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1.
Sci Total Environ ; 891: 164516, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37263437

RESUMO

In order to explain reasons why flue-gas CO2 (normally containing high CO2) enhanced carbon fixation and lipids synthesis with increased photochemical electron production in microalgae cells. Focused ion beam scanning electron microscopy (FIB-SEM) was combined with proteomics and phosphorylation modification mics to clarify mechanisms of lipids synthesis at protein and organelle levels in Chlorella pyrenoidosa cells cultivated with high CO2 concentration (15 % v/v). The volumes of chloroplast and endoplasmic reticulum in subcellular organelles increased by 47 % and 306 %, respectively, compared with the control, which improved conversion efficiency of starch grains to lipids (lipid content increased by 57 %). Proteomics and modifications omics revealed that protein translation and ribosome structure and biogenesis-related enzymes were significantly modified by phosphorylation, which regulated protein biological functions. Glycolysis, pentose phosphate pathway and other carbohydrate metabolic pathways were markedly enriched and promoted the expression of lipid synthase, which was consistent with enhanced carbon fixation in photosynthesis, expansion of subcellular organelles and improved lipids synthesis.


Assuntos
Chlorella , Microalgas , Chlorella/metabolismo , Proteômica , Dióxido de Carbono/metabolismo , Lipídeos , Organelas/metabolismo , Microalgas/metabolismo , Biomassa
2.
Sci Total Environ ; 883: 163318, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37030370

RESUMO

To determine the optimal CO2 concentration for microalgal biomass cultivated with industrial flue gas and improve carbon fixation capacity and biomass production. Functional metabolism pathways of significantly regulated genes in Nannochloropsis oceanica (N. oceanica) with various nitrogen/phosphorus (N/P) nutrients for CO2 fixation were comprehensively clarified. At 100 % N/P nutrients, the optimum CO2 concentration was 70 % and the maximum biomass production of microalgae was 1.57 g/L. The optimum CO2 concentration was 50 % for N or P deficiency and 30 % for both N and P deficiency. The optimal combination of CO2 concentration and N/P nutrients caused significant up regulation of proteins related to photosynthesis and cellular respiration in the microalgae, enhancing photosynthetic electron transfer efficiency and carbon metabolism. Microalgal cells with P deficiency and optimal CO2 concentration expressed many phosphate transporter proteins to enhance P metabolism and N metabolism to maintain a high carbon fixation capacity. However, inappropriate combination of N/P nutrients and CO2 concentrations caused more errors in DNA replication and protein synthesis, generating more lysosomes and phagosomes. This inhibited carbon fixation and biomass production in the microalgae with increased cell apoptosis.


Assuntos
Microalgas , Estramenópilas , Dióxido de Carbono/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Fotossíntese , Nutrientes , Microalgas/metabolismo , Estramenópilas/metabolismo , Biomassa
3.
Cells ; 12(6)2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36980207

RESUMO

The toxicity and side effects of chemotherapeutic drugs remain a crucial obstacle to the clinical treatment of hepatocellular carcinoma (HCC). Identifying combination therapy from Chinese herbs to enhance the sensitivity of tumors to chemotherapeutic drugs is of particular interest. Astragalus polysaccharide (APS), one of the natural active components in Astragalus membranaceus, has been reported to exhibit anti-tumor properties in diverse cancer cell lines. The aim of this study was to determine the effect of APS on Doxorubicin (Dox)-induced apoptosis in HCC and the underlying mechanism. The results showed that APS dose-dependently promoted Dox-induced apoptosis and enhanced endoplasmic reticulum (ER) stress. Additionally, APS decreased the mRNA level and protein stability of O-GlcNAc transferase (OGT), and increased the O-GlcNAcase (OGA) expression. Furthermore, OGT lentiviral transfection or PugNAc (OGA inhibitor) treatment reversed the ER stress and apoptosis induced by the combination of Dox and APS. A xenograft tumor mouse model confirmed that the combination of APS and Dox showed an advantage in inhibiting tumor growth in vivo. These findings suggested that APS promoted Dox-induced apoptosis in HCC cells through reducing the O-GlcNAcylation, which led to the exacerbation of ER stress and activation of apoptotic pathways.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Camundongos , Animais , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Doxorrubicina/farmacologia , Modelos Animais de Doenças , Apoptose , Polissacarídeos/farmacologia
4.
Pharmacol Res ; 178: 106180, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35288308

