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1.
Int J Biol Macromol ; 276(Pt 1): 133824, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39002906

RESUMO

Ovarian cancer, the deadliest gynecological malignancy, primarily treated with chemotherapy. However, systemic chemotherapy often leads to severe toxic side effects and chemoresistance. Drug-loaded aerogels have emerged as a promising method for drug delivery, as they can improve drug solubility and bioavailability, control drug release, and reduce drug distribution in non-targeted tissues, thereby minimizing side effects. In this research, chitosan oligosaccharide (COS)-loaded nanofibers composite chitosan (CS) aerogels (COS-NFs/CS) with a porous network structure were created using nanofiber recombination and freeze-drying techniques. The core layer of the aerogel has a COS loading rate of 60 %, enabling the COS-NFs/CS aerogel to significantly inhibit the migration and proliferation of ovarian cancer cells (resulting in a decrease in the survival rate of ovarian cancer cells to 33.70 % after 48 h). The coaxial fiber's unique shell-core structure and the aerogel's porous network structure enable the COS-NFs/CS aerogels to release COS steadily and slowly over 30 days, effectively reducing the initial burst release of COS. Additionally, the COS-NFs/CS aerogels exhibit good biocompatibility, degradability (only retaining 18.52 % of their weight after 6 weeks of implantation), and promote angiogenesis, thus promoting wound healing post-oophorectomy. In conclusion, COS-NFs/CS aerogels show great potential for application in the treatment of ovarian cancer.

2.
Clin Chim Acta ; 559: 119686, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663471

RESUMO

Colorectal cancer (CRC) is a leading cause of cancer-related deaths. Recent advancements in genomic technologies and analytical approaches have revolutionized CRC research, enabling precision medicine. This review highlights the integration of multi-omics, spatial omics, and artificial intelligence (AI) in advancing precision medicine for CRC. Multi-omics approaches have uncovered molecular mechanisms driving CRC progression, while spatial omics have provided insights into the spatial heterogeneity of gene expression in CRC tissues. AI techniques have been utilized to analyze complex datasets, identify new treatment targets, and enhance diagnosis and prognosis. Despite the tumor's heterogeneity and genetic and epigenetic complexity, the fusion of multi-omics, spatial omics, and AI shows the potential to overcome these challenges and advance precision medicine in CRC. The future lies in integrating these technologies to provide deeper insights and enable personalized therapies for CRC patients.


Assuntos
Inteligência Artificial , Neoplasias Colorretais , Genômica , Medicina de Precisão , Neoplasias Colorretais/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Humanos , Multiômica
3.
Mol Biol Rep ; 51(1): 350, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38401002

RESUMO

BACKGROUND: Peroxisomal membrane protein 4 (PXMP4), a member of the peroxisome membrane protein PXMP2/4 family, participates in the progression of several malignant cancers. Nevertheless, the effect of PXMP4 in the development of gastric cancer (GC) is still unknown. As a result, the focus of this investigation was to elucidate the potential mechanisms of PXMP4 in GC. METHODS AND RESULTS: Firstly, bioinformatics analysis results showed higher expression of PXMP4 in GC tissues. Secondly, clinical analysis of 57 patients with GC revealed correlations between PXMP4 expression and differentiation, depth of invasion, as well as TNM stage. Furthermore, individuals with elevated PXMP4 expression in GC exhibited an unfavorable prognosis. In vitro data showed the involvement of knockdown/overexpression of PXMP4 in the proliferation, invasion, and migration of GC cells, and triggering the epithelial-mesenchymal transition (EMT) of GC cells through the activation of the PI3K/AKT signaling pathway. LY294002, a PI3K/AKT inhibitor, inhibited the expression of PI3K/AKT-related proteins but did not affect the expression of PXMP4. CONCLUSIONS: These findings indicate that PXMP4 potentially functions as an upstream molecule in the PI3K/AKT pathway, governing the EMT process in GC.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias Gástricas , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Transdução de Sinais , Transição Epitelial-Mesenquimal/genética , Proteínas de Membrana/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica
4.
Carbohydr Polym ; 329: 121687, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286563

