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1.
Proc Natl Acad Sci U S A ; 115(48): E11264-E11273, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30420518

RESUMO

Chronically undernourished children become stunted during their first 2 years and thereafter bear burdens of ill health for the rest of their lives. Contributors to stunting include poor nutrition and exposure to pathogens, and parental history may also play a role. However, the epigenetic impact of a poor environment on young children is largely unknown. Here we show the unfolding pattern of histone H3 lysine 4 trimethylation (H3K4me3) in children and mothers living in an urban slum in Dhaka, Bangladesh. A pattern of chromatin modification in blood cells of stunted children emerges over time and involves a global decrease in methylation at canonical locations near gene start sites and increased methylation at ectopic sites throughout the genome. This redistribution occurs at metabolic and immune genes and was specific for H3K4me3, as it was not observed for histone H3 lysine 27 acetylation in the same samples. Methylation changes in stunting globally resemble changes that occur in vitro in response to altered methylation capacity, suggesting that reduced levels of one-carbon nutrients in the diet play a key role in stunting in this population. A network of differentially expressed genes in stunted children reveals effects on chromatin modification machinery, including turnover of H3K4me3, as well as posttranscriptional gene regulation affecting immune response pathways and lipid metabolism. Consistent with these changes, reduced expression of the endocytic receptor gene LDL receptor 1 (LRP1) is a driver of stunting in a mouse model, suggesting a target for intervention.


Assuntos
Histonas/genética , Desnutrição/genética , Animais , Epigênese Genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Desnutrição/metabolismo , Metilação , Camundongos
2.
Cell Commun Signal ; 17(1): 24, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30885209

RESUMO

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) results in changes that promote de-differentiation, migration, and invasion in non-small cell lung cancer (NSCLC). While it is recognized that EMT promotes altered energy utilization, identification of metabolic pathways that link EMT with cancer progression is needed. Work presented here indicates that mesenchymal NSCLC upregulates glutamine-fructose-6-phosphate transaminase 2 (GFPT2). GFPT2 is the rate-limiting enzyme in the synthesis of uridine diphosphate N-acetylglucosamine (UDP-GlcNAc). UDP-GlcNAc is the obligate activator of O-linked N-acetylglucosamine transferase (OGT). METHODS: Analysis of our transcriptomic data indicates that GFPT2 is one of the most significantly upregulated metabolic genes in mesenchymal NSCLC. Ectopic GFPT2 expression, as well as gene silencing strategies were used to determine the importance of this metabolic enzyme in regulating EMT-driven processes of cell motility and invasion. RESULTS: Our work demonstrates that GFPT2 is transcriptionally upregulated by NF-κB and repressed by the NAD+-dependent deacetylase SIRT6. Depletion of GFPT2 expression in NSCLC highlights its importance in regulating cell migration and invasion during EMT. CONCLUSIONS: Consistent with GFPT2 promoting cancer progression, we find that elevated GFPT2 expression correlates with poor clinical outcome in NSCLC. Modulation of GFPT2 activity offers a potentially important therapeutic target to combat NSCLC disease progression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Neoplasias Pulmonares/patologia , NF-kappa B/metabolismo , Sirtuínas/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/genética , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Transdução de Sinais , Ativação Transcricional
3.
Mol Cell ; 37(4): 453-4, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20188663

RESUMO

Although IKK-related kinases are known to augment immune pathways, their importance to DNA-damage response has not been previously elucidated; in this issue of Molecular Cell, Renner et al. (2010) show that genotoxic stress requires SUMOylated IKKvarepsilon to regulate NF-kappaB transcription and cell survival.


Assuntos
Apoptose , Dano ao DNA , Quinase I-kappa B/metabolismo , Transdução de Sinais , Quinase I-kappa B/genética , Ligação Proteica , Proteína SUMO-1/metabolismo
4.
Genes Dev ; 23(7): 849-61, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19339690

RESUMO

The transcription factor NF-kappaB is a critical regulator of inflammatory and cell survival signals. Proteasomal degradation of NF-kappaB subunits plays an important role in the termination of NF-kappaB activity, and at least one of the identified ubiquitin ligases is a multimeric complex containing Copper Metabolism Murr1 Domain 1 (COMMD1) and Cul2. We report here that GCN5, a histone acetyltransferase, associates with COMMD1 and other components of the ligase, promotes RelA ubiquitination, and represses kappaB-dependent transcription. In this role, the acetyltransferase activity of GCN5 is not required. Interestingly, GCN5 binds more avidly to RelA after phosphorylation on Ser 468, an event that is dependent on IKK activity. Consistent with this, we find that both GCN5 and the IkappaB Kinase (IKK) complex promote RelA degradation. Collectively, the data indicate that GCN5 participates in the ubiquitination process as an accessory factor for a ubiquitin ligase, where it provides a novel link between phosphorylation and ubiquitination.


