROS generation. Cumulative versus bolus EGCG and H(2)O(2) treatment and H(2)O(2) pretreatment before subsequent high-dose EGCG and vice versa significantly reduced DNA damage and cytotoxicity in HaCat cells only. Addition of catalase abolished the protective activities of low-dose H(2)O(2) and EGCG. In summary, our data suggest that autoxidative generation of low-dose H(2)O(2) is a significant player in the cell-type-specific cytoprotection mediated by EGCG and support the hypothesis that regular green tea consumption can contribute as a pro-oxidant to increased resistance against high-dose oxidative stressors.


Assuntos
Antioxidantes/farmacologia , Catequina/análogos & derivados , Citoproteção , Queratinócitos/efeitos dos fármacos , Estresse Oxidativo , Apoptose/efeitos dos fármacos , Catalase/farmacologia , Catequina/farmacologia , Linhagem Celular , Dano ao DNA/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/metabolismo , Queratinócitos/metabolismo , Queratinócitos/patologia , Oxirredução/efeitos dos fármacos
11.
J Biol Inorg Chem ; 15(5): 737-48, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20221888

RESUMO

The ruthenium compound KP1019 has demonstrated promising anticancer activity in a pilot clinical trial. This study aims to evaluate the intracellular uptake/binding patterns of KP1019 and its sodium salt KP1339, which is currently in a phase I-IIa study. Although KP1339 tended to be moderately less cytotoxic than KP1019, IC(50) values in several cancer cell models revealed significant correlation of the cytotoxicity profiles, suggesting similar targets for the two drugs. Accordingly, both drugs activated apoptosis, indicated by caspase activation via comparable pathways. Drug uptake determined by inductively coupled plasma mass spectrometry (ICP-MS) was completed after 1 h, corresponding to full cytotoxicity as early as after 3 h of drug exposure. Surprisingly, the total cellular drug uptake did not correlate with cytotoxicity. However, distinct differences in intracellular distribution patterns suggested that the major targets for the two ruthenium drugs are cytosolic rather than nuclear. Consequently, drug-protein binding in cytosolic fractions of drug-treated cells was analyzed by native size-exclusion chromatography (SEC) coupled online with ICP-MS. Ruthenium-protein binding of KP1019- and KP1339-treated cells distinctly differed from the platinum binding pattern observed after cisplatin treatment. An adapted SEC-SEC-ICP-MS system identified large protein complexes/aggregates above 700 kDa as initial major binding partners in the cytosol, followed by ruthenium redistribution to the soluble protein weight fraction below 40 kDa. Taken together, our data indicate that KP1019 and KP1339 rapidly enter tumor cells, followed by binding to larger protein complexes/organelles. The different protein binding patterns as compared with those for cisplatin suggest specific protein targets and consequently a unique mode of action for the ruthenium drugs investigated.


Assuntos
Antineoplásicos/metabolismo , Indazóis/metabolismo , Compostos Organometálicos/metabolismo , Proteínas/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Sítios de Ligação , Proliferação de Células/efeitos dos fármacos , Citosol/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indazóis/síntese química , Indazóis/química , Indazóis/farmacologia , Espectrometria de Massas , Peso Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Ligação Proteica , Compostos de Rutênio , Relação Estrutura-Atividade , Fatores de Tempo , Células Tumorais Cultivadas
12.
Neuro Oncol ; 12(1): 28-36, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20150365

RESUMO

O(6)-Methylguanine DNA methyltransferase (MGMT) is implicated as a major predictive factor for treatment response to alkylating agents including temozolomide (TMZ) of glioblastoma multiforme (GBM) patients. However, whether the MGMT status in GBM patients should be detected at the level of promoter methylation or protein expression is still a matter of debate. Here, we compared promoter methylation (by methylation-specific polymerase chain reaction) and protein expression (by Western blot) in tumor cell explants with respect to prediction of TMZ response and survival of GBM patients (n = 71). Methylated MGMT gene promoter sequences were detected in 47 of 71 (66%) cases, whereas 37 of 71 (52%) samples were scored positive for MGMT protein expression. Although overall promoter methylation correlated significantly with protein expression (chi(2) test, P < .001), a small subgroup of samples did not follow this association. In the multivariate Cox regression model, a significant interaction between MGMT protein expression, but not promoter methylation, and TMZ therapy was observed (test for interaction, P = .015). In patients treated with TMZ (n = 42), MGMT protein expression predicted a significantly shorter overall survival (OS; hazard ratio [HR] for death 5.53, 95% confidence interval [CI] 1.76-17.37; P = .003), whereas in patients without TMZ therapy (n = 29), no differences in OS were observed (HR for death 1.00, 95% CI 0.45-2.20; P = .99). These data suggest that lack of MGMT protein expression is superior to promoter methylation as a predictive marker for TMZ response in GBM patients.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/tratamento farmacológico , Metilases de Modificação do DNA/biossíntese , Enzimas Reparadoras do DNA/biossíntese , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Proteínas Supressoras de Tumor/biossíntese , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/mortalidade , Dacarbazina/uso terapêutico , Feminino , Glioblastoma/enzimologia , Glioblastoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Temozolomida , Resultado do Tratamento , Adulto Jovem
13.
Cancer Causes Control ; 21(1): 91-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19784788

