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1.
Plant Commun ; 5(1): 100646, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37415333

RESUMO

Gene cloning in repeat-rich polyploid genomes remains challenging. Here, we describe a strategy for overcoming major bottlenecks in cloning of the powdery mildew resistance gene (R-gene) Pm69 derived from tetraploid wild emmer wheat. A conventional positional cloning approach was not effective owing to suppressed recombination. Chromosome sorting was compromised by insufficient purity. A Pm69 physical map, constructed by assembling Oxford Nanopore Technology (ONT) long-read genome sequences, revealed a rapidly evolving nucleotide-binding leucine-rich repeat (NLR) R-gene cluster with structural variations. A single candidate NLR was identified by anchoring RNA sequencing reads from susceptible mutants to ONT contigs and was validated by virus-induced gene silencing. Pm69 is likely a newly evolved NLR and was discovered in only one location across the wild emmer wheat distribution range in Israel. Pm69 was successfully introgressed into cultivated wheat, and a diagnostic molecular marker was used to accelerate its deployment and pyramiding with other R-genes.


Assuntos
Genes de Plantas , Triticum , Triticum/genética , Genes de Plantas/genética , Mapeamento Cromossômico , Clonagem Molecular , Família Multigênica
2.
Nat Prod Rep ; 40(1): 62-88, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35796260

RESUMO

Covering: 2011 up to the end of 2021.Fungal nonribosomal peptides (NRPs) and the related polyketide-nonribosomal peptide hybrid products (PK-NRPs) are a prolific source of bioactive compounds, some of which have been developed into essential drugs. The synthesis of these complex natural products (NPs) utilizes nonribosomal peptide synthetases (NRPSs), multidomain megaenzymes that assemble specific peptide products by sequential condensation of amino acids and amino acid-like substances, independent of the ribosome. NRPSs, collaborating polyketide synthase modules, and their associated tailoring enzymes involved in product maturation represent promising targets for NP structure diversification and the generation of small molecule unnatural products (uNPs) with improved or novel bioactivities. Indeed, reprogramming of NRPSs and recruiting of novel tailoring enzymes is the strategy by which nature evolves NRP products. The recent years have witnessed a rapid development in the discovery and identification of novel NRPs and PK-NRPs, and significant advances have also been made towards the engineering of fungal NRP assembly lines to generate uNP peptides. However, the intrinsic complexities of fungal NRP and PK-NRP biosynthesis, and the large size of the NRPSs still present formidable conceptual and technical challenges for the rational and efficient reprogramming of these pathways. This review examines key examples for the successful (and for some less-successful) re-engineering of fungal NRPS assembly lines to inform future efforts towards generating novel, biologically active peptides and PK-NRPs.


Assuntos
Proteínas Fúngicas , Policetídeos , Proteínas Fúngicas/metabolismo , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Peptídeos/química , Peptídeo Sintases/metabolismo , Biossíntese de Peptídeos Independentes de Ácido Nucleico
3.
Probiotics Antimicrob Proteins ; 15(2): 400-410, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36459386

RESUMO

Bacterial vaginosis (BV) is a common vaginal disease associated with abnormal changes in the vaginal microbiome. Our previous study found that Lactobacillus rhamnosus has a good therapeutic effect on bacterial vaginosis by inhibiting the most prominent bacterium associated with BV, Gardnerella vaginalis. In this study, we show that acetic acid and lactic acid are the main substances in the cell-free supernatant (CFS) of L. rhamnosus that inhibit the growth of G. vaginalis. Further study on the mechanism showed that acetic acid and lactic acid alter the morphology of the G. vaginalis cells, eventually causing the cells to shrink or burst, resulting in exudation of their intracellular contents. In addition, these two organic acids also dissipate the membrane potential of bacterial cells, affecting their synthesis of ATP. A reduced activity of the Na+/K+-ATPase leads to abnormal ATP metabolism, and ultimately inhibits the growth and reproduction of G. vaginalis. Our study provides valuable information for the widespread application of L. rhamnosus in the treatment of bacterial vaginosis.


Assuntos
Anti-Infecciosos , Lacticaseibacillus rhamnosus , Vaginose Bacteriana , Humanos , Feminino , Gardnerella vaginalis , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/microbiologia , Vagina/microbiologia , Ácido Acético , Trifosfato de Adenosina
4.
Microbiol Spectr ; 10(1): e0257721, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138171

