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1.
J Addict Med ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408186

RESUMO

OBJECTIVES: To provide valuable insights for targeted cancer screening among high-risk patients, we analyzed the global and regional burden of neoplasms resulting from alcohol consumption between 1990 and 2019. METHODS: The information used in this study was collected from the Global Burden of Disease 2019 dataset. Initially, the database was used to extract details of mortality rates, disability-adjusted life years (DALYs), and the number of individuals affected by alcohol-related neoplasms (ARNs). Subsequently, the data were compared by cancer type, sex, age, region, and sociodemographic index. Furthermore, the study involved the calculation and comparison of estimated annual percentage changes in age-standardized DALYs rates (ASDRs) and mortality rates. RESULTS: The impact of alcohol on the burden of cancer varied by type of cancer, sex, age, and geographical location. Notably, males exhibited significantly higher ASDRs compared with females. Specifically, in 2019, alcohol emerged as the primary contributor to the number of DALYs associated with esophageal cancer, followed by liver cancer and colorectal cancer in men. Patients aged 50+ years exhibited a heightened rate of DALYs associated with ARNs. From 1990 to 2019, ASDRs among individuals with ARNs did not exhibit a decline in low-middle and low sociodemographic index regions. CONCLUSIONS: Alcohol consumption represents a significant risk factor for the burden of cancer, particularly within the realm of digestive system malignancies. Consequently, targeted cancer screening efforts should be directed toward the population that engages in alcohol drinking, with a particular focus on men aged 50 years and older, residing in economically disadvantaged areas.

2.
EMBO Mol Med ; 15(5): e15924, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36947051

RESUMO

The WD-repeat (WDR) family affects carcinogenesis, but its role in the immune microenvironment is poorly characterized. Although functional loss or gain of WDR6 does not markedly change in vitro proliferative and invasive capacity of HCC cells, its deficiency in hepa1-6 cells drastically inhibits the growth and lung metastasis of orthotopically implanted tumors in immune-competent C57BL/6J mice. Mechanistically, WDR6 targets tumor suppressor UVRAG to the CUL4A-DDB1-ROC1 E3 ubiquitin ligase complex through a unique WDxR motif and promotes its degradation. This upregulates chromatin accessibility at the TNFα locus by blocking autophagic degradation of p65, elevates intratumoral myeloid-derived suppressor cell (MDSC) number, and reduces CD8+ T cell infiltration, thereby promoting HCC progression. These immunosuppressive effects are reversed by TNFα blockade. TNFα recruits NF-κB to activate the transcription of WDR6, establishing a WDR6-TNFα loop. Clinically, the WDR6/UVRAG/NF-κB pathway is hyperactivated in HCC, predicting a poor prognosis. Importantly, a WDxR-like peptide disrupts the WDR6/UVRAG complex and enhances the efficiency of anti-PD-L1 against HCC with WDR6 dysregulation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Fator de Necrose Tumoral alfa , NF-kappa B , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Microambiente Tumoral , Linhagem Celular Tumoral
3.
Autophagy ; 17(3): 723-742, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32186433

RESUMO

Although the treatment of brain tumors by targeting kinase-regulated macroautophagy/autophagy, is under investigation, the precise mechanism underlying autophagy initiation and its significance in glioblastoma (GBM) remains to be defined. Here, we report that PAK1 (p21 [RAC1] activated kinase 1) is significantly upregulated and promotes GBM development. The Cancer Genome Atlas analysis suggests that the oncogenic role of PAK1 in GBM is mainly associated with autophagy. Subsequent experiments demonstrate that PAK1 indeed serves as a positive modulator for hypoxia-induced autophagy in GBM. Mechanistically, hypoxia induces ELP3-mediated PAK1 acetylation at K420, which suppresses the dimerization of PAK1 and enhances its activity, thereby leading to subsequent PAK1-mediated ATG5 (autophagy related 5) phosphorylation at the T101 residue. This event not only protects ATG5 from ubiquitination-dependent degradation but also increases the affinity between the ATG12-ATG5 complex and ATG16L1 (autophagy related 16 like 1). Consequently, ELP3-dependent PAK1 (K420) acetylation and PAK1-mediated ATG5 (T101) phosphorylation are required for hypoxia-induced autophagy and brain tumorigenesis by promoting autophagosome formation. Silencing PAK1 with shRNA or small molecule inhibitor FRAX597 potentially blocks autophagy and GBM growth. Furthermore, SIRT1-mediated PAK1-deacetylation at K420 hinders autophagy and GBM growth. Clinically, the levels of PAK1 (K420) acetylation significantly correlate with the expression of ATG5 (T101) phosphorylation in GBM patients. Together, this report uncovers that the acetylation modification and kinase activity of PAK1 plays an instrumental role in hypoxia-induced autophagy initiation and maintaining GBM growth. Therefore, PAK1 and its regulator in the autophagy pathway might represent potential therapeutic targets for GBM treatment.Abbreviations: 3-MA: 3-methyladenine; Ac-CoA: acetyl coenzyme A; ATG5: autophagy related 5; ATG16L1, autophagy related 16 like 1; BafA1: bafilomycin A1; CDC42: cell division cycle 42; CGGA: Chinese Glioma Genome Atlas; CHX, cycloheximide; ELP3: elongator acetyltransferase complex subunit 3; GBM, glioblastoma; HBSS: Hanks balanced salts solution; MAP1LC3B/LC3: microtubule associated protein 1 light chain 3 beta; MAP2K1: mitogen-activated protein kinase kinase 1; MAPK14, mitogen-activated protein kinase 14; PAK1: p21 (RAC1) activated kinase 1; PDK1: pyruvate dehydrogenase kinase 1; PGK1, phosphoglycerate kinase 1; PTMs: post-translational modifications; RAC1: Rac family small GTPase 1; SQSTM1: sequestosome 1; TCGA, The Cancer Genome Atlas.


