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1.
Genes Dev ; 35(5-6): 335-353, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33602870

RESUMO

mSWI/SNF or BAF chromatin regulatory complexes are dosage-sensitive regulators of human neural development frequently mutated in autism spectrum disorders and intellectual disability. Cell cycle exit and differentiation of neural stem/progenitor cells is accompanied by BAF subunit switching to generate neuron-specific nBAF complexes. We manipulated the timing of BAF subunit exchange in vivo and found that early loss of the npBAF subunit BAF53a stalls the cell cycle to disrupt neurogenesis. Loss of BAF53a results in decreased chromatin accessibility at specific neural transcription factor binding sites, including the pioneer factors SOX2 and ASCL1, due to Polycomb accumulation. This results in repression of cell cycle genes, thereby blocking cell cycle progression and differentiation. Cell cycle block upon Baf53a deletion could be rescued by premature expression of the nBAF subunit BAF53b but not by other major drivers of proliferation or differentiation. WNT, EGF, bFGF, SOX2, c-MYC, or PAX6 all fail to maintain proliferation in the absence of BAF53a, highlighting a novel mechanism underlying neural progenitor cell cycle exit in the continued presence of extrinsic proliferative cues.


Assuntos
Actinas/metabolismo , Ciclo Celular/genética , Córtex Cerebelar/embriologia , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Actinas/genética , Animais , Sítios de Ligação/genética , Células Cultivadas , Cromatina/genética , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA/genética , Embrião de Mamíferos , Deleção de Genes , Genes cdc/genética , Camundongos , Neurogênese/genética , Proteínas do Grupo Polycomb/metabolismo , Fatores de Transcrição/metabolismo
2.
Cell ; 148(4): 651-63, 2012 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-22341440

RESUMO

To assess telomerase as a cancer therapeutic target and determine adaptive mechanisms to telomerase inhibition, we modeled telomerase reactivation and subsequent extinction in T cell lymphomas arising in Atm(-/-) mice engineered with an inducible telomerase reverse transcriptase allele. Telomerase reactivation in the setting of telomere dysfunction enabled full malignant progression with alleviation of telomere dysfunction-induced checkpoints. These cancers possessed copy number alterations targeting key loci in human T cell lymphomagenesis. Upon telomerase extinction, tumor growth eventually slowed with reinstatement of telomere dysfunction-induced checkpoints, yet growth subsequently resumed as tumors acquired alternative lengthening of telomeres (ALT) and aberrant transcriptional networks centering on mitochondrial biology and oxidative defense. ALT+ tumors acquired amplification/overexpression of PGC-1ß, a master regulator of mitochondrial biogenesis and function, and they showed marked sensitivity to PGC-1ß or SOD2 knockdown. Genetic modeling of telomerase extinction reveals vulnerabilities that motivate coincidental inhibition of mitochondrial maintenance and oxidative defense mechanisms to enhance antitelomerase cancer therapy.


Assuntos
Mitocôndrias , Telomerase/antagonistas & inibidores , Homeostase do Telômero , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Técnicas de Silenciamento de Genes , Genes cdc , Humanos , Linfoma de Células T/genética , Linfoma de Células T/metabolismo , Linfoma de Células T/patologia , Camundongos , Mitocôndrias/metabolismo , Invasividade Neoplásica/patologia , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinases/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores de Estrogênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Telomerase/genética , Telomerase/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/genética
3.
PLoS Genet ; 20(2): e1011159, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38377146

RESUMO

Common genetic variants in the repressive GATA-family transcription factor (TF) TRPS1 locus are associated with breast cancer risk, and luminal breast cancer cell lines are particularly sensitive to TRPS1 knockout. We introduced an inducible degron tag into the native TRPS1 locus within a luminal breast cancer cell line to identify the direct targets of TRPS1 and determine how TRPS1 mechanistically regulates gene expression. We acutely deplete over 80 percent of TRPS1 from chromatin within 30 minutes of inducing degradation. We find that TRPS1 regulates transcription of hundreds of genes, including those related to estrogen signaling. TRPS1 directly regulates chromatin structure, which causes estrogen receptor alpha (ER) to redistribute in the genome. ER redistribution leads to both repression and activation of dozens of ER target genes. Downstream from these primary effects, TRPS1 depletion represses cell cycle-related gene sets and reduces cell doubling rate. Finally, we show that high TRPS1 activity, calculated using a gene expression signature defined by primary TRPS1-regulated genes, is associated with worse breast cancer patient prognosis. Taken together, these data suggest a model in which TRPS1 modulates the genomic distribution of ER, both activating and repressing transcription of genes related to cancer cell fitness.