RESUMO

Millions of patients annually suffer life-threatening illnesses caused by bacterial infections of skin wounds. However, the treatment of wounds infected with bacteria is a thorny issue in clinical medicine, especially with drug-resistant bacteria infections. Therefore, there is an increasing interest in developing wound dressings that can efficiently fight against drug-resistant bacterial infections and promote wound healing. In this work, an anti-drug-resistant bacterial chitosan/cellulose nanofiber/tannic acid (CS/CNF/TA) hydrogel with excellent wound management ability was developed by electrospinning and fiber breakage-recombination. The hydrogel exhibited an outstanding antibacterial property exceeding 99.9 %, even for drug-resistant bacteria. This hydrogel could adhere to the tissue surface due to its abundant catechol groups, which avoided the shedding of hydrogel during the movement. Besides, it exhibited extraordinary hemostatic ability during the bleeding phase of the wound and then regulated the wound microenvironment by absorbing water and moisturizing. Moreover, the CS/CNF/TA also promoted the regrowth of vessels and follicles, accelerating the healing of infected wound tissue, with a healing rate exceeding 95 % within a 14-day timeframe. Therefore, the CS/CNF/TA hydrogel opens a new approach for the healing of drug-resistant bacterial infected wounds.


Assuntos
Infecções Bacterianas , Quitosana , Hemostáticos , Nanofibras , Polifenóis , Humanos , Hemostáticos/farmacologia , Taninos , Celulose/farmacologia , Hidrogéis/farmacologia , Bactérias , Antibacterianos/farmacologia
5.
Oncol Lett ; 19(6): 3931-3936, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32391101

RESUMO

This study aimed to investigate the effect of video-assisted thoracoscopic surgery (VATS) on pain stress indicators nitric oxide (NO), interleukin-1ß (IL-1ß) and IL-6 in the treatment of mediastinal tumor in children, so as to explore the clinical application value of this surgery. A retrospective analysis was performed on 82 children with mediastinal tumor undergoing operation in Children's Hospital Affiliated to Zhengzhou University from January 2012 to January 2016. Among them, 48 children undergoing VATS were enrolled as an observation group, and 34 children undergoing conventional thoracotomy were enrolled as a control group. Enzyme-linked immunosorbent assay (ELISA) was used to detect the preoperative and postoperative expression levels of NO, IL-1ß and IL-6. The intraoperative clinical data, postoperative pain degree and infection rate were observed and recorded in real time, and then compared between the two groups. Before operation (T0), there were no statistically significant differences between the two groups in serum NO, IL-1ß and IL-6 expression levels, which were lower in the observation group than those in the control group at 12 h (T1) and 24 h (T2) after operation (P<0.05). The visual analog scale (VAS) score in the observation group was lower than that in the control group at T1 (P<0.05). Compared with the control group, the largest blade opening, intraoperative blood loss, drainage duration and postoperative pain degree were significantly improved in the observation group. The postoperative infection rate was 4.17% in the observation group, significantly lower than 17.64% in the control group. VATS is effective for postoperative pain stress indicators and infection control in children with mediastinal tumor, which is therefore more suitable for children with the disease and has a higher clinical value.

6.
Exp Ther Med ; 15(5): 4498-4502, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29731834

RESUMO

The aim of the present study was to analyze risk factors of intestinal perforation following surgery for the treatment of congenital heart disease in infants and young children, and to summarize experiences of diagnosis and treatment. A total of 3,270 children, who underwent congenital heart disease surgery under extracorporeal circulation from January 2010 to July 2015, were retrospectively analyzed. Among these children, three (0.09%) developed postoperative intestinal perforation. Primary diseases were Tetralogy of Fallot (two cases) and ventricular septal defect combined with atrial septal defect (one case). The age range of the children was 6-11 months and the weight range was 7.3-8.6 kg. Furthermore, these children underwent radical surgery under general anesthesia and extracorporeal circulation in low temperatures. Abdominal symptoms appeared 4-10 days after surgery, and included poor appetite, abdominal distension, intermittent vomiting, high fever, refractory irritability, crying and shortness of breath. One case was confirmed by routine abdominal puncture and the remaining two were confirmed by the detection of free gas under the diaphragm, as revealed by abdominal X-ray. Following the diagnosis of intestinal perforation, emergency intestinal fistula surgery was performed. At 3-5 days post-surgery, the patients underwent treatment by fasting and intravenously administered parenteral nutrition. Diet was increased following recovery of bowel function. All patients recovered following active treatment and 3-4 months following hospital discharge, the fistula was successfully closed. In conclusion, a concerted effort should be made to identify intestinal perforation in infants and young children with postoperative congenital heart disease during emergency surgery. Early diagnosis and treatment may significantly improve prognosis and reduce mortality.