RESUMO

Metastasis remains a crucial obstacle to the clinical treatment of hepatocellular carcinoma (HCC). Investigating the potential anti-tumor compounds from medicinal herb against HCC metastasis is of particular interest. As a triterpenoid saponin, α-Hederin has been reported to exhibit cytotoxicity for diverse cancer cell lines by inducing mitochondrial related apoptosis or autophagic cell death. Nevertheless, little is known about the inhibitory effect of α-Hederin on the metastasis of HCC and its underlying mechanisms. Here, we integrated well-established target prediction webtool and molecular docking methods to predict the potential targets for α-Hederin, and finally focused on PTAFR, the receptor for platelet-activating factor (PAF). Activation of PAF/PTAFR pathways has been reported to be contribution to the initiation and progression of cancer. We showed for the first time that non-cytotoxic concentration of α-Hederin inhibited cell migration and invasion induced by PAF in HCC cells, as well as lung metastasis in vivo. Moreover, we demonstrated α-Hederin reduced the PAF-induced matrix metalloproteinase-2 expression through inhibiting the activation of STAT3 in PAF stimulated HCC cells. These findings suggest that α-Hederin functions as a prospective inhibitor of PTAFR and may be utilized as an optional candidate for treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Metaloproteinase 2 da Matriz , Ácido Oleanólico , Fator de Ativação de Plaquetas , Saponinas , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metaloproteinase 2 da Matriz/metabolismo , Simulação de Acoplamento Molecular , Metástase Neoplásica , Ácido Oleanólico/farmacologia , Fator de Ativação de Plaquetas/antagonistas & inibidores , Fator de Ativação de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Fator de Transcrição STAT3 , Saponinas/farmacologia , Transdução de Sinais/efeitos dos fármacos
5.
Bioresour Technol ; 345: 126479, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34864173

RESUMO

In order to optimize light distribution for promoting biomass growth rate of Chlorella pyrenoidosa, concave walls were installed in plate photobioreactors (PBR) to generate rotational flow field of microalgal solution circulated from top inlets to bottom outlets. Flow vortices in four corners of concave-wall PBR resulted in decreased mixing time and increased mass transfer coefficient. The CO2 bio-fixation by C. pyrenoidosa increased by 27% and chlorophyll-a concentration enhanced by 18.5% in concave-wall PBR compared to those in control (flat-wall) PBR. The concave walls diverge light rays to enhance frontal light exposure and supply more light photons into interior regions of PBRs. The promotion in light distribution and vortex flow field with concave walls enhanced light and nutrients utilization by microalgal cells, leading to an increased biomass growth rate by 21%.


Assuntos
Chlorella , Microalgas , Biomassa , Luz , Fotobiorreatores
6.
J Ethnopharmacol ; 266: 113446, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33031902

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hepatocellular carcinoma (HCC) is an aggressive malignancy with increasing mortality in China. Screening and identifying effective anticancer compounds from active traditional Chinese herbs for HCC are in demand. Akebia trifoliata (Thunb) Koidz, with pharmacological anti-HCC activities in clinical, has been shown in previous research. In the present research, we elucidated a potential anticancer effect of Akebia saponin E (ASE), which is isolated from the immature seeds of Akebia trifoliata (Thunb.) Koidz, and revealed that ASE could induce severe expanded vacuoles in HCC cells. But the potential mechanism of vacuole-formation and the anti-HCC effects by ASE remain uncover. AIM OF THIS STUDY: To elucidate the potential mechanism of vacuole-formation and the proliferation inhibition effects by ASE in HCC cell lines. MATERIALS AND METHODS: MTT assay, colony formation assay and flow cytometry were performed to detect cell viability. Immunofluorescence analysis was used to examine the biomarkers of endomembrane. Cells were infected with tandem mRFP-GFP-LC3 lentivirus to assess autophagy flux. RNA-seq was conducted to analyze the genome-wide transcriptional between treatment cell groups. In vitro PIKfyve kinase assay is detected by the ADP-GloTM Kinase Assay Kit. RESULTS: ASE could inhibit the proliferation of HCC with severe expanded vacuoles in vitro, and could significantly reduce the size and weight of xenograft tumor in vivo. Further, the vacuoles induced by ASE were aberrant enlarged lysosomes instead of autophagosome or autolysosomes. With cytoplasmic vacuolation, ASE induced a mTOR-independent TFEB activation for lysosomal biogenesis and a decrement of cholesterol levels in HCC cells. Furthermore, ASE could reduce the activity of PIKfyve (phosphoinositide kinase containing a FYVE-type finger), causing aberrant lysosomal biogenesis and cholesterol dyshomeostasis which triggered the expanded vacuole formation. CONCLUSION: ASE can prospectively inhibit the kinase activity of PIKfyve to induce lysosome-associated cytoplasmic vacuolation, and may be utilized as an alternative candidate to treat human HCC.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Ranunculales/química , Saponinas/farmacologia , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase/isolamento & purificação , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Saponinas/isolamento & purificação , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Ethnopharmacol ; 234: 204-215, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30528882

