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1.
Cell ; 176(1-2): 98-112.e14, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30633912

RESUMO

The ability of circulating tumor cells (CTCs) to form clusters has been linked to increased metastatic potential. Yet biological features and vulnerabilities of CTC clusters remain largely unknown. Here, we profile the DNA methylation landscape of single CTCs and CTC clusters from breast cancer patients and mouse models on a genome-wide scale. We find that binding sites for stemness- and proliferation-associated transcription factors are specifically hypomethylated in CTC clusters, including binding sites for OCT4, NANOG, SOX2, and SIN3A, paralleling embryonic stem cell biology. Among 2,486 FDA-approved compounds, we identify Na+/K+ ATPase inhibitors that enable the dissociation of CTC clusters into single cells, leading to DNA methylation remodeling at critical sites and metastasis suppression. Thus, our results link CTC clustering to specific changes in DNA methylation that promote stemness and metastasis and point to cluster-targeting compounds to suppress the spread of cancer.


Assuntos
Neoplasias da Mama/genética , Metástase Neoplásica/genética , Células Neoplásicas Circulantes/patologia , Animais , Neoplasias da Mama/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA/fisiologia , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Proteína Homeobox Nanog/metabolismo , Metástase Neoplásica/fisiopatologia , Células Neoplásicas Circulantes/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Complexo Correpressor Histona Desacetilase e Sin3
2.
Cell ; 169(4): 736-749.e18, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28475899

RESUMO

Immune cells in the tumor microenvironment modulate cancer progression and are attractive therapeutic targets. Macrophages and T cells are key components of the microenvironment, yet their phenotypes and relationships in this ecosystem and to clinical outcomes are ill defined. We used mass cytometry with extensive antibody panels to perform in-depth immune profiling of samples from 73 clear cell renal cell carcinoma (ccRCC) patients and five healthy controls. In 3.5 million measured cells, we identified 17 tumor-associated macrophage phenotypes, 22 T cell phenotypes, and a distinct immune composition correlated with progression-free survival, thereby presenting an in-depth human atlas of the immune tumor microenvironment in this disease. This study revealed potential biomarkers and targets for immunotherapy development and validated tools that can be used for immune profiling of other tumor types.


Assuntos
Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Microambiente Tumoral , Humanos , Citometria por Imagem , Tolerância Imunológica , Rim/citologia , Macrófagos/imunologia , Macrófagos/patologia , Análise de Célula Única , Linfócitos T/imunologia , Linfócitos T/patologia
3.
EMBO J ; 41(24): e111132, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36345783

RESUMO

The cerebral cortex contains billions of neurons, and their disorganization or misspecification leads to neurodevelopmental disorders. Understanding how the plethora of projection neuron subtypes are generated by cortical neural stem cells (NSCs) is a major challenge. Here, we focused on elucidating the transcriptional landscape of murine embryonic NSCs, basal progenitors (BPs), and newborn neurons (NBNs) throughout cortical development. We uncover dynamic shifts in transcriptional space over time and heterogeneity within each progenitor population. We identified signature hallmarks of NSC, BP, and NBN clusters and predict active transcriptional nodes and networks that contribute to neural fate specification. We find that the expression of receptors, ligands, and downstream pathway components is highly dynamic over time and throughout the lineage implying differential responsiveness to signals. Thus, we provide an expansive compendium of gene expression during cortical development that will be an invaluable resource for studying neural developmental processes and neurodevelopmental disorders.


