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1.
Cell ; 186(13): 2765-2782.e28, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37327786

RESUMO

Cancer is characterized by hypomethylation-associated silencing of large chromatin domains, whose contribution to tumorigenesis is uncertain. Through high-resolution genome-wide single-cell DNA methylation sequencing, we identify 40 core domains that are uniformly hypomethylated from the earliest detectable stages of prostate malignancy through metastatic circulating tumor cells (CTCs). Nested among these repressive domains are smaller loci with preserved methylation that escape silencing and are enriched for cell proliferation genes. Transcriptionally silenced genes within the core hypomethylated domains are enriched for immune-related genes; prominent among these is a single gene cluster harboring all five CD1 genes that present lipid antigens to NKT cells and four IFI16-related interferon-inducible genes implicated in innate immunity. The re-expression of CD1 or IFI16 murine orthologs in immuno-competent mice abrogates tumorigenesis, accompanied by the activation of anti-tumor immunity. Thus, early epigenetic changes may shape tumorigenesis, targeting co-located genes within defined chromosomal loci. Hypomethylation domains are detectable in blood specimens enriched for CTCs.


Assuntos
Metilação de DNA , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Carcinogênese/genética , DNA , Epigênese Genética , Neoplasias da Próstata/genética , Células Neoplásicas Circulantes
2.
Cell ; 161(6): 1437-52, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-26046443

RESUMO

Germ cells are vital for transmitting genetic information from one generation to the next and for maintaining the continuation of species. Here, we analyze the transcriptome of human primordial germ cells (PGCs) from the migrating stage to the gonadal stage at single-cell and single-base resolutions. Human PGCs show unique transcription patterns involving the simultaneous expression of both pluripotency genes and germline-specific genes, with a subset of them displaying developmental-stage-specific features. Furthermore, we analyze the DNA methylome of human PGCs and find global demethylation of their genomes. Approximately 10 to 11 weeks after gestation, the PGCs are nearly devoid of any DNA methylation, with only 7.8% and 6.0% of the median methylation levels in male and female PGCs, respectively. Our work paves the way toward deciphering the complex epigenetic reprogramming of the germline with the aim of restoring totipotency in fertilized oocytes.


Assuntos
Metilação de DNA , Células Germinativas/metabolismo , Transcriptoma , Movimento Celular , Cromossomos Humanos X , Análise por Conglomerados , Embrião de Mamíferos/metabolismo , Feminino , Histonas/metabolismo , Humanos , Masculino , Análise de Componente Principal , Fatores de Transcrição SOX/metabolismo
3.
Mol Cell ; 81(19): 4041-4058.e15, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34624217

RESUMO

Deregulation of oncogenic signals in cancer triggers replication stress. Immediate early genes (IEGs) are rapidly and transiently expressed following stressful signals, contributing to an integrated response. Here, we find that the orphan nuclear receptor NR4A1 localizes across the gene body and 3' UTR of IEGs, where it inhibits transcriptional elongation by RNA Pol II, generating R-loops and accessible chromatin domains. Acute replication stress causes immediate dissociation of NR4A1 and a burst of transcriptionally poised IEG expression. Ectopic expression of NR4A1 enhances tumorigenesis by breast cancer cells, while its deletion leads to massive chromosomal instability and proliferative failure, driven by deregulated expression of its IEG target, FOS. Approximately half of breast and other primary cancers exhibit accessible chromatin domains at IEG gene bodies, consistent with this stress-regulatory pathway. Cancers that have retained this mechanism in adapting to oncogenic replication stress may be dependent on NR4A1 for their proliferation.


