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1.
Jpn J Clin Oncol ; 45(8): 738-44, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25917358

RESUMO

OBJECTIVE: Previous studies have shown that the micro-ribonucleic acid miR-501-5p is upregulated in hepatocellular carcinoma cells and tissues with high hepatitis B virus replication, and that miR-501 overexpression significantly promotes hepatitis B virus replication. We further analysed a published microarray-based high-throughput dataset (NCBI/GEO/GSE36915) and found that miR-501-5p was upregulated in hepatocellular carcinoma tumour tissues. We therefore investigated the possible function of miR-501-5p during the development of hepatocellular carcinoma. METHODS: Expression of miR-501-5p in human hepatocellular carcinoma specimens and cell lines was assessed, using real-time polymerase chain reaction. Luciferase reporter assays were used to confirm CYLD as a target of miR-501-5p. The effect of miR-501-5p on cell proliferation was confirmed, using tetrazolium and colony formation assays. Gene and protein expression were examined, using real-time polymerase chain reaction and western blotting, respectively. RESULTS: MiR-501-5p was upregulated in hepatocellular carcinoma specimens and cell lines, and directly targeted the 3' untranslated region of CYLD. MiR-501-5p upregulation corresponded with a downregulation of CYLD in the same tissues and cell lines, and overexpression of MiR-501-5p decreased CYLD expression, increased expression of cyclin D1 and c-myc and promoted the proliferation of hepatocellular carcinoma cells in vitro. CONCLUSIONS: This study suggests that miR-501-5p may play an important role in the development of hepatocellular carcinoma by promoting cell proliferation, and indicates that miR-501-5p may represent a novel therapeutic target for hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Western Blotting , Proliferação de Células , Enzima Desubiquitinante CYLD , Regulação Neoplásica da Expressão Gênica , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
2.
J Ethnopharmacol ; 325: 117739, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38301986

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Licorice is the dry roots and rhizomes of Glycyrrhiza uralensis Fisch., Glycyrrhiza glabra L. and Glycyrrhiza inflata Bat., which was first recorded in Shengnong's herbal classic. Licorice flavonoid (LF) is the main compound isolated from licorice with an indispensable action in treating gastric ulcer (GU). However, the underlying mechanisms need to be further explored. AIM OF THE STUDY: This study aimed to investigate and further elucidate the mechanisms of LF against ethanol-induced GU using an integrated approach. MATERIALS AND METHODS: The anti-GU effects of LF were evaluated in an ethanol-induced gastric injury rat model. Then, the metabolomics approach was applied to explore the specific metabolites and metabolic pathways. Next, the network pharmacology combined with metabolomics strategy was employed to predict the targets and pathways of LF for GU. Finally, these predictions were validated by molecular docking, RT-qPCR, and western blotting. RESULTS: LF had a positive impact on gastric injury and regulated the expression of GU-related factors. Upon serum metabolomics analysis, 25 metabolic biomarkers of LF in GU treatment were identified, which were primarily involved in amino acid metabolism, carbohydrate metabolism, and other related processes. Subsequently, a "components-targets-metabolites" network was constructed, revealing six key targets (HSP90AA1, AKT1, MAPK1, EGFR, ESR1, PIK3CA) that may be associated with GU treatment. More importantly, KEGG analysis highlighted the importance of the PI3K/AKT pathway including key targets, as a critical route through which LF exerted its anti-GU effects. Molecular docking analyses confirmed that the core components of LF exhibited a strong affinity for key targets. Furthermore, RT-qPCR and western blotting results indicated that LF could reverse the expression of these targets, activate the PI3K/AKT pathway, and ultimately reduce apoptosis. CONCLUSION: LF exerted a gastroprotective effect against gastric ulcer induced by ethanol, and the therapeutic mechanism may involve improving metabolism and suppressing apoptosis through the PI3K-AKT pathway.