RESUMO

Entomopathogenic Photorhabdus bacteria (Enterobacteriaceae: Gamma-proteobacteria), the natural symbionts of Heterorhabditis nematodes, are a rich source for the discovery of biologically active secondary metabolites (SMs). This study describes the isolation of three nematicidal SMs from in vitro culture supernatants of the Arizona-native Photorhabdus luminescens sonorensis strain Caborca by bioactivity-guided fractionation. Nuclear magnetic resonance spectroscopy and comparison to authentic synthetic standards identified these bioactive metabolites as trans-cinnamic acid (t-CA), (4E)-5-phenylpent-4-enoic acid (PPA), and indole. PPA and t-CA displayed potent, concentration-dependent nematicidal activities against the root-knot nematode (Meloidogyne incognita) and the citrus nematode (Tylenchulus semipenetrans), two economically and globally important plant parasitic nematodes (PPNs) that are ubiquitous in the United States. Southwest. Indole showed potent, concentration-dependent nematistatic activity by inducing the temporary rigid paralysis of the same targeted nematodes. While paralysis was persistent in the presence of indole, the nematodes recovered upon removal of the compound. All three SMs were found to be selective against the tested PPNs, exerting little effects on non-target species such as the bacteria-feeding nematode Caenorhabditis elegans or the entomopathogenic nematodes Steinernema carpocapsae, Heterorhabditis bacteriophora, and Hymenocallis sonorensis. Moreover, none of these SMs showed cytotoxicity against normal or neoplastic human cells. The combination of t-CA + PPA + indole had a synergistic nematicidal effect on both targeted PPNs. Two-component mixtures prepared from these SMs revealed complex, compound-, and nematode species-dependent interactions. These results justify further investigations into the chemical ecology of Photorhabdus SMs, and recommend t-CA, PPA and indole, alone or in combinations, as lead compounds for the development of selective and environmentally benign nematicides against the tested PPNs. IMPORTANCE Two phenylpropanoid and one alkaloid secondary metabolites were isolated and identified from culture filtrates of Photorhabdus l. sonorensis strain Caborca. The three identified metabolites showed selective nematicidal and/or nematistatic activities against two important plant parasitic nematodes, the root-knot nematode (Meloidogyne incognita) and the citrus nematode (Tylenchulus semipenetrans). The mixture of all three metabolites had a synergistic nematicidal effect on both targeted nematodes, while other combinations showed compound- and nematode-dependent interactions.


Assuntos
Anti-Helmínticos/farmacologia , Photorhabdus/química , Doenças das Plantas/parasitologia , Metabolismo Secundário , Tylenchoidea/efeitos dos fármacos , Animais , Anti-Helmínticos/química , Anti-Helmínticos/metabolismo , Cinamatos/química , Cinamatos/metabolismo , Cinamatos/farmacologia , Indóis/química , Indóis/metabolismo , Indóis/farmacologia , Estrutura Molecular , Photorhabdus/metabolismo , Tylenchoidea/crescimento & desenvolvimento
5.
ACS Omega ; 6(23): 15486-15498, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34151127

RESUMO

A total of 12 new cycloartane- and lanostane-type triterpenoids including 16-deoxyargentatin A (1), 16-deoxyisoargentatin A (2), 7-oxoisoargentatin A (3), 24-epi-argentatin H (4), 24-O-p-anisoylargentatin C (5), 24-O-trans-cinnamoylargentatin C (6), 16-dehydroargentatin C (7), 16,17(20)-didehydroargentatin C (8), isoargentatin C (9), isoargentatin H (10), 3-epi-quisquagenin (11), and isoquisquagenin (12) together with 10 known triterpenoids (13-22) were isolated from the resin of Parthenium argentatum AZ-2 obtained as a byproduct of Bridgestone guayule rubber production. The structures of new triterpenoids 1-12 and argentatin H (13), which has previously been characterized as its diacetate (23), were elucidated by extensive analysis of their spectroscopic data and chemical conversions, and the known compounds 14-22 were identified by comparison of their spectroscopic data with those reported. Of these, 13, 14, and 18 exhibited weak cytotoxic activity for several cancer cell lines.

6.
New Phytol ; 229(5): 2812-2826, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33176001

RESUMO

Pm1a, the first powdery mildew resistance gene described in wheat, is part of a complex resistance (R) gene cluster located in a distal region of chromosome 7AL that has suppressed genetic recombination. A nucleotide-binding, leucine-rich repeat (NLR) immune receptor gene was isolated using mutagenesis and R gene enrichment sequencing (MutRenSeq). Stable transformation confirmed Pm1a identity which induced a strong resistance phenotype in transgenic plants upon challenge with avirulent Blumeria graminis (wheat powdery mildew) pathogens. A high-density genetic map of a B. graminis family segregating for Pm1a avirulence combined with pathogen genome resequencing and RNA sequencing (RNAseq) identified AvrPm1a effector gene candidates. In planta expression identified an effector, with an N terminal Y/FxC motif, that induced a strong hypersensitive response when co-expressed with Pm1a in Nicotiana benthamiana. Single chromosome enrichment sequencing (ChromSeq) and assembly of chromosome 7A suggested that suppressed recombination around the Pm1a region was due to a rearrangement involving chromosomes 7A, 7B and 7D. The cloning of Pm1a and its identification in a highly rearranged region of chromosome 7A provides insight into the role of chromosomal rearrangements in the evolution of this complex resistance cluster.


