Enhanced expression of lncRNA TP73-AS1 predicts adverse phenotypes for cholangiocarcinoma and exerts oncogenic properties in vitro and in vivo.

Cholangiocarcinoma (CCA) is one of the most aggressive malignancies with increasing incidence worldwide. Various evidence documents that abnormally expressed long non-coding RNAs (lncRNAs) play important roles in tumorigenesis and progression. TP73-AS1 is a novel cancer-related lncRNA that contributes to the development of several malignancies. However, its clinical value and potential effects on CCA remains unknown. RT-qPCR was used to measure the expression levels of TP73-AS1 in CCA tissues and paired non-tumor tissues and the association between TP73-AS1 expression and clinicopathological characteristics was analyzed. In addition, the functional roles of TP73-AS1 in CCA were detected both in vitro and in vivo. The results illustrated that TP73-AS1 transcription is enhanced in both CCA tissue samples and cell lines, and this upregulation is closely associated with larger tumor size (p=0.008) and advanced TNM stage (p=0.026) in patients with CCA. For the part of functional assays, silencing of TP73-AS1 could attenuate CCA cell growth both in vitro and in vivo. Additionally, silencing of TP73-AS1 facilitates apoptosis via activating caspase-3 and caspase-9. Importantly, TP73-AS1 expression did not affect HIBEC cell growth and apoptosis. Moreover, TP73-AS1 could also facilitate migration and invasion potential of CCA cells. Collectively, these findings may help to develop a potential therapeutic target for the patients with CCA.