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1.
Nat Prod Res ; : 1-12, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693725

RESUMO

The genus Liparis, a group of perennial ornamental herbs in the family Orchidaceae, is widely distributed in tropical and subtropical regions. Many species of the genus Liparis have been commonly used as traditional herbal medicines for the treatment of menorrhagia, haemoptysis, traumatic bleeding, snake bites, and pneumonia. This review describes the ornamental value of plants of the genus Liparis and summarises the chemical constituents and pharmacological activities reported during the last decade. The main chemical constituents of this genus are phenolic acids, alkaloids, flavonoids, etc. Most phenolic acids and alkaloids have a nervogenic acid skeleton, and most alkaloids also have a pyrrolizidine skeleton. Extracts from the genus Liparis plants showed significant haemostatic, antitumor, anti-inflammatory, hypolipidemic, antioxidant, and antibacterial activities. This paper proposed ideas and research directions for the future study of plants in the genus Liparis, providing valuable information for the development of new drugs and promoting their utilisation.

2.
iScience ; 27(1): 108630, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38188529

RESUMO

The role of Epstein-Barr virus (EBV) in lymphoma cells of nodular sclerosis classic Hodgkin lymphoma (NScHL) is controversial. Our aim was to explore this and establish a clinically feasible model for risk stratification. We interrogated data from 542 consecutive subjects with NScHL receiving ABVD therapy and demonstrated EBV-infection in their lymphoma cells with EBV-encoded small RNAs (EBERs) in situ hybridization. Subjects were divided into training and validation datasets. As data from the training dataset suggested EBERs-positivity was the only independent prognostic factor for both progression-free survival (PFS) and overall survival (OS), we developed corresponding prognostic models based on it. Our models showed excellent performance in both training and validation cohort. These data indicate the close association of EBV infection and the outcomes of persons with NScHL receiving ABVD. Additionally, our newly developed models should help physicians estimate prognosis and select individualized therapy.

3.
Cancer Lett ; 584: 216643, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38246220

RESUMO

In the realm of cancer therapeutics and resistance, kinases play a crucial role, particularly in gastric cancer (GC). Our study focused on platinum-based chemotherapy resistance in GC, revealing a significant reduction in homeodomain-interacting protein kinase 3 (HIPK3) expression in platinum-resistant tumors through meticulous analysis of transcriptome datasets. In vitro and in vivo experiments demonstrated that HIPK3 knockdown enhanced tumor proliferation and metastasis, while upregulation had the opposite effect. We identified the myocyte enhancer factor 2C (MEF2C) as a transcriptional regulator of HIPK3 and uncovered HIPK3's role in downregulating the morphogenesis regulator microtubule-associated protein (MAP7) through ubiquitination. Phosphoproteome profiling revealed HIPK3's inhibitory effects on mTOR and Wnt pathways crucial in cell proliferation and movement. A combined treatment strategy involving oxaliplatin, rapamycin, and IWR1-1-endo effectively overcame platinum resistance induced by reduced HIPK3 expression. Monitoring HIPK3 levels could serve as a GC malignancy and platinum resistance indicator, with our proposed treatment strategy offering novel avenues for reversing resistance in gastric cancer.


Assuntos
Platina , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Oxaliplatina/farmacologia , Progressão da Doença , Proliferação de Células , Linhagem Celular Tumoral , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular
4.
Free Radic Biol Med ; 198: 1-11, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36736442

RESUMO

Acidic lysosomes are indispensable for cancer development and linked to chemotherapy resistance. Chloroquine (CQ) and functional analogues have been considered as a potential solution to overcome the cancer progression and chemoresistance by inhibiting the lysosome-mediated autophagy and multidrug exocytosis. However, their anti-cancer efficacy in most clinical trials demonstrated modest improvement. In this study, we investigated the detailed mechanisms underlying the acquired resistance of K562 leukemic cells to CQ treatment. In response to 5-80 µM CQ, the lumen pH of endosomal-lysosomal system immediately increased and gradually reached dynamic equilibrium within 24 h. Leukemic cells produced more acidic organelles to tolerate 5-10 µM CQ. CQ (20-80 µM) concentration-dependently triggered cytosolic pH (pHi) rise, G0/G1 arrest, mitochondrial depolarization/fragmentation, and necrotic/apoptotic cell death. Oxidant induction by CQ was responsible for the mitochondria-dependent cytotoxicity and partial pHi elevation. Cells that survived the CQ cytotoxicity were accompanied with increased mitochondria. Under the 80 µM CQ challenge, co-treatment with the inhibitor of F0 part of mitochondrial H+-ATP synthase, oligomycin (40 nM), prevented the elevation of oxidants as well as pHi, and attenuated stresses on mitochondria, cell survival, and cell proliferation. Besides, oligomycin-treated cells obviously displayed the lysosomal peripheralization and plasma membrane blebbing, suggesting that these cells were in process of lysosomal exocytosis and microvesicle release. Enhanced motion of these secretory processes allowed the cells to exclude CQ and repair necrotic injury. Together, the oxidant production and the proton dynamic interconnection among lysosomes, mitochondria, and cytosol are crucial for leukemic susceptibility to lysosomotropic chemotherapeutics.