RESUMO

PURPOSE: Insulin-like growth factor 1 (IGF1) is a peptide growth factor that promotes cell proliferation and inhibits apoptosis. The bioavailability of IGF1 is regulated by the insulin-like growth factor binding protein 3 (IGFBP3). The purpose of this study was to examine the association of genetic variants in IGF1 (rs6214, rs6220, and rs35767) and IGFBP3 (rs2854744 and rs2854746) with risk of colorectal polyps and colorectal cancer. METHODS: In this ongoing colorectal cancer study of Austria (CORSA), a total of 3,360 Caucasian participants, consisting of 178 colorectal cancer patients, 328 patients with high risk polyps, 1,059 patients with low risk colorectal polyps, and 1,795 colonoscopy-negative controls, were recruited within a large colorectal screening project in the province Burgenland and from three hospitals in Vienna. Multiple logistic regression was applied to compare individuals of the control group against three different risk groups, namely, colorectal cancer group, high risk polyp group, and low risk polyp group. RESULTS: Carriers of the homozygous polymorphic genotype of the SNP rs6214 were associated with an increased colorectal risk (OR = 1.79, 95% CI 1.04-1.90) compared to the colonoscopy-negative controls; this was also found when combining colorectal cancer cases and high risk polyp group (OR = 1.39, 95% CI 1.01-1.90). CONCLUSION: Our results suggest that the SNP rs6214 of IGF1 could have an impact on developing colorectal cancer and colorectal polyps with villous elements.


Assuntos
Pólipos do Colo/genética , Neoplasias Colorretais/genética , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Polimorfismo Genético , Idoso , Idoso de 80 Anos ou mais , Pólipos do Colo/patologia , Neoplasias Colorretais/epidemiologia , Feminino , Predisposição Genética para Doença , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
14.
Mol Nutr Food Res ; 53(9): 1112-22, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19653228

RESUMO

The fusariotoxins beauvericin (BEA) and the structurally related enniatins (ENN) are frequent contaminants of grain-based food and feed. They exert potent cytotoxic activities based on apoptosis induction. Since it is known, that reactive oxygen species (ROS) and DNA damage lead to apoptotic cell death, this study aimed to clarify whether oxidative stress and DNA interactions are involved in ENN- and BEA-induced cytotoxicity. Diverse cellular and molecular assays indicated that oxidative stress does not contribute to ENN- and BEA-induced cytotoxicity. In contrast, both fusariotoxins were shown to exert moderate antioxidative activities. Moreover, only at high concentrations (>100 microM) both mycotoxins were found to intercalate substantially into dsDNA and to inhibit the catalytic activity of topoisomerase I and II. Furthermore, the potent cytotoxic activity of ENN and BEA was shown to be widely independent of cellular mismatch- and nucleotide excision repair pathways. Also the ataxia-telangiectasia mutated (ATM) protein kinase, a well known DNA damage sensor, did not affect BEAs cytotoxic potential while in ENN-induced cytotoxicity ATM had a detectable but not a major modulating influence. Together, our data suggest that ROS and DNA damage are not key factors in ENN- and BEA-mediated cytotoxicity.


Assuntos
Apoptose/efeitos dos fármacos , Dano ao DNA , Depsipeptídeos/farmacologia , Estresse Oxidativo , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Reparo do DNA , Humanos , Inibidores da Topoisomerase I , Inibidores da Topoisomerase II
15.
Mol Nutr Food Res ; 53(7): 904-20, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19517454

