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1.
Diagnostics (Basel) ; 14(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38472940

RESUMO

Bladder cancer (BCa) is a significant health issue and poses a healthcare burden on patients, highlighting the importance of an effective detection method. Here, we developed a urine DNA methylation diagnostic panel for distinguishing between BCa and non-BCa. In the discovery stage, an analysis of the TCGA database was conducted to identify BCa-specific DNA hypermethylation markers. In the validation phase, DNA methylation levels of urine samples were measured with real-time quantitative methylation-specific PCR (qMSP). Comparative analysis of the methylation levels between BCa and non-BCa, along with the receiver operating characteristic (ROC) analyses with machine learning algorithms (logistic regression and decision tree methods) were conducted to develop practical diagnostic panels. The performance evaluation of the panel shows that the individual biomarkers of ZNF671, OTX1, and IRF8 achieved AUCs of 0.86, 0.82, and 0.81, respectively, while the combined yielded an AUC of 0.91. The diagnostic panel using the decision tree algorithm attained an accuracy, sensitivity, and specificity of 82.6%, 75.0%, and 90.9%, respectively. Our results show that the urine-based DNA methylation diagnostic panel provides a sensitive and specific method for detecting and stratifying BCa, showing promise as a standard test that could enhance the diagnosis and prognosis of BCa in clinical settings.

2.
Tzu Chi Med J ; 33(3): 224-232, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34386358

RESUMO

Neuroendocrine prostate cancer (NEPC) is the most lethal malignancy of prostate cancer (PCa). Treatment with next-generation androgen receptor (AR) pathway inhibitors (ARPIs) has successfully extended patients' lifespan. However, with the emergence of drug resistance, PCa tumors increasingly adapt to potent ARPI therapies by transitioning to alternative cellular lineage. Such therapy-induced drug resistance is largely driven from the cellular plasticity of PCa cells to alter their phenotypes of AR independence for cell growth and survival. Some of the resistant PCa cells undergo cellular reprogramming to form neuroendocrine phenotypes. Recent evidences suggest that this cellular reprogramming or the lineage plasticity is driven by dysregulation of the epigenome and transcriptional networks. Aberrant DNA methylation and altered expression of epigenetic modifiers, such as enhancer of zeste-homolog 2, transcription factors, histone demethylases, are hallmarks of NEPC. In this review, we discuss the nature of the epigenetic and transcriptional landscapes of PCa cells which lose their AR independence and transition to the neuroendocrine lineage. We also discuss how oncogenic signaling and metabolic reprogramming fuel epigenetic and transcriptional alterations. In addition, the current state of epigenetic therapies for NEPC is addressed.

3.
Theranostics ; 11(15): 7527-7545, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34158865

RESUMO

Rationale: One of the most common metabolic defects in cancers is the deficiency in arginine synthesis, which has been exploited therapeutically. Yet, challenges remain, and the mechanisms of arginine-starvation induced killing are largely unclear. Here, we sought to demonstrate the underlying mechanisms by which arginine starvation-induced cell death and to develop a dietary arginine-restriction xenograft model to study the in vivo effects. Methods: Multiple castration-resistant prostate cancer cell lines were treated with arginine starvation followed by comprehensive analysis of microarray, RNA-seq and ChIP-seq were to identify the molecular and epigenetic pathways affected by arginine starvation. Metabolomics and Seahorse Flux analyses were used to determine the metabolic profiles. A dietary arginine-restriction xenograft mouse model was developed to assess the effects of arginine starvation on tumor growth and inflammatory responses. Results: We showed that arginine starvation coordinately and epigenetically suppressed gene expressions, including those involved in oxidative phosphorylation and DNA repair, resulting in DNA damage, chromatin-leakage and cGAS-STING activation, accompanied by the upregulation of type I interferon response. We further demonstrated that arginine starvation-caused depletion of α-ketoglutarate and inactivation of histone demethylases are the underlying causes of epigenetic silencing. Significantly, our dietary arginine-restriction model showed that arginine starvation suppressed prostate cancer growth in vivo, with evidence of enhanced interferon responses and recruitment of immune cells. Conclusions: Arginine-starvation induces tumor cell killing by metabolite depletion and epigenetic silencing of metabolic genes, leading to DNA damage and chromatin leakage. The resulting cGAS-STING activation may further enhance these killing effects.


