AR-induced Long Non-coding RNA LINC01503 Facilitates Proliferation and Metastasis Via the SFPQ-FOSL1 Axis in Nasopharyngeal Carcinoma

Increasing evidence indicates that long non-coding RNAs (lncRNAs) play vital roles in the tumorigenesis and progression of cancers. However, the functions and regulatory mechanisms of lncRNAs in nasopharyngeal carcinoma (NPC) are still largely unknown. Our previous lncRNA expression profiles identified that LINC01503 was overexpressed in NPC. Here, we verified that LINC01503 was highly expressed in NPC and correlated with poor prognosis. LINC01503 promoted NPC cell proliferation, migration, and invasion in vitro, and facilitated tumor growth and metastasis in vivo. Mechanistically, LINC01503 recruited splicing factor proline-and glutamine-rich (SFPQ) to activate Fos like 1 (FOSL1) transcription, and ectopic expression of FOSL1 reversed the suppressive effect of LINC01503 knockdown on NPC progression. Moreover, androgen receptor (AR)-mediated transcription activation was responsible for the overexpression of LINC01503, and AR ligand-dependent cell growth, migration, and invasion in NPC cells. Taken together, our findings reveal that AR-induced LINC01503 can promote NPC progression through the SFPQ-FOSL1 axis, which represents a novel prognostic biomarker and therapeutic target for NPC patients.