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1.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38152979

RESUMO

The identification and characterization of essential genes are central to our understanding of the core biological functions in eukaryotic organisms, and has important implications for the treatment of diseases caused by, for example, cancers and pathogens. Given the major constraints in testing the functions of genes of many organisms in the laboratory, due to the absence of in vitro cultures and/or gene perturbation assays for most metazoan species, there has been a need to develop in silico tools for the accurate prediction or inference of essential genes to underpin systems biological investigations. Major advances in machine learning approaches provide unprecedented opportunities to overcome these limitations and accelerate the discovery of essential genes on a genome-wide scale. Here, we developed and evaluated a large language model- and graph neural network (LLM-GNN)-based approach, called 'Bingo', to predict essential protein-coding genes in the metazoan model organisms Caenorhabditis elegans and Drosophila melanogaster as well as in Mus musculus and Homo sapiens (a HepG2 cell line) by integrating LLM and GNNs with adversarial training. Bingo predicts essential genes under two 'zero-shot' scenarios with transfer learning, showing promise to compensate for a lack of high-quality genomic and proteomic data for non-model organisms. In addition, the attention mechanisms and GNNExplainer were employed to manifest the functional sites and structural domain with most contribution to essentiality. In conclusion, Bingo provides the prospect of being able to accurately infer the essential genes of little- or under-studied organisms of interest, and provides a biological explanation for gene essentiality.


Assuntos
Proteínas de Drosophila , Genes Essenciais , Camundongos , Animais , Proteômica , Drosophila melanogaster/genética , Fluxo de Trabalho , Redes Neurais de Computação , Proteínas/genética , Proteínas dos Microfilamentos/genética , Proteínas de Drosophila/genética
2.
PLoS Pathog ; 18(2): e1010288, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35167626

RESUMO

Urogenital schistosomiasis is caused by the blood fluke Schistosoma haematobium and is one of the most neglected tropical diseases worldwide, afflicting > 100 million people. It is characterised by granulomata, fibrosis and calcification in urogenital tissues, and can lead to increased susceptibility to HIV/AIDS and squamous cell carcinoma of the bladder. To complement available treatment programs and break the transmission of disease, sound knowledge and understanding of the biology and ecology of S. haematobium is required. Hybridisation/introgression events and molecular variation among members of the S. haematobium-group might effect important biological and/or disease traits as well as the morbidity of disease and the effectiveness of control programs including mass drug administration. Here we report the first chromosome-contiguous genome for a well-defined laboratory line of this blood fluke. An exploration of this genome using transcriptomic data for all key developmental stages allowed us to refine gene models (including non-coding elements) and annotations, discover 'new' genes and transcription profiles for these stages, likely linked to development and/or pathogenesis. Molecular variation within S. haematobium among some geographical locations in Africa revealed unique genomic 'signatures' that matched species other than S. haematobium, indicating the occurrence of introgression events. The present reference genome (designated Shae.V3) and the findings from this study solidly underpin future functional genomic and molecular investigations of S. haematobium and accelerate systematic, large-scale population genomics investigations, with a focus on improved and sustained control of urogenital schistosomiasis.


Assuntos
Variação Genética , Genoma de Protozoário , Schistosoma haematobium/genética , Esquistossomose Urinária/parasitologia , Transcriptoma , Animais , Cromossomos/parasitologia , Genes de Protozoários , Genoma , Estudo de Associação Genômica Ampla , Análise de Sequência de DNA
3.
Nature ; 562(7728): 526-531, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30333627

RESUMO

The implementation of targeted therapies for acute myeloid leukaemia (AML) has been challenging because of the complex mutational patterns within and across patients as well as a dearth of pharmacologic agents for most mutational events. Here we report initial findings from the Beat AML programme on a cohort of 672 tumour specimens collected from 562 patients. We assessed these specimens using whole-exome sequencing, RNA sequencing and analyses of ex vivo drug sensitivity. Our data reveal mutational events that have not previously been detected in AML. We show that the response to drugs is associated with mutational status, including instances of drug sensitivity that are specific to combinatorial mutational events. Integration with RNA sequencing also revealed gene expression signatures, which predict a role for specific gene networks in the drug response. Collectively, we have generated a dataset-accessible through the Beat AML data viewer (Vizome)-that can be leveraged to address clinical, genomic, transcriptomic and functional analyses of the biology of AML.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Genoma Humano/genética , Genômica , Leucemia Mieloide Aguda/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Conjuntos de Dados como Assunto , Exoma/genética , Feminino , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Masculino , Terapia de Alvo Molecular , Proteínas Nucleares/genética , Nucleofosmina , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Análise de Sequência de RNA , Fatores de Processamento de Serina-Arginina/genética
4.
Blood ; 137(7): 939-944, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32898857