7.
Int Surg ; 100(3): 510-3, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25785336

RESUMO

Sewing needles, albeit rare in the case of penetrating cardiac injury, are highly lethal; especially in children, because the injury is difficult to diagnose and treat. We herein present the case of a 13-month-old girl who was injured by a sewing needle inserted in the myocardium; it is the first report of its kind from mainland China. The 13-month-old girl was referred to our hospital with a range of symptoms, including convulsions, diarrhea, and cough. Chest X-ray and echocardiogram revealed a needle located below the aortic valve, passing through the ventricular septum and aortic root. Surgical removal of the needle was performed under extracorporeal circulation. No hemorrhage or arrhythmia was seen, so the operation was ended, and the patient was discharged 8 days after the surgery. An early diagnosis and intervention proved to be lifesaving for this patient with a penetrating cardiac injury. We hope this case can provide a reference for the treatment of similar situations.


Assuntos
Migração de Corpo Estranho/cirurgia , Traumatismos Cardíacos/cirurgia , Agulhas/efeitos adversos , Ferimentos Penetrantes/cirurgia , China , Feminino , Migração de Corpo Estranho/diagnóstico , Traumatismos Cardíacos/diagnóstico , Ventrículos do Coração/lesões , Ventrículos do Coração/cirurgia , Humanos , Lactente , Ferimentos Penetrantes/diagnóstico
8.
Int Surg ; 2014 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-25496602

RESUMO

Abstract Introduction: Sewing needles, albeit a rare case of penetrating cardiac injury, are highly lethal, especially in children, because it is difficult to diagnose and treat. We herein present the case of a 13-month-old girl who was injured by a sewing needle inserted in the myocardium, which probably is the first report from mainland China.Case presentation: The 13-month-old girl was referred to our hospital with a range of symptoms, such as convulsions, diarrhea, and cough. Chest X-ray and echocardiogram revealed a needle located below the aortic valve, passing through the ventricular septum and aortic root. Surgical removal of the needle was performed under extracorporeal circulation. No hemorrhage or arrhythmia was seen, so the operation was ended, and the patient was discharged 8 days after the surgery. Conclusion: An early diagnosis and intervention proved to be life-saving for this penetrating cardiac injury. Hopefully, this case could provide a reference for the treatment of similar situations.

9.
J Immunol ; 189(4): 1835-42, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22802411

RESUMO

After a primary immune response, T cell memory occurs when a subset of Ag-specific T cells resists peripheral selection by acquiring resistance to TCR-induced death. Recent data have implicated Bcl-2 interacting mediator of death (Bim) as an essential mediator of the contraction phase of T cell immunity. In this article, we describe that stromal-derived factor-1α (SDF-1α) ligation of CXCR4 on activated T cells promotes two parallel processes that favor survival, phospho-inactivation of Foxo3A, as well as Bim extralong isoform (Bim(EL)) degradation, both in an Akt- and Erk-dependent manner. Activated primary CD4 T cells treated with SDF-1α therefore become resistant to the proapoptotic effects of TCR ligation or IL-2 deprivation and accumulate cells of a memory phenotype. Unlike SDF-1α, gp120 ligation of CXCR4 has the opposite effect because it causes p38-dependent Bim(EL) upregulation. However, when activated CD4 T cells are treated with both gp120 and SDF-1α, the SDF-1α-driven effects of Bim(EL) degradation and acquired resistance to TCR-induced death predominate. These results provide a novel causal link between SDF-1α-induced chemotaxis, degradation of Bim(EL), and the development of CD4 T cell memory.


