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1.
Cell Death Dis ; 11(1): 39, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959745

RESUMO

Ginsenosides exhibit a large variety of biological activities in maintaining physical health; however, the molecule underpinnings underlining these biological activities remain to be defined. Here, we took a cellular condition that compound K (CK) induces autophagic cell death in HeLa cells, and setup a high-throughput genetic screening using CRISPR technology. We have identified a number of CK-resistant and CK-sensitive genes, and further validated PMAIP1 as a CK-resistant gene and WASH1 as a CK-sensitive gene. Compound K treatment reduces the expression of WASH1, which further accelerates the autophagic cell death, highlighting WASH1 as an interesting downstream mediator of CK effects. Overall, our study offers an easy-to-adopt platform to study the functional mediators of ginsenosides, and provides a candidate list of genes that are potential targets of CK.

2.
Cell Rep ; 29(3): 781-784, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618644

RESUMO

This Matters Arising Response paper addresses the Hoch et al. (2019) Matters Arising paper published concurrently in this issue of Cell Reports. The genetic study in humans revealed a strong association of DNA variants in the SLC16A11 coding region with type 2 diabetes mellitus (T2DM). However, how these T2D variants affect the function of SLC16A11 remains controversial. In Zhao et al. (2019), with studies using genetic knockout mouse models and in vivo gene reconstitution experiments, we demonstrated gain of aberrant functions of mutant SLC16A11-carrying T2D variants, which cause liver steatosis and insulin resistance. Hoch et al. (2019) raise concerns regarding the animal models and experimental settings used in the study. Here, we address their concerns and emphasize that discoveries from the physiological studies of SLC16A11 by using mouse models disagree with the previous proposal by Rusu et al. (2017) that "therapeutics that enhance SLC16A11 levels or activity may be beneficial for T2D."

3.
World J Stem Cells ; 11(8): 535-547, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31523372

RESUMO

Human hepatocyte-like cells (HLCs) derived from human pluripotent stem cells (hPSCs) promise a valuable source of cells with human genetic background, physiologically relevant liver functions, and unlimited supply. With over 10 years' efforts in this field, great achievements have been made. HLCs have been successfully derived and applied in disease modeling, toxicity testing and drug discovery. Large cohorts of induced pluripotent stem cells-derived HLCs have been recently applied in studying population genetics and functional outputs of common genetic variants in vitro. This has offered a new paradigm for genome-wide association studies and possibly in vitro pharmacogenomics in the nearly future. However, HLCs have not yet been successfully applied in bioartificial liver devices and have only displayed limited success in cell transplantation. HLCs still have an immature hepatocyte phenotype and exist as a population with great heterogeneity, and HLCs derived from different hPSC lines display variable differentiation efficiency. Therefore, continuous improvement to the quality of HLCs, deeper investigation of relevant biological processes, and proper adaptation of recent advances in cell culture platforms, genome editing technology, and bioengineering systems are required before HLCs can fulfill the needs in basic and translational research. In this review, we summarize the discoveries, achievements, and challenges in the derivation and applications of HLCs.

4.
Oral Dis ; 25(7): 1789-1797, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31283861

RESUMO

BACKGROUND: Porphyromonas gingivalis is the main pathogen of periodontal disease affecting over half of the worldwide adult population. Recent studies have shown that P. gingivalis is related to the development of non-alcoholic fatty liver disease (NAFLD), a global major chronic liver disease, especially in developed countries. However, how P. gingivalis contributes to the pathogenesis of NAFLD has not been fully clarified. We aimed to conduct a preliminary exploration of the underlying mechanism of P. gingivalis infection in the development of NAFLD. METHODS: Human hepatocellular cells HepG2 were incubated with/without oleic acid (OA) and tested for lipid accumulation upon stimulation by lipopolysaccharide (LPS) derived from P. gingivalis or Escherichia coli. Intracellular lipid droplet formation was analyzed and quantified by Oil Red O staining. The involvement of signaling pathway molecules and pro-inflammatory cytokines related to NF-κB and MAPKs were examined with Western blot and quantitative real-time PCR (qRT-PCR) analyses and further evaluated with inhibitor treatment and RNA interference. RESULTS: HepG2 cells accumulated more intracellular lipids when stimulated with P. gingivalis LPS, as compared to cells treated with E. coli LPS or control. Further pathway analysis demonstrated that after stimulation with P. gingivalis LPS, cells displayed significantly upregulated MyD88 expression, increased phosphorylation of p65 and JNK, and more release of pro-inflammatory cytokines, such as IL-1, IL-8, and TNF-α. In addition, suppression of phosphorylation of p65 and JNK by inhibitors and RNA interference resulted in a reduction in lipid accumulation upon P. gingivalis LPS treatment. CONCLUSIONS: These results suggest that P. gingivalis-derived LPS may contribute to intracellular lipid accumulation and inflammatory reaction of HepG2 cells via the activation of NF-κB and JNK signaling pathways. This study offers a possible explanation to the functional involvement of P. gingivalis infection in the pathological progression of NAFLD. These findings may help design new treatment strategies in NAFLD.