Assuntos
Arginina/deficiência , Cromatina/metabolismo , Reparo do DNA , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Nucleotidiltransferases/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Cromatina/genética , Cromatina/patologia , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Nucleotidiltransferases/genética , Células PC-3 , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia
4.
Nat Commun ; 12(1): 2398, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893278

RESUMO

Arginine plays diverse roles in cellular physiology. As a semi-essential amino acid, arginine deprivation has been used to target cancers with arginine synthesis deficiency. Arginine-deprived cancer cells exhibit mitochondrial dysfunction, transcriptional reprogramming and eventual cell death. In this study, we show in prostate cancer cells that arginine acts as an epigenetic regulator to modulate histone acetylation, leading to global upregulation of nuclear-encoded oxidative phosphorylation (OXPHOS) genes. TEAD4 is retained in the nucleus by arginine, enhancing its recruitment to the promoter/enhancer regions of OXPHOS genes and mediating coordinated upregulation in a YAP1-independent but mTOR-dependent manner. Arginine also activates the expression of lysine acetyl-transferases and increases overall levels of acetylated histones and acetyl-CoA, facilitating TEAD4 recruitment. Silencing of TEAD4 suppresses OXPHOS functions and prostate cancer cell growth in vitro and in vivo. Given the strong correlation of TEAD4 expression and prostate carcinogenesis, targeting TEAD4 may be beneficially used to enhance arginine-deprivation therapy and prostate cancer therapy.


Assuntos
Arginina/farmacologia , Proteínas de Ligação a DNA/genética , Epigênese Genética/efeitos dos fármacos , Epigenômica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Musculares/genética , Fosforilação Oxidativa/efeitos dos fármacos , Neoplasias da Próstata/genética , Fatores de Transcrição/genética , Animais , Arginina/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Humanos , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Musculares/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/metabolismo
5.
AJR Am J Roentgenol ; 215(1): 15-24, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32348183

RESUMO

OBJECTIVE. The purpose of this study was to determine whether contrast medium volume and method of administration and baseline estimated glomerular filtration rate influence the efficacy of prophylactic hydration for prevention of acute kidney injury after contrast administration. MATERIALS AND METHODS. An online search of PubMed conducted on August 25, 2017, produced a total of 697 studies. After the reports were reviewed, nine were included in this study. The extracted data on all patients in these studies were separated into a group that received prophylactic hydration and a group that did not. The following three parameters were used for subgroup analysis: contrast medium volume, contrast administration method, and baseline estimated glomerular filtration rate. The t test was performed, and study-level odds ratios with 95% CIs and p values were calculated. Tests of heterogeneity were conducted. RESULTS. When the volume of contrast agent administered exceeded 100 mL, hydration was beneficial in the prevention of contrast-induced acute kidney injury (odds ratio, 0.546). If the volume was less than 100 mL, hydration had no efficacy in preventing contrast-induced acute kidney injury (odds ratio, 0.917). Administration route and baseline estimated glomerular filtration rate exerted no effect on the efficacy of prophylactic hydration. CONCLUSION. For patients who receive less than 100 mL of contrast medium, the prevalent practice for contrast-enhanced CT studies, prophylactic hydration may not be necessary, regardless of the estimated glomerular filtration rate or route of contrast administration. For patients undergoing procedures requiring administration of large volumes of contrast medium, however, hydration is recommended to prevent contrast-induced acute kidney injury.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Hidratação/métodos , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos
6.
Medicine (Baltimore) ; 99(8): e19123, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32080088

RESUMO

World Health Organization tumor classifications of the central nervous system differentiate glioblastoma multiforme (GBM) into wild-type (WT) and mutant isocitrate dehydrogenase (IDH) genotypes. This study proposes a noninvasive computer-aided diagnosis to interpret the status of IDH in glioblastomas from transformed magnetic resonance imaging patterns. The collected image database was composed of 32 WT and 7 mutant IDH cases. For each image, a ranklet transformation which changed the original pixel values into relative coefficients was 1st applied to reduce the effects of different scanning parameters and machines on the underlying patterns. Extracting various textural features from the transformed ranklet images and combining them in a logistic regression classifier allowed an IDH prediction. We achieved an accuracy of 90%, a sensitivity of 57%, and a specificity of 97%. Four of the selected textural features in the classifier (homogeneity, difference entropy, information measure of correlation, and inverse difference normalized) were significant (P < .05), and the other 2 were close to being significant (P = .06). The proposed computer-aided diagnosis system based on radiomic textural features from ranklet-transformed images using relative rankings of pixel values as intensity-invariant coefficients is a promising noninvasive solution to provide recommendations about the IDH status in GBM across different healthcare institutions.


