Publications by authors named "HaoRan Tang"

30 Publications

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Stochastic Collision Electrochemistry from Single G-Quadruplex/Hemin: Electrochemical Amplification and MicroRNA Sensing.

Anal Chem 2021 Mar 4. Epub 2021 Mar 4.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, P. R. China.

Stochastic collision electrochemistry is a hot topic in single molecule/particle research, which provides an opportunity to investigate the details of the single molecule/particle reaction mechanism that is always masked in ensemble-averaged measurements. In this work, we develop an electrochemical amplification strategy to monitor the electrocatalytic behavior of single G-quadruplex/hemin (GQH) for the reaction between hydrogen peroxide and hydroquinone (HQ) through the collision upon a gold nanoelectrode. The intrinsic peroxidase activities of single GQH were investigated by stochastic collision electrochemical measurements, giving further insights into understanding biocatalytic processes. Based on the unique catalytic activity of GQH, we have also designed a hybridization chain reaction strategy to detect miRNA-15 with good selectivity and sensitivity. This work provided a meaningful strategy to investigate the electrochemical amplification and the broad application for nucleic acid sensing at the single molecule/particle level.
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http://dx.doi.org/10.1021/acs.analchem.0c05055DOI Listing
March 2021

Heptacyclic S,N-Heteroacene-Based Near-Infrared Nonfullerene Acceptor Enables High-Performance Organic Solar Cells with Small Highest Occupied Molecular Orbital Offsets.

ACS Appl Mater Interfaces 2020 Nov 6;12(46):51776-51784. Epub 2020 Nov 6.

Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, People's Republic of China.

The reduction of energy offsets between donors and acceptors is a direct way to improve the open-circuit voltage () and overall performance of organic solar cells (OSCs). In this work, two nonfullerene acceptors (NFAs) (BDTBO-4F and BDTBO-4Cl) were synthesized, which were composed of a heptacyclic ,-heteroacene core and terminal units with halogen atoms, where the latter modulates the energy level of the frontier molecular orbital. Consequently, BDTBO-4Cl exhibited a deeper highest occupied molecular orbital level () and lowest unoccupied molecular orbital level () than BDTBO-4F. Moreover, these two NFAs exhibited high electron mobility and strong absorption at 700-900 nm. The polymer donor PM6 was combined with BDTBO-4F and BDTBO-4Cl, and the resulting OSCs exhibited outstanding power conversion efficiencies of 14.83% for the PM6:BDTBO-4F device and 13.87% for the PM6:BDTBO-4Cl device. More encouragingly, these OSCs exhibited efficient hole transfer from NFAs to PM6, despite small Δ values (<0.10 eV). These results prove that modulation of of acceptors to decrease Δ is an efficient strategy for high-performance OSCs.
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http://dx.doi.org/10.1021/acsami.0c19033DOI Listing
November 2020

Single gold nanoclusters: Formation and sensing application for isonicotinic acid hydrazide detection.

Talanta 2020 Dec 10;220:121376. Epub 2020 Jul 10.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, PR China. Electronic address:

Nano-sized electrodes have their special advantages for sensing applications, such as small overall dimension, fast response and low background current. In this work, single gold nanoclusters (AuNCs) were controllably prepared on single Pt nanoelectrode surface by electrodeposition method. The AuNCs covered Pt nanoelectrode (AuNCs/PtNE) had steady-state voltammetric response in redox species solution, which was similar to micro-/nano-sized electrodes. It was interesting to find isonicotinic acid hydrazide (INH, also known as isoniazid) showed good electrochemical response on AuNCs/PtNE surface, which had investigated carefully by square wave voltammetry (SWV) and chronoamperometry. Moreover, the prepared single AuNCs/PtNEs showed the capability for INH sensing with good sensitivity, reproducibility and selectivity, which was demonstrated for INH detection in human urine samples.
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http://dx.doi.org/10.1016/j.talanta.2020.121376DOI Listing
December 2020

Analytes Triggered Conformational Switch of i-Motif DNA inside Gold-Decorated Solid-State Nanopores.

ACS Sens 2020 07 10;5(7):2177-2183. Epub 2020 Jul 10.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, P. R. China.

The nanopore-based technique is a useful tool for single-molecule sensing and characterization. In this work, we have developed a new DNA-functionalized gold-modified nanopore, and analytes can induce the conformational switch of i-motif DNA formed on the inner surface of the nanopore. i-Motif DNA structure can be formed in the presence of silver ions (Ag), which will result in the change in surface charge and structure of the nanopore tip and ion current rectification (ICR) ratio. The i-motif DNA structure on nanopore surface will be destroyed after the addition of glutathione (GSH) due to the strong interaction of Ag-S bond, which results in the recovery of surface charge, steric hindrance, and ICR ratio. This analyte-triggered conformational switch of i-motif DNA can help us deeply understand the DNA technology inside single nanopore and will benefit the possible applications in an ultrasensitive detection and biological/chemical analysis.
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http://dx.doi.org/10.1021/acssensors.0c00798DOI Listing
July 2020

Nonfused Nonfullerene Acceptors with an A-D-A'-D-A Framework and a Benzothiadiazole Core for High-Performance Organic Solar Cells.

