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1.
Phytomedicine ; 129: 155627, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38696924

ABSTRACT

BACKGROUND: Sepsis is a life-threatening organ dysfunction caused by an exaggerated response to infection. In the lungs, one of the most susceptible organs, this can manifest as acute respiratory distress syndrome (ARDS). Shenfu (SF) injection is a prominent traditional Chinese medicine used to treat sepsis. However, the exact mechanism of its action has rarely been reported in the literature. PURPOSE: In the present study, we detected the protective effect of SF injection on sepsis-induced ARDS and explored its underlying mechanism. METHODS: We investigated the potential targets and regulatory mechanisms of SF injections using a combination of network pharmacology and RNA sequencing. This study was conducted both in vivo and in vitro using a mouse model of ARDS and lipopolysaccharide (LPS)-stimulated MLE-12 cells, respectively. RESULTS: The results showed that SF injection could effectively inhibit inflammation, oxidative stress, and apoptosis to alleviate LPS-induced ARDS. SF inhibited the PI3K-AKT pathway, which controls autophagy and apoptosis. Subsequently, MLE-12 cells were treated with 3-methyladenine to assess its effects on autophagy and apoptosis. Additional experiments were conducted by adding rapamycin, an mTOR antagonist, or SC79, an AKT agonist, to investigate the effects of SF injection on autophagy, apoptosis, and the PI3K-AKT pathway. CONCLUSION: Overall, we found that SF administration could enhance autophagic activity, reduce apoptosis, suppress inflammatory responses and oxidative stress, and inhibit the PI3K-AKT pathway, thus ameliorating sepsis-induced ARDS.


Subject(s)
Apoptosis , Autophagy , Drugs, Chinese Herbal , Lipopolysaccharides , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Respiratory Distress Syndrome , Sepsis , Signal Transduction , Animals , Drugs, Chinese Herbal/pharmacology , Autophagy/drug effects , Sepsis/complications , Sepsis/drug therapy , Proto-Oncogene Proteins c-akt/metabolism , Apoptosis/drug effects , Respiratory Distress Syndrome/drug therapy , Phosphatidylinositol 3-Kinases/metabolism , Mice , Male , Signal Transduction/drug effects , Disease Models, Animal , Oxidative Stress/drug effects , Cell Line , Mice, Inbred C57BL , TOR Serine-Threonine Kinases/metabolism , Network Pharmacology
2.
World J Emerg Med ; 15(2): 111-120, 2024.
Article in English | MEDLINE | ID: mdl-38476533

ABSTRACT

BACKGROUND: Sepsis-related acute respiratory distress syndrome (ARDS) has a high mortality rate, and no effective treatment is available currently. Quercetin is a natural plant product with many pharmacological activities, such as antioxidative, anti-apoptotic, and anti-inflammatory effects. This study aimed to elucidate the protective mechanism of quercetin against sepsis-related ARDS. METHODS: In this study, network pharmacology and in vitro experiments were used to investigate the underlying mechanisms of quercetin against sepsis-related ARDS. Core targets and signaling pathways of quercetin against sepsis-related ARDS were screened and were verified by in vitro experiments. RESULTS: A total of 4,230 targets of quercetin, 360 disease targets of sepsis-related ARDS, and 211 intersection targets were obtained via database screening. Among the 211 intersection targets, interleukin-6 (IL-6), tumor necrosis factor (TNF), albumin (ALB), AKT serine/threonine kinase 1 (AKT1), and interleukin-1ß (IL-1ß) were identified as the core targets. A Gene Ontology (GO) enrichment analysis revealed 894 genes involved in the inflammatory response, apoptosis regulation, and response to hypoxia. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis identified 106 pathways. After eliminating and generalizing, the hypoxia-inducible factor-1 (HIF-1), TNF, nuclear factor-κB (NF-κB), and nucleotide-binding and oligomerization domain (NOD)-like receptor signaling pathways were identified. Molecular docking revealed that quercetin had good binding activity with the core targets. Moreover, quercetin blocked the HIF-1, TNF, NF-κB, and NOD-like receptor signaling pathways in lipopolysaccharide (LPS)-induced murine alveolar macrophage (MH-S) cells. It also suppressed the inflammatory response, oxidative reactions, and cell apoptosis. CONCLUSION: Quercetin ameliorates sepsis-related ARDS by binding to its core targets and blocking the HIF-1, TNF, NF-κB, and NOD-like receptor signaling pathways to reduce inflammation, cell apoptosis, and oxidative stress.

