Accumulating evidence illustrates that many
microRNAs (
miRNAs) are abnormally expressed in
cholangiocarcinoma and play important roles in
tumorigenesis,
tumor progression and
metastasis. These
miRNAs may serve as prognostic
biomarkers and potential therapeutic targets. The aim of the present study was to identify the differentially expressed
miRNAs in
cholangiocarcinoma tissues vs. normal tissues by analyzing high‑throughput data derived from The
Cancer Genome Atlas (TCGA) database. Furthermore, we evaluated the prognostic performance of the differentially expressed
miRNAs and developed a novel three‑miRNA signature which predicted survival in
cholangiocarcinoma patients. According to the cut‑off criteria of P<0.01 and |log2FC|>1.0, a total of 100 miRNAs (54 upregulated and 46 downregulated) were found to be differentially expressed and some of them were significantly associated with clinical features. Of the above 100 miRNAs, we obtained three
miRNAs (miR‑10b, miR‑22 and miR‑551b) which were markedly related to patient overall survival (OS). Subsequently, a novel three‑miRNA signature was established and validated to be effective to predict survival. The results demonstrated that the survival rate, as well as the survival time of patients were obviously enhanced in relation to a lower
miRNA signature index. Univariate and multivariate Cox regression analyses revealed that the three‑miRNA signature was an independent prognostic factor in
cholangiocarcinoma. The reliability of the three‑miRNA signature was validated by an independent cohort from Gene Expression Omnibus (GEO). Furthermore, the functional enrichment analysis emphasized that the target genes of the aforementioned
miRNAs may be involved in a variety of pathways and processes associated with
cancer. Finally, these three
miRNAs were detected for verification of expression using RT‑qPCR, and miR‑551b was selected for the verification of biological functions in
cholangiocarcinoma cells. The results revealed that overexpression of miR‑551b decreased
cancer cell proliferation and promoted apoptosis. Collectively, the results of the present study indicated that a specific three‑miRNA signature could be considered as an alternative prognostic marker in
cholangiocarcinoma.