A novel prognostic biomarker for cholangiocarcinoma: circRNA Cdr1as.

Objective: Cholangiocarcinoma (CCA) is the second most common primary malignant hepatobiliary cancer worldwide. The circular RNA (circRNA) Cdr1as has been found to play critical roles in various cancers. However, the relationship between circRNA Cdr1as and CCA is still ambiguous. The aim of this study was to explore the expression level of Cdr1as in CCA and to further investigate the clinicopathological and prognostic value of Cdr1as.
Patients and Methods: We investigated the circRNA Cdr1as expression in 54 paired tumor and adjacent normal tissues of CCA patients by using quantitative Real-time PCR, and evaluated the relevance between Cdr1as expression level and the clinicopathological features. We further assessed the association of Cdr1as expression with overall survival and its prognostic efficacy.
Results: The expression of circRNA Cdr1as in tumor tissues was higher than that in adjacent normal tissues. The overexpression of Cdr1as was closely associated with the advanced TNM stage, lymph node invasion, and postoperative recurrence. The overall survival of CCA patients with high Cdr1as expression was worse than that of the CCA patients with low Cdr1as expression. According to multivariate analysis, the Cdr1as expression could be considered as an independent prognostic biomarker for cholangiocarcinoma with acceptable sensitivity and specificity.
Conclusions: Our finding suggested that circRNA Cdr1as may serve as a potential vicious molecular biomarker to predict the aggressive tumor progression and worse prognosis for CCA patients.