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1.
PLoS Biol ; 18(8): e3000808, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817651

RESUMO

Although dysregulation of mitochondrial dynamics has been linked to cellular senescence, which contributes to advanced age-related disorders, it is unclear how Krüppel-like factor 5 (Klf5), an essential transcriptional factor of cardiovascular remodeling, mediates the link between mitochondrial dynamics and vascular smooth muscle cell (VSMC) senescence. Here, we show that Klf5 down-regulation in VSMCs is correlated with rupture of abdominal aortic aneurysm (AAA), an age-related vascular disease. Mice lacking Klf5 in VSMCs exacerbate vascular senescence and progression of angiotensin II (Ang II)-induced AAA by facilitating reactive oxygen species (ROS) formation. Klf5 knockdown enhances, while Klf5 overexpression suppresses mitochondrial fission. Mechanistically, Klf5 activates eukaryotic translation initiation factor 5a (eIF5a) transcription through binding to the promoter of eIF5a, which in turn preserves mitochondrial integrity by interacting with mitofusin 1 (Mfn1). Accordingly, decreased expression of eIF5a elicited by Klf5 down-regulation leads to mitochondrial fission and excessive ROS production. Inhibition of mitochondrial fission decreases ROS production and VSMC senescence. Our studies provide a potential therapeutic target for age-related vascular disorders.


Assuntos
Aneurisma da Aorta Abdominal/genética , Células Endoteliais/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Mitocôndrias/metabolismo , Fatores de Iniciação de Peptídeos/genética , Proteínas de Ligação a RNA/genética , Idoso , Angiotensina II/genética , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Aorta/diagnóstico por imagem , Aorta/metabolismo , Aorta/patologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/patologia , Senescência Celular/efeitos dos fármacos , Ecocardiografia , Células Endoteliais/patologia , Feminino , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/deficiência , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/patologia , Dinâmica Mitocondrial/efeitos dos fármacos , Fatores de Iniciação de Peptídeos/deficiência , Cultura Primária de Células , Regiões Promotoras Genéticas , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo
2.
J Clin Pathol ; 73(9): 527-530, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32699115

RESUMO

The GLIS 1-3 genes belong to a family of transcription factors, the Krüppel-like zinc finger proteins. The GLIS proteins function primarily as activators of transcription (GLIS 1 and 3), while GLIS 2 functions as a repressor. Collectively, the GLIS proteins are involved in a variety of diseases in several organs ranging from Alzheimer's disease, facial dysmorphism, neonatal diabetes mellitus, breast and colon cancers and leukaemia. In particular, loss-of-function mutations in GLIS2 are responsible for an autosomal recessive cystic kidney disease called nephronophthisis, which is characterised by tubular atrophy, interstitial fibrosis and corticomedullary cysts.Of diagnostic value in current practice are the presence of GLIS 3 and 1 fusions with PAX8 in almost 100% of hyalinising trabecular tumours of the thyroid gland. This enables its separation from papillary thyroid cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Fatores de Transcrição Kruppel-Like/genética , Proteínas Repressoras/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Transativadores/genética , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/metabolismo , Fusão Gênica , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Mutação com Perda de Função , Fator de Transcrição PAX8/genética , Fator de Transcrição PAX8/metabolismo , Proteínas Repressoras/metabolismo , Glândula Tireoide/patologia , Transativadores/metabolismo , Fatores de Transcrição/metabolismo
3.
Nat Commun ; 11(1): 2922, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32523103

RESUMO

The conversion of white adipocytes to thermogenic beige adipocytes represents a potential mechanism to treat obesity and related metabolic disorders. However, the mechanisms involved in converting white to beige adipose tissue remain incompletely understood. Here we show profound beiging in a genetic mouse model lacking the transcriptional repressor Krüppel-like factor 3 (KLF3). Bone marrow transplants from these animals confer the beige phenotype on wild type recipients. Analysis of the cellular and molecular changes reveal an accumulation of eosinophils in adipose tissue. We examine the transcriptomic profile of adipose-resident eosinophils and posit that KLF3 regulates adipose tissue function via transcriptional control of secreted molecules linked to beiging. Furthermore, we provide evidence that eosinophils may directly act on adipocytes to drive beiging and highlight the critical role of these little-understood immune cells in thermogenesis.


