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1.
Front Neurol ; 13: 1017086, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277911

RESUMO

Human papillomavirus (HPV) infection is a sexually transmitted disease that may lead to cervical cancer. HPV vaccines have been implemented widely to prevent this. While generally few complications of vaccination are reported, there have been occasional reports of adverse reactions post-vaccination. The safety profile of the HPV vaccine is reassuring. However, since its introduction, several serious post-vaccination central nervous system complications have been reported; however, causality has not been established. Herein, we describe a 39-year-old woman who developed seizures and experienced a rapid decline in memory shortly after her first dose of the HPV vaccine. Cranial magnetic resonance imaging and cerebrospinal fluid analysis were performed, and the patient was diagnosed with anti-glutamic acid decarboxylase 65 (anti-GAD65) antibody-associated autoimmune encephalitis. She responded well to high-dose glucocorticoids. Four-month follow-up revealed full recovery and absence of recurrence. Since the HPV vaccine is administered worldwide, this case should raise clinicians' awareness regarding the possible CNS complications related to vaccinations, such as anti-GAD65 antibody-associated AE.

2.
Adv Rheumatol ; 62: 5, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1360068

RESUMO

Abstract Objective: The objective was to evaluate whether initiation of urate-lowering treatment (ULT) during an acute gout flare prolonged the current episode. Methods: A comprehensive search of MEDLINE and Web of Science databases was conducted from their inception to 15 March 2021. Five randomized controlled trials (RCTs) with 381 patients met the inclusion criteria. Standardized mean difference (SMD), odds ratio (OR), and 95% confidence interval (CI) were used for estimating the clinical efficacy of ULT in acute gout. Results: There was no statistical difference in days to resolution (intent-to-treat analysis) (SMD, 0.68; 95% CI — 0.42 to 1.78; I2, 49%; p = 0.22), the pain visual analogue score (VAS) by day 10 (SMD, — 0.07; 95% CI — 0.30 to 0.16; I2, 0%; p = 0.53), C-reactive protein (CRP) from day 7 to 10 (SMD, — 1.14; 95% CI — 5.63 to 3.36; I2, 55%; p = 0.62), erythrocyte sedimentation rate (ESR) from day 7 to 10 (SMD, — 2.51; 95% CI — 5.46 to 0.45; I2, 0%; p = 0.10) and the recurrence of gout flares within 28-30 days (OR 0.78; 95% CI 0.29 to 2.09; I2, 0%; p = 0.62). Conclusion: Initiation of ULT during an acute gout flare did not prolong the duration of the flare. However, larger sample size studies are needed to confirm this finding. Trial registration number PROSPERO (CRD42021234581).

3.
Artigo em Inglês | MEDLINE | ID: mdl-32419822

RESUMO

Gout has become a public health problem that seriously threatens human health. Traditional Chinese medicines (TCMs) have a long history of treating gout and have some advantages compared with the conventional medicines. Compound TCM Tongfengtai granules are gradually being used for clinical treatment of gout, but its mechanism is still unclear. The purpose of this study was to explore the metabolic profiling of serum from gout patients before and after treatment with Tongfengtai granules and identify the differential metabolites and related metabolic pathways. A total of 40 gout patients hospitalized in Shenzhen Traditional Chinese Medicine Hospital from 2018 to March 2019 were recruited in the current study, and serum samples from these patients before and after treatment with Tongfengtai granules were collected. Gas chromatography-mass spectrometry (GC-MS) assay was used to identify serum metabolites. The OPLS-DA VIP method was used to screen for potential metabolic biomarkers, and MetaboAnalyst 4.0 was used to identify related metabolic pathways. The result showed that there was a significant difference in the concentrations of six metabolites in the serum after treatment: D-galactose, lactic acid, 3-hydroxybutyric acid, D-pyran (type) glucose, alanine, and L-isoleucine. Except D-pyran (type) glucose, the serum concentrations of the other five metabolites were all significantly reduced. Besides, pathway enrichment analysis found that these potential metabolic biomarkers were mainly involved in lactose degradation and the glucose-alanine cycle. Thus, the serum metabolic profiling of gout patients treated with Tongfengtai granules changed, and the differential metabolites and related metabolic pathways might provide clues for understanding the mechanism of Tongfengtai granules.

