ABSTRACT
With the inappropriate use of antibiotics, antibiotic resistance has emerged as a major dilemma for patients infected with Pseudomonas aeruginosa. Elastase B (LasB), a crucial extracellular virulence factor secreted by P. aeruginosa, has been identified as a key target for antivirulence therapy. Quercetin, a natural flavonoid, exhibits promising potential as an antivirulence agent. We aim to evaluate the impact of quercetin on P. aeruginosa LasB and elucidate the underlying mechanism. Molecular docking and molecular dynamics simulation revealed a rather favorable intermolecular interaction between quercetin and LasB. At the sub-MICs of ≤256 µg/ml, quercetin was found to effectively inhibit the production and activity of LasB elastase, as well as downregulate the transcription level of the lasB gene in both PAO1 and clinical strains of P. aeruginosa. Through correlation analysis, significant positive correlations were shown between the virulence gene lasB and the QS system regulatory genes lasI, lasR, rhlI, and rhlR in clinical strains of P. aeruginosa. Then, we found the lasB gene expression and LasB activity were significantly deficient in PAO1 ΔlasI and ΔlasIΔrhlI mutants. In addition, quercetin significantly downregulated the expression levels of regulated genes lasI, lasR, rhlI, rhlR, pqsA, and pqsR as well as effectively attenuated the synthesis of signaling molecules 3-oxo-C12-HSL and C4-HSL in the QS system of PAO1. Quercetin was also able to compete with the natural ligands OdDHL, BHL, and PQS for binding to the receptor proteins LasR, RhlR, and PqsR, respectively, resulting in the formation of more stabilized complexes. Taken together, quercetin exhibits enormous potential in combating LasB production and activity by disrupting the QS system of P. aeruginosa in vitro, thereby offering an alternative approach for the antivirulence therapy of P. aeruginosa infections. KEY POINTS: ⢠Quercetin diminished the content and activity of LasB elastase of P. aeruginosa. ⢠Quercetin inhibited the QS system activity of P. aeruginosa. ⢠Quercetin acted on LasB based on the QS system.
Subject(s)
Pseudomonas aeruginosa , Quercetin , Humans , Quercetin/pharmacology , Virulence , Pseudomonas aeruginosa/genetics , Molecular Docking Simulation , Pancreatic ElastaseABSTRACT
The escalating prevalence of carbapenem-resistant Pseudomonas aeruginosa (CRPA) poses a significant threat to global public health through the spread of its 'high-risk' clones. Immediate and decisive research into antimicrobial agents against CRPA is crucial for the development of effective measures and interventions. Overexpression of the MexAB-OprM efflux pump is one of the major mechanisms of CRPA. Since the active efflux of antibacterial agents plays a significant role in mediating drug resistance in CRPA, the inhibition of efflux pumps has become a promising strategy to restore antibacterial potency. Piperine (PIP) has been proven to be a promising efflux pump inhibitor in some bacteria. However, there are no studies on whether PIP can act as a potential efflux pump inhibitor in CRPA. The present study aimed to identify the antibacterial activity of PIP against CRPA and to evaluate the effect on the MexAB-OprM efflux pump. Molecular docking was used to analyze the possible interaction of PIP with the proteins of the MexAB-OprM efflux pump in CRPA. The effect of PIP on the expression of the MexAB-OprM efflux pump was investigated by real-time quantitative PCR (qPCR) and ethidium bromide accumulation efflux assay. The effect of PIP on CRPA imipenem (IPM) resistance was investigated by the checkerboard dilution method. The results demonstrated that PIP exhibited the lowest binding affinity of -9.1 kcal towards efflux pump proteins. A synergistic effect between PIP and IPM on CRPA was observed. More importantly, PIP effectively hindered the efflux of ethidium bromide and IPM by up-regulating MexR gene expression while down-regulating MexA, MexB, and OprM gene expressions. In conclusion, PIP could enhance the antibacterial activity of IPM by inhibiting the MexAB-OprM efflux pump. Our work proved that PIP had the potential to be an efflux pump inhibitor of CRPA.
