Upregulation of lncRNA LINC00473 promotes radioresistance of HNSCC cells through activating Wnt/β-catenin signaling pathway.

OBJECTIVE: LncRNA LINC00473 was reported to be upregulated in human cancers. Whereas, the role of LINC00473 in head and neck squamous cell carcinoma (HNSCC) and radiotherapy remains elusive. PATIENTS AND METHODS: Gene array analysis was performed to detect lncRNA LINC00473. Then, the expression of LINC00473 in HNSCC 78 pairs of tissues and cell lines was measured by qRT-PCR assay. To explore the detailed functions of LINC00473 on cell proliferation, MTT and colony formation assays were conducted. We also investigated the influence of LINC00473 expression on radioresistance of HNSCC cells. Western blot assay was used to confirm the relationship between LINC00473 and Wnt/β-catenin signaling pathway. Furthermore, the effects of x-ray treatment on LINC00473 expression and Wnt/β-catenin signaling pathway were detected by Western blot assay. RESULTS: LncRNA LINC00473 was upregulated in HNSCC tissues and cell lines. Functional assays showed that LINC00473 acted as oncogene to promote cell proliferation and inhibit apoptosis. In addition, downregulation of LINC00473 enhanced the sensitivity of radiotherapy for HNSCC cells. Furthermore, Western blot assays demonstrated that Wnt/β-catenin signaling pathway was inhibited by LINC00473 knockdown. Notably, Western blot assay revealed that x-ray treatment suppressed the activity of Wnt/β-catenin signaling pathway after LINC00473 knockdown. CONCLUSIONS: These data suggested that the upregulation of lncRNA LINC00473 promotes the radioresistance of HNSCC cells through activating Wnt/β-catenin signaling pathway.