Assuntos
Neoplasias da Mama , Cromatina , Dedos , Doenças do Cabelo , Síndrome de Langer-Giedion , Nariz , Feminino , Humanos , Neoplasias da Mama/genética , Cromatina/genética , Receptor alfa de Estrogênio/genética , Dedos/anormalidades , Fatores de Transcrição GATA , Expressão Gênica , Genes cdc , Nariz/anormalidades , Proteínas Repressoras/genética
4.
Genes Dev ; 33(21-22): 1539-1554, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31624083

RESUMO

A universal feature of DNA damage and replication stress in eukaryotes is the activation of a checkpoint-kinase response. In S-phase, the checkpoint inhibits replication initiation, yet the function of this global block to origin firing remains unknown. To establish the physiological roles of this arm of the checkpoint, we analyzed separation of function mutants in the budding yeast Saccharomyces cerevisiae that allow global origin firing upon replication stress, despite an otherwise normal checkpoint response. Using genetic screens, we show that lack of the checkpoint-block to origin firing results in a dependence on pathways required for the resolution of topological problems. Failure to inhibit replication initiation indeed causes increased DNA catenation, resulting in DNA damage and chromosome loss. We further show that such topological stress is not only a consequence of a failed checkpoint response but also occurs in an unperturbed S-phase when too many origins fire simultaneously. Together we reveal that the role of limiting the number of replication initiation events is to prevent DNA topological problems, which may be relevant for the treatment of cancer with both topoisomerase and checkpoint inhibitors.


Assuntos
Genes cdc/genética , Origem de Replicação/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Dano ao DNA/genética , DNA Fúngico/química , DNA Fúngico/genética , Regulação Fúngica da Expressão Gênica , Mutação , Fase S , Saccharomyces cerevisiae/crescimento & desenvolvimento , Estresse Fisiológico/genética
5.
Nucleic Acids Res ; 52(12): 6830-6849, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38747345

RESUMO

A-MYB (MYBL1) is a transcription factor with a role in meiosis in spermatocytes. The related B-MYB protein is a key oncogene and a master regulator activating late cell cycle genes. To activate genes, B-MYB forms a complex with MuvB and is recruited indirectly to cell cycle genes homology region (CHR) promoter sites of target genes. Activation through the B-MYB-MuvB (MMB) complex is essential for successful mitosis. Here, we discover that A-MYB has a function in transcriptional regulation of the mitotic cell cycle and can substitute for B-MYB. Knockdown experiments in cells not related to spermatogenesis show that B-MYB loss alone merely delays cell cycle progression. Only dual knockdown of B-MYB and A-MYB causes G2/M cell cycle arrest, endoreduplication, and apoptosis. A-MYB can substitute for B-MYB in binding to MuvB. The resulting A-MYB-MuvB complex activates genes through CHR sites. We find that A-MYB activates the same target genes as B-MYB. Many of the corresponding proteins are central regulators of the cell division cycle. In summary, we demonstrate that A-MYB is an activator of the mitotic cell cycle by activating late cell cycle genes.