Subject(s)
Imipenem , Pseudomonas aeruginosa , Imipenem/pharmacology , Bacterial Outer Membrane Proteins/genetics , Bacterial Outer Membrane Proteins/metabolism , Ethidium/pharmacology , Molecular Docking Simulation , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Microbial Sensitivity TestsABSTRACT
BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) is the most common squamous cell carcinoma. Though significant effort has been focused on molecular pathogenesis, development, and recurrence of LSCC, little is known about its relationship with the immune-related long non-coding RNA (lncRNA) pairs. METHODS: After obtaining the transcriptome profiling data sets and the corresponding clinical characteristics of LSCC patients and normal samples from The Cancer Genome Atlas (TCGA) database, a series of bioinformatic analysis was conducted to select the differently expressed immune-related lncRNAs and build a signature of immune-related lncRNA pairs. Then, the effectiveness of the signature was validated. RESULTS: A total of 111 LSCC patients and 12 normal samples' transcriptome profiling data sets were retrieved from TCGA. 301 differently expressed immune-related lncRNAs were identified and 35,225 lncRNA pairs were established. After univariate Cox analysis, LASSO regression and multivariate Cox analysis, 7 lncRNA pairs were eventually selected to construct a signature. The riskscore was computed using the following formula: Riskscore = 0.95 × (AL133330.1|AC132872.3) + (-1.23) × (LINC01094|LINC02154) + 0.65 × (LINC02575|AC122685.1) + (-1.15) × (MIR9-3HG|LINC01748) + 1.45 × (AC092687.3|SNHG12) + (-0.87) × (AC090204.1|AL158166.1) + 0.64 × (LINC01063|Z82243.1). Patients were classified into the high-risk group (> 1.366) and the low-risk group (< 1.366) according to the cutoff value (1.366), which is based on the 5-year riskscore ROC curve. The survival analysis showed that the low-risk group had a better prognosis (P < 0.001). The riskscore was better than other clinical characteristics in prognostic prediction and the area under the curves (AUCs) for the 1-, 3-, and 5-year survivals were 0.796, 0.946, and 0.895, respectively. Combining age, gender, grade, stage, and riskscore, a nomograph was developed to predict survival probability in LSCC patients. Then, the riskscore was confirmed to be related with the content of tumor-infiltration immune cells and the model could serve as a potential predictor for chemosensitivity. CONCLUSION: We successfully established a more stable signature of 7 immune-related lncRNA pairs, which has demonstrated a better prognostic ability for LSCC patients and may assist clinicians to precisely prescribe chemo drugs.
Subject(s)
Laryngeal Neoplasms , RNA, Long Noncoding , Squamous Cell Carcinoma of Head and Neck , Biomarkers, Tumor/genetics , Gene Expression Profiling , Humans , Laryngeal Neoplasms/genetics , Prognosis , RNA, Long Noncoding/genetics , Squamous Cell Carcinoma of Head and Neck/geneticsABSTRACT
Hyperlipidemia is a chronic metabolic disease caused by the abnormal metabolism of lipoproteins in the human body. Its main hazard is to accelerate systemic atherosclerosis, which causes cerebrovascular diseases such as coronary heart disease and thrombosis. At the same time, although the current hypolipidemic drugs have a certain therapeutic effect, they have side effects such as liver damage and digestive tract discomfort. Many kinds of polysaccharides from natural resources possess therapeutic effects on hyperlipidemia but still lack a comprehensive understanding. In this paper, the research progress of natural polysaccharides on reducing blood lipids in recent years is reviewed. The pharmacological mechanisms and targets of natural polysaccharides are mainly introduced. The relationship between structure and hypolipidemic activity is also discussed in detail. This review will help to understand the value of polysaccharides in lowering blood lipids and provide guidance for the development and clinical application of new hypolipidemic drugs.
Subject(s)
Hyperlipidemias , Hypolipidemic Agents , Humans , Hyperlipidemias/drug therapy , Hypolipidemic Agents/chemistry , Hypolipidemic Agents/pharmacology , Hypolipidemic Agents/therapeutic use , Natural Resources , Polysaccharides/chemistry , Polysaccharides/pharmacology , Polysaccharides/therapeutic useABSTRACT
There are 200-500 species of Potentilla(Rosaceae) worldwide, among which 90 species are widely distributed in China and have a long history of ethnic medicinal use. According to our statistics, a total of 367 compounds have been isolated and identified from plants of this genus, including terpenoids, flavonoids, phenolic acids, tannins, and phenylpropanoids. The medicinal materials made from these plants mainly have antioxidative, blood sugar-lowering, anti-inflammatory, anti-tumor, cardiovascular system-protecting, neuroprotective, and hepatoprotective activities. This study systematically reviews the research progress on chemical constituents and pharmacological activities of Potentilla plants to provide a basis for further research and clinical application.