Assuntos
Células-Tronco Neurais , Neurônios , Animais , Camundongos , Diferenciação Celular , Linhagem da Célula/genética , Córtex Cerebral , Células-Tronco Embrionárias , Neurogênese/genética , Neurônios/metabolismo
4.
Nature ; 566(7745): 553-557, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30728496

RESUMO

A better understanding of the features that define the interaction between cancer cells and immune cells is important for the development of new cancer therapies1. However, focus is often given to interactions that occur within the primary tumour and its microenvironment, whereas the role of immune cells during cancer dissemination in patients remains largely uncharacterized2,3. Circulating tumour cells (CTCs) are precursors of metastasis in several types of cancer4-6, and are occasionally found within the bloodstream in association with non-malignant cells such as white blood cells (WBCs)7,8. The identity and function of these CTC-associated WBCs, as well as the molecular features that define the interaction between WBCs and CTCs, are unknown. Here we isolate and characterize individual CTC-associated WBCs, as well as corresponding cancer cells within each CTC-WBC cluster, from patients with breast cancer and from mouse models. We use single-cell RNA sequencing to show that in the majority of these cases, CTCs were associated with neutrophils. When comparing the transcriptome profiles of CTCs associated with neutrophils against those of CTCs alone, we detect a number of differentially expressed genes that outline cell cycle progression, leading to more efficient metastasis formation. Further, we identify cell-cell junction and cytokine-receptor pairs that define CTC-neutrophil clusters, representing key vulnerabilities of the metastatic process. Thus, the association between neutrophils and CTCs drives cell cycle progression within the bloodstream and expands the metastatic potential of CTCs, providing a rationale for targeting this interaction in treatment of breast cancer.


Assuntos
Neoplasias da Mama/patologia , Ciclo Celular , Metástase Neoplásica/patologia , Células Neoplásicas Circulantes/patologia , Neutrófilos/patologia , Animais , Neoplasias da Mama/terapia , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Éxons/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Junções Intercelulares , Camundongos , Mutação/genética , Metástase Neoplásica/genética , Células Neoplásicas Circulantes/metabolismo , Neutrófilos/metabolismo , Análise de Sequência de RNA , Sequenciamento do Exoma
5.
Bioinformatics ; 39(5)2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37220897

RESUMO

SUMMARY: Recently, CITE-seq emerged as a multimodal single-cell technology capturing gene expression and surface protein information from the same single cells, which allows unprecedented insights into disease mechanisms and heterogeneity, as well as immune cell profiling. Multiple single-cell profiling methods exist, but they are typically focused on either gene expression or antibody analysis, not their combination. Moreover, existing software suites are not easily scalable to a multitude of samples. To this end, we designed gExcite, a start-to-end workflow that provides both gene and antibody expression analysis, as well as hashing deconvolution. Embedded in the Snakemake workflow manager, gExcite facilitates reproducible and scalable analyses. We showcase the output of gExcite on a study of different dissociation protocols on PBMC samples. AVAILABILITY AND IMPLEMENTATION: gExcite is open source available on github at https://github.com/ETH-NEXUS/gExcite_pipeline. The software is distributed under the GNU General Public License 3 (GPL3).


Assuntos
Leucócitos Mononucleares , Software , Fluxo de Trabalho , Expressão Gênica , Análise de Célula Única
6.
J Mammary Gland Biol Neoplasia ; 28(1): 26, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066300

RESUMO

Metastasis is the leading cause of cancer-related deaths of breast cancer patients. Some cancer cells in a tumour go through successive steps, referred to as the metastatic cascade, and give rise to metastases at a distant site. We know that the plasticity and heterogeneity of cancer cells play critical roles in metastasis but the precise underlying molecular mechanisms remain elusive. Here we aimed to identify molecular mechanisms of metastasis during colonization, one of the most important yet poorly understood steps of the cascade. We performed single-cell RNA-Seq (scRNA-Seq) on tumours and matched lung macrometastases of patient-derived xenografts of breast cancer. After correcting for confounding factors such as the cell cycle and the percentage of detected genes (PDG), we identified cells in three states in both tumours and metastases. Gene-set enrichment analysis revealed biological processes specific to proliferation and invasion in two states. Our findings suggest that these states are a balance between epithelial-to-mesenchymal (EMT) and mesenchymal-to-epithelial transitions (MET) traits that results in so-called partial EMT phenotypes. Analysis of the top differentially expressed genes (DEGs) between these cell states revealed a common set of partial EMT transcription factors (TFs) controlling gene expression, including ZNF750, OVOL2, TP63, TFAP2C and HEY2. Our data suggest that the TFs related to EMT delineate different cell states in tumours and metastases. The results highlight the marked interpatient heterogeneity of breast cancer but identify common features of single cells from five models of metastatic breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal/genética , Linhagem Celular Tumoral , Fatores de Transcrição , Análise de Célula Única , Proteínas Supressoras de Tumor
7.
Blood ; 137(16): 2139-2151, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33667305