Assuntos
Proteína 5 Relacionada à Autofagia/metabolismo , Autofagia/fisiologia , Hipóxia/metabolismo , Quinases Ativadas por p21/metabolismo , Neoplasias Encefálicas/metabolismo , Carcinogênese/metabolismo , Glioblastoma/patologia , Glioma/tratamento farmacológico , Humanos , Processamento de Proteína Pós-Traducional/fisiologia , Transdução de Sinais/fisiologia
4.
J Int Med Res ; 48(8): 300060520949404, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32865074

RESUMO

OBJECTIVE: Clinical characteristics of patients with pyogenic liver abscess (PLA) of varying etiologies may be different. This study aimed to analyze the clinical characteristics, pathogenic bacteria, treatment, and prognosis of patients with PLA associated with diabetes and biliary disease. METHODS: Clinical, imaging, and laboratory data from 202 inpatients with PLA were retrospectively analyzed. RESULTS: Eighty-eight patients (43.6%) had a history of diabetes, 73 (36.1%) had a history of underlying biliary tract disease, and 24 (11.9%) had both the diseases. The level of C-reactive protein (CRP) increased in 99.2% (119/120) patients, and the level of procalcitonin (PCT) increased in 95.5% (148/155) patients. The main pathogen of PLA was Klebsiella pneumoniae. The incidence of bloodstream infection increased by 34.4% (22/64) in patients with PLA that was associated with diabetes mellitus, and that of K. pneumoniae infection was 88.6% (39/44). The readmission rate for patients with PLA with underlying biliary diseases was 10.2 to 12.5%. CONCLUSION: The main pathogen of PLA is K. pneumoniae, which is sensitive to most antibiotics. Patients with PLA associated with diabetes were more likely to have bloodstream infections, and the recurrence rate of PLA with underlying biliary diseases was higher than without biliary duct disease.


Assuntos
Doenças Biliares , Diabetes Mellitus , Infecções por Klebsiella , Abscesso Hepático Piogênico , Doenças Biliares/complicações , Doenças Biliares/diagnóstico , Humanos , Infecções por Klebsiella/complicações , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae , Abscesso Hepático Piogênico/complicações , Abscesso Hepático Piogênico/diagnóstico , Estudos Retrospectivos
5.
Theranostics ; 10(3): 1046-1059, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31938050

RESUMO

Resistance to the chemotherapeutic drug 5'-azacytidine (5'-AZA) is a major obstacle in the treatment of patients with acute myeloid leukemia (AML). The uridine-cytidine kinase 1 (UCK1) has an established role in activating 5'-AZA and its protein level is significantly downregulated in patients resistant to the drug. However, the underlying molecular mechanism for the reduced UCK1 expression remains to be elucidated. Methods: Using mass spectrometry and molecular biochemistry analyses, we identified specific enzymes mediating UCK1 degradation. Human AML cell lines and murine AML model were used to characterize the effects of these enzymes on 5'-AZA resistance. Results: We demonstrated that the ubiquitin E3 ligase KLHL2 interacted with UCK1 and mediated its polyubiquitination at the K81 residue and degradation. We showed that deubiquitinase USP28 antagonized KLHL2-mediated polyubiquitylation of UCK1. We also provided evidence that ATM-mediated phosphorylation of USP28 resulted in its disassociation from KLHL2 and UCK1 destabilization. Conversely, UCK1 phosphorylation by 5'-AZA-activated ATM enhanced the KLHL2-UCK1 complex formation. Importantly, silencing KLHL2 or USP28 overexpression not only inhibited AML cell proliferation but also sensitized AML cells to 5'-AZA-induced apoptosis in vitro and in vivo. These results were no longer observed in USP28-deficient cells. Conclusions: Our study revealed a novel mechanism by which the KLHL2/USP28/ATM axis mediates resistance of AML cells to 5'-AZA by regulating UCK1 ubiquitination and phosphorylation. These results have direct clinical implications and provide a rationale for the combination drug treatment of AML patients.


