Danusertib (PHA-739358)S1107

Danusertib inhibits the activities of other kinases such as FGFR1, Abl, Ret and Trka, with IC50 of 47 nM, 25 nM, 31 nM and 31 nM, respectively. In a cell assay, after treatment of wild-type and p53-deficient MEFs with Danusertib, the wild-type cells undergo an arrest in mitosis (4N) that is maintained for up to 48 h. The p53-deficient cells on the other hand do not arrest at the 4N DNA stage, but continues with additional rounds of DNA synthesis to become >8N. Treatment with Danusertib results in an increase in p53 protein levels and an associated increase in p21 protein, which is known to be transcriptionally regulated by p53. ^[1] Increasing concentrations of Danusertib produces a dose-dependent reduction of cell growth after 48 hours in BCR-ABL-positive (K562, BV173) and BCR-ABL-negative (HL60) cells. ^[3]