Assuntos
Neoplasias da Mama/metabolismo , Proliferação de Células , Proteínas Imediatamente Precoces/metabolismo , Mitose , Células Neoplásicas Circulantes/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Regiões 3' não Traduzidas , Animais , Antineoplásicos/farmacologia , Sítios de Ligação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Montagem e Desmontagem da Cromatina , Feminino , Regulação Neoplásica da Expressão Gênica , Instabilidade Genômica , Células HEK293 , Humanos , Proteínas Imediatamente Precoces/genética , Indóis/farmacologia , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos SCID , Mitose/efeitos dos fármacos , Células Neoplásicas Circulantes/efeitos dos fármacos , Células Neoplásicas Circulantes/patologia , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/antagonistas & inibidores , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Fenilacetatos/farmacologia , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Estruturas R-Loop , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Transdução de Sinais , Elongação da Transcrição Genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
N Engl J Med ; 390(16): 1467-1480, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38657244

RESUMO

BACKGROUND: Patients with relapsed or refractory hematologic cancers have a poor prognosis. Chimeric antigen receptor (CAR) T-cell therapy as a bridge to allogeneic hematopoietic stem-cell transplantation (HSCT) has the potential for long-term tumor elimination. However, pre-HSCT myeloablation and graft-versus-host disease (GVHD) prophylaxis agents have toxic effects and could eradicate residual CAR T cells and compromise antitumor effects. Whether the integration of CAR T-cell therapy and allogeneic HSCT can preserve CAR T-cell function and improve tumor control is unclear. METHODS: We tested a novel "all-in-one" strategy consisting of sequential CD7 CAR T-cell therapy and haploidentical HSCT in 10 patients with relapsed or refractory CD7-positive leukemia or lymphoma. After CAR T-cell therapy led to complete remission with incomplete hematologic recovery, patients received haploidentical HSCT without pharmacologic myeloablation or GVHD prophylaxis drugs. Toxic effects and efficacy were closely monitored. RESULTS: After CAR T-cell therapy, all 10 patients had complete remission with incomplete hematologic recovery and grade 4 pancytopenia. After haploidentical HSCT, 1 patient died on day 13 of septic shock and encephalitis, 8 patients had full donor chimerism, and 1 patient had autologous hematopoiesis. Three patients had grade 2 HSCT-associated acute GVHD. The median follow-up was 15.1 months (range, 3.1 to 24.0) after CAR T-cell therapy. Six patients remained in minimal residual disease-negative complete remission, 2 had a relapse of CD7-negative leukemia, and 1 died of septic shock at 3.7 months. The estimated 1-year overall survival was 68% (95% confidence interval [CI], 43 to 100), and the estimated 1-year disease-free survival was 54% (95% CI, 29 to 100). CONCLUSIONS: Our findings suggest that sequential CD7 CAR T-cell therapy and haploidentical HSCT is safe and effective, with remission and serious but reversible adverse events. This strategy offers a feasible approach for patients with CD7-positive tumors who are ineligible for conventional allogeneic HSCT. (Funded by the National Natural Science Foundation of China and the Key Project of Science and Technology Department of Zhejiang Province; ClinicalTrials.gov numbers, NCT04599556 and NCT04538599.).


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Imunoterapia Adotiva , Leucemia , Linfoma , Receptores de Antígenos Quiméricos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antígenos CD7 , Terapia Combinada , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Leucemia/terapia , Leucemia/mortalidade , Linfoma/mortalidade , Linfoma/terapia , Receptores de Antígenos Quiméricos/uso terapêutico , Indução de Remissão , Transplante Homólogo , Recidiva , Idoso
5.
Nature ; 594(7862): 283-288, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33981036