Assuntos
Glycyrrhiza , Úlcera Gástrica , Animais , Ratos , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Simulação de Acoplamento Molecular , Apoptose , Etanol , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Transdução de Sinais
3.
Cell Prolif ; : e13683, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830795

RESUMO

Chimeric antigen receptor-natural killer (CAR-NK) cell therapy is emerging as a promising cancer treatment, with notable safety and source diversity benefits over CAR-T cells. This study focused on optimizing CAR constructs for NK cells to maximize their therapeutic potential. We designed seven CD19 CAR constructs and expressed them in NK cells using a retroviral system, assessing their tumour-killing efficacy and persistence. Results showed all constructs enhanced tumour-killing and prolonged survival in tumour-bearing mice. In particular, CAR1 (CD8 TMD-CD3ζ SD)-NK cells showed superior efficacy in treating tumour-bearing animals and exhibited enhanced persistence when combined with OX40 co-stimulatory domain. Of note, CAR1-NK cells were most effective at lower effector-to-target ratios, while CAR4 (CD8 TMD-OX40 CD- FcεRIγ SD) compromised NK cell expansion ability. Superior survival rates were noted in mice treated with CAR1-, CAR2 (CD8 TMD- FcεRIγ SD)-, CAR3 (CD8 TMD-OX40 CD- CD3ζ SD)- and CAR4-NK cells over those treated with CAR5 (CD28 TMD- FcεRIγ SD)-, CAR6 (CD8 TMD-4-1BB CD-CD3ζ 1-ITAM SD)- and CAR7 (CD8 TMD-OX40 CD-CD3ζ 1-ITAM SD)-NK cells, with CAR5-NK cells showing the weakest anti-tumour activity. Increased expression of exhaustion markers, especially in CAR7-NK cells, suggests that combining CAR-NK cells with immune checkpoint inhibitors might improve anti-tumour outcomes. These findings provide crucial insights for developing CAR-NK cell products for clinical applications.

4.
Cell Prolif ; : e13727, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136096

RESUMO

CAR-NK cell therapy does not require HLA matching and has minimal side effects. However, traditional methods of engineering CARs into human tissue-derived NK cells exhibit heterogeneity, low transduction efficiency, and high manufacturing costs. Here, we provide a reliable approach for generating large-scale and cryopreserved mesothelin (MSLN) CAR-NK cells from human embryonic stem cells (hESCs) as an alternative cell source. We first constructed MSLN CAR-expressing hESCs to reduce CAR engineering costs and subsequently differentiated these stem cells into MSLN CAR-NK cells via an efficient organoid induction system. The MSLN CAR-NK cells exhibit the typical expression patterns of activating receptors, inhibitory receptors, and effector molecules of NK cells. In the presence of tumour cells, the MSLN CAR-NK cells show increased secretion of IFN-γ and TNF-α, as well as elevated CD107a expression level compared with induced NK cells. We cryopreserved the MSLN CAR-NK cells in liquid nitrogen using a clinical-grade freezing medium (CS10) for more than 6 months to mimic an off-the-shelf CAR-NK cell product. The thawed MSLN CAR-NK cells immediately recovered after 48-72-h culture and effectively eliminated ovarian tumour cells, including human primary ovarian tumour cells from patients. The thawed MSLN CAR-NK cells efficiently suppressed ovarian tumour development in vivo and prolonged the survival of tumour-bearing mice. Our study provides insights into the clinical translation of hESC-derived MSLN CAR-NK cells as a promising off-the-shelf cell product.

5.
Cell Prolif ; 57(5): e13588, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38124457

RESUMO

'Requirements for Human Natural Killer Cells' is the latest set of guidelines on human NK cells in China, jointly drafted and agreed upon by experts from the Standards Committee of Chinese Society for Cell Biology. This standard specifies requirements for the human natural killer (NK) cells, including the technical requirements, test methods, test regulations, instructions for use, labeling requirements, packaging requirements, storage and transportation requirements, and waste disposal requirements of NK cells. This standard is applicable for the quality control of NK cells, derived from human tissues, or differentiated/transdifferentiated from stem cells. It was originally released by the Chinese Society for Cell Biology on 30 August, 2022. We hope that the publication of these guidelines will promote institutional establishment, acceptance, and execution of proper protocols and accelerate the international standardization of human NK cells for applications.