Assuntos
Coenzimas/metabolismo , Fator de Transcrição RelA/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Regulação da Expressão Gênica , Humanos , Quinase I-kappa B/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Estabilidade Proteica , Ubiquitinação
5.
Cancer Cell ; 12(3): 239-51, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17785205

RESUMO

LZAP has been reported to inhibit cellular proliferation and clonogenic growth. Here, we report that decreased LZAP expression promoted cellular transformation, xenograft tumor growth, and xenograft tumor vascularity. Loss of LZAP also increased cellular invasion, and MMP-9 expression dependent on NF-kappaB. LZAP directly bound to RelA, impaired serine 536 phosphorylation of RelA, increased HDAC association with RelA, inhibited basal and stimulated NF-kappaB transcriptional activity, and was found at the promoter of selective NF-kappaB-responsive genes. LZAP protein levels were markedly decreased in 32% of primary HNSCCs (n = 28) and decreased LZAP levels in primary HNSCC correlated with increased expression of the NF-kappaB-regulated genes IL-8 and IkappaBalpha. In aggregate, these data support a role of LZAP in NF-kappaB regulation and tumor suppression.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , NF-kappa B/antagonistas & inibidores , Proteínas do Tecido Nervoso/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Apoptose , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proteínas de Ciclo Celular , Transformação Celular Neoplásica/metabolismo , Regulação da Expressão Gênica , Células HeLa , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Histona Desacetilases/metabolismo , Humanos , Proteínas I-kappa B/metabolismo , Interleucina-8/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Nus , Invasividade Neoplásica , Fator de Transcrição RelA/metabolismo , Transplante Heterólogo , Fator de Necrose Tumoral alfa/fisiologia
6.
Proc Natl Acad Sci U S A ; 109(42): 16888-93, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23027940

RESUMO

The molecular mechanisms linking glucose metabolism with active transcription remain undercharacterized in mammalian cells. Using nuclear factor-κB (NF-κB) as a glucose-responsive transcription factor, we show that cells use the hexosamine biosynthesis pathway and O-linked ß-N-acetylglucosamine (O-GlcNAc) transferase (OGT) to potentiate gene expression in response to tumor necrosis factor (TNF) or etoposide. Chromatin immunoprecipitation assays demonstrate that, upon induction, OGT localizes to NF-κB-regulated promoters to enhance RelA acetylation. Knockdown of OGT abolishes p300-mediated acetylation of RelA on K310, a posttranslational mark required for full NF-κB transcription. Mapping studies reveal T305 as an important residue required for attachment of the O-GlcNAc moiety on RelA. Furthermore, p300 fails to acetylate a full-length RelA(T305A) mutant, linking O-GlcNAc and acetylation events on NF-κB. Reconstitution of RelA null cells with the RelA(T305A) mutant illustrates the importance of this residue for NF-κB-dependent gene expression and cell survival. Our work provides evidence for a unique regulation where attachment of the O-GlcNAc moiety to RelA potentiates p300 acetylation and NF-κB transcription.


Assuntos
Acetilglucosamina/metabolismo , Regulação da Expressão Gênica/fisiologia , Glucose/metabolismo , Redes e Vias Metabólicas/fisiologia , NF-kappa B/metabolismo , Fator de Transcrição RelA/metabolismo , Acetilação , Imunoprecipitação da Cromatina , DNA Complementar/genética , Ensaio de Imunoadsorção Enzimática , Etoposídeo/metabolismo , Células HEK293 , Hexosaminas/biossíntese , Humanos , Immunoblotting , Imunoprecipitação , Luciferases , Redes e Vias Metabólicas/genética , Plasmídeos/genética , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição RelA/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
J Biol Chem ; 287(1): 581-588, 2012 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-22084251

