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1.
Eur Thyroid J ; 13(6)2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39382341

RESUMO

Objective: The ultrasound evaluation of thyroid nodules (TNs) in patient selection for fine needle aspiration (FNA) requires both uniformly accepted definitions of each nodule characteristic and extensive experience from the examiner. We hypothesized that nodule echogenicity alone may provide comparable performance to more complex approaches in patient selection for FNA. Patients and methods: Seven highly experienced investigators from four countries evaluated, online, the ultrasound (US) video recordings of 123 histologically verified TN by answering 17 nodule characteristics-related questions. The diagnostic performances of five TN image reporting and data systems (TIRADS) were compared to making decisions based solely on the echogenicity of the nodule for indicating FNA in 110 nodules ≥10 mm. Results: In the 10-20 mm size range, the sensitivities and specificities of the five TIRADS systems in identifying malignant nodules were 80.5-91.0% and 31.4-50.9%, respectively. Had FNA been recommended for all hypoechoic nodules, disregarding other US characteristics, comparable sensitivity and specificity (87.5% and 43.4%, respectively) were obtained. Compared to nodules >20 mm, a higher proportion of cancers were hypoechoic in the 10-20 mm size range (87.2% vs 77.8%, P = 0.05). In the 10-20 mm size range, compared to hypoechoic nodules, a significantly lower proportion of isoechoic nodules demonstrated suspicious findings (70.7% vs 30.0%, P < 0.05). Conclusion: In contrast to >20 mm diameter nodules, the recommendation of FNA may rely on a single US feature, echogenicity, in the 10-20 mm size range. If independently confirmed in larger cohorts, this may simplify nodule evaluation in this size range.


Assuntos
Seleção de Pacientes , Sensibilidade e Especificidade , Nódulo da Glândula Tireoide , Ultrassonografia , Humanos , Nódulo da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/diagnóstico por imagem , Projetos Piloto , Biópsia por Agulha Fina , Feminino , Masculino , Pessoa de Meia-Idade , Ultrassonografia/métodos , Adulto , Idoso , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem
2.
Eur Thyroid J ; 12(2)2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36692389

RESUMO

Objective: Thyroid nodule ultrasound characteristics are used as an indication for fine-needle aspiration cytology, usually as the basis for Thyroid Imaging Reporting and Data System (TIRADS) score calculation. Few studies on interobserver variation are available, all of which are based on analysis of preselected still ultrasound images and often lack surgical confirmation. Methods: After the blinded online evaluation of video recordings of the ultrasound examinations of 47 consecutive malignant and 76 consecutive benign thyroid lesions, 7 experts from 7 thyroid centers answered 17 TIRADS-related questions. Surgical histology was the reference standard. Interobserver variations of each ultrasound characteristic were compared using Gwet's AC1 inter-rater coefficients; higher values mean better concordance, the maximum being 1.0. Results: On a scale from 0.0 to 1.0, the Gwet's AC1 values were 0.34, 0.53, 0.72, and 0.79 for the four most important features in decision-making, i.e. irregular margins, microcalcifications, echogenicity, and extrathyroidal extension, respectively. The concordance in the discrimination between mildly/moderately and very hypoechogenic nodules was 0.17. The smaller the nodule size the better the agreement in echogenicity, and the larger the nodule size the better the agreement on the presence of microcalcifications. Extrathyroidal extension was correctly identified in just 45.8% of the cases. Conclusions: Examination of video recordings, closely simulating the real-world situation, revealed substantial interobserver variation in the interpretation of each of the four most important ultrasound characteristics. In view of the importance for the management of thyroid nodules, unambiguous and widely accepted definitions of each nodule characteristic are warranted, although it remains to be investigated whether this diminishes observer variation.


Assuntos
Calcinose , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Variações Dependentes do Observador , Ultrassonografia/métodos
3.
Orv Hetil ; 163(30): 1196-1205, 2022 Jul 24.
Artigo em Húngaro | MEDLINE | ID: mdl-35895442

