Efficacy of Cetuximab in Nasopharyngeal Carcinoma Patients Receiving Concurrent Cisplatin-Radiotherapy: A Meta-Analysis.

Background: Nasopharyngeal carcinoma (NPC) is a malignant neoplasm of the nasopharyngeal epithelium. Concurrent chemoradiotherapy has been established as a standard treatment for locoregional NPC, and cisplatin is a common agent in NPC treatment. Cetuximab is a monoclonal antibody against epidermal growth factor receptor. This meta-analysis was performed to evaluate the curative effectiveness and survival outcomes of cetuximab in NPC patients who received concurrent cisplatin-radiotherapy. Methods: PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure (CNKI), Wan Fang, and China Biology Medicine disc (CBM) were used to search publications studying on concurrent chemoradiotherapy and/or cetuximab in NPC. The qualities of included RCTs were assessed by the Newcastle-Ottawa Scale. STATA 14.0 was used to conduct the statistical analysis. Results: In total, 17 trials with 2066 patients were included in this meta-analysis. The results from this study show that cetuximab improved the therapy efficacy in NPC patients who received concurrent cisplatin-radiotherapy. Cetuximab cotreatment improved the complete response (RR = 1.92, 95% CI [1.61, 2.30]), and reduced stable disease (RR = 0.67, 95% CI [0.51, 0.88]) as well as progression disease (RR = 0.24, 95% CI [0.15, 0.40]). Besides, it also improved the overall survival (RR = 1.10, 95% CI [1.02, 1.18]), disease-free survival (RR = 1.09, 95% CI [1.03, 1.15]), metastasis-free survival (RR = 1.06, 95% CI [1.01, 1.11]), and relapse-free survival (RR = 1.04, 95% CI [1.01, 1.07]) in NPC patients. Conclusions: Cetuximab could improve the curative efficacy and survival outcomes of NPC patients who underwent concurrent cisplatin-radiotherapy. However, all the trials included were conducted in China; thus, the quality of the trials in this study remains doubtful. More high-quality RCTs should be included in further relevant studies.

LncRNA LOC285758 Induced Non-Small Cell Lung Cancer Development through Up-Regulating CDK6 by Sponge Adsorption of miRNA-204.

Background: Non-coding RNA played one pivotal role in NSCLC in terms of pathogenesis and progression. We aimed to determine the LncRNA, which can be one new potential target for NSCLC treatment and its possible mechanisms from Jan 2017 to Aug 2020. Methods: Gene LOC285758, which produced new cells in tumor cellular system, was knocked out. Its specific effects were tested in terms of cellular phenotype. LOC285758 was chosen to target for miRNA as well as downstream mRNA targeted by miRNA, which verified the combination predicted before. Specific impacts brought from miRNA on NSCLC cells were examined. At last, dynamic impacts produced through miRNA and LOC285758 on mRNA expression and NSCLC cellular phenotype were examined. Results: LOC285758 expression was up-regulated in tissues and cells from NSCLC. Knocking out gene LOC285758 could repress cellular survival and migration of A549 and H292 cells. miRNA-204 was repressed via LOC285758 targeting. miRNA-204 over-expressing repressed invasion ability of NSCLC cells and CDK6 targeted by miRNA-204. CDK6 knocking out suppressed survival and migration of NSCLC cells. The influence brought from gene LOC285758 knocking out could be reversed through suppressing miRNA-204, causing up-regulated CDK6 as well as LOC285758 expression in NSCLC tissues. miRNA-204 was negatively correlated with CDK6 as well as LOC285758, respectively. Nonetheless, CDK6 possessed the positive relationship with LOC285758. Conclusion: An axis of lncRNA LOC285758/miRNA-204/CDK6 can modulate NSCLC cells in terms of migration as well as survival.

MicroRNA-497/fibroblast growth factor-23 axis, a predictive indictor for decreased major adverse cardiac and cerebral event risk in end-stage renal disease patients who underwent continuous ambulatory peritoneal dialysis.

