Long non-coding RNA-LET can indicate metastasis and a poor prognosis: a meta-analysis.

Introduction: Recent studies have reported that long non-coding RNA low expression in tumor (lncRNA-LET) was down-regulated in several cancers. The current meta-analysis aims to determine whether lncRNA-LET can be used as a potential biomarker for metastasis and prognosis.
Evidence Acquisition: We collected all relevant papers by searching multiple electronic databases (PubMed, EMBASE, Google Scholar, CNKI, Wanfang Database) and explored the association between the expression levels of lncRNA-LET and lymph node metastasis (LNM), distant metastasis (DM) and overall survival (OS).
Evidence Synthesis: A total of 383 patients from four studies were finally included. The meta-analysis results showed that LNM occurred more frequently in patients from the lncRNA-LET low expression group than in patients from the lncRNA-LET overexpression group (OR=4.56, 95% CI 2.92-7.12, P<0.00001), and a similar result was observed between lncRNA-LET expression and DM (OR=4.77, 95% CI 2.29-9.94, P<0.0001). Additionally, we found that patients with low expression of lncRNA-LET had a poorer OS than those with lncRNA-LET overexpression (HR=2.39, 95% CI 1.57-3.21, P=0.000).
Conclusions: lncRNA-LET may serve as a common molecular marker for metastasis and prognosis in human cancers.