Assuntos
Ascomicetos , Triticum , Ascomicetos/genética , Cromossomos , Resistência à Doença/genética , Doenças das Plantas/genética , Triticum/genética
7.
mSphere ; 5(6)2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239367

RESUMO

Total biosynthesis or whole-cell biocatalytic production of sulfated small molecules relies on the discovery and implementation of appropriate sulfotransferase enzymes. Although fungi are prominent biocatalysts and have been used to sulfate drug-like phenolics, no gene encoding a sulfotransferase enzyme has been functionally characterized from these organisms. Here, we identify a phenolic sulfotransferase, FgSULT1, by genome mining from the plant-pathogenic fungus Fusarium graminearum PH-1. We expressed FgSULT1 in a Saccharomyces cerevisiae chassis to modify a broad range of benzenediol lactones and their nonmacrocyclic congeners, together with an anthraquinone, with the resulting unnatural natural product (uNP) sulfates displaying increased solubility. FgSULT1 shares low similarity with known animal and plant sulfotransferases. Instead, it forms a sulfotransferase family with putative bacterial and fungal enzymes for phase II detoxification of xenobiotics and allelochemicals. Among fungi, putative FgSULT1 homologues are encoded in the genomes of Fusarium spp. and a few other genera in nonsyntenic regions, some of which may be related to catabolic sulfur recycling. Computational structure modeling combined with site-directed mutagenesis revealed that FgSULT1 retains the key catalytic residues and the typical fold of characterized animal and plant sulfotransferases. Our work opens the way for the discovery of hitherto unknown fungal sulfotransferases and provides a synthetic biological and enzymatic platform that can be adapted to produce bioactive sulfates, together with sulfate ester standards and probes for masked mycotoxins, precarcinogenic toxins, and xenobiotics.IMPORTANCE Sulfation is an expedient strategy to increase the solubility, bioavailability, and bioactivity of nutraceuticals and clinically important drugs. However, chemical or biological synthesis of sulfoconjugates is challenging. Genome mining, heterologous expression, homology structural modeling, and site-directed mutagenesis identified FgSULT1 of Fusarium graminearum PH-1 as a cytosolic sulfotransferase with the typical fold and active site architecture of characterized animal and plant sulfotransferases, despite low sequence similarity. FgSULT1 homologues are sparse in fungi but form a distinct clade with bacterial sulfotransferases. This study extends the functionally characterized sulfotransferase superfamily to the kingdom Fungi and demonstrates total biosynthetic and biocatalytic synthetic biological platforms to produce unnatural natural product (uNP) sulfoconjugates. Such uNP sulfates may be utilized for drug discovery in human and veterinary medicine and crop protection. Our synthetic biological methods may also be adapted to generate masked mycotoxin standards for food safety and environmental monitoring applications and to expose precarcinogenic xenobiotics.


Assuntos
Fusarium/genética , Sulfotransferases/química , Sulfotransferases/genética , Sulfotransferases/metabolismo , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Humanos , Mutagênese Sítio-Dirigida , Células Vero
8.
J Agric Food Chem ; 68(13): 3995-4004, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32133853

RESUMO

Antioxidant metabolites contribute to alleviating oxidative stress caused by reactive oxygen species (ROS) in microorganisms. We utilized oxidative stressors such as hydrogen peroxide supplementation to increase the yield of the bioactive secondary metabolite antioxidant antrodin C in submerged fermentations of the medicinal mushroom Antrodia cinnamomea. Changes in the superoxide dismutase and catalase activities of the cells indicate that ROS are critical to promote antrodin C biosynthesis, while the ROS production inhibitor diphenyleneiodonium cancels the productivity-enhancing effects of H2O2. Transcriptomic analysis suggests that key enzymes in the mitochondrial electron transport chain are repressed during oxidative stress, leading to ROS accumulation and triggering the biosynthesis of antioxidants such as antrodin C. Accordingly, rotenone, an inhibitor of the electron transport chain complex I, mimics the antrodin C productivity-enhancing effects of H2O2. Delineating the steps connecting oxidative stress with increased antrodin C biosynthesis will facilitate the fine-tuning of strategies for rational fermentation process improvement.


Assuntos
Antioxidantes/metabolismo , Antrodia/metabolismo , Maleimidas/metabolismo , Antrodia/efeitos dos fármacos , Antrodia/genética , Antrodia/crescimento & desenvolvimento , Fermentação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Metabolismo Secundário , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
9.
mBio ; 11(1)2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019788

