Clinical prognostic value of metastasis-associated lung adenocarcinoma transcript 1 in various human cancers: an updated meta-analysis.

Background: Many studies have investigated the prognostic value of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in human cancers. However, these studies were often limited by small sample sizes. Therefore, we performed this updated meta-analysis to summarize the potential value of MALAT1 as a biomarker for early treatment and to predict survival in various human malignant neoplasms, through the inclusion of the latest literature and improved methodology.

Methods: Twelve eligible articles were systematically obtained from PubMed, Medline, Embase, Web of Science, China National Knowledge Infrastructure and the Cochrane Library, from inception up to June 30, 2015. Survival was assessed using pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs).

Results: By combining the results of 12 studies, we found elevated MALAT1 expression was associated with poor survival in most cancers, with a pooled HR of 1.90 (95% CI, 1.56-2.30) for overall survival (OS) and 3.06 (95% CI, 2.06-4.56) for recurrence-free survival/disease-free survival. Subgroup analyses according to ethnicity, tumor type, assay method, sample size, HR-calculation method and analysis type did not affect the predictive role of MALAT1 for OS in various cancer types. Further, by combining results from studies that used multivariate analyses, we found elevated MALAT1 was an independent prognostic factor for OS (HR = 1.98; 95% CI, 1.58-2.48).

Conclusions: MALAT1 could serve as a potential prognostic biomarker in various cancers and may be a potential therapeutic target for the treatment and early detection of recurrence.