Assuntos
Apoptose , Cloroquina , Humanos , Cloroquina/farmacologia , Necrose/metabolismo , Linhagem Celular Tumoral , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Oligomicinas , Concentração de Íons de Hidrogênio , Autofagia
5.
Genome Med ; 13(1): 146, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493320

RESUMO

BACKGROUND: Epstein-Barr virus (EBV)-associated gastric carcinomas (EBVaGCs) present unique molecular signatures, but the tumorigenesis of EBVaGCs and the role EBV plays during this process remain poorly understood. METHODS: We applied whole-exome sequencing, EBV genome sequencing, and whole-genome bisulfite sequencing to multiple samples (n = 123) derived from the same patients (n = 25), which covered saliva samples and different histological stages from morphologically normal epithelial tissues to dysplasia and EBVaGCs. We compared the genomic landscape between EBVaGCs and their precursor lesions and traced the clonal evolution for each patient. We also analyzed genome sequences of EBV from samples of different histological types. Finally, the key molecular events promoting the tumor evolution were demonstrated by MTT, IC50, and colony formation assay in vitro experiments and in vivo xenograft experiments. RESULTS: Our analysis revealed increasing mutational burden and EBV load from normal tissues and low-grade dysplasia (LD) to high-grade dysplasia (HD) and EBVaGCs, and oncogenic amplifications occurred late in EBVaGCs. Interestingly, within each patient, EBVaGCs and HDs were monoclonal and harbored single-strain-originated EBV, but saliva or normal tissues/LDs had different EBV strains from that in EBVaGCs. Compared with precursor lesions, tumor cells showed incremental methylation in promotor regions, whereas EBV presented consistent hypermethylation. Dominant alterations targeting the PI3K-Akt and Wnt pathways were found in EBV-infected cells. The combinational inhibition of these two pathways in EBV-positive tumor cells confirmed their synergistic function. CONCLUSIONS: We portrayed the (epi) genomic evolution process of EBVaGCs, revealed the extensive genomic diversity of EBV between tumors and normal tissue sites, and demonstrated the synergistic activation of the PI3K and Wnt pathways in EBVaGCs, offering a new potential treatment strategy for this disease.


Assuntos
Carcinoma/genética , Infecções por Vírus Epstein-Barr/genética , Genômica , Herpesvirus Humano 4/genética , Neoplasias Gástricas/genética , Animais , Linhagem Celular Tumoral , Metilação de DNA , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Oncogenes , Fosfatidilinositol 3-Quinases/genética , Filogenia , Neoplasias Gástricas/patologia , Sequenciamento Completo do Genoma
6.
J Oncol ; 2021: 8890715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34104194

RESUMO

Centrosomal protein 55 (CEP55) is a centrosome- and midbody-associated protein that is overexpressed in several cancers. However, the underlying molecular mechanism of CEP55-mediated progression and metastasis of esophageal squamous cell carcinoma (ESCC) is not clear. In the current study, we detected CEP55 mRNA by qRT-PCR while protein expression was detected by western blot analysis and immunohistochemistry (IHC). In addition, we knocked down CEP55 and investigated the ability of CEP55 to affect colony formation and migration. Here, we report that CEP55 mRNA and protein expression was significantly increased in ESCC. IHC staining showed that CEP55 expression correlated with TNM stage (p=0.046) and lymph node metastases (p=0.024). According to overall survival (OS) and disease-free survival (DFS), patients whose tumors expressed a higher level of CEP55 had a poorer prognosis than those with low expression level of CEP55. A multivariate analysis revealed that CEP55 expression was an independent prognostic indicator for patients with ESCC. Knockdown of CEP55 decreased the colony formation ability and migration of ESCC cells and also reduced the phosphorylation of Src, FAK, and ERK. Therefore, our study implied that CEP55 may be a valuable biomarker and a potential target in the treatment of patients with ESCC.