Assuntos
Proteínas de Ciclo Celular , Proliferação de Células , Transativadores , Animais , Proliferação de Células/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Transativadores/metabolismo , Transativadores/genética , Camundongos , Humanos , Apoptose/genética , Regiões Promotoras Genéticas , Mitose/genética , Masculino , Ciclo Celular/genética , Genes cdc , Ativação Transcricional , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Linhagem Celular , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Regulação da Expressão Gênica
6.
Proc Natl Acad Sci U S A ; 120(10): e2219439120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36853944

RESUMO

Multiple myeloma (MM), a tumor of germinal center (GC)-experienced plasma cells, comprises distinct genetic subgroups, such as the t(11;14)/CCND1 and the t(4;14)/MMSET subtype. We have generated genetically defined, subgroup-specific MM models by the GC B cell-specific coactivation of mouse Ccnd1 or MMSET with a constitutively active Ikk2 mutant, mimicking the secondary NF-κB activation frequently seen in human MM. Ccnd1/Ikk2ca and MMSET/Ikk2ca mice developed a pronounced, clonally restricted plasma cell outgrowth with age, accompanied by serum M spikes, bone marrow insufficiency, and bone lesions. The transgenic plasma cells could be propagated in vivo and showed distinct transcriptional profiles, resembling their human MM counterparts. Thus, we show that targeting the expression of genes involved in MM subgroup-specific chromosomal translocations into mouse GC B cells translates into distinct MM-like diseases that recapitulate key features of the human tumors, opening the way to a better understanding of the pathogenesis and therapeutic vulnerabilities of different MM subgroups.


Assuntos
Mieloma Múltiplo , Humanos , Animais , Camundongos , Mieloma Múltiplo/genética , Plasmócitos , Linfócitos B , Genes cdc , Animais Geneticamente Modificados , Modelos Animais de Doenças
7.
Genes Dev ; 32(1): 58-69, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29437725

RESUMO

Histone acetylation is associated with active transcription in eukaryotic cells. It helps to open up the chromatin by neutralizing the positive charge of histone lysine residues and providing binding platforms for "reader" proteins. The bromodomain (BRD) has long been thought to be the sole protein module that recognizes acetylated histones. Recently, we identified the YEATS domain of AF9 (ALL1 fused gene from chromosome 9) as a novel acetyl-lysine-binding module and showed that the ENL (eleven-nineteen leukemia) YEATS domain is an essential acetyl-histone reader in acute myeloid leukemias. The human genome encodes four YEATS domain proteins, including GAS41, a component of chromatin remodelers responsible for H2A.Z deposition onto chromatin; however, the importance of the GAS41 YEATS domain in human cancer remains largely unknown. Here we report that GAS41 is frequently amplified in human non-small cell lung cancer (NSCLC) and is required for cancer cell proliferation, survival, and transformation. Biochemical and crystal structural studies demonstrate that GAS41 binds to histone H3 acetylated on H3K27 and H3K14, a specificity that is distinct from that of AF9 or ENL. ChIP-seq (chromatin immunoprecipitation [ChIP] followed by high-throughput sequencing) analyses in lung cancer cells reveal that GAS41 colocalizes with H3K27ac and H3K14ac on the promoters of actively transcribed genes. Depletion of GAS41 or disruption of the interaction between its YEATS domain and acetylated histones impairs the association of histone variant H2A.Z with chromatin and consequently suppresses cancer cell growth and survival both in vitro and in vivo. Overall, our study identifies GAS41 as a histone acetylation reader that promotes histone H2A.Z deposition in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Amplificação de Genes , Genes cdc , Histonas/fisiologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Regiões Promotoras Genéticas , Domínios e Motivos de Interação entre Proteínas , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
8.
Blood ; 141(10): 1209-1220, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36375119

RESUMO

Understanding the functional role of mutated genes in cancer is required to translate the findings of cancer genomics into therapeutic improvement. BTG1 is recurrently mutated in the MCD/C5 subtype of diffuse large B-cell lymphoma (DLBCL), which is associated with extranodal dissemination. Here, we provide evidence that Btg1 knock out accelerates the development of a lethal lymphoproliferative disease driven by Bcl2 overexpression. Furthermore, we show that the scaffolding protein BCAR1 is a BTG1 partner. Moreover, after BTG1 deletion or expression of BTG1 mutations observed in patients with DLBCL, the overactivation of the BCAR1-RAC1 pathway confers increased migration ability in vitro and in vivo. These modifications are targetable with the SRC inhibitor dasatinib, which opens novel therapeutic opportunities in BTG1 mutated DLBCL.