Assuntos
Neoplasias Encefálicas/genética , Diagnóstico por Computador/métodos , Glioblastoma/genética , Isocitrato Desidrogenase/genética , Adulto , Idoso , Algoritmos , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Genótipo , Glioblastoma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Mutação , Valor Preditivo dos Testes , Período Pré-Operatório , Sensibilidade e Especificidade
7.
J Clin Neurosci ; 69: 276-279, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31447356

RESUMO

Leukoencephalopathy, cerebral calcifications, and cysts (LCC) is an extremely rare neurological disease, also known as Labrune syndrome. The disease more commonly affects children and young adults and the characteristic triple imaging findings are leukoencephalopathy, calcifications and multiple cysts, presenting with a variety of supra- and infratentorial symptoms but lacking for extra-neurological manifestations. Coats plus syndrome and cerebroretinal microangiopathy with calcifications and cysts (CRMCC) share similar neurological findings with LCC, but additionally involves other extra-neurological organs. Tumoral excision is usually required due to mass effect to the eloquent brain of multiple growing cysts or hemorrhages, but the outcome of surgery varies. Here we demonstrate an 8-year neuroimaging study of a rare adult-onset case of LCC with gradual headache, hemiparesis, hand tremors, unstable gait, and seizure attacks despite several times of tumoral excision. Neuroimaging revealed multiple microbleeds and microcalcification in the leukoencephalopathic areas, with increasing calcifications, recurrent previously excised cysts and new cyst formation in the longitudinal neuroimaging follow-ups within the eight years. We believe that LCC involves microangiopathy, which causes blood-brain barrier disruption, myelin serum collection and subsequent growing cysts and dystrophic calcification formation. We provide histopathological correlation in the illustration. Due to the underlying pathomechanism and long-term recurrence nature, patients with a combination of cysts and calcifications on CT scan should be follow up carefully and postoperative recurrence after years may occur.


Assuntos
Calcinose/diagnóstico por imagem , Calcinose/patologia , Cistos do Sistema Nervoso Central/diagnóstico por imagem , Cistos do Sistema Nervoso Central/patologia , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/patologia , Adulto , Progressão da Doença , Seguimentos , Humanos , Masculino , Neuroimagem
8.
J Bioinform Comput Biol ; 17(3): 1940006, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31288639

RESUMO

Prostate cancer (PCa) is the second leading cause of cancer death among men worldwide. About 70% of PCa patients were diagnosed at later stage, and metastasis has been observed. Additionally, the cure rate of PCa closely relies on the early diagnosis with biomarkers. The identification of biomarkers for diagnosis and prognosis is an urgent clinical issue for PCa. Here, we developed a novel scoring strategy, including cluster score (CS) and predicting score (PS), to identify 29 PCa genes (called PCa29) for early diagnostic biomarkers from two datasets in Gene Expression Omnibus. The result indicates that PCa29 can discriminate between normal and tumor tissues and are specific for prostate cancer. To validate PCa29, we found that 97% of PCa29 were consistently significant with these gene expressions in The Cancer Genome Atlas; furthermore, ∼ 70% of PCa29 are consensus to the protein expression in The Human Protein Atlas. Finally, we examined 10 genes in PCa29 on three PCa cell lines by real-time quantitative polymerase chain reaction. The experimental results show that the trend of the differential PCa29 expression is consistent with the analyzed results from our novel scoring method. We believe that our method is useful and PCa29 are potential biomarkers that provide the clues to develop targeting therapy for PCa.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Neoplasias da Próstata/genética , Autoantígenos/genética , Linhagem Celular Tumoral , Análise por Conglomerados , Bases de Dados Factuais , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/estatística & dados numéricos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Colágenos não Fibrilares/genética , Mapas de Interação de Proteínas/genética , Reprodutibilidade dos Testes , Colágeno Tipo XVII
9.
J Chin Med Assoc ; 82(4): 289-294, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30946208