RESUMO

The serine/threonine protein kinase Akt is a critical regulator of cell growth and survival in response to growth factors. A key step in Akt activation is phosphorylation at Ser-473 by the mammalian target of rapamycin (mTOR) complex 2 (mTORC2). Although Rictor is required for the stability and activity of mTORC2, little is known about functional regions or post-translational modifications within Rictor that are responsible for regulating mTORC2. Here, we demonstrate that Rictor contains two distinct central regions critical for mTORC2 function. One we refer to as the stability region because it is critical for interaction with Sin1.1 and LST8, and a second adjacent region is required for multisite acetylation. p300-mediated acetylation of Rictor increases mTORC2 activity toward Akt, whereas site-directed mutants within the acetylation region of Rictor exhibit reduced insulin-like growth factor 1 (IGF-1)-stimulated mTORC2 kinase activity. Inhibition of deacetylases, including the NAD+-dependent sirtuins, promotes Rictor acetylation and IGF-1-mediated Akt phosphorylation. These results suggest that multiple-site acetylation of Rictor signals for increased activation of mTORC2, providing a critical link between nutrient-sensitive deacetylases and mTORC2 signaling to Akt.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Acetilação , Sítios de Ligação , Proteínas de Transporte/química , Proteínas de Transporte/genética , Células HEK293 , Células HeLa , Humanos , Mutagênese Sítio-Dirigida , Mutação , Fosforilação , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-akt/química , Proteína Companheira de mTOR Insensível à Rapamicina , Serina/metabolismo , Regulação para Cima
8.
Cancer Cell ; 41(5): 970-985.e3, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37084736

RESUMO

We analyzed 2,532 lung adenocarcinomas (LUAD) to identify the clinicopathological and genomic features associated with metastasis, metastatic burden, organotropism, and metastasis-free survival. Patients who develop metastasis are younger and male, with primary tumors enriched in micropapillary or solid histological subtypes and with a higher mutational burden, chromosomal instability, and fraction of genome doublings. Inactivation of TP53, SMARCA4, and CDKN2A are correlated with a site-specific shorter time to metastasis. The APOBEC mutational signature is more prevalent among metastases, particularly liver lesions. Analyses of matched specimens show that oncogenic and actionable alterations are frequently shared between primary tumors and metastases, whereas copy number alterations of unknown significance are more often private to metastases. Only 4% of metastases harbor therapeutically actionable alterations undetected in their matched primaries. Key clinicopathological and genomic alterations in our cohort were externally validated. In summary, our analysis highlights the complexity of clinicopathological features and tumor genomics in LUAD organotropism.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Masculino , Adenocarcinoma de Pulmão/genética , Mutação , Variações do Número de Cópias de DNA , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Genômica , DNA Helicases/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética
9.
Cell Rep ; 41(11): 111818, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36516772

RESUMO

Oncogenic KRas activates mitochondrial fission through Erk-mediated phosphorylation of the mitochondrial fission GTPase Drp1. Drp1 deletion inhibits tumorigenesis of KRas-driven pancreatic cancer, but the role of mitochondrial dynamics in other Ras-driven malignancies is poorly defined. Here we show that in vitro and in vivo growth of KRas-driven lung adenocarcinoma is unaffected by deletion of Drp1 but is inhibited by deletion of Opa1, the GTPase that regulates inner membrane fusion and proper cristae morphology. Mechanistically, Opa1 knockout disrupts cristae morphology and inhibits electron transport chain (ETC) assembly and activity, which inhibits tumor cell proliferation through loss of NAD+ regeneration. Simultaneous inactivation of Drp1 and Opa1 restores cristae morphology, ETC activity, and cell proliferation indicating that mitochondrial fission activity drives ETC dysfunction induced by Opa1 knockout. Our results support a model in which mitochondrial fission events disrupt cristae structure, and tumor cells with hyperactive fission activity require Opa1 activity to maintain ETC function.