Assuntos
Tecido Adiposo/metabolismo , Eosinófilos/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Transdução de Sinais/fisiologia , Adiposidade/genética , Adiposidade/fisiologia , Animais , Células COS , Chlorocebus aethiops , Imunoprecipitação da Cromatina , Citometria de Fluxo , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Obesidade/metabolismo , Transdução de Sinais/genética , Software
4.
Proc Natl Acad Sci U S A ; 117(27): 15673-15683, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571933

RESUMO

Stemness encompasses the capability of a cell for self-renewal and differentiation. The stem cell maintains a balance between proliferation, quiescence, and regeneration via interactions with the microenvironment. Previously, we showed that ectopic expression of the mitochondrial ribosomal protein S18-2 (MRPS18-2) led to immortalization of primary fibroblasts, accompanied by induction of an embryonic stem cell (ESC) phenotype. Moreover, we demonstrated interaction between S18-2 and the retinoblastoma-associated protein (RB) and hypothesized that the simultaneous expression of RB and S18-2 is essential for maintaining cell stemness. Here, we experimentally investigated the role of S18-2 in cell stemness and differentiation. Concurrent expression of RB and S18-2 resulted in immortalization of Rb1 -/- primary mouse embryonic fibroblasts and in aggressive tumor growth in severe combined immunodeficiency mice. These cells, which express both RB and S18-2 at high levels, exhibited the potential to differentiate into various lineages in vitro, including osteogenic, chondrogenic, and adipogenic lineages. Mechanistically, S18-2 formed a multimeric protein complex with prohibitin and the ring finger protein 2 (RNF2). This molecular complex increased the monoubiquitination of histone H2ALys119, a characteristic trait of ESCs, by enhanced E3-ligase activity of RNF2. Furthermore, we found enrichment of KLF4 at the S18-2 promoter region and that the S18-2 expression is positively correlated with KLF4 levels. Importantly, knockdown of S18-2 in zebrafish larvae led to embryonic lethality. Collectively, our findings suggest an important role for S18-2 in cell stemness and differentiation and potentially also in cancerogenesis.


Assuntos
Mitocôndrias/genética , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas de Ligação a Retinoblastoma/genética , Proteínas Ribossômicas/genética , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Autorrenovação Celular/genética , Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Histonas/genética , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Mitocôndrias/metabolismo , Complexo Repressor Polycomb 1/genética , Proteínas Ribossômicas/química , Microambiente Tumoral/genética , Ubiquitina-Proteína Ligases/genética
5.
Gene ; 752: 144782, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32442577

RESUMO

The branched-chain amino acids (BCAA) play an important role in muscle energy metabolism, and Krüppel-like factor 15 (KLF15) is an essential regulator of BCAA metabolism in muscle under nutritional deficiency. In this study, we analyzed the effect of normal feeding (starvation for 0 day), starvation for 3, 7, 10, 15 days, and refeeding for 7 days after 15 days of starvation on the expression of KLF15 and BCAA metabolism in muscle of Chinese soft-shelled turtles by a fasting-refeeding trial. The results showed that the level of KLF15 transcription was increased first and then decreased in muscle during short-term starvation, and the protein level was gradually increased. Both the mRNA and protein level of the KLF15 returned to normal feeding level after refeeding for 7 days. The changing trend of the activities of branched-chain aminotransferase (BCAT) and alanine aminotransferase (ALT) was consistent to that of KLF15 mRNA, but at the transcription level, the expression of BCAT mRNA was consistent with the change of enzyme activity as well as ALT continued to increase in muscle under starvation. In addition, BCAA content showed a trend that decreased first and then increased under starvation, while the alanine (Ala) was the contrary. The above results indicated that the regulatory role of KLF15 in BCAA catabolism of muscle in Chinese soft-shelled turtles under nutritional deficiency, which might be activated the catabolism of BCAA in muscle to provide energy and maintain the homeostasis by KLF15-BACC signaling axis.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Músculo Esquelético/metabolismo , Alanina Transaminase/metabolismo , Aminoácidos de Cadeia Ramificada/genética , Animais , Metabolismo Energético/fisiologia , Jejum , Fatores de Transcrição Kruppel-Like/genética , Músculos/metabolismo , Transdução de Sinais/fisiologia , Inanição/metabolismo , Tartarugas/genética , Tartarugas/metabolismo
6.
Mol Genet Genomics ; 295(4): 1013-1026, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32363570

