Long noncoding RNA ZFAS1 promotes tumorigenesis and metastasis in nasopharyngeal carcinoma by sponging miR‐892b to up‐regulate LPAR1 expression

OBJECTIVE: In this study, we explored the NPC‐specific expression of ZFAS1 and the mechanism of ZFAS1‐mediated growth, aggressiveness and tumorigenesis in NPC. METHODS: The expression profile of lncRNAs was detected in NPC tissues and matching para‐carcinoma tissues using microarray analysis. LncRNA‐miRNA and miRNA‐mRNA interaction networks were constructed using the miRcode v11 and TargetScanHuman v7.2 web server and then validated using dual‐luciferase assay. Western blot and RT‐qPCR were performed to detect protein and RNA expression. The effects of ZFAS1, miR‐892b and LPAR1 dysregulation on the proliferative, migratory and invasive abilities of NPC cells were observed using colony formation, cell counting kit‐8 (CCK‐8) and transwell assays in vitro. In vivo, a xenograft nude mouse model was established to detect the impact of ZFAS1 dysregulation on the tumorigenicity of NPC cells. RESULTS: The expression of multiple lncRNAs, of which ZFAS1 was up‐regulated, was dysregulated in NPC tissues. ZFAS1 directly targeted miR‐892b, and miR‐892b negatively regulated the expression of downstream LPAR1. The proliferation, migration and invasion of NPC cells could be largely enhanced by the downregulation of miR‐892b as well as the up‐regulation of ZFAS1 and LPAR1, while the overexpression of miR‐892b and the downregulation of ZFAS1 and LPAR1 decreased these abilities. In nude mice, the growth of tumour xenografts formed by HONE1 cells was significantly suppressed when ZFAS1 was silenced. CONCLUSION: The study demonstrated that lncRNA ZFAS1 may act as a promoter of tumorigenesis and metastasis in nasopharyngeal carcinoma, by up‐regulating the expression of LPAR1 in a miR‐892b‐dependent manner.