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1.
BMC Cancer ; 24(1): 532, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671389

RESUMO

BACKGROUND: Aberrant expressions of desmoglein 2 (Dsg2) and desmocollin 2(Dsc2), the two most widely distributed desmosomal cadherins, have been found to play various roles in cancer in a context-dependent manner. Their specific roles on breast cancer (BC) and the potential mechanisms remain unclear. METHODS: The expressions of Dsg2 and Dsc2 in human BC tissues and cell lines were assessed by using bioinformatics analysis, immunohistochemistry and western blotting assays. Wound-healing and Transwell assays were performed to evaluate the cells' migration and invasion abilities. Plate colony-forming and MTT assays were used to examine the cells' capacity of proliferation. Mechanically, Dsg2 and Dsc2 knockdown-induced malignant behaviors were elucidated using western blotting assay as well as three inhibitors including MK2206 for AKT, PD98059 for ERK, and XAV-939 for ß-catenin. RESULTS: We found reduced expressions of Dsg2 and Dsc2 in human BC tissues and cell lines compared to normal counterparts. Furthermore, shRNA-mediated downregulation of Dsg2 and Dsc2 could significantly enhance cell proliferation, migration and invasion in triple-negative MDA-MB-231 and luminal MCF-7 BC cells. Mechanistically, EGFR activity was decreased but downstream AKT and ERK pathways were both activated maybe through other activated protein tyrosine kinases in shDsg2 and shDsc2 MDA-MB-231 cells since protein tyrosine kinases are key drivers of triple-negative BC survival. Additionally, AKT inhibitor treatment displayed much stronger capacity to abolish shDsg2 and shDsc2 induced progression compared to ERK inhibition, which was due to feedback activation of AKT pathway induced by ERK inhibition. In contrast, all of EGFR, AKT and ERK activities were attenuated, whereas ß-catenin was accumulated in shDsg2 and shDsc2 MCF-7 cells. These results indicate that EGFR-targeted therapy is not a good choice for BC patients with low Dsg2 or Dsc2 expression. Comparatively, AKT inhibitors may be more helpful to triple-negative BC patients with low Dsg2 or Dsc2 expression, while therapies targeting ß-catenin can be considered for luminal BC patients with low Dsg2 or Dsc2 expression. CONCLUSION: Our finding demonstrate that single knockdown of Dsg2 or Dsc2 could promote proliferation, motility and invasion in triple-negative MDA-MB-231 and luminal MCF-7 cells. Nevertheless, the underlying mechanisms were cellular context-specific and distinct.


Assuntos
Movimento Celular , Proliferação de Células , Desmocolinas , Desmogleína 2 , Neoplasias de Mama Triplo Negativas , Humanos , Desmocolinas/metabolismo , Desmocolinas/genética , Desmogleína 2/metabolismo , Desmogleína 2/genética , Feminino , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/genética , Linhagem Celular Tumoral , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Invasividade Neoplásica , Regulação Neoplásica da Expressão Gênica , beta Catenina/metabolismo , Transdução de Sinais
2.
Huan Jing Ke Xue ; 42(4): 2047-2055, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742840

RESUMO

A pot experiment was carried out to study the impacts of five organic materials (rape straw, broad bean stalk, peat, pig manure compost, and biochar) on the availability of arsenic (As) and cadmium (Cd) in soil, the amount of iron plaque on the root surface, as well as the uptake and translocation of As and Cd in rice grown in an As/Cd co-contaminated yellow paddy soil. The results indicated that the application of organic materials significantly increased the contents of the soil organic matter and the yield of rice. The application of broad bean stalk, peat, pig manure compost, and biochar remarkably increased the soil pH, while the application of rape straw exerted no significant influence. The addition of organic matter reduced the available Cd content by 34.77%-82.69%. However, the effects of organic materials on the availability of As varied with the organic materials. The soil-available As content was significantly increased by the application of pig manure compost and biochar, while it was significantly decreased by adding rape straw and peat. The application of organic materials increased As and Cd contents in the Fe plaques on rice root surface by 28.49%-94.86% and 17.73%-151.03%, respectively. It also reduced the As and Cd contents in brown rice by 27.04%-82.51% and 15.87%-79.45%, respectively. The largest decrease was observed in the biochar treatment. The application of organic materials also remarkably reduced the translocation efficiency of Cd from the root-stem-leaf-grain and that of As from the stem to grain. The correlation analysis revealed that the soil pH, available Cd, and Cd content in the Fe plaques are the major factors influencing the accumulation of Cd in the rice grain. Furthermore, the soil pH, soil organic matter, and As content in the Fe plaques are the major factors influencing the accumulation of As in the rice grain. Therefore, it has been concluded that organic materials could influence the uptake and translocation of As and Cd in rice through changing the soil pH, organic matter content, and As and Cd contents in the Fe plaques.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Animais , Cádmio/análise , Carvão Vegetal , Solo , Poluentes do Solo/análise , Suínos
3.
Huan Jing Ke Xue ; 42(3): 1535-1544, 2021 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742951

