Long non‐coding RNA HOTAIR is an independent prognostic marker for nasopharyngeal carcinoma progression and survival

Identification of new nasopharyngeal carcinoma (NPC) biomarkers is of great clinical value for the diagnosis and treatment of NPC. HOTAIR, a cancer-related long non-coding RNA, was tested and its prognostic value for NPC was evaluated. As determined using in situ hybridization (ISH), 91 of 160 (56.87%) paraffin-embedded NPC biopsies showed high expression levels of HOTAIR (staining index score ≥ 6). HOTAIR was upregulated in tumors with a large size (P = 0.021), more advanced clinical stage (P = 0.012) and increased lymph node tumor burden (P = 0.005). Quantified using real-time PCR, HOTAIR expression levels in fresh tissue and paraffin-embedded samples were 5.2 ~ 48.4-fold higher compared with non-cancer tissue samples. Moreover, HOTAIR expression levels increased with clinical stage progression, which was consistent with ISH findings in the paraffin-embedded tissue. Most importantly, NPC patients with higher HOTAIR levels had a poor prognosis for overall survival using univariate and multivariate analysis. In addition, HOTAIR mediated the migration, invasion and proliferation of NPC cells in vitro. HOTAIR is a potential biomarker for the prognosis of NPC, and dysregulation of HOTAIR might play an important role in NPC progression.