Long Noncoding RNA CCAT2 as a Potential Novel Biomarker to Predict the Clinical Outcome of Cancer Patients: A Meta-Analysis

Background: Colon Cancer-Associated Transcript 2 (CCAT2) has been demonstrated associated with clinical outcomes in various tumors. However, the results from each study were unfortunately insufficient and not completely consistent. Therefore, we conduct a systematic meta-analysis to evaluate the value for a feasible biomarker for metastasis and prognosis. Methods: A meta-analysis was performed using data obtained through a systematic search of PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, Wanfang database and VIP database. The pooled odds ratio (OR) and hazard ratio (HR) with 95% Confidence interval (CI ) using random-effect were used to identify the relationship of CCAT2 with clinical outcome of cancer patients. Subgroup analysis and sensitivity analysis were performed. Results: A total of 867 patients from eight studies were finally included. Patients with high CCAT2 expression underwent an increased risk of lymph node metastasis (LNM) (OR=3.09, 95% CI: 1.53-6.26) and distant metastasis (DM) (OR=7.70, 95% CI: 3.26-18.17). CCAT2 was also significantly correlated with overall survival (OS) (HR=2.19, 95%CI: 1.70-2.82) and progression-free survival (PFS) (HR=2.59, 95% CI: 1.78-3.76). Moderate heterogeneity was observed in meta-analysis for LNM. However, the results remained robust in multiple sensitivity analyses. Conclusions: High expression of CCAT2 was linked with poor clinical outcome. CCAT2 can serve as a potential molecular marker for prognosis in different types of cancers.