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1.
J Med Virol ; 95(12): e29325, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38108211

RESUMO

Hepatitis B virus (HBV) hijacks autophagy for its replication. Nucleos(t)ide analogs (NUCs) treatment suppressed HBV replication and reduced hepatocellular carcinoma (HCC) incidence. However, the use of NUCs in chronic hepatitis B (CHB) patients with normal or minimally elevated serum alanine aminotransferase (ALT) levels is still debated. Animal models are crucial for studying the unanswered issue and evaluating new therapies. MicroRNA-122 (miR-122), which regulates fatty acid and cholesterol metabolism, is downregulated during hepatitis and HCC progression. The reciprocal inhibition of miR-122 with HBV highlights its role in HCC development as a tumor suppressor. By crossbreeding HBV-transgenic mice with miR-122 knockout mice, we generated a hybrid mouse model with a high incidence of HCC up to 89% and normal ALT levels before HCC. The model exhibited early-onset hepatic steatosis, progressive liver fibrosis, and impaired late-phase autophagy. Metabolomics and microarray analysis identified metabolic signatures, including dysregulation of lipid metabolism, inflammation, genomic instability, the Warburg effect, reduced TCA cycle flux, energy deficiency, and impaired free radical scavenging. Antiviral treatment reduced HCC incidence in hybrid mice by approximately 30-35% compared to untreated mice. This effect was linked to the activation of ER stress-responsive transcription factor ATF4, clearance of autophagosome cargo p62, and suppression of the CHOP-mediated apoptosis pathway. In summary, this study suggests that despite minimal ALT elevation, HBV replication can lead to liver injury. Endoplasmic reticulum stress, reduced miR-122 levels, mitochondrial and metabolic dysfunctions, blocking protective autophagy resulting in p62 accumulation, apoptosis, fibrosis, and HCC. Antiviral may improve the above-mentioned pathogenesis through HBV suppression.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , MicroRNAs , Humanos , Camundongos , Animais , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/metabolismo , Replicação Viral , Antivirais/uso terapêutico , Antivirais/farmacologia
3.
J Formos Med Assoc ; 118(10): 1450-1457, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31471221

RESUMO

BACKGROUND/PURPOSE: Enhanced recovery after surgery (ERAS) is a growing tendency in modern perioperative period management, but no protocol has been established for a strategy that optimally facilitates rapid recovery from anesthesia. We hypothesized that applying a total intravenous anesthesia (TIVA) method to the response surface model (RSM) would allow prediction of the emergence and endotracheal tube extubation in cases undergoing video-assisted thoracotomy surgery (VATS). METHODS: Thirty patients who were scheduled to undergo VATs under TIVA were enrolled. Pharmacokinetic profiles were calculated using a Tivatrainer. Emergence from anesthesia was observed and the exact time point of the regained response (RR) was recorded. The effect of concentration was analyzed and applied to a response surface model. RESULTS: The cumulative prediction curve of the RR was closer to the 50% probability as set by the OAA/S ≥ 4 than by the OAA/S ≥ 2 model. The median, averages, and standard deviations of the time differences were 14.5, 22.05 ± 19.23 min for the OAA/S ≥2 model and 10.4, 14.26 ± 10.40 min for the OAA/S ≥ 4 model. CONCLUSION: The OAA/S ≥ 4 model could identify the target concentration in propofol-remifentanil pairs that predicted the time of emergence from VATS in 10 min. Our results indicate that RSM can be used to derive an ERAS protocol for VATS under TIVA. Further studies should investigate application of RSM to predict ERAS for various types of procedures.


Assuntos
Extubação , Anestesia Geral , Recuperação Pós-Cirúrgica Melhorada , Modelos Teóricos , Adulto , Idoso , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/farmacocinética , Período de Recuperação da Anestesia , Anestésicos Intravenosos/administração & dosagem , Anestésicos Intravenosos/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Propofol/administração & dosagem , Propofol/farmacocinética , Remifentanil/administração & dosagem , Remifentanil/farmacocinética , Cirurgia Torácica Vídeoassistida , Fatores de Tempo
4.
J Cell Mol Med ; 22(5): 2631-2643, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29502342

