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1.
Immunity ; 47(3): 538-551.e5, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28930662

RESUMO

Follicular regulatory T (Tfr) cells differentiate from conventional regulatory T (Treg) cells and suppress excessive germinal center (GC) responses by acting on both GC B cells and T follicular helper (Tfh) cells. Here, we examined the impact of mTOR, a serine/threonine protein kinase that senses and integrates diverse environmental cues, on the differentiation and functional competency of Tfr cells in response to protein immunization or viral infection. By genetically deleting Rptor or Rictor, essential components for mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2), respectively, we found that mTORC1 but not mTORC2 is essential for Tfr differentiation. Mechanistically, mTORC1-mediated phosphorylation of the transcription factor STAT3 induced the expression of the transcription factor TCF-1 by promoting STAT3 binding to the Tcf7 5'-regulatory region. Subsequently, TCF-1 bound to the Bcl6 promoter to induce Bcl6 expression, which launched the Tfr cell differentiation program. Thus, mTORC1 initiates Tfr cell differentiation by activating the TCF-1-Bcl-6 axis during immunization or infection.


Assuntos
Imunomodulação , Complexos Multiproteicos/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Biomarcadores , Diferenciação Celular/imunologia , Análise por Conglomerados , Perfilação da Expressão Gênica , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Imunização , Imunofenotipagem , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Transgênicos , Complexos Multiproteicos/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Linfócitos T Reguladores/citologia , Serina-Treonina Quinases TOR/genética
2.
Exp Cell Res ; 425(1): 113537, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36858343

RESUMO

Aberrant regulation of ubiquitination is an essential fundamental process in tumors, especially intrahepatic cholangiocarcinoma (iCCA). We reported that OTUB2, an OTU deubiquitinase, is upregulated in iCCA and stabilizes the CTNNB1-ZEB1 axis, resulting in epithelial-mesenchymal transition (EMT) and iCCA metastasis. Mechanistically, OTUB2 promotes CTNNB1 expression by interacting with the E3 ligase TRAF6. OTUB2 inhibits the lysosomal degradation of CTNNB1 by interacting with TRAF6 and thus regulates the progression of iCCA through ZEB1. Clinically, high OTUB2 expression is related to increased ZEB1 expression and activity and reduced overall survival in iCCA patients. Therefore, advanced iCCA patients may benefit from drugs targeting OTUB2 and its pathway.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Fator 6 Associado a Receptor de TNF/metabolismo , Colangiocarcinoma/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/metabolismo , Enzimas Desubiquitinantes/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Tioléster Hidrolases/metabolismo
3.
Cell Mol Life Sci ; 80(9): 242, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37552373

RESUMO

Radiotherapy resistance is a major obstacle to nasopharyngeal carcinoma (NPC) therapy and contributes to tumour recurrence and metastasis. Lipid metabolism is a key regulatory mechanism in cancer biology; however, its role in NPC radiotherapy resistance remains unclear. In this study, we identified hypoxia-inducible lipid droplet-associated protein (HILPDA) as a newly discovered regulator of radioresistance that induces not only lipid droplet (LD) formation but also intracellular lipid remodelling, notably changing mitochondrial cardiolipin (CL) levels. Additionally, we found that the upregulation of CL promotes mitophagy in response to irradiation exposure. Mechanistically, HILPDA inhibits PINK1-mediated CLS1 ubiquitination and degradation. The combination of a mitophagy inhibitor and irradiation significantly increases the radiosensitivity of NPC cells. Human cancer-derived data confirmed that the HILPDA-CLS1 pathway promotes NPC radioresistance. Collectively, these findings suggest that HILPDA plays a critical role in promoting NPC radioresistance and might be targeted to overcome radiotherapeutic resistance in NPC patients in the clinic.