RESUMO

To explore the effects of water management and silicon application on the bioavailability of soil arsenic (As) and cadmium (Cd), and the accumulation of As and Cd in rice, pot experiments were carried out using As/Cd co-contaminated paddy soil from a field in Kaiyang County, Guizhou Province. The experimental treatments had the following five water application modes with and without silicon addition:flooding during the entire growth period (T1); flooding for three weeks (0-105 d) after transplanting with wet irrigation (moisture content 50%-60%) during other growth periods (T2); flooding for three weeks before heading (0-65d), three weeks after heading (84-105d), and wet irrigation during other growth periods (T3); flooding from heading to three weeks after heading (84-105d) and wet irrigation during the other growth periods (T4); and wet irrigation during the entire growth period (T5). The results showed that compared with flooding and wet irrigation, flooding combined with wet irrigation was more conducive to the formation of iron plaque (DCB-Fe) on the surfaces of roots. As and Cd content increased with an increasing of content of DCB-Fe. Silicon application increased soil pH and the content of DCB-As but decreased available As and Cd in the soil and, with the exception of the flooding treatment, the DCB-Fe/Cd content. The shorter the flooding time, the higher the accumulation of Cd and the lower the accumulation of As in each part of the rice. Silicon application increased the biomass of rice but decrease the Cd content of roots, stems, leaves, and grain by 4.23%-31.06%, 11.41%-52.90%, 1.74%-35.73%, and 19.25%-39.76%, respectively. Silicon application also decreased the As content of roots, stems, leaves, and grain by 1.47%-52.60%, 6.12%-63.02%, 2.97%-28.41%, and 16.33%-61.23%, respectively. Among the five modes of water application tested, silicon application combined with the T3 mode achieved the highest rice biomass and lowest rice As and Cd contents. Therefore, it is suggested that selecting water management and silicon application regimes according to the level of As/Cd pollution can effectively decrease the bioavailability of As/Cd in the soil, thereby reducing the accumulation of As/Cd in rice.

4.
Mol Cancer ; 17(1): 5, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29325547

RESUMO

BACKGROUND: The communication between carcinoma associated fibroblasts (CAFs) and cancer cells facilitate tumor metastasis. In this study, we further underlying the epigenetic mechanisms of CAFs feed the cancer cells and the molecular mediators involved in these processes. METHODS: MCF-7 and MDA-MB-231 cells were treated with CAFs culture conditioned medium, respectively. Cytokine antibody array, enzyme-linked immunosorbent assay, western blotting and immunofluorescence were used to identify the key chemokines. Chromatin immunoprecipitation and luciferase reporter assay were performed to explore the transactivation of target LncRNA by CAFs. A series of in vitro assays was performed with RNAi-mediated knockdown to elucidate the function of LncRNA. An orthotopic mouse model of MDA-MB-231 was conducted to confirm the mechanism in vivo. RESULTS: Here we reported that TGF-ß1 was top one highest level of cytokine secreted by CAFs as revealed by cytokine antibody array. Paracrine TGF-ß1 was essential for CAFs induced EMT and metastasis in breast cancer cells, which is a crucial mediator of the interaction between stromal and cancer cells. CAF-CM significantly enhanced the HOTAIR expression to promote EMT, whereas treatment with small-molecule inhibitors of TGF-ß1 attenuated the activation of HOTAIR. Most importantly, SMAD2/3/4 directly bound the promoter site of HOTAIR, located between nucleotides -386 and -398, -440 and -452, suggesting that HOTAIR was a directly transcriptional target of SMAD2/3/4. Additionally, CAFs mediated EMT by targeting CDK5 signaling through H3K27 tri-methylation. Depletion of HOTAIR inhibited CAFs-induced tumor growth and lung metastasis in MDA-MB-231 orthotopic animal model. CONCLUSIONS: Our findings demonstrated that CAFs promoted the metastatic activity of breast cancer cells by activating the transcription of HOTAIR via TGF-ß1 secretion, supporting the pursuit of the TGF-ß1/HOTAIR axis as a target in breast cancer treatment.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Epigênese Genética , Neoplasias/genética , Neoplasias/metabolismo , Comunicação Parácrina , Animais , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Metástase Neoplásica , Neoplasias/patologia , Prognóstico , RNA Longo não Codificante/genética , Transdução de Sinais , Proteínas Smad/genética , Proteínas Smad/metabolismo , Transcrição Gênica , Fator de Crescimento Transformador beta1/metabolismo
5.
Huan Jing Ke Xue ; 39(11): 5180-5188, 2018 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628243