Assuntos
Células Matadoras Naturais , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/citologia , Humanos , China , Controle de Qualidade
6.
Biomed Pharmacother ; 169: 115868, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37952360

RESUMO

Licorice flavonoid (LF) is the main component of Glycyrrhizae Radix et Rhizoma, a "medicine food homology" herbal medicine, which has anti-digestive ulcer activity, but the mechanism in anti-gastric ulcer (GU) remains to be elucidated. In this study, we manifested that LF increased the viability of human gastric mucosal epithelial (GES-1) cells, attenuated ethanol (EtOH)-induced manifestations, reduced histological injury, suppressed inflammation, and restored gastric mucosal barrier in GU rats. After LF therapy, the EtOH-induced gut dysbiosis was partly modulated, and short-chain fatty acids (SCFAs) like butyric acid, propionic acid, and valeric acid were found in higher concentrations. We discovered that the majority of genera that increased in the GU group had a negative correlation with SCFAs in the intestinal tract. In addition, LF-upregulated SCFAs boosted mucus secretion in the gastric epithelium and the expression of mucoprotein (MUC) 5AC and MUC6, particularly the MUC5AC in the gastric foveola. Moreover, LF triggered the EGFR/ERK signal pathway which promoted gastric mucus cell regeneration. Therefore, the findings indicated that LF could inhibit inflammation, promote mucosal barrier repair and angiogenesis, regulate gut microbiota and SCFA metabolism; more importantly, promote epithelial proliferation via activation of the EGFR/ERK pathway, exerting a protective and regenerative effect on the gastric mucosa.


Assuntos
Microbioma Gastrointestinal , Glycyrrhiza , Úlcera Gástrica , Ratos , Humanos , Animais , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/metabolismo , Ácidos Graxos Voláteis/metabolismo , Inflamação/metabolismo , Etanol/efeitos adversos , Muco/metabolismo , Receptores ErbB/metabolismo
7.
Cell Prolif ; 55(6): e13235, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35582777

RESUMO

OBJECTIVES: The expression of transcription factor Hoxb5 specifically marks the functional haematopoietic stem cells (HSC) in mice. However, our recent work demonstrated that ectopic expression of Hoxb5 exerted little effect on HSC but could convert B-cell progenitors into functional T cells in vivo. Thus, cell type- and development stage-specific roles of Hoxb5 in haematopoietic hierarchy await more extensive exploration. In this study, we aim to investigate the effect of Hoxb5 expression in multipotent blood progenitor cells. MATERIALS AND METHODS: A Mx1cre/RosaLSL-Hoxb5-EGFP/+ mouse model was used to evaluate the effect of Hoxb5 expression in blood multipotent progenitor cells (MPP). Golden standard serial transplantation experiments were used to test the long-term haematopoiesis potential of Hoxb5-expressing MPP. Single-cell RNA-seq analysis was used to characterize the gained molecular features of Hoxb5-expressing MPP and to compare with the global transcriptome features of natural adult HSC and fetal liver HSC (FL HSC). RESULTS: Here, with a mouse strain engineered with conditional expression of Hoxb5, we unveiled that induced expression of Hoxb5 in MPP led to the generation of a de novo Sca1+ c-kit+ CD11b+ CD48+ (CD11b+ CD48+ SK) cell type, which can repopulate long-term multilineage haematopoiesis in serial transplantations. RNA-seq analysis showed that CD11b+ CD48+ SK cells exhibited acquired features of DNA replication and cell division. CONCLUSIONS: Our current study uncovers that Hoxb5 can empower MPP with self-renewal ability and indicates an alternative approach for generating HSC-like cells in vivo from blood lineage cells.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas , Proteínas de Homeodomínio/metabolismo , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Multipotentes
8.
Transplant Proc ; 54(1): 158-160, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34961599

RESUMO

Severe neurologic complications after chronic liver disease greatly affect the patient's quality of life. Hepatic myelopathy (HM) is a rare but devastating disease, in chronic liver disease. The limbs of patients with HM show slowly progressive symmetrical spastic paralysis without sensory loss. Management of this severe neurologic complication is challenging. These patients often require timely and effective clinical intervention. Although liver transplantation is one of the effective treatments for HM, the prognosis of these patients remains poor, many of them spend their lives in wheelchairs. Here, we report a patient with HM after hepatitis B virus related decompensated liver cirrhosis who recovered well after liver transplant. This work was carried out in compliance with the Helsinki Congress and the Declaration of Istanbul.


