CircUBE2I regulates YAP/TAZ signaling pathway through miR-659-3p/PSMA1 axis to promote human lung adenocarcinoma cell progression.

Circular RNAs (circRNAs) exhibit wide expression across human tissues and play pivotal roles in tumorigenesis and cancer progression. However, studies regarding the function and mechanism of circRNAs in lung adenocarcinoma (LUAD) are insufficient, it needs to be further explored. This investigation aimes to describe dysregulated circRNAs in LUAD, elucidate their functional roles in tumor progression, and establish novel molecular targets for diagnostic and therapeutic applications in pulmonary malignancies. Functional studies were performed to clarify the regulatory effects of circUBE2I on LUAD progression in vitro and in vivo. To elucidate the molecular mechanisms of circUBE2I, we performed dual-luciferase reporter assays, fluorescence in situ hybridization (FISH), RNA immunoprecipitation (RIP), and Chromatin Isolation by RNA Purification (ChIRP). CircUBE2I expression was up-regulated in LUAD tissues, plasma, and cell lines. CircUBE2I is crucial in the proliferation, migration, and regulation of the cell cycle in lung cancer cells in vitro. Subsequent mechanistic investigations showed that circUBE2I functions as a competitive endogenous RNA (ceRNA). It can effectively sequester miR-659-3p, thus reducing its inhibitory effect on PSMA1 expression. This molecular interaction ultimately activates the yes-associated protein/transcriptional coactivator with PDZ-binding motif (YAP/TAZ) pathway. In conclusion, our findings demonstrate that circUBE2I is a novel circRNA that promotes LUAD cells proliferation and migration by modulating the YAP/TAZ signaling pathway through the miR-659-3p/PSMA1 axis, suggesting its potential as both a diagnostic biomarker and therapeutic target for LUAD.