ACS Appl Mater Interfaces 2020 Apr 30;12(14):16531-16540. Epub 2020 Mar 30.

Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, P. R. China.

Nonfullerene acceptors (NFAs) have contributed significantly to the progress of organic solar cells (OSCs). However, most NFAs feature a large fused-ring backbone, which usually requires a tedious multiple-step synthesis, and are not applicable to commercial applications. An alternative strategy is to develop nonfused NFAs, which possess synthetic simplicity and facile tunability in optoelectronic properties and solid-state microstructures. In this work, we report two nonfused NFAs, BTCIC and BTCIC-4Cl, based on an A-D-A'-D-A architecture, which possess the same electron-deficient benzothiadiazole central core but different electron-withdrawing terminal groups. The optical properties, energy levels, and molecular crystallinities were finely tuned by changing the terminal groups. Moreover, a decent power conversion efficiency of 9.3 and 10.5% has been achieved by BTCIC and BTCIC-4Cl, respectively, by blending them with an appropriate polymer donor. These results demonstrate the potential of A-D-A'-D-A type nonfused NFAs for high-performance OSCs. Further development of nonfused NFAs will be very fruitful by employing appropriate building blocks and via side-chain optimizations.
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http://dx.doi.org/10.1021/acsami.0c01850DOI Listing
April 2020

Meta-analysis: The efficacy of metformin and other anti-hyperglycemic agents in prolonging the survival of hepatocellular carcinoma patients with type 2 diabetes.

Ann Hepatol 2020 May - Jun;19(3):320-328. Epub 2019 Dec 16.

Department of Hepatobiliary Surgery, the Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China; The Yunnan Provincial Clinical Center for Hepato-biliary-pancreatic Diseases, Kunming, Yunnan, China. Electronic address:

Introduction: This study aimed to compare the therapeutic efficacy of metformin and other anti-hyperglycemic agents in hepatocellular carcinoma (HCC) patients with type 2 diabetes (T2D).

Materials: A systematic electronic search on keywords including HCC and different anti-hyperglycemic agents was performed through electronic databases including Medline and EMBASE. The primary outcome was the overall survival (OS). The secondary outcomes were the recurrence-free survival (RFS) and progression-free survival (PFS).

Results: Six retrospective cohort studies were included for analysis: Four studies with curative treatment for HCC (618 patients with metformin and 532 patients with other anti-hyperglycemic agents) and two studies with non-curative treatment for HCC (92 patients with metformin and 57 patients with other anti-hyperglycemic agents). Treatment with metformin was associated with significantly longer OS (OR=2.62, 95%CI: 1.76-3.90; OR=3.14, 95%CI: 2.33-4.24; OR=3.31, 95%CI: 2.39-4.59, all P<0.00001) and RFS (OR=2.52, 95%CI: 1.84-3.44; OR=2.87, 95%CI: 2.15-3.84; all P<0.00001; and OR=2.26, 95%CI: 0.94-5.45, P=0.07) rates vs. those of other anti-hyperglycemic agents after curative therapies for HCC. However, both of the two studies reported that following non-curative HCC treatment, there were no significant differences in the OS and PFS rates between the metformin and non-metformin groups (I>50%).

Conclusions: Metformin significantly prolonged the survival of HCC patients with T2D after the curative treatment of HCC. However, the efficacy of metformin needs to be further determined after non-curative therapies for HCC patients with T2D.
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http://dx.doi.org/10.1016/j.aohep.2019.11.008DOI Listing
December 2019

Nanopore-based Strategy for Selective Detection of Single Carcinoembryonic Antigen (CEA) Molecules.

Anal Chem 2020 02 4;92(4):3042-3049. Epub 2020 Feb 4.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science , Anhui Normal University , Wuhu 241000 , P.R. China.

Nanopores have become one of the most important tools for single-molecule sensing, but the challenge for selective detection of specific biomolecules still exists. In this contribution, we develop a new technique for sensing carcinoembryonic antigen (CEA), one of the important cancer biomarkers, using solid-state nanopores as a tool. The method is based on the specific affinity between aptamer (Apt) modified magnetic FeO-Au nanoparticles (MNPs) and CEA, and the formed CEA-Apt-MNPs and remaining Apt-MNPs can transport the nanopores by applying a positive potential after magnetic separation. Due to the obvious particle size difference between CEA-Apt-MNPs and Apt-MPs, their corresponding blockage signals could be distinguished completely by the degree of the current decline. Moreover, the frequency of the blockage signals for CEA-Apt-MNPs is proportional to the concentration of CEA within certain limits, indicating that our designed nanopore sensing strategy can quantitatively detect CEA in complex samples. This work demonstrates that our designed nanopore-based strategy can be used for CEA sensing with good selectivity and sensitivity and also can be used to analyze other protein biomarkers for early diagnosis and monitoring of cancer, though the detection limit (0.6 ng/mL) is not relatively low. In future works, we plan to improve our detection limit by the improvement of the nanopipette preparation technology and detection method.
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http://dx.doi.org/10.1021/acs.analchem.9b04185DOI Listing
February 2020

Bioinformatics analysis of differentially expressed genes in hepatocellular carcinoma cells exposed to Swertiamarin.