RESUMO

We studied a subset of hematopoietic stem cells (HSCs) that are defined by elevated expression of CD41 (CD41hi) and showed bias for differentiation toward megakaryocytes (Mks). Mouse models of myeloproliferative neoplasms (MPNs) expressing JAK2-V617F (VF) displayed increased frequencies and percentages of the CD41hi vs CD41lo HSCs compared with wild-type controls. An increase in CD41hi HSCs that correlated with JAK2-V617F mutant allele burden was also found in bone marrow from patients with MPN. CD41hi HSCs produced a higher number of Mk-colonies of HSCs in single-cell cultures in vitro, but showed reduced long-term reconstitution potential compared with CD41lo HSCs in competitive transplantations in vivo. RNA expression profiling showed an upregulated cell cycle, Myc, and oxidative phosphorylation gene signatures in CD41hi HSCs, whereas CD41lo HSCs showed higher gene expression of interferon and the JAK/STAT and TNFα/NFκB signaling pathways. Higher cell cycle activity and elevated levels of reactive oxygen species were confirmed in CD41hi HSCs by flow cytometry. Expression of Epcr, a marker for quiescent HSCs inversely correlated with expression of CD41 in mice, but did not show such reciprocal expression pattern in patients with MPN. Treatment with interferon-α further increased the frequency and percentage of CD41hi HSCs and reduced the number of JAK2-V617F+ HSCs in mice and patients with MPN. The shift toward the CD41hi subset of HSCs by interferon-α provides a possible mechanism of how interferon-α preferentially targets the JAK2 mutant clone.


Assuntos
Interferon-alfa/uso terapêutico , Janus Quinase 2/genética , Megacariócitos/metabolismo , Transtornos Mieloproliferativos/genética , Animais , Técnicas de Introdução de Genes , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Megacariócitos/citologia , Camundongos , Camundongos Transgênicos , Transtornos Mieloproliferativos/tratamento farmacológico , Glicoproteína IIb da Membrana de Plaquetas/genética , Mutação Puntual/efeitos dos fármacos
8.
BMC Genomics ; 23(1): 289, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35410128

RESUMO

BACKGROUND: The continued spread of SARS-CoV-2 and emergence of new variants with higher transmission rates and/or partial resistance to vaccines has further highlighted the need for large-scale testing and genomic surveillance. However, current diagnostic testing (e.g., PCR) and genomic surveillance methods (e.g., whole genome sequencing) are performed separately, thus limiting the detection and tracing of SARS-CoV-2 and emerging variants. RESULTS: Here, we developed DeepSARS, a high-throughput platform for simultaneous diagnostic detection and genomic surveillance of SARS-CoV-2 by the integration of molecular barcoding, targeted deep sequencing, and computational phylogenetics. DeepSARS enables highly sensitive viral detection, while also capturing genomic diversity and viral evolution. We show that DeepSARS can be rapidly adapted for identification of emerging variants, such as alpha, beta, gamma, and delta strains, and profile mutational changes at the population level. CONCLUSIONS: DeepSARS sets the foundation for quantitative diagnostics that capture viral evolution and diversity. DeepSARS uses molecular barcodes (BCs) and multiplexed targeted deep sequencing (NGS) to enable simultaneous diagnostic detection and genomic surveillance of SARS-CoV-2. Image was created using Biorender.com .