RESUMO

Blinatumomab is currently approved for use as a single agent in relapsed and refractory acute lymphoblastic leukemia (ALL). Cytotoxicity is mediated via signaling through the T-cell receptor (TCR). There is now much interest in combining blinatumomab with targeted therapies, particularly in Philadelphia chromosome-positive ALL (Ph+ ALL). However, some second- and third-generation ABL inhibitors also potently inhibit Src family kinases that are important in TCR signaling. We combined ABL inhibitors and dual Src/ABL inhibitors with blinatumomab in vitro from both healthy donor samples and primary samples from patients with Ph+ ALL. Blinatumomab alone led to both T-cell proliferation and elimination of target CD19+ cells and enhanced production of interferon-γ (IFN-γ). The addition of the ABL inhibitors imatinib or nilotinib to blinatumomab did not inhibit T-cell proliferation or IFN-γ production. However, the addition of dasatinib or ponatinib inhibited T-cell proliferation and IFN-γ production. Importantly, there was no loss of CD19+ cells treated with blinatumomab plus dasatinib or ponatinib in healthy samples or samples with a resistant ABL T315I mutation by dasatinib in combination with blinatumomab. These in vitro findings bring pause to the excitement of combination therapies, highlighting the importance of maintaining T-cell function with targeted therapies.


Assuntos
Anticorpos Biespecíficos/farmacologia , Antineoplásicos/farmacologia , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Ativação Linfocitária/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-abl/antagonistas & inibidores , Linfócitos T/imunologia , Quinases da Família src/antagonistas & inibidores , Linfócitos B , Dasatinibe/farmacologia , Humanos , Mesilato de Imatinib/farmacologia , Imidazóis/farmacologia , Testes de Liberação de Interferon-gama , Células Jurkat , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Mutação de Sentido Incorreto , Proteínas de Neoplasias/fisiologia , Fosforilação/efeitos dos fármacos , Mutação Puntual , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-abl/genética , Piridazinas/farmacologia , Pirimidinas/farmacologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/enzimologia , Linfócitos T/metabolismo , Células Tumorais Cultivadas , Quinases da Família src/fisiologia
5.
Am J Hematol ; 97(5): 613-622, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35180323

RESUMO

Survival outcomes for relapsed/refractory pediatric acute myeloid leukemia (R/R AML) remain dismal. Epigenetic changes can result in gene expression alterations which are thought to contribute to both leukemogenesis and chemotherapy resistance. We report results from a phase I trial with a dose expansion cohort investigating decitabine and vorinostat in combination with fludarabine, cytarabine, and G-CSF (FLAG) in pediatric patients with R/R AML [NCT02412475]. Thirty-seven patients enrolled with a median age at enrollment of 8.4 (range, 1-20) years. There were no dose limiting toxicities among the enrolled patients, including two patients with Down syndrome. The recommended phase 2 dose of decitabine in combination with vorinostat and FLAG was 10 mg/m2 . The expanded cohort design allowed for an efficacy evaluation and the overall response rate among 35 evaluable patients was 54% (16 complete response (CR) and 3 complete response with incomplete hematologic recovery (CRi)). Ninety percent of responders achieved minimal residual disease (MRD) negativity (<0.1%) by centralized flow cytometry and 84% (n = 16) successfully proceeded to hematopoietic stem cell transplant. Two-year overall survival was 75.6% [95%CI: 47.3%, 90.1%] for MRD-negative patients vs. 17.9% [95%CI: 4.4%, 38.8%] for those with residual disease (p < .001). Twelve subjects (34%) had known epigenetic alterations with 8 (67%) achieving a CR, 7 (88%) of whom were MRD negative. Correlative pharmacodynamics demonstrated the biologic activity of decitabine and vorinostat and identified specific gene enrichment signatures in nonresponding patients. Overall, this therapy was well-tolerated, biologically active, and effective in pediatric patients with R/R AML, particularly those with epigenetic alterations.