Assuntos
Neoplasias Nasofaríngeas , Proteínas de Neoplasias , Humanos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Lipidômica , Mitofagia , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/patologia , Proteínas de Neoplasias/genética
4.
Anal Chem ; 95(17): 6854-6862, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37027485

RESUMO

Breakthroughs in immune checkpoint inhibitor (ICI) therapy have revolutionized clinical tumor therapy. Immunohistochemistry (IHC) analysis of PD-L1 in tumor tissue has been used to predict the response to tumor immunotherapy, but the results are not reproducible, and IHC is invasive and cannot be used to monitor the dynamic changes in PD-L1 expression during treatment. Monitoring the expression level of the PD-L1 protein on exosomes (exosomal PD-L1) is promising for both tumor diagnosis and tumor immunotherapy. Here, we established an aptamer-bivalent-cholesterol-anchor assembly of DNAzyme (ABCzyme) analytical strategy that can directly detect exosomal PD-L1 with a minimum lower limit of detection of 5.21 pg/mL. In this way, we found that the levels of exosomal PD-L1 are significantly elevated in the peripheral blood of patients with progressive disease. The precise analysis of exosomal PD-L1 by the proposed ABCzyme strategy provides a potentially convenient method for the dynamic monitoring of tumor progression in patients who receive immunotherapy and proves to be a potential and effective liquid biopsy method for tumor immunotherapy.


Assuntos
DNA Catalítico , Neoplasias , Humanos , Antígeno B7-H1/metabolismo , Imunoterapia/métodos , Imuno-Histoquímica
5.
Small ; 18(27): e2201298, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35652504

RESUMO

Cancer immunotherapy has great potential in tumor eradication and metastasis suppression. However, systemic administration of immune adjuvants and inadequate specificity in cancer treatment, lead to restricted therapeutic benefits and potential immune-related side effects in clinical settings. In this report, the synthesis of various lengths of heptamethine cyanine small molecules to act as multifunctional photosensitizers (PS) for tumor-specific accumulation, near-infrared (NIR) fluorescent imaging, and photodynamic/photothermal/immunotherapy is optimized. In particular, it is demonstrated that C8, which contains eight carbons on two N-alkyl side chains, efficiently self-assembles with albumin to form nanosized dye-albumin complexes. This feature facilitates C8 in vivo self-assembly to remarkably improve its water-solubility, NIR fluorescent emission, long-term blood circulation, as well as tumor-specific accumulation. More importantly, C8 not only exhibits a superior phototherapeutic effect on primary tumors, but also elicits secretion of damage associated molecular patterns, cytokine secretion, dendritic cell maturation, and cytotoxic T lymphocytes activation, ultimately triggering a sufficient antitumor immune response to suppress growths of distant and metastatic tumors. Hence, this multifunctional small molecular PS is characterized with excellent tumor-preferential accumulation, imaging-guided laser irradiation, and phototherapy-induced in situ antitumor immune response, providing a prospective future of its use in tumor-targeting immunotherapy.


Assuntos
Nanopartículas , Neoplasias , Albuminas , Linhagem Celular Tumoral , Corantes , Humanos , Imunoterapia , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia/métodos , Estudos Prospectivos
6.
Nature ; 537(7620): 412-428, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27501245

RESUMO

During chronic viral infection, virus-specific CD8(+) T cells become exhausted, exhibit poor effector function and lose memory potential. However, exhausted CD8(+) T cells can still contain viral replication in chronic infections, although the mechanism of this containment is largely unknown. Here we show that a subset of exhausted CD8(+) T cells expressing the chemokine receptor CXCR5 has a critical role in the control of viral replication in mice that were chronically infected with lymphocytic choriomeningitis virus (LCMV). These CXCR5(+) CD8(+) T cells were able to migrate into B-cell follicles, expressed lower levels of inhibitory receptors and exhibited more potent cytotoxicity than the CXCR5(-) [corrected] subset. Furthermore, we identified the Id2-E2A signalling axis as an important regulator of the generation of this subset. In patients with HIV, we also identified a virus-specific CXCR5(+) CD8(+) T-cell subset, and its number was inversely correlated with viral load. The CXCR5(+) subset showed greater therapeutic potential than the CXCR5(-) [corrected] subset when adoptively transferred to chronically infected mice, and exhibited synergistic reduction of viral load when combined with anti-PD-L1 treatment. This study defines a unique subset of exhausted CD8(+) T cells that has a pivotal role in the control of viral replication during chronic viral infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Centro Germinativo/citologia , Coriomeningite Linfocítica/imunologia , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/imunologia , Receptores CXCR5/metabolismo , Transferência Adotiva , Animais , Linfócitos B/imunologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/transplante , Diferenciação Celular , Doença Crônica , Feminino , Centro Germinativo/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Proteína 2 Inibidora de Diferenciação/metabolismo , Vírus da Coriomeningite Linfocítica/crescimento & desenvolvimento , Masculino , Camundongos , Receptores CXCR5/deficiência , Transdução de Sinais , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/transplante , Carga Viral/imunologia , Replicação Viral/imunologia
7.
Exp Cell Res ; 395(2): 112238, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822724

