Wee1

Wee1 inhibitors act on a nuclear tyrosine kinase that delays entry into mitosis after DNA damage. Wee1 phosphorylates cyclin-dependent kinase 1 (CDK1) on tyrosine 15 and so keeps the CDK1-cyclin B complex inactive, as shown for the human enzyme in 1992. Protein kinase membrane-associated tyrosine/threonine 1 (PKMYT1) phosphorylates CDK1 on both threonine 14 and tyrosine 15. Blocking these kinases pushes cells with damaged DNA into premature mitosis. This effect is studied together with DNA-damaging agents, often in tumor cells that lack a functional G1 checkpoint. Adavosertib is a selective Wee1 inhibitor, whereas PD0166285 and PD 407824 also block checkpoint kinases listed under Chk. XH-30 inhibits PKMYT1, and HEMTAC WEE1 degrader-1 removes Wee1 by targeted degradation.