J Cancer 2019 21;10(26):6526-6534. Epub 2019 Oct 21.

State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, PR China.

: To explore gene expression profiling in hepatocellular carcinoma (HCC) cells exposed to swertiamarin. : Cell viability, apoptosis and invasion were examined in HepG2 cells after swertiamarin treatment. Tumor growth of SK-Hep-1 cells xenografted in nude mice was monitored after swertiamarin treatment. Total RNA was isolated from HepG2 cells treated with swertiamarin for microarray analysis. The data of microarray were analyzed by bioinformatics. : Swertiamarin treatment decreased the viability and invasion while increased the apoptosis of HepG2 cells, and significantly inhibited the growth of SK-Hep-1 cells xenografted in nude mice. Pathway and biological process analysis of differentially expressed genes (DEGs) in swertiamarin treated HepG2 cells showed that PI3k-Akt was the most significant regulated pathway. 47 targets of swertiamarin were predicted by CGBVS while 21 targets were predicted by 3NN. Notably, 8 targets were predicted as the targets of swertiamarin by both programs, including two prominent targets JUN and STAT3. A large range of DEGs induced by swertiamarin could be regulated by JUN and STAT3. : Swertiamarin treatment led to significant changes in the expression of a variety of genes that modulate cell survival, cell cycle progression, apoptosis, and invasion. Moreover, most of these genes can be clustered into pathway networks such as PI3K, JUN, STAT3, which are predicted targets of swertiamarin. Further confirmation of these targets will reveal the anti-tumor mechanisms of swertiamarin and facilitate the development of swertiamarin as a novel agent for cancer prevention and treatment.
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http://dx.doi.org/10.7150/jca.33666DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6856900PMC
October 2019

The mechanism of aquatic photodegradation of organophosphorus sensitized by humic acid-Fe complexes.

J Hazard Mater 2020 02 19;384:121466. Epub 2019 Oct 19.

State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, People's Republic of China; State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, Chengdu University of Technology, Chengdu 610059, People's Republic of China; College of Environment and Ecology, Chengdu University of Technology, Chengdu 610059, People's Republic of China. Electronic address:

Organic phosphorus is an important source of eutrophication. In this study, to understand the mechanism of organophosphorus photodegradation, humic acid-Fe (HA-Fe) complexes were prepared as a sensitizer, and glyphosate (GP) was used as a substrate for photodegradation. The effects of the initial GP concentration, HA concentration, Fe concentration and microbial factors on photodegradation were investigated. The initial concentrations of GP, HA and Fe could significantly affect the degradation rate of GP. Phosphate is the main product of GP photodegradation. Based on the identification of the active species in the reaction process, t-butanol was found to have the most significant inhibitory effect on the degradation. The reaction rate after t-butanol treatment was reduced from 0.017 to 0.003. This confirmed that OH was the main oxidant in the system, which was also demonstrated by EPR spectroscopy. A possible mechanism of GP photodegradation sensitized by HA-Fe complexes was revealed for the first time. The HA-Fe complexes in the reaction system were photodegraded and oxidized to finally produce OH, which promotes GP photodegradation. This study facilitates understanding the phosphorus cycle in a water environment and provides a scientific basis for the restoration of eutrophic lakes.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121466DOI Listing
February 2020

Unique Voltammetry of Silver Nanoparticles: From Single Particle to Aggregates.

Anal Chem 2019 11 28;91(22):14188-14191. Epub 2019 Oct 28.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science , Anhui Normal University , Wuhu 241000 , P.R. China.

Understanding the electrooxidation process of metal nanoparticles (NPs) is very important because they have showed wide applications in electrocatalysis, sensing, and nanoelectronics. In this letter, we designed a strategy to investigate the anodic stripping voltammetry (ASV) of silver oxidation at single NP level and aggregation state by using gold single nanoelectrodes (SNEs) and ultramicroelectrodes. Results showed that the ASV peak potential and shape were significantly affected by the diameter and aggregation degree of the Ag NPs: symmetrical-peak shape, two-peak shape, and asymmetrical-peak shape appeared when Ag NPs changed from the single particle state to the large-aggregation state, and size-dependent ASVs for Ag NPs oxidation were also observed. These findings can help us deeply understand the metal NPs oxidation process and will benefit the related applications.
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http://dx.doi.org/10.1021/acs.analchem.9b03372DOI Listing
November 2019

2-Aminomethylene-5-sulfonylthiazole Inhibitors of Lysyl Oxidase (LOX) and LOXL2 Show Significant Efficacy in Delaying Tumor Growth.

J Med Chem 2020 03 4;63(5):2308-2324. Epub 2019 Sep 4.

Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Alderley Park, Macclesfield SK10 4TG, United Kingdom.