RESUMO

Human class I homeobox A13 (HOXA13) was initially identified as a transcription factor and has an important role in embryonic development and malignant transformation. However, the clinical significance and the molecular mechanisms of HOXA13 in colon cancer development and progression are still unknown. In this study, we found that HOXA13 was highly expressed in colon cancer tissues, and its expression was associated with histological grade, T stage, N stage and tumour size. In vitro studies showed that HOXA13 promoted colon cancer cell proliferation, migration and invasion. Bioinformatics analysis revealed that HOXA13 expression was positively correlated with the WNT signalling pathway. In vitro studies showed that HOXA13 promoted the malignant phenotype of colon cancer cells by facilitating the nuclear translocation of ß-Catenin. Moreover, XAV939, an inhibitor of ß-Catenin, reversed the HOXA13-mediated effects on invasion and proliferation of colon cancer cells. In vivo studies further verified that HOXA13 promoted tumour formation through the Wnt/ß-Catenin pathway. Collectively, these results suggest that HOXA13 is a potential oncogene that functions by promoting the nuclear translocation of ß-Catenin, thereby maintaining the proliferation and metastasis of colon cancer.


Assuntos
Neoplasias do Colo/metabolismo , Proteínas de Homeodomínio/metabolismo , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Colo/metabolismo , Neoplasias do Colo/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos
8.
Oral Dis ; 26(2): 285-294, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31830347

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of dose-modified docetaxel plus cisplatin and 5-fluorouracil (TPF) in Chinese patients with squamous cell carcinoma of the head and neck (SCCHN). MATERIALS AND METHODS: This Phase III, open-label, multi-center study included Chinese adults with previously untreated TNM Stage III or IV SCCHN (NCT00995293). Patients were randomized (1:1) to induction chemotherapy with TPF (docetaxel 60 mg/m2 and cisplatin 60 mg/m2 on day 1 and 5-FU 750 mg/m2  per day continuous IV infusion on days 1-5) or PF (cisplatin 75 mg/m2 on day 1 and 5-FU 750 mg/m2  per day on days 1-5) every 3 weeks for 3-4 cycles. The primary endpoint was progression-free survival (PFS). RESULTS: Median PFS in the TPF (n = 108) and PF (n = 111) groups was 400 days and 342 days (HR = 0.75; 95% CI, 0.53─1.06; p = .227), respectively. Overall response rate was higher for TPF versus PF (76.3% vs. 52.9%; p = .001), although this equalized following radiotherapy (75.0% vs. 73.9%). In the TPF and PF groups, ≥1 treatment-emergent adverse event was experienced by 104 (94.5%) and 110 (93.2%) patients, respectively. CONCLUSION: Adding dose-modified docetaxel to PF did not significantly improve PFS but may increase anti-tumor activity in Chinese patients with locally advanced SCCHN.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Docetaxel/administração & dosagem , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Terapia Neoadjuvante , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Adolescente , Adulto , Idoso , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Taxoides/administração & dosagem , Adulto Jovem
9.
Gut ; 67(2): 307-319, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-27849558