Assuntos
Adenocarcinoma de Pulmão , NAD , Humanos , NAD/metabolismo , Mitocôndrias/metabolismo , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Membranas Mitocondriais/metabolismo , Dinâmica Mitocondrial , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Dinaminas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
10.
Sci Transl Med ; 14(665): eabo1050, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36197962

RESUMO

About 50% of patients with early-stage, surgically resected lung cancer will develop distant metastasis. There remains an unmet need to identify patients likely to develop recurrence and to design innovative therapies to decrease this risk. Two primary isoforms of BRMS1, v1 and v2, are present in humans. Using next-generation sequencing of BRMS1 on matched human noncancerous lung tissue and non-small cell lung cancer (NSCLC) specimens, we identified single-nucleotide polymorphism (SNP) rs1052566 that results in an A273V mutation of BRMS1v2. This SNP is homozygous (BRMS1v2A273V/A273V) in 8% of the population and correlates with aggressive biology in lung adenocarcinoma (LUAD). Mechanistically, we show that BRMS1v2 A273V abolishes the metastasis suppressor function of BRMS1v2 and promotes robust cell invasion and metastases by activation of c-fos-mediated gene-specific transcriptional regulation. BRMS1v2 A273V increases cell invasion in vitro and increases metastases in both tail-vein injection xenografts and LUAD patient-derived organoid (PDO) intracardiac injection metastasis in vivo models. Moreover, we show that BRMS1v2 A273V fails to interact with nuclear Src, thereby activating intratumoral c-fos in vitro. Higher c-fos results in up-regulation of CEACAM6, which drives metastases in vitro and in vivo. Using both xenograft and PDO metastasis models, we repurposed T5224 for treatment, a c-fos pharmacologic inhibitor investigated in clinical trials for arthritis, and observed suppression of metastases in BRMS1v2A273V/A273V LUAD in mice. Collectively, we elucidate the mechanism of BRMS1v2A273V/A273V-induced metastases and offer a putative therapeutic strategy for patients with LUAD who have this germline alteration.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Células Germinativas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas Repressoras/metabolismo , Polimorfismo de Nucleotídeo Único
11.
Biomolecules ; 12(11)2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36358918

RESUMO

In the past decade, defective DNA repair has been increasingly linked with cancer progression. Human tumors with markers of defective DNA repair and increased replication stress exhibit genomic instability and poor survival rates across tumor types. Seminal studies have demonstrated that genomic instability develops following inactivation of BRCA1, BRCA2, or BRCA-related genes. However, it is recognized that many tumors exhibit genomic instability but lack BRCA inactivation. We sought to identify a pan-cancer mechanism that underpins genomic instability and cancer progression in BRCA-wildtype tumors. Methods: Using multi-omics data from two independent consortia, we analyzed data from dozens of tumor types to identify patient cohorts characterized by poor outcomes, genomic instability, and wildtype BRCA genes. We developed several novel metrics to identify the genetic underpinnings of genomic instability in tumors with wildtype BRCA. Associated clinical data was mined to analyze patient responses to standard of care therapies and potential differences in metastatic dissemination. Results: Systematic analysis of the DNA repair landscape revealed that defective single-strand break repair, translesion synthesis, and non-homologous end-joining effectors drive genomic instability in tumors with wildtype BRCA and BRCA-related genes. Importantly, we find that loss of these effectors promotes replication stress, therapy resistance, and increased primary carcinoma to brain metastasis. Conclusions: Our results have defined a new pan-cancer class of tumors characterized by replicative instability (RIN). RIN is defined by the accumulation of intra-chromosomal, gene-level gain and loss events at replication stress sensitive (RSS) genome sites. We find that RIN accelerates cancer progression by driving copy number alterations and transcriptional program rewiring that promote tumor evolution. Clinically, we find that RIN drives therapy resistance and distant metastases across multiple tumor types.


Assuntos
Instabilidade Genômica , Neoplasias , Humanos , Reparo do DNA/genética , Reparo do DNA por Junção de Extremidades , Neoplasias/genética , Replicação do DNA , Aberrações Cromossômicas
12.
JAMA Surg ; 156(2): e205601, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33355651