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Genômica , Humanos , Mutação , SARS-CoV-2/genética , Sequenciamento Completo do Genoma
9.
J Clin Microbiol ; 60(3): e0236221, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35170980

RESUMO

Treatment of multidrug-resistant or rifampicin-resistant tuberculosis (MDR/RR-TB), although improved in recent years with shorter, more tolerable regimens, remains largely standardized and based on limited drug susceptibility testing (DST). More individualized treatment with expanded DST access is likely to improve patient outcomes. To assess the potential of TB drug resistance prediction based on whole-genome sequencing (WGS) to provide more effective treatment regimens, we applied current South African treatment recommendations to a retrospective cohort of MDR/RR-TB patients from Khayelitsha, Cape Town. Routine DST and clinical data were used to retrospectively categorize patients into a recommended regimen, either a standardized short regimen or a longer individualized regimen. Potential regimen changes were then described with the addition of WGS-derived DST. WGS data were available for 1274 MDR/RR-TB patient treatment episodes across 2008 to 2017. Among 834 patients initially eligible for the shorter regimen, 385 (46%) may have benefited from reduced drug dosage or removing ineffective drugs when WGS data were considered. A further 187 (22%) patients may have benefited from more effective adjusted regimens. Among 440 patients initially eligible for a longer individualized regimen, 153 (35%) could have been switched to the short regimen. Overall, 305 (24%) patients had MDR/RR-TB with second-line TB drug resistance, where the availability of WGS-derived DST would have allowed more effective treatment individualization. These data suggest considerable benefits could accrue from routine access to WGS-derived resistance prediction. Advances in culture-free sequencing and expansion of the reference resistance mutation catalogue will increase the utility of WGS resistance prediction.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Estudos de Coortes , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Estudos Retrospectivos , Rifampina/farmacologia , Rifampina/uso terapêutico , África do Sul , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
10.
Mol Phylogenet Evol ; 166: 107296, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34438051

RESUMO

Free-living flatworms of the genus Macrostomum are small and transparent animals, representing attractive study organisms for a broad range of topics in evolutionary, developmental, and molecular biology. The genus includes the model organism M. lignano for which extensive molecular resources are available, and recently there is a growing interest in extending work to additional species in the genus. These endeavours are currently hindered because, even though >200 Macrostomum species have been taxonomically described, molecular phylogenetic information and geographic sampling remain limited. We report on a global sampling campaign aimed at increasing taxon sampling and geographic representation of the genus. Specifically, we use extensive transcriptome and single-locus data to generate phylogenomic hypotheses including 145 species. Across different phylogenetic methods and alignments used, we identify several consistent clades, while their exact grouping is less clear, possibly due to a radiation early in Macrostomum evolution. Moreover, we uncover a large undescribed diversity, with 94 of the studied species likely being new to science, and we identify multiple novel morphological traits. Furthermore, we identify cryptic speciation in a taxonomically challenging assemblage of species, suggesting that the use of molecular markers is a prerequisite for future work, and we describe the distribution of putative synapomorphies and suggest taxonomic revisions based on our finding. Our large-scale phylogenomic dataset now provides a robust foundation for comparative analyses of morphological, behavioural and molecular evolution in this genus.


Assuntos
Platelmintos , Animais , Evolução Molecular , Fenótipo , Filogenia , Platelmintos/genética , Transcriptoma
11.
Blood ; 135(18): 1548-1559, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32181816

RESUMO

Clonal hematopoiesis (CH) is associated with age and an increased risk of myeloid malignancies, cardiovascular risk, and all-cause mortality. We tested for CH in a setting where hematopoietic stem cells (HSCs) of the same individual are exposed to different degrees of proliferative stress and environments, ie, in long-term survivors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and their respective related donors (n = 42 donor-recipient pairs). With a median follow-up time since allo-HSCT of 16 years (range, 10-32 years), we found a total of 35 mutations in 23 out of 84 (27.4%) study participants. Ten out of 42 donors (23.8%) and 13 out of 42 recipients (31%) had CH. CH was associated with older donor and recipient age. We identified 5 cases of donor-engrafted CH, with 1 case progressing into myelodysplastic syndrome in both donor and recipient. Four out of 5 cases showed increased clone size in recipients compared with donors. We further characterized the hematopoietic system in individuals with CH as follows: (1) CH was consistently present in myeloid cells but varied in penetrance in B and T cells; (2) colony-forming units (CFUs) revealed clonal evolution or multiple independent clones in individuals with multiple CH mutations; and (3) telomere shortening determined in granulocytes suggested ∼20 years of added proliferative history of HSCs in recipients compared with their donors, with telomere length in CH vs non-CH CFUs showing varying patterns. This study provides insight into the long-term behavior of the same human HSCs and respective CH development under different proliferative conditions.