Assuntos
Proteínas Reguladoras de Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Quimiocina CXCL12/imunologia , Memória Imunológica/imunologia , Proteínas de Membrana/imunologia , Proteínas Proto-Oncogênicas/imunologia , Apoptose/imunologia , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linfócitos T CD4-Positivos/metabolismo , Quimiocina CXCL12/metabolismo , Quimiotaxia de Leucócito/imunologia , Citometria de Fluxo , Humanos , Immunoblotting , Imunoprecipitação , Ativação Linfocitária/imunologia , Proteínas de Membrana/metabolismo , Isoformas de Proteínas , Proteínas Proto-Oncogênicas/metabolismo , Receptores CXCR4/imunologia , Receptores CXCR4/metabolismo , Transdução de Sinais/imunologia , Transfecção , Regulação para Cima
10.
Case Reports Immunol ; 2012: 919241, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-25954555

RESUMO

We present here a novel case of an atypical Omenn syndrome (OS) phenotype due to mutations in the ADA gene encoding adenosine deaminase. This case is noteworthy for a significant increase in circulating CD56(bright)CD16- cytokine-producing NK cells after treatment with steroids for skin rash.

11.
Hum Immunol ; 71(5): 505-11, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20156508

RESUMO

Mutations in the TNFRSF13B (TACI) gene have been reported to be associated with Common Variable ImmunoDeficiency (CVID). Of 48 patients evaluated within the immunodeficiency clinic, 39 had CVID, 6 had symptomatic IgA deficiency (IgAD) with or without IgG2 and IgG4 subclass deficiency, while 3 had unclassified immune dysregulatory disorders. In all 48 patients TACI genetic testing was performed, and monoallelic mutations were observed in 4 of the 39 CVID patients (10.26%), an incidence comparable to other studies. Of the 6 IgAD patients, 1 had a heterozygous TACI mutation (16.67%), while of the 3 unclassified patients, 1 had a monoallelic TACI mutation (33.3%), but his sibling who also had the same mutation had CVID. The A181E mutation is one of the statistically significant, among the known TACI gene mutations. Here, 5 of the 6 patients were found to have the A181E mutation (10.42%), which is higher than previously observed. We also evaluated 114 controls and found the A181E mutation in only 1 individual (0.88%). We report in this study that the A181E mutation is associated with a very heterogeneous clinical presentation along with variability in B-cell numbers and amount of TACI protein on memory B cells.


Assuntos
Imunodeficiência de Variável Comum/genética , Proteína Transmembrana Ativadora e Interagente do CAML/genética , Linfócitos B/imunologia , Sequência de Bases , Separação Celular , Imunodeficiência de Variável Comum/imunologia , Imunodeficiência de Variável Comum/fisiopatologia , Citometria de Fluxo , Predisposição Genética para Doença , Humanos , Immunoblotting , Imunofenotipagem , Dados de Sequência Molecular , Mutação , Fenótipo , Reação em Cadeia da Polimerase
12.
Kidney Int ; 74(10): 1294-309, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18974760

RESUMO

Acute urinary obstruction causes interstitial inflammation with leukocyte accumulation and the secretion of soluble mediators. Here we show that unilateral ureteral ligation caused a progressive increase in renal F4/80(+) and F4/80(-) dendritic cells, monocytes, neutrophils and T-cells 24-72 h following obstruction. Depletion of dendritic cells by clodronate pretreatment showed these cells to be the most potent source of tumor necrosis factor and other pro-inflammatory mediators in the obstructed kidney. F4/80(+) dendritic cells and T-cells co-localized in the cortico-medullary junction and cortex of the obstructed kidney. Cytokine secretion patterns and surface phenotypes of T-cells from obstructed kidneys were found to include interferon-gamma-secreting CD4(+) and CD8(+) memory T-cells as well as interleukin 17 (IL-17)-secreting CD4(+) memory T-cells. Depletion of the intra-renal dendritic cells prior to ligation did not numerically reduce T-cells in obstructed kidneys but attenuated interferon-gamma and IL-17-competent T-cells. Our study shows that intra-renal dendritic cells are a previously unidentified early source of proinflammatory mediators after acute urinary obstruction and play a specific role in recruitment and activation of effector-memory T-cells including IL-17-secreting CD4(+) T-cells.