Assuntos
Linfoma Difuso de Grandes Células B , Humanos , Linfoma Difuso de Grandes Células B/patologia , Mutação , Genes cdc , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteína Substrato Associada a Crk/genética , Proteína Substrato Associada a Crk/metabolismo
9.
Immunity ; 44(2): 343-54, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26872698

RESUMO

Checkpoint blockade immunotherapies can be extraordinarily effective, but might benefit only the minority of patients whose tumors are pre-infiltrated by T cells. Here, using lung adenocarcinoma mouse models, including genetic models, we show that autochthonous tumors that lacked T cell infiltration and resisted current treatment options could be successfully sensitized to host antitumor T cell immunity when appropriately selected immunogenic drugs (e.g., oxaliplatin combined with cyclophosphamide for treatment against tumors expressing oncogenic Kras and lacking Trp53) were used. The antitumor response was triggered by direct drug actions on tumor cells, relied on innate immune sensing through toll-like receptor 4 signaling, and ultimately depended on CD8(+) T cell antitumor immunity. Furthermore, instigating tumor infiltration by T cells sensitized tumors to checkpoint inhibition and controlled cancer durably. These findings indicate that the proportion of cancers responding to checkpoint therapy can be feasibly and substantially expanded by combining checkpoint blockade with immunogenic drugs.


Assuntos
Adenocarcinoma/terapia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Imunoterapia/métodos , Neoplasias Pulmonares/terapia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Adenocarcinoma/imunologia , Animais , Linhagem Celular Tumoral , Sensibilização do Sistema Nervoso Central/efeitos dos fármacos , Ciclofosfamida/administração & dosagem , Modelos Animais de Doenças , Tratamento Farmacológico/métodos , Genes cdc/efeitos dos fármacos , Humanos , Imunidade Inata , Neoplasias Pulmonares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Receptor 4 Toll-Like/metabolismo
10.
Nucleic Acids Res ; 51(9): 4266-4283, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-36864753

RESUMO

YAP, the key protein effector of the Hippo pathway, is a transcriptional co-activator that controls the expression of cell cycle genes, promotes cell growth and proliferation and regulates organ size. YAP modulates gene transcription by binding to distal enhancers, but the mechanisms of gene regulation by YAP-bound enhancers remain poorly understood. Here we show that constitutive active YAP5SA leads to widespread changes in chromatin accessibility in untransformed MCF10A cells. Newly accessible regions include YAP-bound enhancers that mediate activation of cycle genes regulated by the Myb-MuvB (MMB) complex. By CRISPR-interference we identify a role for YAP-bound enhancers in phosphorylation of Pol II at Ser5 at MMB-regulated promoters, extending previously published studies that suggested YAP primarily regulates the pause-release step and transcriptional elongation. YAP5SA also leads to less accessible 'closed' chromatin regions, which are not directly YAP-bound but which contain binding motifs for the p53 family of transcription factors. Diminished accessibility at these regions is, at least in part, a consequence of reduced expression and chromatin-binding of the p53 family member ΔNp63 resulting in downregulation of ΔNp63-target genes and promoting YAP-mediated cell migration. In summary, our studies uncover changes in chromatin accessibility and activity that contribute to the oncogenic activities of YAP.


Assuntos
Proteínas de Ciclo Celular , Movimento Celular , Cromatina , Genes cdc , Fatores de Transcrição , Transcrição Gênica , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Movimento Celular/genética , Cromatina/genética , Cromatina/metabolismo , Genes cdc/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas de Sinalização YAP/química , Proteínas de Sinalização YAP/metabolismo , Humanos , Linhagem Celular , Elementos Facilitadores Genéticos , DNA Polimerase II/química , DNA Polimerase II/metabolismo , Fosforilação
11.
Proc Natl Acad Sci U S A ; 119(49): e2113504119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36454750