RESUMO

Introduction: There have been significant changes in the treatment protocol for rectal tumors in recent decades, greatly reducing the rate of local recurrence and distant metastasis, thereby increasing overall survival. Method: We performed a retrospective processing and statistical analysis of the data of 362 patients with rectal cancer who underwent local neoadjuvant chemoradiotherapy and then underwent surgical treatment between 1 January 2010 and 31 December 2017 at the Institute of Surgery of the University of Debrecen. We compared the response rate and overall survival results of our patients with local neoadjuvant treatment to the outcomes of total neoadjuvant treatment reported by the recent large international studies. Results: We experienced complete pathological regression in 8.6% of our patients. After neoadjuvant therapy, 10.7% of our patients experienced distant metastasis at the time of the operation or within 3 months period thereafter. In our study, the rate of response to the neoadjuvant treatment was a prognostic factor independent of the stage at di-agnosis and recognition. The groups with better response produced significantly better survival results. Conclusion: The total neoadjuvant treatment doubled the number of patients with complete pathological response, and the incidence of distant metastasis was by 7% lower in both recent international studies compared to the local neoadjuvant group. 85% of our patients were T3-4N+ stage at the time of recognition. Given the 10.7% rate of dis- tant metastases detected at the time of surgery or within 3 months in our patient population, we can state that ap- proximately half of our patients would have benefited from the administration of total neoadjuvant therapy which produced better outcomes. Based on this conclusion, we decided to introduce the total neoadjuvant therapy protocol in our department for treatment of patients with advanced rectal tumors.


Assuntos
Quimiorradioterapia , Neoplasias Retais , Humanos , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
4.
Eur Thyroid J ; 10(5): 416-424, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34540712

RESUMO

BACKGROUND: Thyroid nodule image reporting and data systems (TIRADS) provide the indications for fine-needle aspiration (FNA) based on a combination of nodule sonographic features and size. We compared the TIRADS-based recommendations for FNA with those based on the personal expertise of qualified US investigators in the diagnosis of thyroid malignancy. METHODS: Seven highly experienced ultrasound (US) investigators from 4 countries evaluated, online, the US video recordings of 123 histologically verified thyroid nodules. Technical resources provided the operators with a diagnostic approach close to the real-world practice. Altogether, 4,305 TIRADS scores were computed. The combined diagnostic potential of TIRADS (TIRSYS) and the personal recommendations of the investigators (PERS) were compared against 3 possible goals: to recognize all malignant lesions (allCA), nonpapillary plus non-pT1 papillary cancers (nPnT1PCA), or stage II-IV cancers (st2-4CA). RESULTS: For allCA and nPnT1PCA, TIRSYS had lower sensitivity than PERS (69.8 vs. 87.2 and 83.5 vs. 92.6%, respectively, p <0.01), while in st2-4CA the sensitivities were the same (99.1 vs. 98.6% and TIRSYS vs. PERS, respectively). TIRSYS had a higher specificity than PERS in all 3 types of cancers (p < 0.001). PERS recommended FNA in a similar proportion of lesions smaller or larger than 1 cm (76.9 vs. 82.7%; ns). CONCLUSIONS: Recommendations for FNA based on the investigators' US expertise demonstrated a better sensitivity for thyroid cancer in the 2 best prognostic groups, while TIRADS methodology showed superior specificity over the full prognostic range of cancers. Thus, personal experience provided more accurate diagnoses of malignancy, missing a lower number of small thyroid cancers, but the TIRADS approach resulted in a similar accuracy for the diagnosis of potentially aggressive lesions while sparing a relevant number of FNAs. Until it is not clearly stated what the goal of the US evaluation is, that is to diagnose all or only clinically relevant thyroid cancers, it cannot be determined whether one diagnostic approach is superior to the other for recommending FNA.

5.
Comput Struct Biotechnol J ; 19: 4032-4041, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377368

RESUMO

Throughout evolution, DNA transposons provide a recurrent supply of genetic information to give rise to novel gene functions by fusion of their transposase domain to various domains of host-encoded proteins. One of these "domesticated", transposase-derived factors is SETMAR/Metnase which is a naturally occurring fusion protein that consists of a histone-lysine methyltransferase domain and an HsMar1 transposase. To elucidate the biological role of SETMAR, it is crucial to identify genomic targets to which SETMAR specifically binds and link these sites to the regulation of gene expression. Herein, we mapped the genomic landscape of SETMAR binding in a near-haploid human leukemia cell line (HAP1) in order to identify on-target and off-target binding sites at high resolution and to elucidate their role in terms of gene expression. Our analysis revealed a perfect correlation between SETMAR and inverted terminal repeats (ITRs) of HsMar1 transposon remnants, which are considered as natural target sites for SETMAR binding. However, we did not detect any untargeted events at non-ITR sequences, calling into question previously proposed off-target binding sites. We identified sequence fidelity of the ITR motif as a key factor for determining the binding affinity of SETMAR for chromosomes, as higher conservation of ITR sequences resulted in increased affinity for chromatin and stronger repression of SETMAR-bound gene loci. These associations highlight how SETMAR's chromatin binding fine-tune gene regulatory networks in human tumour cells.

