In bladder cancer, circular RNA circXRN2 interacts with speckle-type POZ (SPOP) to activate the Hippo signaling pathway, inhibiting H3K18la of the lipocalin-2 (LCN2) gene promoter region, thereby downregulating LCN2 expression and suppressing tumor progression (90). The gene discussed is LCN2; the disease is urinary bladder cancer.