Assuntos
Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases , NF-kappa B , Hepatopatia Gordurosa não Alcoólica/patologia , Periodontite/microbiologia , Porphyromonas gingivalis , Adulto , Infecções por Bacteroidaceae , Western Blotting , Humanos , Hepatopatia Gordurosa não Alcoólica/microbiologia , Porphyromonas gingivalis/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real
5.
Cell Rep ; 26(4): 884-892.e4, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30673611

RESUMO

DNA variants in the SLC16A11 coding region were identified to be strongly associated with type 2 diabetes (T2DM) in a Mexican population. Previous studies suggested that these variants disrupt SLC16A11 function and therefore proposed to revive SLC16A11 levels or activity to achieve therapeutic benefit. However, with knockout mouse models, here we show that Slc16a11 depletion has no significant metabolic defects. Further studies demonstrate that reconstitution of the mutant, but not the wild-type Slc16a11, in the liver of knockout mice causes more triglyceride accumulation and induction of insulin resistance via upregulation of lipin 1, suggesting gaining of aberrant functions of the mutant protein that affects lipid metabolism. Our findings offer a different explanation to the function of these diabetic variants, challenging the concept of enhancing SLC16A11 function to treat T2DM. The contradictory results by our and previous studies suggest that how the SLC16A11 locus contributes to human metabolism warrants further investigation.

6.
Mol Cancer Res ; 17(2): 655-665, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30401720

RESUMO

The E-cadherin/ß-catenin signaling pathway plays a critical role in the maintenance of epithelial architecture and regulation of tumor progression. Normally, E-cadherin locates on the cell surface with its cytosolic domain linking to the actin cytoskeleton through interaction with catenins. Although the nuclear localization of E-cadherin has been frequently observed in various types of cancers, little is known regarding the functional consequences of its nuclear translocation. Here, we showed that in colorectal cancer samples and cell lines, E-cadherin localized in the nucleus; and the nuclear localization was mediated through protein interaction with CTNND1. In the nucleus, E-cadherin was acetylated by CREB-binding protein at Lysine870 and Lysine871 in its ß-catenin-binding domain, and the acetylation can be reversed by SIRT2. Acetylation of nuclear E-cadherin attenuated its interaction with ß-catenin, which therefore released ß-catenin from the complex, resulting in increased expression of its downstream genes and accelerated tumor growth and migration. Further study showed that acetylation level of nuclear E-cadherin had high prognostic significance in clinical colorectal samples. Taken together, our findings reveal a novel mechanism of tumor progression through posttranslational modification of E-cadherin, which may serve as a potential drug target of tumor therapy. IMPLICATIONS: This finding that acetylation of nuclear E-cadherin regulates ß-catenin activity expands our understanding of the acetylation of E-cadherin promotes colorectal cancer cell growth and suggests novel therapeutic approaches of targeting acetylation in tumors.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Neoplasias Colorretais/metabolismo , beta Catenina/metabolismo , Acetilação , Carcinogênese , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Neoplasias Colorretais/patologia , Células HCT116 , Células HEK293 , Humanos
7.
EBioMedicine ; 37: 344-355, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30348622