6.
Life (Basel) ; 10(12)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352712

RESUMO

The polyphyletic group of black fungi within the Ascomycota (Arthoniomycetes, Dothideomycetes, and Eurotiomycetes) is ubiquitous in natural and anthropogenic habitats. Partly because of their dark, melanin-based pigmentation, black fungi are resistant to stresses including UV- and ionizing-radiation, heat and desiccation, toxic metals, and organic pollutants. Consequently, they are amongst the most stunning extremophiles and poly-extreme-tolerant organisms on Earth. Even though ca. 60 black fungal genomes have been sequenced to date, [mostly in the family Herpotrichiellaceae (Eurotiomycetes)], the class Dothideomycetes that hosts the largest majority of extremophiles has only been sparsely sampled. By sequencing up to 92 species that will become reference genomes, the "Shed light in The daRk lineagES of the fungal tree of life" (STRES) project will cover a broad collection of black fungal diversity spread throughout the Fungal Tree of Life. Interestingly, the STRES project will focus on mostly unsampled genera that display different ecologies and life-styles (e.g., ant- and lichen-associated fungi, rock-inhabiting fungi, etc.). With a resequencing strategy of 10- to 15-fold depth coverage of up to ~550 strains, numerous new reference genomes will be established. To identify metabolites and functional processes, these new genomic resources will be enriched with metabolomics analyses coupled with transcriptomics experiments on selected species under various stress conditions (salinity, dryness, UV radiation, oligotrophy). The data acquired will serve as a reference and foundation for establishing an encyclopedic database for fungal metagenomics as well as the biology, evolution, and ecology of the fungi in extreme environments.

7.
Cancers (Basel) ; 11(9)2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461945

RESUMO

In breast cancer patients, the diversity of the microbiome decreases, coinciding with decreased production of cytostatic bacterial metabolites like lithocholic acid (LCA). We hypothesized that LCA can modulate oxidative stress to exert cytostatic effects in breast cancer cells. Treatment of breast cancer cells with LCA decreased nuclear factor-2 (NRF2) expression and increased Kelch-like ECH associating protein 1 (KEAP1) expression via activation of Takeda G-protein coupled receptor (TGR5) and constitutive androstane receptor (CAR). Altered NRF2 and KEAP1 expression subsequently led to decreased expression of glutathione peroxidase 3 (GPX3), an antioxidant enzyme, and increased expression of inducible nitric oxide synthase (iNOS). The imbalance between the pro- and antioxidant enzymes increased cytostatic effects via increased levels of lipid and protein oxidation. These effects were reversed by the pharmacological induction of NRF2 with RA839, tBHQ, or by thiol antioxidants. The expression of key components of the LCA-elicited cytostatic pathway (iNOS and 4HNE) gradually decreased as the breast cancer stage advanced. The level of lipid peroxidation in tumors negatively correlated with the mitotic index. The overexpression of iNOS, nNOS, CAR, KEAP1, NOX4, and TGR5 or the downregulation of NRF2 correlated with better survival in breast cancer patients, except for triple negative cases. Taken together, LCA, a metabolite of the gut microbiome, elicits oxidative stress that slows down the proliferation of breast cancer cells. The LCA-oxidative stress protective pathway is lost as breast cancer progresses, and the loss correlates with poor prognosis.

8.
DNA Repair (Amst) ; 84: 102642, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300387

RESUMO

Unravelling the origin of genetic alterations from point mutations to chromosomal rearrangements was greatly enhanced by the discovery of RNA-DNA hybrids (R-loops) that behave as hotspots of genomic instability in a variety of organisms. Current models suggest that uncontrolled R-loops are a hazard to genome integrity, therefore, identifying proteins that are involved in recognising and signalling R-loop structures are of key importance. Herein we analysed key RNA-DNA hybrid binding proteins in humans taking advantage of large-scale gene expression, survival rate, and drug-sensitivity data from cancer genomics databases. We show that expression of RNA-DNA hybrid binding proteins in various cancer types is associated with survival and may have contrasting outcomes in responding to therapeutic treatments. Based on the revealed pharmacogenomic landscape of human RNA-DNA hybrid binding proteins, we propose that R-loops and R-loop binding proteins are potentially relevant new epigenetic markers and therapeutic targets in multiple cancers.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ligação a DNA/metabolismo , Neoplasias/genética , Estruturas R-Loop , Proteínas de Ligação a RNA/metabolismo , Linhagem Celular Tumoral , Instabilidade Genômica , Humanos , Ligação Proteica/efeitos dos fármacos
9.
Atherosclerosis ; 277: 262-266, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30270056