RESUMO

Alternative polyadenylation (APA) plays an important role in posttranscriptional gene regulation such as transcript stability and translation efficiency. However, our knowledge about APA dynamics at the single-cell level is largely unexplored. Here, we developed single-cell polyadenylation sequencing, a strand-specific approach for sequencing the 3' end of transcripts, to investigate the landscape of APA at the single-cell level. By analyzing several cell lines, we found many genes using multiple polyA sites in bulk data are prone to use only one polyA site in each single cell. Interestingly, cell cycle genes were significantly enriched in genes with high variation in polyA site usages. Furthermore, the 414 genes showing a polyA site usage switch after cell synchronization enriched cell cycle genes, while the differentially expressed genes after cell synchronization did not enrich cell cycle genes. We further identified 812 genes showing polyA site usage changes between neighboring cell cycles, which were grouped into six clusters, with cell phase-specific functional categories enriched in each cluster. Deletion of one polyA site in MSL1 and SCCPDH results in slower and faster cell cycle progression, respectively, supporting polyA site usage switch played an important role in cell cycle. These results indicate that APA is an important layer for cell cycle regulation.


Assuntos
Poli A , Poliadenilação , Poliadenilação/genética , Genes cdc , Ciclo Celular/genética , Divisão Celular
12.
PLoS Genet ; 18(11): e1010528, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36449519

RESUMO

The relationship between cohesin-mediated chromatin looping and gene expression remains unclear. NIPBL and WAPL are two opposing regulators of cohesin activity; depletion of either is associated with changes in both chromatin folding and transcription across a wide range of cell types. However, a direct comparison of their individual and combined effects on gene expression in the same cell type is lacking. We find that NIPBL or WAPL depletion in human HCT116 cells each alter the expression of ~2,000 genes, with only ~30% of the genes shared between the conditions. We find that clusters of differentially expressed genes within the same topologically associated domain (TAD) show coordinated misexpression, suggesting some genomic domains are especially sensitive to both more or less cohesin. Finally, co-depletion of NIPBL and WAPL restores the majority of gene misexpression as compared to either knockdown alone. A similar set of NIPBL-sensitive genes are rescued following CTCF co-depletion. Together, this indicates that altered transcription due to reduced cohesin activity can be functionally offset by removal of either its negative regulator (WAPL) or the physical barriers (CTCF) that restrict loop-extrusion events.


Assuntos
Proteínas de Ciclo Celular , Cromatina , Proteínas Cromossômicas não Histona , Regulação da Expressão Gênica , Humanos , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina/genética , Genes cdc , Genoma , Células HCT116 , Coesinas
13.
PLoS Genet ; 18(8): e1010349, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36037231

RESUMO

A network of transcription factors (TFs) coordinates transcription with cell cycle events in eukaryotes. Most TFs in the network are phosphorylated by cyclin-dependent kinase (CDK), which limits their activities during the cell cycle. Here, we investigate the physiological consequences of disrupting CDK regulation of the paralogous repressors Yhp1 and Yox1 in yeast. Blocking Yhp1/Yox1 phosphorylation increases their levels and decreases expression of essential cell cycle regulatory genes which, unexpectedly, increases cellular fitness in optimal growth conditions. Using synthetic genetic interaction screens, we find that Yhp1/Yox1 mutations improve the fitness of mutants with mitotic defects, including condensin mutants. Blocking Yhp1/Yox1 phosphorylation simultaneously accelerates the G1/S transition and delays mitotic exit, without decreasing proliferation rate. This mitotic delay partially reverses the chromosome segregation defect of condensin mutants, potentially explaining their increased fitness when combined with Yhp1/Yox1 phosphomutants. These findings reveal how altering expression of cell cycle genes leads to a redistribution of cell cycle timing and confers a fitness advantage to cells.