4.
Clin Rheumatol ; 38(8): 2189-2193, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31030362

RESUMO

Anti-small ubiquitin-like modifier-1 activating enzyme (anti-SAE) antibodies have been recently discovered especially for myosin and identified as dermatomyositis (DM) marker. The frequency of anti-SAE antibodies in DM patients is extremely low. Diffuse pruritic erythema may be one kind of clinical manifestations of DM with anti-SAE antibodies. In this report, a 48-year-old female patient with amyopathic dermatomyositis (ADM) carrying anti-SAE antibodies presented diffuse pruritic erythema for 5 months. Diffuse pruritic erythema improved after treatment with prednisolone, cyclosporine, and thalidomide. The clinical characteristics of 75 previously reported cases with anti-SAE antibody-positive DM were reviewed, and the manifestations of the Asian and Western cohorts were compared. It was revealed that the Asian patients were more susceptible to diffuse erythema (17/34 vs. 3/41, P = 0.000), dysphagia (16/34 vs. 10/41, P = 0.040), and interstitial lung disease (ILD) (21/34 vs. 5/41, P = 0.000) compared with the Western patients. The frequency of malignancy in the Asian cohort was significantly higher than that in the Western cohort (10/34 vs. 4/41, P = 0.030).


Assuntos
Dermatomiosite/complicações , Eritema/complicações , Prurido/complicações , Enzimas Ativadoras de Ubiquitina/imunologia , Anticorpos/imunologia , Povo Asiático , Ciclosporina/administração & dosagem , Dermatomiosite/etnologia , Eritema/etnologia , Feminino , Humanos , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Prednisolona/administração & dosagem , Prurido/etnologia , Talidomida/administração & dosagem , Resultado do Tratamento
5.
Int Immunopharmacol ; 55: 174-182, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29268189

RESUMO

In rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLSs) play an essential role in cartilage destruction. Aggressive migration and invasion by FLSs significantly affect RA pathology. Kaempferol has been shown to inhibit cancer cell migration and invasion. However, the effects of kaempferol on RA FLSs have not been investigated. Our study aimed to determine the effects of kaempferol on RA both in vitro and in vivo. In vitro, cell migration and invasion were measured using scratch assays and the Boyden chamber method, respectively. The cytoskeletal reorganization of RA FLSs was evaluated by immunofluorescence staining. Matrix metalloproteinase (MMP) levels were measured by real-time PCR, and protein expression levels were measured by western blotting. In vivo, the effects of kaempferol were evaluated in mice with CIA. The results showed that kaempferol reduced migration, invasion and MMP expression in RA FLSs. In addition, we demonstrated that kaempferol inhibited reorganization of the actin cytoskeleton during cell migration. Moreover, kaempferol dramatically suppressed tumor necrosis factor (TNF)-α-induced MAPK activation without affecting the expression of TNF-α receptors. We also demonstrated that kaempferol attenuated the severity of arthritis in mice with CIA. Taken together, these results suggested that kaempferol inhibits the migration and invasion of FLSs in RA by blocking MAPK pathway activation without affecting the expression of TNF-α receptors.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Fibroblastos/fisiologia , Quempferóis/uso terapêutico , Sinoviócitos/fisiologia , Actinas/metabolismo , Adulto , Idoso , Animais , Artrite Experimental , Movimento Celular , Células Cultivadas , Citoesqueleto/metabolismo , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos DBA , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/metabolismo
6.
Rheumatology (Oxford) ; 56(8): 1417-1427, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28431044

RESUMO

Objective: To explore the role of leonurine in the regulation of synovial inflammation and joint destruction inRA. Methods: Fibroblast-like synoviocytes were isolated from synovial tissue from RA patients. Pro-inflammatory cytokine and MMP expression was evaluated using real-time PCR and a cytometric bead array. Cell migration and invasion in vitro were measured using the Boyden chamber method and the scratch assay, respectively. Protein expression was measured by western blotting. Nuclear factor kappa B (NF-κB) nuclear translocation was detected by immunofluorescence. The in vivo effect of leonurine was evaluated in mice with CIA. Results: Leonurine treatment significantly decreased the production of pro-inflammatory cytokines (IL-1ß, IL-6, IL-8 and TNFα) and MMPs (MMP-1 and MMP-3) and suppressed the migration and invasion of RA fibroblast-like synoviocytes. The molecular analysis revealed that leonurine impaired TNFα-induced NF-κB signalling by inhibiting the phosphorylation and degradation of inhibitor of NF-κB alpha (IκBα) and subsequently preventing the nuclear translocation of the NF-κB p65 subunit. Leonurine also inhibited the p38 and Jun N-terminal kinase mitogen-activated protein kinases signalling pathways without affecting ERK signalling. Intraperitoneal injection of leonurine reduced synovial inflammation, joint destruction and the serum IL-1ß, IL-6 and TNFα levels in mice with CIA. Conclusion: Our findings show that leonurine reduces synovial inflammation and joint destruction in RA through the NF-κB and mitogen-activated protein kinases pathways. Leonurine has potential as a therapeutic agent for RA.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Ácido Gálico/análogos & derivados , Adulto , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Citocinas/efeitos dos fármacos , Feminino , Fibroblastos/metabolismo , Ácido Gálico/farmacocinética , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Metaloproteinase 1 da Matriz/efeitos dos fármacos , Metaloproteinase 3 da Matriz/efeitos dos fármacos , Camundongos , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/efeitos dos fármacos , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/patologia , Fator de Transcrição RelA/efeitos dos fármacos
7.
Oncotarget ; 7(10): 10723-38, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-26918602