RESUMO

BACKGROUND AND AIMS: Familial hypercholesterolemia (FH) is one of the most frequent diseases with monogenic inheritance. Previous data indicated that the heterozygous form occurred in 1:250 people. Based on these reports, around 36,000-40,000 people are estimated to have FH in Hungary, however, there are no exact data about the frequency of the disease in our country. Therefore, we initiated a cooperation with a clinical site partner company that provides modern data mining methods, on the basis of medical and statistical records, and we applied them to two major hospitals in the Northern Great Plain region of Hungary to find patients with a possible diagnosis of FH. METHODS: Medical records of 1,342,124 patients were included in our study. From the mined data, we calculated Dutch Lipid Clinic Network (DLCN) scores for each patient and grouped them according to the criteria to assess the likelihood of the diagnosis of FH. We also calculated the mean lipid levels before the diagnosis and treatment. RESULTS: We identified 225 patients with a DLCN score of 6-8 (mean total cholesterol: 9.38 ±â€¯3.0 mmol/L, mean LDL-C: 7.61 ±â€¯2.4 mmol/L), and 11,706 patients with a DLCN score of 3-5 (mean total cholesterol: 7.34 ±â€¯1.2 mmol/L, mean LDL-C: 5.26 ±â€¯0.8 mmol/L). CONCLUSIONS: The analysis of more regional and country-wide data and more frequent measurements of total cholesterol and LDL-C levels would increase the number of FH cases discovered. Data mining seems to be ideal for filtering and screening of FH in Hungary.


Assuntos
Colesterol/sangue , Mineração de Dados/métodos , Aprendizado Profundo , Registros Eletrônicos de Saúde , Hiperlipoproteinemia Tipo II/diagnóstico , Programas de Rastreamento/métodos , Adolescente , Adulto , Biomarcadores/sangue , LDL-Colesterol/sangue , Feminino , Predisposição Genética para Doença , Humanos , Hungria/epidemiologia , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/epidemiologia , Hiperlipoproteinemia Tipo II/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes , Prognóstico , Adulto Jovem
10.
Front Immunol ; 9: 151, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29445380

RESUMO

Tumors are composed of abnormally transformed cell types and tissues that differ from normal tissues in their genetic and epigenetic makeup, metabolism, and immunology. Molecular compounds that modulate the immune response against neoplasms offer promising new strategies to combat cancer. Inhibitors targeting the indoleamine-2,3-dioxygenase 1 enzyme (IDO1) represent one of the most potent therapeutic opportunities to inhibit tumor growth. Herein, we assess the biochemical role of IDO1 in tumor metabolism and immune surveillance, and review current diagnostic and therapeutic approaches that are intended to increase the effectiveness of immunotherapies against highly aggressive and difficult-to-treat IDO-expressing cancers.


Assuntos
Indolamina-Pirrol 2,3,-Dioxigenase/fisiologia , Neoplasias/enzimologia , Animais , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia
11.
Biochem Biophys Res Commun ; 490(3): 868-875, 2017 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-28647357

RESUMO

Lysine 27 to methionine (K27 M) mutation of the histone variant H3.3 drives the formation of an aggressive glioblastoma multiforme tumor in infants. Here we analyzed how the methionine substitution alters the stability of H3.3 nucleosomes in vitro and modifies its kinetic properties in live cells. We also determined whether the presence of mutant nucleosomes perturbed the mobility of the PRC2 subunit Ezh2 (enhancer-of-zeste homolog 2). We found that K27 M nucleosomes maintained the wild-type molecular architecture both at the level of bulk histones and single nucleosomes and followed similar diffusion kinetics to wild-type histones in live cells. Nevertheless, we observed a remarkable differential recovery of Ezh2 in response to transcriptional stress that was accompanied by a faster diffusion rate of the mobile fraction of Ezh2 and a significantly increased immobile fraction, suggesting tighter chromatin binding of Ezh2 upon transcription inhibition. The differential recovery of Ezh2 was dependent on transcription, however, it was independent from K27 M mutation status. These biophysical characteristics shed more light on the mechanism of histone H3.3 K27M in glioma genesis in relation to the kinetic properties of Ezh2.