RESUMO

Importance: Recommendations for adjuvant therapy after surgical resection of lung adenocarcinoma (LUAD) are based solely on TNM classification but are agnostic to genomic and high-risk clinicopathologic factors. Creation of a prediction model that integrates tumor genomic and clinicopathologic factors may better identify patients at risk for recurrence. Objective: To identify tumor genomic factors independently associated with recurrence, even in the presence of aggressive, high-risk clinicopathologic variables, in patients with completely resected stages I to III LUAD, and to develop a computational machine-learning prediction model (PRecur) to determine whether the integration of genomic and clinicopathologic features could better predict risk of recurrence, compared with the TNM system. Design, Setting, and Participants: This prospective cohort study included 426 patients treated from January 1, 2008, to December 31, 2017, at a single large cancer center and selected in consecutive samples. Eligibility criteria included complete surgical resection of stages I to III LUAD, broad-panel next-generation sequencing data with matched clinicopathologic data, and no neoadjuvant therapy. External validation of the PRecur prediction model was performed using The Cancer Genome Atlas (TCGA). Data were analyzed from 2014 to 2018. Main Outcomes and Measures: The study end point consisted of relapse-free survival (RFS), estimated using the Kaplan-Meier approach. Associations among clinicopathologic factors, genomic alterations, and RFS were established using Cox proportional hazards regression. The PRecur prediction model integrated genomic and clinicopathologic factors using gradient-boosting survival regression for risk group generation and prediction of RFS. A concordance probability estimate (CPE) was used to assess the predictive ability of the PRecur model. Results: Of the 426 patients included in the analysis (286 women [67%]; median age at surgery, 69 [interquartile range, 62-75] years), 318 (75%) had stage I cancer. Association analysis showed that alterations in SMARCA4 (clinicopathologic-adjusted hazard ratio [HR], 2.44; 95% CI, 1.03-5.77; P = .042) and TP53 (clinicopathologic-adjusted HR, 1.73; 95% CI, 1.09-2.73; P = .02) and the fraction of genome altered (clinicopathologic-adjusted HR, 1.03; 95% CI, 1.10-1.04; P = .005) were independently associated with RFS. The PRecur prediction model outperformed the TNM-based model (CPE, 0.73 vs 0.61; difference, 0.12 [95% CI, 0.05-0.19]; P < .001) for prediction of RFS. To validate the prediction model, PRecur was applied to the TCGA LUAD data set (n = 360), and a clear separation of risk groups was noted (log-rank statistic, 7.5; P = .02), confirming external validation. Conclusions and Relevance: The findings suggest that integration of tumor genomics and clinicopathologic features improves risk stratification and prediction of recurrence after surgical resection of early-stage LUAD. Improved identification of patients at risk for recurrence could enrich and enhance accrual to adjuvant therapy clinical trials.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Adenocarcinoma/cirurgia , Idoso , Feminino , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco
13.
BMC Bioinformatics ; 11: 396, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-20653935

RESUMO

BACKGROUND: In the last decade, biochemical studies have revealed that epigenetic modifications including histone modifications, histone variants and DNA methylation form a complex network that regulate the state of chromatin and processes that depend on it including transcription and DNA replication. Currently, a large number of these epigenetic modifications are being mapped in a variety of cell lines at different stages of development using high throughput sequencing by members of the ENCODE consortium, the NIH Roadmap Epigenomics Program and the Human Epigenome Project. An extremely promising and underexplored area of research is the application of machine learning methods, which are designed to construct predictive network models, to these large-scale epigenomic data sets. RESULTS: Using a ChIP-Seq data set of 20 histone lysine and arginine methylations and histone variant H2A.Z in human CD4+ T-cells, we built predictive models of gene expression as a function of histone modification/variant levels using Multilinear (ML) Regression and Multivariate Adaptive Regression Splines (MARS). Along with extensive crosstalk among the 20 histone methylations, we found H4R3me2 was the most and second most globally repressive histone methylation among the 20 studied in the ML and MARS models, respectively. In support of our finding, a number of experimental studies show that PRMT5-catalyzed symmetric dimethylation of H4R3 is associated with repression of gene expression. This includes a recent study, which demonstrated that H4R3me2 is required for DNMT3A-mediated DNA methylation--a known global repressor of gene expression. CONCLUSION: In stark contrast to univariate analysis of the relationship between H4R3me2 and gene expression levels, our study showed that the regulatory role of some modifications like H4R3me2 is masked by confounding variables, but can be elucidated by multivariate/systems-level approaches.