Assuntos
Hematopoiese Clonal , Transplante de Células-Tronco Hematopoéticas/mortalidade , Células-Tronco Hematopoéticas/metabolismo , Doadores de Tecidos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Evolução Clonal/genética , Ensaio de Unidades Formadoras de Colônias , Análise Mutacional de DNA , Feminino , Células-Tronco Hematopoéticas/citologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Telômero , Transplantados , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
12.
PLoS Comput Biol ; 17(12): e1009036, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34910733

RESUMO

Tumour progression is an evolutionary process in which different clones evolve over time, leading to intra-tumour heterogeneity. Interactions between clones can affect tumour evolution and hence disease progression and treatment outcome. Intra-tumoural pairs of mutations that are overrepresented in a co-occurring or clonally exclusive fashion over a cohort of patient samples may be suggestive of a synergistic effect between the different clones carrying these mutations. We therefore developed a novel statistical testing framework, called GeneAccord, to identify such gene pairs that are altered in distinct subclones of the same tumour. We analysed our framework for calibration and power. By comparing its performance to baseline methods, we demonstrate that to control type I errors, it is essential to account for the evolutionary dependencies among clones. In applying GeneAccord to the single-cell sequencing of a cohort of 123 acute myeloid leukaemia patients, we find 1 clonally co-occurring and 8 clonally exclusive gene pairs. The clonally exclusive pairs mostly involve genes of the key signalling pathways.


Assuntos
Biologia Computacional/métodos , Leucemia Mieloide Aguda , Algoritmos , Progressão da Doença , Humanos , Leucemia Mieloide Aguda/classificação , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Modelos Estatísticos , Mutação/genética , Transdução de Sinais/genética
13.
Antimicrob Agents Chemother ; 65(9): e0050421, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34228548

RESUMO

Antimicrobial resistance (AMR) poses a threat to global health and the economy. Rifampicin-resistant Mycobacterium tuberculosis accounts for a third of the global AMR burden. Gaining the upper hand on AMR requires a deeper understanding of the physiology of resistance. AMR often results in a fitness cost in the absence of drug. Identifying the molecular mechanisms underpinning this cost could help strengthen future treatment regimens. Here, we used a collection of M. tuberculosis strains that provide an evolutionary and phylogenetic snapshot of rifampicin resistance and subjected them to genome-wide transcriptomic and proteomic profiling to identify key perturbations of normal physiology. We found that the clinically most common rifampicin resistance-conferring mutation, RpoB Ser450Leu, imparts considerable gene expression changes, many of which are mitigated by the compensatory mutation in RpoC Leu516Pro. However, our data also provide evidence for pervasive epistasis-the same resistance mutation imposed a different fitness cost and functionally distinct changes to gene expression in genetically unrelated clinical strains. Finally, we report a likely posttranscriptional modulation of gene expression that is shared in most of the tested strains carrying RpoB Ser450Leu, resulting in an increased abundance of proteins involved in central carbon metabolism. These changes contribute to a more general trend in which the disruption of the composition of the proteome correlates with the fitness cost of the RpoB Ser450Leu mutation in different strains.


