Identification of crucial microRNAs and genes in hypoxia-induced human lung adenocarcinoma cells

BACKGROUND: Variations of microRNA (miRNA) expression profile in hypoxic lung cancer cells have not been studied so far. Therefore, using miRNA microarray technology, this study aimed to study the miRNA expression profile and investigate the potential crucial miRNAs and their target genes in hypoxia-induced human lung adenocarcinoma cells. MATERIALS AND METHODS: Based on miRNA microarray, miRNA expression profiling of hypoxia-induced lung adenocarcinoma A549 cells was obtained. After identification of differentially expressed miRNAs (DE-miRNAs) in hypoxic cells, target genes of DE-miRNAs were predicted, and functional enrichment analysis of targets was conducted. Furthermore, the expression levels of DE-miRNAs and their target genes were validated by real-time quantitative polymerase chain reaction. In addition, using miRNA mimics, the effect of overexpressed DE-miRNAs on A549 cell behaviors (cell proliferation, cell cycle, and apoptosis) was evaluated. RESULTS: In total, 14 DE-miRNAs (nine upregulated miRNAs and five downregulated miRNAs) were identified in hypoxic cells, compared with normoxic cells. Target genes of both upregulated and downregulated miRNAs were enriched in the functions such as chromatin modification, and pathways such as Wnt signaling pathway and transforming growth factor (TGF)-β signaling pathway. The expression levels of several miRNAs and their target genes were confirmed, including hsa-miR-301b/FOXF2, hsa-miR-148b-3p/WNT10B, hsa-miR-769-5p/(SMAD2, ARID1A), and hsa-miR-622. Among them, hsa-miR-301b was verified to regulate FOXF2, and hsa-miR-769-5p was verified to modulate ARID1A. In addition, the overexpression of hsa-miR-301b and hsa-miR-769-5p significantly affected the cell cycle of A549 cells, but not cell proliferation and apoptosis. CONCLUSION: miRNA expression profile was changed in hypoxia-induced lung cancer cells. Those validated miRNAs and genes may play crucial roles in the response of lung cancer cells to hypoxia

Ultrahigh strength, modulus, and conductivity of graphitic fibers by macromolecular coalescence

Theoretical considerations suggest that the strength of carbon nanotube (CNT) fibers be exceptional; however, their mechanical performance values are much lower than the theoretical values. To achieve macroscopic fibers with ultrahigh performance, we developed a method to form multidimensional nanostructures by coalescence of individual nanotubes. The highly aligned wet-spun fibers of single- or double-walled nanotube bundles were graphitized to induce nanotube collapse and multi-inner walled structures. These advanced nanostructures formed a network of interconnected, close-packed graphitic domains. Their near-perfect alignment and high longitudinal crystallinity that increased the shear strength between CNTs while retaining notable flexibility. The resulting fibers have an exceptional combination of high tensile strength (6.57 GPa), modulus (629 GPa), thermal conductivity (482 W/m·K), and electrical conductivity (2.2 MS/m), thereby overcoming the limits associated with conventional synthetic fibers

Construction of asthma related competing endogenous RNA network revealed novel long non-coding RNAs and potential new drugs