3.
Article in English | MEDLINE | ID: mdl-38321908

ABSTRACT

BACKGROUND: Sepsis-related acute respiratory distress syndrome (ARDS) is a fatal disease without effective therapy. Kaempferol is a flavonoid compound extracted from natural plant products; it exerts numerous pharmacological effects. Kaempferol attenuates sepsis-related ARDS; however, the underlying protective mechanism has not been elucidated completely. OBJECTIVE: This study aimed to use network pharmacology and experimental verification to investigate the mechanisms by which kaempferol attenuates sepsis-related ARDS. METHODS: We screened the targets of kaempferol by PharMapper, Swiss Target Prediction, and CTD database. We identified the targets of sepsis-related ARDS by GeneCards, DisGeNet, OMIM, and TTD. The Weishengxin platform was used to map the targets of both kaempferol and sepsis-related ARDS. We created a Venn diagram to identify the intersection targets. We constructed the "component-intersection targets-disease" network diagram using Cytoscape 3.9.1 software. The intersection targets were imported into the STRING database for developing the protein-protein interaction network. Metascape was used for the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. We selected the leading 20 KEGG pathways to establish the KEGG relationship network. Finally, we performed experimental verification to confirm our prediction results. RESULTS: Through database screening, we obtained 502, 360, and 78 kaempferol targets, disease targets of sepsis-related ARDS, and intersection targets, respectively. The core targets consisted of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, albumin (ALB), IL-1ß, and AKT serine/ threonine kinase (AKT)1. GO enrichment analysis identified 426 items, which were principally involved in response to lipopolysaccharide, regulation of inflammatory response, inflammatory response, positive regulation of cell migration, positive regulation of cell adhesion, positive regulation of protein phosphorylation, response to hormone, regulation of reactive oxygen species (ROS) metabolic process, negative regulation of apoptotic signaling pathway, and response to decreased oxygen levels. KEGG enrichment analysis identified 151 pathways. After eliminating the disease and generalized pathways, we obtained the hypoxia-inducible factor 1 (HIF-1), nuclear factor κB (NF-κB), and phosphoinositide 3-kinase (PI3K)-Akt signaling pathways. Our experimental verification confirmed that kaempferol blocked the HIF-1, NF-κB, and PI3K-Akt signaling pathways, diminished TNF-α, IL-1ß, and IL-6 expressions, suppressed ROS production, and inhibited apoptosis in lipopolysaccharide (LPS)-induced murine alveolar macrophage (MH-S) cells. CONCLUSION: Kaempferol can reduce inflammatory response, ROS production, and cell apoptosis by acting on the HIF-1, NF-κB, and PI3K-Akt signaling pathways, thereby alleviating sepsis- related ARDS.

4.
Cell Genom ; 3(11): 100364, 2023 Nov 08.
Article in English | MEDLINE | ID: mdl-38020968

ABSTRACT

Aneuploidy compromises genomic stability, often leading to embryo inviability, and is frequently associated with tumorigenesis and aging. Different aneuploid chromosome stoichiometries lead to distinct transcriptomic and phenotypic changes, making it helpful to study aneuploidy in tightly controlled genetic backgrounds. By deploying the engineered SCRaMbLE (synthetic chromosome rearrangement and modification by loxP-mediated evolution) system to the newly synthesized megabase Sc2.0 chromosome VII (synVII), we constructed a synthetic disomic yeast and screened hundreds of SCRaMbLEd derivatives with diverse chromosomal rearrangements. Phenotypic characterization and multi-omics analysis revealed that fitness defects associated with aneuploidy could be restored by (1) removing most of the chromosome content or (2) modifying specific regions in the duplicated chromosome. These findings indicate that both chromosome copy number and specific chromosomal regions contribute to the aneuploidy-related phenotypes, and the synthetic chromosome resource opens new paradigms in studying aneuploidy.

