Clinical significance of H19 as a prognostic factor in human cancer: a systematic review and meta-analysis

Background: LncRNA H19 (H19) is known to play a crucial role in tumor development, progression, and prognosis. Methods: A comprehensive meta-analysis was performed by searching PubMed, Medline and EMBASE online databases to retrieve studies relevant to the expression of H19 and its prognostic value in cancer patients. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) for survival were calculated as the effect size to quantify the prognostic value of H19 in human cancers. Results: Twelve studies with a total of 4500 patients were included in this meta-analysis. Analysis results showed that high expression of H19 in cancer patients was a negative predictor for overall survival (OS) with a pooled HR of 1.167 (95% CI: 1.055-1.291, P = 0.003). No significant association was found between H19 expression and cancer patients' disease-free survival (DFS) (HR = 1.092, 95% CI: 0.866-1.377, P = 0.459). Subgroup analysis results showed that country, method of measuring H19 expression, publication quality, and statistical analysis method did not affect the predictive value of H19 in cancer prognosis. Heterogeneity existed among the studies but we failed to identify the source of the heterogeneity. Sensitivity analysis indicated that the results of this meta-analysis were reliable. Begg's and Egger's test found the publication bias between H19 and OS in cancer, but the results of trim and fill procedure were similar with the general results. Conclusion: High expression of H19 may be a predictor of poor prognosis in patients with cancer.