The lysyl oxidase (LOX) family of extracellular proteins plays a vital role in catalyzing the formation of cross-links in fibrillar elastin and collagens leading to extracellular matrix (ECM) stabilization. These enzymes have also been implicated in tumor progression and metastatic disease and have thus become an attractive therapeutic target for many types of invasive cancers. Following our recently published work on the discovery of aminomethylenethiophenes (AMTs) as potent, orally bioavailable LOX/LOXL2 inhibitors, we report herein the discovery of a series of dual LOX/LOXL2 inhibitors, as well as a subseries of LOXL2-selective inhibitors, bearing an aminomethylenethiazole (AMTz) scaffold. Incorporation of a thiazole core leads to improved potency toward LOXL2 inhibition via an irreversible binding mode of inhibition. SAR studies have enabled the discovery of a predictive 3DQSAR model. Lead AMTz inhibitors exhibit improved pharmacokinetic properties and excellent antitumor efficacy, with significantly reduced tumor growth in a spontaneous breast cancer genetically engineered mouse model.
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http://dx.doi.org/10.1021/acs.jmedchem.9b01112DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7073924PMC
March 2020

A simple strategy for the fabrication of gold-modified single nanopores and its application for miRNA sensing.

Chem Commun (Camb) 2019 Aug;55(69):10288-10291

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, P. R. China.

A simple nanopore modification and sensing strategy was developed for the detection of miRNAs. This preparation and sensing approach provides a quick, simple and facile tool for the detection of specific biomolecules with high sensitivity and selectivity, and may find a wide range of applications in bio-analysis.
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http://dx.doi.org/10.1039/c9cc04864bDOI Listing
August 2019

Removal of 2,4,6-trichlorophenol from water by Eupatorium adenophorum biochar-loaded nano-iron/nickel.

Bioresour Technol 2019 Oct 3;289:121734. Epub 2019 Jul 3.

State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu 610059, China; State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution SEKL-SW, Chengdu 610059, China; Chengdu University of Technology, College of Environment and Ecology, Chengdu 610059, China.

From the perspective of waste utilization, the invasive species, Eupatorium adenophorum was used to prepare biochar, which was then loaded with iron/nickel bimetals. Compared with pure biochar, the biochar-loaded nano-iron/nickel bimetals have a significant effect on the removal of 2,4,6-trichlorophenol (2,4,6-TCP) from water, and their degradation rate can be increased by 39.7%-71.6% under different conditions. Several factors can influence the removal of 2,4,6-TCP, including the load ratio, pH of the solution, concentration of 2,4,6-TCP, and coexisting ions in water (HCO, SO4, NO). Based on the density functional model (DET), Ni can activate H (produced in the reaction between nano-Fe and HO) to convert to H, which can then substitute Cl. The activation energy is 109.5 kJ/mol, indicating the reaction is easy to take place.
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http://dx.doi.org/10.1016/j.biortech.2019.121734DOI Listing
October 2019

Author Correction: Lysyl oxidase drives tumour progression by trapping EGF receptors at the cell surface.

Nat Commun 2019 Jul 18;10(1):3151. Epub 2019 Jul 18.

Molecular Oncology Group, Cancer Research UK Manchester Institute, University of Manchester, Manchester, M20 4BX, UK.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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http://dx.doi.org/10.1038/s41467-019-11220-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6639354PMC
July 2019

Selective Single Molecule Nanopore Sensing of microRNA Using PNA Functionalized Magnetic Core-Shell FeO-Au Nanoparticles.

Anal Chem 2019 06 7;91(12):7965-7970. Epub 2019 Jun 7.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science , Anhui Normal University , Wuhu 241000 , P. R. China.

Solid-state nanopores have been employed as useful tools for single molecule analysis due to their advantages of easy fabrication and controllable diameter, but selectivity is always a big concern for complicated samples. In this work, functionalized magnetic core-shell FeO-Au nanoparticles, which acted as a molecular carrier, were introduced into nanopore electrochemical system for microRNA sensing in complicated samples with high sensitivity, selectivity and signal-to-noise ratio (SNR). This strategy is based on the specific affinity between neutral peptide nucleic acids (PNA)-modified FeO-Au nanoparticles and negative miRNA, and the formation of negative FeO-Au-PNA-miRNA complex, which can pass through the nanopore by application of a positive potential and eliminate neutral FeO-Au-PNA complex. To detect miRNA in complicated samples, a magnet has been used to separate FeO-Au-PNA-miRNA complex with good selectivity. We think this is a facile and effective method for the detection of different targets at single molecular level, including nucleic acids, proteins, and other small molecules, which will open up a new approach in the nanopore sensing field.
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http://dx.doi.org/10.1021/acs.analchem.9b02025DOI Listing
June 2019

Amperometric sensing of hydrazine by using single gold nanopore electrodes filled with Prussian Blue and coated with polypyrrole and carbon dots.

Mikrochim Acta 2019 05 15;186(6):350. Epub 2019 May 15.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, People's Republic of China.

