LncRNA ZFAS1 contributed to irradiation resistance in nasopharyngeal carcinoma by inhibiting hsa-miR-7-5p/ENO2

Abstract Background: In our previous research, we found that lncRNA ZFAS1 could promote nasopharyngeal carcinoma by inhibiting its downstream target axis. But we hadn’t shown whether ZFAS1 had association with irradiation resistance of NPC. In this study, we aimed to study the role of ZFAS1 in irradiation resistance of nasopharyngeal carcinoma. Methods: Bioinformatics analysis was first conducted to identify the potentially significant gene that participated in radio resistance of nasopharyngeal carcinoma. qRT-PCR was used to detect the expression of ZFAS1, miR-7-5p and ENO2 mRNA. The location of ZFAS1 was measured in cell fractions. The relationship between ZFAS1, miR-7-5p and ENO2 mRNA was validated by luciferase reporter assay and RNA pull down. Edu assay and flow cytometric apoptosis assay were conducted to observe how ZFAS1, miR-7-5p and ENO2 affected nasopharyngeal carcinoma proliferation and apoptosis under irradiation. Results：ZFAS1 was upregulated in nasopharyngeal carcinoma, which was associated with radio resistance. ZFAS1 strengthened the ability of irradiation resistance in nasopharyngeal carcinoma. ZFAS1 acted on miR-7-5p to promote ENO2 upregulation, thereby promoting the irradiation resistance. Conclusion: ZFAS1 sponged miR-7-5p to further affect ENO2 expression to augmenting the irradiation resistance in nasopharyngeal carcinoma.