ENAH-202 promotes cancer progression in oral squamous cell carcinoma by regulating ZNF502/VIM axis.

BACKGROUND: We aimed to demonstrate the regulatory effect of long non-coding RNA (lncRNA) ENAH-202 on oral squamous cell carcinoma (OSCC) development as well as its molecular mechanism. METHODS: We detected ENAH-202 expression in OSCC tissues and cell lines by quantitative real-time PCR (qPCR). The biological function of ENAH-202 was assessed in vitro and in vivo using CCK-8, colony formation assays, transwell assays, xenograft formation, and tail vein injection. The further molecular mechanism by which ENAH-202 promoted OSCC progression was identified using RNA pull-down, LS-MS/MS analysis, RNA immunoprecipitation (RIP), and chromatin immunoprecipitation (ChIP) assays. RESULTS: ENAH-202 was significantly upregulated in OSCC tissues and cells. ENAH-202 promoted OSCC cell proliferation, migration, and invasion in vitro and in vivo. The expression of enabled homolog (ENAH) and epithelial-to-mesenchymal transition (EMT)-related proteins was changed with the expression of ENAH-202. Moreover, ENAH-202 promoted the transcription of Vimentin (VIM) by binding with ZNF502, which can help ENAH-202 promote OSCC progression. CONCLUSIONS: ENAH-202 facilitated OSCC cell proliferation and metastasis by regulating ZNF502/VIM axis, which played an important role in OSCC progression.

Comprehensive analysis of circRNAs for N7-methylguanosine methylation modification in human oral squamous cell carcinoma.

N7-methylguanosine (m7G) modification is closely related to the occurrence of tumors. However, the m7G modification of circRNAs in oral squamous cell carcinoma (OSCC) remains to be investigated. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) was used to measure the methylation levels of m7G and identify m7G sites in circRNAs in human OSCC and normal tissues. The host genes of differentially methylated and differentially expressed circRNAs were analyzed by Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, and circRNA-miRNA-mRNA networks were predicted using the miRanda and miRDB databases. The analysis identified 2348 m7G peaks in 624 circRNAs in OSCC tissues. In addition, the source of m7G-methylated circRNAs in OSCC was mainly the sense overlap region compared with normal tissues. The most conserved m7G motif in OSCC tissues was CCUGU, whereas the most conserved motif in normal tissues was RCCUG (R = G/A). Importantly, GO enrichment and KEGG pathway analysis showed that the host genes of differentially methylated and differentially expressed circRNAs were involved in many cellular biological functions. Furthermore, the significantly differentially expressed circRNAs were analyzed to predict the circRNA-miRNA-mRNA networks. This study revealed the whole profile of circRNAs of differential m7G methylation in OSCC and suggests that m7G-modified circRNAs may impact the development of OSCC.

Flow-through electrochemical organophosphorus degradation and phosphorus recovery: The essential role of chlorine radical.

Phosphorus scarcity and the deleterious ecological impact of the release of organophosphorus pesticides have emerged as critical global issues. Previous research has shown the ability of electrochemistry to induce the precipitation of calcium phosphate from phosphorus-laden wastewater to recover the phosphorus. The current study presents a flow-through electrochemical system consisting of a column-shaped electrochemical reactor, a tubular stainless-steel (SS) cathode, and a titanium suboxides (TiSO) anode. This system simultaneously oxidizes tetrakis (hydroxymethyl) phosphonium sulfate (THPS) and recycles phosphates. The influence of current density, flow rate, and initial calcium ions concentration were examined under continuous flow operation. To enhance the electrochemical reactor's performance, we elevated the current density from 5 to 30 mA cm-2, which caused the phosphorus recovery efficiency to increase from 37% to 72% within 120 min, accompanied by an enhancement of the THPS mineralization efficiency from 57% to 90%. These improvements were likely due to the higher yield of reactive species chloride species (Cl•) formed at the TiSO anode and the higher local pH at the cathode. By investigating the formation of Cl• at the TiSO anode, we found that THPS mineralization exceeded 75% in the presence of NaCl at a current density of 20 mA cm-2. The demonstrated performance of the flow-through electrochemical system should enable the utilization of anodic oxidation-cathodic precipitation for the recovery of phosphorus from organophosphorus-contaminated wastewater.