RESUMO

BACKGROUND: The prevalence of obesity in patients with hemophilia (PWH) varies among different ethnicities, and its influence on joint bleeding and hemophilic arthropathy has not been studied in Taiwan population. We explored the prevalence and clinical correlates of obesity and the impact of body mass index (BMI) on annual joint bleeding rate (AJBR) and hemophilic arthropathy in PWH in Taiwan. METHODS: We retrospectively collected clinical information on 140 severe/40 moderate PWH from 2006 to 2014. The patients' median age was 31.5 years, ranged from 6 to 73 years. Their BMI, 6 index joints score by Pettersson scoring, AJBR, and other clinical data were analyzed. RESULTS: The prevalence of overweight and obesity by age group was 7.1% in PWH aged ≤10 years, and rapidly increased to 34.5% in PWH aged 11 to 18 years, 46.7% in PWH aged 18 to 29 years, 61.8% in PWH aged 30 to 39 years, 60.6% in PWH aged 40 to 49 years, and 48% in PWH aged ≥50 years, respectively. Two peak rates were 72.7% in PWH aged 35 to 44 years and 66.7% in PWH aged >65 years. Age, HCV infection, knee score, elbow score, and total 6 index joints scores were found to correlate positively with BMI. However, subtype and severity of hemophilia, ankle scores, HBV and HIV infection did not correlate with BMI. Finally, BMI was found to correlate positively with AJBR in both adult and pediatric PWH. CONCLUSION: The prevalence of overweight and obesity in adolescent and adult PWH was higher than those in the general male population in Taiwan, which rapidly increased with age to peak in PWH aged 35 to 44 years and >65 years. High index joint score, with the exception of ankle scores, positively correlated with high BMI. Further, BMI and obesity also had positive correlation with AJBR in PWH. To our knowledge, this is the first study examining these associations in PWH in Taiwan.


Assuntos
Hemofilia A/complicações , Hemorragia/epidemiologia , Artropatias/epidemiologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Adulto Jovem
10.
Commun Biol ; 2: 105, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30911680

RESUMO

PKM2 is a key metabolic enzyme central to glucose metabolism and energy expenditure. Multiple stimuli regulate PKM2's activity through allosteric modulation and post-translational modifications. Furthermore, PKM2 can partner with KDM8, an oncogenic demethylase and enter the nucleus to serve as a HIF1α co-activator. Yet, the mechanistic basis of the exon-10 region in allosteric regulation and nuclear translocation remains unclear. Here, we determined the crystal structures and kinetic coupling constants of exon-10 tumor-related mutants (H391Y and R399E), showing altered structural plasticity and reduced allostery. Immunoprecipitation analysis revealed increased interaction with KDM8 for H391Y, R399E, and G415R. We also found a higher degree of HIF1α-mediated transactivation activity, particularly in the presence of KDM8. Furthermore, overexpression of PKM2 mutants significantly elevated cell growth and migration. Together, PKM2 exon-10 mutations lead to structure-allostery alterations and increased nuclear functions mediated by KDM8 in breast cancer cells. Targeting the PKM2-KDM8 complex may provide a potential therapeutic intervention.


Assuntos
Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Éxons , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Hormônios Tireóideos/química , Hormônios Tireóideos/genética , Hormônios Tireóideos/metabolismo , Transporte Ativo do Núcleo Celular , Regulação Alostérica , Histona Desmetilases/química , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Imuno-Histoquímica , Modelos Moleculares , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Conformação Proteica , Proteínas de Ligação a Hormônio da Tireoide
11.
Oncogene ; 38(1): 17-32, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30072740