RESUMO

BACKGROUND: The pharmacological activation of thermogenesis in brown adipose tissue has long been considered promising strategies to treat obesity. However, identification of safe and effective agents remains a challenge. In this study, we addressed this challenge by developing a cellular system with a fluorescence readout, and applied in a high-throughput manner to screen for FDA-approved drugs that may activate endogenous UCP1 expression in adipocytes. METHODS: We have generated a Ucp1-2A-GFP reporter mouse, in which GFP intensity serves as a surrogate of the endogenous expression level of UCP1 protein; and immortalized brown adipocytes were derived from this mouse model and applied in drug screening. Candidate drugs were further tested in mouse models either fed with normal chow or high fat diet to induce obesity. FINDINGS: By using the cellular screening platform, we identified a group of FDA-approved drugs that can upregulate UCP1 expression in brown adipocyte, including previously known UCP1 activators and new candidate drugs. Further studies focusing on a previously unreported drug-sutent, revealed that sutent treatment could increase the energy expenditure and inhibit lipid synthesis in mouse adipose and liver tissues, resulting in improved metabolism and resistance to obesity. INTERPRETATION: This study offered an easy-to-use cellular screening system for UCP1 activators, and provided a candidate list of FDA-approved drugs that can potentially treat obesity. Further study of these candidates may shed new light on the drug discovery towards obesity. FUND: National Key Research and Development Program and the Strategic Priority Research Program of the Chinese Academy of Sciences, etc. (250 words).


Assuntos
Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Desacopladora 1/biossíntese , Adipócitos Marrons/patologia , Tecido Adiposo Marrom/patologia , Animais , Linhagem Celular Transformada , Aprovação de Drogas , Avaliação Pré-Clínica de Medicamentos , Camundongos , Camundongos Transgênicos , Proteína Desacopladora 1/genética , Estados Unidos , United States Food and Drug Administration
8.
Stem Cell Reports ; 11(1): 22-31, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29861165

RESUMO

Hepatocyte-like cells (HLCs) derived from human pluripotent stem cells (hPSCs) offer a promising cell resource for disease modeling and transplantation. However, differentiated HLCs exhibit an immature phenotype and comprise a heterogeneous population. Thus, a better understanding of HLC differentiation will improve the likelihood of future application. Here, by taking advantage of CRISPR-Cas9-based genome-wide screening technology and a high-throughput hPSC screening platform with a reporter readout, we identified several potential genetic regulators of HLC differentiation. By using a chemical screening approach within our platform, we also identified compounds that can further promote HLC differentiation and preserve the characteristics of in vitro cultured primary hepatocytes. Remarkably, both screenings identified histone deacetylase 3 (HDAC3) as a key regulator in hepatic differentiation. Mechanistically, HDAC3 formed a complex with liver transcriptional factors, e.g., HNF4, and co-regulated the transcriptional program during hepatic differentiation. This study highlights a broadly useful approach for studying and optimizing hPSC differentiation.


Assuntos
Diferenciação Celular , Hepatócitos/citologia , Hepatócitos/metabolismo , Histona Desacetilases/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Sistemas CRISPR-Cas , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Células Cultivadas , Citometria de Fluxo , Edição de Genes , Regulação da Expressão Gênica no Desenvolvimento , Marcação de Genes , Genes Reporter , Genes abl , Fator 4 Nuclear de Hepatócito/metabolismo , Histona Desacetilases/genética , Humanos , Modelos Biológicos , Fenilenodiaminas/farmacologia
9.
Nat Commun ; 8(1): 1259, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29097654

RESUMO

Lysine acetylation is a post-translational modification known to regulate protein functions. Here we identify several acetylation sites of the influenza A virus nucleoprotein (NP), including the lysine residues K77, K113 and K229. Viral growth of mutant virus encoding K229R, mimicking a non-acetylated NP lysine residue, is severely impaired compared to wildtype or the mutant viruses encoding K77R or K113R. This attenuation is not the result of decreased polymerase activity, altered protein expression or disordered vRNP co-segregation but rather caused by impaired particle release. Interestingly, release deficiency is also observed mimicking constant acetylation at this site (K229Q), whereas virus encoding NP-K113Q could not be generated. However, mimicking NP hyper-acetylation at K77 and K229 severely diminishes viral polymerase activity, while mimicking NP hypo-acetylation at these sites has no effect on viral replication. These results suggest that NP acetylation at K77, K113 and K229 impacts multiple steps in viral replication of influenza A viruses.