Assuntos
RNA Polimerases Dirigidas por DNA , Mycobacterium tuberculosis , Proteínas de Bactérias/genética , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Filogenia , Proteômica , Rifampina/farmacologia
14.
EMBO J ; 36(24): 3619-3633, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29030486

RESUMO

Single-cell RNA sequencing is a powerful technology for assessing heterogeneity within defined cell populations. Here, we describe the heterogeneity of a B220+CD117intCD19-NK1.1- uncommitted hematopoietic progenitor having combined lymphoid and myeloid potential. Phenotypic and functional assays revealed four subpopulations within the progenitor with distinct lineage developmental potentials. Among them, the Ly6D+SiglecH-CD11c- fraction was lymphoid-restricted exhibiting strong B-cell potential, whereas the Ly6D-SiglecH-CD11c- fraction showed mixed lympho-myeloid potential. Single-cell RNA sequencing of these subsets revealed that the latter population comprised a mixture of cells with distinct lymphoid and myeloid transcriptional signatures and identified a subgroup as the potential precursor of Ly6D+SiglecH-CD11c- Subsequent functional assays confirmed that B220+CD117intCD19-NK1.1- single cells are, with rare exceptions, not bipotent for lymphoid and myeloid lineages. A B-cell priming gradient was observed within the Ly6D+SiglecH-CD11c- subset and we propose a herein newly identified subgroup as the direct precursor of the first B-cell committed stage. Therefore, the apparent multipotency of B220+CD117intCD19-NK1.1- progenitors results from underlying heterogeneity at the single-cell level and highlights the validity of single-cell transcriptomics for resolving cellular heterogeneity and developmental relationships among hematopoietic progenitors.


Assuntos
Células-Tronco Hematopoéticas/fisiologia , Análise de Sequência de RNA/métodos , Animais , Linfócitos B/citologia , Linfócitos B/fisiologia , Diferenciação Celular , Linhagem da Célula , Feminino , Perfilação da Expressão Gênica , Heterogeneidade Genética , Células-Tronco Hematopoéticas/citologia , Sequenciamento de Nucleotídeos em Larga Escala , Células Progenitoras Linfoides/citologia , Células Progenitoras Linfoides/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Células Progenitoras Mieloides/citologia , Células Progenitoras Mieloides/fisiologia , Análise de Célula Única
15.
Blood ; 134(21): 1832-1846, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31511238

RESUMO

Increased energy requirement and metabolic reprogramming are hallmarks of cancer cells. We show that metabolic alterations in hematopoietic cells are fundamental to the pathogenesis of mutant JAK2-driven myeloproliferative neoplasms (MPNs). We found that expression of mutant JAK2 augmented and subverted metabolic activity of MPN cells, resulting in systemic metabolic changes in vivo, including hypoglycemia, adipose tissue atrophy, and early mortality. Hypoglycemia in MPN mouse models correlated with hyperactive erythropoiesis and was due to a combination of elevated glycolysis and increased oxidative phosphorylation. Modulating nutrient supply through high-fat diet improved survival, whereas high-glucose diet augmented the MPN phenotype. Transcriptomic and metabolomic analyses identified numerous metabolic nodes in JAK2-mutant hematopoietic stem and progenitor cells that were altered in comparison with wild-type controls. We studied the consequences of elevated levels of Pfkfb3, a key regulatory enzyme of glycolysis, and found that pharmacological inhibition of Pfkfb3 with the small molecule 3PO reversed hypoglycemia and reduced hematopoietic manifestations of MPNs. These effects were additive with the JAK1/2 inhibitor ruxolitinib in vivo and in vitro. Inhibition of glycolysis by 3PO altered the redox homeostasis, leading to accumulation of reactive oxygen species and augmented apoptosis rate. Our findings reveal the contribution of metabolic alterations to the pathogenesis of MPNs and suggest that metabolic dependencies of mutant cells represent vulnerabilities that can be targeted for treating MPNs.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Animais , Humanos , Camundongos , Mutação
16.
BMC Genomics ; 21(1): 462, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631219