OBJECTIVE: This study aimed at exploring the correlation of microRNA (miR)-497/fibroblast growth factor-23 (FGF-23) axis with major adverse cardiac and cerebral event (MACCE) occurrence in end-stage renal disease (ESRD) patients who underwent continuous ambulatory peritoneal dialysis (CAPD). METHODS: Totally, 360 ESRD patients who underwent CAPD were enrolled. Their plasma samples were collected to detect miR-497 expression by real-time quantitative polymerase chain reaction, and FGF-23 level by enzyme-linked immunosorbent assay. All patients were followed up for 36 months, and the occurrence of MACCE during the follow-up was documented. RESULTS: MiR-497 expression negatively correlated with FGF-23 level in ESRD patients who underwent CAPD (P < .001). The MACCE occurrence rate at 1, 2, and 3-year was 5.6%, 11.9%, and 15.0%, respectively. Furthermore, miR-497/FGF-23 axis high level (P < .001) and miR-497 high expression (P = .034) correlated with reduced accumulating MACCE occurrence, whereas FGF-23 high level (P = .008) correlated with increased accumulating MACCE occurrence. Forward stepwise multivariate Cox's regression disclosed that miR-497/FGF-23 axis high level (P = .008) was an independent predictive factor for lower accumulating MACCE occurrence, whereas age (≥55 years) (P < .001), body mass index (≥21.7 kg/m2 ) (P = .006), peritoneal dialysis duration (≥61.0 months) (P < .001), C-reactive protein (≥4.7 mg/L) (P = .001), serum uric acid (≥409.4 µmol/L) (P = .009), ß-fibrinogen (≥5.8 mmol/L) (P < .001), and low-density lipoprotein cholesterol (≥2.7 mmol/L) (P = .003) were independent factors for predicting higher accumulating MACCE occurrence. CONCLUSION: MiR-497/FGF-23 axis holds clinical significance for predicting attenuated MACCE risk in ESRD patients who underwent CAPD.

Multiplexed detection of microRNAs by a competitive DNA microarray-based resonance light scattering assay.

The reliable detection and monitoring of microRNAs (miRNAs) are of great significance for gaining a better understanding of the functions of miRNAs in a wide range of biological processes. In this work, a competitive DNA microarray-based resonance light scattering (RLS) assay has been developed for the multiplexed detection of miRNAs with relatively high sensitivity and selectivity. After one-step competition hybridization reactions of miRNAs and multiple single strand DNA (ssDNA) conjugated gold nanoparticles (ssDNAsn@GNPs) with immobilized ssDNA probes on the dendrimer-modified slide, the captured ssDNAsn@GNPs are further enlarged through silver deposition. The silver enlarged ssDNAsn@GNPs can generate strong RLS under white light excitation. The simultaneous detection of multiple miRNAs can be easily achieved by monitoring the RLS signal changes of microarrays. In the proof of concept experiment, eight miRNA let-7 family members are detected with high specificity down to 0.2 pM, 0.8 pM, 0.2 pM, 0.2 pM, 0.2 pM, 0.8 pM, 0.8 pM, and 0.8 pM for miRNA let-7a to 7g, and 7i, respectively. Furthermore, the expression levels of eight miRNA let-7 family members in the total RNA extracts from five cell lines have been evaluated, and satisfactory results are obtained.

Development of Sphere-Polymer Brush Hierarchical Nanostructure Substrates for Fabricating Microarrays with High Performance.

