Upregulation of long noncoding RNA XIST is associated with poor prognosis in human cancers.

Growing evidence from recent studies has shown that the X-inactive specific transcript (XIST), a well-known long noncoding RNA involved in early embryonic development, is aberrantly regulated in various human cancers. However, the prognostic value of XIST in cancers remains uncharacterized. In this study, we searched PubMed, Web of Science, and Embase to collect all relevant studies, and a meta-analysis was performed to explore the association of XIST expression with overall survival (OS) and clinicopathological parameters. We demonstrated that high XIST expression was associated with poor OS (hazard ratio = 1.76; 95% confidence intervals [CI], 1.56-1.98; p < 0.001). In addition, increased XIST expression was found to be associated with lymph node metastasis (odds ratio [OR] = 2.06; 95% CI, 1.46-1.90; p < 0.001), distant metastasis (OR = 2.93; 95% CI, 2.00-4.28; p < 0.001), tumor size (OR = 2.66; 95% CI, 1.86-3.81; p < 0.001), poor differentiation (OR = 1.45; 95% CI, 1.00-2.10; p = 0.049), and advanced tumor stage (OR = 3.35; 95% CI, 2.25-5.00; p < 0.001), but not with age (OR = 0.82; 95% CI, 0.59-1.15; p = 0.251) or gender (OR = 0.92; 95% CI, 0.70-1.19; p = 0.512). Our meta-analysis showed that XIST may be a useful common biomarker for predicting prognosis in patients with cancer.