RESUMO

Zinc deficiency (ZD) increases the risk of esophageal squamous cell carcinoma (ESCC), and marginal ZD is prevalent in humans. In rats, marked-ZD (3 mg Zn/kg diet) induces a proliferative esophagus with a 5-microRNA signature (miR-31, -223, -21, -146b, -146a) and promotes ESCC. Here we report that moderate and mild-ZD (6 and 12 mg Zn/kg diet) also induced esophageal hyperplasia, albeit less pronounced than induced by marked-ZD, with a 2-microRNA signature (miR-31, -146a). On exposure to an environmental carcinogen, ~16% of moderate/mild-ZD rats developed ESCC, a cancer incidence significantly greater than for Zn-sufficient rats (0%) (P ≤ 0.05), but lower than marked-ZD rats (68%) (P < 0.001). Importantly, the high ESCC, marked-ZD esophagus had a 15-microRNA signature, resembling the human ESCC miRNAome, with miR-223, miR-21, and miR-31 as the top-up-regulated species. This signature discriminated it from the low ESCC, moderate/mild-ZD esophagus, with a 2-microRNA signature (miR-31, miR-223). Additionally, Fbxw7, Pdcd4, and Stk40 (tumor-suppressor targets of miR-223, -21, and -31) were downregulated in marked-ZD cohort. Bioinformatics analysis predicted functional relationships of the 3 tumor-suppressors with other cancer-related genes. Thus, microRNA dysregulation and ESCC progression depend on the extent of dietary Zn deficiency. Our findings suggest that even moderate ZD may promote esophageal cancer and dietary Zn has preventive properties against ESCC. Additionally, the deficiency-associated miR-223, miR-21, and miR-31 may be useful therapeutic targets in ESCC.


Assuntos
Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/genética , MicroRNAs/genética , Zinco/deficiência , Animais , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Humanos , Masculino , Camundongos , MicroRNAs/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley
8.
J Natl Cancer Inst ; 107(11)2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26286729

RESUMO

BACKGROUND: Overexpression of microRNA-31 (miR-31) is implicated in the pathogenesis of esophageal squamous cell carcinoma (ESCC), a deadly disease associated with dietary zinc deficiency. Using a rat model that recapitulates features of human ESCC, the mechanism whereby Zn regulates miR-31 expression to promote ESCC is examined. METHODS: To inhibit in vivo esophageal miR-31 overexpression in Zn-deficient rats (n = 12-20 per group), locked nucleic acid-modified anti-miR-31 oligonucleotides were administered over five weeks. miR-31 expression was determined by northern blotting, quantitative polymerase chain reaction, and in situ hybridization. Physiological miR-31 targets were identified by microarray analysis and verified by luciferase reporter assay. Cellular proliferation, apoptosis, and expression of inflammation genes were determined by immunoblotting, caspase assays, and immunohistochemistry. The miR-31 promoter in Zn-deficient esophagus was identified by ChIP-seq using an antibody for histone mark H3K4me3. Data were analyzed with t test and analysis of variance. All statistical tests were two-sided. RESULTS: In vivo, anti-miR-31 reduced miR-31 overexpression (P = .002) and suppressed the esophageal preneoplasia in Zn-deficient rats. At the same time, the miR-31 target Stk40 was derepressed, thereby inhibiting the STK40-NF-κΒ-controlled inflammatory pathway, with resultant decreased cellular proliferation and activated apoptosis (caspase 3/7 activities, fold change = 10.7, P = .005). This same connection between miR-31 overexpression and STK40/NF-κΒ expression was also documented in human ESCC cell lines. In Zn-deficient esophagus, the miR-31 promoter region and NF-κΒ binding site were activated. Zn replenishment restored the regulation of this genomic region and a normal esophageal phenotype. CONCLUSIONS: The data define the in vivo signaling pathway underlying interaction of Zn deficiency and miR-31 overexpression in esophageal neoplasia and provide a mechanistic rationale for miR-31 as a therapeutic target for ESCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , MicroRNAs/antagonistas & inibidores , Oligonucleotídeos/farmacologia , Transdução de Sinais , Animais , Apoptose , Northern Blotting , Carcinoma de Células Escamosas/genética , Proliferação de Células , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica , Inflamação , Masculino , Análise em Microsséries , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase/métodos , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/genética , Regulação para Cima , Zinco/deficiência
9.
Carcinogenesis ; 33(9): 1736-44, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22689922