5.
Nat Commun ; 14(1): 6487, 2023 10 14.
Article in English | MEDLINE | ID: mdl-37838746

ABSTRACT

Synthetic auxotrophy in which cell viability depends on the presence of an unnatural amino acid (unAA) provides a powerful strategy to restrict unwanted propagation of genetically modified organisms (GMOs) in open environments and potentially prevent industrial espionage. Here, we describe a generic approach for robust biocontainment of budding yeast dependent on unAA. By understanding escape mechanisms, we specifically optimize our strategies by introducing designed "immunity" to the generation of amber-suppressor tRNAs and developing the transcriptional- and translational-based biocontainment switch. We further develop a fitness-oriented screening method to easily obtain multiplex safeguard strains that exhibit robust growth and undetectable escape frequency (<~10-9) on solid media for 14 days. Finally, we show that employing our multiplex safeguard system could restrict the proliferation of strains of interest in a real fermentation scenario, highlighting the great potential of our yeast biocontainment strategy to protect the industrial proprietary strains.


Subject(s)
Amino Acids , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Amino Acids/metabolism , Organisms, Genetically Modified , RNA, Transfer/metabolism
6.
Cell Rep ; 42(7): 112802, 2023 07 25.
Article in English | MEDLINE | ID: mdl-37453065

ABSTRACT

Schwann cells play critical roles in peripheral neuropathies; however, the regulatory mechanisms of their homeostasis remain largely unknown. Here, we show that nucleoporin Seh1, a component of nuclear pore complex, is important for Schwann cell homeostasis. Expression of Seh1 decreases as mice age. Loss of Seh1 leads to activated immune responses and cell necroptosis. Mice with depletion of Seh1 in Schwann cell lineage develop progressive reduction of Schwann cells in sciatic nerves, predominantly non-myelinating Schwann cells, followed by neural fiber degeneration and malfunction of the sensory and motor system. Mechanistically, Seh1 safeguards genome stability by mediating the interaction between SETDB1 and KAP1. The disrupted interaction after ablation of Seh1 derepresses endogenous retroviruses, which triggers ZBP1-dependent necroptosis in Schwann cells. Collectively, our results demonstrate that Seh1 is required for Schwann cell homeostasis by maintaining genome integrity and suggest that decrease of nucleoporins may participate in the pathogenesis of periphery neuropathies.


Subject(s)
Nuclear Pore Complex Proteins , Peripheral Nervous System Diseases , Animals , Mice , Genomic Instability , Myelin Sheath/metabolism , Necroptosis , Nuclear Pore Complex Proteins/genetics , Nuclear Pore Complex Proteins/metabolism , Peripheral Nervous System Diseases/metabolism , Schwann Cells/metabolism , Sciatic Nerve/metabolism
7.
Zhongguo Zhong Yao Za Zhi ; 48(12): 3345-3359, 2023 Jun.
Article in Chinese | MEDLINE | ID: mdl-37382018

ABSTRACT

The aim of this study was to investigate the effect and molecular mechanism of Xuebijing Injection in the treatment of sepsis-associated acute respiratory distress syndrome(ARDS) based on network pharmacology and in vitro experiment. The active components of Xuebijing Injection were screened and the targets were predicted by the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP). The targets of sepsis-associated ARDS were searched against GeneCards, DisGeNet, OMIM, and TTD. Weishengxin platform was used to map the targets of the main active components in Xuebijing Injection and the targets of sepsis-associated ARDS, and Venn diagram was established to identify the common targets. Cytoscape 3.9.1 was used to build the "drug-active components-common targets-disease" network. The common targets were imported into STRING for the building of the protein-protein interaction(PPI) network, which was then imported into Cytoscape 3.9.1 for visualization. DAVID 6.8 was used for Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment of the common targets, and then Weishe-ngxin platform was used for visualization of the enrichment results. The top 20 KEGG signaling pathways were selected and imported into Cytoscape 3.9.1 to establish the KEGG network. Finally, molecular docking and in vitro cell experiment were performed to verify the prediction results. A total of 115 active components and 217 targets of Xuebijing Injection and 360 targets of sepsis-associated ARDS were obtained, among which 63 common targets were shared by Xuebijing Injection and the disease. The core targets included interleukin-1 beta(IL-1ß), IL-6, albumin(ALB), serine/threonine-protein kinase(AKT1), and vascular endothelial growth factor A(VEGFA). A total of 453 GO terms were annotated, including 361 terms of biological processes(BP), 33 terms of cellular components(CC), and 59 terms of molecular functions(MF). The terms mainly involved cellular response to lipopolysaccharide, negative regulation of apoptotic process, lipopolysaccharide-mediated signaling pathway, positive regulation of transcription from RNA polyme-rase Ⅱ promoter, response to hypoxia, and inflammatory response. The KEGG enrichment revealed 85 pathways. After diseases and generalized pathways were eliminated, hypoxia-inducible factor-1(HIF-1), tumor necrosis factor(TNF), nuclear factor-kappa B(NF-κB), Toll-like receptor, and NOD-like receptor signaling pathways were screened out. Molecular docking showed that the main active components of Xuebijing Injection had good binding activity with the core targets. The in vitro experiment confirmed that Xuebijing Injection suppressed the HIF-1, TNF, NF-κB, Toll-like receptor, and NOD-like receptor signaling pathways, inhibited cell apoptosis and reactive oxygen species generation, and down-regulated the expression of TNF-α, IL-1ß, and IL-6 in cells. In conclusion, Xuebijing Injection can regulate apoptosis and response to inflammation and oxidative stress by acting on HIF-1, TNF, NF-κB, Toll-like receptor, and NOD-like receptor signaling pathways to treat sepsis-associated ARDS.