RESUMO

OBJECTIVE: As the modulation of autophagic processes can be therapeutically beneficial to cancer treatment, the identification of novel autophagic enhancers is highly anticipated. However, current autophagy-inducing anticancer agents exert undesired side effects owing to their non-specific biodistribution in off-target tissues. This study aims to develop a multifunctional agent to integrate cancer targeting, imaging and therapy and to investigate its mechanism. DESIGN: A series of mitochondria-targeting near-infrared (NIR) fluorophores were synthesised, screened and identified for their autophagy-enhancing activity. The optical properties and biological effects were tested both in vitro and in vivo. The underlying mechanism was investigated using inhibitors, small interfering RNA (siRNA), RNA sequencing, mass spectrometry and human samples. RESULTS: We have screened and identified a new NIR autophagy-enhancer, IR-58, which exhibits significant tumour-selective killing effects. IR-58 preferentially accumulates in the mitochondria of colorectal cancer (CRC) cells and xenografts, a process that is glycolysis-dependent and organic anion transporter polypeptide-dependent. IR-58 kills tumour cells and induces apoptosis via inducing excessive autophagy, which is mediated through the reactive oxygen species (ROS)-Akt-mammalian target of rapamycin (mTOR) pathway. RNA sequencing, mass spectrometry and siRNA interference studies demonstrate that translocase of inner mitochondrial membrane 44 (TIM44)-superoxide dismutase 2 (SOD2) pathway inhibition is responsible for the excessive ROS, autophagy and apoptosis induced by IR-58. TIM44 expression correlates positively with CRC development and poor prognosis in patients. CONCLUSIONS: A novel NIR small-molecule autophagy-enhancer, IR-58, with mitochondria-targeted imaging and therapy capabilities was developed for CRC treatment. Additionally, TIM44 was identified for the first time as a potential oncogene, which plays an important role in autophagy through the TIM44-SOD2-ROS-mTOR pathway.


Assuntos
Autofagia/efeitos dos fármacos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Corantes Fluorescentes/farmacologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Fluorescência , Corantes Fluorescentes/uso terapêutico , Células HCT116 , Células HT29 , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Proteínas de Transporte da Membrana Mitocondrial , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Fenômenos Ópticos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Superóxido Dismutase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Mol Ther ; 25(5): 1248-1258, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28366766

RESUMO

Chimeric antigen receptor T (CAR-T) cells have shown promising efficacy in treatment of hematological malignancies, but its applications in solid tumors need further exploration. In this study, we investigated CAR-T therapy targeting carcino-embryonic antigen (CEA)-positive colorectal cancer (CRC) patients with metastases to evaluate its safety and efficacy. Five escalating dose levels (DLs) (1 × 105 to 1 × 108/CAR+/kg cells) of CAR-T were applied in 10 CRC patients. Our data showed that severe adverse events related to CAR-T therapy were not observed. Of the 10 patients, 7 patients who experienced progressive disease (PD) in previous treatments had stable disease after CAR-T therapy. Two patients remained with stable disease for more than 30 weeks, and two patients showed tumor shrinkage by positron emission tomography (PET)/computed tomography (CT) and MRI analysis, respectively. Decline of serum CEA level was apparent in most patients even in long-term observation. Furthermore, we observed persistence of CAR-T cells in peripheral blood of patients receiving high doses of CAR-T therapy. Importantly, we observed CAR-T cell proliferation especially in patients after a second CAR-T therapy. Taken together, we demonstrated that CEA CAR-T cell therapy was well tolerated in CEA+ CRC patients even in high doses, and some efficacy was observed in most of the treated patients.


Assuntos
Adenocarcinoma/terapia , Antígeno Carcinoembrionário/genética , Neoplasias Colorretais/terapia , Neoplasias Hepáticas/terapia , Recidiva Local de Neoplasia/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/imunologia , Adenocarcinoma/secundário , Idoso , Antígeno Carcinoembrionário/imunologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Citotoxicidade Imunológica , Relação Dose-Resposta Imunológica , Feminino , Expressão Gênica , Humanos , Imunoterapia Adotiva , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário , Ativação Linfocitária , Depleção Linfocítica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/imunologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Engenharia de Proteínas , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/citologia , Linfócitos T/transplante
11.
J Pineal Res ; 63(1)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28247536

RESUMO

Cellular senescence is an important tumor-suppressive mechanism. However, acquisition of a senescence-associated secretory phenotype (SASP) in senescent cells has deleterious effects on the tissue microenvironment and, paradoxically, promotes tumor progression. In a drug screen, we identified melatonin as a novel SASP suppressor in human cells. Strikingly, melatonin blunts global SASP gene expression upon oncogene-induced senescence (OIS). Moreover, poly(ADP-ribose) polymerase-1 (PARP-1), a sensor of DNA damage, was identified as a new melatonin-dependent regulator of SASP gene induction upon OIS. Here, we report two different but potentially coherent epigenetic strategies for melatonin regulation of SASP. The interaction between the telomeric repeat-containing RNA (TERRA) and PARP-1 stimulates the SASP, which was attenuated by 67.9% (illustrated by the case of IL8) by treatment with melatonin. Through binding to macroH2A1.1, PARP-1 recruits CREB-binding protein (CBP) to mediate acetylation of H2BK120, which positively regulates the expression of target SASP genes, and this process is interrupted by melatonin. Consequently, the findings provide novel insight into melatonin's epigenetic role via modulating PARP-1 in suppression of SASP gene expression in OIS-induced senescent cells. Our studies identify melatonin as a novel anti-SASP molecule, define PARP-1 as a new target by which melatonin regulates SASP, and establish a new epigenetic paradigm for a pharmacological mechanism by which melatonin interrupts PARP-1 interaction with the telomeric long noncoding RNA(lncRNA) or chromatin.