RESUMO

During the evolution into castration or therapy resistance, prostate cancer cells reprogram the androgen responses to cope with the diminishing level of androgens, and undergo metabolic adaption to the nutritionally deprived and hypoxia conditions. AR (androgen receptor) and PKM2 (pyruvate kinase M2) have key roles in these processes. We report in this study, KDM8/JMJD5, a histone lysine demethylase/dioxygnase, exhibits a novel property as a dual coactivator of AR and PKM2 and as such, it is a potent inducer of castration and therapy resistance. Previously, we showed that KDM8 is involved in the regulation of cell cycle and tumor metabolism in breast cancer cells. Its role in prostate cancer has not been explored. Here, we show that KDM8's oncogenic properties in prostate cancer come from its direct interaction (1) with AR to affect androgen response and (2) with PKM2 to regulate tumor metabolism. The interaction with AR leads to the elevated expression of androgen response genes in androgen-deprived conditions. They include ANCCA/ATAD2 and EZH2, which are directly targeted by KDM8 and involved in sustaining the survival of the cells under hormone-deprived conditions. Notably, in enzalutamide-resistant cells, the expressions of both KDM8 and EZH2 are further elevated, so are neuroendocrine markers. Consequently, EZH2 inhibitors or KDM8 knockdown both resensitize the cells toward enzalutamide. In the cytosol, KDM8 associates with PKM2, the gatekeeper of pyruvate flux and translocates PKM2 into the nucleus, where the KDM8/PKM2 complex serves as a coactivator of HIF-1α to upregulate glycolytic genes. Using shRNA knockdown, we validate KDM8's functions as a regulator for both androgen-responsive and metabolic genes. KDM8 thus presents itself as an ideal therapeutic target for metabolic adaptation and castration-resistance of prostate cancer cells.


Assuntos
Adenocarcinoma/metabolismo , Proteínas de Transporte/metabolismo , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/fisiologia , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/fisiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Hormônios Tireóideos/metabolismo , ATPases Associadas a Diversas Atividades Celulares/fisiologia , Transporte Ativo do Núcleo Celular , Adenocarcinoma/patologia , Animais , Benzamidas , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/fisiologia , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Proteína Potenciadora do Homólogo 2 de Zeste/biossíntese , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Técnicas de Silenciamento de Genes , Glicólise/genética , Xenoenxertos , Histona Desmetilases/biossíntese , Histona Desmetilases/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos Nus , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Feniltioidantoína/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/patologia , Mapeamento de Interação de Proteínas , RNA Interferente Pequeno/genética , Receptores Androgênicos/genética , Proteínas de Ligação a Hormônio da Tireoide
12.
Commun Biol ; 1: 178, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30393775

RESUMO

Defective arginine synthesis, due to the silencing of argininosuccinate synthase 1 (ASS1), is a common metabolic vulnerability in cancer, known as arginine auxotrophy. Understanding how arginine depletion kills arginine-auxotrophic cancer cells will facilitate the development of anti-cancer therapeutic strategies. Here we show that depletion of extracellular arginine in arginine-auxotrophic cancer cells causes mitochondrial distress and transcriptional reprogramming. Mechanistically, arginine starvation induces asparagine synthetase (ASNS), depleting these cancer cells of aspartate, and disrupting their malate-aspartate shuttle. Supplementation of aspartate, depletion of mitochondria, and knockdown of ASNS all protect the arginine-starved cells, establishing the causal effects of aspartate depletion and mitochondrial dysfunction on the arginine starvation-induced cell death. Furthermore, dietary arginine restriction reduced tumor growth in a xenograft model of ASS1-deficient breast cancer. Our data challenge the view that ASNS promotes homeostasis, arguing instead that ASNS-induced aspartate depletion promotes cytotoxicity, which can be exploited for anti-cancer therapies.

13.
Cell Microbiol ; 20(12): e12947, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30151951

RESUMO

Cholesterol-α-glucosyltransferase (CGT) encoded by the type 1 capsular polysaccharide biosynthesis protein J (capJ) gene of Helicobacter pylori converts cellular cholesterol into cholesteryl glucosides. H. pylori infection induces autophagy that may increase bacterial survival in epithelial cells. However, the role of H. pylori CGT that exploits lipid rafts in interfering with autophagy for bacterial survival in macrophages has not been investigated. Here, we show that wild-type H. pylori carrying CGT modulates cholesterol to trigger autophagy and restrain autophagosome fusion with lysosomes, permitting a significantly higher bacterial burden in macrophages than that in a capJ-knockout (∆CapJ) mutant. Knockdown of autophagy-related protein 12 impairs autophagosome maturation and decreases the survival of internalised H. pylori in macrophages. These results demonstrate that CGT plays a crucial role in the manipulation of the autophagy process to impair macrophage clearance of H. pylori.


