CALD1-derived circ-0003746 targeting miR-526b promotes EMT-mediated bladder cancer progression.

CALD1 is critical to bladder cancer (BCa) development. Circ-0003746 is a circRNA derived from two exons of CALD1. However, the functional role of circ-0003746 in BCa remains inadequately explored. This study investigated its involvement in BCa. Circ-0003746 was found to be overexpressed in BCa tissues and cell lines. Silencing circ-0003746 suppressed both proliferation and migration of BCa cells in vitro and in vivo. miR-526b was identified as a potential target of circ-0003746. Luciferase reporter assays confirmed the interaction between circ-0003746 and miR-526b. Mechanistically, circ-0003746 promotes epithelial-mesenchymal transition (EMT) by sequestering miR-526b, thereby advancing BCa progression. These findings highlight the role of circ-0003746 in regulating the miR-526b/EMT axis, positioning it as a potential biomarker for BCa.