Assuntos
Leucemia Mieloide Aguda , Linfoma , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Criança , Citarabina , Decitabina/uso terapêutico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Linfoma/tratamento farmacológico , Vorinostat
6.
Genomics ; 113(3): 1605-1615, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33677057

RESUMO

The Chinese liver fluke, Clonorchis sinensis, causes the disease clonorchiasis, affecting ~35 million people in regions of China, Vietnam, Korea and the Russian Far East. Chronic clonorchiasis causes cholangitis and can induce a malignant cancer, called cholangiocarcinoma, in the biliary system. Control in endemic regions is challenging, and often relies largely on chemotherapy with one anthelmintic, called praziquantel. Routine treatment carries a significant risk of inducing resistance to this anthelmintic in the fluke, such that the discovery of new interventions is considered important. It is hoped that the use of molecular technologies will assist this endeavour by enabling the identification of drug or vaccine targets involved in crucial biological processes and/or pathways in the parasite. Although draft genomes of C. sinensis have been published, their assemblies are fragmented. In the present study, we tackle this genome fragmentation issue by utilising, in an integrated way, advanced (second- and third-generation) DNA sequencing and informatic approaches to build a high-quality reference genome for C. sinensis, with chromosome-level contiguity and curated gene models. This substantially-enhanced genome provides a resource that could accelerate fundamental and applied molecular investigations of C. sinensis, clonorchiasis and/or cholangiocarcinoma, and assist in the discovery of new interventions against what is a highly significant, but neglected disease-complex.


Assuntos
Clonorquíase , Clonorchis sinensis , Animais , Sequência de Bases , China , Clonorquíase/tratamento farmacológico , Clonorquíase/epidemiologia , Clonorquíase/genética , Clonorchis sinensis/genética , Clonorchis sinensis/metabolismo , Humanos , Federação Russa
7.
Genomics ; 113(3): 1272-1280, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33677058

RESUMO

Here, we present a draft genome of the tapeworm Dipylidium caninum (family Dipylidiidae) and compare it with other cestode genomes. This draft genome of D. caninum is 110 Mb in size, has a repeat content of ~13.4% and is predicted to encode ~10,000 protein-coding genes. We inferred excretory/secretory molecules (representing the secretome), other key groups of proteins (including peptidases, kinases, phosphatases, GTPases, receptors, transporters and ion-channels) and predicted potential intervention targets for future evaluation. Using 144 shared single-copy orthologous sequences, we investigated the genetic relationships of cestodes for which nuclear genomes are available. This study provides first insights into the molecular biology of D. caninum and a new resource for comparative genomic and genetic explorations of this and other flatworms.


Assuntos
Cestoides , Infecções por Cestoides , Platelmintos , Animais , Cestoides/genética , Genômica
8.
EMBO Rep ; 20(7): e47546, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31267709

RESUMO

Progressive remodeling of the bone marrow microenvironment is recognized as an integral aspect of leukemogenesis. Expanding acute myeloid leukemia (AML) clones not only alter stroma composition, but also actively constrain hematopoiesis, representing a significant source of patient morbidity and mortality. Recent studies revealed the surprising resistance of long-term hematopoietic stem cells (LT-HSC) to elimination from the leukemic niche. Here, we examine the fate and function of residual LT-HSC in the BM of murine xenografts with emphasis on the role of AML-derived extracellular vesicles (EV). AML-EV rapidly enter HSC, and their trafficking elicits protein synthesis suppression and LT-HSC quiescence. Mechanistically, AML-EV transfer a panel of miRNA, including miR-1246, that target the mTOR subunit Raptor, causing ribosomal protein S6 hypo-phosphorylation, which in turn impairs protein synthesis in LT-HSC. While HSC functionally recover from quiescence upon transplantation to an AML-naive environment, they maintain relative gains in repopulation capacity. These phenotypic changes are accompanied by DNA double-strand breaks and evidence of a sustained DNA-damage response. In sum, AML-EV contribute to niche-dependent, reversible quiescence and elicit persisting DNA damage in LT-HSC.


