RRFERV stabilizes TEAD1 expression to mediate nasopharyngeal cancer radiation resistance rendering tumor cells vulnerable to ferroptosis.

Abstract

Background: Long noncoding RNAs (lncRNAs) regulate various essential biological processes, including cell proliferation, differentiation, apoptosis, migration, and invasion. However, in nasopharyngeal carcinoma (NPC), the clinical significance and mechanisms of lncRNAs in malignant progression are unknown.

Methods: RNA sequencing and bioinformatic analysis were used to determine the potential function of RRFERV (radiation-resistant but ferroptosis vulnerable), and its biological effects were investigated using in vitro and in vivo experiments. Western blotting, quantitative real-time reverse transcription PCR, RNA immunoprecipitation (RIP) assays, and flow cytometry detected RRFERV expression. Ferroptosis and lipid peroxidation were added to evaluate the relationship between it and radiotherapy resistance.

Results: LncRNA-RRFERV was both highly expressed in NPC tissues and radiation-resistant cells. RRFERV is associated with poor clinical outcomes of NPC patients and stabilizes TEAD1 by competitive binding with microRNA-615-5p and microRNA-1293. RRFERV-TEAD1 signaling axis leads to malignant progression and radiotherapy resistance of NPC. Furthermore, we observed that NPC radiotherapy resistance cells exist in a fragile oxidative stress equilibrium, which makes them more sensitive to ferroptosis inducers. Surprisingly, we found that RRFERV-TEAD1 signaling axis also plays a key role in mediating the lipid peroxidation levels of NPC radiotherapy resistance cells through transcriptional activation of ACSL4/TFRC.

Conclusions: RRFERV serves as an independent prognostic factor in NPC. During the malignant progression of NPC caused by high expression of RRFERV, ferroptosis can be induced to effectively kill cancer cells and reverse the radiotherapy resistance of NPC cells, suggesting a potential treatment approach for recurrent and refractory NPC.