Subject(s)
Respiratory Distress Syndrome , Sepsis , Humans , Network Pharmacology , Vascular Endothelial Growth Factor A , NF-kappa B , Interleukin-6 , Lipopolysaccharides , Molecular Docking Simulation , Tumor Necrosis Factor-alpha , Sepsis/complications , Sepsis/drug therapy , Sepsis/genetics , NLR Proteins
8.
Front Cell Infect Microbiol ; 12: 929856, 2022.
Article in English | MEDLINE | ID: mdl-36046746

ABSTRACT

Objective: To evaluate the diagnostic performance of metagenomic next-generation sequencing (mNGS) and culture in pathogen detection among intensive care unit (ICU) and non-ICU patients with suspected pulmonary infection. Methods: In this prospective study, sputum samples were collected from patients with suspected pulmonary infection for 2 consecutive days and then subjected to DNA or RNA sequencing by mNGS or culture; 62 ICU patients and 60 non-ICU patients were admitted. In the end, comparisons were made on the pathogen species identified by mNGS and culture, the overall performance of these two methods in pathogen detection, and the most common pathogens detected by mNGS between the ICU and non-ICU groups. Results: In DNA and RNA sequencing, the positive rate of pathogen detection reached 96.69% (117/121) and 96.43% (108/112), respectively. In culture tests, the positive rate of the pathogen was 39.34% (48/122), much lower than that of DNA and RNA sequencing. In general, the positive rate of pathogen detection by sputum mNGS was significantly higher than that of sputum culture in the total and non-ICU groups (p < 0.001) but did not show a significant difference when compared to the result of sputum culture in the ICU group (p = 0.08). Haemophilus spp., Candida albicans, Enterococcus spp., and viruses from the mNGS results were excluded before comparing the overall performance of these two methods in pathogen detection. Specifically, among the 10 most common bacteria implied from the mNGS results, significant differences were observed in the number of cases of Haemophilus parainfluenzae, Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Staphylococcus aureus, and Enterococcus faecalis between the ICU and non-ICU groups (p < 0.05). Conclusions: This study demonstrated the superiority of mNGS over culture in detecting all kinds of pathogen species in sputum samples. These results indicate that mNGS may serve as a valuable tool to identify pathogens, especially for ICU patients who are more susceptible to mixed infections.


Subject(s)
Metagenomics , Pneumonia , High-Throughput Nucleotide Sequencing/methods , Humans , Metagenome , Metagenomics/methods , Pneumonia/microbiology , Prospective Studies , Sensitivity and Specificity
9.
Entropy (Basel) ; 24(5)2022 May 03.
Article in English | MEDLINE | ID: mdl-35626526

ABSTRACT

As a non-deterministic polynomial hard (NP-hard) problem, the shortest common supersequence (SCS) problem is normally solved by heuristic or metaheuristic algorithms. One type of metaheuristic algorithms that has relatively good performance for solving SCS problems is the chemical reaction optimization (CRO) algorithm. Several CRO-based proposals exist; however, they face such problems as unstable molecular population quality, uneven distribution, and local optimum (premature) solutions. To overcome these problems, we propose a new approach for the search mechanism of CRO-based algorithms. It combines the opposition-based learning (OBL) mechanism with the previously studied improved chemical reaction optimization (IMCRO) algorithm. This upgraded version is dubbed OBLIMCRO. In its initialization phase, the opposite population is constructed from a random population based on OBL; then, the initial population is generated by selecting molecules with the lowest potential energy from the random and opposite populations. In the iterative phase, reaction operators create new molecules, where the final population update is performed. Experiments show that the average running time of OBLIMCRO is more than 50% less than the average running time of CRO_SCS and its baseline algorithm, IMCRO, for the desoxyribonucleic acid (DNA) and protein datasets.