Subject(s)
Drugs, Chinese Herbal , Potentilla , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Plant Extracts/pharmacologyABSTRACT
BACKGROUND Sudden sensorineural hearing loss (SSNHL) is currently treated with a combination of drugs, predominantly with glucocorticoids (GCs). However, the mechanisms of action of GCs in SSNHL are unknown. This study aimed to analyze the role of endoplasmic reticulum stress (ERS) in SSNHL pathogenesis and prognosis. MATERIAL AND METHODS In this study, we evaluated the expression and activation status of the protein kinase RNA-like endoplasmic reticulum kinase (PERK)-C/EBP homologous protein (CHOP) pathway in peripheral blood mononuclear cells (PBMCs) from patients with SSNHL and compared them with those in healthy controls. We also compared differences in expression of activating transcription factor 4 (ATF4) and CHOP before and after glucocorticoid treatment in patients with improved and unimproved SSNHL. RESULTS Treatment with GCs significantly improved hearing in 55% of patients with SSNHL. Levels of phosphorylated PERK (p-PERK) and phosphorylated eukaryotic initiation factor 2alpha were increased in PBMCs from patients with SSNHL compared with healthy controls. ATF4 and CHOP expression were also significantly elevated. After treatment, the amount of ATF4 and CHOP proteins in PBMCs in the patients whose SSNHL improved was significantly reduced compared with the levels measured before treatment in all patients with SSNHL. The expression of the ATF4 and CHOP proteins in PBMCs in the unimproved group, however, was not significantly changed relative to pretreatment levels. CONCLUSIONS ERS may play a significant role in the pathogenesis of SSNHL, and the responsiveness of the condition to GC-mediated mitigation of ERS may be one of the key factors that affect patient prognosis.
Subject(s)
Endoplasmic Reticulum Stress , Hearing Loss, Sensorineural/blood , Hearing Loss, Sensorineural/pathology , Leukocytes, Mononuclear/pathology , Activating Transcription Factor 4/metabolism , Adult , Down-Regulation/genetics , Endoplasmic Reticulum Stress/genetics , Eukaryotic Initiation Factor-2/metabolism , Female , Humans , Male , Transcription Factor CHOP/metabolism , Up-Regulation/genetics , eIF-2 Kinase/metabolismABSTRACT
Among different cancers, incidence and mortality of colorectal cancer (CRC) is one of the highest. KRAS mutation is one of the underlying features in the pathogenesis of CRC with CRC tumors harboring mutant KRAS exhibiting a more aggressive behavior compared to CRC tumors with wild type KRAS. We had earlier shown that the microRNA-143 (miR-143) replenishment not only chemosensitizers CRC cell line with mutant KRAS instead of wild-type KRAS gene, to paclitaxel-mediated cytotoxicity, but also inhibits cell migration and invasion ability. Hence, the study aimed to determine how miR-143 replenishment is inhibiting pre-metastatic behavior in CRC cells with mutant KRAS. Top ten mRNA targets of miR-143 as predicted by TargetScan were evaluated by qRT-PCR in LoVo cells which were performed mock transfection or miR-143 mimic transfection. Evaluation of the changes in cognate mRNA target(s) was done in 30 paired CRC tissue and tumor adjacent normal tissue specimens and in LoVo cells by western blot. Effect of the mRNA target on pro-metastatic behavior was assayed by gain- and loss-of-function studies using a combination of western blotting and in vitro cell proliferation and transwell migration/invasion assay in LoVo cells and in the normal colonic epithelium cell line FHC. In vivo effect of the cognate mRNA target on CRC metastasis was assayed by xenograft assay. Of the 10 predicted mRNA targets, FOSL2 (Pâ¯<â¯0.05) and IGFBP5 (Pâ¯>â¯0.05) was down regulated in LoVo cells transfected with the miR-143 mimic. FOSL2 mRNA levels were significantly downregulated in CRC tissue specimens compared with adjacent normal tissue (Pâ¯<â¯0.05). Immunoblot analysis showed that FOSL2, but not IGFBP5, protein expression is down regulated in LoVo cells after the miR-143 mimic transfection. FOSL2 overexpression in the normal colonic epithelial cell line FHC or siRNA-mediated silencing in LoVo cells induced and repressed, respectively, pro-mesenchymal cell features. Whereas manipulation of FOSL2 expression did not have any effect on cell proliferation rates, silencing its expression inhibited cell migration and invasion ability in vitro. In addition, silencing of FOSL2 expression in the LoVo cells can significantly inhibited invasion of hepatic, while no effect was found for tumorigenic potential. Our results suggest that FOSL2 is a critical regulator of CRC metastasis and might be an important marker for prognostic in CRC patients.
