Circ_0074027 Contributes to Non-Small Cell Lung Cancer Progression by Upregulating Expression Through miR-335-5p.

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. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to determine the expression of circ_0074027, paired like homeodomain 1 () mRNA, microRNA-335-5p (miR-335-5p), and cullin 4B () 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 . The murine xenograft model was established to investigate the role of circ_0074027 . 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 and inhibited tumor growth . 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, was a target gene of miR-335-5p. 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. Circ_0074027 facilitated NSCLC cell progression through regulating miR-335-5p/ axis.