Assuntos
Azacitidina , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos , Leucemia Mieloide Aguda , Proteínas dos Microfilamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ubiquitina Tiolesterase/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Azacitidina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Células HEK293 , Células HL-60 , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Uridina Quinase/metabolismo
6.
Autophagy ; 15(8): 1419-1437, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30870073

RESUMO

N6-methyladenosine (m6A) mRNA modifications play critical roles in various biological processes. However, no study addresses the role of m6A in macroautophagy/autophagy. Here, we show that m6A modifications are increased in H/R-treated cardiomyocytes and ischemia/reperfusion (I/R)-treated mice heart. We found that METTL3 (methyltransferase like 3) is the primary factor involved in aberrant m6A modification. Silencing METTL3 enhances autophagic flux and inhibits apoptosis in H/R-treated cardiomyocytes. However, overexpression of METTL3 or inhibition of the RNA demethylase ALKBH5 has an opposite effect, suggesting that METTL3 is a negative regulator of autophagy. Mechanistically, METTL3 methylates TFEB, a master regulator of lysosomal biogenesis and autophagy genes, at two m6A residues in the 3'-UTR, which promotes the association of the RNA-binding protein HNRNPD with TFEB pre-mRNA and subsequently decreases the expression levels of TFEB. Further experiments show that autophagic flux enhanced by METTL3 deficiency is TFEB dependent. In turn, TFEB regulates the expression levels of METTL3 and ALKBH5 in opposite directions: it induces ALKBH5 and inhibits METTL3. TFEB binds to the ALKBH5 promoter and activates its transcription. In contrast, inhibition of METTL3 by TFEB does not involve transcriptional repression but rather downregulation of mRNA stability, thereby establishing a negative feedback loop. Together, our work uncovers a critical link between METTL3-ALKBH5 and autophagy, providing insight into the functional importance of the reversible mRNA m6A methylation and its modulators in ischemic heart disease. Abbreviations: ACTB, actin beta; ALKBH5, alkB homolog 5, RNA demethylase; ANXA5, annexin A5; ATG, autophagy-related; BafA, bafilomycin A1; CASP3, caspase 3; ELAVL1, ELAV like RNA binding protein 1; FTO, FTO, alpha-ketoglutarate dependent dioxygenase; GFP, green fluorescent protein; GST, glutathione S-transferase; HNRNPD, heterogeneous nuclear ribonucleoprotein D; H/R, hypoxia/reoxygenation; I/R, ischemia/reperfusion; LAD, left anterior descending; m6A, N6-methyladenosine; MEFs, mouse embryo fibroblasts; Mer, mutated estrogen receptor domains; METTL3, methyltransferase like 3; METTL14, methyltransferase like 14; mRFP, monomeric red fluorescent protein; MTORC1, mechanistic target of rapamycin kinase complex 1; NMVCs, neonatal mouse ventricular cardiomyocytes; PCNA, proliferating cell nuclear antigen; PE, phosphatidylethanolamine; PI, propidium iodide; PTMs, post-translational modifications; PVDF, polyvinylidenedifluoride; RIP, RNA-immunoprecipitation; siRNA, small interfering RNA; SQSTM1, sequestosome 1; TFEB, transcription factor EB; TUBA: tublin alpha; WTAP, WT1 associated protein; YTHDF, YTH N6-methyladenosine RNA binding protein.