Assuntos
Células Dendríticas/imunologia , Interleucina-17 , Nefropatias/imunologia , Linfócitos T/imunologia , Obstrução Ureteral/imunologia , Doença Aguda , Animais , Citocinas , Mediadores da Inflamação , Rim/imunologia , Camundongos , Camundongos Endogâmicos C57BL
13.
Zhonghua Yi Xue Za Zhi ; 87(24): 1701-3, 2007 Jun 26.
Artigo em Chinês | MEDLINE | ID: mdl-17825154

RESUMO

OBJECTIVE: To study the feasibility of interphase fluorescence in situ hybridization (FISH) in detection of chromosomal aneuploidy in touch preparations of lung carcinoma and its clinic significance. METHODS: We examined 46 touch preparations of lung carcinomas by FISH with DNA specific for chromosomes 7, 8, 9 and 12 to detect chromosomal aneuploidy. RESULTS: Aneuploidy, mainly featured in gains of chromosomes 7, 8 and 12 and loss of chromosome 9 were observed in all of the touch preparations of the 46 cases with lung cancer. The rates of chromosomal aneuploidy detected by FISH were 67.4% (31/46), 60.9% (28/46), 28.3% (13/46) and 56.5% (26/31) respectively. CONCLUSION: Interphase FISH is feasible in detecting aneuploidy in touch preparations of lung cancer. These alterations may be applied to early diagnosis and predicting prognosis of lung cancer.


Assuntos
Aneuploidia , Hibridização in Situ Fluorescente/métodos , Neoplasias Pulmonares/genética , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Cromossomos Humanos Par 12 , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 8 , Cromossomos Humanos Par 9 , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Estadiamento de Neoplasias , Reprodutibilidade dos Testes
14.
Arch Biochem Biophys ; 460(2): 218-26, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17367745

RESUMO

The immunological effects of vitamin D receptor (VDR) ligands include inhibition of dendritic cell (DC) maturation, suppression of T-helper type 1 (Th1) T-cell responses and facilitation of antigen-specific immune tolerance in vivo. While studying the molecular profile of DCs cultured in the presence of 1alpha,25(OH)D3 or synthetic D3 analogs we observed that expression of the NF-kappaB family member RelB, which plays an essential role in DC differentiation and maturation, is selectively suppressed by VDR ligands. Further in vitro and in vivo studies of VDR-mediated RelB suppression indicated that the mechanism for this effect involves direct binding of VDR/RXR alpha to a defined region of the relB promoter and assembly of a negative regulatory complex containing HDAC3, HDAC1, SMRT and, most likely, other factors. Interestingly, promoter engagement by VDR and HDAC3, but not the other identified components, is enhanced by addition of a VDR ligand and inhibited by a pro-maturational stimulus (LPS) that results in RelB upregulation. Promoter assays in a panel of cell lines suggest that the VDR ligand-dependent component of relB suppression may occur selectively in antigen presenting cells. Cell type-specific, ligand-enhanced negative transcriptional regulation represents a potentially novel paradigm for VDR-controlled genes. In this report we review the experimental data to support such a mechanism for relB regulation in DCs and present a model for the process.


Assuntos
Calcitriol/farmacologia , Células Dendríticas/metabolismo , Modelos Moleculares , Receptores de Calcitriol/metabolismo , Fator de Transcrição RelB/metabolismo , Transcrição Gênica/fisiologia , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem Celular , Células Dendríticas/citologia , Histona Desacetilase 1 , Histona Desacetilases/metabolismo , Humanos , Ligantes , Ligação Proteica/efeitos dos fármacos , Elementos de Resposta/fisiologia , Receptor X Retinoide alfa/metabolismo , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Vitaminas/metabolismo , Vitaminas/farmacologia
15.
Hum Mutat ; 27(8): 742-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16835864