In this work, a sphere-polymer brush hierarchical nanostructure-modified glass slide has been developed for fabricating high-performance microarrays. The substrate consists of a uniform 160 nm silica particle-self-assembled monolayer on a glass slide with a postcoated poly(glycidyl methacrylate) (PGMA) brush layer (termed PGMA@3D(160) substrate), which can provide three-dimensional (3D) polymer brushes containing abundant epoxy groups for directly immobilizing various biomolecules. As a typical example, the interactions of three monosaccharides (4-aminophenyl ß-d-galactopyranoside, 4-aminophenyl ß-d-glucopyranoside, and 4-aminophenyl α-d-mannopyranoside) with two lectins (biotinylated ricinus communis agglutinin 120 and biotinylated concanavalin A from Canavalia ensiformis) have been assessed by PGMA@3D(160) substrate-based carbohydrate microarrays. The carbohydrate microarrays show good selectivity, strong multivalent interaction, and low limit of detection (LOD) in the picomolar range without any signal amplification. Furthermore, the proposed sphere-polymer brush hierarchical nanostructure substrates can be easily extended to fabricate other types of microarrays for DNA and protein detection. PGMA@3D(160) substrate-based microarrays exhibit higher reaction efficiencies and lower LODs (by at least 1 order of magnitude) in comparison to those of two-dimensional microarrays, which are fabricated on planar epoxy substrates, making it a promising platform for bioanalytical and biomedical applications.

Poly(glycidyl methacrylate-co-2-hydroxyethyl methacrylate) Brushes as Peptide/Protein Microarray Substrate for Improving Protein Binding and Functionality.

We developed a three-dimensional (3D) polymer-brush substrate for protein and peptide microarray fabrication, and this substrate was facilely prepared by copolymerization of glycidyl methacrylate (GMA) and 2-hydroxyethyl methacrylate (HEMA) monomers via surface-initiated atom transfer radical polymerization (SI-ATRP) on a glass slide. The performance of obtained poly(glycidyl methacrylate-co-2-hydroxyethyl methacrylate) (P(GMA-HEMA)) brush substrate was assessed by binding of human IgG with rabbit antihuman IgG antibodies on a protein microarray and by the determination of matrix metalloproteinase (MMP) activities on a peptide microarray. The P(GMA-HEMA) brush substrate exhibited higher immobilization capacities for proteins and peptides than those of a two-dimensional (2D) planar epoxy slide. Furthermore, the sensitivity of the P(GMA-HEMA) brush-based microarray on rabbit antihuman IgG antibody detection was much higher than that of its 2D counterpart. The enzyme activities of MMPs were determined specifically with a low detection limit of 6.0 pg mL(-1) for MMP-2 and 5.7 pg mL(-1) for MMP-9. By taking advantage of the biocompatibility of PHEMA, the P(GMA-HEMA) brush-based peptide microarray was also employed to evaluate the secretion of MMP-2 and MMP-9 by cells cultured off the chip or directly on the chip, and satisfactory results were obtained.

Surface ligation-based resonance light scattering analysis of methylated genomic DNA on a microarray platform.

DNA methylation is a crucial epigenetic modification and is closely related to tumorigenesis. Herein, a surface ligation-based high throughput method combined with bisulfite treatment is developed for analysis of methylated genomic DNA. In this method, a DNA microarray is employed as a reaction platform, and resonance light scattering (RLS) of nanoparticles is used as the detection principle. The specificity stems from allele-specific ligation of Taq DNA ligase, which is further enhanced by improving the fidelity of Taq DNA ligase in a heterogeneous reaction. Two amplification techniques, rolling circle amplification (RCA) and silver enhancement, are employed after the ligation reaction and a gold nanoparticle (GNP) labeling procedure is used to amplify the signal. As little as 0.01% methylated DNA (i.e. 2 pmol L(-1)) can be distinguished from the cocktail of methylated and unmethylated DNA by the proposed method. More importantly, this method shows good accuracy and sensitivity in profiling the methylation level of genomic DNA of three selected colonic cancer cell lines. This strategy provides a high throughput alternative with reasonable sensitivity and resolution for cancer study and diagnosis.

Development of a sandwiched microarray platform for studying the interactions of antibiotics with Staphylococcus aureus.