Assuntos
Adenosina/análogos & derivados , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Metiltransferases/metabolismo , Miócitos Cardíacos/metabolismo , Oxigênio/farmacologia , Adenosina/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Hipóxia Celular/efeitos dos fármacos , Células HEK293 , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/metabolismo , Humanos , Metilação , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Precursores de RNA/metabolismo , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ativação Transcricional/genética , Regulação para Cima/efeitos dos fármacos
7.
Autophagy ; 14(5): 825-844, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29634390

RESUMO

Post-translational modifications of autophagy-related (ATG) genes are necessary to modulate their functions. However, ATG protein methylation and its physiological role have not yet been elucidated. The methylation of non-histone proteins by SETD7, a SET domain-containing lysine methyltransferase, is a novel regulatory mechanism to control cell protein function in response to various cellular stresses. Here we present evidence that the precise activity of ATG16L1 protein in hypoxia/reoxygenation (H/R)-treated cardiomyocytes is regulated by a balanced methylation and phosphorylation switch. We first show that H/R promotes autophagy and decreases SETD7 expression, whereas autophagy inhibition by 3-MA increases SETD7 level in cardiomyocytes, implying a tight correlation between autophagy and SETD7. Then we demonstrate that SETD7 methylates ATG16L1 at lysine 151 while KDM1A/LSD1 (lysine demethylase 1A) removes this methyl mark. Furthermore, we validate that this methylation at lysine 151 impairs the binding of ATG16L1 to the ATG12-ATG5 conjugate, leading to inhibition of autophagy and increased apoptosis in H/R-treated cardiomyocytes. However, the cardiomyocytes with shRNA-knocked down SETD7 or inhibition of SETD7 activity by a small molecule chemical, display increased autophagy and decreased apoptosis following H/R treatment. Additionally, methylation at lysine 151 inhibits phosphorylation of ATG16L1 at S139 by CSNK2 which was previously shown to be critical for autophagy maintenance, and vice versa. Together, our findings define a novel modification of ATG16L1 and highlight the importance of an ATG16L1 phosphorylation-methylation switch in determining the fate of H/R-treated cardiomyocytes.


Assuntos
Apoptose , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas de Transporte/metabolismo , Lisina/metabolismo , Miócitos Cardíacos/metabolismo , Oxigênio/farmacologia , Sequência de Aminoácidos , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteínas de Transporte/química , Hipóxia Celular/efeitos dos fármacos , Células HEK293 , Histona Desmetilases/metabolismo , Histona-Lisina N-Metiltransferase , Humanos , Metilação/efeitos dos fármacos , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Proteínas Metiltransferases/metabolismo , Ratos , Proteínas de Transporte Vesicular/metabolismo
8.
Autophagy ; 11(8): 1308-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26083323

RESUMO

Recent studies have shown that the phosphorylation and dephosphorylation of ULK1 and ATG13 are related to autophagy activity. Although ATG16L1 is absolutely required for autophagy induction by affecting the formation of autophagosomes, the post-translational modification of ATG16L1 remains elusive. Here, we explored the regulatory mechanism and role of ATG16L1 phosphorylation for autophagy induction in cardiomyocytes. We showed that ATG16L1 was a phosphoprotein, because phosphorylation of ATG16L1 was detected in rat cardiomyocytes during hypoxia/reoxygenation (H/R). We not only demonstrated that CSNK2 (casein kinase 2) phosphorylated ATG16L1, but also identified the highly conserved Ser139 as the critical phosphorylation residue for CSNK2. We further established that ATG16L1 associated with the ATG12-ATG5 complex in a Ser139 phosphorylation-dependent manner. In agreement with this finding, CSNK2 inhibitor disrupted the ATG12-ATG5-ATG16L1 complex. Importantly, phosphorylation of ATG16L1 on Ser139 was responsible for H/R-induced autophagy in cardiomyocytes, which protects cardiomyocytes from apoptosis. Conversely, we determined that wild-type PPP1 (protein phosphatase 1), but not the inactive mutant, associated with ATG16L1 and antagonized CSNK2-mediated phosphorylation of ATG16L1. Interestingly, one RVxF consensus site for PPP1 binding in the C-terminal tail of ATG16L1 was identified; mutation of this site disrupted its association with ATG16L1. Notably, CSNK2 also associated with PPP1, but ATG16L1 depletion impaired the interaction between CSNK2 and PPP1. Collectively, these data identify ATG16L1 as a bona fide physiological CSNK2 and PPP1 substrate, which reveals a novel molecular link from CSNK2 to activation of the autophagy-specific ATG12-ATG5-ATG16L1 complex and autophagy induction.