7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(3): 722-726, 2018 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29950210

RESUMO

OBJECTIVE: To detect the serum levels of platelet microparticle (PMP), fibronectin (FN), and von Willebrand Factor (vWF) in acute leukemia (AL) patients with thrombocytopenic and to analyze the relationship of the serum levels of PMP, FN and vWF with bleeding degree. METHODS: One hundred and one newly diagnosed AL patients from May 2014 to May 2017 were enrolled the AL group. According to the WHO standard of bleeding stratification, 101 AL patients were divided into 5 sub groups: 0, 1, 2, 3 and 4 score groups; 52 normal persons subjected to physical examination were enrolled in control group. The PMP level was detected by flow cytometry; the FN and vWF levels were detected by ELISA. The levels of PMP, FN and vWF were compared between the AL group and the control group. The serum levels of PMP, FN and vWF were compared according to bleeding degree group. The relationship of bleeding degree with the serum levels of PMP, FN and vWF was analyzed. RESULTS: The patients with newly diagnosed acute leukemia aged 18 to 60, and accounted for 61.39%. The degree of bleeding was mainly 1 score, which accounted for 38.61%. The serum levels of PMP, vWF and FN AL groups were significantly higher than those in control group (6.06%±4.38% vs 0.89%±0.50%, 205.82±24.89 vs 58.04±13.35 µg/L, 398.29±46.93 vs 311.37±26.02 µg/L)(P<0.001). The serum levels of PMP, FN and vWF were different among 5 subgroup (P<0.01); the level of PMP and FN were the highest in 0 score group and the lowest in 4 score group; the vWF level was the highest in 4 score groups and the lowest in 0 score group. The bleeding degree in the patients with acute leukemia negatively correlated with PMP level, and positively with NF and vWF levels (r=-0.753, r=0.648, r=0.805). CONCLUSION: According to the relationship of the bleeding degree with serum levels of PMP, FN, vWF in patients, the detection of PMP, vWF and FN levels can help to evaluale the bleeding degree in the patients.


Assuntos
Leucemia , Doença Aguda , Adolescente , Adulto , Micropartículas Derivadas de Células , Hemorragia , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Fator de von Willebrand
8.
Cancer Lett ; 414: 294-300, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29107111

RESUMO

Cisplatin resistance frequently occurs in esophageal squamous cell carcinoma (ESCC). The underlying mechanism for cisplatin resistance in ESCC remains largely obscure. Here we report that entinostat reversed cisplatin resistance in ESCC both in vitro and in vivo by induction of apoptosis and inhibition of cell proliferation, accompanied by a decrease of multidrug resistance gene 1 (MDR1), P-Src, Mcl-1, Cyclin D1 and an increase of cleaved PARP. MDR1 expression was associated with worsen survival of ESCC patients with cisplatin-based chemotherapy. Dasatinib potentiated entinostat to overcome cisplatin resistance. By inhibiting Src, dasatinib reduced the expression of MDR1 and Mcl-1. Furthermore, Obatoclax, an inhibitor of Mcl-1, obviously decreased the expression of MDR1, suggesting that entinostat might surmount cisplatin resistance in ESCC via a Src-Mcl-1-MDR1 pathway. Interestingly, cisplatin also enhanced the effect of entinostat both in vitro and in vivo. Our data disclose a molecular basis that entinostat reverses cisplatin resistance, and provide a promising strategy with combinatorial drugs to treat cisplatin resistant ESCC patients.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Esofágicas/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adulto , Idoso , Animais , Benzamidas/administração & dosagem , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Regulação para Baixo/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Piridinas/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Nat Commun ; 8(1): 524, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900112

RESUMO

Esophageal squamous dysplasia is believed to be the precursor lesion of esophageal squamous cell carcinoma (ESCC); however, the genetic evolution from dysplasia to ESCC remains poorly understood. Here, we applied multi-region whole-exome sequencing to samples from two cohorts, 45 ESCC patients with matched dysplasia and carcinoma samples, and 13 tumor-free patients with only dysplasia samples. Our analysis reveals that dysplasia is heavily mutated and harbors most of the driver events reported in ESCC. Moreover, dysplasia is polyclonal, and remarkable heterogeneity is often observed between tumors and their neighboring dysplasia samples. Notably, copy number alterations are prevalent in dysplasia and persist during the ESCC progression, which is distinct from the development of esophageal adenocarcinoma. The sharp contrast in the prevalence of the 'two-hit' event on TP53 between the two cohorts suggests that the complete inactivation of TP53 is essential in promoting the development of ESCC.The pathogenesis of oesophageal squamous cell carcinoma is a multi-step process but the genetic determinants behind this progression are unknown. Here the authors use multi-region exome sequencing to comprehensively investigate the genetic evolution of precursor dysplastic lesions and untransformed oesophagus.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Exoma , Mutação , Lesões Pré-Cancerosas/genética , Variações do Número de Cópias de DNA , Carcinoma de Células Escamosas do Esôfago , Humanos , Perda de Heterozigosidade , Lesões Pré-Cancerosas/patologia , Análise de Sequência de DNA/métodos , Proteína Supressora de Tumor p53/genética
10.
J Transl Med ; 15(1): 37, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28202073

