Long noncoding RNA ANRIL as a novel biomarker of lymph node metastasis and prognosis in human cancer: a meta-analysis

Dysregulation of the long noncoding RNA antisense noncoding RNA in the INK4 locus (ANRIL) has been reported in various solid tumors. We performed a synthetic analysis to clarify the clinical value of ANRIL as a prognostic indicator in malignant tumors. Article collection was conducted using several electronic databases, including PubMed, Web of Science, Medline, OVID and Embase (up to July 14 2017). Thirteen original studies and 1172 total patients were included in the meta-analysis. There was a significant positive association between the high expression level of ANRIL and lymph node metastasis (OR = 4.77, 95% CI: 2.30–9.91, P < 0.001) by a random effects model (I(2) = 73.2, P = 0.001) and negative association with poor grade cancer (OR = 3.44, 95% CI: 1.68–7.08) by a random-effects model (I(2) = 77.9, P = 0.000). The results of the meta-analysis showed that overexpression of ANRIL is positively related to poor overall survival (OS) (pooled HR = 2.12, 95% CI: 1.78–2.53, P < 0.0001) by a fixed-effects model (I(2) = 0%, P = 0.654) and poor disease-free survival (DFS) (HR = 2.10, 95% CI: 1.51–2.92, P < 0.001) by a fixed-effects model (I(2) = 13.3%, P = 0.315) in human solid cancers. Statistically significant associations were also found with cancer type, analysis method, sample size, and follow-up time. In conclusion, ANRIL may serve as a novel biomarker for indicating lymph node metastasis and prognosis in human cancer.