Assuntos
Histonas/genética , Mutação Puntual , Animais , Proteína Potenciadora do Homólogo 2 de Zeste/análise , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Transferência Ressonante de Energia de Fluorescência , Glioblastoma/genética , Glioblastoma/metabolismo , Células HeLa , Histonas/análise , Histonas/metabolismo , Humanos , Nucleossomos/química , Nucleossomos/genética , Nucleossomos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ativação Transcricional , Xenopus laevis
12.
Genome Biol ; 18(1): 28, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28196534

RESUMO

BACKGROUND: The fungal genus Aspergillus is of critical importance to humankind. Species include those with industrial applications, important pathogens of humans, animals and crops, a source of potent carcinogenic contaminants of food, and an important genetic model. The genome sequences of eight aspergilli have already been explored to investigate aspects of fungal biology, raising questions about evolution and specialization within this genus. RESULTS: We have generated genome sequences for ten novel, highly diverse Aspergillus species and compared these in detail to sister and more distant genera. Comparative studies of key aspects of fungal biology, including primary and secondary metabolism, stress response, biomass degradation, and signal transduction, revealed both conservation and diversity among the species. Observed genomic differences were validated with experimental studies. This revealed several highlights, such as the potential for sex in asexual species, organic acid production genes being a key feature of black aspergilli, alternative approaches for degrading plant biomass, and indications for the genetic basis of stress response. A genome-wide phylogenetic analysis demonstrated in detail the relationship of the newly genome sequenced species with other aspergilli. CONCLUSIONS: Many aspects of biological differences between fungal species cannot be explained by current knowledge obtained from genome sequences. The comparative genomics and experimental study, presented here, allows for the first time a genus-wide view of the biological diversity of the aspergilli and in many, but not all, cases linked genome differences to phenotype. Insights gained could be exploited for biotechnological and medical applications of fungi.


Assuntos
Adaptação Biológica , Aspergillus/classificação , Aspergillus/genética , Biodiversidade , Genoma Fúngico , Genômica , Aspergillus/metabolismo , Biomassa , Carbono/metabolismo , Biologia Computacional/métodos , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Metilação de DNA , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Redes Reguladoras de Genes , Genômica/métodos , Humanos , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Família Multigênica , Oxirredutases/metabolismo , Filogenia , Plantas/metabolismo , Plantas/microbiologia , Metabolismo Secundário/genética , Transdução de Sinais , Estresse Fisiológico/genética
13.
Liver Int ; 36(11): 1628-1638, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27031405

RESUMO

BACKGROUND & AIMS: Innate immune system dysfunction is common in advanced cirrhosis, with a central role of the monocyte/macrophage system. Monocytes and macrophages express the scavenger receptor CD163, which is regulated by inflammatory mediators. Cleavage of the receptor leads to the formation of soluble (s)CD163 that represents an anti-inflammatory response. We aimed to study the clinical importance of sCD163 in cirrhosis. METHODS: Sera of 378 patients were assayed for sCD163 by ELISA [193 outpatients and 185 patients with acute decompensation (AD)]. A 5-year follow-up observational study was conducted to assess the possible association between sCD163 level and poor disease outcomes. RESULTS: sCD163 level was associated with disease severity, but not with the presence of varices or prior variceal bleeding. In outpatients, sCD163 level did not predict the development of disease-specific complications or the long-term mortality. In patients with AD episode, sCD163 level was significantly higher compared to outpatients but only in the presence of bacterial infection (INF) (AD-INF:4586, AD-NON-INF:3792 and outpatients: 3538 ng/ml, P < 0.015 and P = 0.001, respectively). sCD163 level gradually increased according to severity of infection. During bacterial infections, high sCD163 level (>7000 ng/ml) was associated with increased mortality rate (42% vs. 17%, P < 0.001) and was identified as an independent predictor of 28-day mortality (hazard ratio:2.96, 95% confidence intervals:1.27-6.95) in multivariate Cox-regression model comprising aetiology, co-morbidity, model for end-stage liver disease score and leucocyte count as covariates. CONCLUSIONS: High sCD163 level is useful to identify patients with high-risk of death during an AD episode complicated by bacterial infection. This finding serves as an additional hint towards the significance of anti-inflammatory response during bacterial infection.