RESUMO

BACKGROUND: Macrophages (Mφs) constitute a major component of the leukocyte infiltrate and perform distinct roles in different tumor microenvironments. This study aimed to characterize the distribution, composition and prognostic value of Mφs in hepatocellular carcinoma (HCC) and gastric cancer (GC). METHODS: Immunohistochemistry and immunofluorescence were used to identify Mφ subsets in HCC and GC tissues. Kaplan-Meier analysis and Cox regression models were applied to estimate the overall survival (OS) for HCC and GC patients. RESULTS: The results showed that the density of Mφs decreased in the intra-tumor region (IT) of HCC, but remarkably increased in the IT of GC, as compared with their non-tumor regions (NT). In HCC, most CD68+ Mφs were CD204+ and CD169+ cells in the NT region; however, there was a significant decrease in the percentage of CD169+ Mφ in the IT region. In contrast, CD68+ Mφs comprised a smaller percentage of CD204+ than the CD169+ subpopulation in the NT region, while more CD204+ but fewer CD169+ cells were present in the IT region of GC. The density of CD204+ Mφs correlated with poor prognosis in HCC, and CD169+ Mφs were associated with good survival in both HCC and GC. Moreover, the combination of low numbers of CD204+ and high numbers of CD169+ Mφs was associated with improved OS in both GC and HCC. CONCLUSIONS: Mφs display tissue-specific distributions and distinct composition patterns in HCC and GC tissues. Our results suggested that different types of tumors might use diverse strategies to reconstitute Mφ patterns to promote tumor progression.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Macrófagos/patologia , Neoplasias Gástricas/diagnóstico , Adolescente , Adulto , Idoso , Antígenos CD/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Neoplasias Gástricas/patologia , Análise de Sobrevida , Adulto Jovem
11.
Asian Pac J Cancer Prev ; 16(12): 5089-94, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26163647

RESUMO

FADS1 (fatty acid desaturase 1) plays a crucial role in fatty acid metabolism, and it was recently reported to be involved in tumorigenesis. However, the role of FADS1 expression in esophageal squamous cell carcinoma (ESCC) remains unknown. In the current study, we investigated the expression and clinical pathologic and prognostic significance of FADS1 in ESCC. Immunohistochemical analyses revealed that 58.2% (146/251) of the ESCC tissues had low levels of FADS1 expression, whereas 41.8% (105/251) exhibited high levels of FADS1 expression. In positive cases, FADS1 expression was detected in the cytoplasm of cells. Correlation analyses demonstrated that FADS1 expression was significantly correlated with tumor location (p=0.025) but not with age, gender, histological grade, tumor status, nodal status or TNM staging. Furthermore, patients with tumors expressing high levels of FADS1had a longer disease-free survival time (p<0.001) and overall survival time (p<0.001). Univariate and multivariate analyses revealed that, along with nodal status, FADS1 expression was an independent and significant predictive factor (p<0.001). In conclusion, our study suggested that FADS1 might be a valuable biomarker and potential therapeutic target for ESCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Ácidos Graxos Dessaturases/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Dessaturase de Ácido Graxo Delta-5 , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidade , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
12.
Med Oncol ; 31(8): 103, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25005846

