Prognostic Role Of LncRNA HOTAIR In Esophageal Squamous Cell Carcinoma:a Meta-analysis

Objective:Long non-coding RNA(lncRNA)HOX transcript antisense intergenic RNA(HOTAIR)is overexpressed in many kinds of cancer patients and might be implicated in cancer development and progression.However,the relationship between the expression of HOTAIR and clinical prognosis is not well established.Several investigations have suggested that HOTAIR may be related to poor prognosis in esophageal squamous cell carcinoma(ESCC).This study was designed to clarify the prognostic role of HOTAIR in ESCC by meta analysis.Methods:PubMed,MEDLINE,EMBASE and the Cochrane Central Register of Controlled Trials databases were used to identify studies evaluating the prognostic significance of HOTAIR in ESCC,published before December 31,2017.Cochrane collaboration recommended assessment tools was used to evaluate the literature quality.Date analysis was performed by Rev Man5.3 software.Fixed-effects/random-effects models were used to calculate pooled hazard ratios(HRs)for overall survival(OS),lymph node metastasis(LNM)and cancer stage.The outcomes were described by forest plot and funnel plot.The publication bias exists if the asymmetry of funnel figure.Results:According to the subject key words,491 papers were selected undergone the completion of the literature retrieval.After intensive reading and selected step by step,a total of 7 published studies including 646 ESCC patients were enrolled in this meta-analysis excluding which are not consistent with the standards,interventions,statistical methods,and reporting data.The meta analysis revealed that high HOTAIR expression in ESCC tissue was significantly correlated with poor overall survival(HR=2.37,95%CI,1.80-3.11,P<0.001)and lymph node metastasis(RR=1.96,95%CI,1.07-3.60,P=0.03),and without heterogeneity(I~2=0%,P=0.50).However,the results did not find out a significant relationship between HOTAIR expression and tumor stage(RR=1.98,95%CI,0.62-6.37,P=0.25),with significant heterogeneity(I~2=93%,P<0.001),which showed that the result was low reliability.Conclusion:High expression of lncRNA HOTAIR in ESCC tissue indicated poor prognosis for patients,and HOTAIR might be a predictive factor for ESCC metastasis.However,this study can not completely avoid the existence of bias,and well-designed studies with large sample sizes are necessary to further confirm the correlation between HOTAIR and the clinical outcomes of ESCC in various ethnic populations.