Subject(s)
Colorectal Neoplasms/pathology , Fos-Related Antigen-2/physiology , Animals , Cell Line , Cell Line, Tumor , Cell Movement , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Fos-Related Antigen-2/genetics , Fos-Related Antigen-2/metabolism , Humans , Mice, Nude , Neoplasm Invasiveness , Neoplasm MetastasisABSTRACT
Colorectal cancer (CRC) global incidence is one of the highest among cancers. The KRAS gene has been shown as a robust biomarker for poor prognosis and drug resistance. MicroRNA-143 (miR-143) and let-7 are families of tumor suppressor microRNAs that are often downregulated in CRC, especially with coexistent KRAS mutations. In order to evaluate if miR-143 and/or let-7b replenishment would re-sensitize CRC cells to paclitaxel treatment, we investigated in effect of miR-143 and let-7b replenishments on sensitivity to paclitaxel treatment in KRAS mutant LoVo and wild-type SW48 CRC cell lines. Our results showed that miR-143, but not let-7b, increased sensitization of KRAS mutant tumor cells to paclitaxel. Furthermore, transfection of miR-143, but not let-7b, mimic negatively regulated the expression of mutant but not wild-type KRAS. Combination of miR-143 mimic and paclitaxel induced the onset of apoptosis, and reverted in vitro metastatic properties (migration and invasion) in KRAS mutant tumor cells. MiR-143 thus can be used as a chemosensitizer for the treatment of KRAS mutant tumors and warrants further investigations in in vitro and pre-clinical in vivo models.
Subject(s)
Adenocarcinoma/pathology , Antineoplastic Agents, Phytogenic/pharmacology , Colorectal Neoplasms/pathology , Drug Resistance, Neoplasm/genetics , Genes, ras , MicroRNAs/genetics , Paclitaxel/pharmacology , Adenocarcinoma/genetics , Apoptosis/drug effects , Cell Division , Cell Line, Tumor , Colorectal Neoplasms/genetics , Humans , Mutation , Neoplasm Proteins/biosynthesis , Oncogene Protein p21(ras)/biosynthesis , RNA/genetics , TransfectionABSTRACT
Pseudomonas aeruginosa is a clinically common conditionally pathogenic bacterium, and the abuse of antibiotics has exacerbated its drug resistance in recent years. This has resulted in extensive reports about the usage of Pseudomonas aeruginosa phage as a novel antibacterial drug. In this study, we isolated a novel phage HZ2201 with a broad lytic spectrum. The lytic rate of this phage against Pseudomonas aeruginosa reached 78.38% (29/37), including 25 multi-drug- and carbapenem-resistant Pseudomonas aeruginosa strains. Transmission electron microscopy revealed that phage HZ2201 belongs to the class Caudoviricetes. Biological characterization showed that phage HZ2201 had an latent period of 40 min, a lytic period of 20 min, and a burst size of 440 PFU/cell, with improved tolerance to temperature and pH. Considering genomic analysis, the HZ2201 genome was a circular double-stranded DNA with a size of 45,431 bp and a guanine-cytosine (G + C) content of 52.16%, and contained 3 tRNAs. 27 of the 74 open reading frames (ORFs) annotated by the Rapid Annotation using Subsystem Technology (RAST) tool could be matched to the genomes of known functions, and no genes related to virulence and antibiotic resistance were found. The phylogenetic tree suggests that phage HZ2201 is highly related to the phage ZCPS1 and PaP3, and ORF57 and ORF17 are predicted to encode a holin and an endolysin, respectively. Cell lysis by HZ2201 proceeds through the holin-endolysin system, suggesting that it is a novel phage. Additionally, we demonstrated that phage HZ2201 has a high inhibitory capacity against Pseudomonas aeruginosa biofilms. The results of our study suggest that phage HZ2201 is a novel potential antimicrobial agent for treating drug-resistant Pseudomonas aeruginosa infection.