RESUMO

Zinc deficiency (ZD) increases the risk of esophageal squamous cell carcinoma (ESCC). In a rat model, chronic ZD induces an inflammatory gene signature that fuels ESCC development. microRNAs regulate gene expression and are aberrantly expressed in cancers. Here we investigated whether chronic ZD (23 weeks) also induces a protumorigenic microRNA signature. Using the nanoString technology, we evaluated microRNA profiles in ZD esophagus and six additional tissues (skin, lung, pancreas, liver, prostate and peripheral blood mononuclear cells [PBMC]). ZD caused overexpression of inflammation genes and altered microRNA expression across all tissues analyzed, predictive of disease development. Importantly, the inflammatory ZD esophagus had a distinct microRNA signature resembling human ESCC or tongue SCC miRNAomes with miR-31 and miR-21 as the top-up-regulated species. Circulating miR-31 was also the top-up-regulated species in PBMCs. In ZD esophagus and tongue, oncogenic miR-31 and miR-21 overexpression was accompanied by down-regulation of their respective tumor-suppressor targets PPP2R2A and PDCD4. Importantly, esophageal miR-31 and miR-21 levels were directly associated with the appearance of ESCC in ZD rats, as compared with their cancer-free Zn-sufficient or Zn-replenished counterparts. In situ hybridization analysis in rat and human tongue SCCs localized miR-31 to tumor cells and miR-21 to stromal cells. In regressing tongue SCCs from Zn-supplemented rats, miR-31 and miR-21 expression was concomitantly reduced, establishing their responsiveness to Zn therapy. A search for putative microRNA targets revealed a bias toward genes in inflammatory pathways. Our finding that ZD causes miR-31 and miR-21 dysregulation associated with inflammation provides insight into mechanisms whereby ZD promotes ESCC.


Assuntos
Carcinoma de Células Escamosas/etiologia , Neoplasias Esofágicas/etiologia , MicroRNAs/fisiologia , Zinco/deficiência , Animais , Proteínas Reguladoras de Apoptose/genética , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Esôfago/metabolismo , Humanos , Masculino , MicroRNAs/análise , Proteínas de Ligação a RNA/genética , Ratos , Ratos Sprague-Dawley , Língua/metabolismo , Neoplasias da Língua/genética , Zinco/administração & dosagem
10.
Carcinogenesis ; 32(4): 554-60, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21245412

RESUMO

Dietary zinc (Zn) deficiency is implicated in the pathogenesis of human oral-esophageal cancers. In rats, Zn deficiency causes increased cell proliferation and cyclooxygenase-2 (COX-2) overexpression and enhances oral carcinogenesis by 4-nitroquinoline 1-oxide (NQO). Zn replenishment reverses all these effects. We questioned whether Zn has antitumor efficacy in a Zn-sufficient animal by investigating in Zn-sufficient rats (i) the efficacy of Zn supplementation on the progression of tongue squamous cell carcinogenesis induced by drinking water exposure to high (20-30 p.p.m.) and low (10 p.p.m.) doses of NQO and (ii) the modulating effects of Zn supplementation on biomarker expression in tongue lesions by immunohistochemistry. In rats exposed to high doses of NQO, Zn supplementation significantly reduced the incidence of papillomas from 100 to 64.7% (P=0.018) and invasive carcinomas from 93.8 to 52.9% (P=0.017). In rats exposed to low doses of NQO, where only minimally invasive carcinomas developed, Zn supplementation significantly reduced tumor multiplicity, incidence of tumors (1-2 mm), hyperplasia, dysplasia, papillomas and progression to carcinoma. Immunohistochemical analysis of carcinomas showed that Zn supplementation caused a shift to a less proliferative/aggressive cancer phenotype by reducing cell proliferation, stimulating apoptosis and decreasing expression of the key tumor markers cyclin D1, p53 and COX-2. Additionally, Zn supplementation significantly reduced cell proliferation in non-lesional tongue squamous epithelia, thereby suppressing tumor development. Together, the results demonstrate that Zn supplementation has chemopreventive efficacy against oral carcinogenesis in nutritionally complete animals. Our data suggest that Zn supplementation may be efficacious in the chemoprevention of human oral cancer.


Assuntos
4-Nitroquinolina-1-Óxido/toxicidade , Neoplasias da Língua/prevenção & controle , Zinco/administração & dosagem , Animais , Apoptose , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/prevenção & controle , Proliferação de Células , Suplementos Nutricionais , Masculino , Ratos , Ratos Sprague-Dawley , Neoplasias da Língua/induzido quimicamente , Neoplasias da Língua/patologia , Zinco/sangue
11.
Int J Cancer ; 129(2): 331-45, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20857495