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The high recurrence rate postoperative and extensive metastases have become the obstacle of Hepatocellular Carcinoma (HCC) efficacy improvements, which contribute to most of the patient mortality. Akebia trifoliata (Thunb.) Koidz has been shown pharmacological activities in clinical and anti-HCC biological activity in previous research, but its potential function of anti-metastasis remains unknown. AIM OF THIS STUDY: To make sure whether ATKSE inhibits migration and invasion in HCC cell lines in vitro and the potential mechanism. MATERIALS AND METHODS: A UHPLC-HRMS analysis was adopted to identify and control the quality of the ethanol extract of Akebia trifoliata (Thunb.) Koidz Seed (abbreviated ATKSE). Cell viability of three kinds of HCC cell lines (HEPG2, HUH7, and SMMC7721) was detected using MTT assay and Flow cytometry. Adhesion capacity was measured by cell-matrigel adhesion assay. Wounded healing and Matrigel-transwell invasion assays were performed to assess cell migration and invasion, respectively. Western blot assay was used to detect several metastasis-related protein molecules, including FAK adhesion signaling, cadherin molecules, and MMPs. ELISA assay was used to evaluate the secreted MMP9 level. RESULTS: ATKSE significantly suppressed HCC cells viability and proliferation (from 0.9 up to 3.0 mg/ml); then under sub-lethal concentration (from 0.25 up to 1.0 mg/ml), ATKSE inhibited cell adhesion, migration, and invasion in a way of dose-dependent. Several metastatic-related molecules or pathway, including FAK adhesion signaling, cadherin molecules, and MMPs, took part in this process. There are both differences and commonalities in various cell lines: typically such as p-FAK was down-regulated by ATKSE in both HEPG2 and SMMC7721, while was raised in HUH7; Further attempts on the combination of ATKSE and FAK inhibitors, provide us with the enhanced inhibitory effects of invasion and migration in HEPG2 and HUH7 cells, as well as antagonistic effects in SMMC7721. As a target or potential mechanism, it may be more valuable to concern FAK inhibition by ATKSE in HEPG2 cells than in the other two cells. CONCLUSIONS: These results suggest that ATKSE has anti-metastasis potency in HCC cells.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Magnoliopsida/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/patologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Espectrometria de Massas/métodos , Invasividade Neoplásica/prevenção & controle , Extratos Vegetais/administração & dosagem , Sementes
8.
J Hepatol ; 68(6): 1191-1202, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29454068