10.
Entropy (Basel) ; 24(3)2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35327828

ABSTRACT

In mobile edge computing systems, the edge server placement problem is mainly tackled as a multi-objective optimization problem and solved with mixed integer programming, heuristic or meta-heuristic algorithms, etc. These methods, however, have profound defect implications such as poor scalability, local optimal solutions, and parameter tuning difficulties. To overcome these defects, we propose a novel edge server placement algorithm based on deep q-network and reinforcement learning, dubbed DQN-ESPA, which can achieve optimal placements without relying on previous placement experience. In DQN-ESPA, the edge server placement problem is modeled as a Markov decision process, which is formalized with the state space, action space and reward function, and it is subsequently solved using a reinforcement learning algorithm. Experimental results using real datasets from Shanghai Telecom show that DQN-ESPA outperforms state-of-the-art algorithms such as simulated annealing placement algorithm (SAPA), Top-K placement algorithm (TKPA), K-Means placement algorithm (KMPA), and random placement algorithm (RPA). In particular, with a comprehensive consideration of access delay and workload balance, DQN-ESPA achieves up to 13.40% and 15.54% better placement performance for 100 and 300 edge servers respectively.

11.
Entropy (Basel) ; 24(3)2022 Mar 19.
Article in English | MEDLINE | ID: mdl-35327936

ABSTRACT

Space exploration is a hot topic in the application field of mobile robots. Proposed solutions have included the frontier exploration algorithm, heuristic algorithms, and deep reinforcement learning. However, these methods cannot solve space exploration in time in a dynamic environment. This paper models the space exploration problem of mobile robots based on the decision-making process of the cognitive architecture of Soar, and three space exploration heuristic algorithms (HAs) are further proposed based on the model to improve the exploration speed of the robot. Experiments are carried out based on the Easter environment, and the results show that HAs have improved the exploration speed of the Easter robot at least 2.04 times of the original algorithm in Easter, verifying the effectiveness of the proposed robot space exploration strategy and the corresponding HAs.

12.
Oncol Rep ; 38(6): 3531-3537, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29130109

ABSTRACT

Ubiquitin specific peptidase 9, X-linked (USP9X), a significant regulatory protease in protein ubiquitination, has been proven to act as a proto-oncogene in several types of cancers, such as cervix, colon, breast, brain and lung cancers. The prognosis of patients with pancreatic ductal adenocarcinoma (PDAC) is extremely poor due to its high invasive and metastatic abilities. Nevertheless, whether USP9X acts as a proto-oncogene or a tumor-suppressor gene in PDAC is controversial and the mechanism of metastasis remains unknown. The present study focused on the effect of USP9X on the migration, invasion and apoptosis of PADC cells. We analyzed the expression of USP9X in pancreatic cancer tissues of different pathologic grades by immunohistochemical analysis. USP9X expression in the pancreatic cancer tissues was markedly increased in contrast to that noted in the adjacent non-tumor tissues. USP9X expression in PANC-1 cells was downregulated after transfection of shRNA-USP9X. Knockdown of endogenous USP9X expression evidently inhibited the migration and invasion of PANC-1 cells, and promoted cell apoptosis. Meanwhile, expression levels of Snail, Twist, N-cadherin and vimentin were downregulated. E-cadherin expression was negatively correlated with USP9X expression and the expression of survivin was also downregulated in the PANC-1 cells. In brief, USP9X promoted the migration and invasion of PANC-1 cells probably by provoking epithelial-mesenchymal transition, and also inhibited apoptosis. We believe that USP9X is a major oncogene that may play a significant role in the treatment and prognosis of PDAC.