Assuntos
Genes cdc , Proteínas de Saccharomyces cerevisiae , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Mitose/genética , Fosforilação , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
BMC Cancer ; 24(1): 129, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267901

RESUMO

BACKGROUND: Esophageal cancer (EC) is a deadly disease with limited therapeutic options. Although circulating tumor DNA (ctDNA) could be a promising tool in this regard, the availiable evidence is limited. We performed a systematic review and meta-analysis to summarize the clinical applicability of the next-generation sequencing (NGS) and droplet digital polymerase chain reaction (ddPCR) technology on the ctDNA detection of the EC and listed the current challenges. METHODS: We systematically searched MEDLINE (via PubMed), Embase (via OVID), ISI Web of Science database and Cochrane Library from January, 2000 to April, 2023. Progression-free survival (PFS) and overall survival (OS) were set as primary outcome endpoints. Pathologic response was evaluated by tumor regression grade (TRG), according to the eighth edition of the American Joint Committee on Cancer (AJCC). Major pathologic regression (MPR) was defined as TRG 1 and 2. The MPR was set as secondary endpoint. Hazard rate (HR) and associated 95% CI were used as the effect indicators the association between ctDNA and prognosis of EC. MPR rates were also calculated. Fixed-effect model (Inverse Variance) or random-effect model (Mantel-Haenszel method) was performed depending on the statistically heterogeneity. RESULTS: Twenty-two studies, containing 1144 patients with EC, were included in this meta-analysis. The results showed that OS (HR = 3.87; 95% CI, 2.86-5.23) and PFS (HR = 4.28; 95% CI, 3.34-5.48) were shorter in ctDNA-positive patients. In the neoadjuvant therapy, the sensitivity analysis showed the clarified HR of ctDNA-positive was 1.13(95% CI, 1.01-1.28). We also found that TP53, NOTCH1, CCND1 and CNKN2A are the most frequent mutation genes. CONCLUSIONS: Positive ctDNA is associated with poor prognosis, which demonstrated clinical value of ctDNA. Longitudinal ctDNA monitoring showed potential prognostic value in the neoadjuvant therapy. In an era of precision medicine, ctDNA could be a promising tool to individualize treatment planning and to improve outcomes in EC. PROSPERO REGISTRATION NUMBER: CRD42023412465.


Assuntos
DNA Tumoral Circulante , Neoplasias Esofágicas , Humanos , DNA Tumoral Circulante/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/terapia , Bases de Dados Factuais , Biblioteca Gênica , Genes cdc
15.
Mol Biol Rep ; 51(1): 166, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252343

RESUMO

BACKGROUND: Genomic imprinting refers to expressing parent-specific genes in mammalian diploid cells. The NDN gene is maternally imprinted in humans and mice and correlates with the timing of puberty. This study aimed to investigate its imprinting status and its relationship with the onset of puberty in Dolang sheep. METHODS AND RESULTS: In this study, cloning and sequencing obtained the NDN gene cDNA sequence of 1082 bp of Dolang sheep, coding for 325 amino acids. Similarity analysis and phylogenetic tree showed that the NDN gene conformed to the law of speciation and was highly conserved among mammals. RT-qPCR results showed the highest expression of NDN mRNA was found in the hypothalamus at puberty, and the expression was significantly increased and then significantly decreased from prepuberty to postpuberty in the hypothalamus, pituitary, and ovary and oviduct. Based on expressed single nucleotide polymorphism (SNP), the NDN gene was expressed monoallelically in the tissues of adult and neonatal umbilical cords, and the expressed allele was paternally inherited. The NDN promoter region of 3400 bp was obtained by cloning and identified in monoallelic-expressing tissues (hypothalamus, ovary, spleen) as a differentially methylated region (DMR). CONCLUSION: These findings will enrich the number of imprinted genes in sheep and suggest that the NDN gene could be a candidate gene for studying puberty initiation in Dolang sheep.


