A selective chemical probe for exploring the role of CDK8 and CDK19 in human disease.
There is unmet need for chemical tools to explore the role of the Mediator complex in human pathologies ranging from cancer to cardiovascular disease. Here we determine that CCT251545, a small-molecule inhibitor of the WNT pathway discovered through cell-based screening, is a potent and selective chemical probe for the human Mediator complex-associated protein kinases CDK8 and CDK19 with >100-fold selectivity over 291 other kinases. X-ray crystallography demonstrates a type 1 binding mode involving insertion of the CDK8 C terminus into the ligand binding site. In contrast to type II inhibitors of CDK8 and CDK19, CCT251545 displays potent cell-based activity. We show that CCT251545 and close analogs alter WNT pathway-regulated gene expression and other on-target effects of modulating CDK8 and CDK19, including expression of genes regulated by STAT1. Consistent with this, we find that phosphorylation of STAT1(SER727) is a biomarker of CDK8 kinase activity in vitro and in vivo. Finally, we demonstrate in vivo activity of CCT251545 in WNT-dependent tumors.
School of Bioscience, Cardiff University, Cardiff, UK.
Trevor
T
Dale
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Paul A
PA
Clarke
Merck KGaA, Merck Serono, Darmstadt, Germany.
Christina
C
Esdar
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Dennis
D
Waalboer
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Olajumoke
O
Adeniji-Popoola
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Maria-Jesus
MJ
Ortiz-Ruiz
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Aurélie
A
Mallinger
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Rahul S
RS
Samant
Merck KGaA, Merck Serono, Darmstadt, Germany.
Paul
P
Czodrowski
Merck KGaA, Merck Serono, Darmstadt, Germany.
Djordje
D
Musil
Merck KGaA, Merck Serono, Darmstadt, Germany.
Daniel
D
Schwarz
Merck KGaA, Merck Serono, Darmstadt, Germany.
Klaus
K
Schneider
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Mark
M
Stubbs
School of Bioscience, Cardiff University, Cardiff, UK.
Ken
K
Ewan
School of Bioscience, Cardiff University, Cardiff, UK.
Elizabeth
E
Fraser
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Robert
R
TePoele
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Will
W
Court
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Gary
G
Box
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Melanie
M
Valenti
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Alexis
A
de Haven Brandon
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Sharon
S
Gowan
Merck KGaA, Merck Serono, Darmstadt, Germany.
Felix
F
Rohdich
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Florence
F
Raynaud
Merck KGaA, Merck Serono, Darmstadt, Germany.
Richard
R
Schneider
Merck KGaA, Merck Serono, Darmstadt, Germany.
Oliver
O
Poeschke
Merck KGaA, Merck Serono, Darmstadt, Germany.
Andree
A
Blaukat
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Paul
P
Workman
Merck KGaA, Merck Serono, Darmstadt, Germany.
Kai
K
Schiemann
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Suzanne A
SA
Eccles
Merck KGaA, Merck Serono, Darmstadt, Germany.
Dirk
D
Wienke
Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, SW7 3RP.
Julian
J
Blagg
D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D056850:Cyclin-Dependent Kinase 8 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D015335:Molecular Probes / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D047428:Protein Kinase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D011725:Pyridines / Q000737:chemistry / Q000494:pharmacology*; D013141:Spiro Compounds / Q000737:chemistry / Q000494:pharmacology*
C000606523:CCT251545; D015335:Molecular Probes; D047428:Protein Kinase Inhibitors; D011725:Pyridines; D013141:Spiro Compounds; C584437:CDK19 protein, human; C095686:CDK8 protein, human; D056850:Cyclin-Dependent Kinase 8; D018844:Cyclin-Dependent Kinases