RESUMO

Obesity, a risk factor for multiple diseases (e.g. diabetes, hypertension, cancers) originates through complex interactions between genes and prevailing environment (food habit and lifestyle) that varies across populations. Indians exhibit a unique obesity phenotype with high abdominal adiposity for a given body weight compared to matched white populations suggesting presence of population-specific genetic and environmental factors influencing obesity. However, Indian population-specific genetic contributors for obesity have not been explored yet. Therefore, to identify potential genetic contributors, we performed a two-staged genome-wide association study (GWAS) for body mass index (BMI), a common measure to evaluate obesity in 5973 Indian adults and the lead findings were further replicated in 1286 Indian adolescents. Our study revealed novel association of variants-rs6913677 in BAI3 gene (p = 1.08 × 10-8) and rs2078267 in SLC22A11 gene (p = 4.62 × 10-8) at GWAS significance, and of rs8100011 in ZNF45 gene (p = 1.04 × 10-7) with near GWAS significance. As genetic loci may dictate the phenotype through modulation of epigenetic processes, we overlapped genetic data of identified signals with their DNA methylation patterns in 236 Indian individuals and performed methylation quantitative trait loci (meth-QTL) analysis. Further, functional roles of discovered variants and underlying genes were speculated using publicly available gene regulatory databases (ENCODE, JASPAR, GeneHancer, GTEx). The identified variants in BAI3 and SLC22A11 genes were found to dictate methylation patterns at unique CpGs harboring critical cis-regulatory elements. Further, BAI3, SLC22A11 and ZNF45 variants were located in repressive chromatin, active enhancer, and active chromatin regions, respectively, in human subcutaneous adipose tissue in ENCODE database. Additionally, these genomic regions represented potential binding sites for key transcription factors implicated in obesity and/or metabolic disorders. Interestingly, GTEx portal identify rs8100011 as a robust cis-expression quantitative trait locus (cis-eQTL) in subcutaneous adipose tissue (p = 1.6 × 10-7), and ZNF45 gene expression in skeletal muscle of Indian subjects showed an inverse correlation with BMI indicating its possible role in obesity. In conclusion, our study discovered 3 novel population-specific functional genetic variants (rs6913677, rs2078267, rs8100011) in 2 novel (SLC22A11 and ZNF45) and 1 earlier reported gene (BAI3) for BMI in Indians. Our study decodes key genomic loci underlying obesity phenotype in Indians that may serve as prospective drug targets in future.


Assuntos
Estudo de Associação Genômica Ampla , Fatores de Transcrição Kruppel-Like/genética , Obesidade/genética , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , Proteínas Repressoras/genética , Adolescente , Adulto , Grupo com Ancestrais do Continente Asiático/genética , Índice de Massa Corporal , Metilação de DNA , Feminino , Interação Gene-Ambiente , Predisposição Genética para Doença , Humanos , Índios Norte-Americanos/genética , Masculino , Obesidade/patologia , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Sequências Reguladoras de Ácido Nucleico/genética , Adulto Jovem
7.
Nat Commun ; 11(1): 2364, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398665

RESUMO

Human pluripotent stem cells (hPSCs) have the capacity to give rise to all differentiated cells of the adult. TGF-beta is used routinely for expansion of conventional hPSCs as flat epithelial colonies expressing the transcription factors POU5F1/OCT4, NANOG, SOX2. Here we report a global analysis of the transcriptional programme controlled by TGF-beta followed by an unbiased gain-of-function screening in multiple hPSC lines to identify factors mediating TGF-beta activity. We identify a quartet of transcriptional regulators promoting hPSC self-renewal including ZNF398, a human-specific mediator of pluripotency and epithelial character in hPSCs. Mechanistically, ZNF398 binds active promoters and enhancers together with SMAD3 and the histone acetyltransferase EP300, enabling transcription of TGF-beta targets. In the context of somatic cell reprogramming, inhibition of ZNF398 abolishes activation of pluripotency and epithelial genes and colony formation. Our findings have clear implications for the generation of bona fide hPSCs for regenerative medicine.


Assuntos
Autorrenovação Celular/genética , Regulação da Expressão Gênica/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Fatores de Transcrição Kruppel-Like/metabolismo , Animais , Linhagem Celular , Reprogramação Celular/genética , Células-Tronco Embrionárias , Elementos Facilitadores Genéticos/genética , Mutação com Ganho de Função , Técnicas de Silenciamento de Genes , Humanos , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Regiões Promotoras Genéticas/genética , RNA Interferente Pequeno/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Dedos de Zinco
8.
Proc Natl Acad Sci U S A ; 117(22): 12341-12351, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32430335