RESUMO

A pot experiment was carried out to investigate the effects and mechanism of particulate organic matter (POM) on cadmium uptake of rice on purple paddy soil. Organic carbon content in soil and POM and Cd content in POM and rice were analyzed. The results showed that the contents of total soil organic carbon (SOC), dissolved organic carbon (DOC), organic carbon in POM (POM-C), Cd in POM (POM-Cd), and the Cd enrichment factor in POM increased with the application of POM. When POM was applied at a rate of 2.5 g·kg-1, the proportion of POM-C and POM-Cd in soil significantly increased. Application of POM also increased rice plant biomass and enhanced the accumulation of Cd in rice. The Cd content was reduced by 24%-42% in rice roots and increased by 9%-30% in rice shoots with POM application, whereas it was reduced by 17% and 36% in rice grains when the application of POM was 0.5 g·kg-1 and 1.0 g·kg-1, respectively, but increased by 39% when the application of POM was 2.5 g·kg-1. Application of POM had no significant effect on the distribution of Cd in rice roots and shoots, but significantly affected the distribution of Cd in rice grains. The transportation of Cd from shoots to grains was inhibited at low rates of POM, but was promoted at high rates of POM, and consequently increased the Cd content in rice grains. Correlation analyses showed that the content of soil available Cd was the main factor affecting Cd accumulation in rice shoots, and the total content of POM-Cd in soil was the main factor affecting Cd accumulation in rice grains. Therefore, the addition of POM to soil could affect the Cd uptake of rice by changing the content of SOC, DOC, POM-C, POM-Cd, and available Cd in paddy soil.


Assuntos
Cádmio/farmacocinética , Oryza/metabolismo , Material Particulado , Poluentes do Solo/farmacocinética , Solo/química , Carbono/química
6.
Redox Biol ; 14: 295-304, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28987868

RESUMO

Protein kinase B (PKB/Akt) plays important roles in the regulation of lipid homeostasis, and impairment of Akt activity has been demonstrated to be involved in the development of non-alcoholic fatty liver disease (NAFLD). Previous studies suggest that cytochrome P4502E1 (CYP2E1) plays causal roles in the pathogenesis of alcoholic fatty liver (AFL). We hypothesized that Akt activity might be impaired due to CYP2E1-induced oxidative stress in chronic ethanol-induced hepatic steatosis. In this study, we found that chronic ethanol-induced hepatic steatosis was accompanied with reduced phosphorylation of Akt at Thr308 in mice liver. Chronic ethanol exposure had no effects on the protein levels of phosphatidylinositol 3 kinase (PI3K) and phosphatase and tensin homologue deleted on chromosome ten (PTEN), and led to a slight decrease of phosphoinositide-dependent protein kinase 1 (PDK-1) protein level. Ethanol exposure resulted in increased levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE)-Akt adducts, which was significantly inhibited by chlormethiazole (CMZ), an efficient CYP2E1 inhibitor. Interestingly, N-acetyl-L-cysteine (NAC) significantly attenuated chronic ethanol-induced hepatic fat accumulation and the decline of Akt phosphorylation at Thr308. In the in vitro studies, Akt phosphorylation was suppressed in CYP2E1-expressing HepG2 (CYP2E1-HepG2) cells compared with the negative control HepG2 (NC-HepG2) cells, and 4-HNE treatment led to significant decrease of Akt phosphorylation at Thr308 in wild type HepG2 cells. Lastly, pharmacological activation of Akt by insulin-like growth factor-1 (IGF-1) significantly alleviated chronic ethanol-induced fatty liver in mice. Collectively, these results indicate that CYP2E1-induced oxidative stress may be responsible for ethanol-induced suppression of Akt phosphorylation and pharmacological modulation of Akt in liver may be an effective strategy for the treatment of ethanol-induced fatty liver.


Assuntos
Citocromo P-450 CYP2E1/metabolismo , Fígado Gorduroso Alcoólico/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Doença Crônica , Fígado Gorduroso Alcoólico/patologia , Células Hep G2 , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Fosforilação
7.
Cancer Lett ; 374(1): 96-106, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-26872723

RESUMO

Carcinoma associated fibroblasts (CAFs) produce a nutrient-rich microenvironment to fuel tumor progression and metastasis. Reactive oxygen species (ROS) levels and the inflammation pathway co-operate to transform CAFs. Therefore, elucidating the mechanism mediating the activity of CAFs might identify novel therapies. Abnormal miR-21 expression was reported to be involved in the conversion of resident fibroblasts to CAFs, yet the factor that drives transformation was poorly understood. Here, we reported that high miR-21 expression was strongly associated with lymph node metastasis in breast cancer, and the activation of the miR-21/NF-кB was required for the metastatic promoting effect of CAFs. AC1MMYR2, a small molecule inhibitor of miR-21, attenuated NF-кB activity by directly targeting VHL, thereby blocking the co-precipitation of NF-кB and ß-catenin and nuclear translocation. Taxol failed to constrain the aggressive behavior of cancer cells stimulated by CAFs, whereas AC1MMYR2 plus taxol significantly suppressed tumor migration and invasion ability. Remodeling and depolarization of F-actin, decreased levels of ß-catenin and vimentin, and increased E-cadherin were also detected in the combination therapy. Furthermore, reduced levels of FAP-α and α-SMA were observed, suggesting that AC1MMYR2 was competent to reprogram CAFs via the NF-кB/miR-21/VHL axis. Strikingly, a significant reduction of tumor growth and lung metastasis was observed in the combination treated mice. Taken together, our findings identified miR-21 as a critical mediator of metastasis in breast cancer through the tumor environment. AC1MMYR2 may be translated into the clinic and developed as a more personalized and effective neoadjuvant treatment for patients to reduce metastasis and improve the chemotherapy response.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Comunicação Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Pirimidinas/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Distribuição Aleatória , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Huan Jing Ke Xue ; 37(7): 2738-2744, 2016 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964486