RESUMO

Despite the important biological activities of natural product naphthoquinones, the biosynthetic pathways of and resistance mechanisms against such compounds remain poorly understood in fungi. Here, we report that the genes responsible for the biosynthesis of Monascus naphthoquinones (monasones) reside within the gene cluster for Monascus azaphilone pigments (MonAzPs). We elucidate the biosynthetic pathway of monasones by a combination of comparative genome analysis, gene knockouts, heterologous coexpression, and in vivo and in vitro enzymatic reactions to show that this pathway branches from the first polyketide intermediate of MonAzPs. Furthermore, we propose that the monasone subset of biosynthetic genes also encodes a two-tiered resistance strategy in which an inducible monasone-specific exporter expels monasones from the mycelia, while residual intracellular monasones may be rendered nontoxic through a multistep reduction cascade.IMPORTANCE The genes for Monascus naphthoquinone (monasone) biosynthesis are embedded in and form a composite supercluster with the Monascus azaphilone pigment biosynthetic gene cluster. Early biosynthetic intermediates are shared by the two pathways. Some enzymes encoded by the supercluster play double duty in contributing to both pathways, while others are specific for one or the other pathway. The monasone subcluster is independently regulated and inducible by elicitation with competing microorganisms. This study illustrates genomic and biosynthetic parsimony in fungi and proposes a potential path for the evolution of the mosaic-like azaphilone-naphthoquinone supercluster. The monasone subcluster also encodes a two-tiered self-resistance mechanism that models resistance determinants that may transfer to target microorganisms or emerge in cancer cells in case of naphthoquinone-type cytotoxic agents.


Assuntos
Monascus/efeitos dos fármacos , Monascus/genética , Família Multigênica , Naftoquinonas/metabolismo , Naftoquinonas/farmacologia , Vias Biossintéticas , Farmacorresistência Fúngica/genética , Monascus/metabolismo
10.
Ideggyogy Sz ; 72(1-2): 23-31, 2019 01 30.
Artigo em Húngaro | MEDLINE | ID: mdl-30785243

RESUMO

Background and purpose: To assess the extent to which pain therapy can improve chronic pain in a heterogeneous group of patients, its impact on their quality of life and the correlation of the changes with their age and the underlying disease. The investigation has its actuality by its impact on public health. Methods: a prospective, non-randomized, interventional, clinical cohort study was conducted under real-life conditions in a general pain clinic, which lasted for 6 months. Changes in pain intensity (VAS) and related quality of life changes (SF-36 HRQoL) were measured using validated internationally accepted questionnaires. The questionnaires were filled out by all patients on their own, so they provided information of self-esteem on their own. All patient post-treatment results were compared to pre-treatment results. The general quality of life changes found in our patients were compared to the representative norms of healthy population in Hungary. Subjects - patients participated voluntarily at their own decision in the survey. The underlying disease of chronic pain, age and gender of the patients did not limit the inclusion into the study. Results: Data of 231 patients were evaluated. After pain therapy, the decrease in intensity of pain was confirmed by VAS at p=0.002. This was linked to a quality of life change that has been shown to be p=0.003 for men, with p=0.002 in women with SF-36 HRQoL. Based on the correlation coefficients, the changes in quality of life improved regardless of the age of the patients and the nature of the underlying conditions causing the pain. Conclusion: Although analgesia is basicly a symptomatic therapy, our findings suggest that the reduction of pain improves the quality of life of patients independently from their, and the curability of the underlying and accompanying diseases.


Assuntos
Analgésicos/administração & dosagem , Anestesia Local/métodos , Dor Crônica/terapia , Bloqueio Nervoso/métodos , Qualidade de Vida , Dor Crônica/psicologia , Estudos de Coortes , Feminino , Humanos , Hungria , Masculino , Cuidados Paliativos , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento
11.
J Pain Res ; 12: 307-315, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30679920

RESUMO

BACKGROUND: Pancreatic cancer is a malignant disease with a high mortality rate and severe pain that is challenging to manage. To reduce the excruciating abdominal pain, opioids and adjuvant agents are conventionally used. OBJECTIVES: PRNCPB is a treatment of neural therapy. The number of studies assessing the effect on patients' QoL is limited and inconsistent. With this study, we intended to address this issue. STUDY DESIGN: A prospective nonrandomized study with a series of cases of unresectable pancreatic cancer was conducted. SETTING: The study was performed at our pain clinic under real life conditions. MATERIALS AND METHODS: A total number of 16 patients with severe abdominal pain were enrolled in the study all of whom had responded to combined systemic analgesic therapy inadequately and had intolerable side effects contraindicating further increase in dose. The efficacy of this invasive, palliative analgesic procedure was evaluated 35 days after PRNCPB was performed. Primary outcomes were changed in pain intensity using the VAS questionnaire. Secondary outcomes were improved in QoL using the SF-36 questionnaire. Changes in pain medications and adverse reactions were monitored. RESULTS: After PRNCPB patients experienced a significant decrease (P=0.002) in pain intensity as shown by the VAS score, and a decreased opiate demand. Their QoL scores considering effect sizes also improved (P<0.001). No complications attributable to PRNCPB were observed during the study period. Additionally, no adverse drug reactions were observed. LIMITATIONS: Detection, observation, and reporting bias can be estimated as moderate. Selection bias was not detected. CONCLUSION: Our results give preliminary evidence that PRNCPB might be helpful as an additional treatment to conventional pain management in end-stage pancreatic cancer patients. PRNCPB seems to improve QoL in these patients in a time frame of at least 5 weeks after intervention.