Assuntos
Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica , Miócitos Cardíacos/citologia , Proteína Fosfatase 1/metabolismo , Sequência de Aminoácidos , Animais , Apoptose , Autofagia , Proteína 5 Relacionada à Autofagia , Proteínas Relacionadas à Autofagia , Sítios de Ligação , Caseína Quinase II/metabolismo , Hipóxia Celular , Linhagem da Célula , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Dados de Sequência Molecular , Oxigênio/química , Fosforilação , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/metabolismo , Traumatismo por Reperfusão , Homologia de Sequência de Aminoácidos , Serina/química
9.
Tohoku J Exp Med ; 235(4): 261-6, 2015 04.
Artigo em Inglês | MEDLINE | ID: mdl-25797214

RESUMO

Coronary heart disease (CHD) is a disease resulting from the interaction between genetic variations and environmental factors. Zinc finger homeobox 3 (ZFHX3) is a transcription factor and contains a poly-glutamine tract in a compositionally biased region that is encoded by exon 9, containing a cluster of CAG and CAA triplets followed by the polymorphic CAA repeats: (CAG)2(CAA)2(CAG)3CAACAG(CAA)nGCA. Thus, nine successive glutamine residues precede the poly-glutamine tract, encoded by the polymorphic CAA repeats. The aim of this study was to investigate the association of the CAA repeat polymorphism in exon 9 of the ZFHX3 gene with the risk of CHD in a Chinese population. The CAA repeat polymorphism was determined by polymerase chain reaction followed by DNA sequencing in 321 CHD patients. Genotype frequencies were compared using the non-parametric mood median test. Four alleles of CAG(CAA)10GCA, CAG(CAA)8GCA, CAG(CAA)9GCA, and CAG(CAA)11GCA were found in Chinese CHD patients in exon 9 of the ZFHX3 gene. The CAG(CAA)10GCA was a major allele (95.95%), and the CAG(CAA)8GCA was a minor allele (3.58%). The CAG(CAA)9GCA and CAG(CAA)11GCA were rare alleles (0.31% and 0.16%). The CAG(CAA)10GCA allele encodes a poly-glutamine tract of 19 residues. Importantly, the CHD patients homozygous for the CAG(CAA)10GCA allele had a higher risk of CHD, compared to the heterozygous patients carrying a CAG(CAA)8GCA allele. Moreover, the CAG(CAA)10GCA allele was significantly associated with hypertension, diabetes mellitus, or dyslipidemia (P < 0.05). Thus, the CAA repeat polymorphism in exon 9 of the ZFHX3 gene contributes to the CHD susceptibility in the Chinese population.


Assuntos
Povo Asiático/genética , Doença da Artéria Coronariana/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Proteínas de Homeodomínio/genética , Polimorfismo Genético , Expansão das Repetições de Trinucleotídeos/genética , Alelos , Sequência de Bases , China , Diabetes Mellitus/genética , Dislipidemias/complicações , Dislipidemias/genética , Feminino , Frequência do Gene , Humanos , Hipertensão/complicações , Hipertensão/genética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular
10.
Hepatology ; 60(5): 1659-73, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25042864

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is a highly vascularized tumor with frequent extrahepatic metastasis. Active angiogenesis and metastasis are responsible for rapid recurrence and poor survival of HCC. However, the mechanisms that contribute to tumor metastasis remain unclear. Here we evaluate the effects of ATPase inhibitory factor 1 (IF1), an inhibitor of the mitochondrial H(+)-adenosine triphosphate (ATP) synthase, on HCC angiogenesis and metastasis. We found that increased expression of IF1 in human HCC predicts poor survival and disease recurrence after surgery. Patients with HCC who have large tumors, with vascular invasion and metastasis, expressed high levels of IF1. Invasive tumors overexpressing IF1 were featured by active epithelial-mesenchymal transition (EMT) and increased angiogenesis, whereas silencing IF1 expression attenuated EMT and invasion of HCC cells. Mechanistically, IF1 promoted Snai1 and vascular endothelial growth factor (VEGF) expression by way of activating nuclear factor kappa B (NF-κB) signaling, which depended on the binding of tumor necrosis factor (TNF) receptor-associated factor 1 (TRAF1) to NF-κB-inducing kinase (NIK) and the disruption of NIK association with the TRAF2-cIAP2 complex. Suppression of the NF-κB pathway interfered with IF1-mediated EMT and invasion. Chromatin immunoprecipitation assay showed that NF-κB can bind to the Snai1 promoter and trigger its transcription. IF1 was directly transcribed by NF-κB, thus forming a positive feedback signaling loop. There was a significant correlation between IF1 expression and pp65 levels in a cohort of HCC biopsies, and the combination of these two parameters was a more powerful predictor of poor prognosis. CONCLUSION: IF1 promotes HCC angiogenesis and metastasis by up-regulation of Snai1 and VEGF transcription, thereby providing new insight into HCC progression and IF1 function. (Hepatology 2014;60:1659-1673).