RESUMO

Sludge composting is an efficient way to realize the reclamation of waste sludge, while the Green House Gas (GHG) accompanying with it has raised great concern worldwide. However, we do lack the primary data in this area and a great uncertainty of the effect and GHG emission characteristics of sludge composting process in low-temperature environment also exists. This study is aiming to investigate the emission characteristics of GHG from composting in low-temperature environment by applying two different bulking agents to dewatered urban sludge. The results showed that aerobic composting could go smoothly even in an environment with lower temperature, yet the maturity was low due to a sharp drop of pile temperature at the stage of maturing. Sawdust treatment could reduce the total nitrogen loss compared with cornstalk treatment, while its GHG emission equivalence was higher (169.45 and 133.13 kg·t-1 dry sludge, respectively). The accumulative CH4 emissions of sawdust and cornstalk were 0.648 and 0.689 kg·t-1 dry sludge, respectively, of which over 75% was from the first two weeks; total N2O emissions of sawdust and cornstalk were 0.486 and 0.365 kg·t-1 dry sludge, of which more than 90% came from the decomposting process. On the whole, because of the relatively short duration of high temperature as well as the low temperature during mature stage, the process had an especially low emission of CH4 but a relatively high discharge of N2O. For composting in low-temperature environment, necessary measures should be taken to control N2O emission in the late period in order to realize GHG reduction.


Assuntos
Compostagem , Gases de Efeito Estufa/análise , Esgotos/química , Nitrogênio , Estações do Ano
9.
Exp Mol Pathol ; 99(3): 524-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26341138

RESUMO

Epithelial-mesenchymal transition (EMT) is regulated by multiple signal transduction pathways. Twist-1 is one of the most important transcription factors in these pathways. In a previous study, we found that Bcl-2 enhanced the role of Twist-1 in EMT. Coexpression of Twist-1 and Bcl-2 may play an import role in vasculogenic mimicry (VM) through regulation of EMT. Moreover, regulators of EMT and VM are known to be important targets for microRNAs (miRNAs). To better understand how these critical pathways are induced by coexpression of Twist-1 and Bcl-2, we performed a comprehensive comparative bioinformatics analysis using microarrays on HCCs that overexpressed Twist-1 and Bcl-2. Eleven miRNAs associated with coexpression of Twist-1 and Bcl-2 were selected from the comprehensive analysis of miRNA microarray and ChIP-seq analysis. Changes in miRNAs were associated with significant differences in the expression of genes involved in signal transduction pathways related to processes including tumor invasion, metastasis, angiogenesis, and tumor cell shape. We confirmed the role of Twist-1 and Bcl-2 coexpression in HCC cells using wound healing assays, invasion assays, and 3D Matrigel assays. Furthermore, the role of miR-27a as a crucial regulator of EMT and VM was confirmed in HCC cells by RT-PCR and western blot analysis. These findings provide evidence that Bcl-2 enhances the role of Twist-1 in VM and EMT through miRNAs.


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Proteína 1 Relacionada a Twist/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Humanos , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo
10.
Int J Biol Sci ; 11(6): 643-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25999787

RESUMO

To explore the underlying mechanisms for the protective effects of garlic oil (GO) against nitrosodiethylamine (NDEA)-induced hepatocarcinoma, 60 male Wistar rats were randomized into 4 groups (n=15): control group, NDEA group, and two GO plus NDEA groups. The rats in GO plus NDEA groups were pretreated with GO (20 or 40 mg/kg) for 7 days. Then, all rats except those in control group were gavaged with NDEA for 20 weeks, and the rats in GO plus NDEA groups were continuously administered with GO. The results showed that GO co-treatment significantly suppressed the NDEA-induced increases of alpha fetal protein (AFP) level in serum, nuclear atypia in H&E staining, sirius red-positive areas and proliferating cell nuclear antigen (PCNA) expression. The molecular mechanisms exploration revealed that the protein levels of phosphatidylinositol 3 kinase (PI3K)-p85, PI3K-p110, total AKT, p-AKT (Ser473) and p-AKT (Thr308) in the liver of NDEA group rats were higher than those in control group rats. In addition, NDEA treatment induced IκB degradation and NF-κB p65 phosphorylation, and up-regulated the protein levels of downstream pro-inflammatory mediators. GO co-treatment significantly reversed all the above adverse effects induced by NDEA. These results suggested that the protective effects of GO against NDEA-induced hepatocarcinoma might be associated with the suppression of PI3K- AKT-NF-κB pathway.