RESUMO

BACKGROUND & AIMS: Aberrant oncogenic mRNA translation and protein O-linked ß-N-acetylglucosaminylation (O-GlcNAcylation) are general features during tumorigenesis. Nevertheless, whether and how these two pathways are interlinked remain unknown. Our previous study indicated that ribosomal receptor for activated C-kinase 1 (RACK1) promoted chemoresistance and growth in hepatocellular carcinoma (HCC). The aim of this study is to examine the role of RACK1 O-GlcNAcylation in oncogene translation and HCC carcinogenesis. METHODS: The site(s) of RACK1 for O-GlcNAcylation was mapped by mass spectrometry analysis. HCC cell lines were employed to examine the effects of RACK1 O-GlcNAcylation on the translation of oncogenic factors and behaviors of tumor cells in vitro. Transgenic knock-in mice were used to detect the role of RACK1 O-GlcNAcylation in modulating HCC tumorigenesis in vivo. The correlation of RACK1 O-GlcNAcylation with tumor progression and relapse were analyzed in clinical HCC samples. RESULTS: We found that ribosomal RACK1 was highly modified by O-GlcNAc at Ser122. O-GlcNAcylation of RACK1 enhanced its protein stability, ribosome binding and interaction with PKCßII (PRKCB), leading to increased eukaryotic translation initiation factor 4E phosphorylation and translation of potent oncogenes in HCC cells. Genetic ablation of RACK1 O-GlcNAcylation at Ser122 dramatically suppressed tumorigenesis, angiogenesis, and metastasis in vitro and in diethylnitrosamine (DEN)-induced HCC mouse model. Increased RACK1 O-GlcNAcylation was also observed in HCC patient samples and correlated with tumor development and recurrence after chemotherapy. CONCLUSIONS: These findings demonstrate that RACK1 acts as key mediator linking O-GlcNAc metabolism to cap-dependent translation during HCC tumorigenesis. Targeting RACK1 O-GlcNAcylation provides promising options for HCC treatment. LAY SUMMARY: O-GlcNAcylation of ribosomal receptor for activated C-kinase 1 at the amino acid serine122 promotes its stability, ribosome localization and interaction with the protein kinase, PKCßII, thus driving the translation of oncogenes and tumorigenesis of hepatocellular carcinoma. Increased O-GlcNAcylation of ribosomal receptor for activated C-kinase 1 is positively correlated with tumor growth, metastasis and recurrence in patients with hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/etiologia , Neoplasias Hepáticas/etiologia , Proteínas de Neoplasias/metabolismo , Receptores de Quinase C Ativada/metabolismo , Substituição de Aminoácidos , Animais , Carcinógenos/química , Carcinógenos/metabolismo , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Glicosilação , Humanos , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Camundongos Nus , Camundongos Transgênicos , Mutagênese Sítio-Dirigida , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Proteína Quinase C beta/metabolismo , Estabilidade Proteica , Receptores de Quinase C Ativada/química , Receptores de Quinase C Ativada/genética , Serina/química
9.
Oncotarget ; 8(12): 19205-19217, 2017 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-28186970

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. As a branch of glucose metabolism, hexosamine biosynthesis pathway (HBP) has been reported to play a critical role in the insulin resistance and progression of cancer. Glutamine:fructose-6-phosphate amidotransferase (GFAT) is the rate-limiting enzyme of the HBP; nevertheless, the prognostic value of GFAT1 in HCC remains elusive. In this study, we found that high expression of GFAT1 was significantly associated with serum alpha-fetoprotein (AFP), serum alanine aminotransferase (ALT), tumor size, tumor encapsulation, T stage and TNM stage. High GFAT1 expression was identified as an independent prognostic factor which predicted poor overall survival (OS) and recurrence-free survival (RFS) in HCC patients. Incorporation of GFAT1 expression could improve the prognostic accuracy of traditional TNM stage system. Integration of GFAT1 expression with other independent prognosticators generated a predictive nomogram, which showed better prognostic efficiency for OS and RFS in HCC patients. In vitro studies also revealed that GFAT1 promoted the proliferation, cell cycle progression, migration and invasion of HCC cells. In conclusion, GFAT1 is a potential prognostic biomarker for overall survival and recurrence-free survival of HCC patients after surgery.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/enzimologia , Proliferação de Células , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Feminino , Seguimentos , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Humanos , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
10.
Sci Rep ; 6: 39044, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27996048