RESUMO

Sirtuin-3 (SIRT3) protein is a member of Sirtuins family. It functions as a critical mitochondrial deacetylase, which is involved in a variety of diseases, such as cancer, cardiovascular disease and diabetes. However, its role in esophageal squamous cell carcinoma (ESCC) has never been investigated before. With the help of immunohistochemistry, we studied the clinical significance of SIRT3 expression in ESCC. The receiver operating characteristic method was used to define the SIRT3 IRS cutoff value. The correlations between SIRT3 expression and clinicopathological variables were assessed using Pearson's χ (2) test. To evaluate the clinical significance of SIRT3 expression, Kaplan-Meier analysis was used to compare postoperative survival between different SIRT3 expression groups of ESCC patients. High expression of SIRT3 in ESCC tissues was more frequently observed than corresponding adjacent non-malignant esophageal mucosa tissues. No correlations were found between SIRT3 expression and clinical parameters. Multivariate analysis revealed that SIRT3 expression was an independent prognostic factor in ESCC (HR 1.454, P = 0.034). Increased SIRT3 expression suggests unfavorable prognosis for ESCC patients. Further studies are warranted.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidade , Sirtuína 3/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico
14.
Infect Immun ; 73(11): 7535-40, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16239556

RESUMO

Bacillus anthracis is a spore-forming, gram-positive organism that is the causative agent of the disease anthrax. Recognition of Bacillus anthracis by the host innate immune system likely plays a key protective role following infection. In the present study, we examined the role of TLR2, TLR4, and MyD88 in the response to B. anthracis. Heat-killed Bacillus anthracis stimulated TLR2, but not TLR4, signaling in HEK293 cells and stimulated tumor necrosis factor alpha (TNF-alpha) production in C3H/HeN, C3H/HeJ, and C57BL/6J bone marrow-derived macrophages. The ability of heat-killed B. anthracis to induce a TNF-alpha response was preserved in TLR2-/- but not in MyD88-/- macrophages. In vivo studies revealed that TLR2-/- mice and TLR4-deficient mice were resistant to challenge with aerosolized Sterne strain spores but MyD88-/- mice were as susceptible as A/J mice. We conclude that, although recognition of B. anthracis occurs via TLR2, additional MyD88-dependent pathways contribute to the host innate immune response to anthrax infection.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antígenos de Diferenciação/metabolismo , Bacillus anthracis/imunologia , Receptores Imunológicos/metabolismo , Transdução de Sinais , Esporos Bacterianos/imunologia , Receptor 2 Toll-Like/fisiologia , Receptor 4 Toll-Like/fisiologia , Aerossóis , Animais , Linhagem Celular , Humanos , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo
15.
J Immunol ; 175(6): 3964-70, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16148144

RESUMO

In this report we provide evidence, for the first time, that bacterial DNA in the context of heat-killed Brucella abortus (HKBA) engages TLR9 in dendritic cells (DC), resulting in a Th1-like cytokine response. This is based on the findings that HKBA induction of IL-12p40 is: 1) abolished in DC from TLR9(-/-) mice; 2) blocked by suppressive oligodeoxynucleotides; 3) simulated by bacterial DNA derived from HKBA; and 4) abrogated by DNase or methylation of the DNA from HKBA. Furthermore, the effect of HKBA can be inhibited by chloroquine, indicating that endosomal acidification is required and supporting the notion that DNA from HKBA is interacting with TLR9 at the level of the endosome, as is the case with CpG oligodeoxynucleotides. In addition to DC, HKBA can elicit IL-12p40 secretion from macrophages, in which case the effect is wholly MyD88 dependent but only partially TLR9 dependent. This probably explains why HKBA effects in vivo are only partially reduced in TLR9(-/-), but absent in MyD88(-/-) mice. Because of their intimate interactions with T cells, the DC response is most likely to be critical for linking innate and adaptive immune responses, whereas the macrophage reaction may play a role in enhancing NK cell and bystander immune responses. In addition to IL-12p40, HKBA induces other Th1-like cytokines, namely, IFN-alpha and IFN-gamma, in a TLR9-dependent manner. These cytokines are important in protection against viruses and bacteria, and their induction enhances HKBA as a potential carrier for vaccines.


Assuntos
Brucella abortus/imunologia , Citocinas/biossíntese , DNA Bacteriano/farmacologia , Células Th1/imunologia , Receptor Toll-Like 9/metabolismo , Animais , Brucella abortus/genética , DNA Bacteriano/metabolismo , Células Dendríticas/química , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Endossomos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Temperatura Alta , Interferon-alfa/biossíntese , Interferon gama/biossíntese , Interleucina-12/biossíntese , Subunidade p40 da Interleucina-12 , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Knockout , Subunidades Proteicas/biossíntese , Vacinas de Produtos Inativados
16.
J Immunol ; 171(3): 1441-6, 2003 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12874236