Subject(s)
Bacteriophages , Pseudomonas Phages , Bacteriophages/genetics , Pseudomonas aeruginosa/genetics , Phylogeny , Pseudomonas Phages/genetics , Genomics/methods , Genome, Viral , BiofilmsABSTRACT
Five new glycosides including mimenghuasu A and B (1-2), isolinarin (3), cyclocitralosides A and B (4-5), along with forty-seven known compounds were isolated from the flower buds of Buddleja officinalis. These structures were elucidated by extensive spectroscopic analysis (UV, IR, 1 D, 2 D NMR, and MS spectra). The anti-inflammatory activities of the isolated compounds were determined by enzyme-linked immunosorbent assay (ELISA) on the expression of TNF-α (LPS-activated RAW264.7 cells) and MTT experiment on LPS-induced HUVECs proliferation effects. Good suppressive effects on the expression of TNF-α were shown by 4 and 5 with IC50 values of 19.35 and 22.10 µM, respectively, compared to positive control indomethacin (IC50 16.40 µM). In addition to this, some isolated compounds exhibited excellent antioxidant activities including compounds 16, 18, 29, 39, and 47 (IC50 µM: 82.59, 72.94, 33.65, 46.67, and 20.81, respectively) with almost the same or stronger potency with reference to vitamin C as positive control (IC50 81.83 µM).
Subject(s)
Buddleja , Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry , Buddleja/chemistry , Flowers/chemistry , Lipopolysaccharides/pharmacology , Plant Extracts/chemistry , Tumor Necrosis Factor-alphaABSTRACT
BACKGROUND: To analyze mechanisms of action of glucocorticoid treatment for endoplasmic reticulum stress (ERS) in sensorineural hearing loss (SNHL), we aimed to evaluate the expression and activation status of the protein kinase RNA-like ER kinase (PERK)-C/EBP homologous protein (CHOP) pathway, which is the major pathway in the ERS. METHODS: In the present study, we established an in vitro ERS model using tunicamycin-treated hair-cell-like HEI-OC1 cells. The effect of dexamethasone on proliferation inhibition, apoptosis, and ATF4-CHOP pathway in HEI-OC1 cells was examined by CCK-8 assay, flow cytometry, western blotting, and reverse transcription PCR, respectively. RESULTS: In HEI-OC1 cells, dexamethasone was shown to significantly reduce the tunicamycin-induced expression of ATF4 and CHOP in the context of sustained viability and proliferation, a therapeutic effect that was reversible by co-treatment with a glucocorticoid antagonist. CONCLUSION: Dexamethasone can protect hair-cell-like HEI-OC1 cells from ERS damage, which may be one of the mechanisms of action for GCs in SNHL treatment.
ABSTRACT
We previously reported that dysregulation of histone deacetylase 2 (Hdac2) was associated with the prognosis of sudden sensorineural hearing loss. However, the underlying molecular mechanisms are poorly understood. In the present study, we developed an acute hearing loss animal model in guinea pigs by infusing lipopolysaccharides (LPS) into the cochlea and measured the expression of Hdac2 in the sensory epithelium. We observed that the level of Hdac2 was significantly decreased in the LPS-infused cochleae. The levels of apoptosis-inhibition genes Bcl-2 and Bcl-xl were also decreased in the cochlea and correlated positively with the levels of Hdac2. Caspase3 or TUNEL-positive spiral ganglion neurons, hair cells, and supporting cells were observed in the LPS-infused cochleae. These in vivo observations were recapitulated in cell culture experiments. Based on bioinformatics analysis, we found miR-204-5p was engaged in the regulation of Hdac2 on Bcl-2. Molecular mechanism experiments displayed that miR-204-5p could be regulated by Hdac2 through interacting with transcription factor Sp1. Taken together, these results indicated that the Hdac2/Sp1/miR-204-5p/Bcl-2 regulatory axis mediated apoptosis in the cochlea, providing potential insights into the progression of acute hearing loss. To our knowledge, the study describes a miRNA-related mechanism for Hdac2-mediated regulation in the cochlea for the first time.