RESUMO

Pancreatic cancer is one of the most lethal of all types of cancer, with the 5-year survival rate ranging only at 6-7%. The aberrant glucose metabolism is one of the hallmarks of cancer cells, and as a branch of glucose metabolism, hexosamine biosynthesis pathway (HBP) has been reported to play a critical role in the insulin resistance and progression of cancer. Glutamine:fructose-6-phosphate amidotransferase (GFAT1) is the rate-limiting enzyme of the HBP; nevertheless, the prognostic value of GFAT1 in pancreatic cancer remains elusive. In this study, we found that the expression of GFAT1 was increased in pancreatic cancer samples compared to peri-tumor tissues. High expression of GFAT1 was positively associated with lymph node metastasis, pTNM stage and shorter overall survival (OS) in pancreatic cancer patients. GFAT1 was identified as an independent prognosticator for OS, and combining GFAT1 expression with pTNM stage generated a predictive nomogram, which showed better prognostic efficiency for OS in patients with pancreatic cancer. In summary, high GFAT1 expression is identified as an independent predictor of adverse clinical outcome in our small number of pancreatic cancer patients, and the practical prognostic nomogram model may help clinicians in decision making and the design of clinical studies.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/biossíntese , Proteínas de Neoplasias/biossíntese , Neoplasias Pancreáticas , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/mortalidade , Taxa de Sobrevida
11.
Oncotarget ; 7(25): 38427-39, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27509259

RESUMO

Gastric cancer remains the third leading cause of cancer-related mortality worldwide, and invasion and metastasis of gastric cancer represent the major reason for its poor prognosis. Glutamine: fructose-6-phosphate amidotransferase 1 (GFAT1) is the first and rate-limiting enzyme of hexosamine biosynthesis pathway (HBP). Nevertheless, the role of GFAT1 in gastric cancer is little investigated. In this study, we found that the expression of GFAT1 was decreased in gastric cancer. Low expression of GFAT1 was positively associated with vessel invasion, late T stage, lymph node metastasis, distant metastasis, advanced TNM stage and poor prognosis in patients with gastric cancer. Furthermore, in vitro and in vivo studies revealed that down-regulation of GFAT1 promoted epithelial-to-mesenchymal transition (EMT) and invasive activities in gastric cancer cells through inducing the expression of TGF-ß1. The GFAT1 expression also significantly correlated with EMT-related factors in gastric cancer patients. Together, these findings indicate that GFAT1 functions as a novel suppressor of EMT and tumor metastasis in gastric cancer.


Assuntos
Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/deficiência , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/patologia , Animais , Progressão da Doença , Transição Epitelial-Mesenquimal , Feminino , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/biossíntese , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/genética
12.
Cell Signal ; 28(10): 1530-6, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27443248

RESUMO

C-type lectin-like receptor 2 (CLEC-2) was originally identified as a member of non-classical C-type lectin-like receptors in platelets and immune cells. Activation of CLEC-2 is involved in thrombus formation, lymphatic/blood vessel separation, platelet-mediated tumor metastasis and immune response. Nevertheless, the regulation of CLEC-2 expression is little understood. In this study, we identified that the C terminus of Hsc70-interacting protein (CHIP) interacted with CLEC-2 by mass spectrometry analysis, and CHIP decreased the protein expression of CLEC-2 through lysine-48-linked ubiquitination and proteasomal degradation. Deleted and point mutation also revealed that CHIP controlled CLEC-2 protein expression via both tetratricopeptide repeats (TPR) domain and Ubox domain in a HSP70/90-independent manner. Moreover, reduced CHIP expression was associated with decreased CLEC-2 polyubiquitination and increased CLEC-2 protein levels in PMA-induced differentiation of THP-1 monocytes into macrophages. These results indicate that CLEC-2 is the target substrate of E3 ubiquitin ligase CHIP, and suggest that the CHIP/CLEC-2 axis may play an important role in the modulation of immune response.


Assuntos
Lectinas Tipo C/metabolismo , Glicoproteínas de Membrana/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Regulação para Baixo , Células HEK293 , Células HeLa , Humanos , Lisina/metabolismo , Ligação Proteica , Domínios Proteicos , Ubiquitina-Proteína Ligases/química , Ubiquitinação
13.
Sci Rep ; 6: 29604, 2016 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-27404891

RESUMO

Calpain-8 and calpain-9 belong to the family of calcium-dependent cysteine proteases, which are highly expressed in the stomach. However, the roles of calpain-8 and calpain-9 in gastric tumorigenesis remain little understood. Herein, we demonstrated that calpain-9 was generally decreased in gastric cancer cell lines and primary tumor tissues, while calpain-8 expression was not significantly altered. Calpain-9, but not calpain-8, induced cell cycle arrest in the G1 phase and cellular apoptosis in vitro, and it attenuated the growth of subcutaneous tumor xenografts in vivo. Low expression of calpain-9 was positively associated with male sex, late T stage, lymph node metastasis, and advanced TNM stage. Further analysis identified calpain-9 as an independent prognostic factor for poor prognosis, and combining calpain-9 with TNM stage generated a better predictive model for patient outcomes. In conclusion, calpain-9 is a tumor suppressor that can be regarded as a potential prognosis indicator for clinical outcomes in gastric cancer.


