XIST as a valuable biomarker for prognosis and clinical parameters in diverse tumors: a comprehensive meta- and...

Long non-coding RNA (lncRNA) X inactivate-specific transcript (XIST) has been found dysregulated in a variety of human tumors and influenced the clinicopathologic characteristics in cancer patients. Therefore, we systematically searched relevant literature that has identified the correlation of lncRNA XIST expression and clinical outcomes of tumor patients and conducted this meta-analysis to elucidate the clinical prognostic value of long noncoding RNA XIST in human tumors. A comprehensive literature search was performed from PubMed, Web of Science, EMBASE, and Cochrane library databases up to August 1, 2019. Pooled hazard ratios (HRs) or odds ratios (ORs) with a 95% confidence interval (95% Cl) were calculated to evaluate the prognosis, as well as the clinicopathological parameters of XIST, respectively. We also further validated this meta-analysis using The Cancer Genome Atlas (TCGA) dataset. The outcome revealed that XIST overexpression in tumor tissue was interacted to a poor overall survival (OS) (HR=0.52, 95% CI: 0.44-0.61, p<0.0001), disease-free survival (DFS) (HR=0.50; 95% CI: 0.36-0.69, p<0.0001), tumor type (digestive system malignancies, HR=0.53; 95% CI: 0.44-0.63, p<0.0001); nondigestive system malignancies, HR=0.48; 95% CI: 0.34-0.67, p<0.0001), lymph node metastasis(LNM) (OR=0.61, 95% CI: 0.37-1.00; p=0.048), differentiation (OR=1.46; 95% CI: 0.94-2.29; p=0.096), distant metastasis (DM) (OR=0.48, 95% CI: 0.31-0.75; p=0.001), tumor size (OR=0.59, 95% CI: 0.38-0.92; p=0.019), and tumor stage (OR=2.36; 95% CI: 1.62-3.43; p<0.001). XIST could have potential value in early diagnosis and result in prediction and provide a novel view for the therapeutic target in clinical application.