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , NF-kappa B/metabolismo , Neovascularização Patológica/metabolismo , Proteínas/metabolismo , Animais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular , China/epidemiologia , Estudos de Coortes , Transição Epitelial-Mesenquimal , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Fosfoproteínas , Prognóstico , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo , Ativação Transcricional , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas da Matriz Viral
11.
Gut ; 63(10): 1635-47, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24352616

RESUMO

BACKGROUND: Mounting epidemiological evidence supports a role for phosphatase and tensin homologue (PTEN)-T cell leukaemia 1 (Tcl1) signalling deregulation in hepatocarcinogenesis. OBJECTIVE: To determine the molecular and biochemical mechanisms by which the PTEN/Tcl1 axis regulates the pentose phosphate pathway (PPP) in hepatocellular carcinoma (HCC). METHODS: We compared levels of PTEN and glucose-6-phosphate dehydrogenase (G6PD) mRNA in human HCC and healthy liver tissue. We measured PPP flux, glucose consumption, lactate production, nicotinamide adenine dinucleotide phosphate (NADPH) levels and lipid accumulation. We investigated the PTEN/Tcl1 axis using molecular biology, biochemistry and mass spectrometry analysis. We assessed proliferation, apoptosis and senescence in cultured cells, and tumour formation in mice. RESULTS: We showed that PTEN inhibited the PPP pathway in human liver tumours. Through the PPP, PTEN suppressed glucose consumption and biosynthesis. Mechanistically, the PTEN protein bound to G6PD, the first and rate-limiting enzyme of the PPP and prevented the formation of the active G6PD dimer. Tcl1, a coactivator for Akt, reversed the effects of PTEN on biosynthesis. Tcl1 promoted G6PD activity and also increased G6PD pre-mRNA splicing and protein expression in a heterogeneous nuclear ribonucleoprotein (hnRNPK)-dependent manner. PTEN also formed a complex with hnRNPK, which inhibited G6PD pre-mRNA splicing. Moreover, PTEN inactivated Tcl1 via glycogen synthase kinase-3ß (GSK3ß)-mediated phosphorylation. Importantly, Tcl1 knockdown enhanced the sensitivity of HCC to sorafenib, whereas G6PD knockdown inhibited hepatocarcinogenesis. CONCLUSIONS: These results establish the counteraction between PTEN and Tcl1 as a key mechanism that regulates the PPP and suggest that targeting the PTEN/Tcl1/hnRNPK/G6PD axis could open up possibilities for therapeutic intervention and improve the prognosis of patients with HCC.


Assuntos
Carcinoma Hepatocelular/genética , Glucosefosfato Desidrogenase/genética , Neoplasias Hepáticas Experimentais/genética , PTEN Fosfo-Hidrolase/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Precursores de RNA/genética , Splicing de RNA , Ribonucleoproteínas/metabolismo , Animais , Carcinoma Hepatocelular/metabolismo , Glucose/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Glicogênio Sintase/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo K , Humanos , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Via de Pentose Fosfato/fisiologia , Fosforilação
12.
Indian J Pediatr ; 81(7): 722-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23900752

RESUMO

OBJECTIVE: To find the length and location of the deletions in the short arm of chromosome 5 in one case of Cri du Chat syndrome using oligo array comparative genomic hybridization. METHODS: Metaphase chromosomes were prepared from peripheral blood lymphocyte cultures using standard cytogenetic protocols. Chromosomal analysis was done in G-banded metaphases. Oligo array comparative genomic hybridization and fluorescence in situ hybridization were performed by the commercially available kits. RESULTS: Oligonucleotide array comparative genomic hybridization (CGH) analysis revealed a 23.263 Mb deletion at region 5p14.2-->qter, combined with a duplication of 14.602 Mb in size in the area 12p13.1-->pter. Chromosomal aberrations were confirmed by fluorescence in situ hybridization. The male neonate with Cri du Chat syndrome had an unbalanced translocation which was inherited from his father who was a balanced carrier with a karyotype 46, XY, t (5; 12) (p14.2; p13.1). CONCLUSIONS: This report shows the clinical utility of the oligonucleotide array in the detection of submicroscopic chromosomal aberrations, thus improving the molecular diagnosis of Cri du Chat syndrome.