Assuntos
Vírus da Influenza A/genética , Lisina/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas do Core Viral/genética , Replicação Viral/genética , Acetilação , Animais , Cães , Células HEK293 , Humanos , Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza A/metabolismo , Células Madin Darby de Rim Canino , Mutação , Proteínas de Ligação a RNA/metabolismo , Proteínas do Core Viral/metabolismo
10.
Cell Physiol Biochem ; 43(6): 2525-2534, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29130970

RESUMO

BACKGROUND/AIMS: The mammalian skull vault is a highly regulated structure and consists of several membrane bones of different tissue origins (e.g. neural crest derived frontal bone and mesoderm derived parietal bone). Although membrane bones form through intramembranous ossification, neural crest derived frontal bone has superior osteoblast activity and bone regeneration ability, triggering a novel conception for craniofacial reconstruction and bone regeneration called endogenous calvarial regeneration. However, a comprehensive landscape of the genes and signaling pathways involved in this process is not clear. METHODS: Transcriptome analysis within the two bone elements is firstly performed to determine the physiological signatures of differential gene expressions in mouse skull vault. RESULTS: Frontal bone tissues and parietal bone tissues maintain tissue origin through special gene expression similar to neural crest vs mesoderm tissue, and physiological functions between these two tissues are also found in differences related to proliferation, differentiation and extracellular matrix production and clustered signaling pathways. CONCLUSION: Our data provide novel insights into the potential gene regulatory network in regulating the development of neural crest-derived frontal bone and mesoderm-derived parietal bone.


Assuntos
Osso Parietal/metabolismo , Animais , Diferenciação Celular , Embrião de Mamíferos/metabolismo , Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Crista Neural/metabolismo , RNA/isolamento & purificação , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Transdução de Sinais
11.
Oncotarget ; 8(41): 70142-70155, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-29050267

RESUMO

The small ubiquitin-related modifier (SUMO) system is essential for smooth progression of cell cycle at the G2/M phase. Many centromeric proteins are reversibly SUMOylated to ensure proper chromosome segregation at the mitosis. SUMOylation of centromeric Origin Recognition Complex subunit 2 (ORC2) at the G2/M phase is essential in maintaining genome integrity. However, how ORC2 SUMOylation is regulated remains largely unclear. Here we show that ORC2 SUMOylation is reversibly controlled by SUMO E3 ligase PIAS4 and De-SUMOylase SENP2. Either depletion of PIAS4 or overexpression of SENP2 eliminated SUMOylation of ORC2 at the G/M phase and consequently resulted in abnormal centromeric histone H3 lysine 4 methylation. Cells stably expressing SENP2 protein or small interfering RNA for PIAS4 bypassed mitosis and endoreduplicated their genome to become polyploidy. Furthermore, percentage of polyploid cells is reduced after coexpression of ORC2-SUMO2 fusion protein. Thus, the proper regulation of ORC2 SUMOylation at the G2/M phase by PIAS4 and SENP2 is critical for smooth progression of the mitotic cycle of cells.

12.
Cell Death Dis ; 7(12): e2508, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27906182

RESUMO

Transforming growth factor beta (TGFß) signaling in breast cancer is selectively associated with pulmonary metastasis. However, the underlying mechanisms remain unclear. Here we show that Bcl-3, a member of the IκB family, serves as a critical regulator in TGFß signaling to modulate breast cancer pulmonary metastasis. Bcl-3 expression was significantly associated with metastasis-free survival in breast cancer patients. Bcl-3 deletion inhibited the migration and invasion of breast cancer cells in vitro, as well as breast cancer lung metastasis in vivo. Bcl-3 was required for the expression of downstream TGFß signaling genes that are involved in breast cancer lung metastasis. Bcl-3 knockdown enhanced the degradation of Smad3 but not Smad2 following TGFß treatment. Bcl-3 could bind to Smad3 and prevent the ubiquitination and degradation of Smad3 protein. These results indicate that Bcl-3 serves as a promising target to prevent breast tumor lung metastasis.