Assuntos
Vesículas Extracelulares/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Nicho de Células-Tronco , Animais , Linhagem Celular Tumoral , Células Cultivadas , Quebras de DNA de Cadeia Dupla , Feminino , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Regulatória Associada a mTOR/genética , Proteína Regulatória Associada a mTOR/metabolismo , Proteína S6 Ribossômica/genética
9.
Pediatr Blood Cancer ; 68(4): e28892, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33438318

RESUMO

BACKGROUND: Entinostat is an oral small molecule inhibitor of class I histone deacetylases (HDAC), which has not previously been evaluated in pediatrics. We conducted a phase I trial to determine the maximum tolerated dose/recommended phase 2 dose (MTD/RP2D), toxicity profile, pharmacokinetics (PK), and pharmacodynamics (PD) of entinostat in children with relapsed or refractory solid tumors including central nervous system (CNS) malignancies. METHODS: A rolling six dose escalation design evaluated two dose levels. Entinostat oral tablet formulation was administered once per week, four doses per 28-day cycle. PK and PD studies were performed. RESULTS: Twenty-one eligible patients' median (range) age was 14 years (6-20). Six subjects were treated at 3 mg/m2 dose level and 15 were treated in 4 mg/m2 dose level. The study included patients with CNS tumors (n = 12), sarcomas (n = 6), or other solid tumors (n = 3). Eight patients were not fully evaluable for toxicity due to progression of disease prior to receiving the required percentage of protocol therapy. No cycle one dose-limiting toxicity (DLT) was observed at either dose level. A three-fold higher area under the curve (AUC) was achieved in our cohort compared to adults using a similar dosing schedule. The PD studies showed increase in acetylated lysine in peripheral blood leukocytes at both doses. CONCLUSIONS: Entinostat was well tolerated with no DLT observed. All patients experienced progression within the first two cycles, except one patient with ependymoma with stable disease. Based on PK and PD, the R2PD in pediatric patients with solid tumors is 4 mg/m2 orally administered once weekly.


Assuntos
Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias/tratamento farmacológico , Piridinas/uso terapêutico , Adolescente , Adulto , Antineoplásicos/efeitos adversos , Benzamidas/efeitos adversos , Criança , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Piridinas/efeitos adversos , Sarcoma/tratamento farmacológico , Adulto Jovem
10.
Int J Mol Sci ; 22(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670420

RESUMO

Long non-coding, tandem-repetitive regions in mitochondrial (mt) genomes of many metazoans have been notoriously difficult to characterise accurately using conventional sequencing methods. Here, we show how the use of a third-generation (long-read) sequencing and informatic approach can overcome this problem. We employed Oxford Nanopore technology to sequence genomic DNAs from a pool of adult worms of the carcinogenic parasite, Schistosoma haematobium, and used an informatic workflow to define the complete mt non-coding region(s). Using long-read data of high coverage, we defined six dominant mt genomes of 33.4 kb to 22.6 kb. Although no variation was detected in the order or lengths of the protein-coding genes, there was marked length (18.5 kb to 7.6 kb) and structural variation in the non-coding region, raising questions about the evolution and function of what might be a control region that regulates mt transcription and/or replication. The discovery here of the largest tandem-repetitive, non-coding region (18.5 kb) in a metazoan organism also raises a question about the completeness of some of the mt genomes of animals reported to date, and stimulates further explorations using a Nanopore-informatic workflow.


Assuntos
Genoma Helmíntico , Genoma Mitocondrial , Sequenciamento por Nanoporos , Schistosoma haematobium/genética , Sequências de Repetição em Tandem , Animais
11.
Molecules ; 26(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068691

RESUMO

Due to widespread multi-drug resistance in parasitic nematodes of livestock animals, there is an urgent need to discover new anthelmintics with distinct mechanisms of action. Extending previous work, here we screened a panel of 245 chemically-diverse small molecules for anti-parasitic activity against Haemonchus contortus-an economically important parasitic nematode of livestock. This panel was screened in vitro against exsheathed third-stage larvae (xL3) of H. contortus using an established phenotypic assay, and the potency of select compounds to inhibit larval motility and development assessed in dose-response assays. Of the 245 compounds screened, three-designated MPK18, MPK334 and YAK308-induced non-wildtype larval phenotypes and repeatedly inhibited xL3-motility, with IC50 values of 45.2 µM, 17.1 µM and 52.7 µM, respectively; two also inhibited larval development, with IC50 values of 12.3 µM (MPK334) and 6.5 µM (YAK308), and none of the three was toxic to human liver cells (HepG2). These findings suggest that these compounds deserve further evaluation as nematocidal candidates. Future work should focus on structure-activity relationship (SAR) studies of these chemical scaffolds, and assess the in vitro and in vivo efficacies and safety of optimised compounds against adults of H. contortus.


