Down-regulation of lncRNA MIR31HG correlated with aggressive clinicopathological features and unfavorable prognosis in esophageal squamous cell carcinoma.

OBJECTIVE: Long non-coding RNA MIR31HG (MIR31HG) has been shown to affect numerous tumorigenesis. However, the function of MIR31HG in esophageal squamous cell carcinoma (ESCC) remains unclear. The aim of this study was to investigate whether the levels of MIR31HG could be served as a prognostic factor in patients with ESCC.

PATIENTS AND METHODS: MIR31HG expression was detected in 185 samples of surgically resected ESCC and matched normal tumor-adjacent tissues by qRT-PCR. The association between MIR31HG expression levels in tissue and characteristics was examined. Overall survival (OS) curves were conducted to compare MIR31HG level and clinical characteristics. Cox regression analysis was conducted to determine the prognostic value of MIR31HG.

RESULTS: The levels of MIR31HG were decreased in the ESCC tissues from patients with ESCC compared with the control (p < 0.01). In malignant cases, lower expression MIR31HG levels were significantly associated with poor differentiation (p < 0.001), advanced lymph node metastasis (p = 0.006), positive distant metastasis (p = 0.005) and TNM stage (p = 0.004). Kaplan-Meier analysis indicated that patients presenting with reduced MIR31HG expression exhibited poorer OS (p = 0.0002). Univariate and multivariate analysis suggested that MIR31HG expression was an independent prognostic marker for survival in patients with ESCC.

CONCLUSIONS: We observed that down-regulated MIR31HG in ESCC patients was associated with malignant clinical characteristics. MIR31HG might be considered as a potential prognostic indicator and a potential target for therapeutic targets in ESCC.