Assuntos
Neoplasias da Mama/patologia , Neoplasias Pulmonares/secundário , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Proteína Smad3/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Estabilidade Proteica , Transdução de Sinais/genética
13.
Cell Death Dis ; 7(10): e2402, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27711077

RESUMO

Dysfunction of nuclear factor-κB (NF-κB) signaling has been causally associated with numerous human malignancies. Although the NF-κB family of genes has been implicated in endometrial carcinogenesis, information regarding the involvement of central regulators of NF-κB signaling in human endometrial cancer (EC) is limited. Here, we investigated the specific roles of canonical and noncanonical NF-κB signaling in endometrial tumorigenesis. We found that NF-κB RelB protein, but not RelA, displayed high expression in EC samples and cell lines, with predominant elevation in endometrioid adenocarcinoma (EEC). Moreover, tumor cell-intrinsic RelB was responsible for the abundant levels of c-Myc, cyclin D1, Bcl-2 and Bcl-xL, which are key regulators of cell cycle transition, apoptosis and proliferation in EEC. In contrast, p27 expression was enhanced by RelB depletion. Thus, increased RelB in human EC is associated with enhanced EEC cell growth, leading to endometrial cell tumorigenicity. Our results reveal that regulatory RelB in noncanonical NF-κB signaling may serve as a therapeutic target to block EC initiation.


Assuntos
Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma Endometrioide/metabolismo , Carcinoma Endometrioide/patologia , Ciclo Celular , NF-kappa B/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelB/metabolismo , Animais , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Fase G1/genética , Humanos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Fase S/genética , Transdução de Sinais/genética
14.
Cancer Res ; 75(9): 1801-14, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25744720

RESUMO

GPRC5A is a G-protein-coupled receptor expressed in lung tissue but repressed in most human lung cancers. Studies in Gprc5a(-/-) mice have established its role as a tumor-suppressor function in this setting, but the basis for its role has been obscure. Here, we report that GPRC5A functions as a negative modulator of EGFR signaling. Mouse tracheal epithelial cells (MTEC) from Gprc5a(-/-) mice exhibited a relative increase in EGFR and downstream STAT3 signaling, whereas GPRC5A expression inhibited EGFR and STAT3 signaling. GPRC5A physically interacted with EGFR through its transmembrane domain, which was required for its EGFR inhibitory activity. Gprc5a(-/-) MTEC were much more susceptible to EGFR inhibitors than wild-type MTEC, suggesting their dependence on EGFR signaling for proliferation and survival. Dysregulated EGFR and STAT3 were identified in the normal epithelia of small and terminal bronchioles as well as tumors of Gprc5a(-/-) mouse lungs. Moreover, in these lungs EGFR inhibitor treatment inhibited EGFR and STAT3 activation along with cell proliferation. Finally, overexpression of ectopic GPRC5A in human non-small cell lung carcinoma cells inhibited both EGF-induced and constitutively activated EGFR signaling. Taken together, our results show how GPRC5A deficiency leads to dysregulated EGFR and STAT3 signaling and lung tumorigenesis. Cancer Res; 75(9); 1801-14. ©2015 AACR.


Assuntos
Receptores ErbB/metabolismo , Neoplasias Pulmonares/genética , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Bronquíolos/metabolismo , Carcinogênese/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Células Epiteliais/metabolismo , Receptores ErbB/genética , Células HEK293 , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores Acoplados a Proteínas-G/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
15.
PLoS Pathog ; 9(8): e1003545, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23990780

RESUMO

Nuclear hormone receptors respond to small molecules such as retinoids or steroids and regulate development. Signaling in the conserved p38/PMK-1 MAP kinase pathway regulates innate immunity. In this study, we show that the Caenorhabditis elegans nuclear receptor DAF-12 negatively regulates the defense against pathogens via the downstream let-7 family of microRNAs, which directly target SKN-1, a gene downstream of PMK-1. These findings identify nuclear hormone receptors as components of innate immunity that crosstalk with the p38/PMK-1 MAP kinase pathway.


Assuntos
Proteínas de Caenorhabditis elegans/imunologia , Caenorhabditis elegans/imunologia , Imunidade Inata/fisiologia , Sistema de Sinalização das MAP Quinases/imunologia , MicroRNAs/imunologia , Receptores Citoplasmáticos e Nucleares/imunologia , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Sistema de Sinalização das MAP Quinases/genética , MicroRNAs/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/imunologia , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia
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