Assuntos
Autofagia/fisiologia , Colesterol/metabolismo , Glucosiltransferases/metabolismo , Helicobacter pylori/metabolismo , Macrófagos/microbiologia , Animais , Autofagossomos/metabolismo , Proteína 12 Relacionada à Autofagia/genética , Proteína 12 Relacionada à Autofagia/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Inativação de Genes , Glucosiltransferases/genética , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/patogenicidade , Interações Hospedeiro-Patógeno/fisiologia , Lisossomos/metabolismo , Lisossomos/microbiologia , Microdomínios da Membrana/metabolismo , Camundongos
14.
J Microbiol Immunol Infect ; 49(5): 636-645, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25070282

RESUMO

BACKGROUND/PURPOSE: Helicobacter pylori colonizes the human stomach and contributes to chronic inflammation of the gastric mucosa. H. pylori persistence occurs because of insufficient eradication by phagocytic cells. A key factor of H. pylori, cholesterol-α-glucosyltransferase encoded by capJ that extracts host cholesterol and converts it to cholesteryl glucosides, is important to evade host immunity. Here, we examined whether phagocytic trafficking in macrophages was perturbed by capJ-carrying H. pylori. METHODS: J774A.1 cells were infected with H. pylori at a multiplicity of infection of 50. Live-cell imaging and confocal microscopic analysis were applied to monitor the phagocytic trafficking events. The viability of H. pylori inside macrophages was determined by using gentamicin colony-forming unit assay. The phagocytic routes were characterized by using trafficking-intervention compounds. RESULTS: Wild type (WT) H. pylori exhibited more delayed entry into macrophages and also arrested phagosome maturation more than did capJ knockout mutant. Pretreatment of genistein and LY294002 prior to H. pylori infection reduced the internalization of WT but not capJ-knockout H. pylori in macrophages. CONCLUSION: Cholesterol glucosylation by H. pylori interferes with phagosome trafficking via a lipid-raft and PI3K-dependent manner, which retards engulfment of bacteria for prolonged intracellular survival of H. pylori.


Assuntos
Colesterol/análogos & derivados , Colesterol/metabolismo , Glucosiltransferases/metabolismo , Helicobacter pylori/imunologia , Evasão da Resposta Imune/imunologia , Macrófagos/imunologia , Fagossomos/imunologia , Animais , Linhagem Celular , Glucosiltransferases/genética , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Microdomínios da Membrana/metabolismo , Camundongos , Microscopia Confocal , Fagocitose/imunologia , Fagossomos/microbiologia , Fosfatidilinositol 3-Quinases/metabolismo
15.
Thorax ; 70(7): 707-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25786802

RESUMO

A 19-year-old boy with shortness of breath and chest pain after strenuous exercise presented to emergency department . On physical examination, the neck and shoulders appeared to be swollen. There was crepitus on skin palpation. Chest X-ray disclosed diffuse subcutaneous emphysema and pneumomediastinum. CT showed additional finding of air in epidural space. The patient was discharged after 2 days of hospitalisation with conservative treatment uneventfully. Pneumorrhachis is usually caused by abrupt increase in intrathoracic pressure in instance of forceful vomiting, cough or asthma attack in an otherwise healthy young adult. It is usually accompanied with pneumomediastinum. The management of epidural pneumatosis should be tailored according to its primary cause. For most patients with pneumorrhachis associated to a spontaneous pneumomediastinum without neurological symptoms, this condition is generally self-limited. For epidural free air of large volume that causes neurological deficits, surgical laminectomy may be indicated.


Assuntos
Dor no Peito/diagnóstico por imagem , Enfisema Mediastínico/diagnóstico por imagem , Enfisema Subcutâneo/diagnóstico por imagem , Dor no Peito/etiologia , Humanos , Masculino , Enfisema Mediastínico/complicações , Pescoço/diagnóstico por imagem , Enfisema Subcutâneo/complicações , Tomografia Computadorizada por Raios X , Adulto Jovem
16.
Proc Natl Acad Sci U S A ; 111(1): 279-84, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24344305

