CircACTR2 Promotes Bladder Cancer Progression Through IKBKB-mediated NF-κB Signaling Pathway Activation

Background Circular RNAs (circRNAs) have significant roles in tumor progression. The role of circRNA derived from ARP2 actin-related protein 2 homolog (circACTR2) has been reported in various human diseases. However, the functions and regulatory mechanisms of circACTR2 in Bladder Cancer (BCa) remain unknown. Objectives: This study aims to explore the biological role and regulatory mechanism of circACTR2 in BCa. Methods We analyzed the effects of circACTR2 on BCa through bioinformatics analyses, RT-qPCR, and cell function assays. Results We observed the upregulation of circACTR2 in BCa tissues and validated its circular structure. Loss-of-function assays demonstrated that silencing circACTR2 suppressed the proliferation, invasion, and migration of BCa cells. Mechanistic investigation revealed that circACTR2 sponges miR-219a-2-3p to elevate the expression of the inhibitor of nuclear factor kappa B kinase subunit beta (IKBKB). This induced upregulation of IKKβ protein promoted the nuclear translocation of p65, thereby activating the NF-κB signaling pathway Conclusions Our findings indicate that circACTR2 promotes BCa cell proliferation, migration, and invasion by activating the NF-κB signaling pathway via the miR-219a-2-3p/IKBKB axis, potentially unveiling a new therapeutic target for BCa.