RESUMO

BACKGROUND: The genus Macrostomum consists of small free-living flatworms and contains Macrostomum lignano, which has been used in investigations of ageing, stem cell biology, bioadhesion, karyology, and sexual selection in hermaphrodites. Two types of mating behaviour occur within this genus. Some species, including M. lignano, mate via reciprocal copulation, where, in a single mating, both partners insert their male copulatory organ into the female storage organ and simultaneously donate and receive sperm. Other species mate via hypodermic insemination, where worms use a needle-like copulatory organ to inject sperm into the tissue of the partner. These contrasting mating behaviours are associated with striking differences in sperm and copulatory organ morphology. Here we expand the genomic resources within the genus to representatives of both behaviour types and investigate whether genes vary in their rate of evolution depending on their putative function. RESULTS: We present de novo assembled transcriptomes of three Macrostomum species, namely M. hystrix, a close relative of M. lignano that mates via hypodermic insemination, M. spirale, a more distantly related species that mates via reciprocal copulation, and finally M. pusillum, which represents a clade that is only distantly related to the other three species and also mates via hypodermic insemination. We infer 23,764 sets of homologous genes and annotate them using experimental evidence from M. lignano. Across the genus, we identify 521 gene families with conserved patterns of differential expression between juvenile vs. adult worms and 185 gene families with a putative expression in the testes that are restricted to the two reciprocally mating species. Further, we show that homologs of putative reproduction-related genes have a higher protein divergence across the four species than genes lacking such annotations and that they are more difficult to identify across the four species, indicating that these genes evolve more rapidly, while genes involved in neoblast function are more conserved. CONCLUSIONS: This study improves the genus Macrostomum as a model system, by providing resources for the targeted investigation of gene function in a broad range of species. And we, for the first time, show that reproduction-related genes evolve at an accelerated rate in flatworms.


Assuntos
Evolução Molecular , Platelmintos/genética , Animais , Genes de Helmintos , Proteínas de Helminto/genética , Hibridização In Situ , Filogenia , Platelmintos/anatomia & histologia , Platelmintos/classificação , Platelmintos/crescimento & desenvolvimento , RNA-Seq , Reprodução/genética , Transcriptoma
17.
J Cell Sci ; 131(1)2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29158223

RESUMO

Gene splicing profiles are frequently altered in cancer, and the splice variants of fibronectin (FN) that contain the extra-domains A (EDA) or B (EDB), referred to as EDA+FN or EDB+FN, are highly upregulated in tumor vasculature. Transforming growth factor ß (TGF-ß) signaling has been attributed a pivotal role in glioblastoma, with TGF-ß promoting angiogenesis and vessel remodeling. By using immunohistochemistry staining, we observed that the oncofetal FN isoforms EDA+FN and EDB+FN are expressed in glioblastoma vasculature. Ex vivo single-cell gene expression profiling of tumors by using CD31 and α-smooth muscle actin (αSMA) as markers for endothelial cells, and pericytes and vascular smooth muscle cells (VSMCs), respectively, confirmed the predominant expression of FN, EDA+FN and EDB+FN in the vascular compartment of glioblastoma. Specifically, within the CD31-positive cell population, we identified a positive correlation between the expression of EDA+FN and EDB+FN, and of molecules associated with TGF-ß signaling. Further, TGF-ß induced EDA+FN and EDB+FN in human cerebral microvascular endothelial cells and glioblastoma-derived endothelial cells in a SMAD3- and SMAD4-dependent manner. In turn, we found that FN modulated TGF-ß superfamily signaling in endothelial cells via the EDA and EDB, pointing towards a bidirectional influence of oncofetal FN and TGF-ß superfamily signaling.


Assuntos
Células Endoteliais/metabolismo , Fibronectinas/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/farmacologia , Processamento Alternativo , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Neovascularização Patológica , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética
18.
Nature ; 511(7507): 46-51, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24990743

RESUMO

The large spectrum of limb morphologies reflects the wide evolutionary diversification of the basic pentadactyl pattern in tetrapods. In even-toed ungulates (artiodactyls, including cattle), limbs are adapted for running as a consequence of progressive reduction of their distal skeleton to symmetrical and elongated middle digits with hoofed phalanges. Here we analyse bovine embryos to establish that polarized gene expression is progressively lost during limb development in comparison to the mouse. Notably, the transcriptional upregulation of the Ptch1 gene, which encodes a Sonic hedgehog (SHH) receptor, is disrupted specifically in the bovine limb bud mesenchyme. This is due to evolutionary alteration of a Ptch1 cis-regulatory module, which no longer responds to graded SHH signalling during bovine handplate development. Our study provides a molecular explanation for the loss of digit asymmetry in bovine limb buds and suggests that modifications affecting the Ptch1 cis-regulatory landscape have contributed to evolutionary diversification of artiodactyl limbs.