ABSTRACT
A method for optimal design of a multilayer diffractive optical element (MLDOE) for dual-wide-waveband optical systems is presented with consideration of polychromatic integral diffraction efficiency (PIDE) and the weight factors of PIDE for each waveband. The design process and simulation of a MLDOE in mid-wave and long-wave IR are described, and the comparison of diffraction efficiency of the MLDOEs for different design wavelength pairs determined by different methods is given. This method can make the design process more rational and more reasonable and can give a better design result than that with the conventional design method.
ABSTRACT
Cisplatininduced cytotoxicity, such as nephrotoxicity, neurotoxicity and ototoxicity, restricts the clinical application of this compound. Panax notoginseng Saponins (PNS) exhibit potent free radical scavenging and antioxidant activity. PNS have been demonstrated to reduce cisplatininduced nephrotoxicity and neurotoxicity. The present study investigated the ability of PNS to protect the auditory HEIOC1 cell line against ototoxicity induced by cisplatin. PNS induced activation of the AKT/nuclear factor erythroid 2related factor 2 (Nrf2) signaling pathway. Following pretreatment with PNS, HEIOC1 cells were treated with cisplatin and cultured for 24 h. The viability of HEIOC1 cells was examined using a Cell Counting Kit8 assay. Double staining analysis was used to measure cell apoptosis. The ability of PNS to reduce reactive oxygen species (ROS) levels was assessed by flow cytometry. The levels of phosphorylated (p)AKT, heme oxygenase 1 (HO1), NAD(P)H quinone dehydrogenase 1 (NQO1), glutamatecysteine ligase catalytic (GCLC) and Nrf2 were measured by western blotting. HEIOC1 cells that were pretreated with PNS exhibited significantly increased cell viability compared with that noted in cells treated only with cisplatin. In addition, PNS suppressed the induction of apoptosis and ROS production following cisplatin treatment. The upregulation of NQO1, HO1 and GCLC expression in PNSpretreated cells was associated with pAKT levels and the activation of Nrf2. These findings suggested that PNS protected auditory cells against ototoxicity induced by cisplatin by activating AKT/Nrf2 signaling. PNS may serve as a potential candidate in regulating cisplatininduced cytotoxicity.
Subject(s)
Cisplatin/toxicity , Hair Cells, Auditory/cytology , Ototoxicity/metabolism , Panax notoginseng/chemistry , Saponins/pharmacology , Signal Transduction/drug effects , Animals , Cell Line , Cell Survival/drug effects , Gene Expression Regulation/drug effects , Hair Cells, Auditory/drug effects , Hair Cells, Auditory/metabolism , Male , Mice , Models, Biological , NF-E2-Related Factor 2/metabolism , Ototoxicity/drug therapy , Oxidative Stress/drug effects , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolismABSTRACT
Our previous work had shown that FOS-like antigen 2 (FOSL2) is regulated by miR-143-5p in colorectal cancer (CRC). Given that it has been shown by others that FOSL2 is also a target of miR-597-5p in breast adenocarcinoma, the objective of the current work was to determine whether FOSL2 is regulated by miR-597-5p in CRC and the role of miR-597-5p in CRC. MiR-597-5p expression was determined in RNA obtained from 30 paired samples of colon cancer and tumor adjacent normal tissue, as well as in the LoVo (CRC cell line) and FHC (normal colonic epithelial cells) by quantitative real time polymerase chain reaction (qRT-PCR). MiR-597-5p expression was significantly downregulated in both CRC tissue and LoVo cells. Reporter assays using wild-type and miR-597-5p seed mutant FOSL2 confirmed that FOSL2 is a bona fide target of miR-597-5p. Modulating miR-597-5p expression levels in FHC and LoVo cells using antagomir and mimic, respectively, impacted expression of epithelial and mesenchymal cell markers as well as in vitro migration and invasion, without any effect on cell proliferation, showing that miR-597-5p functions as a suppressor of epithelial to mesenchymal transition. Restoration of FOSL2 expression rescued pro-metastatic functional properties of LoVo cells conforming that effect of miR-597-5p was being mediated by targeting FOSL2. Xenograft assays in athymic nude mice showed that miR-597-5p mimic did not reduce tumor incidence or growth in LoVo cells. However, using a hepatic metastasis model showed that miR-597-5p mimic can significantly prevent hepatic metastatic nodule formation as well as FOSL2 expression in these metastatic nodules. Importantly, FOSL2 mRNA and miR-597-5p expression was found to be inversely correlated in an independent cohort of 21 CRC patients Cumulatively our results show that miR-597-5p functions as a suppressor of metastatic progression in CRC by targeting FOSL2. Replenishment of miR-597-5p can be a potential therapeutic target where its expression along with FOSL2 can serve as potential diagnostic markers in CRC.