RESUMO

Zinc (Zn)-deficiency (ZD) is implicated in the pathogenesis of human oral-esophageal cancers. Previously, we showed that in ZD mice genetic deletion of cyclooxygenase-2 (Cox-2) enhances N-nitrosomethylbenzylamine-induced forestomach carcinogenesis. By contrast, Cox-2 deletion offers protection in Zn-sufficient (ZS) mice. We hypothesize that ZD activates pathways insensitive to COX-2 inhibition, thereby promoting carcinogenesis. This hypothesis is tested in a Cox-2(-/-) mouse tongue cancer model that mimics pharmacologic blockade of COX-2 by firstly examining transcriptome profiles of forestomach mucosa from Cox-2(-/-) and wild-type mice on a ZD vs. ZS diet, and secondly investigating the roles of identified markers in mouse forestomach/tongue preneoplasia and carcinomas. In Cox-2(-/-) mice exposed to the tongue carcinogen 4-nitroquinoline 1-oxide, dietary ZD elicited tongue/esophagus/forestomach carcinomas that were prevented by ZS. The precancerous ZD:Cox-2(-/-) vs. ZS:Cox-2(-/-) forestomach had an inflammatory signature with upregulation of the proinflammation genes S100a8 and S100a9. Bioinformatics analysis revealed overrepresentation of inflammation processes comprising S100a8/a9 and an nuclear factor (NF)-κB network with connectivity to S100A8. Immunohistochemistry revealed co-overexpression of S100A8, its heterodimeric partner S100A9, the receptor for advanced glycation end-products (RAGE), NF-κB p65, and cyclin D1, in ZD:Cox-2(-/-) forestomach/tongue preneoplasia and carcinomas, evidence for the activation of a RAGE-S100A8/A9 inflammatory pathway. Accumulation of p53 in these carcinomas indicated activation of additional inflammatory pathways. Zn-replenishment in ZD:Cox-2(-/-) mice reversed the inflammation and inhibited carcinogenesis. Thus, ZD activates alternative inflammation-associated cancer pathways that fuel tumor progression and bypass the antitumor effect of Cox-2 ablation. These findings have important clinical implications, as combination cancer therapy that includes Zn may improve efficacy.


Assuntos
Calgranulina A/metabolismo , Ciclo-Oxigenase 2/deficiência , Neoplasias Gástricas/patologia , Neoplasias da Língua/patologia , Zinco/deficiência , 4-Nitroquinolina-1-Óxido , Animais , Carcinógenos , Ciclo-Oxigenase 2/genética , Dimetilnitrosamina/análogos & derivados , Modelos Animais de Doenças , Progressão da Doença , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/enzimologia , Neoplasias Esofágicas/patologia , Feminino , Deleção de Genes , Inflamação/enzimologia , Masculino , Camundongos , Camundongos Knockout , Neoplasias Gástricas/induzido quimicamente , Neoplasias Gástricas/enzimologia , Neoplasias da Língua/induzido quimicamente , Neoplasias da Língua/enzimologia
12.
Int J Cancer ; 122(5): 978-89, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17985342

RESUMO

Zinc deficiency in humans is associated with an increased risk of upper aerodigestive tract (UADT) cancer. In rodents, zinc deficiency predisposes to carcinogenesis by causing proliferation and alterations in gene expression. We examined whether in zinc-deficient rodents, targeted disruption of the cyclooxygenase (COX)-2 pathway by the COX-2 selective inhibitor celecoxib or by genetic deletion prevent UADT carcinogenesis. Tongue cancer prevention studies were conducted in zinc-deficient rats previously exposed to a tongue carcinogen by celecoxib treatment with or without zinc replenishment, or by zinc replenishment alone. The ability of genetic COX-2 deletion to protect against chemically-induced forestomach tumorigenesis was examined in mice on zinc-deficient versus zinc-sufficient diet. The expression of 3 predictive biomarkers COX-2, nuclear factor (NF)-kappa B p65 and leukotriene A(4) hydrolase (LTA(4)H) was examined by immunohistochemistry. In zinc-deficient rats, celecoxib without zinc replenishment reduced lingual tumor multiplicity but not progression to malignancy. Celecoxib with zinc replenishment or zinc replenishment alone significantly lowered lingual squamous cell carcinoma incidence, as well as tumor multiplicity. Celecoxib alone reduced overexpression of the 3 biomarkers in tumors slightly, compared with intervention with zinc replenishment. Instead of being protected, zinc-deficient COX-2 null mice developed significantly greater tumor multiplicity and forestomach carcinoma incidence than wild-type controls. Additionally, zinc-deficient COX-2-/- forestomachs displayed strong LTA(4)H immunostaining, indicating activation of an alternative pathway under zinc deficiency when the COX-2 pathway is blocked. Thus, targeting only the COX-2 pathway in zinc-deficient animals did not prevent UADT carcinogenesis. Our data suggest zinc supplementation should be more thoroughly explored in human prevention clinical trials for UADT cancer.