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with a dismal prognosis. Currently, there is no effective therapy for PDAC, and a detailed molecular and functional evaluation of PDACs is needed to identify and develop better therapeutic strategies. Here we show that the transcription factor Krüppel-like factor 7 (KLF7) is overexpressed in PDACs, and that inhibition of KLF7 blocks PDAC tumor growth and metastasis in cell culture and in mice. KLF7 expression in PDACs can be up-regulated due to activation of a MAP kinase pathway or inactivation of the tumor suppressor p53, two alterations that occur in a large majority of PDACs. ShRNA-mediated knockdown of KLF7 inhibits the expression of IFN-stimulated genes (ISGs), which are necessary for KLF7-mediated PDAC tumor growth and metastasis. KLF7 knockdown also results in the down-regulation of Discs Large MAGUK Scaffold Protein 3 (DLG3), resulting in Golgi complex fragmentation, and reduced protein glycosylation, leading to reduced secretion of cancer-promoting growth factors, such as chemokines. Genetic or pharmacologic activation of Golgi complex fragmentation blocks PDAC growth and metastasis similar to KLF7 inhibition. Our results demonstrate a therapeutically amenable, KLF7-driven pathway that promotes PDAC growth and metastasis by activating ISGs and maintaining Golgi complex integrity.


Assuntos
Complexo de Golgi/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Pancreáticas/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Complexo de Golgi/genética , Humanos , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Camundongos Knockout , Metástase Neoplásica , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/fisiopatologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Nucleic Acids Res ; 48(11): 5986-6000, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32406922

RESUMO

Our study focuses on a family of ubiquitously expressed human C2H2 zinc finger proteins comprised of ZFX, ZFY and ZNF711. Although their protein structure suggests that ZFX, ZFY and ZNF711 are transcriptional regulators, the mechanisms by which they influence transcription have not yet been elucidated. We used CRISPR-mediated deletion to create bi-allelic knockouts of ZFX and/or ZNF711 in female HEK293T cells (which naturally lack ZFY). We found that loss of either ZFX or ZNF711 reduced cell growth and that the double knockout cells have major defects in proliferation. RNA-seq analysis revealed that thousands of genes showed altered expression in the double knockout clones, suggesting that these TFs are critical regulators of the transcriptome. To gain insight into how these TFs regulate transcription, we created mutant ZFX proteins and analyzed them for DNA binding and transactivation capability. We found that zinc fingers 11-13 are necessary and sufficient for DNA binding and, in combination with the N terminal region, constitute a functional transactivator. Our functional analyses of the ZFX family provides important new insights into transcriptional regulation in human cells by members of the large, but under-studied family of C2H2 zinc finger proteins.


Assuntos
Ilhas de CpG/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Regiões Promotoras Genéticas , Sítio de Iniciação de Transcrição , Alelos , Pareamento de Bases , Sequência de Bases , Proteínas de Ligação a DNA/genética , Feminino , Deleção de Genes , Células HEK293 , Humanos , Fatores de Transcrição Kruppel-Like/genética , Masculino , Transcriptoma , Dedos de Zinco
10.
Nat Commun ; 11(1): 2020, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332753

RESUMO

The functional consequences of somatic non-coding mutations in ovarian cancer (OC) are unknown. To identify regulatory elements (RE) and genes perturbed by acquired non-coding variants, here we establish epigenomic and transcriptomic landscapes of primary OCs using H3K27ac ChIP-seq and RNA-seq, and then integrate these with whole genome sequencing data from 232 OCs. We identify 25 frequently mutated regulatory elements, including an enhancer at 6p22.1 which associates with differential expression of ZSCAN16 (P = 6.6 × 10-4) and ZSCAN12 (P = 0.02). CRISPR/Cas9 knockout of this enhancer induces downregulation of both genes. Globally, there is an enrichment of single nucleotide variants in active binding sites for TEAD4 (P = 6 × 10-11) and its binding partner PAX8 (P = 2×10-10), a known lineage-specific transcription factor in OC. In addition, the collection of cis REs associated with PAX8 comprise the most frequently mutated set of enhancers in OC (P = 0.003). These data indicate that non-coding somatic mutations disrupt the PAX8 transcriptional network during OC development.


Assuntos
Carcinoma Epitelial do Ovário/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Neoplasias Ovarianas/genética , Fator de Transcrição PAX8/metabolismo , Adulto , Idoso , Sítios de Ligação/genética , Carcinoma Epitelial do Ovário/patologia , Sequenciamento de Cromatina por Imunoprecipitação , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Epigênese Genética , Epigenômica , Feminino , Técnicas de Inativação de Genes , Humanos , Fatores de Transcrição Kruppel-Like/genética , Pessoa de Meia-Idade , Proteínas Musculares/metabolismo , Mutação , Neoplasias Ovarianas/patologia , Ovário/patologia , Polimorfismo de Nucleotídeo Único , RNA-Seq , Proteínas Repressoras/genética , Fatores de Transcrição/metabolismo , Sequenciamento Completo do Genoma
11.
BMC Med Genet ; 21(1): 78, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293321