RESUMO

Caveolin-1 (Cav1) is down-regulated during MK4 (MDCK cells harbouring inducible Ha-RasV12 gene) transformation by Ha-RasV12 . Cav1 overexpression abrogates the Ha-RasV12 -driven transformation of MK4 cells; however, the targeted down-regulation of Cav1 is not sufficient to mimic this transformation. Cav1-silenced cells, including MK4/shCav1 cells and MDCK/shCav1 cells, showed an increased cell area and discontinuous junction-related proteins staining. Cellular and mechanical transformations were completed when MDCK/shCav1 cells were treated with medium conditioned by MK4 cells treated with IPTG (MK4+I-CM) but not with medium conditioned by MK4 cells. Nanoparticle tracking analysis showed that Ha-RasV12 -inducing MK4 cells increased exosome-like microvesicles release compared with their normal counterparts. The cellular and mechanical transformation activities of MK4+I-CM were abolished after heat treatment and exosome depletion and were copied by exosomes derived from MK4+I-CM (MK4+I-EXs). Wnt5a, a downstream product of Ha-RasV12 , was markedly secreted by MK4+I-CM and MK4+I-EXs. Suppression of Wnt5a expression and secretion using the porcupine inhibitor C59 or Wnt5a siRNA inhibited the Ha-RasV12 - and MK4+I-CM-induced transformation of MK4 cells and MDCK/shCav1 cells, respectively. Cav1 down-regulation, either by Ha-RasV12 or targeted shRNA, increased frizzled-2 (Fzd2) protein levels without affecting its mRNA levels, suggesting a novel role of Cav1 in negatively regulating Fzd2 expression. Additionally, silencing Cav1 facilitated the internalization of MK4+I-EXs in MDCK cells. These data suggest that Cav1-dependent repression of Fzd2 and exosome uptake is potentially relevant to its antitransformation activity, which hinders the activation of Ha-RasV12 -Wnt5a-Stat3 pathway. Altogether, these results suggest that both decreasing Cav1 and increasing exosomal Wnt5a must be implemented during Ha-RasV12 -driven cell transformation.


Assuntos
Caveolina 1/genética , Transformação Celular Neoplásica/genética , Regulação para Baixo/genética , Receptores Frizzled/metabolismo , Transdução de Sinais , Proteína Wnt-5a/metabolismo , Proteínas ras/metabolismo , Animais , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/patologia , Meios de Cultivo Condicionados/farmacologia , Cães , Regulação para Baixo/efeitos dos fármacos , Exossomos/efeitos dos fármacos , Exossomos/metabolismo , Humanos , Isopropiltiogalactosídeo/farmacologia , Células Madin Darby de Rim Canino , Fator de Transcrição STAT3/metabolismo , Regulação para Cima/efeitos dos fármacos
5.
Oncotarget ; 6(25): 20946-58, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26189182

RESUMO

The stiffness sensing ability is required to respond to the stiffness of the matrix. Here we determined whether normal cells and cancer cells display distinct mechanical phenotypes. Cancer cells were softer than their normal counterparts, regardless of the type of cancer (breast, bladder, cervix, pancreas, or Ha-RasV12-transformed cells). When cultured on matrices of varying stiffness, low stiffness decreased proliferation in normal cells, while cancer cells and transformed cells lost this response. Thus, cancer cells undergo a change in their mechanical phenotype that includes cell softening and loss of stiffness sensing. Caveolin-1, which is suppressed in many tumor cells and in oncogene-transformed cells, regulates the mechanical phenotype. Caveolin-1-upregulated RhoA activity and Y397FAK phosphorylation directed actin cap formation, which was positively correlated with cell elasticity and stiffness sensing in fibroblasts. Ha-RasV12-induced transformation and changes in the mechanical phenotypes were reversed by re-expression of caveolin-1 and mimicked by the suppression of caveolin-1 in normal fibroblasts. This is the first study to describe this novel role for caveolin-1, linking mechanical phenotype to cell transformation. Furthermore, mechanical characteristics may serve as biomarkers for cell transformation.


Assuntos
Caveolina 1/metabolismo , Neoplasias/patologia , Proteínas ras/metabolismo , Actinas/química , Animais , Fenômenos Biomecânicos , Proliferação de Células , Transformação Celular Neoplásica , Colágeno/química , Cães , Elasticidade , Inibidores Enzimáticos/química , Feminino , Fibroblastos/metabolismo , Genes ras , Humanos , Células Madin Darby de Rim Canino , Camundongos , Microscopia de Força Atômica , Microscopia Confocal , Microscopia de Fluorescência , Células NIH 3T3 , Neoplasias/metabolismo , Fenótipo , Fosforilação , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Proteína rhoA de Ligação ao GTP/metabolismo
7.
PLoS One ; 8(6): e66457, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23805222