Assuntos
Inteligência Artificial , Epigênese Genética , Histonas/metabolismo , Arginina/metabolismo , Sequência de Bases , Linfócitos T CD4-Positivos , Expressão Gênica , Humanos , Lisina/metabolismo , Metilação , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Metiltransferases/metabolismo , Processamento de Proteína Pós-Traducional
14.
Mol Cancer ; 9: 104, 2010 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-20459822

RESUMO

BACKGROUND: Intestinal cell kinase (ICK; GeneID 22858) is a conserved MAPK and CDK-like kinase that is widely expressed in human tissues. Data from the Cancer Genome Anatomy Project indicated ICK mRNA is increased in cancer, and that its expression correlated with expression of mRNA for an uncharacterized F-box protein, FBX9 (GeneID: 26268). ICK and FBX9 genes are arranged head-to-head on opposite strands, with start sites for transcription separated by approximately 3.3 kb. We hypothesized ICK and FBX9 are potentially important genes in cancer controlled by a bidirectional promoter. RESULTS: We assessed promoter activity of the intergenic region in both orientations in cancer cell lines derived from breast (AU565, SKBR3), colon (HCT-15, KM12), and stomach (AGS) cancers, as well as in embryonic human kidney (HEK293T) cells. The intergenic segment was active in both orientations in all of these lines, and ICK promoter activity was greater than FBX9 promoter activity. Results from deletions and truncations defined a minimal promoter for ICK, and revealed that repressors and enhancers differentially regulate ICK versus FBX9 promoter activity. The ICK promoter contains consensus motifs for several FOX-family transcription factors that align when mouse and human are compared using EMBOSS. FOXA1 and FOXA2 increase luciferase activity of a minimal promoter 10-20 fold in HEK293T cells. Consensus sites for TCF7L2 (TCF4) (Gene Id: 6934) are also present in both mouse and human. The expression of beta-catenin increased activity of the minimal promoter approximately 10 fold. ICK reference mRNAs (NM_014920.3, NM_016513) are expressed in low copy number and increased in some breast cancers, using a ten base tag 5'-TCAACCTTAT-3' specific for both ICK transcripts. CONCLUSION: ICK and FBX9 are divergently transcribed from a bidirectional promoter that is GC-rich and contains a CpG island. A minimal promoter for ICK contains functional sites for beta-catenin/TCF7L2 and FOXA. These data are consistent with functions that have been proposed for ICK in development and in proliferation or survival of some breast and colon cancers.


Assuntos
Proteínas F-Box/genética , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica/genética , Regiões Promotoras Genéticas/genética , Proteínas Serina-Treonina Quinases/genética , Fatores de Transcrição TCF/genética , Animais , Sequência de Bases , Western Blotting , Linhagem Celular Tumoral , Sequência Consenso , Sequência Conservada , Proteínas F-Box/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Proteínas Serina-Treonina Quinases/metabolismo , Alinhamento de Sequência , Fatores de Transcrição TCF/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição , beta Catenina/genética , beta Catenina/metabolismo
15.
Cancer Res ; 80(5): 950-963, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31900260

RESUMO

DRAIC is a 1.7 kb spliced long noncoding RNA downregulated in castration-resistant advanced prostate cancer. Decreased DRAIC expression predicts poor patient outcome in prostate and seven other cancers, while increased DRAIC represses growth of xenografted tumors. Here, we show that cancers with decreased DRAIC expression have increased NF-κB target gene expression. DRAIC downregulation increased cell invasion and soft agar colony formation; this was dependent on NF-κB activation. DRAIC interacted with subunits of the IκB kinase (IKK) complex to inhibit their interaction with each other, the phosphorylation of IκBα, and the activation of NF-κB. These functions of DRAIC mapped to the same fragment containing bases 701-905. Thus, DRAIC lncRNA inhibits prostate cancer progression through suppression of NF-κB activation by interfering with IKK activity. SIGNIFICANCE: A cytoplasmic tumor-suppressive lncRNA interacts with and inhibits a major kinase that activates an oncogenic transcription factor in prostate cancer. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/5/950/F1.large.jpg.


Assuntos
Regulação Neoplásica da Expressão Gênica , Quinase I-kappa B/genética , NF-kappa B/metabolismo , Neoplasias da Próstata/genética , RNA Longo não Codificante/metabolismo , Animais , Linhagem Celular Tumoral , Progressão da Doença , Regulação para Baixo , Humanos , Quinase I-kappa B/antagonistas & inibidores , Quinase I-kappa B/metabolismo , Masculino , Camundongos , Fosforilação/genética , Próstata/patologia , Neoplasias da Próstata/patologia , RNA Longo não Codificante/genética , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Cancer Res ; 80(21): 4791-4804, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32855208