A nanoprobe for hydrazine sensing is described that is making use of a single gold nanopore electrode (SAuNPEs) that was modified by electro-deposition of Prussian Blue (PB) and then coated with a thin membrane of polypyrrole and carbon dots in order to enhance stability and catalytic activity. Best operated at a low potential of 0.3 V vs. Ag/AgCl, the nanosensor display good electrocatalytic activity towards the oxidation of hydrazine, with a linear response in the 0.5-80 μM hydrazine concentration range and a 0.18 μM detection limit (at S/N = 3). The method was applied to the determination of hydrazine in human urine. Graphical abstract Schematic presentation of the electrocatalytic oxidation of hydrazine using a single gold nanopore electrode that was modified by electro-deposition of Prussian Blue and then coated with a thin membrane of polypyrrole and carbon dots.
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http://dx.doi.org/10.1007/s00604-019-3486-6DOI Listing
May 2019

Anti-metastatic Inhibitors of Lysyl Oxidase (LOX): Design and Structure-Activity Relationships.

J Med Chem 2019 06 23;62(12):5863-5884. Epub 2019 May 23.

Cancer Research UK Centre for Cancer Therapeutics , The Institute of Cancer Research , 15 Cotswold Road , London SM2 5NG , United Kingdom.

Lysyl oxidase (LOX) is a secreted copper-dependent amine oxidase that cross-links collagens and elastin in the extracellular matrix and is a critical mediator of tumor growth and metastatic spread. LOX is a target for cancer therapy, and thus the search for therapeutic agents against LOX has been widely sought. We report herein the medicinal chemistry discovery of a series of LOX inhibitors bearing an aminomethylenethiophene (AMT) scaffold. High-throughput screening provided the initial hits. Structure-activity relationship (SAR) studies led to the discovery of AMT inhibitors with sub-micromolar half-maximal inhibitory concentrations (IC) in a LOX enzyme activity assay. Further SAR optimization yielded the orally bioavailable LOX inhibitor CCT365623 with good anti-LOX potency, selectivity, pharmacokinetic properties, as well as anti-metastatic efficacy.
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http://dx.doi.org/10.1021/acs.jmedchem.9b00335DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6937593PMC
June 2019

Single Ag Nanowire Electrodes and Single Pt@Ag Nanowire Electrodes: Fabrication, Electrocatalysis, and Surface-Enhanced Raman Scattering Applications.

Anal Chem 2019 Apr 13;91(7):4291-4295. Epub 2019 Mar 13.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science , Anhui Normal University , Wuhu , 241000 , P.R. China.

Silver nanowires (AgNWs) have received much attention due to their excellent optical, electrical, and conductive properties. In this work, we provided a new perspective for investigating the property of AgNWs from a single nanowire level. Single Ag nanowire electrodes and single Pt@Ag nanowire electrodes were fabricated by a laser-assisted pulling technique and galvanic replacement reaction (GRR). The radius, length, and metal ratio of the nanowires are tunable as needed. The prepared nanowire exhibited excellent electrocatalytic activity toward the methanol electro-oxidation and high sensitivity for monitoring the reduction of 4-nitrothiophenol by recording SERS spectra. This work will help us deeply understand the catalytic performance at the single nanowire level and open a new perspective for nanomaterials research.
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http://dx.doi.org/10.1021/acs.analchem.8b04610DOI Listing
April 2019

Dual-signal amplification strategy for miRNA sensing with high sensitivity and selectivity by use of single Au nanowire electrodes.

Biosens Bioelectron 2019 Apr 19;131:88-94. Epub 2019 Feb 19.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, PR China. Electronic address:

MicroRNAs (miRNAs) have been applied as biomarkers and better detection of their expression profiles plays important roles in early diagnosis of cancers. In this work, a simple dual-signal amplification strategy has been used to construct a novel nanosensor on single Au nanowire electrodes (SAuNWEs) for miRNA-16 detection based on the "signal-on" and "signal-off" features during hybridization/de-hybridization process. The ferrocene-labeled aptamer capture probe (Fc-CP-16) is designed to hybridize with thiolated methylene blue-labeled DNA probe (MB-CP) on SAuNWE to form duplex DNA, and the addition of miRNA-16 can lead to the dissociation of duplex structure due to the highly matched sequences between miRNA-16 and Fc-CP-16. The remaining MB-CP can thus tend to recover its hairpin structure at the presence of Mg through the hybridization of its complementary sequences. During this hybridization/de-hybridization process, the changes of Fc and MB oxidation peaks can be recorded, and there has a linear relationship between the sum of dual-signal changes (ΔI=ΔI+|ΔI|) and the logarithm of miRNA-16 concentrations, which can be used to detect miRNA-16. Including miRNA extraction, the dual-signal amplification strategy for miRNA sensing assay was carried out about 2 h for the detection in real samples. This novel nanosensor has small dimension, good selectivity, rapid response and regeneration ability, which can satisfy the need for early cancer marker detection in cells/organelles.
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http://dx.doi.org/10.1016/j.bios.2019.02.023DOI Listing
April 2019

Conjugated Polymers with Oligoethylene Glycol Side Chains for Improved Photocatalytic Hydrogen Evolution.

iScience 2019 Mar 15;13:33-42. Epub 2019 Feb 15.

Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, P. R. China.