Assuntos
Compostos Alílicos/farmacologia , Carcinoma/induzido quimicamente , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas/induzido quimicamente , Substâncias Protetoras/farmacologia , Sulfetos/farmacologia , alfa-Fetoproteínas/metabolismo , Animais , Ciclo-Oxigenase 2/metabolismo , Proteínas I-kappa B/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Int J Clin Exp Pathol ; 8(12): 15759-68, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26884845

RESUMO

OBJECTIVE: An investigation of the role of the anti-apoptotic protein Bcl-2 and its associated miRNAs in vasculogenic mimicry (VM) in hepatocellular carcinoma. METHODS: The Bcl-2 expression plasmid was constructed for transfection into the hepatocellular carcinoma cell line HepG2. Changes in the expression profiles of the miRNAs induced by Bcl-2 overexpression and their relationships with vasculogenic mimicry were analysed. Real-time PCR was performed in frozen tissue specimens from 42 cases of hepatocellular carcinoma to analyse the relationship between Bcl-2 and miR-27a; Immunohistochemical staining was performed in paraffin-embedded tissue samples from 97 cases of hepatocellular carcinoma to analyse the relationship between Bcl-2 expression and the expression of vasculogenic mimicry (VM) related molecules VEGF and HIF1A, which were target genes of the Bcl-2 related miRNAs. RESULTS: Overexpression of Bcl-2 results in a significant change in the expression of a wide range of miRNAs, and the target genes of these miRNAs are composed of various vasculogenic mimicry related genes; Bcl-2 expression was positively correlated with the expression of the miRNA target genes VEGF and HIF1A. The expression of VEGF and HIF1A was significantly and positively correlated with VM and poor prognosis of patients. CONCLUSION: Bcl-2 may play a role in vasculogenic mimicry through miRNAs by targeting angiogenesis associated genes.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Mimetismo Molecular , Neovascularização Patológica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Transdução de Sinais , Transfecção , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Chem Biol Interact ; 222: 18-26, 2014 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-25162931

RESUMO

Cytochrome P4502E1 (CYP2E1) has been demonstrated to play crucial roles in chronic ethanol-induced fatty liver, while its role in acute ethanol-induced fatty liver remains unclear. The current study was designed to evaluate the effects of chlormethiazole (CMZ), a specific inhibitor of CYP2E1, on acute ethanol-induced fatty liver, and to explore the mechanisms. Mice were pretreated with single dose of CMZ (50mg/kg body weight) by intraperitoneal injection or equal volume of saline, and then exposed to three doses of ethanol (5g/kg body weight, 25%, w/v) by gavage with 12h intervals. The mice were sacrificed at 4h after the last ethanol dosing. It was found that CMZ significantly attenuated acute ethanol-induced increase of the hepatic and serum triglyceride levels, and reduced fat droplets accumulation in mice liver. Acute ethanol-induced increase of the hepatic malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) levels (two biomarkers for oxidative stress) and decrease of glutathione (GSH) level was significantly suppressed by CMZ. CMZ also suppressed ethanol-induced decline of serum adiponectin level, but did not significantly affect the serum tumor necrosis factor-α (TNF-α) and ethanol levels. Furthermore, a significant decline of p62 protein level was observed in CMZ/ethanol group mice liver compared with that of the ethanol group mice. However, acute ethanol-induced increase of peroxisome proliferator-activated receptor α (PPAR-α) protein level was suppressed by CMZ, while the protein levels of sterol regulatory element-binding protein-1c (SREBP-1) and diacylglycerol acyltransferase 2 (DGAT2) were not significantly affected by ethanol or CMZ. Collectively, the results of the current study demonstrated that CMZ could effectively attenuate acute ethanol-induced fatty liver possibly by suppressing oxidative stress and adiponectin decline, and activating autophagy, which suggest that CYP2E1 might also play important roles in acute ethanol-induced fatty liver.


Assuntos
Clormetiazol/farmacologia , Inibidores do Citocromo P-450 CYP2E1/farmacologia , Fígado Gorduroso Alcoólico/prevenção & controle , Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/sangue , Animais , Autofagia/efeitos dos fármacos , Carbono-Carbono Ligases/metabolismo , Diacilglicerol O-Aciltransferase/metabolismo , Modelos Animais de Doenças , Ácido Graxo Sintases/metabolismo , Fígado Gorduroso Alcoólico/metabolismo , Fígado Gorduroso Alcoólico/patologia , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , PPAR alfa/genética , PPAR alfa/metabolismo , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
13.
Asian Pac J Cancer Prev ; 15(12): 4893-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24998559

RESUMO

BACKGROUND: Recent reports have shown that C-X-C chemokine receptor 4 (CXCR4) plays an important role in metastasis. Despite a clear understanding of the protein's structure and properties, its functional role remains elusive. We conducted the present study to evaluate the expressions of CXCR4 in pancreatic cancer, and to investigate its relationship with clinicopathological parameters, especially perineural invasion(PNI). MATERIALS AND METHODS: The association between CXCR4 expression and perineural invasion was determined by immunohistochemistry in pancreatic cancer patients (n=51). RESULTS: CXCR4 expression was correlated with the existence of PNI and the type of PNI (p=0.042, p=0.040). TIMP-2 expression was also correlated with the existence, the pathway and degree of PNI (p=0.000, p=0.006, p=0.000). CONCLUSIONS: Our results suggest an association between PNI and expression of CXCR4 and TIMP-2 in pancreatic cancer. CXCR4 may promote the occurrence of PNI in pancreatic cancer cells by decreasing the inhibition of TIMPs on MMP.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/secundário , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Nervos Periféricos/patologia , Receptores CXCR4/metabolismo , Adulto , Idoso , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Nervos Periféricos/metabolismo , Prognóstico
14.
PLoS One ; 9(6): e98658, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24892905