Assuntos
Aminoácidos , Genes cdc , Animais , Feminino , Alelos , Clonagem Molecular , Filogenia , Ovinos/genética
16.
PLoS Genet ; 17(11): e1009935, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34843473

RESUMO

Genome copy number variation occurs during each mitotic and meiotic cycle and it is crucial for organisms to maintain their natural ploidy. Defects in ploidy transitions can lead to chromosome instability, which is a hallmark of cancer. Ploidy in the haploid human fungal pathogen Cryptococcus neoformans is exquisitely orchestrated and ranges from haploid to polyploid during sexual development and under various environmental and host conditions. However, the mechanisms controlling these ploidy transitions are largely unknown. During C. deneoformans (formerly C. neoformans var. neoformans, serotype D) unisexual reproduction, ploidy increases prior to the onset of meiosis, can be independent from cell-cell fusion and nuclear fusion, and likely occurs through an endoreplication pathway. To elucidate the molecular mechanisms underlying this ploidy transition, we identified twenty cell cycle-regulating genes encoding cyclins, cyclin-dependent kinases (CDK), and CDK regulators. We characterized four cyclin genes and two CDK regulator genes that were differentially expressed during unisexual reproduction and contributed to diploidization. To detect ploidy transition events, we generated a ploidy reporter, called NURAT, which can detect copy number increases via double selection for nourseothricin-resistant, uracil-prototrophic cells. Utilizing this ploidy reporter, we showed that ploidy transition from haploid to diploid can be detected during the early phases of unisexual reproduction. Interestingly, selection for the NURAT reporter revealed several instances of segmental aneuploidy of multiple chromosomes, which conferred azole resistance in some isolates. These findings provide further evidence of ploidy plasticity in fungi with significant biological and public health implications.


Assuntos
Cryptococcus neoformans/genética , Cryptococcus neoformans/fisiologia , Genes Fúngicos , Genes Reporter , Genes cdc , Meiose , Mitose , Ploidias , Reprodução
17.
PLoS Genet ; 17(1): e1009322, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33493195

RESUMO

DNA polymerase delta (Pol δ) plays several essential roles in eukaryotic DNA replication and repair. At the replication fork, Pol δ is responsible for the synthesis and processing of the lagging-strand. At replication origins, Pol δ has been proposed to initiate leading-strand synthesis by extending the first Okazaki fragment. Destabilizing mutations in human Pol δ subunits cause replication stress and syndromic immunodeficiency. Analogously, reduced levels of Pol δ in Saccharomyces cerevisiae lead to pervasive genome instability. Here, we analyze how the depletion of Pol δ impacts replication origin firing and lagging-strand synthesis during replication elongation in vivo in S. cerevisiae. By analyzing nascent lagging-strand products, we observe a genome-wide change in both the establishment and progression of replication. S-phase progression is slowed in Pol δ depletion, with both globally reduced origin firing and slower replication progression. We find that no polymerase other than Pol δ is capable of synthesizing a substantial amount of lagging-strand DNA, even when Pol δ is severely limiting. We also characterize the impact of impaired lagging-strand synthesis on genome integrity and find increased ssDNA and DNA damage when Pol δ is limiting; these defects lead to a strict dependence on checkpoint signaling and resection-mediated repair pathways for cellular viability.


Assuntos
DNA Polimerase III/genética , Replicação do DNA/genética , Antígeno Nuclear de Célula em Proliferação/genética , Reparo de DNA por Recombinação/genética , Dano ao DNA/genética , Reparo do DNA/genética , Genes cdc/genética , Humanos , Origem de Replicação/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
18.
Environ Toxicol ; 39(2): 695-707, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37647361

RESUMO

Angiogenesis contributes to tumor progression, aggressive behavior, and metastasis. Although several endothelial dysfunction genes (angiogenesis-related genes [ARGs]) have been identified as diagnostic biomarkers of breast cancer in a few studies, the mixed effects of ARGs have not been thoroughly investigated. The RNA sequencing data and patient survival datasets of breast cancer were obtained for further analysis. MSigDB website includes angiogenesis-related mechanisms. The consensus clustering analysis identifies 1082 breast cancer patients as three clusters. differential expression genes (DEGs) were identified by limma package. GO combined with gene set enrichment analysis (GSEA) to identify cytogenetic functions between two predefined clusters. Then Serpin Family F Member 1 (SERPINF1), angiomotin (AMOT), promyelocytic leukemia (PML), and BTG anti-proliferation factor 1 (BTG) were selected to construct prediction models using random forest survival analysis. External validation was performed using the GSE58812 triple-negative breast cancer cohort as the validation set. The median scoring system was used to discern the high- and low-risk groups, and there was a significant difference in their diagnostic results. Immunological infiltration scores were calculated using single sample gene set enrichment analysis (ssGSEA) and xCell algorithms, and consciousness scores were calculated using the R package "oncoPredict" for drugs in the Genomics of Drug Sensitivity in Cancer (GDSC) database. In addition, the single-cell analysis of seven triple-negative breast cancers using scRNA-seq information from GSE118389 demonstrated the interpretation of SERPINF1, AMOT, PML, and BTG1. In conclusion, this investigation engineered ARG-centric disease paradigms that not only prognosticated prospective therapeutic compounds, but also projected their mechanistic trajectories, thereby facilitating the proposition of tailored treatments within diverse patient cohorts diagnosed with breast cancer.


