CASP9 and cholangiocarcinoma: Taken together, these results suggest that Lan C can not only activate caspase-9 and caspase-3 by inducing an increase in ROS, leading to a decrease in mitochondrial membrane potential, but also inhibit STAT3 expression, resulting in a downregulation of Bcl-2 and Bcl-xl expression and an increase in Bax expression, thus promoting apoptosis in cholangiocarcinoma cells.