Prognostic and clinicopathological significance of CCAT2 in Chinese patients with various tumors.

Background: Colon cancer-associated transcript 2 (CCAT2) as a long noncoding RNA (lncRNA) is overexpressed and plays a significant prognostic role in patients with tumors. The present study aimed to comprehensively evaluate the clinical value of CCAT2 in the Chinese population, as a potential prognostic marker in multiple cancers.

Methods: A systematic search of eligible studies was conducted in the PubMed, Web of Science, Cochrane Library, Wanfang and the China National Knowledge Infrastructure databases as of March 31, 2017. Approximately 1,711 tumor patients from 16 eligible studies were selected. Analyses of the pooled data were performed, and the odds ratio (OR) or hazard ratio (HR) and the 95% confidence interval (95% CI) were calculated and summarized to evaluate the strength of this association using a fixed- or random-effects model.

Results: Overall analyses showed that increased CCAT2 expression was associated with a higher risk of lymph node metastasis (LNM), an increased potential for distant metastasis (DM) and higher clinical stage (p<0.001 for LNM, p = 0.001 for DM, p<0.001 for clinical stage). HR and the 95% CI for overall survival (OS) were assessed to pool the effect size using a fixed-effects model. A significant association was observed between increased CCAT2 expression and poor OS (pooled HR = 1.91, 95% CI, 1.63-2.22, p<0.001).

Conclusions: These results indicate that CCAT2 is a biomarker to predict tumor progression and a potential prognostic marker in multiple cancers. Additional well-designed clinical studies are needed to validate these findings.