RESUMO

Homologous recombination (HR) repairs DNA double-strand breaks (DSBs) in the S and G2 phases of the cell cycle1-3. Several HR proteins are preferentially recruited to DSBs at transcriptionally active loci4-10, but how transcription promotes HR is poorly understood. Here we develop an assay to assess the effect of local transcription on HR. Using this assay, we find that transcription stimulates HR to a substantial extent. Tethering RNA transcripts to the vicinity of DSBs recapitulates the effects of local transcription, which suggests that transcription enhances HR through RNA transcripts. Tethered RNA transcripts stimulate HR in a sequence- and orientation-dependent manner, indicating that they function by forming DNA-RNA hybrids. In contrast to most HR proteins, RAD51-associated protein 1 (RAD51AP1) only promotes HR when local transcription is active. RAD51AP1 drives the formation of R-loops in vitro and is required for tethered RNAs to stimulate HR in cells. Notably, RAD51AP1 is necessary for the DSB-induced formation of DNA-RNA hybrids in donor DNA, linking R-loops to D-loops. In vitro, RAD51AP1-generated R-loops enhance the RAD51-mediated formation of D-loops locally and give rise to intermediates that we term 'DR-loops', which contain both DNA-DNA and DNA-RNA hybrids and favour RAD51 function. Thus, at DSBs in transcribed regions, RAD51AP1 promotes the invasion of RNA transcripts into donor DNA, and stimulates HR through the formation of DR-loops.


Assuntos
DNA/genética , DNA/metabolismo , Recombinação Homóloga/genética , Estruturas R-Loop/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , DNA/química , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Genes/genética , Genes Reporter/genética , Proteínas de Fluorescência Verde/genética , Humanos , Técnicas In Vitro , RNA Mensageiro/química , Proteínas de Ligação a RNA/metabolismo , Rad51 Recombinase/metabolismo
6.
Proc Natl Acad Sci U S A ; 116(52): 26835-26845, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31843922

RESUMO

Transcriptional profiling has defined pancreatic ductal adenocarcinoma (PDAC) into distinct subtypes with the majority being classical epithelial (E) or quasi-mesenchymal (QM). Despite clear differences in clinical behavior, growing evidence indicates these subtypes exist on a continuum with features of both subtypes present and suggestive of interconverting cell states. Here, we investigated the impact of different therapies being evaluated in PDAC on the phenotypic spectrum of the E/QM state. We demonstrate using RNA-sequencing and RNA-in situ hybridization (RNA-ISH) that FOLFIRINOX combination chemotherapy induces a common shift of both E and QM PDAC toward a more QM state in cell lines and patient tumors. In contrast, Vitamin D, another drug under clinical investigation in PDAC, induces distinct transcriptional responses in each PDAC subtype, with augmentation of the baseline E and QM state. Importantly, this translates to functional changes that increase metastatic propensity in QM PDAC, but decrease dissemination in E PDAC in vivo models. These data exemplify the importance of both the initial E/QM subtype and the plasticity of E/QM states in PDAC in influencing response to therapy, which highlights their relevance in guiding clinical trials.

