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Background: Circular RNAs (circRNAs) act as vital regulators of gene expression in a variety of cancers. However, the role of circRNAs in gastric cancer (GC) remains largely unexplored. Herein, we identified that circTMEM87A sponges miR-142-5p to promote GC progression through up-regulating ULK1 expression.Methods: The expression of circTMEM87A in GC was determined by RNA sequencing and quantitative real-time PCR (qRT-PCR). The effects of knockdown or exogenous expression of circTMEM87A on GC cell phenotypes were evaluated both in vitro and in vivo. The interacting miRNA of circTMEM87A was predicted by bioinformatics and confirmed by RNA pull-down, dual-luciferase reporter assay and fluorescence in situ hybridization (FISH). The mechanism by which circTMEM87A/miR-142-5p/ULK1 axis promotes GC was determined by western blot, GFP/mRFP-LC3 puncta analysis, transmission electron microscope (TEM).Results: CircTMEM87A was dramatically elevated in GC tissues and cell lines, and high circTMEM87A expression was closely correlated with poor prognosis of GC patients. Knockdown of circTMEM87A suppressed cell growth, migration, invasion and induced apoptosis in vitro, as well as inhibited GC tumorigenicity and lung metastasis potential in vivo. Meanwhile, circTMEM87A overexpression had the opposite effects. Furthermore, we demonstrated that circTMEM87A could act as a sponge of miR-142-5p to regulate ULK1 expression and GC progression.Conclusions: Our findings suggest that circTMEM87A functions as an oncogene through the miR-142-5p/ULK1 axis in GC. CircTMEM87A might be a prognostic biomarker as well as a promising therapeutic target for GC. [ABSTRACT FROM AUTHOR]

(1 − x)BaTiO xBi(ZnNb)O [(1 − x)BT- xBZN, 0 ≤ x ≤ 0.2] ceramics were prepared via a conventional solid-state reaction method. X-ray diffraction (XRD) patterns and Raman spectra analysis show that the ceramics are tetragonal phase when x ≤ 0.02, and transform to pseudocubic phase as x ≥ 0.06. The temperature and frequency dependences of relative permittivity indicate a gradual crossover from a classic ferroelectric to relaxor ferroelectric. The dielectric relaxor behavior follows a modified Curie-Weiss law. The degree of the phase transition diffuseness ( γ) and the deviation from the Curie-Weiss law $$ (\Delta T_{\rm{d}} ) $$ increase to the maximum at x = 0.08, and subsequently decrease with further increasing x values, which associated with the appearance of polar nanoregions on account of the formation of random fields included local electric fields and elastic fields. Nevertheless, the random fields may decrease by reason of the interaction between the local electric fields and elastic fields. [ABSTRACT FROM AUTHOR]