Assuntos
Haemonchus/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Haemonchus/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Fenótipo , Bibliotecas de Moléculas Pequenas/química
12.
Molecules ; 26(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34641389

RESUMO

Widespread resistance in parasitic nematodes to most classes of anthelmintic drugs demands the discovery and development of novel compounds with distinct mechanisms of action to complement strategic or integrated parasite control programs. Products from nature-which assume a diverse 'chemical space'-have significant potential as a source of anthelmintic compounds. In the present study, we screened a collection of extracts (n = 7616) derived from marine invertebrates sampled from Australian waters in a high throughput bioassay for in vitro anti-parasitic activity against the barber's pole worm (Haemonchus contortus)-an economically important parasitic nematode of livestock animals. In this high throughput screen (HTS), we identified 58 active extracts that reduced larval motility by ≥70% (at 90 h), equating to an overall 'hit rate' of ~0.8%. Of these 58 extracts, 16 also inhibited larval development by ≥80% (at 168 h) and/or induced 'non-wild-type' (abnormal) larval phenotypes with reference to 'wild-type' (normal) larvae not exposed to extract (negative controls). Most active extracts (54 of 58) originated from sponges, three from chordates (tunicates) and one from a coral; these extracts represented 37 distinct species/taxa of 23 families. An analysis of samples by 1H NMR fingerprinting was utilised to dereplicate hits and to prioritise a set of 29 sponge samples for future chemical investigation. Overall, these results indicate that a range of sponge species from Australian waters represents a rich source of natural compounds with nematocidal or nematostatic properties. Our plan now is to focus on in-depth chemical investigations of the sample set prioritised herein.


Assuntos
Anti-Helmínticos/farmacologia , Hemoncose/tratamento farmacológico , Haemonchus/crescimento & desenvolvimento , Poríferos/química , Extratos de Tecidos/farmacologia , Animais , Anti-Helmínticos/isolamento & purificação , Hemoncose/parasitologia , Haemonchus/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Extratos de Tecidos/isolamento & purificação
13.
Molecules ; 25(8)2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32344703

RESUMO

Kava extract, an aqueous rhizome emulsion of the plant Piper methysticum, has been used for centuries by Pacific Islanders as a ceremonial beverage, and has been sold as an anxiolytic agent for some decades. Kavalactones are a major constituent of kava extract. In a previous investigation, we had identified three kavalactones that inhibit larval development of Haemonchus contortus in an in vitro-bioassay. In the present study, we synthesized two kavalactones, desmethoxyyangonin and yangonin, as well as 17 analogues thereof, and evaluated their anthelmintic activities using the same bioassay as employed previously. Structure activity relationship (SAR) studies showed that a 4-substituent on the pendant aryl ring was required for activity. In particular, compounds with 4-trifluoromethoxy, 4-difluoromethoxy, 4-phenoxy, and 4-N-morpholine substitutions had anthelmintic activities (IC50 values in the range of 1.9 to 8.9 µM) that were greater than either of the parent natural products-desmethoxyyangonin (IC50 of 37.1 µM) and yangonin (IC50 of 15.0 µM). The synthesized analogues did not exhibit toxicity on HepG2 human hepatoma cells in vitro at concentrations of up to 40 µM. These findings confirm the previously-identified kavalactone scaffold as a promising chemotype for new anthelmintics and provide a basis for a detailed SAR investigation focused on developing a novel anthelmintic agent.


Assuntos
Anti-Helmínticos/síntese química , Anti-Helmínticos/farmacologia , Haemonchus/efeitos dos fármacos , Kava/química , Animais , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Estrutura Molecular , Testes de Sensibilidade Parasitária
14.
BMC Bioinformatics ; 19(Suppl 13): 377, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717665

RESUMO

BACKGROUND: Estimating the parameters that describe the ecology of viruses,particularly those that are novel, can be made possible using metagenomic approaches. However, the best-performing existing methods require databases to first estimate an average genome length of a viral community before being able to estimate other parameters, such as viral richness. Although this approach has been widely used, it can adversely skew results since the majority of viruses are yet to be catalogued in databases. RESULTS: In this paper, we present ENVirT, a method for estimating the richness of novel viral mixtures, and for the first time we also show that it is possible to simultaneously estimate the average genome length without a priori information. This is shown to be a significant improvement over database-dependent methods, since we can now robustly analyze samples that may include novel viral types under-represented in current databases. We demonstrate that the viral richness estimates produced by ENVirT are several orders of magnitude higher in accuracy than the estimates produced by existing methods named PHACCS and CatchAll when benchmarked against simulated data. We repeated the analysis of 20 metavirome samples using ENVirT, which produced results in close agreement with complementary in virto analyses. CONCLUSIONS: These insights were previously not captured by existing computational methods. As such, ENVirT is shown to be an essential tool for enhancing our understanding of novel viral populations.