7.
Hum Reprod ; 36(2): 318-330, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33313772

RESUMO

STUDY QUESTION: Is it possible to evaluate the methylome of individual oocytes to investigate the DNA methylome alterations in metaphase II (MII) oocytes with reduced embryo developmental potential? SUMMARY ANSWER: The DNA methylome of each human first polar body (PB1) closely mirrored that of its sibling MII oocyte; hypermethylated long interspersed nuclear element (LINE) and long terminal repeats (LTRs) and methylation aberrations in PB1 promoter regions may indicate poor embryo development. WHAT IS KNOWN ALREADY: The developmental potential of an embryo is determined by the oocyte's developmental competence, and the PB1 is a good substitute to examine the chromosomal status of the corresponding oocyte. However, DNA methylation, a key epigenetic modification, also regulates gene expression and embryo development. STUDY DESIGN, SIZE, DURATION: Twelve pairs of PB1s and sibling MII oocytes were biopsied and sequenced to compare their methylomes. To further investigate the methylome of PB1s and the potential epigenetic factors that may affect oocyte quality, MII oocytes (n = 74) were fertilized through ICSI, while PB1s were biopsied and profiled to measure DNA methylation. The corresponding embryos were further cultured to track their development potential. The oocytes and sperm samples used in this study were donated by healthy volunteers with signed informed consent. PARTICIPANTS/MATERIALS, SETTING, METHODS: Single-cell methylome sequencing was applied to obtain the DNA methylation profiles of PB1s and oocytes. The DNA methylome of PB1s was compared between the respective group of oocytes that progressed to blastocysts and the group of oocytes that failed to develop. DNA methylation levels of corresponding regions and differentially methylated regions were calculated using customized Perl and R scripts. RNA-seq data were downloaded from a previously published paper and reanalysed. MAIN RESULTS AND THE ROLE OF CHANCE: The results from PB1-MII oocyte pair validated that PB1 contains nearly the same methylome (average Pearson correlation is 0.92) with sibling MII oocyte. LINE and LTR expression increased markedly after fertilization. Moreover, the DNA methylation levels in LINE (including LINE1 and LINE2) and LTR were significantly higher in the PB1s of embryos that could not reach the blastocyst stage (Wilcoxon-Matt-Whitney test, P < 0.05). DNA methylation in PB1 promoters correlated negatively with gene expression of MII oocyte. Regarding the methylation status of the promoter regions, 66 genes were hypermethylated in the developmental arrested group, with their related functions (significantly enriched in several Gene Ontology terms) including transcription, positive regulation of adenylate cyclase activity, mitogen-activated protein kinase (MAPK) cascade and intracellular oestrogen receptor signalling pathway. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Data analysis performed in this study focused on the competence of human oocytes and compared them with maternal genetic and epigenetic profiles. Therefore, data regarding the potential regulatory roles of paternal genomes in embryo development are lacking. WIDER IMPLICATIONS OF THE FINDINGS: The results from PB1-oocyte pairs demonstrated that PB1s shared similar methylomes with their sibling oocytes. The selection of the good embryos for transfer should not only rely on morphology but also consider the DNA methylation of the corresponding PB1 and therefore MII oocyte. The application of early-stage analysis of PB1 offers an option for high-quality oocyte and embryo selection, which provides an additional tool for elective single embryo transfer in assisted reproduction. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Key Research and Development Program of China (2018YFC1004003, 2017YFA0103801), the National Natural Science Foundation of China (81730038, 3187144, 81521002) and the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA16020703). The authors have no conflicts of interest to declare.


Assuntos
Epigenoma , Corpos Polares , China , Desenvolvimento Embrionário/genética , Humanos , Masculino , Oócitos
8.
Nature ; 511(7511): 606-10, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-25079557

RESUMO

DNA methylation is a crucial element in the epigenetic regulation of mammalian embryonic development. However, its dynamic patterns have not been analysed at the genome scale in human pre-implantation embryos due to technical difficulties and the scarcity of required materials. Here we systematically profile the methylome of human early embryos from the zygotic stage through to post-implantation by reduced representation bisulphite sequencing and whole-genome bisulphite sequencing. We show that the major wave of genome-wide demethylation is complete at the 2-cell stage, contrary to previous observations in mice. Moreover, the demethylation of the paternal genome is much faster than that of the maternal genome, and by the end of the zygotic stage the genome-wide methylation level in male pronuclei is already lower than that in female pronuclei. The inverse correlation between promoter methylation and gene expression gradually strengthens during early embryonic development, reaching its peak at the post-implantation stage. Furthermore, we show that active genes, with the trimethylation of histone H3 at lysine 4 (H3K4me3) mark at the promoter regions in pluripotent human embryonic stem cells, are essentially devoid of DNA methylation in both mature gametes and throughout pre-implantation development. Finally, we also show that long interspersed nuclear elements or short interspersed nuclear elements that are evolutionarily young are demethylated to a milder extent compared to older elements in the same family and have higher abundance of transcripts, indicating that early embryos tend to retain higher residual methylation at the evolutionarily younger and more active transposable elements. Our work provides insights into the critical features of the methylome of human early embryos, as well as its functional relation to the regulation of gene expression and the repression of transposable elements.