RESUMO

BACKGROUND: The protein Kruppel-like factor 13 (KLF13) is a member of the KLF family and has been identified as a cardiac transcription factor that is involved in heart development. However, the relationship between KLF13 variants and CHDs in humans remains largely unknown. The present study aimed to screen the KLF13 variants in CHD patients and genetically analyze the functions of these variants. METHODS: KLF13 variants were sequenced in a cohort of 309 CHD patients and population-matched healthy controls (n = 200) using targeted sequencing. To investigate the effect of variants on the functional properties of the KLF13 protein, the expression and subcellular localization of the protein, as well as the transcriptional activities of downstream genes and physical interactions with other transcription factors, were assessed. RESULTS: Two heterozygous variants, c.487C > T (P163S) and c.467G > A (S156N), were identified in two out of 309 CHD patients with tricuspid valve atresia and transposition of the great arteries, respectively. No variants were found among healthy controls. The variant c.467G > A (S156N) had increased protein expression and enhanced functionality compared with the wild type, without affecting the subcellular localization. The other variant, c.487C > T (P163S), did not show any abnormalities in protein expression or subcellular localization; however, it inhibited the transcriptional activities of downstream target genes and physically interacted with TBX5, another cardiac transcription factor. CONCLUSION: Our results show that the S156N and P163S variants may affect the transcriptional function of KLF13 and physical interaction with TBX5. These results identified KLF13 as a potential genetic risk factor for congenital heart disease.


Assuntos
Proteínas de Ciclo Celular/genética , Cardiopatias Congênitas/genética , Fatores de Transcrição Kruppel-Like/genética , Proteínas Repressoras/genética , Proteínas com Domínio T/genética , Atresia Tricúspide/genética , Criança , Pré-Escolar , Feminino , Regulação da Expressão Gênica/genética , Coração/fisiopatologia , Cardiopatias Congênitas/fisiopatologia , Heterozigoto , Humanos , Lactente , Recém-Nascido , Masculino , Polimorfismo de Nucleotídeo Único/genética , Transposição dos Grandes Vasos/metabolismo , Transposição dos Grandes Vasos/fisiopatologia , Atresia Tricúspide/fisiopatologia
12.
Nat Commun ; 11(1): 1185, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32132543

RESUMO

Pulmonary arterial hypertension (PAH) is a severe disorder of lung vasculature that causes right heart failure. Homoeostatic effects of flow-activated transcription factor Krüppel-like factor 2 (KLF2) are compromised in PAH. Here, we show that KLF2-induced exosomal microRNAs, miR-181a-5p and miR-324-5p act together to attenuate pulmonary vascular remodelling and that their actions are mediated by Notch4 and ETS1 and other key regulators of vascular homoeostasis. Expressions of KLF2, miR-181a-5p and miR-324-5p are reduced, while levels of their target genes are elevated in pre-clinical PAH, idiopathic PAH and heritable PAH with missense p.H288Y KLF2 mutation. Therapeutic supplementation of miR-181a-5p and miR-324-5p reduces proliferative and angiogenic responses in patient-derived cells and attenuates disease progression in PAH mice. This study shows that reduced KLF2 signalling is a common feature of human PAH and highlights the potential therapeutic role of KLF2-regulated exosomal miRNAs in PAH and other diseases associated with vascular remodelling.


Assuntos
Terapia Genética/métodos , Fatores de Transcrição Kruppel-Like/metabolismo , MicroRNAs/uso terapêutico , Hipertensão Arterial Pulmonar/terapia , Adulto , Idoso , Animais , Proliferação de Células/genética , Modelos Animais de Doenças , Progressão da Doença , Células Endoteliais , Exossomos/genética , Exossomos/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Fatores de Transcrição Kruppel-Like/genética , Pulmão/irrigação sanguínea , Pulmão/citologia , Pulmão/patologia , Masculino , Camundongos , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Cultura Primária de Células , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/patologia , Artéria Pulmonar/citologia , Artéria Pulmonar/patologia , Transdução de Sinais/genética , Remodelação Vascular/genética , Adulto Jovem
13.
Neoplasma ; 67(3): 519-527, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32122144