RESUMO

BACKGROUND: Cytochrome P4502E1 (CYP2E1) has been suggested to play critical roles in the pathogenesis of alcoholic fatty liver (AFL), but the underlying mechanisms remains unclear. The current study was designed to evaluate whether CYP2E1 suppression by chlormethiazole (CMZ) could suppress AFL in mice, and to explore the underlying mechanisms. METHODS: Mice were treated with or without CMZ (50 mg/kg bw, i.p.) and subjected to liquid diet with or without ethanol (5%, w/v) for 4 weeks. Biochemical parameters were measured using commercial kits. The protein and mRNA levels were detected by western blot and qPCR, respectively. Histopathology and immunohistochemical assay were performed with routine methods. RESULTS: CYP2E1 inhibition by CMZ completely blocked AFL in mice, shown as the decline of the hepatic and serum triglyceride levels, and the fewer fat droplets in the liver sections. Chronic ethanol exposure led to significant decrease of the mRNA and protein levels of peroxisome proliferator-activated receptor α (PPAR-α), which was blocked by CMZ co-treatment. CMZ co-treatment suppressed ethanol-induced oxidative stress, overproduction of tumor necrosis α (TNF-α), and decrease of protein levels of the PPAR-α co-activators including p300 and deacetylated PGC1-α. Furthermore, CMZ co-treatment led to the activation of AMP-activated protein kinase (AMPK), mitogen-activated protein kinase (MAPK), and PI3K/Akt/GSK3ß pathway. However, chronic ethanol-induced decline of acyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) protein levels was partially restored by CMZ, while the activation of autophagy appeared to be suppressed by CMZ. CONCLUSION: These results suggested that CMZ suppressed chronic ethanol-induced oxidative stress, TNF-α overproduction, decline of p300 protein level and deacetylation of PGC1-α, and activated AMPK, MAPK, and PI3K/Akt/GSK3ß pathway, which might contribute to the activation of PPAR-α and account for the protection of CMZ against AFL.


Assuntos
Etanol/toxicidade , Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estresse Oxidativo/efeitos dos fármacos , PPAR alfa/metabolismo , Fatores de Transcrição/metabolismo , Acetilação/efeitos dos fármacos , Animais , Clormetiazol/uso terapêutico , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/tratamento farmacológico , Glicogênio Sintase Quinase 3 beta , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Transdução de Sinais/efeitos dos fármacos
15.
Eur J Gastroenterol Hepatol ; 26(6): 646-53, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24743504

RESUMO

AIMS: Pentoxifylline has been used to treat nonalcoholic fatty liver diseases (NAFLDs) due to its anti-tumor necrosis factor-α effects. We conducted a meta-analysis of randomized, double-blinded, placebo-controlled trials to investigate the effect of pentoxifylline on the biochemical and histological parameters of NAFLD patients. MATERIALS AND METHODS: A comprehensive literature search was conducted in the database including PubMed, Embase, ISI web of knowledge, the Cochrane Library, and Google Scholar to identify randomized, double-blind, placebo-controlled clinical trials about the effects of pentoxifylline on NAFLD. The pooled weighted mean difference (WMD) with 95% confidence interval (CI) was calculated to compare the effects of pentoxifylline and placebo. RESULTS: Five well-designed studies were retrieved. Pooled results showed that pentoxifylline significantly reduced the serum alanine transaminase activity (WMD=-27.97; 95% CI: -42.59, -13.34) and aspartate transaminase activity (WMD=-13.97; 95% CI: -23.31, -4.63) in NAFLD patients compared with placebo. In addition, pentoxifylline significantly improved steatosis (WMD=-0.68; 95% CI: -1.01, -0.34), lobular inflammation (WMD=-0.49; 95% CI: -0.86, -0.12), and fibrosis (WMD=-0.60; 95% CI: -0.99, -0.21). Furthermore, pentoxifylline also led to significant reduction in BMI (WMD=-0.51; 95% CI: -0.96, -0.06) and fasting glucose (WMD=-8.97; 95% CI: -14.52, -3.42), but did not significantly affect the serum tumor necrosis factor α and adiponectin levels when compared with placebo. CONCLUSION: Pentoxifylline could reduce the aminotransferase activities and improve the histological parameters in NAFLD patients. Large well-designed, randomized, placebo-controlled studies are needed to confirm these results.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Pentoxifilina/uso terapêutico , Anti-Inflamatórios não Esteroides/efeitos adversos , Método Duplo-Cego , Humanos , Pentoxifilina/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Transaminases/sangue , Fator de Necrose Tumoral alfa/antagonistas & inibidores
16.
Artigo em Chinês | MEDLINE | ID: mdl-24370287