Subject(s)
Carcinoma, Pancreatic Ductal/metabolism , Pancreatic Neoplasms/metabolism , Ubiquitin Thiolesterase/metabolism , Up-Regulation , Antigens, CD/metabolism , Apoptosis , Cadherins/metabolism , Cell Line, Tumor , Cell Movement , Epithelial-Mesenchymal Transition , Female , Gene Expression Regulation, Neoplastic , Humans , Male , Neoplasm Grading , Neoplasm Invasiveness , Proto-Oncogene Mas , Snail Family Transcription Factors/metabolism , Twist Transcription Factors/metabolism
13.
Nutrition ; 31(5): 733-9, 2015 May.
Article in English | MEDLINE | ID: mdl-25837221

ABSTRACT

OBJECTIVES: Previous studies have shown duodenal-jejunal exclusion (DJE) results in the rapid resolution of type 2 diabetes; however, the underlying mechanism is unknown. This study aimed to measure the hepatic expression of insulin receptor substrate-2 (IRS-2) and glucose transporter-2 (GLUT-2) in type 2 diabetic rats post-DJE, and to investigate their roles in improved hepatic insulin resistance and glucose intolerance. METHODS: Type 2 diabetic Sprague-Dawley (SD) rats were randomly divided into DJE operation (DO) and control (DC) groups. Normal SD rats were also divided into DJE operation and control groups. Fasting plasma glucose and insulin concentrations were measured, and the quantitative insulin sensitivity check index (QUICKI) and Homeostasis Model Assessment Insulin Resistance (HOMA-IR) were calculated. Eight weeks postoperation, the hepatic IRS-2 and GLUT-2 protein and mRNA levels were measured using western blotting and reverse transcription polymerase chain reaction, respectively. RESULTS: The fasting blood glucose in the DO group decreased from a preoperative level of 20.21 ± 2.14 mmol/L to 8.50 ± 2.19 mmol/L (P < 0.05) 8 wk post-DJE. A change in the QUICKI revealed a dramatic increase, and HOMA-IR showed a significant decrease in the DO group (P < 0.05). Additionally, the IRS-2 and GLUT-2 protein and mRNA levels at 8 wk postoperation were significantly increased in the DO group compared with the DC group. CONCLUSIONS: DJE led to upregulated hepatic IRS-2 and GLUT-2 expression in the hepatic insulin signaling pathway and improved insulin sensitivity in type 2 diabetic rats.


Subject(s)
Diabetes Mellitus, Experimental/surgery , Duodenum/surgery , Gastric Bypass/methods , Insulin Resistance , Jejunum/surgery , Liver/metabolism , Signal Transduction , Animals , Blood Glucose/analysis , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/metabolism , Disease Models, Animal , Glucose Transporter Type 2/metabolism , Insulin/blood , Insulin Receptor Substrate Proteins/metabolism , Male , Rats , Rats, Sprague-Dawley , Treatment Outcome , Up-Regulation
14.
Cell Rep ; 7(3): 871-82, 2014 May 08.
Article in English | MEDLINE | ID: mdl-24746824

ABSTRACT

RAS genes are among the most frequently mutated proto-oncogenes in cancer. However, how Ras stability is regulated remains largely unknown. Here, we report a regulatory loop involving the E3 ligase Nedd4-1, Ras, and PTEN. We found that Ras signaling stimulates the expression of Nedd4-1, which in turn acts as an E3 ubiquitin ligase that regulates Ras levels. Importantly, Ras activation, either by oncogenic mutations or by epidermal growth factor (EGF) signaling, prevents Nedd4-1-mediated Ras ubiquitination. This leads to Ras-induced Nedd4-1 overexpression, and subsequent degradation of the tumor suppressor PTEN in both human cancer samples and cancer cells. Our study thus unravels the molecular mechanisms underlying the interplay of Ras, Nedd4-1, and PTEN and suggests a basis for the high prevalence of Ras-activating mutations and EGF hypersignaling in cancer.