Assuntos
Metilação de DNA , Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Animais , Elementos de DNA Transponíveis/genética , Embrião de Mamíferos , Células-Tronco Embrionárias/fisiologia , Feminino , Perfilação da Expressão Gênica , Células Germinativas/metabolismo , Histonas/metabolismo , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Masculino , Camundongos , Regiões Promotoras Genéticas/genética , Elementos Nucleotídeos Curtos e Dispersos/genética
9.
J Am Chem Soc ; 140(41): 13190-13194, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30278133

RESUMO

High-resolution detection of genome-wide 5-hydroxymethylcytosine (5hmC) sites of small-scale samples remains challenging. Here, we present hmC-CATCH, a bisulfite-free, base-resolution method for the genome-wide detection of 5hmC. hmC-CATCH is based on selective 5hmC oxidation, chemical labeling and subsequent C-to-T transition during PCR. Requiring only nanoscale input genomic DNA samples, hmC-CATCH enabled us to detect genome-wide hydroxymethylome of human embryonic stem cells in a cost-effective manner. Further application of hmC-CATCH to cell-free DNA (cfDNA) of healthy donors and cancer patients revealed base-resolution hydroxymethylome in the human cfDNA for the first time. We anticipate that our chemical biology approach will find broad applications in hydroxymethylome analysis of limited biological and clinical samples.


Assuntos
5-Metilcitosina/análogos & derivados , Ácidos Nucleicos Livres/química , Genômica/métodos , 5-Metilcitosina/análise , 5-Metilcitosina/química , Ácidos Nucleicos Livres/genética , Células-Tronco Embrionárias/química , Genoma , Humanos , Técnicas de Amplificação de Ácido Nucleico , Oxirredução , Análise de Sequência de DNA
10.
Biol Reprod ; 99(2): 319-325, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29579157

RESUMO

Prion protein (PrP) is encoded by a single copy gene Prnp in many cell and tissue types. PrP is very famous for its infectious conformers (PrPSC) resulting in transmissible spongiform encephalopathies. At present, physiological functions of its cellular isoform (PrPC) remain ambiguous. Although PrPC expression has been found in uterus, whether it functions in maternal-fetal dialogue during early pregnant is unknown. In this study, we examined PrPC mRNA and protein in the uterus of peri-implantation mice, and found that they were expressed with a spatiotemporal dynamic pattern. Interestingly, PrPC was significantly increased in the decidual zones around the implanting embryos at the implantation window stage. To further demonstrate that PrPC is involved in the decidualization of mouse uterus during embryo implantation, we constructed the artificial decidualization models and the delayed implantation models. Once the pseudopregnant mice were artificially induced to decidualization, the PrPC expression then increased significantly in the decidua zone. And also, if the delayed implantation embryos were allowed to implant, PrPC protein was also simultaneously improved in stromal cells surrounding the implanting embryos. Moreover, PrPC expression can be inhibited by progesterone but upregulated by estrogen in mouse uterus. These results suggest that PrPC may play an important role in embryo implantation and decidualization.


Assuntos
Implantação do Embrião/fisiologia , Proteínas Priônicas/metabolismo , Útero/metabolismo , Animais , Decídua/efeitos dos fármacos , Decídua/metabolismo , Implantação do Embrião/efeitos dos fármacos , Implantação Tardia do Embrião/efeitos dos fármacos , Implantação Tardia do Embrião/fisiologia , Estradiol/farmacologia , Feminino , Camundongos , Progesterona/farmacologia , Pseudogravidez/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Útero/efeitos dos fármacos
11.
J Biol Chem ; 291(9): 4386-98, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26719341

RESUMO

The epigenetic regulation of spatiotemporal gene expression is crucial for human development. Here, we present whole-genome chromatin immunoprecipitation followed by high throughput DNA sequencing (ChIP-seq) analyses of a wide variety of histone markers in the brain, heart, and liver of early human embryos shortly after their formation. We identified 40,181 active enhancers, with a large portion showing tissue-specific and developmental stage-specific patterns, pointing to their roles in controlling the ordered spatiotemporal expression of the developmental genes in early human embryos. Moreover, using sequential ChIP-seq, we showed that all three organs have hundreds to thousands of bivalent domains that are marked by both H3K4me3 and H3K27me3, probably to keep the progenitor cells in these organs ready for immediate differentiation into diverse cell types during subsequent developmental processes. Our work illustrates the potentially critical roles of tissue-specific and developmental stage-specific epigenomes in regulating the spatiotemporal expression of developmental genes during early human embryonic development.