Conjugated polymers are emerging as promising organic photocatalysts for hydrogen evolution from water. However, it is still very challenging for conjugated polymers to realize highly efficient photocatalytic hydrogen evolution. Herein, we demonstrate an efficient strategy of hydrophilic side chain functionalization to boost the hydrogen evolution rates of conjugated polymers. By functionalizing conjugated polymers with hydrophilic oligo (ethylene glycol) monomethyl ether (OEG) side chains, a 90-fold improvement in hydrogen evolution rate has been achieved than that of alkyl-functionalized conjugated polymer. It is found that the OEG side chains interact robustly with Pt co-catalysts, resulting in more efficient charge transfer. Moreover, OEG side chains in conjugated polymers can adsorb H from water, resulting in significantly lowered energy levels on the surfaces of conjugated polymers, which enables cascade energy levels and enhances charge separation and photocatalytic performance. Our results indicate that rational side-chain engineering could facilitate the design of improved organic photocatalysts for hydrogen evolution.
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http://dx.doi.org/10.1016/j.isci.2019.02.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6393733PMC
March 2019

Single Pt-Pd Bimetallic Nanoparticle Electrode: Controllable Fabrication and Unique Electrocatalytic Performance for the Methanol Oxidation Reaction.

Chemistry 2019 Apr 8;25(19):4935-4940. Epub 2019 Mar 8.

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, P.R. China.

Understanding the electrocatalytic activity at single nanoparticles/nanoclusters level is extremely important. In this work, a method for the electro-deposition of single Pt-Pd nanoparticles (NPs) is described using a single nanopore electrode as a template. The electro-deposition process was investigated carefully and the results show that the process is controlled by diffusion and electro-crystallization process, simultaneously, and the glass sheath property around the nanopore has a large impact on the formation of single Pt-Pd NPs due to the "edge effect". The prepared single Pt-Pd NPs exhibit excellent electrocatalytic activity in the methanol oxidation reaction, which can be used to screen electrocatalysts with high efficiency for utility in the energy field.
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http://dx.doi.org/10.1002/chem.201900076DOI Listing
April 2019

A signal amplification strategy and sensing application using single gold nanoelectrodes.

Analyst 2018 Dec;144(1):310-316

Anhui Key Laboratory of Chemo/Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, P. R. China.

In this work, a label-free electrochemical apta-nanosensor was fabricated on a single gold nanodisk electrode (AuNDE) for thrombin sensing with high sensitivity via a novel signal amplification strategy. This recognition platform was fabricated via self-assembly of helper DNA (HP-DNA), thrombin-binding aptamer (TBA) and gold nanoparticle (AuNP)-DNA complexes to form a sandwich structure on the AuNDE surface. A novel signal amplification strategy via designed AuNP-DNA complexes was introduced using Ru(NH3)63+ as the signal reporter based on the electrostatic interaction. In the presence of thrombin, the strong interaction between the TBA and target led to the dissociation of sandwich DNA complexes from the AuNDE, which resulted in the reduction current of Ru(NH3)63+. This proposed sensing platform showed a wide detection range of 0.1 pM-5 nM and a low detection limit of 0.02 pM. Considering the small overall dimensions and high sensitivity, this nanosensor can be potentially applied for bioanalysis in living biosystems.
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http://dx.doi.org/10.1039/c8an01474dDOI Listing
December 2018

Lysyl oxidase drives tumour progression by trapping EGF receptors at the cell surface.

Nat Commun 2017 04 18;8:14909. Epub 2017 Apr 18.

Molecular Oncology Group, Cancer Research UK Manchester Institute, University of Manchester, Manchester M20 4BX, UK.

Lysyl oxidase (LOX) remodels the tumour microenvironment by cross-linking the extracellular matrix. LOX overexpression is associated with poor cancer outcomes. Here, we find that LOX regulates the epidermal growth factor receptor (EGFR) to drive tumour progression. We show that LOX regulates EGFR by suppressing TGFβ1 signalling through the secreted protease HTRA1. This increases the expression of Matrilin2 (MATN2), an EGF-like domain-containing protein that traps EGFR at the cell surface to facilitate its activation by EGF. We describe a pharmacological inhibitor of LOX, CCT365623, which disrupts EGFR cell surface retention and delays the growth of primary and metastatic tumour cells in vivo. Thus, we show that LOX regulates EGFR cell surface retention to drive tumour progression, and we validate the therapeutic potential of inhibiting this pathway with the small molecule inhibitor CCT365623.
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http://dx.doi.org/10.1038/ncomms14909DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5399287PMC
April 2017

Discs large homolog 5 decreases formation and function of invadopodia in human hepatocellular carcinoma via Girdin and Tks5.

Int J Cancer 2017 07 9;141(2):364-376. Epub 2017 May 9.

Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Kunming Medical University, Kunming, China.