ABSTRACT
In this work, hafnium oxide (HfO2) thin films are deposited on p-type Si substrates by remote plasma atomic layer deposition on p-type Si at 250 °C, followed by a rapid thermal annealing in nitrogen. Effect of post-annealing temperature on the crystallization of HfO2 films and HfO2/Si interfaces is investigated. The crystallization of the HfO2 films and HfO2/Si interface is studied by field emission transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and atomic force microscopy. The experimental results show that during annealing, the oxygen diffuse from HfO2 to Si interface. For annealing temperature below 400 °C, the HfO2 film and interfacial layer are amorphous, and the latter consists of HfO2 and silicon dioxide (SiO2). At annealing temperature of 450-550 °C, the HfO2 film become multiphase polycrystalline, and a crystalline SiO2 is found at the interface. Finally, at annealing temperature beyond 550 °C, the HfO2 film is dominated by single-phase polycrystalline, and the interfacial layer is completely transformed to crystalline SiO2.
ABSTRACT
Hafnium oxide (HfO2) thin films have attracted much attention owing to their usefulness in equivalent oxide thickness scaling in microelectronics, which arises from their high dielectric constant and thermodynamic stability with silicon. However, the surface passivation properties of such films, particularly on crystalline silicon (c-Si), have rarely been reported upon. In this study, the HfO2 thin films were deposited on c-Si substrates with and without oxygen plasma pretreatments, using a remote plasma atomic layer deposition system. Post-annealing was performed using a rapid thermal processing system at different temperatures in N2 ambient for 10 min. The effects of oxygen plasma pretreatment and post-annealing on the properties of the HfO2 thin films were investigated. They indicate that the in situ remote plasma pretreatment of Si substrate can result in the formation of better SiO2, resulting in a better chemical passivation. The deposited HfO2 thin films with oxygen plasma pretreatment and post-annealing at 500 °C for 10 min were effective in improving the lifetime of c-Si (original lifetime of 1 µs) to up to 67 µs.
ABSTRACT
The PPARD polymorphisms were shown to be associated with circulating lipoprotein metabolism in various diseases. We aimed to check the contribution of PPARD rs2016520 and lipid concentration to the risk of intracerebral hemorrhages (ICH) and brain tumors (BT) in Han Chinese. A total of 864 participants were included in the case-control study. The melting temperature shift (Tm-shift) method was used for rs2016520 genotyping. Under the recessive model, PPARD rs2016520 was shown to be associated with the risk of ICH (P=0.029, odds ratio (OR)=2.72), specifically in males (P=0.045, OR=3.98). Additionally, we also found that the levels of TC and LDL-C were significantly higher in participants with brain diseases than in the controls (TC: P<0.0001; LDL-C: P<0.0001). Significantly higher HDL-C and lower ApoA-I levels were observed in the male patients with brain diseases (HDL-C: P<0.0001; ApoA-I: P=0.008), in contrast of a higher TG level in female ICH (P=0.023). Subsequent interaction analysis between PPARD rs2016520 and lipoprotein metabolism showed that the LDL-C level was positively correlated with ICH in the rs2016520-AA carriers (P<0.0001), but not in the other genotype carriers (AG or GG, P=0.300). Our results showed that PPARD rs2016520 displayed a strong relationship with ICH risk in the male Han Chinese. The TC and LDL-C levels were positively higher in the patients with brain diseases than in the controls. The levels of TG, HDL-C and ApoA-I were shown to affect brain disease in a gender-dependent model. The genotype rs2016520-AA showed significant interaction with the circulating LDL-C levels in ICH.