RESUMO

OBJECTIVE: To investigate the protective effects of docosahexaenoic acid (DHA) and nervonic acid (NA) on the learning and memory abilities in rats exposed to 1-bromopropane (1-BP) and their action mechanisms. METHODS: Forty male Wistar rats (specific pathogen-free) were randomly divided into 4 groups (n = 10 for each), i.e., solvent control group, 1-BP (800 mg/kg) group, NA (150 mg/kg) + 1-BP (800 mg/kg) group, and DHA (500 mg/kg) + 1-BP (800 mg/kg) group. The rats were given respective test substances by gavage for 7 d. The Morris water maze (MWM) test was performed from days 8 to 12 to evaluate the rats' learning and memory abilities. After MWM test, rats were sacrificed in the next day, and cerebral cortex was quickly dissected and homogenized in an ice bath. The supernatant of the obtained homogenate was collected to measure the content of glutathione (GSH) and malondialdehyde (MDA) and the activities of glutathione reductase (GR) and γ-glutamate cysteine ligase (γ-GCL). RESULTS: The MWM spatial navigation test showed that the 1-BP group had significantly longer escape latency and significantly longer total swimming distance compared with the control group (P<0.05), while the DHA+1-BP group had significant decreases in escape latency and total swimming distance compared with the 1-BP group (P<0.05). The spatial probe test showed that the number of platform crossings was significantly greater in the DHA+1-BP group and NA+1-BP group than in the 1-BP group (P<0.05); compared with the control group, the 1-BP group had a significantly lower ratio of time spent in the zone around the platform to total time (P < 0.05), and the ratio was significantly higher in the DHA+1-BP group than in the 1-BP group (P < 0.05). Compared with the control group, the 1-BP group had a 18.1% decrease in GSH content, and DHA could significantly reverse 1-BP-induced decrease in GSH content (P < 0.05). Compared with the 1-BP group, the DHA+1-BP group and NA+1-BP group had significantly decreased MDA content (P < 0.05), the DHA+1-BP group had significantly increased GR activity (P < 0.05), and the NA+1-BP group had significantly increased γ-GCL activity (P < 0.05). CONCLUSION: The rats exposed to 1-BP have oxidative stress in the brain and impaired cognitive function. DHA and NA can reduce 1-BP-induced cognitive function impairment in rats, possibly by increasing the activities of GR and γ-GCL and the content of GSH in the brain.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Animais , Comportamento Animal , Encéfalo/efeitos dos fármacos , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Hidrocarbonetos Bromados/toxicidade , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo , Ratos , Ratos Wistar
17.
J Food Sci ; 78(6): H936-42, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23772706

RESUMO

Although the anticancer effects of garlic and its products have been demonstrated by a variety of studies; however, few studies were conducted to investigate the effects of garlic on the adverse effects of chemo/radiotherapy. In order to clarify the above question and make a more comprehensive understanding of the anticancer effects of garlic, tumor xenograft mice model was established by subcutaneous injection of H22 tumor cells, and was used for the investigation of effects of garlic oil (GO) on the chemo/radiotherapy. In the chemotherapy test, tumor-bearing mice were treated with cyclophosphamide (CTX) or CTX plus GO (25 or 50 mg/kg bw) for 14 d, while the mice received a single 5 Gy total body radiation or radiation plus GO (25 or 50 mg/kg bw) in radiotherapy test. The results showed that GO did not increase the tumor inhibitory rate of CTX/radiation, which indicated that GO could not enhance the chemo/radiosensitivity of cancer cells. However, the decrease of the peripheral total white blood cells (WBCs) count induced by CTX/radiation was significantly suppressed by GO cotreatment. Furthermore, GO cotreatment significantly inhibited the decrease of the DNA contents and the micronuclei ratio of the bone marrow. Lastly, the reduction of the endogenous spleen colonies induced by CTX/radiation was significantly suppressed by GO cotreatment. These findings support the idea that GO consumption may benefit for the cancer patients receiving chemotherapy or radiotherapy.


Assuntos
Compostos Alílicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Alho/química , Doenças Hematológicas/tratamento farmacológico , Óleos de Plantas/farmacologia , Sulfetos/farmacologia , Animais , Antineoplásicos , Linhagem Celular Tumoral , Ensaio de Unidades Formadoras de Colônias , Ciclofosfamida/efeitos adversos , Modelos Animais de Doenças , Doenças Hematológicas/etiologia , Masculino , Camundongos , Testes para Micronúcleos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Baço/citologia , Baço/metabolismo
18.
Melanoma Res ; 23(4): 243-53, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23695439