Assuntos
Carcinoma de Células Escamosas/prevenção & controle , Ciclo-Oxigenase 2/deficiência , Neoplasias de Cabeça e Pescoço/prevenção & controle , Zinco/deficiência , Animais , Carcinógenos/toxicidade , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/etiologia , Celecoxib , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/prevenção & controle , Neoplasias de Cabeça e Pescoço/induzido quimicamente , Neoplasias de Cabeça e Pescoço/etiologia , Imuno-Histoquímica , Leucotrieno A4/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Pirazóis/farmacologia , Ratos , Ratos Sprague-Dawley , Sulfonamidas/farmacologia , Neoplasias da Língua/induzido quimicamente , Neoplasias da Língua/prevenção & controle , Fator de Transcrição RelA/metabolismo
13.
Cancer Res ; 67(5): 2256-2264, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17332356

RESUMO

p300/cyclic AMP-responsive element binding protein-binding protein (CBP) are general coactivators for multiple transcription factors involved in various cellular processes. Several highly conserved domains of p300/CBP serve as interacting sites for transcription factors and regulatory proteins. Particularly, the intrinsic histone acetyltransferase (HAT) activity and transactivation domains (TAD) play essential roles for their coactivating function. Autoacetylation of p300/CBP is commonly observed in cell-free HAT assays and has been implicated in the regulation of their HAT activity. Here, we show that six lysine-rich regions in several highly conserved functional domains of p300 are targeted by p300HAT for acetylation in cell-free systems. We show that p300 is susceptible to acetylation in cultured tumor cells and that its acetylation status is affected by histone deacetylase inhibitor trichostatin A. We further show that either treatment with deacetylase inhibitors or coexpression of Gal4-p300HAT, which alone has no transactivation activity, stimulates the activity of the COOH-terminal TAD of p300 (p300C-TAD). We have defined the minimal p300C-TAD and show that it is sufficient to respond to deacetylase inhibitors and is a substrate for p300HAT. Finally, we show that acetylated p300 possesses enhanced ability to interact with p53. Taken together, our data suggest that acetylation regulates p300C-TAD and that acetylation of p300/CBP may contribute to the dynamic regulation of their complex formation with various interacting partners.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Histona Acetiltransferases/metabolismo , Inibidores de Histona Desacetilases , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação/efeitos dos fármacos , Sequência de Aminoácidos , Domínio Catalítico , Células Cultivadas , Células HeLa , Humanos , Ácidos Hidroxâmicos/farmacologia , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Fatores de Transcrição de p300-CBP/química
14.
J Biol Chem ; 281(19): 13612-13619, 2006 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-16543236

RESUMO

Hypoxia-inducible factors (HIFs) are heterodimeric transcription factors regulating the oxygen supply, glucose metabolism, and angiogenesis. HIF function requires the recruitment of p300/CREB-binding protein, two coactivators with histone acetyltransferase activity, by the C-terminal transactivation domain of HIF-alpha (HIF-alphaCAD). Histone deacetylase inhibitors (HDAIs) induce differentiation or apoptosis and repress tumor growth and angiogenesis, hence being explored intensively as anti-cancer agents. Using combined pharmacological, biochemical, and genetic approaches, here we show that HDAIs repress the transactivation potential of HIF-alphaCAD. This repression is independent of the function of tumor suppressors von Hippel-Lindau or p53 or the degradation of HIF-alpha. We also demonstrate the sufficiency of low concentrations of HDAIs in repression of HIF target genes in tumor cells. We further show that HDAIs induce hyperacetylation of p300 and repress the HIF-1alpha.p300 complex in vivo. In vitro acetylation analysis reveals that the p300CH1 region, but not HIF-alphaCAD, is susceptible to acetylation. Taken together, our data demonstrate that a deacetylase activity is indispensable for the transactivation potential of HIF-alphaCAD and support a model that acetylation regulates HIF function by targeting HIF-alpha.p300 complex, not by direct acetylating HIF-alpha. The demonstration that HDAIs repress both HIF-1alpha and HIF-2alpha transactivation potential independently of von Hippel-Lindau tumor suppressor and p53 function indicates that HDAIs may have biological effects in a broad range of tissues in addition to tumors.


Assuntos
Inibidores de Histona Desacetilases , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Ligação Proteica , Ativação Transcricional , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
15.
Carcinogenesis ; 27(7): 1489-96, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16543248

RESUMO

Upper aerodigestive tract (UADT) cancer, including oral and esophageal cancer, is an important cause of cancer deaths worldwide. Patients with UADT cancer are frequently zinc deficient (ZD) and show a loss of function of the pivotal tumor suppressor gene p53. The present study examined whether zinc deficiency in collaboration with p53 insufficiency (p53+/-) promotes lingual and esophageal tumorigenesis in mice exposed to low doses of the carcinogen 4-nitroquinoline 1-oxide. In wild-type mice, ZD significantly increased the incidence of lingual and esophageal tumors from 0% in zinc sufficient (ZS) ZS:p53+/+ mice to approximately 40%. On the p53+/- background, ZD:p53+/- mice had significantly greater tumor incidence and multiplicity than ZS:p53+/- and ZD:p53+/+ mice, with a high frequency of progression to malignancy. Sixty-nine and 31% of ZD:p53+/- lingual and esophageal tumors, respectively, were squamous cell carcinoma versus 19 and 0% of ZS:p53+/- tumors (tongue, P = 0.003; esophagus, P = 0.005). Immunohistochemical analysis revealed that the increased cellular proliferation observed in preneoplastic lingual and esophageal lesions, as well as invasive carcinomas, was accompanied by overexpression of cytokeratin 14, cyclooxygenase-2 and metallothionein. In summary, a new UADT cancer model is developed in ZD:p53+/- mouse that recapitulates aspects of the human cancer and provides opportunities to probe the genetic changes intrinsic to UADT carcinogenesis and to test strategies for prevention and reversal of this deadly cancer.