Assuntos
Hepatite B , Transplante de Fígado , Doenças da Medula Espinal , Hepatite B/complicações , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Qualidade de Vida , Doenças da Medula Espinal/etiologia , Doenças da Medula Espinal/cirurgia
9.
Transplant Proc ; 54(7): 1865-1873, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35934535

RESUMO

Liver transplantation from donors after circulatory death (DCD) is associated with considerable rates of primary nonfunction and ischemic-type biliary lesions. Compared with donation was after brain death (DBD), the biggest disadvantage of DCD is warm ischemia injury in the procurement stage. Donation after brain death followed by circulatory death (DBCD) is a unique practice in China. Such donors should donate according to the DCD procedure, that is, remove life support and donate after cardiac arrest. We retrospectively analyzed donor and recipient characteristics with preoperative and postoperative parameters according to 3 donation types to comprehensively describe incidence of ischemia reperfusion injury (IRI) related biliary complications among different donor type adult liver transplantation recipients. A total of 50 patients were included in this study (DBD group n = 17, DCD group n = 26, DBCD group n = 7). Only 1 patient, whose donor type was DBCD was diagnosed with ischemic-type biliary lesions demonstrated cast and retrograde ascending cholangitis. Rates of primary graft non-function (DBD n = 1, 5.9%; DCD n = 2, 7.7%; DBCD, 0%; P = .546) were similar and total biliary complications (DBD n = 1, 5.9%; DCD n = 1, 3.8%; DBCD N = 2, 28.6%; P = .042) were different. No differences were found regarding development of postreperfusion syndrome or coagulopathy in 3 groups. Compared with standard DBD donor, the clinical outcome of DCD donor liver transplantation was satisfactory, with no increase in the incidence of IRI, and, no difference in the incidence of ischemic bile duct complications. This work was carried out in compliance with the Helsinki Congress and the Declaration of Istanbul.


Assuntos
Transplante de Fígado , Traumatismo por Reperfusão , Obtenção de Tecidos e Órgãos , Adulto , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Morte Encefálica , Estudos Retrospectivos , Incidência , Sobrevivência de Enxerto , Doadores Vivos , Doadores de Tecidos , Traumatismo por Reperfusão/epidemiologia , Traumatismo por Reperfusão/etiologia , Morte
10.
Cell Discov ; 8(1): 121, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36344493

RESUMO

Human pluripotent stem cell (hPSC)-induced NK (iNK) cells are a source of off-the-shelf cell products for universal immune therapy. Conventional methods for iNK cell regeneration from hPSCs include embryoid body (EB) formation and feeder-based expansion steps, which are time-consuming and cause instability and high costs of manufacturing. Here, we develop an EB-free, organoid aggregate method for NK cell regeneration from hPSCs. In a short time-window of 27-day induction, millions of hPSC input can output over billions of iNK cells without the necessity of NK cell expansion feeders. The iNK cells highly express classical toxic granule proteins, apoptosis-inducing ligands, as well as abundant activating and inhibitory receptors. Functionally, the iNK cells eradicate human tumor cells via mechanisms of direct cytotoxicity, apoptosis, and antibody-dependent cellular cytotoxicity. This study provides a reliable scale-up method for regenerating human NK cells from hPSCs, which promotes the universal availability of NK cell products for immune therapy.

11.
Transplant Proc ; 53(4): 1295-1299, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33888345

RESUMO

BACKGROUND: Hepatic artery thrombosis (HAT), a serious complication after orthotopic liver transplantation, almost always leads to morbidity and mortality without urgent revascularization or retransplantation, especially if HAT occurs within a few days after transplantation. CASE PRESENTATION: Herein we describe a case report of an orthotopic liver transplantation patient surviving without hepatic artery flow due to HAT on postoperative day 1. Reanastomosis, thrombectomy, and intra-arterial thrombolysis were performed, but only retrograde arterial flow by Doppler ultrasound, not by angiography, could be demonstrated in the hepatic artery. This case report is in compliance with the Declaration of Helsinki and the Declaration of Istanbul. CONCLUSION: Based on the evidence from this patient, we believe that patients with failed revascularization can experience a long-term survival with conservative treatment. Retransplantation should be evaluated based on laboratory findings because graft function in individual patients can recover.


