CD24 and familial pancreatic carcinoma: PARP1 binds to, and inhibits DDX5 by ADP-ribosylating DDX5 in pancreatic cancer cells (Fig. 3C1), which can be abolished by PARP1 inhibitor, talazoparib, while PARP1 inhibition increased DDX5 expression and binding to the CD24 promoter [66].