Prognostic value of lncRNA HOTAIR in colorectal cancer: a meta-analysis

HOX transcript antisense intergenic RNA (HOTAIR) is one of the most studied long noncoding RNAs (lncRNAs) and is aberrantly expressed in colorectal cancer (CRC). We thus performed a comprehensive study based on meta-analysis and validation of the TCGA database to investigate clinicopathological and prognostic value of HOTAIR in CRC. Six studies enrolling 629 CRC patients were included in the analysis. The results indicated that high HOTAIR expression predicted worse OS (hazard ratio [HR] = 2.46, 95% confidence interval [CI]: 1.82-3.32, P < 0.01) and RFS (HR = 1.97, 95% CI: 1.27-3.05, P < 0.01) for CRC patients. High HOTAIR expression was also significantly associated with venous invasion (OR = 2.53, 95% CI: 1.12-5.68, P = 0.02), advanced tumor infiltration (OR = 3.35, 95% CI: 1.34-8.42, P = 0.01) and distant metastasis (OR = 5.52, 95% CI: 1.22-25.01, P = 0.03). Then, the results were validated by the TCGA database, showing that the up-regulated expression of HOTAIR was significantly related to poor OS (P = 0.01) and RFS (P = 0.04) in CRC. Our meta-analysis indicated that high HOTAIR expression was closely associated with poor clinical outcomes and could be a reliable prognostic biomarker for CRC patients.