Assuntos
Algoritmos , Fenômenos Ecológicos e Ambientais , Metagenômica , Simulação por Computador , Alimentos Fermentados , Microbioma Gastrointestinal , Genoma Viral , Humanos , Lagos/virologia , Fatores de Tempo , Vírus/genética
15.
Blood ; 129(11): e26-e37, 2017 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-28122742

RESUMO

Drug sensitivity and resistance testing on diagnostic leukemia samples should provide important functional information to guide actionable target and biomarker discovery. We provide proof of concept data by profiling 60 drugs on 68 acute lymphoblastic leukemia (ALL) samples mostly from resistant disease in cocultures of bone marrow stromal cells. Patient-derived xenografts retained the original pattern of mutations found in the matched patient material. Stromal coculture did not prevent leukemia cell cycle activity, but a specific sensitivity profile to cell cycle-related drugs identified samples with higher cell proliferation both in vitro and in vivo as leukemia xenografts. In patients with refractory relapses, individual patterns of marked drug resistance and exceptional responses to new agents of immediate clinical relevance were detected. The BCL2-inhibitor venetoclax was highly active below 10 nM in B-cell precursor ALL (BCP-ALL) subsets, including MLL-AF4 and TCF3-HLF ALL, and in some T-cell ALLs (T-ALLs), predicting in vivo activity as a single agent and in combination with dexamethasone and vincristine. Unexpected sensitivity to dasatinib with half maximal inhibitory concentration values below 20 nM was detected in 2 independent T-ALL cohorts, which correlated with similar cytotoxic activity of the SRC inhibitor KX2-391 and inhibition of SRC phosphorylation. A patient with refractory T-ALL was treated with dasatinib on the basis of drug profiling information and achieved a 5-month remission. Thus, drug profiling captures disease-relevant features and unexpected sensitivity to relevant drugs, which warrants further exploration of this functional assay in the context of clinical trials to develop drug repurposing strategies for patients with urgent medical needs.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Células Cultivadas , Técnicas de Cocultura , Xenoenxertos , Humanos , Células-Tronco Mesenquimais/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia
17.
Mar Drugs ; 17(11)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652835

RESUMO

There is an urgent need to discover and develop new anthelmintics for the treatment of parasitic nematodes of veterinary importance to circumvent challenges linked to drug resistant parasites. Being one of the most diverse natural ecosystems, the marine environment represents a rich resource of novel chemical entities. This study investigated 2000 extracts from marine invertebrates, collected from Australian waters, for anthelmintic activity. Using a well-established in vitro bioassay, these extracts were screened for nematocidal activity against Haemonchus contortus-a socioeconomically important parasitic nematode of livestock animals. Extracts (designated Mu-1, Ha-1 and Ha-2) from two marine sponges (Monanchora unguiculata and Haliclona sp.) each significantly affected larvae of H. contortus. Individual extracts displayed a dose-dependent inhibition of both the motility of exsheathed third-stage larvae (xL3s) and the development of xL3s to fourth-stage larvae (L4s). Active fractions in each of the three extracts were identified using bioassay-guided fractionation. From the active fractions from Monanchora unguiculata, a known pentacyclic guanidine alkaloid, fromiamycalin (1), was purified. This alkaloid was shown to be a moderately potent inhibitor of L4 development (half-maximum inhibitory concentration (IC50) = 26.6 ± 0.74 µM) and L4 motility (IC50 = 39.4 ± 4.83 µM), although it had a relatively low potency at inhibiting of xL3 motility (IC50 ≥ 100 µM). Investigation of the active fractions from the two Haliclona collections led to identification of a mixture of amino alcohol lipids, and, subsequently, a known natural product halaminol A (5). Anthelmintic profiling showed that 5 had limited potency at inhibiting larval development and motility. These data indicate that fromiamycalin, other related pentacyclic guanidine alkaloids and/or halaminols could have potential as anthelmintics following future medicinal chemistry efforts.