Assuntos
Neoplasias Esofágicas/patologia , Neoplasias da Língua/patologia , Proteína Supressora de Tumor p53/deficiência , Zinco/deficiência , 4-Nitroquinolina-1-Óxido/toxicidade , Animais , Biomarcadores Tumorais/análise , Carcinógenos/toxicidade , Ciclo-Oxigenase 2/biossíntese , Modelos Animais de Doenças , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/genética , Feminino , Expressão Gênica , Predisposição Genética para Doença , Imuno-Histoquímica , Queratina-14 , Queratinas/biossíntese , Masculino , Metalotioneína/biossíntese , Camundongos , Camundongos Mutantes , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Neoplasias da Língua/induzido quimicamente , Neoplasias da Língua/genética
16.
Cancer Res ; 65(17): 7790-9, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16140947

RESUMO

Zinc deficiency in rats enhances esophageal cell proliferation, causes alteration in gene expression, and promotes esophageal carcinogenesis. Zinc replenishment rapidly induces apoptosis in the esophageal epithelium thereby reversing cell proliferation and carcinogenesis. To identify zinc-responsive genes responsible for these divergent effects, we did oligonucleotide array-based gene expression profiling analyses in the precancerous zinc-deficient esophagus and in zinc-replenished esophagi after treatment with intragastric zinc compared with zinc-sufficient esophagi. Thirty-three genes (21 up-regulated and 12 down-regulated) showed a > or = 2-fold change in expression in the hyperplastic zinc-deficient versus zinc-sufficient esophageal epithelia. Expression of genes involved in cell division, survival, adhesion, and tumorigenesis were markedly changed. The zinc-sensitive gene metallothionein-1 (MT-1 was up-regulated 7-fold, the opposite of results for small intestine and liver under zinc-deficient conditions. Keratin 14 (KRT14, a biomarker in esophageal tumorigenesis), carbonic anhydrase II (CAII, a regulator of acid-base homeostasis), and cyclin B were up-regulated >4-fold. Immunohistochemistry showed that metallothionein and keratin 14 proteins were overexpressed in zinc-deficient esophagus, as well as in lingual and esophageal squamous cell carcinoma from carcinogen-treated rats, emphasizing their roles in carcinogenesis. Calponin 1 (CNN1, an actin cross-linking regulator) was down-regulated 0.2-fold. Within hours after oral zinc treatment, the abnormal expression of 29 of 33 genes returned to near zinc-sufficient levels, accompanied by reversal of the precancerous phenotype. Thus, we have identified new molecular markers in precancerous esophagus and showed their restoration by zinc replenishment, providing insights into the interaction between zinc and gene expression in esophageal cancer development and prevention.


Assuntos
Neoplasias Esofágicas/etiologia , Regulação Neoplásica da Expressão Gênica , Lesões Pré-Cancerosas/etiologia , Zinco/deficiência , 4-Nitroquinolina-1-Óxido/farmacologia , Animais , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Imuno-Histoquímica , Queratina-14 , Queratinas/biossíntese , Queratinas/genética , Masculino , Metalotioneína/biossíntese , Metalotioneína/genética , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima , Zinco/administração & dosagem
17.
J Natl Cancer Inst ; 97(1): 40-50, 2005 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-15632379

