Prognostic significance of long noncoding RNA TTN‐AS1 in various malignancies

BACKGROUND: Increasing evidence has demonstrated that high TTN‐AS1 expression is highly related to poor prognosis in diverse human cancers. However, the findings concerning the prognostic value of TTN‐AS1 were inconsistent, as these conclusions were usually drawn with relatively small sample sizes. Hence, this meta‐analysis proposes to investigate the prognostic significance of TTN‐AS1 in multiple malignancies systematically. METHODS: Web of Science, Springer, Embase, PubMed, Cochrane Library, and Scopus databases were comprehensively searched to retrieve studies related to the TTN‐AS1 expression with the prognosis of malignancies. The significance of the TTN‐AS1 in cancers was estimated by hazard ratios (HRs) or odds ratios (ORs). Additionally, the Gene Expression Profiling Interactive Analysis (GEPIA) analysis tool was used to strengthen our results further. RESULTS: Twenty studies involving 17 different cancers and 1330 patients were recruited into this meta‐analysis. The research revealed that high TTN‐AS1 expression was remarkably associated with unfavorable overall survival (OS) (HR = 2.07, 95%CI [1.78, 2.41], p < .00001) when compared with low TTN‐AS1 expression in malignancies. Additionally, elevated TTN‐AS1 expression significantly contributed to lymph node metastasis (OR = 4.09, 95%CI [3.08, 5.44], p < .0001), larger tumor size (OR = 2.42, 95%CI [1.56, 3.77], p < .0001), worse tumor differentiation (OR = 0.36, 95%CI [0.22, 0.59], p < .0001) and more advanced tumor stage (OR = 0.29, 95%CI [0.22, 0.38], p < .0001) with low or no heterogeneity existing. Moreover, high TTN‐AS1 expression was connected with worse disease‐free survival in five different cancers based on the GEPIA online database. CONCLUSIONS: The results of this meta‐analysis support that high TTN‐AS1 expression significantly correlates with worse prognosis in various cancers. Therefore, TTN‐AS1 may be considered as a novel biomarker for malignancies.