RESUMO

Krüppel-like factor 8 (KLF8) regulates critical gene transcription associated with different types of cancer. A novel paradigm in tumor biology suggests that the initiation and progression of osteosarcoma (OS) are driven by osteosarcoma stem cell-like cells (OSCs), but the role and underlying mechanisms of KLF8 in OSCs are poorly elucidated. In this study, an obviously increased level of KLF8 is shown in 9 out of 10 primary OS tissues and is associated with the poor progression-free interval. Significantly, KLF8 expression in CD133+ OSCs is higher than that in CD133- counterparts. By knocking down KLF8 in CD133+ OSCs, we show that si-KLF8-OSCs can hardly form compact spheres. In the meantime, infection with si-KLF8 in CD133+ OSCs results in the downregulation of OCT4 and SOX2; increased adriamycin (ADM) sensitivity; and decreased tumorigenic potential in vivo. Mechanisms study demonstrates that KLF8 directly binds the miR-429 promoter region and regulates its expression transcriptionally. Furthermore, we indicate that miR-429 directly targets SOX2 to mediate cancer stem cell-like features in CD133+ OSCs. In the clinic, miR-429 levels are negatively associated with KLF8 levels in OS, suggesting that an elevated KLF8/miR-429 ratio may have clinical value as a predictive biomarker. In conclusion, targeting the KLF8-miR-429-SOX2 signaling pathway may provide an effective therapeutic approach to suppress the initiation and progression of OS.


Assuntos
Neoplasias Ósseas/patologia , Fatores de Transcrição Kruppel-Like/genética , MicroRNAs/genética , Células-Tronco Neoplásicas/citologia , Osteossarcoma/patologia , Fatores de Transcrição SOXB1/genética , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Osteossarcoma/genética , Fenótipo , Regiões Promotoras Genéticas , Transdução de Sinais
14.
Artigo em Inglês | MEDLINE | ID: mdl-32208992

RESUMO

We showed that increased expression of complement 3 (C3) induces dedifferentiation of mesenchymal cells and epithelial mesenchymal transition, which activate the local renin-angiotensin system (RAS) that contributes to cardiovascular and renal remodeling in spontaneously hypertensive rats (SHRs). In the present study, to investigate contributions of C3 to the development of the pathogenesis of hypertension, we evaluated the formation of renin-producing cells and roles of C3 in renin generation during differentiation of primary bone marrow-mesenchymal stem cells (MSCs) from C57BL/6 mice, Wistar-Kyoto (WKY) rats, and SHRs to smooth muscle cells (SMCs) with transforming growth factor-ß1. The expression of renin transiently increased with increases in transcription factor liver X receptor α (LXRα), and expression of C3 and Krüppel-like factor 5 (KLF5) increased during differentiation of MSCs from C57BL/6 mice, WKY rats, and SHRs to SMCs. Exogenous C3a stimulated renin and LXRα expression accompanied by nuclear translocation of LXRα. C3a receptor antagonist SB290157 suppressed renin and LXRα expression, with inhibition of nuclear translocation of LXRα during the differentiation of mouse MSCs to SMCs. The expression of C3 and KLF5 was significantly higher in the differentiated cells from SHRs compared with the cells from WKY rats during differentiation. Renin-producing cells were formed during differentiation of MSCs to SMCs, and renin generation was observed in undifferentiated SMCs, in which transient expression of renin in the differentiated cells with lower differentiation stage was stronger from SHRs than that from WKY rats. Expression and nuclear localization of LXRα in the differentiated cells from SHRs were stronger than that from WKY rats. C3 was important in forming and maintaining this undifferentiated state of SMCs from MSCs to generate renin with increases in transcription factor LXRα and KLF5. Increases in C3 expression maintain the undifferentiated state of SMCs from MSCs to generate renin that activates RAS and contributes to the pathogenesis of hypertension in SHRs.


Assuntos
Complemento C3/genética , Fatores de Transcrição Kruppel-Like/genética , Receptores X do Fígado/genética , Células-Tronco Mesenquimais/metabolismo , Miócitos de Músculo Liso/metabolismo , Angiotensina II/genética , Angiotensina II/metabolismo , Animais , Células da Medula Óssea , Diferenciação Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Regulação da Expressão Gênica , Coração/fisiopatologia , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/patologia , Rim/metabolismo , Rim/patologia , Camundongos , Ratos , Ratos Endogâmicos SHR/genética , Renina/genética , Sistema Renina-Angiotensina/genética
15.
Cancer Sci ; 111(4): 1203-1217, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32012389

RESUMO

GINS complex subunit 4 (GINS4) is essential for DNA replication initiation and elongation in the G1 /S phase cell cycle in eukaryotes, however, its functional roles and molecular mechanisms remain unclear in many aspects. Our study was designed to investigate the clinical significance, biological function, and molecular mechanism of GINS4 in colorectal cancer (CRC). First, we confirmed that GINS4 expression was significantly overexpressed in CRC cells and tissues. The immunohistochemical results in tissue microarray from 106 CRC patients showed that a high level of GINS4 expression was positively correlated with advanced T stage, higher tumor TNM stage, and poor differentiation. The results from univariate and multivariate survival analysis models based on 106 CRC patients revealed that GINS4 might serve as an independent prognostic indicator for overall survival and disease-free survival of CRC patients. Moreover, downregulated GINS4 can inhibit growth and the cell cycle and accelerate cell apoptosis progression in vitro as well as inhibit tumorigenesis in vivo. Besides, our results also indicated that Krüppel-like factor 4 (KLF4) can negatively regulate GINS4 expression at the transcriptional level and the KLF/GINS4 pathway might play a vital role in the growth and prognosis of CRC.