RESUMO

BACKGROUND: Cancer of the upper aerodigestive tract, including esophageal and tongue carcinomas, is a major cause of cancer deaths worldwide. Esophageal and tongue cancers have both been associated with dietary zinc deficiency (ZD), and cyclooxygenase (COX-2) is often overexpressed in these cancers. Using rat models, we examined whether zinc regulates COX-2 expression in these cancers. METHOD: Expression of COX-2 protein and mRNA in rat lingual and esophageal epithelia in control (zinc sufficient [ZS]) rats, during ZD, and after intragastric zinc replenishment (ZR) were determined by immunoblotting, immunohistochemistry, and real-time quantitative polymerase chain reaction. COX-2 gene expression, cell proliferation, and apoptosis were analyzed in ZD, ZR, and ZD rats treated with the COX-2 inhibitors celecoxib and indomethacin. Tumor development in ZD rats treated by continuous exposure to the carcinogen 4-nitroquinoline 1 oxide (NQO), which causes tongue tumors in rats, was compared with those in NQO-treated ZS rats. Statistical tests were two-sided. RESULTS: The esophagus and tongue of ZD rats were hyperplastic and expressed COX-2 protein and mRNA at 8- to 14.7-fold higher levels than control rats. Within hours ZR reduced COX-2 overexpression to threefold that in control rats and reversed the hyperplastic phenotypes. The esophagus of ZD rats treated with celecoxib or indomethacin showed a reduction in cell proliferation and stimulation of apoptosis. NQO treatment resulted in greater incidence of lingual squamous cell carcinomas (74% versus 22%, difference = 52%, 95% confidence interval [CI] = 20% to 80%, P = .015) and greater tumor multiplicity (13.1 versus 4.3, difference = 8.8, 95% CI = 7.0 to 10.6, P = .018) in ZD than ZS rats. Of 23 NQO-treated ZD rats, 39% (9) and 61% (14) harbored esophageal and forestomach tumors, respectively, whereas none of the NQO-treated ZS rats did. CONCLUSIONS: COX-2 overexpression accompanies hyperplasia in ZD rats. Increased cell proliferation in NQO-treated ZD rats facilitates the development of tumors at multiple sites. The finding that zinc regulates COX-2 expression in vivo in an animal model may lead to prevention or therapeutic possibilities for upper aerodigestive tract cancer.


Assuntos
Dieta , Neoplasias Esofágicas/enzimologia , Isoenzimas/efeitos dos fármacos , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/metabolismo , Neoplasias da Língua/enzimologia , Zinco/sangue , Zinco/farmacologia , 4-Nitroquinolina-1-Óxido , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Carcinógenos , Carcinoma de Células Escamosas/enzimologia , Celecoxib , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Modelos Animais de Doenças , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/prevenção & controle , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hiperplasia/induzido quimicamente , Hiperplasia/prevenção & controle , Indometacina/farmacologia , Isoenzimas/genética , Masculino , Mutagênicos , Prostaglandina-Endoperóxido Sintases/genética , Pirazóis/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sulfonamidas/farmacologia , Neoplasias da Língua/induzido quimicamente , Neoplasias da Língua/prevenção & controle , Regulação para Cima/efeitos dos fármacos , Zinco/administração & dosagem , Zinco/deficiência
18.
Cell Mol Neurobiol ; 23(4-5): 851-64, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14514036

RESUMO

1. Our previous studies demonstrated that when neural stem cells (NSCs) of the C17.2 clonal line are transplanted into the intact or 6-hydroxydopamine (6-OHDA) lesioned rat striatum, in most, but not all grafts, cells spontaneously express the dopamine (DA) biosynthetic enzymes, tyrosine hydroxylase (TH), and aromatic L-amino acid decarboxylase (Yang, M., Stull, N. D., Snyder. E. Y., Berk, M. A., and Iacovitti, L. (2002). Exp. Neurol.). 2. These results suggested that there were certain conditions which were more conducive to the development of DA traits in NSCs and possibly other neurotransmitter phenotypes. 3. In the present study, we modified a number of variables in vitro (i.e. passage number, confluence) and/or in vivo (degree, type, and site of injury) before assessing the survival, migration. and differentiation of engrafted NSCs. 4. We found that low confluence cultures were comprised exclusively of flattened polygonal cells, which when transplanted, migrated widely in the brain but did not express TH. 5. In contrast, high confluence cultures contained both polygonal cells and an overlying bed of fusiform cells. 6. When these NSCs were maintained for 12-20 passages and then transplanted, virtually all engrafted cells in 65% of the grafts expressed TH but not markers of other neurotransmitter systems. 7. Importantly, all TH+ grafts were accompanied by significant physical damage to the brain while TH- grafts were not, suggesting that local injury-related factors were also important. 8. Of no apparent influence on TH expression, regardless of how cells were grown prior to implantation, was the site of transplantation (cortex or striatum) or the degree of chemical lesion (intact, partial or full). 9. We conclude that transplanted NSCs can express traits specifically associated with DA neurons but only when cells are grown under certain conditions in vitro and then transplanted in proximity to injury-induced factors present in vivo.


Assuntos
Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Dopamina/biossíntese , Neurônios/fisiologia , Transplante de Células-Tronco/métodos , Células-Tronco/fisiologia , Animais , Biomarcadores , Comunicação Celular/fisiologia , Tamanho Celular/fisiologia , Células Cultivadas , Denervação , Sobrevivência de Enxerto/fisiologia , Camundongos , Neurônios/citologia , Oxidopamina , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Ratos , Células-Tronco/citologia , Substância Negra/citologia , Substância Negra/crescimento & desenvolvimento , Substância Negra/cirurgia , Tirosina 3-Mono-Oxigenase/metabolismo
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