Assuntos
Senescência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Melatonina/farmacologia , Poli(ADP-Ribose) Polimerase-1/metabolismo , Linhagem Celular , Células Cultivadas , Senescência Celular/genética , Fibroblastos/metabolismo , Humanos , Pulmão/citologia , Poli(ADP-Ribose) Polimerase-1/genética
13.
J Biol Chem ; 290(41): 25151-63, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26306033

RESUMO

Brown adipocytes function to dissipate energy as heat through adaptive thermogenesis. Understanding the molecular mechanisms underlying the brown fat thermogenic program may provide insights for the development of therapeutic approaches in the treatment of obesity. Most studies investigating the mechanisms underlying brown fat development focus on genetic mechanisms; little is known about the epigenetic mechanisms in this process. We have discovered that ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX), a histone demethylase for di- or tri-methylated histone 3 lysine 27 (H3K27me2/3), plays a potential role in regulating brown adipocyte thermogenic program. We found that UTX is up-regulated during brown adipocyte differentiation and by cold exposure in both brown adipose tissue (BAT) and white adipose tissue (WAT) of mice, suggesting a potential role in thermogenesis. Inactivation of UTX down-regulates brown fat specific gene expression, while overexpression of UTX does the opposite. Notably, activation of ß adrenergic signaling recruits UTX to the UCP1 and PGC1α promoters, leading to decreased H3K27me3, a histone transcriptional repressive mark. UTX demethylates H3K27me3 and subsequently interacts with the histone acetyltransferase (HAT) protein CBP, resulting in increased H3K27 acetylation (H3K27ac), a histone transcriptional active mark. UTX positively regulate brown adipocyte thermogenic program through coordinated control of demethylating H3K27me3 and acetylating H3K27, switching the transcriptional repressive state to the transcriptional active state at the promoters of UCP1 and PGC1α. We conclude that UTX may play a potential role in regulation of brown adipocyte gene expression and may mediate ß adrenergic activation of brown fat function.


Assuntos
Adipócitos Marrons/metabolismo , Histona Desmetilases/metabolismo , Histonas/química , Histonas/metabolismo , Lisina/metabolismo , Termogênese , Acetilação , Adipócitos Marrons/citologia , Animais , Proteína de Ligação a CREB/metabolismo , Diferenciação Celular , Linhagem Celular , Temperatura Baixa , Proteína Potenciadora do Homólogo 2 de Zeste , Regulação Enzimológica da Expressão Gênica , Histona Desmetilases/genética , Canais Iônicos/genética , Metabolismo dos Lipídeos , Masculino , Potencial da Membrana Mitocondrial , Metilação , Camundongos , Proteínas Mitocondriais/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Proteína Desacopladora 1
14.
Clin Sci (Lond) ; 128(8): 493-506, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25431838

RESUMO

Over-nutrition induces low-grade inflammation that dampens insulin sensitivity, but the underlying molecular mediators are not fully understood. Comparative gene identification-58 (CGI-58) is an intracellular lipolytic activator. In the present study, we show that in mouse visceral fat-derived macrophages or human peripheral blood monocytes, CGI-58 negatively and interleukin (IL)-1ß positively correlate with obesity. Saturated non-esterified fatty acid (NEFA) suppresses CGI-58 expression in macrophages and this suppression activates FOXO1 (forkhead box-containing protein O subfamily-1) through inhibition of FOXO1 phosphorylation. Activated FOXO1 binds to an insulin-responsive element in IL-1ß promoter region to potentiate IL-1ß transcription. Gain- and loss-of-function studies demonstrate that NEFA-induced CGI-58 suppression activates FOXO1 to augment IL-1ß transcription by dampening insulin signalling through induction of SOCS3 (suppressor of cytokine signalling 3) expression. CGI-58 deficiency-induced SOCS3 expression is NLRP3 (nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3) inflammasome-dependent. Our data thus identified a vicious cycle (IL-1ß-SOCS3-FOXO1-IL-1ß) that amplifies IL-1ß secretion and is initiated by CGI-58 deficiency-induced activation of the NLRP3 inflammasome in macrophages. We further show that blocking this cycle with a FOXO1 inhibitor, an antioxidant that inhibits FOXO1 or IL-1 receptor antagonist alleviates chronic inflammation and insulin resistance in high-fat diet (HFD)-fed mice. Collectively, our data suggest that obesity-associated factors such as NEFA and lipopolysaccharide (LPS) probably adopt this vicious cycle to promote inflammation and insulin resistance.