Assuntos
Encéfalo/embriologia , Cromatina/metabolismo , Epigênese Genética , Coração/embriologia , Histonas/metabolismo , Fígado/embriologia , Processamento de Proteína Pós-Traducional , Feto Abortado/metabolismo , Biomarcadores/metabolismo , Encéfalo/metabolismo , China , Cromatina/química , Bases de Dados de Ácidos Nucleicos , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Biblioteca Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Histonas/genética , Humanos , Fígado/metabolismo , Lisina/metabolismo , Metilação , Miocárdio/metabolismo , Especificidade de Órgãos , Análise de Sequência de DNA , Especificidade da Espécie
12.
Genome Res ; 23(12): 2126-35, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24179143

RESUMO

DNA methylation is crucial for a wide variety of biological processes, yet no technique suitable for the methylome analysis of DNA methylation at single-cell resolution is available. Here, we describe a methylome analysis technique that enables single-cell and single-base resolution DNA methylation analysis based on reduced representation bisulfite sequencing (scRRBS). The technique is highly sensitive and can detect the methylation status of up to 1.5 million CpG sites within the genome of an individual mouse embryonic stem cell (mESC). Moreover, we show that the technique can detect the methylation status of individual CpG sites in a haploid sperm cell in a digitized manner as either unmethylated or fully methylated. Furthermore, we show that the demethylation dynamics of maternal and paternal genomes after fertilization can be traced within the individual pronuclei of mouse zygotes. The demethylation process of the genic regions is faster than that of the intergenic regions in both male and female pronuclei. Our method paves the way for the exploration of the dynamic methylome landscapes of individual cells at single-base resolution during physiological processes such as embryonic development, or during pathological processes such as tumorigenesis.


Assuntos
Núcleo Celular/genética , Metilação de DNA , Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias/metabolismo , Análise de Sequência de DNA/métodos , Animais , Células Cultivadas , Ilhas de CpG , Desenvolvimento Embrionário/genética , Epigênese Genética , Feminino , Fertilização , Genoma , Haploidia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Anotação de Sequência Molecular , Reprodutibilidade dos Testes , Análise de Célula Única , Espermatozoides/metabolismo , Zigoto/metabolismo
13.
Genome Med ; 15(1): 115, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38111063

RESUMO

Identifying expressed somatic mutations from single-cell RNA sequencing data de novo is challenging but highly valuable. We propose RESA - Recurrently Expressed SNV Analysis, a computational framework to identify expressed somatic mutations from scRNA-seq data. RESA achieves an average precision of 0.77 on three in silico spike-in datasets. In extensive benchmarking against existing methods using 19 datasets, RESA consistently outperforms them. Furthermore, we applied RESA to analyze intratumor mutational heterogeneity in a melanoma drug resistance dataset. By enabling high precision detection of expressed somatic mutations, RESA substantially enhances the reliability of mutational analysis in scRNA-seq. RESA is available at https://github.com/ShenLab-Genomics/RESA .


Assuntos
Melanoma , Análise de Célula Única , Humanos , Reprodutibilidade dos Testes , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Mutação , Melanoma/genética , Perfilação da Expressão Gênica/métodos , Análise por Conglomerados , Software
14.
NPJ Precis Oncol ; 7(1): 25, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864091

RESUMO

Immune checkpoint blockade (ICB) has demonstrated efficacy in patients with melanoma, but many exhibit poor responses. Using single cell RNA sequencing of melanoma patient-derived circulating tumor cells (CTCs) and functional characterization using mouse melanoma models, we show that the KEAP1/NRF2 pathway modulates sensitivity to ICB, independently of tumorigenesis. The NRF2 negative regulator, KEAP1, shows intrinsic variation in expression, leading to tumor heterogeneity and subclonal resistance.