RESUMO

The majority of clinical deaths in patients with triple-negative breast cancer (TNBC) are due to chemoresistance and aggressive metastases, with high prevalence in younger women of African ethnicity. Although tumorigenic drivers are numerous and varied, the drivers of metastatic transition remain largely unknown. Here, we uncovered a molecular dependence of TNBC tumors on the TRIM37 network, which enables tumor cells to resist chemotherapeutic as well as metastatic stress. TRIM37-directed histone H2A monoubiquitination enforces changes in DNA repair that rendered TP53-mutant TNBC cells resistant to chemotherapy. Chemotherapeutic drugs triggered a positive feedback loop via ATM/E2F1/STAT signaling, amplifying the TRIM37 network in chemoresistant cancer cells. High expression of TRIM37 induced transcriptomic changes characteristic of a metastatic phenotype, and inhibition of TRIM37 substantially reduced the in vivo propensity of TNBC cells. Selective delivery of TRIM37-specific antisense oligonucleotides using antifolate receptor 1-conjugated nanoparticles in combination with chemotherapy suppressed lung metastasis in spontaneous metastatic murine models. Collectively, these findings establish TRIM37 as a clinically relevant target with opportunities for therapeutic intervention. SIGNIFICANCE: TRIM37 drives aggressive TNBC biology by promoting resistance to chemotherapy and inducing a prometastatic transcriptional program; inhibition of TRIM37 increases chemotherapy efficacy and reduces metastasis risk in patients with TNBC.


Assuntos
Resistencia a Medicamentos Antineoplásicos/fisiologia , Proteínas com Motivo Tripartido/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Front Oncol ; 10: 585551, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33489883

RESUMO

It has long been recognized that defects in cell cycle checkpoint and DNA repair pathways give rise to genomic instability, tumor heterogeneity, and metastasis. Despite this knowledge, the transcription factor-mediated gene expression programs that enable survival and proliferation in the face of enormous replication stress and DNA damage have remained elusive. Using robust omics data from two independent studies, we provide evidence that a large cohort of lung adenocarcinomas exhibit significant genome instability and overexpress the DNA damage responsive transcription factor MYB proto-oncogene like 2 (MYBL2). Across two studies, elevated MYBL2 expression was a robust marker of poor overall survival and disease-free survival outcomes, regardless of disease stage. Clinically, elevated MYBL2 expression identified patients with aggressive early onset disease, increased lymph node involvement, and increased incidence of distant metastases. Analysis of genomic sequencing data demonstrated that MYBL2 High lung adenocarcinomas had elevated somatic mutation burden, widespread chromosomal alterations, and alterations in single-strand DNA break repair pathways. In this study, we provide evidence that impaired single-strand break repair, combined with a loss of cell cycle regulators TP53 and RB1, give rise to MYBL2-mediated transcriptional programs. Omics data supports a model wherein tumors with significant genomic instability upregulate MYBL2 to drive genes that control replication stress responses, promote error-prone DNA repair, and antagonize faithful homologous recombination repair. Our study supports the use of checkpoint kinase 1 (CHK1) pharmacological inhibitors, in targeted MYBL2 High patient cohorts, as a future therapy to improve lung adenocarcinoma patient outcomes.

18.
J Thorac Oncol ; 15(12): 1844-1856, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32791233

RESUMO

INTRODUCTION: The purpose of the study is to genomically characterize the biology and related therapeutic opportunities of prognostically important predominant histologic subtypes in lung adenocarcinoma (LUAD). METHODS: We identified 604 patients with stage I to III LUAD who underwent complete resection and targeted next-generation sequencing using the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets platform. Tumors were classified according to predominant histologic subtype and grouped by architectural grade (lepidic [LEP], acinar or papillary [ACI/PAP], and micropapillary or solid [MIP/SOL]). Associations among clinicopathologic factors, genomic features, mutational signatures, and recurrence were evaluated within subtypes and, when appropriate, quantified using competing-risks regression, with adjustment for pathologic stage and extent of resection. RESULTS: MIP/SOL tumors had higher tumor mutational burden (p < 0.001), fraction of genome altered (p = 0.001), copy number amplifications (p = 0.021), rate of whole-genome doubling (p = 0.008), and number of oncogenic pathways altered ( p < 0.001) as compared with LEP and ACI/PAP tumors. Across all tumors, mutational signatures attributed to APOBEC activity were associated with the highest risk of postresection recurrence: SBS2 (p = 0.021) and SBS13 (p = 0.005). Three oncogenic pathways (p53, Wnt, Myc) were altered with statistical significance in MIP/SOL tumors. Compared with LEP and ACI/PAP tumors, MIP/SOL tumors had a higher frequency of targetable BRAF-V600E mutations (p = 0.046). Among ACI/PAP tumors, alterations in the cell cycle (p < 0.001) and PI3K (p = 0.002) pathways were associated with recurrence; among MIP/SOL tumors, only PI3K alterations were associated with recurrence (p = 0.049). CONCLUSIONS: These results provide the first in-depth assessment of tumor genomic profiling of predominant LUAD histologic subtypes, their associations with recurrence, and their correlation with targetable driver alterations in patients with surgically resected LUAD.