It still confronts an outstanding challenge to screen efficient antibacterial drugs from millions of potential antibiotic candidates. In this regard, a sandwiched microarray platform has been developed to culture live bacteria and carry out high-throughput screening antibacterial drugs. The optimized lectin-hydrogel microarray can be used as an efficient bacterial capturing and culturing platform, which is beneficial to identify spots and collect data. At the same time, a matching drug-laden polyacrylamide microarray with Luria-Bertani (LB) culture medium can be generated automatically and accurately by using a standard non-contacting procedure. A large number of microscale culture chambers (more than 100 individual samples) between two microarrays can be formed by linking two aligned hydrogel spots using LB culture medium, where live bacteria can be co-cultured with drug candidates. Using Staphylococcus aureus (S. aureus) and four well-known antibiotics (amoxicillin, vancomycin, streptomycin and chloramphenicol) as model system, the MIC (minimum inhibitory concentration) values of the antibiotics can be determined by the drug induced change of bacterial growth, and the results demonstrate that the MIC values of amoxicillin, vancomycin and streptomycin are 1.7 µg mL(-1), 3.3 µg mL(-1) and 10.3 µg mL(-1), respectively.

A portable optical waveguide resonance light-scattering scanner for microarray detection.

In the present work, a portable and low-cost planar waveguide based resonance light scattering (RLS) scanner (termed as: PW-RLS scanner) has been developed for microarray detection. The PW-RLS scanner employs a 2 × 4 white light emitting diode array (WLEDA) as the excitation light source, a folded optical path with a complementary metal oxide semiconductor (CMOS) as the signal/image acquisition device and stepper motors with gear drives as the mechanical drive system. The biological binding/recognizing events on the microarray can be detected with an evanescent waveguide-directed illumination and light-scattering label (e.g., nanoparticles) while the microarray slide acts as an evanescent waveguide substrate. The performance of the as-developed PW-RLS scanner has been evaluated by analyzing type 2 diabetes mellitus (T2DM) risk genes. Highly selective and sensitive (less than 1% allele frequency at the attomole-level) T2DM risk gene detection is achieved using single-stranded DNA functionalized gold nanoparticles (ssDNA-GNPs) as detection probes. Additionally, the successful simultaneous analysis of 15 T2DM patient genotypes suggests that the device has great potential for the realization of a personalized diagnostic test for a given disease or patient follow-up.

The Peptide Microarray-Based Resonance Light Scattering Assay for Sensitively Detecting Intracellular Kinase Activity.

The peptide microarray technology is a robust, reliable, and efficient technique for large-scale determination of enzyme activities, and high-throughput profiling of substrate/inhibitor specificities of enzymes. Here, the activities of cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) in different cell lysates have been detected by a peptide microarray-based resonance light scattering (RLS) assay with gold nanoparticle (GNP) probes. Highly sensitive detection of PKA activity in 0.1 µg total cell proteins of SHG-44 (human glioma cell) cell lysate (corresponding to 200 cells) is achieved by a selected peptide substrate. The experimental results also demonstrate that the RLS assay can be employed to evaluate the chemical regulation of intracellular kinase activity.

A label-free electrochemical impedance aptasensor for cylindrospermopsin detection based on thionine-graphene nanocomposites.

It is important to develop methods to determine cylindrospermopsin (CYN) at trace levels since CYN is a kind of widespread cyanobacterial toxin in water sources. In this study, a label-free impedimetric aptasensor has been fabricated for detecting CYN. In this case, the amino-substituted aptamer of CYN was covalently grafted onto the surface of the thionine-graphene (TH-G) nanocomposite through the cross-linker glutaraldehyde (GA). The reaction of the aptamer with CYN was monitored by electrochemical impedance spectroscopy because the CYN induced conformation change of the aptamer can cause a remarkable decrease of the electron transfer resistance. Under optimum conditions, the aptasensor exhibits high sensitivity and a low detection limit for CYN determination. The CYN can be quantified in a wide range of 0.39 to 78 ng mL(-1) with a good linearity (R(2) = 0.9968) and a low detection limit of 0.117 ng mL(-1). In addition, the proposed aptasensor displays excellent stability, reusability and reproducibility.

Fabricating three-dimensional carbohydrate hydrogel microarray for lectin-mediated bacterium capturing.