15.
Cell Rep ; 42(3): 112129, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36821441

RESUMO

TGF-ß induces senescence in embryonic tissues. Whether TGF-ß in the hypoxic tumor microenvironment (TME) induces senescence in cancer and how the ensuing senescence-associated secretory phenotype (SASP) remodels the cellular TME to influence immune checkpoint inhibitor (ICI) responses are unknown. We show that TGF-ß induces a deeper senescent state under hypoxia than under normoxia; deep senescence correlates with the degree of E2F suppression and is marked by multinucleation, reduced reentry into proliferation, and a distinct 14-gene SASP. Suppressing TGF-ß signaling in tumors in an immunocompetent mouse lung cancer model abrogates endogenous senescent cells and suppresses the 14-gene SASP and immune infiltration. Untreated human lung cancers with a high 14-gene SASP display immunosuppressive immune infiltration. In a lung cancer clinical trial of ICIs, elevated 14-gene SASP is associated with increased senescence, TGF-ß and hypoxia signaling, and poor progression-free survival. Thus, TME-induced senescence may represent a naturally occurring state in cancer, contributing to an immune-suppressive phenotype associated with immune therapy resistance.


Assuntos
Neoplasias Pulmonares , Fator de Crescimento Transformador beta , Camundongos , Animais , Humanos , Fenótipo , Modelos Animais de Doenças , Microambiente Celular , Microambiente Tumoral , Senescência Celular/fisiologia
16.
Chemosphere ; 295: 133929, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35149017

RESUMO

It still remains a hotspot and great challenge to efficiently remove the nitrate nitrogen from high salt wastewater. Herein, a novel three dimensional porous bimetallic copper-nickel alloy electrode was fabricated with Ni foam (NiF) as substrate. The physicochemical and electrochemical characterization results showed Cu-Ni/NiF electrode possessed the smaller particle size (0.3-1.0 µm) and electrode film resistance comparing with Ni/NiF and Cu/NiF electrodes. Besides, higher double layer capacitance (Cdl) for Cu-Ni/NiF electrode indicated more electrochemical active sites could be used in the electrochemical nitrate nitrogen (NO3--N) removal. The electrochemical experiments showed the Cu-Ni/NiF electrode had the optimal NO3--N reduction ability and almost 100% NO3--N removal could be achieved with 30 min. All NO3--N removal processes were in accord with the pseudo-first-order reaction kinetics completely. The gaseous nitrogen selectivity for Cu-Ni/NiF electrode could reach 80.9% within 300 min. Stability assessment experiments indicated the Cu-Ni/NiF electrode all kept an excellent stability with Na2SO4 or NaCl electrolyte and the Cl- addition could significantly improve the gaseous nitrogen selectivity. Finally, a possible removal mechanism of NO3--N was proposed. This work offered a direction for designing non-noble bimetallic electrodes for nitrate removal.


Assuntos
Nitratos , Nitrogênio , Eletrodos , Nitratos/química , Óxidos de Nitrogênio
17.
ACS Appl Mater Interfaces ; 14(17): 19388-19396, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35442619

RESUMO

Ethylene (C2H4) is an important product in carbon dioxide electroreduction (CO2RR) because of the essential role it plays in chemical industry. While several strategies have been proposed to tune the selectivity of Cu-based catalysts in order to achieve high C2H4 faradaic efficiency, maintaining high selectivity toward C2H4 in CO2RR remains an unresolved problem hampering the deployment of CO2 conversion technology due to the lack of stable electrocatalysts. Here, we develop a facile method to deposit a layer of Cu2O on Cu foil by an electrochemical pulsed potential treatment. This method is capable to easily scale up and synthesize multiple electrodes in one step. After the synthesis, the pulsed copper foil, denoted as P-Cu, exhibits good C2H4 faradaic efficiency of ∼50% in CO2RR at a potential around -1.0 V vs. RHE. The C2H4 selectivity is also found to be quantitatively correlated with the roughness factor (RF) of Cu-based catalysts. More importantly, for the first time, we demonstrate that the P-Cu electrode is quite durable in CO2RR to produce C2H4 for more than 6 months.