Assuntos
Calpaína/metabolismo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/metabolismo , Idoso , Animais , Apoptose , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Biochem Biophys Res Commun ; 463(4): 839-45, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26056003

RESUMO

Hepatocellular carcinoma (HCC) remains the second leading cause of cancer-related death worldwide, and elevated rates of reactive oxygen species (ROS) have long been considered as a hallmark of almost all types of cancer including HCC. Protein kinase C alpha (PKCα), a serine/threonine kinase among conventional PKC family, is recognized as a major player in signal transduction and tumor progression. Overexpression of PKCα is commonly observed in human HCC and associated with its poor prognosis. However, how PKCα is involved in hepatocellular carcinogenesis remains not fully understood. In this study, we found that among the members of conventional PKC family, PKCα, but not PKCßI or ßII, promoted ROS production in HCC cells. PKCα stimulated generation of ROS by up-regulating DUOX2 at post-transcriptional level. Depletion of DUOX2 abrogated PKCα-induced activation of AKT/MAPK pathways as well as cell proliferation, migration and invasion in HCC cells. Moreover, the expression of DUOX2 and PKCα was well positively correlated in both HCC cell lines and patient samples. Collectively, our findings demonstrate that PKCα plays a critical role in HCC development by inducing DUOX2 expression and ROS generation, and propose a strategy to target PKCα/DUOX2 as a potential adjuvant therapy for HCC treatment.


Assuntos
Carcinoma Hepatocelular/enzimologia , Neoplasias Hepáticas/enzimologia , NADPH Oxidases/metabolismo , Proteína Quinase C-alfa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sequência de Bases , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Oxidases Duais , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteína Quinase C-alfa/genética , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real
15.
Biochem Biophys Res Commun ; 463(3): 255-61, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26002467

RESUMO

Activation of quiescent hepatic stellate cells (HSCs) is the central event of liver fibrosis. The translational machinery is an optimized molecular network that affects cellular homoeostasis and diseases, whereas the role of protein translation in HSCs activation and liver fibrosis is little defined. Our previous report suggests that up-regulation of receptor for activated C-kinase 1(RACK1) in HSCs is critical for liver fibrogenesis. In this study, we found that RACK1 promoted macrophage conditioned medium (MCM)-induced assembly of eIF4F and phosphorylation of eIF4E in primary HSCs. RACK1 enhanced the translation and expression of pro-fibrogenic factors collagen 1α1, snail and cyclin E1 induced by MCM. Administration of PP242 or knock-down of eIF4E suppressed RACK1-stimulated collagen 1α1 production, proliferation and migration in primary HSCs. In addition, depletion of eIF4E attenuated thioacetamide (TAA)-induced liver fibrosis in vivo. Our data suggest that RACK1-mediated stimulation of cap-dependent translation plays crucial roles in HSCs activation and liver fibrogenesis, and targeting translation initiation could be a promising strategy for the treatment of liver fibrosis.


Assuntos
Fator de Iniciação 4F em Eucariotos/metabolismo , Células Estreladas do Fígado/patologia , Cirrose Hepática/metabolismo , Fígado/patologia , Neuropeptídeos/metabolismo , Animais , Células Cultivadas , Colágeno Tipo I/genética , Ciclina E/genética , Regulação para Baixo , Fator de Iniciação 4F em Eucariotos/genética , Células Estreladas do Fígado/metabolismo , Fígado/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/patologia , Camundongos Endogâmicos BALB C , Oligonucleotídeos Antissenso/genética , Proteínas Oncogênicas/genética , Biossíntese de Proteínas , Receptores de Quinase C Ativada , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
16.
PLoS One ; 10(3): e0121939, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25822822

