Adavosertib (MK-1775)

2 years -80 in solvent

Orally

WiDr, NCI-H1299, TOV21G, and HeLa

Dissolved in DMSO, final concentrations ca.10 uM

Prepared in a vehicle of 0.5% methylcellulose solution

MK-1775 inhibits Wee1 kinase in an ATP-competitive manner. Compared to Wee1, MK-1775 displays 2- to 3-fold less potency against Yes with IC50 of 14 nM, 10-fold less potency against seven other kinases with >80% inhibition at 1 uM, and >100-fold selectivity over human Myt 1, another kinase that inhibits cyclin-dependent kinase 1 (CDC2) by phosphorylation at an alternative site (Thr14). By abrogating the DNA damage checkpoint via blockade of Wee1 activity in WiDr cells bearing mutated p53, MK-1775 treatment inhibits the basal phosphorylation of CDC2 at Tyr15 (CDC2Y15) with EC50 of 49 nM, and suppresses gemcitabine-, carboplatin- or cisplatin-induced phosphorylation of CDC2 and cell cycle arrest in a dose-dependent manner, with EC50 of 82 nM and 81 nM, 180 nM and 163 nM, as well as 159 nM and 160 nM, respectively. MK-1775 treatment alone at 30-100 nM has no significant antiproliferative effect in WiDr and H1299 cells, whereas MK-1775 at 300 nM, sufficient to inhibit Wee1 by >80%, displays moderate but significant antiproliferative effects by 34.1% in WiDr cells and 28.4% in H1299 cells. [1]

24 hours

Cells are treated with or without gemcitabine for 24 hours, then with MK-1775 for an additional 24 hours. Cell viability is determined with a WST-8 kit using SpectraMax. Cellular caspase-3/7 activities are determined with a Caspase-3/7 Glo kit.

Adavosertib (MK-1775, AZD1775) is a potent and selective Wee1 inhibitor with IC50 of 5.2 nM in a cell-free assay; hinders G2 DNA damage checkpoint. Phase 2.

First reported Wee1 inhibitor