• DANCR is significantly upregulated in breast cancer brain metastases (BCBM) and correlates with poor prognosis, serving as a potential prognostic biomarker.
• DANCR promotes breast cancer cell proliferation, migration, and invasion both in vitro and in vivo, with PTGS2 identified as a key downstream effector.
• Mechanistically, DANCR acts as a competing endogenous RNA (ceRNA) by sponging miR-758-3p, thereby relieving miR-758-3p-mediated suppression of PTGS2 and DANCR itself.
• The DANCR/miR-758-3p/PTGS2 axis offers a promising therapeutic target for BCBM, with potential for developing novel treatment strategies.