Mutant p53 in head and neck squamous cell carcinoma: Molecular mechanism of gain­of­function and targeting therapy (Review).

Head and neck squamous cell carcinoma (HNSCC) is one of the most widespread malignancies worldwide. p53, as a transcription factor, can play its role in tumor suppression by activating the expression of numerous target genes. However, p53 is one of the most commonly mutated genes, which frequently harbors missense mutations. These missense mutations are nucleotide substitutions that result in the substitution of an amino acid in the DNA binding domain. Most p53 mutations in HNSCC are missense mutations and the mutation rate of p53 reaches 65­85%. p53 mutation not only inhibits the tumor suppressive function of p53 but also provides novel functions to facilitate tumor recurrence, called gain­of­function (GOF). The present study focused on the prevalence and clinical relevance of p53 mutations in HNSCC, and further described how mutant p53 accumulates. Moreover, mutant p53 in HNSCC can interact with proteins, RNA, and exosomes to exert effects on proliferation, migration, invasion, immunosuppression, and metabolism. Finally, several treatment strategies have been proposed to abolish the tumor­promoting function of mutant p53; these strategies include reactivation of mutant p53 into wild­type p53, induction of mutant p53 degradation, enhancement of the synthetic lethality of mutant p53, and treatment with immunotherapy. Due to the high frequency of p53 mutations in HNSCC, a further understanding of the mechanism of mutant p53 may provide potential applications for targeted therapy in patients with HNSCC.

Copper Nanowire Networks: An Effective Electrochemical Peroxymonosulfate Activator toward Nitrogenous Pollutant Abatement.

Herein, we developed an electrochemical filtration system for effective and selective abatement of nitrogenous organic pollutants via peroxymonosulfate (PMS) activation. Highly conductive and porous copper nanowire (CuNW) networks were constructed to serve simultaneously as catalyst, electrode, and filtration media. In one demonstration of the CuNW network's capability, a single pass through a CuNW filter (τ < 2 s) degraded 94.8% of sulfamethoxazole (SMX) at an applied potential of -0.4 V vs SHE. The exposed {111} crystal plane of CuNW triggered atomic hydrogen (H*) generation on sites, which contributed to effective PMS reduction. Meanwhile, with the involvement of SMX, a Cu-N bond was formed by the interactions between the -NH2 group of SMX and the Cu sites of CuNW, accompanied by the redox cycling of Cu2+/Cu+, which was facilitated by the applied potential. The different charges of the active Cu sites made it easier to withdraw electrons and promote PMS oxidation. Theoretical calculations and experimental results were combined to suggest a mechanism for pollution abatement with CuNW networks. The results showed that system efficacy for the degradation of a wide array of nitrogenous pollutants was robust across a broad range of solution pH and complex aqueous matrices. The flow-through operation of the CuNW filter outperformed conventional batch electrochemistry due to convection-enhanced mass transport. This study provides a new strategy for environmental remediation by integrating state-of-the-art material science, advanced oxidation processes, and microfiltration technology.

Atomic H*-mediated electrochemical removal of low concentration antimonite and recovery of antimony from water.