RESUMO

The checkpoint kinase 2 (CHEK2, also known as CHK2) is a tumor suppressor that participates in the DNA damage-signaling pathway. It is phosphorylated and activated following DNA damage, resulting in cell cycle arrest and apoptosis. Previously, we reported germline CHEK2 mutations in patients with prostate cancer. In this study, we have identified two novel somatic CHEK2 mutations, c.349A > G (p.R117G) and c.967A > C (p.E321K), in prostate tumor specimens and investigated the functions of these mutants in vivo. We have shown that most of the germline CHEK2 mutations and one somatic mutation (p.R117G) within FHA domain have modestly reduced CHEK2 kinase activity in comparison with wild-type CHEK2 while the other somatic mutation (p.E321K) within the kinase domain of CHEK2 totally abolished CHEK2 kinase activity. Given that several clinical CHEK2 mutations reside in the Forkhead-associated (FHA) domain, we further generated a series of missense mutations within this domain and demonstrated the requirement of an intact FHA domain for the full activation of CHEK2. Taken together, these results provide evidence that both germline and somatic CHEK2 mutations identified in prostate cancer may contribute to the development of prostate cancer through the reduction of CHEK2 activation in response to DNA damage and/or oncogenic stress.


Assuntos
Mutação de Sentido Incorreto , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases/genética , Linhagem Celular , Quinase do Ponto de Checagem 2 , Dano ao DNA , Ativação Enzimática , Humanos , Masculino , Proteínas Serina-Treonina Quinases/química , Estrutura Terciária de Proteína/fisiologia
16.
J Bone Miner Res ; 21(6): 886-94, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16753019

RESUMO

UNLABELLED: We report here the first association between vitamin D-resistant rickets, alopecia, and type 1 diabetes in a child with compound heterozygous mutations in the VDR gene. Transfection studies suggest dissociated effects of VDR gene mutations on the regulation of genes involved in vitamin D metabolism and dendritic cell maturation. INTRODUCTION: Whereas vitamin D may play a role in the immune tolerance process, no patient has been reported to associate hereditary vitamin D-resistant rickets (HVDRR) and an autoimmune disease, and no attempt has been made to delineate the outcome of mutations of the vitamin D receptor (VDR) on the transcription of genes controlling immune tolerance. MATERIALS AND METHODS: The VDR gene was analyzed in a child with vitamin D-resistant rickets, total alopecia, and early childhood-onset type 1 diabetes. Patient's fibroblasts and COS-7 cells transfected with wildtype or mutant VDRs were studied for ligand-binding capacity, transactivation activity using two gene promoters [CYP-24, a classical 1,25(OH)2D3-responsive gene, and relB, a critical NF-kappaB component for regulation of dendritic cell differentiation], VDR-RXR heterodimers association to CYP 24 VDREs by gel mobility shift assays, and co-activator binding by Glutathione-S-transferase pull-down assays. RESULTS: Two novel compound heterozygous mutations (L263R and R391S) were identified in the VDR ligand-binding domain in this child. Both mutations significantly impaired VDR ligand-binding capacity but had dissociated effects on CYP-24 and RelB promoter responses to vitamin D. CYP 24 response binding to SRC-1 and RXR-heterodimer binding to CYP24 VDREs were abolished in L263R mutants but normal or partially altered in R391S mutants. In the opposite, RelB responses to vitamin D were close to normal in L263R mutants but abolished in R391S mutants. CONCLUSIONS: We report the first clinical association between HVDRR, total alopecia, and early childhood-onset type 1 diabetes. Mutations in the VDR ligand-binding domain may hamper the 1,25(OH)2D3-mediated relB responses, an effect that depends on the site of the VDR mutation and cannot be anticipated from VDR ligand-binding ability or CYP-24 response. Based on these results, we propose to survey the immune function in patients with HVDRR, including those with moderate features of rickets.


