CircFOXK2 induces non-small cell lung cancer tumorigenesis through the miR-328-5p/PKP3 axis

Circular RNAs (circRNAs) are non-coding RNAs (ncRNAs) implicated in the onset and advancement of various human cancers. Among these, circFOXK2 has been linked to non-small cell lung cancer (NSCLC); however, its precise functions and underlying molecular mechanisms are not fully understood. This study shows the first experimental findings that circFOXK2 promotes NSCLC tumor progression by modulating the miR-328-5p/PKP3 signaling pathway. Levels of circFOXK2, miR-328-5p, and PKP3 were evaluated by qRT-PCR. Cellular (NSCLSC) proliferation was examined via CCK-8 assays, migratory capacity via wound healing, and invasive potential via Transwell assays. Potential binding interactions between miR-328-5p and circFOXK2 were first assessed using bioinformatic analysis and verified using a dual-luciferase reporter assay (DLRGAs). Regulatory relationships among circFOXK2, miR-328-5p, and PKP3 were further investigated through qRT-PCR analysis. Elevated expression of circFOXK2 and reduced levels of miR-328-5p were observed in NSCLC cell lines and tissues. Functionally, circFOXK2 enhanced cellular propagation, dissemination, and invasion in vitro. Mechanistic evaluation revealed that circFOXK2 upregulates PKP3 by acting as an miR-328-5p sponge. The findings demonstrate that circFOXK2 contributes to NSCLC tumorigenesis via modulation of the miR-328-5p/PKP3 pathway, identifying this signaling axis as a potential therapeutic target in NSCLC.