12.
Br J Cancer ; 119(9): 1086-1093, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30361524

RESUMO

BACKGROUND: This phase 1 dose-escalation trial studied MM-302, a novel HER2-targeted PEGylated antibody-liposomal doxorubicin conjugate, in HER2-positive locally advanced/metastatic breast cancer. METHODS: Patients were enrolled in four cohorts: MM-302 monotherapy (8, 16, 30, 40, and 50 mg/m2 every 4 weeks [q4w]); MM-302 (30 or 40 mg/m2 q4w) plus trastuzumab (4 mg/kg q2w); MM-302 (30 mg/m2) plus trastuzumab (6 mg/kg) q3w; MM-302 (30 mg/m2) plus trastuzumab (6 mg/kg) and cyclophosphamide (450 mg/m2) q3w. RESULTS: Sixty-nine patients were treated. The most common adverse events (AEs) were fatigue and nausea. Grade 3/4 AEs of special interest included neutropenia, fatigue, mucosal inflammation, anemia, thrombocytopenia, febrile neutropenia, and palmar-plantar erythrodysesthesia. The MTD was not reached. With MM-302 ≥ 30 mg/m2, overall response rate (ORR) was 13% and median progression-free survival (mPFS) 7.4 months (95% CI: 3·5-10·9) in all arms. In 25 anthracycline-naïve patients, ORR was 28·0% and mPFS 10·9 months (95% CI: 1·8-15·3). Imaging with 64Cu-labeled MM-302 visualized tumor-drug penetrance in tumors throughout the body, including the brain. CONCLUSION: MM-302 monotherapy, in combination with trastuzumab, or trastuzumab plus cyclophosphamide, was well tolerated and showed promising efficacy. The selected phase 2 MM-302 dose was 30 mg/m2 plus 6 mg/kg trastuzumab q3w.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Ciclofosfamida/administração & dosagem , Doxorrubicina/análogos & derivados , Imunoconjugados/administração & dosagem , Receptor ErbB-2/genética , Anticorpos de Cadeia Única/administração & dosagem , Trastuzumab/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Encéfalo/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética , Ciclofosfamida/efeitos adversos , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/farmacocinética , Esquema de Medicação , Feminino , Humanos , Imunoconjugados/efeitos adversos , Imunoconjugados/farmacocinética , Anticorpos de Cadeia Única/efeitos adversos , Anticorpos de Cadeia Única/farmacocinética , Análise de Sobrevida , Trastuzumab/efeitos adversos , Resultado do Tratamento
13.
Proc Natl Acad Sci U S A ; 115(22): E4980-E4989, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29760061

RESUMO

Glycosylation is a prominent strategy to optimize the pharmacokinetic and pharmacodynamic properties of drug-like small-molecule scaffolds by modulating their solubility, stability, bioavailability, and bioactivity. Glycosyltransferases applicable for "sugarcoating" various small-molecule acceptors have been isolated and characterized from plants and bacteria, but remained cryptic from filamentous fungi until recently, despite the frequent use of some fungi for whole-cell biocatalytic glycosylations. Here, we use bioinformatic and genomic tools combined with heterologous expression to identify a glycosyltransferase-methyltransferase (GT-MT) gene pair that encodes a methylglucosylation functional module in the ascomycetous fungus Beauveria bassiana The GT is the founding member of a family nonorthologous to characterized fungal enzymes. Using combinatorial biosynthetic and biocatalytic platforms, we reveal that this GT is a promiscuous enzyme that efficiently modifies a broad range of drug-like substrates, including polyketides, anthraquinones, flavonoids, and naphthalenes. It yields both O- and N-glucosides with remarkable regio- and stereospecificity, a spectrum not demonstrated for other characterized fungal enzymes. These glucosides are faithfully processed by the dedicated MT to afford 4-O-methylglucosides. The resulting "unnatural products" show increased solubility, while representative polyketide methylglucosides also display increased stability against glycoside hydrolysis. Upon methylglucosidation, specific polyketides were found to attain cancer cell line-specific antiproliferative or matrix attachment inhibitory activities. These findings will guide genome mining for fungal GTs with novel substrate and product specificities, and empower the efficient combinatorial biosynthesis of a broad range of natural and unnatural glycosides in total biosynthetic or biocatalytic formats.


Assuntos
Antineoplásicos , Descoberta de Drogas , Fungos , Glicosiltransferases , Metiltransferases , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungos/enzimologia , Fungos/genética , Fungos/metabolismo , Glicosilação , Glicosiltransferases/química , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Humanos , Metiltransferases/química , Metiltransferases/genética , Metiltransferases/metabolismo , Policetídeo Sintases/química , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Policetídeos/metabolismo , Células Vero
14.
J Nat Prod ; 80(8): 2215-2223, 2017 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-28749671

RESUMO

Eight new ß-resorcylic acid lactones (RALs), including the hypothemycin-type compounds paecilomycins N-P (1-3) and the radicicol-type metabolites dechloropochonin I (4), monocillins VI (5) and VII (6), 4'-hydroxymonocillin IV (7), and 4'-methoxymonocillin IV (8), along with nine known RALs (9-17), were isolated from the cultures of Paecilomyces sp. SC0924. Compounds 1 and 2 feature a novel 6/11/5 ring system, and 3 is the first 5'-keto RAL. The structures of 1-8 were elucidated on the basis of extensive spectroscopic analysis, X-ray diffraction analysis, and theoretical calculations of ECD spectra. Compounds 3, 5, and 6 exhibit cytotoxicity against MCF-7, A549, and HeLa cells, and compounds 5 and 7 display antifungal activity against Peronophythora litchii.