Assuntos
Alcaloides/farmacologia , Anti-Helmínticos/farmacologia , Haemonchus/efeitos dos fármacos , Alcaloides/química , Animais , Anti-Helmínticos/química , Austrália , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Poríferos/química , Ratos
18.
FASEB J ; 31(10): 4515-4532, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28687609

RESUMO

As a result of limited classes of anthelmintics and an over-reliance on chemical control, there is a great need to discover new compounds to combat drug resistance in parasitic nematodes. Here, we show that deguelin, a plant-derived rotenoid, selectively and potently inhibits the motility and development of nematodes, which supports its potential as a lead candidate for drug development. Furthermore, we demonstrate that deguelin treatment significantly increases gene transcription that is associated with energy metabolism, particularly oxidative phosphorylation and mitoribosomal protein production before inhibiting motility. Mitochondrial tracking confirmed enhanced oxidative phosphorylation. In accordance, real-time measurements of oxidative phosphorylation in response to deguelin treatment demonstrated an immediate decrease in oxygen consumption in both parasitic (Haemonchus contortus) and free-living (Caenorhabditis elegans) nematodes. Consequently, we hypothesize that deguelin is exerting its toxic effect on nematodes as a modulator of oxidative phosphorylation. This study highlights the dynamic biologic response of multicellular organisms to deguelin perturbation.-Preston, S., Korhonen, P. K., Mouchiroud, L., Cornaglia, M., McGee, S. L., Young, N. D., Davis, R. A., Crawford, S., Nowell, C., Ansell, B. R. E., Fisher, G. M., Andrews, K. T., Chang, B. C. H., Gijs, M. A. M., Sternberg, P. W., Auwerx, J., Baell, J., Hofmann, A., Jabbar, A., Gasser, R. B. Deguelin exerts potent nematocidal activity via the mitochondrial respiratory chain.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Rotenona/análogos & derivados , Animais , Anti-Helmínticos/farmacologia , Caenorhabditis elegans/genética , Resistência a Medicamentos/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Rotenona/farmacologia
20.
J Pathol ; 243(2): 176-192, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28696069

RESUMO

This study investigated hepatitis B virus (HBV) single-nucleotide variants (SNVs) and deletion mutations linked with hepatocellular carcinoma (HCC). Ninety-three HCC patients and 108 non-HCC patients were enrolled for HBV genome-wide next-generation sequencing (NGS) analysis. A systematic literature review and a meta-analysis were performed to validate NGS-defined HCC-associated SNVs and deletions. The experimental results identified 60 NGS-defined HCC-associated SNVs, including 41 novel SNVs, and their pathogenic frequencies. Each SNV was specific for either genotype B (n = 24) or genotype C (n = 34), except for nt53C, which was present in both genotypes. The pathogenic frequencies of these HCC-associated SNVs showed a distinct U-shaped distribution pattern. According to the meta-analysis and literature review, 167 HBV variants from 109 publications were categorized into four levels (A-D) of supporting evidence that they are associated with HCC. The proportion of NGS-defined HCC-associated SNVs among these HBV variants declined significantly from 75% of 12 HCC-associated variants by meta-analysis (Level A) to 0% of 10 HCC-unassociated variants by meta-analysis (Level D) (P < 0.0001). PreS deletions were significantly associated with HCC, in terms of deletion index, for both genotypes B (P = 0.030) and C (P = 0.049). For genotype C, preS deletions involving a specific fragment (nt2977-3013) were significantly associated with HCC (HCC versus non-HCC, 6/34 versus 0/32, P = 0.025). Meta-analysis of preS deletions showed significant association with HCC (summary odds ratio 3.0; 95% confidence interval 2.3-3.9). Transfection of Huh7 cells showed that all of the five novel NGS-defined HCC-associated SNVs in the small surface region influenced hepatocarcinogenesis pathways, including endoplasmic reticulum-stress and DNA repair systems, as shown by microarray, real-time polymerase chain reaction and western blot analysis. Their carcinogenic mechanisms are worthy of further research. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Carcinoma Hepatocelular/genética , Deleção de Genes , Genoma Viral/genética , Vírus da Hepatite B/genética , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único/genética , Reparo do DNA/genética , Estresse do Retículo Endoplasmático/genética , Hepatite B Crônica/genética , Humanos , Proteínas de Neoplasias/genética , Estudos Retrospectivos
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