Abstract: Objective To explore the expression patterns of microRNA-24 (miR-24) in cholangiocarcinoma (CCA) tissues, and analyze its prognostic value and biological function in HCC. Methods Total of 124 pairs of CCA tissues and adjacent tissues were collected, and the expression of miR-24 in the tissues was estimated by quantitative real-time RT-PCR (RT-qPCR). χ2 test was used to assess the association of miR-24 with clinicopathological characteristics of the patients. The prognostic value of miR-24 was evaluated by Kaplan-Meier survival curves and Cox regression model. The effect of miR-24 on cell proliferation, migration and invasion was investigated in CCA cell line HCCC-9810 by cell transfection with fusion expression vector pEGFP-C1-miR-24. Results The expression of miR-24 was significantly upregulated in CCA tissues compared with the paired noncancerous tissues (P<0.05), and was associated with lymph node metastasis, differentiation and TNM stage of the patients. The patients with high miR-24 expression had poor overall survival compared with those with low miR-24 expression (log-rank P<0.001). The expression of miR-24 was considered an independent prognostic factor (HR=5.518, 95%CI=2.394-12.717, P<0.001). In addition, the overexpression of miR-24 in CCA cells led to enhanced cell proliferation, migration and invasion. Conclusion The upregulated expression of miR-24 is associated with poor prognosis of CCA, and is involved in tumor progression, which may be a novel target for CCA treatment.

Key words: MiR-24, Cholangiocarcinoma, Prognosis, Proliferation, Migration