Since the cell cycle regulator protein p57KIP2 (encoded by the CDKN1C gene, hereafter p57) had been reported to mediate synergistic induction of apoptosis by combined HDAC and BET inhibition in pancreatic ductal adenocarcinoma [8], we evaluated its expression in four UCCs after treatment. The gene discussed is CDKN1C; the disease is pancreatic ductal adenocarcinoma.