Invadopodium formation is a crucial early event of invasion and metastasis of hepatocellular carcinoma (HCC). However, the molecular mechanisms underlying regulation of invadopodia remain elusive. This study aimed to investigate the potential role of discs large homolog 5 (Dlg5) in invadopodium formation and function in HCC. We found that Dlg5 expression was significantly lower in human HCC tissues and cell lines than adjacent nontumor tissues and liver cells. Lower Dlg5 expression was associated with advanced stages of HCC, and poor overall and disease-free survival of HCC patients. Dlg5-silencing promoted epithelial-mesenchymal transition, invadopodium formation, gelatin degradation function, and invadopodium-associated invasion of HepG2 cells. In contrast, Dlg5 overexpression inhibited epithelial-mesenchymal transition, functional invadopodium formation, and invasion of SK-Hep1 cells. Both Girdin and Tks5, but not the Tks5 nonphosphorylatable mutant, were responsible for the enhanced invadopodium formation and invasion of Dlg5-silenced HepG2 cells. Furthermore, Dlg5 interacted with Girdin and interfered with the interaction of Girdin and Tks5. Dlg5 silencing promoted Girdin and Tks5 phosphorylation, which was abrogated by Girdin silencing and rescued by inducing shRNA-resistant Girdin expression. Moreover, Dlg5 overexpression significantly inhibited HCC intrahepatic and lung metastasis in vivo. Taken together, our data indicate that Dlg5 acts as a novel regulator of invadopodium-associated invasion via Girdin and by interfering with the interaction between Girdin and Tks5, which might be important for Tks5 phosphorylation in HCC cells. Conceivably, Dlg5 may act as a new biomarker for prognosis of HCC patients.
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http://dx.doi.org/10.1002/ijc.30730DOI Listing
July 2017

Scutellarin suppresses migration and invasion of human hepatocellular carcinoma by inhibiting the STAT3/Girdin/Akt activity.

Biochem Biophys Res Commun 2017 01 18;483(1):509-515. Epub 2016 Dec 18.

Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Kunming Medical University, Kunming, China. Electronic address:

Scutellarin is an active flavone from Erigeron breviscapine (vant) Hand Mass. This study aimed to investigate the potential role of scutellarin in migration and invasion of human hepatocellular carcinoma (HCC) cells and its possible mechanism. In comparison with the vehicle-treated controls, treatment with scutellarin (50 mg/kg/day) for 35 days significantly mitigated the lung and intrahepatic metastasis of HCC tumors in vivo. Scutellarin treatment significantly reduced HepG2 cell viability in a dose-dependent manner, and inhibited migration and invasion of HCC cells in vitro. Scutellarin treatment significantly reduced STAT3 and Girders of actin filaments (Girdin) expression, STAT3 and Akt phosphorylation in HCC cells. Introduction of STAT3 overexpression restored the scutellarin-downregulated Girdin expression, Akt activation, migration and invasion of HCC cells. Furthermore, induction of Girdin overexpression completely abrogated the inhibition of scutellarin on the Akt phosphorylation, migration and invasion of HCC cells. Scutellarin can inhibit HCC cell metastasis in vivo, and migration and invasion in vitro by down-regulating the STAT3/Girdin/Akt signaling.
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http://dx.doi.org/10.1016/j.bbrc.2016.12.114DOI Listing
January 2017

Nono, a Bivalent Domain Factor, Regulates Erk Signaling and Mouse Embryonic Stem Cell Pluripotency.

Cell Rep 2016 10;17(4):997-1007

Key Laboratory of Birth Defects, Children's Hospital and Key Laboratory of Epigenetics, Institutes of Biomedical Sciences, Fudan University, Shanghai 201102, China; Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Cellular and Genetic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China; Newborn Medicine Division, Boston Children's Hospital, Boston, MA 02115, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA. Electronic address:

Nono is a component of the para-speckle, which stores and processes RNA. Mouse embryonic stem cells (mESCs) lack para-speckles, leaving the function of Nono in mESCs unclear. Here, we find that Nono functions as a chromatin regulator cooperating with Erk to regulate mESC pluripotency. We report that Nono loss results in robust self-renewing mESCs with epigenomic and transcriptomic features resembling the 2i (GSK and Erk inhibitors)-induced "ground state." Erk interacts with and is required for Nono localization to a subset of bivalent genes that have high levels of poised RNA polymerase. Nono loss compromises Erk activation and RNA polymerase poising at its target bivalent genes in undifferentiated mESCs, thus disrupting target gene activation and differentiation. These findings argue that Nono collaborates with Erk signaling to regulate the integrity of bivalent domains and mESC pluripotency.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5086807PMC
http://dx.doi.org/10.1016/j.celrep.2016.09.078DOI Listing
October 2016

miR-448 suppressed gastric cancer proliferation and invasion by regulating ADAM10.

Tumour Biol 2016 Aug 8;37(8):10545-51. Epub 2016 Feb 8.

Department of Gastrointenstinal Surgery, The Second Affiliated Hospital of Kunming Medical University, Kunming, 650101, Yunnan, China.