Assuntos
Éteres de Hidroxibenzoatos/isolamento & purificação , Éteres de Hidroxibenzoatos/farmacologia , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/farmacologia , Lactonas/isolamento & purificação , Lactonas/farmacologia , Macrolídeos/farmacologia , Paecilomyces/química , Phytophthora/química , Zearalenona/análogos & derivados , Antifúngicos , Células HeLa , Humanos , Éteres de Hidroxibenzoatos/química , Hidroxibenzoatos/química , Lactonas/química , Macrolídeos/química , Estrutura Molecular , Difração de Raios X , Zearalenona/química , Zearalenona/farmacologia
15.
Diagn Pathol ; 12(1): 20, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28222768

RESUMO

BACKGROUND: Studies have partly demonstrated the clinical validity of Ki-67 as a predictive marker in the neoadjuvant setting, but the question of the best cut-off points as well as the importance of this marker as a prognostic factor in partial responder/non-responder groups remains uncertain. METHODS: One hundred twenty patients diagnosed with invasive breast cancer and treated with neoadjuvant chemotherapy (NAC) between 2002 and 2013 were retrospectively recruited to this study. The optimal cut-off value for Ki-67 labeling index (LI) to discriminate response to treatment was assessed by receiver operating characteristic (ROC) curve analysis. Kaplan-Meier curve estimation, log-rank test and cox regression analysis were carried out to reveal the association between Ki-67 categories and survival (DMFS = Distant metastases-free survival, OS = Overall survival). RESULTS: Twenty three out of 120 patients (19.2%) achieved pathologic complete remission (pCR), whereas partial remission (pPR) and no response (pNR) to neoadjuvant chemotherapy (NAC) was detected in 60.8% and 20.0%, respectively. The distribution of subtypes showed a significant difference in pathological response groups (p < 0.001). Most of the TNBC cases were represented in pCR group. The most relevant cut-off value for the Ki-67 distinguishing pCR from pNR cases was 20% (p = 0.002). No significant threshold for Ki-67 was found regarding DMFS (p = 0.208). Considering OS, the optimal cut-off point occurred at 15% Ki-67 (p = 0.006). The pPR group represented a significant Ki-67 threshold at 30% regarding OS (p = 0.001). Ki-67 and pPR subgroups were not significantly associated (p = 0.653). For prognosis prediction, Ki-67 at 30% cut-off value (p = 0.040) furthermore subtype (p = 0.037) as well as pathological response (p = 0.044) were suitable to separate patients into good and unfavorable prognosis cohorts regarding OS. However, in multivariate analyses, only Ki-67 at 30% threshold (p = 0.029), and subtype (p = 0.008) were independently linked to OS. CONCLUSIONS: NAC is more efficient in tumors with at least 20% Ki-67 LI. Both Ki-67 LI and subtype showed a significant association with pathological response. Ki-67 LI represented independent prognostic potential to OS in our neoadjuvant patient cohort, while pathological response did not. Additionally, our data also suggest that if a tumor is non-responder to NAC, increased Ki-67 is a poor prognostic marker.


Assuntos
Neoplasias da Mama/patologia , Antígeno Ki-67/análise , Terapia Neoadjuvante , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Área Sob a Curva , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Quimioterapia Adjuvante , Estudos de Coortes , Estudos Transversais , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos
16.
Virchows Arch ; 470(3): 275-283, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28101678

RESUMO

The aim of our retrospective study was to analyze patterns of subtype specific metastatic spread and to identify the time course of distant metastases. A consecutive series of 490 patients with breast cancer who underwent surgery and postoperative treatment at Semmelweis University, Hungary, and diagnosed between the years 2000 and 2007 was identified from the archives of the 2nd Department of Pathology, Hungary. Molecular subtypes were defined based on the 2011 St. Gallen recommendations. Statistical analysis was performed with SPSS Statistics for Windows, Version 22.0. Distant metastasis free survival (DMFS) was defined as the time elapsed between the first pathological diagnosis of the tumor and the first distant metastasis detection. Distant metastases were detected in 124 patients. Mean time to develop metastasis was 29 months (range 0-127 months). The longest DMFS was observed in the Luminal A (LUMA) subtype (mean 39 months) whereas the shortest was seen in the HER2-positive (HER2+) subtype (mean 21 months; p = 0.012). We confirmed that HER2+ tumors carry a higher risk for distant metastases (42.1%). LUMA-associated metastases were found to be solitary in 59% of cases, whereas HER2+ tumors showed multiple metastases in 79.2% of cases. LUMA tumors showed a preference for bone-only metastasis as compared with HER2+ and triple negative breast cancer (TNBC) cases, which exhibited a higher rate of brain metastasis. The most frequent second metastatic sites of hormone receptor (HR) positive tumors were the lung and liver, whereas the brain was the most affected organ in HR-negative (HR-) cases. Tumor subtypes differ in DMFS and in pattern of distant metastases. HER2+ tumors featured the most aggressive clinical course. Further identification of subtype-specific factors influencing prognosis might have an impact on clinical care and decision-making.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , Receptor ErbB-2/análise , Receptor ErbB-2/biossíntese , Receptores de Estrogênio/análise , Receptores de Estrogênio/biossíntese , Receptores de Progesterona/análise , Receptores de Progesterona/biossíntese , Estudos Retrospectivos
17.
BMC Cancer ; 16: 352, 2016 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-27259714