Assuntos
Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Idoso , Feminino , Genômica , Humanos , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Mutação , Recidiva Local de Neoplasia/genética , Prognóstico
19.
Mol Cell Biol ; 26(2): 457-71, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16382138

RESUMO

Over the last several years, significant progress has been made in identifying chromatin-regulated events that govern NF-kappaB transcription. Using either laminin attachment or tumor necrosis factor alpha as a physiological stimulus of NF-kappaB activation, we demonstrate that IkappaB kinase alpha (IKKalpha) is recruited to chromatin in distinct phases. In the initial phase, IKKalpha is responsible for derepressing the silencing mediator for retinoic acid and thyroid hormone receptor (SMRT)-histone deacetylase 3 (HDAC3) corepressor complex from the p50 homodimer. However, in the latter phase, chromatin-bound IKKalpha coordinates the simultaneous phosphorylation of RelA/p65(S536) and SMRT(S2410) as detected by chromatin immunoprecipitation (ChIP) assays. Although phosphorylated SMRT remains bound to the active p50-RelA/p65 heterodimer of NF-kappaB, derepression of SMRT is evidenced by the loss of chromatin-associated HDAC3 activity. ChIP and re-ChIP analysis demonstrates that phosphorylation of RelA/p65(S536) and SMRT(S2410) occurs prior to acetylation of RelA/p65 at K310. Moreover, IKKalpha-induced phosphorylation of RelA/p65(S536) displaces corepressor activity, allowing p300-mediated acetylation of RelA/p65. Introduction of nonphosphorylatable mutants of RelA/p65 and SMRT proteins or the inhibition of IKK activity results in active repression of NF-kappaB promoters by tethering the SMRT-HDAC3 complex. Similar to phosphorylation within the Rel homology domain of RelA/p65, which governs an exchange of HDAC1 for CBP/p300 acetyltransferases, we demonstrate that phosphorylation within the transactivation domain of RelA/p65(S536) displaces SMRT-HDAC3 repressor activity, allowing p300 to acetylate RelA/p65.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Quinase I-kappa B/metabolismo , Proteínas Repressoras/metabolismo , Fator de Transcrição RelA/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Linhagem Celular , Cromatina/metabolismo , Histona Desacetilases/metabolismo , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Correpressor 2 de Receptor Nuclear , Fosforilação , Regiões Promotoras Genéticas , Transcrição Gênica
20.
Cancer Cell ; 34(2): 331-345.e11, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-30107179

RESUMO

Therapeutic antibodies targeting ovarian cancer (OvCa)-enriched receptors have largely been disappointing due to limited tumor-specific antibody-dependent cellular cytotoxicity. Here we report a symbiotic approach that is highly selective and superior compared with investigational clinical antibodies. This bispecific-anchored cytotoxicity activator antibody is rationally designed to instigate "cis" and "trans" cytotoxicity by combining specificities against folate receptor alpha-1 (FOLR1) and death receptor 5 (DR5). Whereas the in vivo agonist DR5 signaling requires FcγRIIB interaction, the FOLR1 anchor functions as a primary clustering point to retain and maintain a high level of tumor-specific apoptosis. The presented proof of concept study strategically makes use of a tumor cell-enriched anchor receptor for agonist death receptor targeting to potentially generate a clinically viable strategy for OvCa.


Assuntos
Anticorpos Biespecíficos/uso terapêutico , Receptor 1 de Folato/antagonistas & inibidores , Neoplasias Ovarianas/tratamento farmacológico , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/patologia , Receptores de IgG/fisiologia
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