Assuntos
Aberrações Cromossômicas , Deleção Cromossômica , Cromossomos Humanos Par 5 , Síndrome de Cri-du-Chat/genética , Humanos , Recém-Nascido , Masculino
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(3): 628-32, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23815911

RESUMO

This study was aimed to explore the effect of BCL11A gene on transcription of γ-globin gene in K562 cells. B-cell lymphoma/leukemia 11A (BCL11A) gene was silenced by small interfering RNA (siRNA) expression vectors in K562 cells (human erythroblastic leukemia cell line). Gamma-globin mRNA level in K562 cells was determined by RT-PCR. Association between the BCL11A gene and γ-globin gene transcription was explored by comparison of mRNA levels. The results indicated that the silence rate of the BCL11A gene in K562 cells by 4 siRNA expression vectors was 49.7%, 55.4%, 78.2%, and 84.1%, respectively. The siRNA expression vector with 84.1% silence rate was transfected into K562 cells, transcription level of γ-globin mRNA in K562 cells transfected with siRNA expression vector increased 2.4 times as compared with control K562 cells. It is concluded that level of γ-globin mRNA increases when the BCL11A gene is silenced. It indicates that the BCL11A gene may be a negative regulator for γ-globin gene expression.


Assuntos
Proteínas de Transporte/genética , Proteínas Nucleares/genética , Transcrição Gênica , gama-Globinas/genética , Regulação Leucêmica da Expressão Gênica , Genes Reguladores , Vetores Genéticos , Humanos , Células K562 , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Repressoras , Transfecção
14.
J Clin Gastroenterol ; 45(4): 337-41, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20871410

RESUMO

BACKGROUND AND OBJECTIVE: There is no consensus concerning small bowel preparation before capsule endoscopy (CE). This study evaluated the effects of 4 regimens on small bowel cleansing and diagnostic yield. METHODS: Patients were randomly divided into 4 groups. Group A consumed a clear liquid diet after lunch on the day before CE, followed by overnight fasting. Group B took 250 mL 20% mannitol and 1 L 0.9% saline orally at 05:00 hours on the day of the procedure. In group C, the same regimen was taken at 20:00 hours on the day before and at 05:00 hours on the day of CE. In group D, in addition to the group C regimen, 20 mL oral simethicone was taken 30 minutes before CE. RESULTS: Two hundred patients were prospectively enrolled, and 7 were excluded from the final analysis because of incomplete small bowel transit. No significant difference was noted among the 4 groups for small bowel transit time. Bowel preparation in group D was significantly better than for the other regimens for overall cleansing of the proximal small bowel, and showed improved overall cleansing of the distal small bowel when compared with 10-hours overnight fasting. Pathological lesions of the proximal and distal small bowel were, respectively, achieved in 82 and 74 patients, mostly distributed in group D. CONCLUSIONS: Small bowel preparation that involves split-dose oral mannitol plus single-dose simethicone for CE can improve mucosal visualization and subsequent diagnostic yield when compared with 10-hours overnight fasting.


Assuntos
Antiespumantes/uso terapêutico , Endoscopia por Cápsula/métodos , Diuréticos Osmóticos/uso terapêutico , Intestino Delgado/efeitos dos fármacos , Manitol/uso terapêutico , Pré-Medicação , Simeticone/uso terapêutico , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antiespumantes/administração & dosagem , Diuréticos Osmóticos/administração & dosagem , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Trânsito Gastrointestinal/efeitos dos fármacos , Humanos , Masculino , Manitol/administração & dosagem , Pessoa de Meia-Idade , Estudos Prospectivos , Simeticone/administração & dosagem , Irrigação Terapêutica/métodos , Resultado do Tratamento , Adulto Jovem
15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 27(3): 272-5, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20533264

RESUMO

OBJECTIVE: To investigate the splice variants of the calpain 3 gene existing in human skeletal muscle tissue and white blood cells, and to explore the feasibility of gene diagnosis using CAPN3 mRNA extracted from peripheral leukocytes. METHODS: Total RNA was extracted from peripheral blood and skeletal muscle tissue in healthy individuals. CAPN3 cDNAs were determined by reverse transcriptase polymerase chain reaction and DNA sequencing. CAPN3 cDNAs from peripheral leukocytes were compared with sequences obtained from skeletal muscle tissue. RESULTS: RT-PCR and DNA sequencing showed that the CAPN3 cDNAs comprised 24 exons in human skeletal muscle tissue, while the number of exons was 23 in white blood cells. Exon 15 was spliced out in human white blood cells. CONCLUSION: Splice variants exist in human skeletal muscle tissue and white blood cells. Gene diagnosis may omit the mutations of exon 15 using mRNA extracted from peripheral leukocytes. These findings suggest that mutation analysis of the CAPN3 cDNA should use skeletal muscle tissue as materials instead of peripheral blood.