Subject(s)
Endosomal Sorting Complexes Required for Transport/metabolism , Ubiquitin-Protein Ligases/metabolism , ras Proteins/metabolism , Animals , Carcinogenesis , Cell Line, Tumor , Endosomal Sorting Complexes Required for Transport/antagonists & inhibitors , Endosomal Sorting Complexes Required for Transport/genetics , Epidermal Growth Factor/metabolism , HEK293 Cells , HeLa Cells , Hep G2 Cells , Humans , Mice , Mice, Nude , NIH 3T3 Cells , Nedd4 Ubiquitin Protein Ligases , Neoplasms/metabolism , Neoplasms/pathology , PTEN Phosphohydrolase/metabolism , Protein Binding , Signal Transduction , Transplantation, Heterologous , Ubiquitin-Protein Ligases/antagonists & inhibitors , Ubiquitin-Protein Ligases/genetics , Ubiquitination , Up-Regulation
15.
Biochem Biophys Res Commun ; 446(1): 160-6, 2014 Mar 28.
Article in English | MEDLINE | ID: mdl-24582562

ABSTRACT

Heat shock protein 90 (Hsp90) has been predicted to be involved in hepatocellular carcinoma (HCC) therapy; however, the mechanisms of action remain elusive. SNX-2112 is an Hsp90 inhibitor showing broad antitumor activity. Here we aim to determine the role of the endoplasmic reticulum (ER) stress in SNX-2112-induced apoptosis in HCC cells. In general, three HCC cells (i.e., HepG2, Huh7, and SK-Hep1) were used in our experiments. The cell viability was determined by the CCK-8 assay. The apoptosis was analyzed using flow cytometry, laser scanning confocal microscopy (LSM) and Western blotting. The efficacy and mechanisms of action of SNX-2112 were also evaluated in a mouse xenograft model. We found that SNX-2112 showed stronger inhibition on cell growth than 17-AAG, a classical Hsp90 inhibitor. SNX-2112 treatment led to the caspase-dependent apoptosis. Interestingly, SNX-2112 decreased the expression levels of the ER chaperone proteins calnexin and immunoglobulin binding protein (BiP). It also inhibited all three ER stress sensors, namely, inositol-requiring gene 1 (IRE1), PKR-like ER kinase (PERK), and activating transcription factor 6 (ATF-6) in vitro and/or in vivo. However, the ER stress inducer tunicamycin strongly enhanced SNX-2112-induced apoptosis, whereas the IRE1 knockdown did not. Taken together, we for the first time indicated the possible apoptotic pathways of SNX-2112 in HCC cells, raising the possibility that the induction of ER stress might be favorable for SNX-2112-induced apoptosis.


Subject(s)
Apoptosis/drug effects , Carcinoma, Hepatocellular/drug therapy , Endoplasmic Reticulum Stress/drug effects , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Heterocyclic Compounds, 4 or More Rings/pharmacology , Liver Neoplasms/drug therapy , Animals , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Caspases/metabolism , Cell Line, Tumor , Hep G2 Cells , Heterografts , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Tunicamycin/pharmacology , Unfolded Protein Response/drug effects
16.
Int J Oncol ; 41(6): 2276-84, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23076967

ABSTRACT

BJ-B11 is a selective heat shock protein 90 (Hsp90) inhibitor that has been reported to possess significant antitumor activity in multiple types of cancer cells; however, the mechanism of action needs to be further clarified. We investigated, for the first time, the antitumor activity and the molecular mechanism underlying growth inhibition in Eca-109 cells. The results revealed that BJ-B11 inhibited the proliferation of Eca-109 cells in a time- and concentration-dependent manner, with 50% inhibitory concentration (IC(50)) values of 0.31±0.01 µM after 48-h incubation. BJ-B11 induced concentration-dependent G2/M cell cycle arrest and apoptosis. The cleavage of caspase 3 and PARP signals detected might originate from mitochondrial dysfunction, which was supported by the results of reactive oxygen species (ROS) production, cytochrome c release and the mitochondrial membrane potential (MMP) reduction. The general caspase inhibitor Z-VAD-fmk did not completely abolish BJ-B11-induced cell death. Furthermore, inhibition of the Akt/mTOR/p70S6K signaling pathway might be involved in the process of BJ-B11-induced autophagy, which was characterized by the production of autophagic vacuoles and upregulation of LC3-II protein in a time- and concentration-dependent manner. Meanwhile, the general autophagy inhibitor 3-MA decreased the apoptotic ratio. Furthermore, BJ-B11 induced the polymerization of cytoskeleton ß-tubulin and F-actin. Taken together, our results suggest that the growth inhibition of Eca-109 cells induced by BJ-B11 may result from the induction of G2/M cell cycle arrest, apoptosis and autophagy.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Autophagy/drug effects , Benzamides/pharmacology , Cell Cycle Checkpoints/drug effects , Indazoles/pharmacology , Actins/metabolism , Carcinoma, Squamous Cell/metabolism , Caspases/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Esophageal Neoplasms/metabolism , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Humans , Mitochondria/drug effects , Mitochondria/metabolism , Protein Multimerization/drug effects , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Ribosomal Protein S6 Kinases, 70-kDa/antagonists & inhibitors , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/antagonists & inhibitors , Tubulin/metabolism
17.
J Virol ; 86(16): 8440-51, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22623803

