In this study, we introduced acridine orange/ethidium bromide (AO/EB) double fluorescence staining, flow cytometry analysis, TdT-mediated dUTP Nick-End Labeling (TUNEL), caspase-3 and caspase-9 to explore the potential effect of HOTAIR on apoptosis of CCA cells. Here, CASP9 is linked to cholangiocarcinoma.