RESUMO
We have reported that the Ag nanostructure-based substrate is particularly suitable for surface-enhanced Raman scattering when it is coated with monolayer graphene, an optically transparent and chemistry-inertness material in the visible range. Ag bowtie nanoantenna arrays and Ag nanogrids were fabricated using plasma-assisted nanosphere lithography. Our measurements show that atmospheric sulfur containing compounds are powerless to break in the monolayer graphene to vulcanize the surfaces of the Ag bowtie nanoantenna arrays and Ag nanogrids by various means, including scanning electron microscopy (SEM) and x-ray photoelectron spectroscopy (XPS). Furthermore, the Ag nanostructure substrate coated with the monolayer graphene film shows a larger enhancement of Raman activity and the electromagnetic field than the uncoated substrate. Compared with those of bare Ag nanostructures, the averaged EFs of graphene-film-coated Ag nanostructures were estimated to be about 21 and 5 for Ag bowtie nanoantenna arrays and nanogrids after one month later in air, respectively. These observations are further supported by theoretical calculations.
RESUMO
Background: Circular RNAs (circRNAs) are crucial regulators in human cancers, including non-small cell lung cancer (NSCLC). In this study, we explore the biological functions and molecular mechanisms of circ_0074027 in NSCLC. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to determine the expression of circ_0074027, paired like homeodomain 1 (PITX1) mRNA, microRNA-335-5p (miR-335-5p), and cullin 4B (CUL4B) mRNA. The features of circ_0074027 were analyzed by RNase R digestion assay. Flow cytometry analysis was adopted to analyze cell cycle and cell apoptosis. Cell counting kit-8 (CCK-8) assay and colony formation assay were performed to assess cell proliferation. Western blot assay was conducted to measure protein levels. Dual-luciferase reporter and RNA pull-down assays were carried out to verify the relationships among circ_0074027, miR-335-5p, and CUL4B. The murine xenograft model was established to investigate the role of circ_0074027 in vivo. Results: High expression of circ_0074027 was found in NSCLC tissues and cells. Circ_0074027 knockdown suppressed cell viability, cell cycle process, and colony formation and promoted apoptosis in NSCLC cells in vitro and inhibited tumor growth in vivo. Circ_0074027 acted as a sponge of miR-335-5p. The effect of circ_0074027 knockdown on NSCLC progression was weakened by miR-335-5p inhibition. Moreover, CUL4B was a target gene of miR-335-5p. CUL4B overexpression reversed the inhibitory effects on cell viability, cell cycle process, and colony formation and the promotional effect on cell apoptosis caused by miR-335-5p in NSCLC. Conclusion: Circ_0074027 facilitated NSCLC cell progression through regulating miR-335-5p/CUL4B axis.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/genética , Proteínas Culina/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genéticaRESUMO
Background: Lung cancer (LC) represents a leading cause of cancer-related deaths. The aim of this study was to analyze the application value of ZIC5 in the prognosis evaluation of LC. Materials and Methods: The mRNA and protein levels of ZIC5 in LC tissues and adjacent normal controls were detected by quantitative real-time polymerase chain reaction and Western blot analysis, respectively. Chi-square test was performed to estimate the association between ZIC5 expression and clinical features. Furthermore, overall survival (OS) curves were plotted using Kaplan-Meier method with log rank test. The prognosis analysis was analyzed using Cox proportional hazards model. Results: Compared with that of noncancerous tissues, the expression of ZIC5 in LC tissues was significantly increased at both protein and mRNA levels (p < 0.001). Moreover, ZIC5 expression showed a positive correlation with differentiation (p = 0.001) and tumor size (p = 0.016). Survival analysis suggested that high expression of ZIC5 predicted shorter OS (log rank test, p = 0.007). ZIC5 might be an independent prognostic biomarker for LC (hazard ratio = 2.892; 95% confidence interval, 1.297-6.449; p = 0.009). Conclusions: ZIC5 expression is upregulated in LC, and it may be employed as a prognostic biomarker for patients with LC.