Compounds containing antimony (Sb) are broadly used as starting materials for a wide range of industrial products, leading to serious water pollution associated with Sb rock mining as well as Sb leaching. Herein, we proposed an innovative design of an electrified membrane consisted of bimetallic palladium and iron nanoparticles (Pd-Fe NPs) supported on conductive carbon nanotube (CNT) networks. The nanohybrid filter enabled effective generation and retainment of atomic hydrogen (H*) under an electric field, which further contributed to the complete electroreduction of antimonite (Sb(III)). The highest atomic H* yield and Sb(III) removal kinetics were identified once a potential of -1.0 V vs. Ag/AgCl was exerted. Compared to the pristine CNT, Pd-CNT and Fe-CNT filters, the reaction rate constant of the Pd/Fe-CNT filter was increased 5.15-, 2.39-, and 1.76-fold, respectively for electrochemical removal of Sb(III). The results denoted that the superior performance of the Pd/Fe-CNT nanohybrid filter originated from: (1) the flow-through design, which enhanced mass transport, (2) the bimetallic design, which increased the catalytic activity, and (3) the collective contribution from atomic H*-mediated indirect reduction and direct electron transfer reduction mechanisms. The robust system performance occurred over a broad range of pH values, a variety of water matrices and can withstand several cycles of experiments. Our findings highlight an effective electro-filtration strategy to induce atomic H*-mediated electrochemical removal and recovery of Sb from water.

Transcriptome Mapping of the Internal N7-Methylguanosine Methylome in Messenger RNAs in Human Oral Squamous Cell Carcinoma.

BACKGROUND: Internal N7-methylguanosine (m7G) methylation in mammalian messenger RNAs (mRNAs) is essential in disease development. However, the status of internally m7G-modified mRNAs in oral squamous cell carcinoma (OSCC) remains poorly understood. METHODS: Methylated RNA immunoprecipitation sequencing (MeRIP-seq) was used to identify the m7G modification level of mRNAs and the expression of mRNAs between OSCC and normal tissues. These differentially methylated and expressed genes were subjected to Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and construction of protein-protein interaction (PPI) networks. Quantitative real-time PCR (qPCR) assay was performed to detect the expression of Baculoviral IAP Repeat Containing 3 (BIRC3) in vitro. The biological function of BIRC3 in OSCC was clarified using CCK-8, Transwell migration and Western blot assays. RESULTS: The m7G-mRNA profile showed 9514 unique m7G peaks within 7455 genes in OSCC tissues. In addition, the most conserved m7G motif within mRNAs in OSCC was GGARG (R = G/A). The identified m7G peaks were mainly distributed in the coding sequence region within mRNAs in OSCC. GO enrichment and KEGG pathway analyses showed that m7G-modified genes were closely related to cancer progression. m7G-modified hub genes were screened from the constructed PPI networks. Furthermore, BIRC3 with high m7G methylation showed high expression in OSCC cell lines, as confirmed by qPCR assay. Functionally, the knockdown of BIRC3 significantly inhibited the proliferation and migration ability of CAL-27 cells in vitro functional assays. In addition, the relative expression of E-cadherin expression was elevated, while Vimentin and N-cadherin protein expression was decreased in CAL-27 cells transfected with si-BIRC3. This study suggests that BIRC3 could promote OSCC proliferation and migration, which may be associated with involvement in epithelial-mesenchymal transition (EMT) progression. CONCLUSIONS: This paper constructed a transcriptome map of internal m7G in mRNAs, which provides potential research value to study the role of m7G methylation in OSCC.

Atomic Hydrogen in Electrocatalytic Systems: Generation, Identification, and Environmental Applications.

Electrochemical reduction has emerged as a viable technology for the removal of a variety of organic contaminants from water. Atomic hydrogen (H*) is the primary species generated in electrochemical reduction processes. In this work, identification and quantification for H* are reviewed with a focus on methods used to generate H* at different positions. Additionally, we present recently developed proposals for the surface chemistry mechanisms of H* on the most commonly used cathodes as well as the use of H* in standard electrochemical reactors. The proposed reaction pathways in different H* systems for environmental applications are also discussed in detail. As shown in this review, the key hurdles facing H* reduction technologies are related to i) the establishment of systematic and practical synthetic methods; ii) the development of effective identification approaches with high specificity; and, iii) an in-depth exploration of the H* reaction mechanism to better understand the reaction process of H*.

