BBC3 and cholangiocarcinoma: To determine whether the induction of cell death in cisplatin-treated cholangiocarcinoma cells was due, in part, to regulation of PUMA expression, QBC939 and FRH 0201 cells were exposed to a cisplatin concentration of 20 μg/mL for 6 h, after which time the cisplatin-treated cells were transfected PUMA siRNA for 72 h to knock down PUMA.