Assuntos
Calcitriol/farmacologia , Diabetes Mellitus Tipo 1/complicações , Fibroblastos/enzimologia , Hipofosfatemia Familiar/complicações , Receptores de Calcitriol/genética , Esteroide Hidroxilases/genética , Fator de Transcrição RelB/genética , Animais , Células Cultivadas , Pré-Escolar , Diabetes Mellitus Tipo 1/genética , Fibroblastos/efeitos dos fármacos , França , Amplificação de Genes , Genoma , Humanos , Hipofosfatemia Familiar/genética , Masculino , Mutação , Regiões Promotoras Genéticas/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Análise de Sequência de DNA , Vitamina D3 24-Hidroxilase , População Branca/genética
17.
Proc Natl Acad Sci U S A ; 102(44): 16007-12, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16239345

RESUMO

The NF-kappaB component RelB is essential for dendritic cell (DC) differentiation and maturation. The vitamin D receptor (VDR) is a nuclear receptor that mediates inhibition of DC maturation and transcriptional repression of relB after engagement of its ligand, 1alpha,25-dihydroxyvitamin D(3), or related analogs (D(3) analogs). Ligand-dependent relB suppression was abolished by a histone deacetylase (HDAC) inhibitor. Constitutive association of VDR with the relB promoter was demonstrated in DCs by chromatin immunoprecipitation. Promoter binding by VDR was enhanced by ligand and reduced by LPS. Association of HDAC3 and HDAC1 with the relB VDR-binding site was observed, but only HDAC3 was reciprocally modulated by D(3) analog and LPS. Overexpression of HDAC3 caused relB promoter suppression, increased sensitivity to D(3) analog, and resistance to LPS. Depletion of HDAC3 attenuated relB suppression by D(3) analog. In vivo, D(3) analog resulted in reduced RelB in DCs from VDR WT mice but not VDR knockout mice. Other NF-lation of RelB and c-Rel in control animals. We conclude that vitamin D-regulated relB transcription in DCs is controlled by chromatin remodeling by means of recruitment of complexes including HDAC3.


Assuntos
Células Dendríticas/metabolismo , Histona Desacetilases/fisiologia , Regiões Promotoras Genéticas , Receptores de Calcitriol/metabolismo , Fator de Transcrição RelB/genética , Animais , Sítios de Ligação , Colecalciferol/análogos & derivados , Colecalciferol/farmacologia , Montagem e Desmontagem da Cromatina , Regulação da Expressão Gênica/efeitos dos fármacos , Histona Desacetilases/efeitos dos fármacos , Histona Desacetilases/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Knockout , Receptores de Calcitriol/genética , Transcrição Gênica/efeitos dos fármacos
18.
Transpl Immunol ; 11(3-4): 323-33, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12967785

RESUMO

The mechanisms by which regulatory T-cell populations are generated in vivo are poorly understood. Nonetheless, the possibility of generating T-cells with regulatory capacity ex vivo using pharmacologic agents or modified antigen presenting cells has been raised by a number of recent studies. In this study, the effect of combined glucocorticoid and 1,25 dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) agonists on dendritic cell (DC)-stimulated, antigen-specific CD4(+ve) T-cells was investigated. Following multiple rounds of DC-mediated stimulation in the presence of dexamethasone and an analog of 1,25(OH)(2)D(3), the resulting T-cells were characterized by: (a) enhanced IL-10 secretion upon subsequent antigen exposure, (b) attenuated secretion of IL-2 and interferon gamma, (c) lack of induction of Th2 (IL-4-secreting) phenotype, (d) significant antigen-specific suppression of primary T-cell proliferation and (e) retention of the ability to survive and proliferate to antigen in vivo. These IL-10-secreting T-cells were termed 'steroid hormone-conditioned T-cells'. When a co-stimulation-deficient population of DCs was employed for the in vitro, steroid hormone-conditioned stimulations, two additional effects were observed: (a) a further skewing towards antigen-specific IL-10 production and (b) enhanced activation-induced up-regulation of the inhibitory receptor CTLA-4 (CD152). It was concluded that DC-mediated generation of antigen-specific T-cells in vitro can be modulated to promote an IL-10-secreting, regulatory T-cell population using glucocorticoid and 1,25(OH)(2)D(3) agonists. This T-cell phenotype can be further enhanced by the use of co-stimulation-deficient DCs.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Calcitriol/análogos & derivados , Células Dendríticas/imunologia , Glucocorticoides/farmacologia , Interleucina-10/biossíntese , Animais , Antígenos/imunologia , Células da Medula Óssea/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Calcitriol/farmacologia , Diferenciação Celular , Interleucina-10/imunologia , Camundongos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
19.
J Biol Chem ; 278(49): 49378-85, 2003 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-14507914