ABSTRACT

Herpes simplex virus 1 (HSV-1) invades the nervous system and causes pathological changes. In this study, we defined the remodeling of F-actin and its possible mechanisms during HSV-1 infection of neuronal cells. HSV-1 infection enhanced the formation of F-actin-based structures in the early stage of infection, which was followed by a continuous decrease in F-actin during the later stages of infection. The disruption of F-actin dynamics by chemical inhibitors significantly reduced the efficiency of viral infection and intracellular HSV-1 replication. The active form of the actin-depolymerizing factor cofilin 1 was found to increase at an early stage of infection and then to continuously decrease in a manner that corresponded to the remodeling pattern of F-actin, suggesting that cofilin 1 may be involved in the biphasic F-actin dynamics induced by HSV-1 infection. Knockdown of cofilin 1 impaired HSV-1-induced F-actin assembly during early infection and inhibited viral entry; however, overexpression of cofilin 1 did not affect F-actin assembly or viral entry during early infection but decreased intracellular viral reproduction efficiently. Our results, for the first time, demonstrated the biphasic F-actin dynamics in HSV-1 neuronal infection and confirmed the association of F-actin with the changes in the expression and activity of cofilin 1. These results may provide insight into the mechanism by which HSV-1 productively infects neuronal cells and causes pathogenesis.


Subject(s)
Actins/metabolism , Cofilin 1/metabolism , Herpesvirus 1, Human/physiology , Neurons/metabolism , Neurons/virology , Virus Internalization , Virus Replication , Cell Line , Humans
18.
Oncol Rep ; 27(6): 1904-10, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22447251

ABSTRACT

SNX-2112 is a selective heat shock protein 90 (Hsp90) inhibitor which can exert a potent anticancer activity. In this study, we investigated the effects of SNX-2112 on B16 melanoma cells in vitro and in vivo. The 3-(4,5-dimetrylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis demonstrated that SNX-2112 dose-dependently inhibited the growth of B16 cells, and induced G0/G1 cell cycle arrest and apoptosis. Western blotting revealed that SNX-2112 lead to the degradation of Hsp90 client proteins including Akt, IKKα, NF-κB, B-Raf and GSK3ß. Furthermore, we assessed the antitumor effect of SNX-2112 in vivo, using a xenograft model in C57BL/6 mice. Oral administration of SNX-2112 significantly inhibited the growth of B16 tumors in mice, with a 47% inhibition observed at dose of 80 mg/kg/day for 15 days, compared to control tumors. Hematoxylin-eosin (H&E) staining of xenograft tissues showed that SNX-2112 also inhibited angiogenesis and lead to a lower blood vessel density in the tumors, compared to the control group. These findings demonstrate that SNX-2112 can exhibit a potent anticancer activity against B16 melanoma cells both in vitro and in vivo, by inhibiting cell proliferation and inducing cell cycle arrest and apoptosis in a mechanism dependent on the degradation of Hsp90 client proteins.


Subject(s)
Antineoplastic Agents/pharmacology , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Heterocyclic Compounds, 4 or More Rings/pharmacology , Melanoma, Experimental/drug therapy , Animals , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , G1 Phase Cell Cycle Checkpoints/drug effects , Glycogen Synthase Kinase 3/antagonists & inhibitors , Glycogen Synthase Kinase 3 beta , HSP90 Heat-Shock Proteins/metabolism , I-kappa B Kinase/antagonists & inhibitors , Melanoma, Experimental/pathology , Mice , Mice, Inbred C57BL , Mitogen-Activated Protein Kinases/antagonists & inhibitors , NF-kappa B/drug effects , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Xenograft Model Antitumor Assays
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