RESUMO

BACKGROUND: Human epidermal growth factor receptor 2 (HER2)-positive breast cancer is a particularly aggressive form of the disease, and ultimately progresses in patients with metastases on standard therapies. Anthracyclines, such as doxorubicin, are an effective treatment for HER2-positive breast cancer, particularly when administered in combination with trastuzumab - however, doxorubicin-related cardiotoxicity has limited its use. Many patients are therefore never treated with anthracyclines, even upon disease progression, despite the potential for benefit. MM-302 is a novel, HER2-targeted antibody-liposomal doxorubicin conjugate that specifically targets HER2-overexpressing cells. Preclinical and Phase 1 data suggest that MM-302, as a monotherapy or in combination with trastuzumab, could be effective for managing previously treated, anthracycline-naïve, HER2-positive breast cancer, without the cardiotoxicity observed with free doxorubicin formulations. METHODS/DESIGN: HERMIONE is an open-label, multicenter, randomized (1:1) Phase 2 trial of MM-302 plus trastuzumab versus chemotherapy of physician's choice (gemcitabine, capecitabine, or vinorelbine) plus trastuzumab planned to enroll 250 anthracycline-naïve patients with locally advanced/metastatic HER2-positive breast cancer. Key inclusion criteria are: previous treatment with trastuzumab (with or without pertuzumab) in any setting; refractory or intolerant to pertuzumab (refractory to pertuzumab defined as progression in the locally advanced or metastatic setting, or disease recurrence during or within 12 months of completing pertuzumab-containing neoadjuvant and/or adjuvant therapy); and disease progression on, or intolerant to, ado-trastuzumab emtansine for locally advanced or metastatic disease. The trial is currently being conducted at sites in the USA, Canada, and Western Europe. Treatment will be administered in 21-day cycles, and will be continued until disease progression or unacceptable toxicity. The primary endpoint is independently assessed progression-free survival (PFS). Tumor response will be assessed every 6 weeks, and defined according to RECIST v1.1. Secondary endpoints include investigator-assessed PFS, overall survival (OS), OS rates at 6 months and 1 year, objective response rates, safety and tolerability, quality of life, and the pharmacokinetic profile of MM-302 plus trastuzumab. DISCUSSION: The HERMIONE study will evaluate the efficacy and safety of MM-302 plus trastuzumab in patients with refractory HER2-positive advanced/metastatic breast cancer for whom there are no standard of care therapies with a proven survival advantage. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02213744 . Registration date: 06AUG2014.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/análogos & derivados , Imunoconjugados/uso terapêutico , Terapia de Alvo Molecular/métodos , Projetos de Pesquisa , Anticorpos de Cadeia Única/uso terapêutico , Neoplasias da Mama/patologia , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Feminino , Humanos , Imunotoxinas/uso terapêutico , Metástase Neoplásica , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/administração & dosagem , Trastuzumab/efeitos adversos
18.
PLoS One ; 10(4): e0122254, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25830331

RESUMO

A novel Gram-negative bacterium, designated ZWT, was isolated from a soil sample of the Western Desert of China, and its phenotypic properties and phylogenetic position were investigated using a polyphasic approach. Growth occurred on TGY medium at 5-42°C with an optimum of 30°C, and at pH 7.0-11.0 with an optimum of pH 9.0. The predominant cellular fatty acids were summed feature 3 (C16:1ω7c/C16:1ω6c or C16:1ω6c/C16:1ω7c) (39.22%), iso-C15:0 (27.91%), iso-C17:0 3OH (15.21%), C16:0 (4.98%), iso-C15:0 3OH (3.03%), C16:0 3OH (5.39%) and C14:0 (1.74%). The major polar lipid of strain ZWT is phosphatidylethanolamine. The only menaquinone observed was MK-7. The GC content of the DNA of strain ZWT is 44.9 mol%. rDNA phylogeny, genome relatedness and chemotaxonomic characteristics all indicate that strain ZWT represents a novel species of the genus Sphingobacterium. We propose the name S. deserti sp. nov., with ZWT (= KCTC 32092T = ACCC 05744T) as the type strain. Whole genome optical mapping and next-generation sequencing was used to derive a finished genome sequence for strain ZWT, consisting of a circular chromosome of 4,615,818 bp in size. The genome of strain ZWT features 3,391 protein-encoding and 48 tRNA-encoding genes. Comparison of the predicted proteome of ZWT with those of other sphingobacteria identified 925 species-unique proteins that may contribute to the adaptation of ZWT to its native, extremely arid and inhospitable environment. As the first finished genome sequence for any Sphingobacterium, our work will serve as a useful reference for subsequent sequencing and mapping efforts for additional strains and species within this genus.