Assuntos
Carcinogênese/genética , Proteínas Cromossômicas não Histona/genética , Neoplasias Colorretais/genética , Fatores de Transcrição Kruppel-Like/genética , Idoso , Apoptose/genética , Biomarcadores Tumorais/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Replicação do DNA/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
16.
Nat Commun ; 11(1): 997, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081850

RESUMO

Prostate development depends on balanced cell proliferation and differentiation, and acetylated KLF5 is known to alter epithelial proliferation. It remains elusive whether post-translational modifications of transcription factors can differentially determine adult stem/progenitor cell fate. Here we report that, in human and mouse prostates, Klf5 is expressed in both basal and luminal cells, with basal cells preferentially expressing acetylated Klf5. Functionally, Klf5 is indispensable for maintaining basal progenitors, their luminal differentiation, and the proliferation of their basal and luminal progenies. Acetylated Klf5 is also essential for basal progenitors' maintenance and proper luminal differentiation, as deacetylation of Klf5 causes excess basal-to-luminal differentiation; attenuates androgen-mediated organoid organization; and retards postnatal prostate development. In basal progenitor-derived luminal cells, Klf5 deacetylation increases their proliferation and attenuates their survival and regeneration following castration and subsequent androgen restoration. Mechanistically, Klf5 deacetylation activates Notch signaling. Klf5 and its acetylation thus contribute to postnatal prostate development and regeneration by controlling basal progenitor cell fate.


Assuntos
Fatores de Transcrição Kruppel-Like/metabolismo , Próstata/crescimento & desenvolvimento , Próstata/metabolismo , Acetilação , Androgênios/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Humanos , Fatores de Transcrição Kruppel-Like/deficiência , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Orquiectomia , Organoides/citologia , Organoides/metabolismo , Próstata/citologia , Regeneração , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo
17.
Gene ; 735: 144407, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32007582

RESUMO

Krüppel-like factor13 (klf13), a member of the Krüppel-like factor family, plays a vital role in cell proliferation and differentiation. When sea cucumber Apostichopus japonicus is attacted by predators, it can spit viscera in order to escape attack, and then complete the intestine regeneration process within 15 days. However, the potential role of klf13 from A. japonicus (Aj-klf13) in the intestine regeneration of sea cucumber A. japonicus still remains unknown. In present paper, the full-length cDNA of klf13 gene from A. japonicus was cloned by RACE techniques, and it was composed of 2496 bp, including a 245 bp 5' UTR, a 1396 bp 3' UTR and a 855 bp open reading frame, which encoded a polypeptide of 284 amino acids and C2H2 zinc finger domains. The expression level of Aj-klf13 showed an increasing trend in intestine regeneration process of sea cucumber, and it reached the highest at 6 days, returning to the normal at 15 days. By western blot, the expression level of Aj-KLF13 protein was basically consistent with that of Aj-klf13 gene. The expression locations of protein by immunofluorescence indicated that Aj-KLF13 was widely expressed in the normal physiological state and intestine regeneration process of sea cucumbers, which was in the nucleus. There was tissue specificity of the protein, which was mainly distributed in luminal epithelium and coelomic epithelium. These results indicate that Aj-klf13 plays a crucial role in the intestine regeneration process of sea cucumber A. japonicus.


Assuntos
Intestinos/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Regeneração , Stichopus/genética , Animais , Clonagem Molecular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Mucosa Intestinal/metabolismo , Fatores de Transcrição Kruppel-Like/química , Fatores de Transcrição Kruppel-Like/metabolismo , Stichopus/metabolismo
18.
J Surg Res ; 250: 216-223, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32092599