RESUMO

The nuclear factor-kappaB (NF-kappaB) protein RelB plays a unique role in dendritic cell (DC) function and, as such, is an important regulator of antigen presentation and immune regulation. In this study, inhibition of RelB expression in DCs exposed to an analog of the active form of vitamin D3 (1alpha,25-dihydroxyvitamin D3 (1alpha,25-(OH)2D3)) was observed and shown to be mediated by the vitamin D receptor (VDR). Potential vitamin D response elements were identified within promoter regions of human and mouse relB genes. In gel shift experiments, these motifs specifically bound VDR.retinoid X receptor-alpha complexes. Reporter assays confirmed that transcriptional activity of human and mouse relB promoters was inhibited by 1alpha,25-(OH)2D3 agonists in a DC-derived cell line. The inhibition was abolished by mutagenesis of the putative vitamin D response elements and was enhanced by overexpression of VDR. Mutagenesis of NF-kappaB response elements within the relB promoter did not affect the magnitude of 1alpha,25-(OH)2D3 analog-mediated inhibition, ruling out an indirect effect on NF-kappaB signaling. Glucocorticoid caused additional inhibition of relB promoter activity when combined with the 1alpha,25-(OH)2D3 analog. This effect was dependent on the integrity of the NF-kappaB response elements, suggesting separate regulatory mechanisms for the two steroid pathways on this promoter. We conclude that relB is a direct target for 1alpha,25-(OH)2D3-mediated negative transcriptional regulation via binding of VDR.retinoid X receptor-alpha to discrete DNA motifs. This mechanism has important implications for the inhibitory effect of 1alpha,25-(OH)2D3 on DC maturation and for the potential immunotherapeutic use of 1alpha,25-(OH)2D3 analogs alone or combined with other agents.


Assuntos
Calcitriol/farmacologia , Células Dendríticas/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Fatores de Transcrição/genética , Transcrição Gênica/efeitos dos fármacos , Animais , Sequência de Bases , Calcitriol/agonistas , Calcitriol/análogos & derivados , Primers do DNA , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/fisiologia , Receptores de Calcitriol/fisiologia , Fator de Transcrição RelB , Fatores de Transcrição/fisiologia
20.
Am J Hum Genet ; 72(2): 270-80, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12533788

RESUMO

The DNA-damage-signaling pathway has been implicated in all human cancers. However, the genetic defects and the mechanisms of this pathway in prostate carcinogenesis remain poorly understood. In this study, we analyzed CHEK2, the upstream regulator of p53 in the DNA-damage-signaling pathway, in several groups of patients with prostate cancer. A total of 28 (4.8%) germline CHEK2 mutations (16 of which were unique) were found among 578 patients. Additional screening for CHEK2 mutations in 149 families with familial prostate cancer revealed 11 mutations (5 unique) in nine families. These mutations included two frameshift and three missense mutations. Importantly, 16 of 18 unique CHEK2 mutations identified in both sporadic and familial cases were not detected among 423 unaffected men, suggesting a pathological effect of CHEK2 mutations in prostate cancer development. Analyses of the two frameshift mutations in Epstein Barr virus-transformed cell lines, using reverse-transcriptase polymerase chain reaction and western blot analysis, revealed abnormal splicing for one mutation and dramatic reduction of CHEK2 protein levels in both cases. Overall, our data suggest that mutations in CHEK2 may contribute to prostate cancer risk and that the DNA-damage-signaling pathway may play an important role in the development of prostate cancer.


Assuntos
Mutação , Neoplasias da Próstata/genética , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases , Idade de Início , Idoso , Linhagem Celular Transformada , Quinase do Ponto de Checagem 2 , DNA de Neoplasias/análise , Mutação da Fase de Leitura , Expressão Gênica , Genes Reguladores , Genes p53 , Testes Genéticos , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Neoplasias da Próstata/epidemiologia , Fatores de Risco
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