Assuntos
Evolução Biológica , Extremidades/anatomia & histologia , Extremidades/embriologia , Proteínas Hedgehog/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Padronização Corporal , Bovinos , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Botões de Extremidades/anatomia & histologia , Botões de Extremidades/embriologia , Masculino , Mesoderma/metabolismo , Camundongos , Camundongos Transgênicos , Receptores Patched , Receptor Patched-1 , Receptores de Superfície Celular/genética , Sequências Reguladoras de Ácido Nucleico/genética
19.
Dev Biol ; 433(2): 448-460, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28757111

RESUMO

Temporal and spatial characterization of gene expression is a prerequisite for the understanding of cell-, tissue-, and organ-differentiation. In a multifaceted approach to investigate gene expression in the tail plate of the free-living marine flatworm Macrostomum lignano, we performed a posterior-region-specific in situ hybridization screen, RNA sequencing (RNA-seq) of regenerating animals, and functional analyses of selected tail-specific genes. The in situ screen revealed transcripts expressed in the antrum, cement glands, adhesive organs, prostate glands, rhabdite glands, and other tissues. Next we used RNA-seq to characterize temporal expression in the regenerating tail plate revealing a time restricted onset of both adhesive organs and copulatory apparatus regeneration. In addition, we identified three novel previously unannotated genes solely expressed in the regenerating stylet. RNA interference showed that these genes are required for the formation of not only the stylet but the whole male copulatory apparatus. RNAi treated animals lacked the stylet, vesicula granulorum, seminal vesicle, false seminal vesicle, and prostate glands, while the other tissues of the tail plate, such as adhesive organs regenerated normally. In summary, our findings provide a large resource of expression data during homeostasis and regeneration of the morphologically complex tail regeneration and pave the way for a better understanding of organogenesis in M. lignano.


Assuntos
Regulação da Expressão Gênica , Genes de Helmintos , Proteínas de Helminto/genética , Platelmintos/fisiologia , Regeneração/genética , Cauda/fisiologia , Animais , Proteínas de Helminto/biossíntese , Organismos Hermafroditas , Hibridização In Situ , Microvilosidades , Especificidade de Órgãos , Platelmintos/genética , Interferência de RNA , RNA de Helmintos/biossíntese , RNA de Helmintos/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Regeneração/fisiologia , Transcriptoma , Cicatrização/genética
20.
Bioinformatics ; 34(1): 107-108, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28968639

RESUMO

Motivation: Next-generation sequencing is now an established method in genomics, and massive amounts of sequencing data are being generated on a regular basis. Analysis of the sequencing data is typically performed by lab-specific in-house solutions, but the agreement of results from different facilities is often small. General standards for quality control, reproducibility and documentation are missing. Results: We developed NGS-pipe, a flexible, transparent and easy-to-use framework for the design of pipelines to analyze whole-exome, whole-genome and transcriptome sequencing data. NGS-pipe facilitates the harmonization of genomic data analysis by supporting quality control, documentation, reproducibility, parallelization and easy adaptation to other NGS experiments. Availability and implementation: https://github.com/cbg-ethz/NGS-pipe. Contact: niko.beerenwinkel@bsse.ethz.ch.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Análise de Sequência de RNA/métodos , Software , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/normas , Humanos , Neoplasias/genética , Reprodutibilidade dos Testes , Análise de Sequência de DNA/normas , Análise de Sequência de RNA/normas
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