18.
J Virol ; 84(21): 11487-95, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20702614

RESUMO

Bluetongue (BT), caused by Bluetongue virus (BTV), is an economically important disease affecting sheep, deer, cattle, and goats. Since 1998, a series of BT outbreaks have spread across much of southern and central Europe. To study why the epidemiology of the virus happens to change, it is important to fully know the mechanisms resulting in its genetic diversity. Gene mutation and segment reassortment have been considered as the key forces driving the evolution of BTV. However, it is still unknown whether intragenic recombination can occur and contribute to the process in the virus. We present here several BTV groups containing mosaic genes to reveal that intragenic recombination can take place between the virus strains and play a potential role in bringing novel BTV lineages.


Assuntos
Vírus Bluetongue/genética , Bluetongue/virologia , Variação Genética , Animais , Bluetongue/epidemiologia , Recombinação Genética , Ruminantes
19.
Cancer Discov ; 11(3): 678-695, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33203734

RESUMO

Circulating tumor cells (CTC) are shed by cancer into the bloodstream, where a viable subset overcomes oxidative stress to initiate metastasis. We show that single CTCs from patients with melanoma coordinately upregulate lipogenesis and iron homeostasis pathways. These are correlated with both intrinsic and acquired resistance to BRAF inhibitors across clonal cultures of BRAF-mutant CTCs. The lipogenesis regulator SREBP2 directly induces transcription of the iron carrier Transferrin (TF), reducing intracellular iron pools, reactive oxygen species, and lipid peroxidation, thereby conferring resistance to inducers of ferroptosis. Knockdown of endogenous TF impairs tumor formation by melanoma CTCs, and their tumorigenic defects are partially rescued by the lipophilic antioxidants ferrostatin-1 and vitamin E. In a prospective melanoma cohort, presence of CTCs with high lipogenic and iron metabolic RNA signatures is correlated with adverse clinical outcome, irrespective of treatment regimen. Thus, SREBP2-driven iron homeostatic pathways contribute to cancer progression, drug resistance, and metastasis. SIGNIFICANCE: Through single-cell analysis of primary and cultured melanoma CTCs, we have uncovered intrinsic cancer cell heterogeneity within lipogenic and iron homeostatic pathways that modulates resistance to BRAF inhibitors and to ferroptosis inducers. Activation of these pathways within CTCs is correlated with adverse clinical outcome, pointing to therapeutic opportunities.This article is highlighted in the In This Issue feature, p. 521.


Assuntos
Ferroptose/genética , Lipogênese/genética , Melanoma/genética , Melanoma/metabolismo , Células Neoplásicas Circulantes/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Transferrina/metabolismo , Biomarcadores Tumorais , Células Cultivadas , Suscetibilidade a Doenças , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Melanoma/patologia , Mutação , Células Neoplásicas Circulantes/patologia , Transdução de Sinais , Análise de Célula Única , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
20.
Data Brief ; 30: 105192, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32300612

RESUMO

To better understand the extent of how the air temperature and mean radiant temperature may vary both spatially and temporally in a radiantly heated space, we conducted a seven-day experiment in the architectural laboratory at School of Architecture, Princeton University. The primary intent of this paper was to decouple the measurement of the air temperature and mean radiant temperature. We collected a large dataset that shows temporal and spatial variations. To do so, we used non-contact infrared thermometer to measure the surface temperatures of the surrounding surfaces inside the laboratory. The geometry of the laboratory is simplified into a box, the corresponding view factor from every point within the box can be calculated towards each internal surface. These view factors are then combined with the measured surface temperatures to produce mean radiant temperatures. This spatial mean radiant temperature distribution was then compared with the air temperature distribution measured by the air temperature sensors suspended from the ceiling of the laboratory. We believe making these data available will help future researchers working on similar problems to develop protocols than the state-of-the-art measurement techniques observed among different thermal comfort or radiant heat transfer research.

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