RESUMO

Enniatins (ENN) and beauvericin (BEA) exert cytotoxic properties. Here, we observed that their impact on Ca(2+)-homeostasis can be reversed by exogenous ATP. Thus, we investigated whether membrane-located ATP-binding cassette (ABC) transporters influence ENNs- and BEA-induced cytotoxicity. In short-term exposure assays breast cancer resistance protein (ABCG2)-overexpression weakly but significantly reduced the cytotoxic activity of BEA but not ENNs. In contrast, multidrug resistance-associated protein-1 (ABCC1)- and P-glycoprotein (ABCB1)-overexpression was not protective under identical conditions. ABCG2-mediated resistance against BEA was reversible by ABCG2 modulators. In long-term exposure assays, ABCG2 and ABCB1 significantly protected against ENNs- and to a lesser extent BEA-induced cytotoxicity. Moreover, both fusariotoxins potently inhibited the ABCG2- and ABCB1-mediated efflux of specific fluorescent substrates, with BEA being more effective. Additionally, ATPase and photoaffinity-labelling assays proofed interaction of both substances with ABCG2 and ABCB1. Remarkably, 2 years selection of KB-3-1 cells against both fusariotoxins resulted only in two-fold ENNs but negligible BEA resistance. Interestingly, the selected sublines displayed upregulation of multidrug resistance proteins and crossresistance to other chemotherapeutics. Summarizing, ABCG2 and ABCB1 slightly but significantly protect human cells against ENNs- and BEA-induced cytotoxicity. However, both mycotoxins potently interact with ABCB1 and ABCG2 transport functions suggesting influences on bioavailability of xenobiotics and pharmaceuticals.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Transportadores de Cassetes de Ligação de ATP/fisiologia , Depsipeptídeos/toxicidade , Fusarium/patogenicidade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/fisiologia , Micotoxinas/toxicidade , Proteínas de Neoplasias/fisiologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Cálcio/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos
16.
J Proteome Res ; 8(5): 2501-10, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19222175

RESUMO

Metastasis in melanoma is associated with poor prognosis. Early detection may thus substantially improve patient survival. Here we present a novel biomarker discovery strategy based on proteome profiling and secretome analysis of primary cells. Tumor associated stroma cells secrete proteins that may act as powerful tumor promoters. This cell cooperativity is reversible and may thus be directly accessible to therapeutic intervention. The onset of these characteristic events seems to precede tumor progression. Thus, proteins specifically secreted by these cells may serve as early disease biomarkers. Due to the leaky nature of newly formed blood vessels and the increased hydrostatic pressure within tumors, secreted proteins are most plausibly shed into the blood. Our analysis strategy is based on three different model systems, including established cultured cell lines, animal model systems, and clinical human samples. The feasibility is demonstrated with secretome and proteome profiles generated from normal human skin fibroblasts in comparison to melanoma-associated fibroblasts isolated from mouse xenografts and fibroblasts from bone marrow of multiple myeloma patients. Further mutual comparisons were enabled including proteome profiles of melanocytes and M24met melanoma cells. All shotgun proteomics data are accessible via the PRIDE database. Among others, the candidate biomarkers GPX5, secreted by melanoma cells, in addition to periostin and stanniocalcin-1, which are expressed by melanoma-associated fibroblasts were identified. In conclusion, this is a novel strategy to identify diagnostic marker proteins aiding early detection of metastatic melanoma and to improve our understanding of pathomechanisms involving the microenvironment to enable the design of novel therapeutic strategies.


Assuntos
Biomarcadores Tumorais/análise , Melanoma Experimental/metabolismo , Proteoma/análise , Proteômica/métodos , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Estudos de Viabilidade , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Espectrometria de Massas , Melanócitos/citologia , Melanócitos/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos SCID , Metástase Neoplásica , Proteoma/metabolismo , Transplante Heterólogo
17.
Cancer Lett ; 277(2): 218-26, 2009 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-19171421

RESUMO

Enzastaurin (LY317615.HCl) is an oral selective PKC-beta inhibitor with antiproliferative efficacy in various tumor models. This study was designed to investigate whether combination therapy with Enzastaurin and other targeted agents including Sorafenib and Sunitinib enhanced anti-tumor efficacy in renal cell carcinoma cell lines. Enzastaurin alone presented not active in renal cell carcinoma cell lines. Both Sorafenib and Sunitinib with Enzastaurin at concentrations feasible in vivo showed a synergistic reduction of viable RCC cells by inhibiting cell growth through inhibition of phospho-S6-kinase and GSK3-beta. The combination of Enzastaurin with Sorafenib and Sunitinib seems highly encouraging and warrants further investigation in vivo.


Assuntos
Antineoplásicos/farmacologia , Benzenossulfonatos/farmacologia , Proliferação de Células/efeitos dos fármacos , Indóis/farmacologia , Piridinas/farmacologia , Pirróis/farmacologia , Carcinoma de Células Renais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Niacinamida/análogos & derivados , Compostos de Fenilureia , Proteína Quinase C , Proteína Quinase C beta , Proteínas Quinases S6 Ribossômicas/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas/metabolismo , Transdução de Sinais , Sorafenibe , Sunitinibe
18.
Cancer Causes Control ; 20(2): 147-52, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18802780