Electrified nanohybrid filter for enhanced phosphorus removal from water.

Phosphorus (P) has been identified as a major cause of eutrophication. One feasible way to deal with P-containing wastewater is to employ advanced adsorbents with high P affinity. Towards this end, the loading of these sorbents onto a conductive scaffold would facilitate the introduction of an electric field into the reaction system thereby permitting a continuous-flow operation and improved P sorption kinetics. Here, the preparation and evaluation of an electroactive carbon nanotube (CNT) filter functionalized with cerium-based metal organic frameworks (Ce-MOF) is reported. Various advanced characterization techniques confirmed the successful fabrication of the Ce-MOF/CNT nanohybrid filter. The results suggested that the nanohybrid filter had a maximum P adsorption capacity of 22.41 mg g-1, which compared favorably with other state-of-the-art P sorbents. Ce-MOF loading, applied voltage and flow rate each increased the rate constants for phosphate removal by factors of 1.6, 2.1 and 5.8 times relative to the absent states. The underlying P sorption mechanisms involved outer-sphere surface complexation (electrostatic attraction), inner-sphere surface complexation (Ce-O-P) and diffusion. The performance was tolerant of a wide operational pH range and different water matrices. The Ce-MOF/CNT electrochemical filter described in this study provides a viable strategy to address the challenging issues associated with aqueous P pollution.

Nanoscale electric-field imaging based on a quantum sensor and its charge-state control under ambient condition.

Nitrogen-vacancy (NV) centers in diamond can be used as quantum sensors to image the magnetic field with nanoscale resolution. However, nanoscale electric-field mapping has not been achieved so far because of the relatively weak coupling strength between NV and electric field. Here, using individual shallow NVs, we quantitatively image electric field contours from a sharp tip of a qPlus-based atomic force microscope (AFM), and achieve a spatial resolution of ~10 nm. Through such local electric fields, we demonstrated electric control of NV's charge state with sub-5 nm precision. This work represents the first step towards nanoscale scanning electrometry based on a single quantum sensor and may open up the possibility of quantitatively mapping local charge, electric polarization, and dielectric response in a broad spectrum of functional materials at nanoscale.

A novel electrocatalytic filtration system with carbon nanotube supported nanoscale zerovalent copper toward ultrafast oxidation of organic pollutants.

In this study, we designed an integrated electrochemical filtration system for catalytic activation of peroxymonosulfate (PMS) and degradation of aqueous microcontaminants. Composites of carbon nanotube (CNT) and nanoscale zero valence copper (nZVC) were developed to serve as high-performance catalysts, electrode and filtration media simultaneously. We observed both radical and nonradical reaction pathways, which collectively contributed to the degradation of model pollutants. Congo red was completely removed via a single-pass through the nZVCCNT filter (τ <2 s) at neutral pH. The rapid kinetics of Congo red degradation were maintained across a wide pH range (from 3.0-7.0), in complicated matrixes (e.g., tap water and lake water), and for the degradation of a wide array of persistent organic contaminants. The superior activity of nZVCCNT stems from the boosted redox cycles of Cu2+/Cu+ in the presence of an external electric field. The flow-through design remarkably outperformed the conventional batch system due to the convection-enhanced mass transport. Mechanism studies suggested that the carbonyl group and electrophilic oxygen of CNT served as electron donor and electron acceptor, respectively, to activate PMS to generate •OH and 1O2via one-electron transport. The electron-deficient Cu atoms are prone to react with PMS via surface hydroxyl group to produce reactive intermediates (Cu2+-O-O-SO3-), and then 1O2 will be generated by breaking the coordination bond of the metastable intermediate. The study will provide a green strategy for the remediation of organic pollution by a highly efficient and integrated system based on catalytic oxidation, electrochemistry, and nano-filtration techniques.