RESUMO

Liver fibrosis represents the consequences of a sustained wound healing response to chronic liver injuries, and its progression toward cirrhosis is the major cause of liver-related morbidity and mortality worldwide. However, anti-fibrotic treatment remains an unconquered area for drug development. Accumulating evidence indicate that oxidative stress plays a critical role in liver fibrogenesis. In this study, we found that PQQ, a natural anti-oxidant present in a wide variety of human foods, exerted potent anti-fibrotic and ROS-scavenging activity in Balb/C mouse models of liver fibrosis. The antioxidant activity of PQQ was involved in the modulation of multiple steps during liver fibrogenesis, including chronic liver injury, hepatic inflammation, as well as activation of hepatic stellate cells and production of extracellular matrix. PQQ also suppressed the up-regulation of RACK1 in activated HSCs in vivo and in vitro. Our data suggest that PQQ suppresses oxidative stress and liver fibrogenesis in mice, and provide rationale for the clinical application of PQQ in the prevention and treatment of liver fibrosis.


Assuntos
Antioxidantes/farmacologia , Cirrose Hepática/prevenção & controle , Cofator PQQ/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/biossíntese , Modelos Animais de Doenças , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neuropeptídeos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Receptores de Quinase C Ativada , Tioacetamida/toxicidade
17.
Histopathology ; 67(5): 677-88, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25809930

RESUMO

AIMS: Ras-GTPase-activating protein SH3 domain-binding protein 1 (G3BP1) is a downstream effector of Ras signalling, and is overexpressed in several types of human malignancy. However, its role in gastric cancer remains unclear. The aim of this study was to investigate the prognostic significance of G3BP1 in gastric cancer. METHODS AND RESULTS: G3BP1 mRNA and protein levels in paired frozen tumour samples were detected by real-time polymerase chain reaction and western blotting, respectively. Paraffin-embedded tumour samples were used for immunohistochemistry. Gastric cancer cells were used to detect the tumorigenic role of G3BP1 in vitro. We found that G3BP1 protein expression was markedly increased in gastric cancer tissues as compared with corresponding non-malignant mucosa, whereas corresponding changes in mRNA levels were not observed. G3BP1 staining was positively correlated with tumour size, vascular invasion, T classification, lymph node metastasis, TNM stage, and reduced overall survival. Further analysis identified G3BP1 as an independent prognostic factor for poor prognosis, and combining G3BP1 with TNM stage generated a better predictive model for patient outcomes. G3BP1 also promoted proliferation, migration/invasion and extracellular signal-related kinase and AKT activation in gastric cancer cells. CONCLUSIONS: Our data define G3BP1 as a novel independent prognostic factor that is correlated with gastric cancer progression.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/análise , Proteínas de Transporte/biossíntese , Neoplasias Gástricas/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Idoso , Western Blotting , Proteínas de Transporte/análise , DNA Helicases , Progressão da Doença , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Proteínas de Ligação a Poli-ADP-Ribose , Prognóstico , Modelos de Riscos Proporcionais , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Análise Serial de Tecidos , Transfecção
18.
Biochem Biophys Res Commun ; 443(1): 68-73, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24269813

RESUMO

Alcoholic liver disease (ALD) is a common cause of advanced liver disease, and considered as a major risk factor of morbidity and mortality worldwide. Hepatic cholestasis is a pathophysiological feature observed in all stages of ALD. The farnesoid X receptor (FXR) is a member of the nuclear hormone receptor superfamily, and plays an essential role in the regulation of bile acid, lipid and glucose homeostasis. However, the role of FXR in the pathogenesis and progression of ALD remains largely unknown. Mice were fed Lieber-DeCarli ethanol diet or an isocaloric control diet. We used a specific agonist of FXR WAY-362450 to study the effect of pharmacological activation of FXR in alcoholic liver disease. In this study, we demonstrated that FXR activity was impaired by chronic ethanol ingestion in a murine model of ALD. Activation of FXR by specific agonist WAY-362450 protected mice from the development of ALD. We also found that WAY-362450 treatment rescued FXR activity, suppressed ethanol-induced Cyp2e1 up-regulation and attenuated oxidative stress in liver. Our results highlight a key role of FXR in the modulation of ALD development, and propose specific FXR agonists for the treatment of ALD patients.