Assuntos
1-Acilglicerol-3-Fosfato O-Aciltransferase/deficiência , Fatores de Transcrição Forkhead/metabolismo , Interleucina-1beta/genética , Macrófagos/metabolismo , Transdução de Sinais , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Transcrição Gênica , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Animais , Índice de Massa Corporal , Dieta Hiperlipídica , Ácidos Graxos/farmacologia , Proteína Forkhead Box O1 , Humanos , Inflamassomos/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Modelos Biológicos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteína 3 Supressora da Sinalização de Citocinas , Transcrição Gênica/efeitos dos fármacos , Aumento de Peso
15.
Immunol Invest ; 44(2): 147-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25122543

RESUMO

CD8(+)CD62L(+) T cells have been shown to play pivotal roles in anti-viral immunity, chronic myeloid leukemia and renal cell carcinoma. Recently, CD8(+)CD62L(+) T cells from naïve mice (nCD8(+)CD62L(+) T cells) have shown superior anti-tumor properties in melanoma-bearing mice. Considering that antigen-specific memory T cells have shown to possess more potent immunity than non-specific memory T cells, we hypothesized that CD8(+)CD62L(+) T cells from tumor-bearing individuals (mCD8(+)CD62L(+) T cells) might have superior anti-tumor effect than nCD8(+)CD62L(+) T cells. Therefore, we investigated phenotypes, functions and the in vivo distribution of mCD8(+)CD62L(+) T cells in tumor-bearing mice. We found that, while keeping the features of central memory T cells, the frequency of mCD8(+)CD62L(+) T cell in the spleen of tumor-bearing mice was significantly higher than that the one of nCD8(+)CD62L(+) T cell in naive mice. Moreover, we demonstrated that mCD8(+)CD62L(+) T cells had higher proliferation rate and IFN-γ production than nCD8(+)CD62L(+) T cells, in vitro. We performed adoptive transfer of mCD8(+)CD62L(+) T cells into melanoma-bearing mice and tracked them in spleen, lymph nodes and in melanoma tissues. Our results show that mCD8(+)CD62L(+) T cells had stronger in vivo anti-tumoral activity than nCD8(+)CD62L(+) T cells. This study highlights the therapeutic potential of mCD8(+)CD62L(+) T cells in the immunotherapy of melanoma and possibly other tumors.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Selectina L/metabolismo , Melanoma/imunologia , Melanoma/metabolismo , Animais , Antígenos de Superfície/metabolismo , Apoptose/imunologia , Biomarcadores , Modelos Animais de Doenças , Feminino , Imunofenotipagem , Imunoterapia Adotiva , Interferon gama/biossíntese , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Melanoma/patologia , Melanoma/terapia , Camundongos , Fenótipo , Baço/citologia , Baço/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
16.
Carcinogenesis ; 35(7): 1661-70, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24743511

RESUMO

Recent evidence has been suggesting the important roles of endothelial cells (ECs) involved in the pathogenesis of several cancers, including colorectal carcinomas (CRCs), but the underlying mechanism remains elusive. We have demonstrated previously that CRC-derived fibronectin extra domain A (EDA) promotes vasculogenesis, tumorigenesis and metastasis of CRCs. At the current study, we showed that EC-secreted EDA promotes the metastatic capacity CRC cells via inducing an epithelial-mesenchymal transition. In vitro and in vivo experiments showed that EC-secreted EDA, via the interaction with integrin α9ß1 on neighboring CRC cells, leads to the activation of focal adhesion kinase as well as Rac signalings, thus strengthens the polarity of cytoskeleton and promotes the invasion capacity of CRC cells. Furthermore, Erk signaling pathway was revealed to critically mediate the effect of EC-derived EDA on CRC cells. Our findings reveal a novel oncogenic role of ECs in promoting CRC malignancy through secreting EDA.