RESUMO

Melanoma is the least common but most serious form of skin cancer. The leading cause of death in melanoma patients is widespread metastasis caused by increased cell motility and a rich blood supply for tumor cells. A unique form of microcirculation called vasculogenic mimicry, which efficiently supplies blood to tumor cells, has been reported recently. Apoptosis-related protein performs a nonapoptotic function to promote migration and invasion of tumor cells. This study focuses on the nonapoptotic role of caspase-3 in melanoma and its effects on the migration, invasion, and vasculogenic mimicry formation of melanoma cells. Human melanoma samples were used to detect active caspase-3 expression and determine its relationship with clinicopathologic parameters. In addition, a human melanoma A375 cell line was used to determine the role of caspase-3 in migration and invasion using z-DEVD-fmk, a selective caspase-3 inhibitor, to inhibit caspase-3 activity. The findings suggest that active caspase-3 is expressed in nonapoptotic melanoma cells and is related to metastasis and vasculogenic mimicry formation in patients with melanoma. Low doses of caspase-3 inhibitor reduced caspase-3 activity without affecting cell apoptosis. Inhibition of caspase-3 activity using low-dose z-DEVD-fmk decreased the migration, invasion, and vasculogenic mimicry formation of melanoma cells in vitro. Similarly, downregulation of caspase-3 by specific small interfering RNA also inhibited the migratory, invasive, and tube-forming potential of melanoma cells. The caspase-3-mediated promotion of melanoma cell motility may be because of the cleavage of matrix metalloproteinase-2.


Assuntos
Caspase 3/metabolismo , Adesão Celular , Movimento Celular , Proliferação de Células , Melanoma/patologia , Neovascularização Patológica/patologia , Animais , Apoptose , Western Blotting , Citometria de Fluxo , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Melanoma/genética , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Neovascularização Patológica/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Células Tumorais Cultivadas
19.
Int J Biol Sci ; 9(3): 237-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23494807

RESUMO

Nitrosodiethylamine (NDEA) is a potent carcinogen widely existing in the environment. Our previous study has demonstrated that garlic oil (GO) could prevent NDEA-induced hepatocarcinogenesis in rats, but the underlying mechanisms are not fully understood. It has been well documented that the metabolic activation may play important roles in NDEA-induced hepatocarcinogenesis. Therefore, we designed the current study to explore the potential mechanisms by investigating the changes of hepatic phase Ⅰ enzymes (including cytochrome P450 enzyme (CYP) 2E1, CYP1A2 and CYP1A1) and phase Ⅱ enzymes (including glutathione S transferases (GSTs) and UDP- Glucuronosyltransferases (UGTs)) by using enzymatic methods, real-time PCR, and western blotting analysis. We found that NDEA treatment resulted in significant decreases of the activities of CYP2E1, CYP1A2, GST alpha, GST mu, UGTs and increases of the activities of CYP1A1 and GST pi. Furthermore, the mRNA and protein levels of CYP2E1, CYP1A2, GST alpha, GST mu and UGT1A6 in the liver of NDEA-treated rats were significantly decreased compared with those of the control group rats, while the mRNA and protein levels of CYP1A1 and GST pi were dramatically increased. Interestingly, all these adverse effects induced by NDEA were simultaneously and significantly suppressed by GO co-treatment. These data suggest that the protective effects of GO against NDEA-induced hepatocarcinogenesis might be, at least partially, attributed to the modulation of phase I and phase II enzymes.


Assuntos
Compostos Alílicos/farmacologia , Biotransformação/efeitos dos fármacos , Carcinógenos Ambientais/toxicidade , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/prevenção & controle , Sulfetos/farmacologia , Animais , Carcinógenos Ambientais/farmacocinética , Transformação Celular Neoplásica/induzido quimicamente , Sistema Enzimático do Citocromo P-450/metabolismo , Dietilnitrosamina/farmacocinética , Glutationa Transferase/metabolismo , Inativação Metabólica , Fígado/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
20.
Med Oncol ; 29(5): 3599-607, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22562824

RESUMO

Vasculogenic mimicry (VM) refers to the unique ability of highly aggressive tumor cells to mimic the pattern of embryonic vasculogenic networks. Hypoxia plays a pivotal role in the formation of VM. Hypoxia-induced Bcl-2 overexpression is observed in many types of tumors including melanoma, in which it is associated with tumorigenicity and angiogenesis. VE-cadherin, the major endothelial adhesion molecule controlling cellular junctions and blood vessel formation, is also overexpressed in melanoma. Despite these connections, whether hypoxia induces VM formation via VE-cadherin regulation by Bcl-2 is not confirmed. We used human melanoma cells to upregulate or knockdown the expression of Bcl-2 to investigate the possible molecular mechanism of VM formation under hypoxia. Bcl-2 overexpression increased VE-cadherin expression and VM formation under normoxia, whereas Bcl-2 siRNA significantly decreased VE-cadherin expression and VM formation under hypoxia. We then demonstrated that Bcl-2 regulated VE-cadherin transcription activity by Western blot, three-dimensional cultures, reporter gene assay, and clinical analysis. Therefore, Bcl-2-dependent VE-cadherin overexpression may be an important mechanism by which hypoxia induces VM.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Hipóxia Celular/fisiologia , Melanoma/metabolismo , Mimetismo Molecular/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Vasos Sanguíneos , Western Blotting , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Melanoma/patologia
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