Assuntos
Azepinas/uso terapêutico , Colestase/tratamento farmacológico , Indóis/uso terapêutico , Hepatopatias Alcoólicas/tratamento farmacológico , Fígado/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/agonistas , Animais , Colestase/patologia , Citocromo P-450 CYP2E1/metabolismo , Modelos Animais de Doenças , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/patologia , Fígado/metabolismo , Fígado/patologia , Hepatopatias Alcoólicas/patologia , Camundongos , Camundongos Knockout , Estresse Oxidativo/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/genética
19.
PLoS One ; 8(3): e60115, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555900

RESUMO

Liver fibrosis represents the consequences of a sustained wound healing response to chronic liver injury, and activation of quiescent hepatic stellate cells (HSCs) into a myofibroblast-like phenotype is considered as the central event of liver fibrosis. RACK1, the receptor for activated C-kinase 1, is a classical scaffold protein implicated in numerous signaling pathways and cellular processes; however, the role of RACK1 in liver fibrosis is little defined. Herein, we report that RACK1 is up-regulated in activated HSCs in transforming growth factor beta 1 (TGF-ß1)-dependent manner both in vitro and in vivo, and TGF-ß1 stimulates the expression of RACK1 through NF-κB signaling. Moreover, RACK1 promotes TGF-ß1 and platelet-derived growth factor (PDGF)-mediated activation of pro-fibrogenic pathways as well as the differentiation, proliferation and migration of HSCs. Depletion of RACK1 suppresses the progression of TAA-induced liver fibrosis in vivo. In addition, the expression of RACK1 in fibrogenic cells also positively correlates well with the stage of liver fibrosis in clinical cases. Our results suggest RACK1 as a downstream target gene of TGF-ß1 involved in the modulation of liver fibrosis progression in vitro and in vivo, and propose a strategy to target RACK1 for liver fibrosis treatment.


Assuntos
Cirrose Hepática/metabolismo , Neuropeptídeos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Animais , Western Blotting , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Imunoprecipitação da Cromatina , Imunofluorescência , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Neuropeptídeos/genética , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Quinase C Ativada , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/genética
20.
World J Gastroenterol ; 18(25): 3235-49, 2012 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-22783047

RESUMO

AIM: To investigate the cellular mechanisms of action of Yiguanjian (YGJ) decoction in treatment of chronic hepatic injury. METHODS: One group of mice was irradiated, and received enhanced green fluorescent protein (EGFP)-positive bone marrow transplants followed by 13 wk of CCl4 injection and 6 wk of oral YGJ administration. A second group of Institute for Cancer Research mice was treated with 13 wk of CCl4 injection and 6 wk of oral YGJ administration. Liver function, histological changes in the liver, and Hyp content were analyzed. The expression of α-smooth muscle actin (α-SMA), F4/80, albumin (Alb), EGFP, mitogen-activated protein kinase-2 (PKM2), Ki-67, α fetoprotein (AFP), monocyte chemotaxis protein-1 and CC chemokine receptor 2 were assayed. RESULTS: As hepatic damage progressed, EGFP-positive marrow cells migrated into the liver and were mainly distributed along the fibrous septa. They showed a conspicuous coexpression of EGFP with α-SMA and F4/80 but no coexpression with Alb. Moreover, the expression of PKM2, AFP and Ki-67 was enhanced dynamically and steadily over the course of liver injury. YGJ abrogated the increases in the number of bone marrow-derived fibrogenic cells in the liver, inhibited expression of both progenitor and mature hepatocyte markers, and reduced fibrogenesis. CONCLUSION: YGJ decoction improves liver fibrosis by inhibiting the migration of bone marrow cells into the liver as well as inhibiting their differentiation and suppressing the proliferation of both progenitors and hepatocytes in the injured liver.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Tetracloreto de Carbono , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/tratamento farmacológico , Regeneração Hepática/efeitos dos fármacos , Fígado/efeitos dos fármacos , Actinas/metabolismo , Administração Oral , Albuminas/metabolismo , Animais , Antígenos de Diferenciação/metabolismo , Biomarcadores/metabolismo , Células da Medula Óssea/metabolismo , Transplante de Medula Óssea , Movimento Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Quimiocina CCL2/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Antígeno Ki-67/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Receptores CCR2/metabolismo , Fatores de Tempo , alfa-Fetoproteínas/metabolismo
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