RESUMO

BACKGROUND: Krüppel-like factor 7 (KLF7), which belongs to the KLF family of zinc finger transcription factors, plays a critical role in regulating gene expression. It was reported that KLF7 overexpression was closely related to the progression of gastric cancer. However, the role of KLF7 in lung adenocarcinoma (LAC) has not been elucidated. The aim of our study is to investigate the expression pattern of KLF7 and explore whether the KLF7 expression is correlated with unfavorable clinical outcome of patients with LAC. MATERIALS AND METHODS: The protein and mRNA levels of KLF7 were examined in LAC tissues by using immunohistochemistry staining and quantitative reverse transcription polymerase chain reaction, respectively. The prognostic role of KLF7 in patients with LAC was assessed using univariate and multivariate analyses. Clinical outcomes were evaluated by Kaplan-Meier analysis and logrank test. The effects of KLF7 on lung cancer cells were investigated through cellular experiments. RESULTS: KLF7 expression was elevated in LAC tissues compared with adjacent normal tissues. High protein level of KLF7 was correlated with larger tumor size, positive lymph node metastasis, and advanced TNM stage. Moreover, patients with LAC with higher expression level of KLF7 had poorer overall survival, and KLF7 was identified as an unfavorable independent prognosis factor. Knockdown of KLF7 can suppress the proliferation and invasion abilities of cancer cells. CONCLUSIONS: Our studies revealed that high KLF7 expression level was significantly associated with the poorer clinical outcomes of patients with LAC, indicating the potential role of KLF7 as a novel prognostic biomarker and therapeutic target.


Assuntos
Adenocarcinoma de Pulmão/genética , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Pulmonares/genética , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/genética , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Metástase Linfática/genética , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
19.
Am J Chin Med ; 48(2): 357-372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32108493

RESUMO

The effects of thrombo-prevention, such as antiplatelet and anticoagulant activity, have been reported with the usage of Ginkgo biloba extract (GbE); however, the detailed mechanism has not yet been fully investigated, especially the role of Krüppel-like factor 2 (KLF2). This study aimed to investigate whether GbE can activate KLF2 and then induce thrombomodulin (TM) and tissue-type plasminogen activator (t-PA) secretion to enhance the effects of thrombo-prevention. Different concentrations of GbE were incubated with human umbilical vein endothelial cells (HUVECs) to evaluate its effect on endothelial cells. We found that KLF2 expression is correlated to the risk of atherosclerosis and venous thromboembolism in clinical practice. In the HUVEC cell model, GbE stimulated the expression of KLF2 in a dose-dependent manner. Moreover, TM and t-PA secretion increased when the cells were cultured with GbE. Both the expressions and activities of TM and t-PA in the GbE-treated cells declined after KLF2 was blocked by shKLF2. In sum, with GbE treatment, KLF2 expression in human endothelial cells was significantly activated, which in turn induced an increase in the protein expression and activity of TM and t-PA. After shRNA inhibited the KLF2 expression, GbE stopped inducing the expression and activity of TM and t-PA. These findings suggest that GbE exerts an antithrombotic effect on endothelial cells by increasing the TM expression and t-PA secretion; further, KLF2 is a key factor in this mechanism.


Assuntos
Células Endoteliais/metabolismo , Expressão Gênica/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Extratos Vegetais/farmacologia , Trombomodulina/genética , Trombomodulina/metabolismo , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tecidual/metabolismo , Células Cultivadas , Humanos
20.
Cell Prolif ; 53(3): e12784, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32080957

RESUMO

OBJECTIVES: CD31hi EMCNhi vessels (CD31, also known as PECAM1 [platelet and endothelial cell adhesion molecule 1]; EMCN, endomucin), which are strongly positive for CD31 and endomucin, couple angiogenesis and osteogenesis. However, the role of CD31hi EMCNhi vessels in bone regeneration remains unknown. In the present study, we investigated the role of CD31hi EMCNhi vessels in the process of bone regeneration. MATERIALS AND METHODS: We used endothelial-specific Krüppel like factor 3 (Klf3) knockout mice and ophiopogonin D treatment to interfere with CD31hi EMCNhi vessel formation. We constructed a bone regeneration model by surgical ablation of the trabecular bone. Immunofluorescence and micro-computed tomography (CT) were used to detect CD31hi EMCNhi vessels and bone formation. RESULTS: CD31hi EMCNhi vessels participate in the process of bone regeneration, such that endothelial-specific Klf3 knockout mice showed increased CD31hi EMCNhi vessels and osteoprogenitors in the bone regeneration area, and further accelerated bone formation. We also demonstrated that the natural compound, ophiopogonin D, acts as a KLF3 inhibitor to promote vessels formation both in vitro and in vivo. Administration of ophiopogonin D increased the abundance of CD31hi Emcnhi vessels and accelerated bone healing. CONCLUSIONS: Our findings confirmed the important role of CD31hi Emcnhi vessels in bone regeneration and provided a new target to treat bone fracture or promote bone regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Saponinas/farmacologia , Sialoglicoproteínas/metabolismo , Espirostanos/farmacologia , Animais , Células Cultivadas , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteogênese/efeitos dos fármacos
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