MicroRNAs (miRNAs) are a class of short, noncoding RNAs that act a crucial role in tumor development. Previous studies showed that miR-448 expression was deregulated in many tumors. However, the role of miR-448 in gastric cancer (GC) remains unknown. In our study, we demonstrated that miR-448 expression was downregulated in GC tissues compared with the corresponding nontumor tissues. We also showed that miR-448 expression was downregulated in GC cell lines. Ectopic expression of miR-448 suppressed GC cell proliferation, colony formation, and invasion. Moreover, we identified A Disintegrin And Metalloproteinases 10 (ADAM10) as a direct target gene of miR-448 in GC cell. ADAM10 expression was upregulated in GC tissues and cells. Furthermore, the expression level of miR-448 was negatively correlated with the expression level of ADAM10 in GC tissues. Moreover, ADAM10 overexpression rescued the effect of miR-448-mediated GC cell proliferation, colony formation, and invasion. These results demonstrated that miR-448 might play as a tumor suppressor miRNA partly through targeting ADAM10 expression.
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http://dx.doi.org/10.1007/s13277-016-4942-0DOI Listing
August 2016

Finding gastric cancer related genes and clinical biomarkers for detection based on gene-gene interaction network.

Math Biosci 2016 06 14;276:1-7. Epub 2015 Dec 14.

Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Kunming Medical University, Kunming 650101, Yunnan, China.

Background/objective: Gastric cancer (GC) is the second leading cause of death resulted from cancer globally. The most common cause of GC is the infection of Helicobacter pylori, approximately 11% of cases are caused by genetic factors. The objective of this study was to develop an effective computational method to meaningfully interpret these GC-related genes and to predict potential prognostic genes for clinical detection.

Methods: We employed the shortest path algorithm and permutation test to probe the genes that have relationship with known GC genes in gene-gene interaction network. We calculated the enrichment scores of gene ontology and pathways of gastric cancer related genes to characterize these genes in terms of molecular features. The optimal features that primly representing the gastric cancer related genes were selected using Random Forest classification and incremental feature selection. Random Forest classification was also used for the prediction of the novel gastric cancer related genes based on the selected features and the identification of novel prognostic genes based on the expression of genes.

Results: Based on the shortest path analysis of 36 known GC genes, 39 genes occurring in shortest path were identified as GC-related genes. In subsequent classification, 4153 gene ontology terms and 157 pathway terms were identified as the optimal features to depict these gastric cancer related genes. Based on them, a total of 886 genes were predicted as related genes. These 886 genes could serve as expression biomarkers for clinical detection and they achieved a 100% accuracy for distinguishing gastric cancer from a case-control dataset, better than any of 886 random selected genes did.

Conclusion: By analyzing the features of known GC-related genes, we employed a systematic method to predict gastric cancer related genes and novel prognostic genes for accurate clinical detection.
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http://dx.doi.org/10.1016/j.mbs.2015.12.001DOI Listing
June 2016

Resistance to BRAF inhibitors induces glutamine dependency in melanoma cells.

Mol Oncol 2016 Jan 20;10(1):73-84. Epub 2015 Aug 20.

Molecular Oncology Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK. Electronic address:

BRAF inhibitors can extend progression-free and overall survival in melanoma patients whose tumors harbor mutations in BRAF. However, the majority of patients eventually develop resistance to these drugs. Here we show that BRAF mutant melanoma cells that have developed acquired resistance to BRAF inhibitors display increased oxidative metabolism and increased dependency on mitochondria for survival. Intriguingly, the increased oxidative metabolism is associated with a switch from glucose to glutamine metabolism and an increased dependence on glutamine over glucose for proliferation. We show that the resistant cells are more sensitive to mitochondrial poisons and to inhibitors of glutaminolysis, suggesting that targeting specific metabolic pathways may offer exciting therapeutic opportunities to treat resistant tumors, or to delay emergence of resistance in the first-line setting.
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http://dx.doi.org/10.1016/j.molonc.2015.08.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4717845PMC
January 2016

Loss of Scar/WAVE complex promotes N-WASP- and FAK-dependent invasion.

Curr Biol 2013 Jan 27;23(2):107-17. Epub 2012 Dec 27.

The Beatson Institute for Cancer Research, Switchback Road, Glasgow G61 1BD, UK.

Background: The Scar/WAVE regulatory complex (WRC) drives lamellipodia assembly via the Arp2/3 complex, whereas the Arp2/3 activator N-WASP is not essential for 2D migration but is increasingly implicated in 3D invasion. It is becoming ever more apparent that 2D and 3D migration utilize the actin cytoskeletal machinery differently.

Results: We discovered that WRC and N-WASP play opposing roles in 3D epithelial cell migration. WRC depletion promoted N-WASP/Arp2/3 complex activation and recruitment to leading invasive edges and increased invasion. WRC disruption also altered focal adhesion dynamics and drove FAK activation at leading invasive edges. We observed coalescence of focal adhesion components together with N-WASP and Arp2/3 complex at leading invasive edges in 3D. Unexpectedly, WRC disruption also promoted FAK-dependent cell transformation and tumor growth in vivo.

Conclusions: N-WASP has a crucial proinvasive role in driving Arp2/3 complex-mediated actin assembly in cooperation with FAK at invasive cell edges, but WRC depletion can promote 3D cell motility.
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http://dx.doi.org/10.1016/j.cub.2012.11.059DOI Listing
January 2013