RESUMO

PURPOSE: AURKA is a centrosome-associated serine/threonine kinase involved in mitotic chromosomal segregation. The AURKA gene is located on chromosome 20q13, also known as HPC20 prostate cancer susceptibility locus. Therefore, we investigated in this Caucasian case-control study two single nucleotide polymorphisms (SNPs) of the AURKA gene, rs8173 located in the 3'-untranslated region (G1891C) and rs2273535 in exon 5 (Phe31Ile), and their association with prostate cancer risk. METHODS: DNA was extracted from peripheral blood of 824 prostate cancer patients and 1,081 control patients with benign prostatic hyperplasia (BPH). Genotypes were determined using 5'-nuclease TaqMan assays. Multiple logistic regressions were performed to calculate odds ratios (OR) and confidence intervals (CI) and to adjust for confounders. RESULTS: The odds ratios calculated relative to the wild-type were for the homozygous polymorphic genotypes 1.11 (95% CI = 0.70-1.76) for rs8173 and 1.32 (95% CI = 0.76-2.31) for rs2273535, respectively. Stratified analyses according to Gleason score showed also no statistically significant association for the investigated polymorphisms and prostate cancer risk. CONCLUSIONS: The two investigated SNPs in AURKA were not found to be associated with prostate cancer risk. Other common SNPs of AURKA should be investigated in further studies because of its location on a prostate cancer susceptibility locus.


Assuntos
Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases/genética , Idoso , Aurora Quinase A , Aurora Quinases , Estudos de Casos e Controles , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Fatores de Risco
19.
Psychooncology ; 18(2): 179-86, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18677710

RESUMO

PURPOSE: To find out how patients perceived the disclosure of news about their cancer as regards the physician counselling and how they perceived the flow of information between hospital-based and family physicians. METHODS: 272 cancer patients were polled with a 16-item questionnaire. RESULTS: 252 cancer patients, 92.6% of those asked, completed the questionnaire. 37.7% (f:35.4%, m:41.8%) stated that the fact that they had cancer was presented to them 'very empathically' or 'empathically'. 62.3% (f:64.7%, m:58.3%) stated that it was presented to them 'not so empathically' or ' not at all empathically'. When patients had been counselled by family physicians they were more likely to state that it had been done 'very empathically' or 'empathically', in contrast to when they had been counselled by hospital-oncologists or self-employed specialists (81.8% vs. 41.2% vs. 41.2%; p=0.001). Significantly more patients thought that they had been given adequate opportunity to ask the questions they considered important when counselled by a family physician (81.8%) as compared to counselling by a hospital-oncologist (43.5%; p=0.002) or a self-employed specialist (44.3%; p=0.001). 56.8% preferred to discuss the suggested cancer therapies with an oncologist. 87.5% of patients considered the exchange of information between the hospital-based specialists and their family physician 'very important' or 'important'; more than half of all patients stated that this exchange of information was 'rather poor' or 'poor'. CONCLUSIONS: Oncologists should involve family physicians in disclosing bad news to patients. There are considerable deficiencies regarding information-exchange in cancer care in Austria.


Assuntos
Aconselhamento , Neoplasias/psicologia , Satisfação do Paciente , Relações Médico-Paciente , Revelação da Verdade , Áustria , Empatia , Feminino , Humanos , Relações Interprofissionais , Masculino , Oncologia , Pessoa de Meia-Idade , Atenção Primária à Saúde
20.
Mol Cancer Ther ; 7(10): 3408-19, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18852144

RESUMO

Fibroblast growth factors (FGF) and their high-affinity receptors (FGFR) represent an extensive cellular growth and survival system. Aim of this study was to evaluate the contribution of FGF/FGFR-mediated signals to the malignant growth of non-small cell lung cancer (NSCLC) and to assess their potential as targets for therapeutic interventions. Multiple FGFR mRNA splice variants were coexpressed in NSCLC cells (n = 16) with predominance of FGFR1. Accordingly, both expression of a dominant-negative FGFR1 (dnFGFR1) IIIc-green fluorescent protein fusion protein and application of FGFR small-molecule inhibitors (SU5402 and PD166866) significantly reduced growth, survival, clonogenicity, and migratory potential of the majority of NSCLC cell lines. Moreover, dnFGFR1 expression completely blocked or at least significantly attenuated s.c. tumor formation of NSCLC cells in severe combined immunodeficient mice. Xenograft tumors expressing dnFGFR1 exhibited significantly reduced size and mitosis rate, enhanced cell death, and decreased tissue invasion. When FGFR inhibitors were combined with chemotherapy, antagonistic to synergistic in vitro anticancer activities were obtained depending on the application schedule. In contrast, simultaneous blockage of FGFR- and epidermal growth factor receptor-mediated signals exerted synergistic effects. In summary, FGFR-mediated signals in cooperation with those transmitted by epidermal growth factor receptor are involved in growth and survival of human NSCLC cells and should be considered as targets for combined therapeutic approaches.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/terapia , Inibidores de Proteínas Quinases/farmacologia , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Processamento Alternativo/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Genes Dominantes , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Fenótipo , RNA Mensageiro , Receptores de Fatores de Crescimento de Fibroblastos/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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