Assuntos
Genoma Bacteriano , Microbiologia do Solo , Sphingobacterium/genética , China , Mapeamento Cromossômico , Análise de Sequência de DNA , Sphingobacterium/isolamento & purificação
19.
J Clin Pathol ; 68(4): 274-82, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25595275

RESUMO

AIMS: To assess the expression of the following cell cycle regulatory proteins in primary metastatic breast carcinomas (MBCs) and on availability in matched distant metastases (DMs): Ki67, cyclin A, geminin and aurora-kinase A (aurkA); and to compare the expression of these markers in early MBC (EMBC) and late MBC separated into groups according to median time point on metastatic event occurred (28 months). METHODS: The expression of the above mentioned markers was analysed in a total of 47 primary MBCs and 59 DMs (out of which 37 were pairs) by immunohistochemistry. Fourteen breast carcinomas with no relapse over a 10-year follow-up period were utilised as control cases (CBC). RESULTS: Among the MBCs, 22 metastasised to the bone, 4 to the lung and 21 to the central nervous system (CNS). Geminin (p<0.001) and Ki67 (p=0.001) were increased in the MBCs while aurkA and cyclin A showed no difference when compared with CBCs. There were no differences between aurkA, cyclin A and geminin expression in MBCs and DMs in general. Expression of Ki67 was, however, elevated (p=0.027) in DMs. In CNS metastases all markers showed elevated expression as compared to MBCs. In bone metastases, geminin was lower (p<0.001) compared with primary MBCs. In the metastases of the lung, the evaluated markers did not show different expression. According to the median follow-up until the metastatic event, Ki67 was found to be significantly elevated in EMBC (p=0.018). CONCLUSIONS: Ki67 index and geminin distinguish a fraction of MBC with worse prognosis, showing increased levels in the latter in comparison to CBC being tumour-free over a 10-year follow-up period. Ki67 could possibly identify a group of MBCs that develop early DMs.


Assuntos
Aurora Quinase A/análise , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Carcinoma/enzimologia , Carcinoma/secundário , Proliferação de Células , Ciclina A/análise , Geminina/análise , Antígeno Ki-67/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/enzimologia , Neoplasias Ósseas/secundário , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Carcinoma/mortalidade , Carcinoma/terapia , Neoplasias do Sistema Nervoso Central/enzimologia , Neoplasias do Sistema Nervoso Central/secundário , Intervalo Livre de Doença , Feminino , Humanos , Hungria , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Análise Serial de Tecidos
20.
Proc Natl Acad Sci U S A ; 111(34): 12354-9, 2014 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25049383

RESUMO

Combinatorial biosynthesis aspires to exploit the promiscuity of microbial anabolic pathways to engineer the synthesis of new chemical entities. Fungal benzenediol lactone (BDL) polyketides are important pharmacophores with wide-ranging bioactivities, including heat shock response and immune system modulatory effects. Their biosynthesis on a pair of sequentially acting iterative polyketide synthases (iPKSs) offers a test case for the modularization of secondary metabolic pathways into "build-couple-pair" combinatorial synthetic schemes. Expression of random pairs of iPKS subunits from four BDL model systems in a yeast heterologous host created a diverse library of BDL congeners, including a polyketide with an unnatural skeleton and heat shock response-inducing activity. Pairwise heterocombinations of the iPKS subunits also helped to illuminate the innate, idiosyncratic programming of these enzymes. Even in combinatorial contexts, these biosynthetic programs remained largely unchanged, so that the iPKSs built their cognate biosynthons, coupled these building blocks into chimeric polyketide intermediates, and catalyzed intramolecular pairing to release macrocycles or α-pyrones. However, some heterocombinations also provoked stuttering, i.e., the relaxation of iPKSs chain length control to assemble larger homologous products. The success of such a plug and play approach to biosynthesize novel chemical diversity bodes well for bioprospecting unnatural polyketides for drug discovery.


Assuntos
Técnicas de Química Combinatória/métodos , Policetídeo Sintases/química , Policetídeo Sintases/metabolismo , Policetídeos/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Animais , Linhagem Celular Tumoral , Resposta ao Choque Térmico/efeitos dos fármacos , Humanos , Lactonas/química , Lactonas/metabolismo , Lactonas/farmacologia , Camundongos , Policetídeo Sintases/genética , Policetídeos/química , Policetídeos/farmacologia , Subunidades Proteicas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
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