Assuntos
Neoplasias Colorretais/patologia , Endotélio Vascular/patologia , Transição Epitelial-Mesenquimal , Fibronectinas/metabolismo , Neoplasias Hepáticas/secundário , Animais , Western Blotting , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Endotélio Vascular/metabolismo , Fibronectinas/genética , Imunofluorescência , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Integrinas/genética , Integrinas/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
17.
Biochim Biophys Acta ; 1833(12): 2996-3005, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23954443

RESUMO

Phosphate-activated mitochondrial glutaminase (GLS2) is suggested to be linked with elevated glutamine metabolism. It plays an important role in catalyzing the hydrolysis of glutamine to glutamate. The present study was to investigate the potent effect of GLS2 on radioresistance of cervical carcinoma. GLS2 was examined in 144 cases of human cervical cancer specimens (58 radioresistant specimens, 86 radiosensitive specimens) and 15 adjacent normal cervical specimens with immunohistochemistry. HeLa cells were treated with a cumulative dose of 50Gy X-rays, over 6months, yielding the resistant sub-line HeLaR. The expressions of GLS2 were measured by Western blot. Radioresistance was tested by colony survival assay. Apoptosis was determined by flow cytometry. The levels of glutathione (GSH), reactive oxygen species (ROS), NAD(+)/NADH ratio and NADP(+)/NADPH ratio were detected by quantization assay kit. Xenografts were used to confirm the effect of GLS2 on radioresistance in vivo. The expressions of GLS2 were significantly enhanced in tumor tissues of radioresistant patients compared with that in radiosensitive patients. In vitro, the radioresistant cell line HeLaR exhibited significantly increased GLS2 levels than its parental cell line HeLa. GLS2 silenced radioresistant cell HeLaR shows substantially enhanced radiosensitivity with lower colony survival and higher apoptosis in response to radiation. In vivo, xenografts with GLS2 silenced HeLaR were more sensitive to radiation. At the molecular level, knock-down of GLS2 increased the intracellular ROS levels of HeLaR exposed to irradiation by decreasing the productions of antioxidant GSH, NADH and NADPH. GLS2 may have an important role in radioresistance in cervical cancer patients.


Assuntos
Técnicas de Silenciamento de Genes , Glutaminase/metabolismo , Glutationa/metabolismo , NAD/metabolismo , Radiação Ionizante , Neoplasias do Colo do Útero/radioterapia , Animais , Antioxidantes/metabolismo , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Imuno-Histoquímica , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Tolerância a Radiação/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Oncologist ; 19(11): 1169-78, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25223462

RESUMO

BACKGROUND: The EACH study assessed the efficacy of oxaliplatin, 5-fluorouracil, and leucovorin (the FOLFOX4 regimen) compared with doxorubicin alone in terms of overall survival (OS), progression-free survival (PFS), and safety in patients with advanced hepatocellular carcinoma (HCC). We present the results of this study in Chinese patients. METHODS: In a multicenter, open-label, randomized, phase III study (NCT00471965), 371 patients (279 patients from the People's Republic of China) were randomized 1:1 to receive either FOLFOX4 or doxorubicin until disease progression, intolerable toxicity, death, or surgical resection. RESULTS: Baseline characteristics of the Chinese patients enrolled in the study were similar for the 2 treatment groups and in comparison with the whole EACH cohort. Median OS at the prespecified time point of treatment was 5.7 months with FOLFOX4 and 4.3 months with doxorubicin (hazard ratio [HR]: 0.74; 95% confidence interval [CI]: 0.55-0.98; p = .03). At the end of the follow-up period, median OS was 5.9 months with FOLFOX4 and 4.3 months with doxorubicin (HR: 0.75; 95% CI: 0.58-0.98; p = .03). Median PFS was 2.4 months and 1.7 months in the FOLFOX4 and doxorubicin groups, respectively (HR: 0.55; 95% CI: 0.45-0.78; p = .0002). The response rate (RR) and disease control rate (DCR) were significantly higher in the FOLFOX4 group than in the doxorubicin group (RR: 8.6% vs. 1.4%, p = .006; DCR: 47.1% vs. 26.6%, p = .0004). Hematological toxicity was more frequently reported in the FOLFOX4 group. CONCLUSION: For Chinese HCC patients enrolled in the EACH study, FOLFOX4 significantly improved the RR and DCR and prolonged survival compared with doxorubicin. Systemic chemotherapy with oxaliplatin-based regimens may play an important role in the treatment of Chinese patients with advanced HCC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Povo Asiático , Carcinoma Hepatocelular/mortalidade , Feminino , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento
19.
Tumour Biol ; 35(9): 8757-63, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24874053