RESUMO

JMJD5, a Jumonji C domain-containing dioxygenase, is important for embryonic development and cancer growth. Here, we show that JMJD5 is up-regulated by hypoxia and is crucial for hypoxia-induced cell proliferation. JMJD5 interacts directly with pyruvate kinase muscle isozyme (PKM)2 to modulate metabolic flux in cancer cells. The JMJD5-PKM2 interaction resides at the intersubunit interface region of PKM2, which hinders PKM2 tetramerization and blocks pyruvate kinase activity. This interaction also influences translocation of PKM2 into the nucleus and promotes hypoxia-inducible factor (HIF)-1α-mediated transactivation. JMJD5 knockdown inhibits the transcription of the PKM2-HIF-1α target genes involved in glucose metabolism, resulting in a reduction of glucose uptake and lactate secretion in cancer cells. JMJD5, along with PKM2 and HIF-1α, is recruited to the hypoxia response element site in the lactate dehydrogenase A and PKM2 loci and mediates the recruitment of the latter two proteins. Our data uncover a mechanism whereby PKM2 can be regulated by factor-binding-induced homo/heterooligomeric restructuring, paving the way to cell metabolic reprogram.


Assuntos
Proteínas de Transporte/metabolismo , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Histona Desmetilases/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas de Membrana/metabolismo , Hormônios Tireóideos/metabolismo , Transporte Ativo do Núcleo Celular , Sítio Alostérico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Feminino , Glicólise , Células HEK293 , Células HeLa , Humanos , Hipóxia , Isoenzimas/metabolismo , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5 , Ácido Láctico/metabolismo , Células MCF-7 , Neoplasias/metabolismo , Ligação Proteica , Estrutura Quaternária de Proteína , Ativação Transcricional , Proteínas de Ligação a Hormônio da Tireoide
17.
PLoS One ; 7(2): e32142, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22393385

RESUMO

Members of protein families often share conserved structural subsites for interaction with chemically similar moieties despite low sequence identity. We propose a core site-moiety map of multiple proteins (called CoreSiMMap) to discover inhibitors and mechanisms by profiling subsite-moiety interactions of immense screening compounds. The consensus anchor, the subsite-moiety interactions with statistical significance, of a CoreSiMMap can be regarded as a "hot spot" that represents the conserved binding environments involved in biological functions. Here, we derive the CoreSiMMap with six consensus anchors and identify six inhibitors (IC(50)<8.0 µM) of shikimate kinases (SKs) of Mycobacterium tuberculosis and Helicobacter pylori from the NCI database (236,962 compounds). Studies of site-directed mutagenesis and analogues reveal that these conserved interacting residues and moieties contribute to pocket-moiety interaction spots and biological functions. These results reveal that our multi-target screening strategy and the CoreSiMMap can increase the accuracy of screening in the identification of novel inhibitors and subsite-moiety environments for elucidating the binding mechanisms of targets.


Assuntos
Biologia Computacional/métodos , Algoritmos , Sítios de Ligação , Dicroísmo Circular , Bases de Dados de Proteínas , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Biblioteca Gênica , Helicobacter pylori/metabolismo , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Mutagênese Sítio-Dirigida , Mycobacterium tuberculosis/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Ligação Proteica , Reprodutibilidade dos Testes
18.
PLoS One ; 7(3): e33481, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22438938

RESUMO

Shikimate kinase (SK), which catalyzes the specific phosphorylation of the 3-hydroxyl group of shikimic acid in the presence of ATP, is the enzyme in the fifth step of the shikimate pathway for biosynthesis of aromatic amino acids. This pathway is present in bacteria, fungi, and plants but absent in mammals and therefore represents an attractive target pathway for the development of new antimicrobial agents, herbicides, and antiparasitic agents. Here we investigated the detailed structure-activity relationship of SK from Helicobacter pylori (HpSK). Site-directed mutagenesis and isothermal titration calorimetry studies revealed critical conserved residues (D33, F48, R57, R116, and R132) that interact with shikimate and are therefore involved in catalysis. Crystal structures of HpSK·SO(4), R57A, and HpSK•shikimate-3-phosphate • ADP show a characteristic three-layer architecture and a conformationally elastic region consisting of F48, R57, R116, and R132, occupied by shikimate. The structure of the inhibitor complex, E114A • 162535, was also determined, which revealed a dramatic shift in the elastic LID region and resulted in conformational locking into a distinctive form. These results reveal considerable insight into the active-site chemistry of SKs and a selective inhibitor-induced-fit mechanism.


Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Helicobacter pylori/enzimologia , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Calorimetria , Domínio Catalítico/genética , Sequência Conservada , Cristalografia por Raios X , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Genes Bacterianos , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/genética , Humanos , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Conformação Proteica , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Ácido Chiquímico/metabolismo , Eletricidade Estática
19.
World J Gastroenterol ; 18(1): 34-43, 2012 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-22228968

RESUMO

AIM: To determine the number of regulatory T cells (Tregs) in gastric mucosa of patients with gastritis, peptic ulcers and gastric cancer. METHODS: This study was a retrospective analysis of gastric antrum biopsy specimens from healthy controls (n = 22) and patients with gastritis (n = 30), peptic ulcer (n = 83), or gastric cancer (n = 32). Expression of CD4, CD25 and Foxp3 was determined by immunohistochemistry in three consecutive sections per sample. RESULTS: Compared with healthy controls, there was an increased number of CD25(+) and Foxp3(+) cells in patients with gastritis (P = 0.004 and P = 0.008), peptic ulcer (P < 0.001 and P < 0.001), and gastric cancer (P < 0.001 and P < 0.001). The ratio of CD25(+)/CD4(+) or Foxp3(+)/CD4(+) cells was also significantly higher in all disease groups (P < 0.001, respectively). The number of CD4(+), CD25(+), and Foxp3(+) cells, and the ratio of CD25(+)/CD4(+) and Foxp3(+)/CD4(+) cells, were associated with the histological grade of the specimens, including acute inflammation, chronic inflammation, lymphoid follicle number, and Helicobacter pylori infection. The number of CD4(+), CD25(+) and Foxp3(+) cells, and the ratio of CD25(+)/CD4(+) and Foxp3(+)/CD4(+) cells, were negatively associated with intestinal metaplasia among gastritis (P < 0.001, P < 0.001, P < 0.001, P = 0.002 and P = 0.002) and peptic ulcer groups (P = 0.013, P = 0.004, P < 0.001, P = 0.040 and P = 0.003). CONCLUSION: Tregs are positively associated with endoscopic findings of gastroduodenal diseases and histological grade but negatively associated with intestinal metaplasia in gastritis and peptic ulcer groups.


Assuntos
Adenocarcinoma/imunologia , Fatores de Transcrição Forkhead/imunologia , Gastrite/imunologia , Úlcera Péptica/imunologia , Neoplasias Gástricas/imunologia , Linfócitos T Reguladores/imunologia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD4/imunologia , Feminino , Mucosa Gástrica/imunologia , Mucosa Gástrica/patologia , Gastrite/patologia , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/patologia , Humanos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/patologia , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Linfócitos T Reguladores/citologia
20.
Mol Microbiol ; 83(1): 67-84, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22053852

RESUMO

Helicobacter pylori infection is an aetiological cause of gastric disorders worldwide. H. pylori has been shown to assimilate and convert host cholesterol into cholesteryl glucosides (CGs) by cholesterol-α-glucosyltransferase encoded by capJ. Here, we show that CapJ-deficient (ΔcapJ) H. pylori resulted in greatly reduced type IV secretion system (TFSS)-associated activities, including the hummingbird phenotype of AGS cells, IL-8 production, CagA translocation/phosphorylation and CagA-mediated signalling events. Complementation of the ΔcapJ mutation with wild type cagJ or by adding CGs-containing lysates or exogenous fluorophore-tagged CGs reversed the mutant phenotypes. We also show that the wild-type but not ΔcapJ H. pylori recruited raft-associated components to sites of bacterial attachment. Fluorescence recovery after photobleaching (FRAP) analysis of AGS cells treated with fluorescence-tagged cholesterol/CGs revealed that there was a higher proportion of CGs associated with immobile fractions. CGs-associated membranes were also more resistant to a cold detergent extraction. Thus, we propose that CGs synthesized by H. pylori around host-pathogen contact sites partition in detergent-resistant membranes (DRMs), alters lateral-phase segregation in membrane and reorganizes membrane architecture. These processes together promote the formation of a functional TFSS and H. pylori infection.


Assuntos
Sistemas de Secreção Bacterianos , Membrana Celular/microbiologia , Colesterol/análogos & derivados , Infecções por Helicobacter/microbiologia , Helicobacter pylori/metabolismo , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular Tumoral , Colesterol/metabolismo , Helicobacter pylori/genética , Humanos
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