Subject(s)
Brain Neoplasms/genetics , Cerebral Hemorrhage/genetics , Genetic Predisposition to Disease , Lipids/blood , PPAR delta/metabolism , Polymorphism, Single Nucleotide , Adult , Aged , Asian People , Case-Control Studies , Female , Gene Expression Regulation , Genotype , Humans , Lipid Metabolism/physiology , Male , Middle Aged , PPAR delta/genetics , Risk Factors , Sex CharacteristicsABSTRACT
BACKGROUND: MicroRNAs (miRNAs) function as essential posttranscriptional modulators of gene expression, and are involved in a wide range of physiologic and pathologic states, including cancer. Numerous miRNAs are deregulated in hepatocellular carcinoma (HCC). This study aimed to investigate the role of miR-27a in the development of HCC. METHODS: The expression of MiR-27a was measured by quantitative real-time polymerase chain reaction (qRT-PCR). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide was used to examine changes in the viability of HepG2, Bel-7402, Bel-7404 hepatoma cell lines associated with up-regulation or down-regulation of miR-27a. A dual-luciferase activity assay was used to verify a target gene of miR-27a. Immunohistochemistry, qRT-PCR, Western blotting analysis, and cell cycle and apoptosis flow cytometric assays were used to elucidate the mechanism by which miR-27a modulates liver cancer cell proliferation. RESULTS: The expression of miR-27a was signiï¬cantly increased in HCC tissues and HepG2, Bel-7402, Bel-7404 hepatoma cell lines (P < 0.05). We also found that the down-regulation of miR-27a in HepG2 cells dramatically inhibited proliferation, blocked the G1 to S cell cycle transition and induced apoptosis (P < 0.05). In addition, miR-27a directly targeted the 3'- untranslated region of peroxisome proliferator-activated receptor γ (PPAR-γ), and ectopic miR-27a expression suppressed PPAR-γ expression on the mRNA and protein levels. The rosiglitazone-induced overexpression of PPAR-γ attenuated the effect of miR-27a in HCC cells. CONCLUSIONS: Our findings suggested that miRNA-27a promoted HCC cell proliferation by regulating PPAR-γ expression. MiR-27a may provide a potential therapeutic strategy for HCC treatment.
Subject(s)
Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , MicroRNAs/physiology , PPAR gamma/metabolism , Cell Proliferation/genetics , Cell Proliferation/physiology , Gene Expression Regulation, Neoplastic , Hep G2 Cells , Humans , MicroRNAs/geneticsABSTRACT
CONCLUSION: The T-SPOT test for Mycobacterium tuberculosis infection (T-SPOT.TB) can be used for early diagnosis of laryngeal tuberculosis (TB). OBJECTIVE: The incidence of TB is increasing on a global scale. Laryngeal TB is the most common extrapulmonary form of TB and its early diagnosis is still difficult. This study investigated the performance of the interferon-γ release assay in the diagnosis of laryngeal TB. METHODS: A total of 83 patients with laryngeal neoplasms were confirmed to have laryngeal TB by pathology, acid-fast staining, and/or fluorescence quantitative PCR. In addition, 52 patients with vocal cord polyps were enrolled as the control group. Two groups underwent both T-SPOT.TB and tuberculin skin test (TST). RESULTS: T-SPOT.TB was positive in 75 cases in the laryngeal TB group and 4 cases in the control group, showing a sensitivity of 90.3% (75/83) and a specificity of 92.3% (48/52). The TST was positive in 42 cases and 20 cases, respectively, in these two groups. Obviously, TST and T-SPOT.TB were significantly different in terms of sensitivity when applied for detection of laryngeal TB (p < 0.05).