Herein, a three-dimensional carbohydrate modified polyacrylamide hydrogel microarray (3D carbohydrate hydrogel microarray) has been fabricated and employed as micro-reactor for capturing Escherichia coli (E. coli) by multivalent binding of concanavalin A (Con A) with O-antigen on the cellular surface of E. coli and immobilized monosaccharides on hydrogel spot, and the interactions of type 1 fimbriae of E. coli with immobilized monosaccharides. Because of the transparent performance of polyacrylamide hydrogel, the captured E. coli can be directly observed by a conventional microscope under a bright-field mode. The experimental result demonstrates that α-D-mannopyranoside (Man-α) modified hydrogel surface shows high efficiency of E. coli capturing. The 3D Man-α hydrogel microarray-based assay shows reasonable low detection limit (1.0×10(4) cells/mL) and large dynamic range (1.0×10(5) to 1.0×10(9)cells/mL) for detecting E. coli. In addition, bacterial adhesion inhibition assay has been demonstrated by the interactions of E. coli with ten saccharides, and satisfactory results have been obtained.

Preparation of graphene oxide-silver nanoparticle nanohybrids with highly antibacterial capability.

A simple method based on electrostatic interactions was utilized to assemble silver nanoparticles (AgNPs) to graphene oxide (GO) sheets. This method allows conjugation of AgNPs with desired morphologies (densities, sizes and shapes) onto GO. In this process, poly(diallyldimethylammonium chloride) (PDDA) was introduced as an adhesive agent. The as-prepared graphene oxide-AgNPs composites (GO-AgNPs) have enhanced colloid stability and photo-stability than that of AgNPs. After conjugating to GO sheets, the antibacterial activities of AgNPs against Gram negative (G-) bacterial strain (Escherichia coli, E. coli) and Gram positive (G+) bacterial strain (Bacillus subtilis, B. subtilis) have been improved significantly. The antibacterial activity of GO-AgNPs is dependent on the size of AgNPs, i.e. the small AgNPs modified GO sheets show more effective antibacterial capability than that of large AgNPs modified GO sheets. Compared with AgNPs, the enhanced antibacterial activity of GO-AgNPs might not only be due to high stability of AgNPs anchored on GO sheets, but also the positive charged surface of hybrids which increases the electrostatic interaction of bacterial cell membrane with nanohybrids.

Sensitive detection of protein kinase A activity in cell lysates by peptide microarray-based assay.

In the present work, the activities of protein kinase A (PKA) in cell lysates have been detected by a peptide microarray-based resonance light scattering assay with gold nanoparticle probes. Highly sensitive detection of PKA activity in 0.1 µg total cell proteins of SHG-44 cell lysate (corresponding to 200 cells) is achieved by a selected peptide substrate. The experimental results also demonstrate that the assay can be employed to evaluate expression levels of PKA activity in different cell lines and chemical (e.g., Forskolin )-mediated PKA activity fluctuation in living cells. In addition, PKA inhibition by the inhibitor (H89) is shown, suggesting the potential for screening PKA inhibitors at the living cell level.

Nanoparticle-based systems for T(1)-weighted magnetic resonance imaging contrast agents.

Because magnetic resonance imaging (MRI) contrast agents play a vital role in diagnosing diseases, demand for new MRI contrast agents, with an enhanced sensitivity and advanced functionalities, is very high. During the past decade, various inorganic nanoparticles have been used as MRI contrast agents due to their unique properties, such as large surface area, easy surface functionalization, excellent contrasting effect, and other size-dependent properties. This review provides an overview of recent progress in the development of nanoparticle-based T1-weighted MRI contrast agents. The chemical synthesis of the nanoparticle-based contrast agents and their potential applications were discussed and summarized. In addition, the recent development in nanoparticle-based multimodal contrast agents including T1-weighted MRI/computed X-ray tomography (CT) and T1-weighted MRI/optical were also described, since nanoparticles may curtail the shortcomings of single mode contrast agents in diagnostic and clinical settings by synergistically incorporating functionality.

Preparation and application of thionin-bridged graphene-gold nanoparticle nanohybrids.

