The prognostic value of HOTAIR for predicting long-term prognosis of patients with gastrointestinal cancers.

Background: Increased expression of HOX transcription antisense RNA (HOTAIR) has been reported to be associated with unfavorable prognosis in cancer patients. Several studies have evaluated the significance of HOTAIR in the development and progression of gastrointestinal cancers (GICs).

Methods: Systematic literature retrieval was performed by searching keywords in several electronic databases, including PubMed, Embase, Web of Science, CNKI, Springer, Google Scholar, and GEO. Relevant articles on association between HOTAIR expression levels and prognosis in patients with GIC were collected and screened with eligible criteria. The RevMan 5.2 software and Stata SE12.0 software was applied.

Results: A total of 1297 patients from 15 eligible articles were included in this meta-analysis. The results revealed that increased expression of HOTAIR was significantly associated with shorter overall survival (OS) in GIC patients [hazard ratio (HR) = 1.93, 95% CI: 1.64-2.26], as well as poorer disease-free survival (DFS) (HR = 2.79; 95% CI: 1.38-5.63). Additionally, the pooled odds ratio (OR) indicated that increased HOTAIR was associated with clinicopathological parameters, including lymph node metastasis (OR = 2.48, 95% CI: 1.71-3.61), distant metastasis (OR = 4.34, 95% CI: 2.12-8.91), poor tumor differentiation (OR = 2.90, 95% CI: 1.45-5.80), lymphovascular invasion (OR = 2.86, 95% CI: 1.83-4.46), high depth of tumor invasion (OR = 2.07, 95% CI: 1.36-3.16), and poor clinical stage (OR = 2.72, 95% CI: 1.70-4.35). In survival analysis through the Kaplan-Meier plotter database, enhanced level of HOTAIR was associated with better OS and DFS in gastric cancer patients.

Conclusions: High expression level of HOTAIR was related to poor clinical outcome of GIC patients. The HOTAIR could be applied as potential biomarker for assessing the prognosis. Further well-designed studies should be performed to verify the clinical applications of HOTAIR in GIC.