RESUMO

Cattle and humans are susceptible to infection with the Gram-negative intracellular bacterium Brucella abortus. Heat-killed B. abortus (HKBA) is a strong Th1 adjuvant and carrier. Previously, we have demonstrated that dendritic cells produce IL-12 in response to HKBA stimulation. In the present study, we use knockout mice and in vitro reconstitution assays to examine the contribution of signaling by Toll-like receptors (TLRs) and their immediate downstream signaling initiator, myeloid differentiation protein MyD88, in the activation following stimulation by HKBA. Our results show that HKBA-mediated induction of IL-12p40 and TNF is dependent on the adapter molecule MyD88. To identify the TLR involved in HKBA recognition, we examined HKBA responses in TLR2- and TLR4-deficient animals. TNF responses to HKBA were TLR4 independent; however, the response in TLR2-deficient mice was significantly delayed and reduced, although not completely abolished. Studies using Chinese hamster ovary/CD14 reporter cell lines stably transfected with either human TLR2 or human TLR4 confirmed the results seen with knockout mice, namely TLR2, but not TLR4, can mediate cellular activation by HKBA. In addition, human embryonic kidney 293 cells, which do not respond to HKBA, were made responsive by transfecting TLR2, but not TLR4 or TLR9. Taken together, our data demonstrate that MyD88-dependent pathways are crucial for activation by HKBA and that TLR2 plays a role in TNF, but not IL-12p40 pathways activated by this microbial product.


Assuntos
Antígenos de Diferenciação/fisiologia , Vacina contra Brucelose/imunologia , Brucella abortus/imunologia , Interleucina-12/biossíntese , Glicoproteínas de Membrana/fisiologia , Subunidades Proteicas/biossíntese , Receptores de Superfície Celular/fisiologia , Receptores Imunológicos/fisiologia , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antígenos de Diferenciação/genética , Vacina contra Brucelose/administração & dosagem , Células CHO , Linhagem Celular , Cricetinae , Temperatura Alta , Humanos , Injeções Intraperitoneais , Interleucina-12/metabolismo , Subunidade p40 da Interleucina-12 , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide , NF-kappa B/metabolismo , Subunidades Proteicas/metabolismo , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Transdução de Sinais/genética , Receptor 2 Toll-Like , Receptor 4 Toll-Like , Receptor Toll-Like 9 , Receptores Toll-Like , Transfecção , Fator de Necrose Tumoral alfa/metabolismo
17.
Hum Gene Ther ; 13(2): 287-98, 2002 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-11812284

RESUMO

We have constructed a recombinant adeno-associated virus serotype 2 vector encoding human interleukin 10 (rAAVhIL10). IL-10 is a potent antiinflammatory/immune cytokine, which has received growing attention for its therapeutic potential. Human IL-10 (hIL-10) production was virus dose dependent after in vitro infection of HSG cells, a human submandibular gland cell line. The vector-derived hIL-10 produced was biologically active, as the medium from rAAVhIL10-infected HSG cells caused a dose-dependent blockade of IL-12 secretion from spleen cells of IL-10 knockout mice challenged with heat-killed Brucella abortus. Administration of rAAVhIL10 (10(10) genomes per gland) to both mouse submandibular glands led to hIL-10 secretion into the bloodstream (approximately 1-5 pg/ml), that is, in an endocrine manner, which was stable for approximately 2 months. Salivary gland administration of rAAVhIL10 under experimental conditions was more efficacious than intravenous administration (approximately 0.5-0.7 pg/ml). Also, hIL-10 was readily secreted in vitro from organ cultures of minced submandibular glands infected with rAAVhIL10, 6 or 8 weeks earlier. Consistent with these results, hIL-10 mRNA was detected by reverse transcription-polymerase chain reaction in submandibular glands of mice infected with rAAVhIL10 but not from control mice. At these doses, little to no hIL-10 was detected in mouse saliva. Using a rAAV serotype 2 vector encoding beta-galactosidase, we observed that the primary parenchymal target cells were ductal. These findings represent the first report of rAAV use to target exocrine glands for systemic secretion of a therapeutic protein, and support the notion that rAAV serotype 2 vectors may be useful in salivary glands for local (periglandular) and systemic gene-based protein therapeutics.


Assuntos
Dependovirus/genética , Técnicas de Transferência de Genes , Interleucina-10/metabolismo , Glândulas Salivares/metabolismo , Animais , Bacillus , Células COS , Linhagem Celular , Células Epiteliais/metabolismo , Humanos , Interleucina-10/sangue , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro , Recombinação Genética , Glândulas Salivares/citologia , Glândula Submandibular/metabolismo , Cauda
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