A universal approach for controllable assembly of gold nanoparticles (AuNPs) on chemically reduced graphene oxide (rGO) is presented. AuNPs were conjugated to thionin (TH)-modified rGO through formation of amide bonds. TH has been used as a bridge to link the AuNPs with rGO in this work. The as-prepared AuNP-TH-rGO nanohybrids were characterized by means of transmission electron microscopy (TEM), ultraviolet-visible-near infrared spectroscopy (UV-vis-NIR), X-ray photoelectron spectroscopy (XPS), Fourier Transform infrared (FTIR) and Raman measurements. The experimental results indicate that the particle size and distribution density of AuNPs on the graphene sheets can be well controlled by adjusting the original size and concentration of AuNPs in the reaction mixture. The AuNPs on the surface of graphene were stable under harsh treatment (e.g., acid, alkaline or ultrasonic treatment). Ligand exchange experimental results show that the AuNP-TH-rGO can be easily further functionalized by sulfhydryl-containing ligands. Compared to poly-l-lysine (PLL) coated rGO, PLL coated AuNP-TH-rGO shows higher NIR absorbance and more effective photothermal efficiency.

Gold nanoparticle based dot-blot immunoassay for sensitively detecting Alzheimer's disease related ß-amyloid peptide.

A simple, sensitive gold nanoparticle (GNP)-based dot-blot immunoassay has been developed for detecting Alzheimer's disease related ß-amyloid peptide 1-42 (Aß(1-42)) down to a 50 pg mL(-1) level in aqueous solution. Practical samples (cerebrospinal fluid (CSF), cell culturing mediums and cell lysates) have been used to demonstrate the ability of the assay.

Microarray-based technology for glycomics analysis.

In the post-genomic era, glycomics (the functional study of carbohydrates in living organisms) has come into the forefront of biological research because the interactions of glycoconjugates with proteins not only occur widely in biological processes of cells but also initiate infection of host cells by bacteria and viruses. Microarrays have been reportedly successful in carbohydrate-protein interaction as well as cellular surface glycan profiling. This review provides an overview of recent progress in the development of microarray-based techniques for glycomic studies. The fabrication, application and challenge/bottleneck of glycan/lectin microarrays have been summarized and discussed.

Phenylboronic acid functionalized gold nanoparticles for highly sensitive detection of Staphylococcus aureus.

Herein, we report a phenylboronic acid functionalized gold nanoparticle (GNP)-based colorimetric assay for rapid detection of Staphylococcus aureus (S. aureus) with high sensitivity. In this approach, GNPs can bind to S. aureus by the reaction of phenylboronic acid with the cis-diol configuration in glycans on the bacterial surface, providing a colorimetric readout of the binding event. Using this strategy, we have been able to quantify S. aureus at a concentration of 50 cells per mL (three times the standard deviation divided by the slope of the working curve) in aqueous solution.

Studying the interaction of carbohydrate-protein on the dendrimer-modified solid support by microarray-based plasmon resonance light scattering assay.

Here, a three-dimensional (3D) carbohydrate microarray-based plasmon resonance light scattering (RLS) assay has been established for studying carbohydrate-lectin binding with high selectivity. The 3D carbohydrate microarray is fabricated by immobilizing amino-modified carbohydrates on the home-made fourth-generation (G4) NH(2)-terminated poly(amidoamine) dendrimers (PAMAM)-modified substrate. After marking the carbohydrate-lectin binding events by 13 nm peptide-stabilized gold nanoparticles through the biotin-avidin reaction, the 3D microarray can be directly detected by the RLS scanner without the conventional silver enhancement step. The well defined recognition systems: three monosaccharides (Man-α, Glc-α and Gal-ß) with two lectins (Con A and RCA 120), have been chosen here to establish the RLS assay, respectively. Quantitative determination of the surface dissociation constants (K(D,surf)) for surface carbohydrates and lectins has been achieved. In addition, inhibition values (i.e. the inhibition constants (K(i)) and the concentrations of inhibitors required to produce 50% inhibition (IC(50))) for inhibitors in solution are also demonstrated by the saccharide competing assays.