Assuntos
Artéria Hepática/fisiologia , Transplante de Fígado , Trombose/cirurgia , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Fibrinolíticos/uso terapêutico , Artéria Hepática/cirurgia , Humanos , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Ablação por Radiofrequência , Trombectomia , Trombose/diagnóstico , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler
12.
Transplant Proc ; 53(8): 2588-2593, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34253380

RESUMO

Invasive fungal infections, of which the most common are candidiasis and aspergillosis, are among the most important and fatal complications in solid organ transplantation. They continue to be a significant cause of morbidity and mortality in patients with involvement of the central nervous system (CNS) because of the poor CNS penetration of antifungal medications. Voriconazole yields fungicidal drug concentrations in the CNS, but its use is limited in solid organ transplant patients because of its metabolic interactions with immunosuppression. Here we report a case of invasive fungal infection in the CNS after an emergency liver transplantation due to hepatitis B virus-related acute liver failure. The patient was managed successfully with a long-term conservative medical treatment.


Assuntos
Aspergilose , Candidíase , Transplante de Fígado , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Humanos , Transplante de Fígado/efeitos adversos , Voriconazol
13.
Transplant Proc ; 52(9): 2813-2816, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32900476

RESUMO

Acute-on-chronic liver failure (ACLF) is a clinical manifestation of acute liver failure and decompensation on the basis of chronic liver disease. To date, hepatitis B virus-related ACLF is still the main cause of liver failure in China. Liver transplantation is currently the most likely treatment option to cure ACLF, but the shortage of donor livers is a barrier to its widespread use. The shortage of organs has led to increased use of expanded-criteria donors (ECDs), that is, donation after cardiac death (DCD) and its variant donation after brain and cardiac death (DBCD-China, DCBD-Switzerland). Here we report a case of liver transplantation, whose recipient was diagnosed with ACLF as a result of use of traditional Chinese medicine while the donor liver was retrieved from a renal transplant patient 4 years after transplantation. This transplant was carried out in accordance with the Helsinki Congress and the Declaration of Istanbul.


Assuntos
Insuficiência Hepática Crônica Agudizada/cirurgia , Transplante de Fígado/métodos , Medicina Tradicional Chinesa/efeitos adversos , Doadores de Tecidos/provisão & distribuição , Insuficiência Hepática Crônica Agudizada/induzido quimicamente , Morte , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Rim , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
J Immunother Cancer ; 8(2)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669292

RESUMO

Tumor-associated antigen (TAA) T-cell receptor (TCR) gene-engineered T cells exhibit great potential in antitumor immunotherapy. Considering the high costs and low availability of patient-derived peripheral blood T cells, substantial efforts have been made to explore alternatives to natural T cells. We previously reported that enforced expression of Hoxb5 converted B cells into induced T (iT) cells in vivo Here, we successfully regenerated naive OT1 (major histocompatibility complex I restricted ovalbumin antigen) iT cells (OT1-iT) in vivo by expressing Hoxb5 in pro-pre-B cells in the OT1 transgenic mouse. The OT1-iT cells can be activated and expanded in vitro in the presence of tumor cells. Particularly, these regenerated OT1-iT cells effectively eradicated tumor cells expressing the TAA (ovalbumin) both in vitro and in vivo This study provides insights into the translational applications of blood lineage-transdifferentiated T cells in immunotherapy.


Assuntos
Antígenos de Neoplasias/metabolismo , Imunoterapia/métodos , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Humanos , Camundongos
15.
Zhongguo Zhong Yao Za Zhi ; 33(19): 2188-92, 2008 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19166003

RESUMO

OBJECTIVE: To prepare colon-targetting tablets of total alkaloids of Sophora alopecuroides and evaluate the effect of pectins of different degree of esterification (DE) on sophoridine release profiles in-vitro. METHOD: Wet granulation technique was employed to prepare petin-based matrix tablets, then tablets were coated the optimal formulation with Kollicoat MAE 30 DP based on the optimal formulation and analysed their release. RESULT: Coated formulation E could target total alkaloids of S. alopecuroides to colon and various DE of pectin exerted different effects on sophoridine release. The release of low DE pectin-based matrix tablets coating with Kollicoat MAE 30 DP approximatedly fitted zere-order eqution, which was erosion depended. CONCLUSION: Low DE pectin-based matrix tablet coating with Kollicoat MAE 30 DP can deliver sophoridine to colon, hence improve the effectiveness of sophoridine.