Assuntos
Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Infecções Bacterianas/complicações , Cirrose Hepática/complicações , Cirrose Hepática/mortalidade , Macrófagos/imunologia , Receptores de Superfície Celular/sangue , Idoso , Biomarcadores/sangue , Feminino , Seguimentos , Hemorragia Gastrointestinal/sangue , Humanos , Hungria , Imunidade Inata , Contagem de Leucócitos , Ativação de Macrófagos , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Análise Multivariada , Modelos de Riscos Proporcionais , Índice de Gravidade de Doença , Centros de Atenção Terciária
14.
BMC Genomics ; 6: 182, 2005 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-16368011

RESUMO

BACKGROUND: In addition to their cytotoxic nature, reactive oxygen species (ROS) are also signal molecules in diverse cellular processes in eukaryotic organisms. Linking genome-wide transcriptional changes to cellular physiology in oxidative stress-exposed Aspergillus nidulans cultures provides the opportunity to estimate the sizes of peroxide (O2(2-)), superoxide (O2*-) and glutathione/glutathione disulphide (GSH/GSSG) redox imbalance responses. RESULTS: Genome-wide transcriptional changes triggered by diamide, H2O2 and menadione in A. nidulans vegetative tissues were recorded using DNA microarrays containing 3533 unique PCR-amplified probes. Evaluation of LOESS-normalized data indicated that 2499 gene probes were affected by at least one stress-inducing agent. The stress induced by diamide and H2O2 were pulse-like, with recovery after 1 h exposure time while no recovery was observed with menadione. The distribution of stress-responsive gene probes among major physiological functional categories was approximately the same for each agent. The gene group sizes solely responsive to changes in intracellular O2(2-), O2*- concentrations or to GSH/GSSG redox imbalance were estimated at 7.7, 32.6 and 13.0 %, respectively. Gene groups responsive to diamide, H2O2 and menadione treatments and gene groups influenced by GSH/GSSG, O2(2-) and O2*- were only partly overlapping with distinct enrichment profiles within functional categories. Changes in the GSH/GSSG redox state influenced expression of genes coding for PBS2 like MAPK kinase homologue, PSK2 kinase homologue, AtfA transcription factor, and many elements of ubiquitin tagging, cell division cycle regulators, translation machinery proteins, defense and stress proteins, transport proteins as well as many enzymes of the primary and secondary metabolisms. Meanwhile, a separate set of genes encoding transport proteins, CpcA and JlbA amino acid starvation-responsive transcription factors, and some elements of sexual development and sporulation was ROS responsive. CONCLUSION: The existence of separate O2(2-), O2*- and GSH/GSSG responsive gene groups in a eukaryotic genome has been demonstrated. Oxidant-triggered, genome-wide transcriptional changes should be analyzed considering changes in oxidative stress-responsive physiological conditions and not correlating them directly to the chemistry and concentrations of the oxidative stress-inducing agent.


Assuntos
Aspergillus nidulans/genética , Diamida/farmacologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genoma Fúngico , Peróxido de Hidrogênio/farmacologia , Transcrição Gênica/efeitos dos fármacos , Vitamina K 3/farmacologia , Aspergillus nidulans/efeitos dos fármacos , Aspergillus nidulans/fisiologia , Glutationa/farmacologia , Dissulfeto de Glutationa/farmacologia , Cinética
15.
Cancer Lett ; 222(1): 17-22, 2005 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-15837537

RESUMO

Rats (FLF1) were pretreated with 2 and 20 mg/kg/day fluvastatin (Flu), and after 6 weeks, hepatocellular tumor cells were inoculated under the left renal capsule. At different times, growth and pyruvate kinase (PK) activity of the primary tumors and lymph node metastases were determined. Flu had a dose-dependent inhibitory effect on primary and metastatic tumors, and the inhibitory effect on growth and PK activity in metastases were higher than in primary tumors. Finally, Flu had an earlier inhibitory effect on the early appeared PK activity in metastases than in primary tumors.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Ácidos Graxos Monoinsaturados/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Indóis/uso terapêutico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Piruvato Quinase/antagonistas & inibidores , Animais , Fluvastatina , Rim , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Metástase Linfática/prevenção & controle , Masculino , Ratos , Ratos Endogâmicos
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