Assuntos
Calpaína/genética , Leucócitos/metabolismo , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Análise Mutacional de DNA , DNA Complementar/genética , Éxons/genética , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Zhonghua Xin Xue Guan Bing Za Zhi ; 36(8): 735-7, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19100118

RESUMO

OBJECTIVE: To explore if the hypoxia/reoxygenation-induced increased activity and expression of PTP-1B in neonatal rat cardiomyocytes are mediated by nitric oxide (NO). METHODS: Neonatal rat cardiomyocytes were isolated and randomly divided into 4 groups: normal group (N group); hypoxia/reoxygenation group (H/R group); N(omega)-nitro-l-arginine methylester treated group (L-NAME group); hypoxia/reoxygenation plus L-NAME group (L-NA + H/R group). PTP-1B activity in cardiomyocytes was determined spectrophotometrically at 405 nm, PTP-1B expression in cardiomyocytes was detected by Western blot.NO and LDH concentrations in cell medium were also assayed. RESULTS: PTP-1B activity and expression in cardiomyocytes was significantly higher in the H/R group as compared to the N group and this increase could be blocked by cotreatment with L-NAME. As compared to H/R group, nitric oxide and LDH concentrations in cell medium were significantly decreased in the L-NA + H/R group (NO concentration: H/R group, 368% +/- 13% and L-NA + H/R group, 61% +/- 7%, P < 0.005; LDH concentration: H/R group, 41.2 +/- 6.7 and L-NA + H/R group, 23.6 +/- 4.8, P < 0.05). CONCLUSIONS: This study showed that pretreatment with L-NAME, a non-selective inhibitor of NOS, prevented the hypoxia/reoxygenation-induced increase in PTP-1B activity and expression in cardiomyocytes, suggesting PTP-1B activation during hypoxia/reoxygenation was mediated by nitric oxide.


Assuntos
Miócitos Cardíacos/metabolismo , Óxido Nítrico/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Animais , Hipóxia Celular , Células Cultivadas , Miócitos Cardíacos/citologia , NG-Nitroarginina Metil Éster/farmacologia , Ratos
17.
Apoptosis ; 13(3): 383-93, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18278556

RESUMO

OBJECTIVE: To investigate the effect of siRNA against PTP-1B on neonatal rat cardiac myocyte apoptosis induced by hypoxia-reoxygenation (H/R) and its molecular mechanisms. METHODS: Isolated neonatal and adult rat cardiac myocytes were cultured for 24 h after PTP-1B siRNA transfection, and with 2, 4 and 6 h of hypoxia followed by 6 h of reoxygenation (H/R). The cardiac myocyte apoptosis induced by the treatments was assessed by TUNEL staining. Levels of PTP-1B and phospho-Akt were determined by Western blot, colorimetric assay kits were used to measure activities of caspase-3 and 8, and co-immunoprecipitation was used to check the amount of PTP-1B bound to FasR. Sodium orthovanadate, a general pharmacological phosphatase blocker and LY294002, an inhibitor of PI3-kinase/Akt pathway, were respectively used to inhibit PTP-1B and Akt activity. RESULTS: H/R resulted in severe injury in cultured rat cardiomyocytes and upregulated PTP-1B expression. However, siRNA against PTP-1B significantly decreased the number of apoptotic cardiomyocytes induced by 4H/6R as compared with cells without siRNA treatment (Apoptotic index: 12.1 +/- 1.4% vs. 23.2 +/- 1.6%, P < 0.05), along with greater phosphorylation of Akt, reduced activities of caspase-3 and 8, and the lower association of PTP-1B with FasR. Vanadate and LY294002 also partly reduced apoptosis of cardiomyocytes induced by 4H/6R. CONCLUSIONS: PTP-1B is a key regulator of apoptosis of cardiomyocytes induced by H/R, and siRNA against PTP-1B effectively protects cardiomyocytes against H/R injury, the mechanisms of which might be associated with Akt activation, the reduction of both caspase-3 and 8 activities, and the lower amount of PTP-1B bound to FasR.


Assuntos
Apoptose , Hipóxia/fisiopatologia , Miócitos Cardíacos/citologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Envelhecimento , Animais , Inibidores de Caspase , Células Cultivadas , Cromonas/farmacologia , Marcação In Situ das Extremidades Cortadas , Precondicionamento Isquêmico Miocárdico , Masculino , Morfolinas/farmacologia , Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/biossíntese , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Regulação para Cima , Vanadatos/farmacologia
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