Assuntos
Alcaloides/química , Pectinas/química , Quinolizinas/química , Sophora/química , Comprimidos/química , Animais , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Colo/química , Esterificação , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley , Matrinas
17.
Nat Cell Biol ; 20(10): 1227, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29907862

RESUMO

In the version of this Article originally published, in Fig. 2c, the '+' sign and 'OSKM' were superimposed in the label '+OSKM'. In Fig. 4e, in the labels, all instances of 'Ant' should have been 'Anti-'. And, in Fig. 7a, the label '0.0' was misplaced; it should have been on the colour scale bar. These figures have now been corrected in the online versions.

18.
Nat Cell Biol ; 20(4): 400-412, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29531310

RESUMO

Somatic cell reprogramming by exogenous factors requires cooperation with transcriptional co-activators and co-repressors to effectively remodel the epigenetic environment. How this interplay is regulated remains poorly understood. Here, we demonstrate that NCoR/SMRT co-repressors bind to pluripotency loci to create a barrier to reprogramming with the four Yamanaka factors (OCT4, SOX2, KLF4 and c-MYC), and consequently, suppressing NCoR/SMRT significantly enhances reprogramming efficiency and kinetics. The core epigenetic subunit of the NCoR/SMRT complex, histone deacetylase 3 (HDAC3), contributes to the effects of NCoR/SMRT by inducing histone deacetylation at pluripotency loci. Among the Yamanaka factors, recruitment of NCoR/SMRT-HDAC3 to genomic loci is mostly facilitated by c-MYC. Hence, we describe how c-MYC is beneficial for the early phase of reprogramming but deleterious later. Overall, we uncover a role for NCoR/SMRT co-repressors in reprogramming and propose a dual function for c-MYC in this process.


Assuntos
Reprogramação Celular , Epigênese Genética , Células-Tronco Embrionárias Murinas/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Correpressor 2 de Receptor Nuclear/metabolismo , Células-Tronco Pluripotentes/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Acetilação , Animais , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Correpressor 1 de Receptor Nuclear/genética , Correpressor 2 de Receptor Nuclear/genética , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais , Fatores de Tempo
20.
Ann Clin Lab Sci ; 43(2): 135-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23694787

RESUMO

BACKGROUND: Up-regulation of Human Leukocyte Antigen-G (HLA-G) expression is thought to contribute to the escape in immune surveillance by suppressing natural killer (NK) cell function. However, little is known about the expression of HLA-G in hepatocellular carcinoma (HCC) and its relationship to NK cell-mediated cytotoxicity. In this study, we aimed to investigate the expression of HLA-G in human HCC cell lines and determine whether its expression was related to inhibition of NK cell cytolysis. MATERIALS AND METHODS: The levels of HLA-G gene expression in human HCC cell lines were assessed by indirect immunofluorescence analysis (IFA), Real time RT-PCR and Western Blot. Vectors containing small interfering RNA (siRNA) specifically targeting the HLA-G gene were constructed and applied to diminish HLA-G expression. The cells were examined by flow cytometry and fluorescent microscope 24 h after transfection as well as 2-3 weeks after G418 selection. The steady-state levels of HLA-G mRNA and protein were then checked by real time RT-PCR and Western Blot analysis, respectively. A nonradioactive cytotoxicity assay was used to evaluate the effect of HLA-G on NK-mediated cytotoxicity against the siRNA treated cells. RESULTS: Both HLA-G mRNA and protein can be detected in human HCC cell lines. Levels of HLA-G mRNA and protein were diminished 88.73% and 75.91% respectively by targeting siRNA. In the stable HLA-G gene knock-down cell lines, a significant increase in NK cell-mediated lysis occurred. CONCLUSIONS: Abnormal expression of HLA-G in HCC cell lines plays an important role in protecting against NK cell attack. The significant correlation between HLA-G expression and NK cell lysis implies that the abnormal expression of HLA-G might contribute to the mechanism of escape from host immune surveillance in HCC.


Assuntos
Carcinoma Hepatocelular/imunologia , Antígenos HLA-G/imunologia , Vigilância Imunológica/imunologia , Células Matadoras Naturais/imunologia , Neoplasias Hepáticas/imunologia , Western Blotting , Linhagem Celular Tumoral , Testes Imunológicos de Citotoxicidade , Primers do DNA/genética , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Técnicas de Silenciamento de Genes , Antígenos HLA-G/genética , Antígenos HLA-G/metabolismo , Humanos , Interferência de RNA , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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