Assuntos
Medicina de Precisão , Neoplasias de Mama Triplo Negativas , Humanos , Angiogênese , Genes cdc , Neoplasias de Mama Triplo Negativas/genética
19.
Environ Toxicol ; 39(2): 657-668, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37565774

RESUMO

INTRODUCTION: Prostate cancer is a common cancer among male population. The aberrant expression of histone modifiers has been identified as a potential driving force in numerous cancer types. However, the mechanism of histone modifiers in the development of prostate cancer remains unknown. METHODS: Expression profiles and clinical data were obtained from GSE70769, GSE46602, and GSE67980. Seruat R package was utilized to calculate the gene set enrichment of the histone modification pathway and obtain the Histone score. Least absolute shrinkage and selection operator (LASSO) and Cox regression analyses were employed to identify marker genes with prognostic value. Kaplan-Meier survival analysis was conducted to assess the efficacy of the prognostic model. In addition, microenvironment cell populations counter (MCPcounter), single-sample gene set enrichment analysis (ssGSEA), and xCell algorithms were employed for immune infiltration analysis. Drug sensitivity prediction was performed using oncoPredict R package. RESULTS: We screened differentially expressed genes (DEGs) between Histone-high score (Histone-H) and Histone-low score (Histone-L) groups, which were enriched in RNA splicing and DNA-binding transcription factor binding pathways. We retained four prognostic marker genes, including TACC3, YWHAH, TAF1C and TTLL5. The risk model showed significant efficacy in stratification of the prognosis of prostate cancer patients in both internal and external cohorts (p < .0001 and p = .032, respectively). In addition, prognostic gene YWHAH was infiltrated in abundance of fibroblasts and highly correlated with Entinostat_1593 drug sensitivity score and the value of risk score. CONCLUSION: We innovatively developed a histone modification-related prognostic model with high prognostic potency and identified YWHAH as possible diagnostic and therapeutic biomarkers for prostate cancer. It provides novel insights to address prostate cancer and enhance clinical outcomes, thereby opening up a new avenue for customized treatment alternatives.


Assuntos
Histonas , Neoplasias da Próstata , Humanos , Masculino , Histonas/genética , Prognóstico , RNA-Seq , Neoplasias da Próstata/genética , Genes cdc , Microambiente Tumoral/genética , Proteínas Associadas aos Microtúbulos
20.
Int J Mol Sci ; 25(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38612390

RESUMO

Dormancy release and reactivation in temperate trees are mainly controlled by temperature and are affected by age, but the underlying molecular mechanisms are still unclear. In this study, we explored the effects of low temperatures in winter and warm temperatures in spring on dormancy release and reactivation in Larix kaempferi. Further, we established the relationships between cell-cycle genes and cambium cell division. The results showed that chilling accelerated L. kaempferi bud break overall, and the longer the duration of chilling is, the shorter the bud break time is. After dormancy release, warm temperatures induced cell-cycle gene expression; when the configuration value of the cell-cycle genes reached 4.97, the cambium cells divided and L. kaempferi reactivated. This study helps to predict the impact of climate change on wood production and provides technical support for seedling cultivation in greenhouses.


Assuntos
Larix , Larix/genética , Câmbio , Genes cdc , Divisão Celular , Mudança Climática
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