RESUMO

BACKGROUND: Whether or not hepatitis B virus (HBV) genotypes, mutations, and viral loads determine outcomes for patients with HBV-induced hepatocellular carcinoma (HCC) remains controversial. AIMS: To study the influence of HBV viral factors on prognoses for patients with HBV-induced HCC after resection surgery and investigate if antiviral therapy could counteract the adverse effects of viral factors. METHODS: A total of 333 HBV-related HCC patients who underwent tumor resection were enrolled retrospectively. Serum HBV DNA levels, mutations, anti-viral therapy, and other clinical variables were analyzed for their association with post-operative recurrence. RESULTS: After a median follow-up of 45.9 months, 208 patients had HCC recurrence after resection. The 5-year overall survival and recurrence-free survival rates were 55.4% and 35.3%, respectively. Multivariate analysis showed indocyanine green retention rate at 15 minutes >10%, gamma-glutamyltransferase (GGT) level >60 U/L, macroscopic and microscopic venous invasion, and the absence of anti-viral therapy were significant risk factors for recurrence. Anti-viral therapy could decrease recurrence in patients with early stage HCC, but the effect was less apparent in those with the Barcelona-Clinic Liver Cancer stage C HCC. For patients without antiviral therapy after resection, serum HBV DNA levels >10(6) copies/mL, GGT >60 U/L, and macroscopic and microscopic venous invasion were significant risk factors predicting recurrence. Among the 216 patients without anti-viral therapy but with complete HBV surface gene mapping data, 73 were with pre-S deletion mutants. Among patients with higher serum HBV DNA levels, those with pre-S deletion had significantly higher rates of recurrence. Moreover, multivariate analysis showed multi-nodularity, macroscopic venous invasion, cirrhosis, advanced tumor cell differentiation, and pre-S deletion were significant risk factors predictive of recurrence. CONCLUSIONS: Ongoing HBV viral replication and pre-S deletion are crucial for determining post-operative tumor recurrence. Anti-viral therapy can help reduce recurrence and improve prognosis, especially for those with early stage HCC.


Assuntos
Antivirais/administração & dosagem , Carcinoma Hepatocelular , DNA Viral , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Hepatite B , Neoplasias Hepáticas , Deleção de Sequência , Carga Viral , Adulto , Idoso , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/virologia , DNA Viral/sangue , DNA Viral/genética , Feminino , Seguimentos , Hepatite B/sangue , Hepatite B/genética , Hepatite B/terapia , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade
8.
Biochim Biophys Acta ; 1782(3): 169-79, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18241680

RESUMO

GTP cyclohydrolase I (GCH), an oligomeric protein composed of 10 identical subunits, is required for the synthesis of neurotransmitters; mutations in GCH are associated with dopa-responsive dystonia (DRD) and hyperphenylalaninemia. Mutated GCH proteins are unstable and prone to dominant-negative effect. We show herein that expression of the GCH mutant GCH-201E or the splicing variant GCH-II caused intracellular inclusion bodies. When Hsp27 was expressed together with the GCH mutants, Hsp27 expression decreased the formation of inclusion bodies by GCH (as assessed by immunofluorescence) and decreased the amount of insoluble GCH mutant proteins (as assessed by Western blot). Transfection of pcDNA-Hsp27-S3D, a phosphorylation-mimicry Hsp27 mutant, was more effective at the mutated GCH proteins than transfection with pcDNA-Hsp27, but okadaic acid, a phosphatase inhibitor, enhanced the effect of pcDNA-Hsp27. Hsp27-S3D also abolished the dominant-negative action of GCH-II. The mutated GCH proteins interacted with the wild-type GCH protein; the inclusion bodies were positive for lysosomal marker LAMP1, soluble in 2% SDS, and were not ubiquitinated. Phophorlyated Hsp27 also decreased the inclusion body formation by the huntingtin polyglutamines. Therefore, diseases involving mutated oligomeric proteins would be manageable by chaperone therapies.


Assuntos
GTP Cicloidrolase/fisiologia , Proteínas de Choque Térmico/farmacologia , Corpos de Inclusão/efeitos dos fármacos , Proteínas de Neoplasias/farmacologia , Animais , Células Cultivadas , Cricetinae , Imunofluorescência , GTP Cicloidrolase/genética , Proteínas de Choque Térmico HSP27 , Chaperonas Moleculares , Mutação , Ácido Okadáico/farmacologia , Fosforilação , Transfecção
9.
Biochem Biophys Res Commun ; 306(4): 937-42, 2003 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-12821132

RESUMO

GTP cyclohydrolase I (GCH, EC 3.5.4.16) regulates the level of tetrahydrobiopterin and in turn the activities of nitric oxide synthase and aromatic amino acid hydroxylases. Type II GCH mRNA, an alternatively spliced species abundant in blood cells, encodes a truncated and nonfunctional protein. When we stimulate peripheral blood mononuclear cells by PHA, the transcription of full-length GCH mRNA increased, but that of type II mRNA decreased transiently. We further demonstrated that the type II cDNA exerted a dominant-negative effect on the wild-type cDNA, similar to the effect of some GCH mutants. Therefore, type II mRNA may regulate GCH and then contribute to the regulation of NO production by BH4-dependent iNOS in mononuclear cells. Selection of the splicing sites may be coupled with transcriptional activation of the GCH gene.


Assuntos
GTP Cicloidrolase/biossíntese , Regulação Enzimológica da Expressão Gênica , Leucócitos Mononucleares/enzimologia , Processamento Alternativo , Western Blotting , Linhagem Celular , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , GTP Cicloidrolase/química , GTP Cicloidrolase/genética , Genes Dominantes , Humanos , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
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