Abstract Background Asthma is a heterogeneous disease characterized by chronic airway inflammation. Long non-coding RNA can act as competing endogenous RNA to mRNA, and play significant role in many diseases. However, there is little known about the profiles of long non-coding RNA and the long non-coding RNA related competing endogenous RNA network in asthma. In current study, we aimed to explore the long non-coding RNA-microRNA-mRNA competing endogenous RNA network in asthma and their potential implications for therapy and prognosis. Methods Asthma-related gene expression profiles were downloaded from the Gene Expression Omnibus database, re-annotated with these genes and identified for asthma-associated differentially expressed mRNAs and long non-coding RNAs. The long non-coding RNA-miRNA interaction data and mRNA-miRNA interaction data were downloaded using the starBase database to construct a long non-coding RNA-miRNA-mRNA global competing endogenous RNA network and extract asthma-related differentially expressed competing endogenous RNA network. Finally, functional enrichment analysis and drug repositioning of asthma-associated differentially expressed competing endogenous RNA networks were performed to further identify key long non-coding RNAs and potential therapeutics associated with asthma. Results This study constructed an asthma-associated competing endogenous RNA network, determined 5 key long non-coding RNAs (MALAT1, MIR17HG, CASC2, MAGI2-AS3, DAPK1-IT1) and identified 8 potential new drugs (Tamoxifen, Ruxolitinib, Tretinoin, Quercetin, Dasatinib, Levocarnitine, Niflumic Acid, Glyburide). Conclusions The results suggested that long non-coding RNA played an important role in asthma, and these novel long non-coding RNAs could be potential therapeutic target and prognostic biomarkers. At the same time, potential new drugs for asthma treatment have been discovered through drug repositioning techniques, providing a new direction for the treatment of asthma. </jats:sec

Circular RNA hsa_circ_0014130 Inhibits Apoptosis in Non–Small Cell Lung Cancer by Sponging miR-136-5p and Upregulating BCL2

Abstract Previous studies indicated that circular RNAs (circRNA) played vital roles in the development of non–small cell lung cancer (NSCLC). Although hsa_circ_0014130 might be a potential NSCLC biomarker, its function in NSCLC remains unknown. Thus, this study aimed to investigate the role of hsa_circ_0014130 in the progression of NSCLC. The levels of hsa_circ_0014130 in NSCLC tissues and adjacent normal tissues were determined by qRT-PCR. In addition, the expressions of Bcl-2 and cleaved caspase-3 in A549 cells were detected with Western blot analysis. Meanwhile, the dual luciferase reporter system assay was used to determine the interaction of hsa_circ_0014130 and miR-136-5p or Bcl-2 and miR-136-5p in NSCLC, respectively. The level of hsa_circ_0014130 was significantly upregulated in NSCLC tissues. Downregulation of hsa_circ_0014130 markedly inhibited the proliferation and invasion of A549 cells via inducing apoptosis. In addition, downregulation of hsa_circ_0014130 inhibited the tumorigenesis of subcutaneous A549 xenograft in mice in vivo. Meanwhile, mechanistic analysis indicated that downregulation of hsa_circ_0014130 decreased the expression of miR-136-5p–targeted gene Bcl-2 via acting as a competitive “sponge” of miR-136-5p. In this study, we found that hsa_circ_0014130 was upregulated in NSCLC tissues. In addition, hsa_circ_0014130 functions as a tumor promoter in NSCLC to promote tumor growth through upregulating Bcl-2 partially via “sponging” miR-136-5p. Implications: In conclusion, hsa_circ_0014130 might function as a prognostic factor for patients with NSCLC and might be a therapeutic target for the treatment of NSCLC in future. </jats:sec

Combustion Melting Characterisation of Solid Fuel Obtained from Sewage Sludge

Solid fuelization technology can increase the heating value of sewage sludge such that it can be utilised as a fossil fuel substitutes. Reducing landfilling of bottom and fly ash resulting from heavy metals contained in sewage sludge is challenging. Hence, combustion melting technology (CMT), which can discharge bottom ash in the form of slag, has been proposed herein as an alternative to the conventional incineration technology. However, further research is required to improve the flowability of slag. Applicability of CMT for the stable treatment of heavy metals in the ash generated during the energisation of sewage sludge solid fuel has been reviewed. The change in the degree of fluidity was identified via a laboratory-scale fluidity measurement experiment following changes in melting temperature, mixing ratio of sewage sludge and sawdust, and basicity. The pouring index (PI) of sewage sludge solid fuel (pellet) was maintained at a level of about 60% at a basicity index of 0.8. Based on the results, the slagging rates and volume reduction rates, exhaust gas analysis, and heavy metal elution characteristics under oxygen enrichment were derived from a 2 ton/day combustion melting pilot plant experiment; thereafter, the feasibility of combustion melting of sewage sludge solid fuel was determined