RESUMO

Genetic variation of interleukin-28B (IL-28B) rs12979860 T/C polymorphism is associated with the immune response to interferon (IFN) therapy, which is applied in the treatment of chronic viral hepatitis induced by hepatitis B virus (HBV) and hepatitis C virus (HCV). These chronic liver diseases could progress to end-stage liver diseases, such as hepatocellular carcinoma (HCC). The aim of this study was to clarify whether there exists a causal association between IL-28B rs12979860 T/C polymorphism and development of HCC. In a meta-analysis of six studies with 850 cases and 811 controls, we summarized the data on the association between IL-28B rs12979860 T/C polymorphism and HCC risk and calculated ORs and 95 % CIs to estimate the association strength. We observed that IL-28B rs12979860 T/C polymorphism was positively associated with overall HCC risk (TT vs. CC: OR = 2.38; 95 %, 1.60-3.55; TT vs CT + CC: OR = 1.79; 95 %, 1.23-2.60). In the stratified analysis by ethnicity, the robust association retained in Caucasians with higher risk among TT carriers relative to the CC carriers. A similar trend was found in the studies of healthy controls when data were stratified by source of controls. The combined data suggest that IL-28B rs12979860 T/C polymorphism seems to augment the risk of developing HCC, especially in Caucasians.


Assuntos
Carcinoma Hepatocelular/genética , Predisposição Genética para Doença/genética , Interleucinas/genética , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único , Povo Asiático/genética , Carcinoma Hepatocelular/etnologia , Carcinoma Hepatocelular/virologia , Progressão da Doença , Predisposição Genética para Doença/etnologia , Genótipo , Vírus de Hepatite/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Interferons , Neoplasias Hepáticas/etnologia , Neoplasias Hepáticas/virologia , Razão de Chances , População Branca/genética
20.
Support Care Cancer ; 22(4): 979-87, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24276953

RESUMO

PURPOSE: Aprepitant, an oral neurokinin-1 receptor antagonist, has demonstrated improved control of chemotherapy-induced nausea and vomiting (CINV) in previous studies. This is the first phase III study to evaluate the efficacy and tolerability of aprepitant in patients receiving highly emetogenic chemotherapy (HEC) in Asian countries. METHODS: This multicenter, double-blind, placebo-controlled trial assessed the prevention of CINV during the acute phase (AP), delayed phase (DP), and overall phase (OP). Patients receiving HEC were randomized to either an aprepitant group (day 1, aprepitant 125 mg; days 2-3, aprepitant 80 mg) or a standard therapy group (days 1-3, placebo). Both groups received intravenous granisetron and oral dexamethasone. The primary end point was complete response (CR; no emesis and no use of rescue therapy) during the OP. RESULTS: Of the 421 randomized patients, 411 (98%) were assessable for efficacy; 69.6% (142/204) and 57.0% (118/207) of patients reported CR during the OP in the aprepitant and standard therapy groups, respectively (P = 0.007). CR rates in the aprepitant group were higher during the DP (74.0% vs. 59.4%, P = 0.001) but were similar during the AP (79.4% vs. 79.3%, P = 0.942). Toxicity and adverse events were comparable in both groups. CONCLUSIONS: The addition of aprepitant to standard antiemetic treatment regimens for Chinese patients undergoing HEC provided superior CINV prevention and was well tolerated.


Assuntos
Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Morfolinas/uso terapêutico , Náusea/prevenção & controle , Vômito/prevenção & controle , Antieméticos/efeitos adversos , Antineoplásicos/uso terapêutico , Aprepitanto , Povo Asiático , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morfolinas/efeitos adversos , Náusea/induzido quimicamente , Vômito/induzido quimicamente
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