Abstract
A pharmacological approach to inhibition of cyclin-dependent kinases 4 and 6 (Cdk4/6) using highly selective small molecule inhibitors has the potential to provide novel cancer therapies for clinical use. Achieving high levels of selectivity for Cdk4/6, versus other ATP-dependent kinases, presents a significant challenge. The pyrido[2,3-d]pyrimidin-7-one template provides an effective platform for the inhibition of a broad cross-section of kinases, including Cdks. It is now demonstrated that the modification of pyrido[2,3-d]pyrimidin-7-ones to include a 2-aminopyridine side chain at the C2-position provides inhibitors with exquisite selectivity for Cdk4/6 in vitro. This selectivity profile is recapitulated in cells where the most selective inhibitors create a G(1) block at concentrations up to 100-fold the IC(50) for cell proliferation. On the basis of its selectivity profile and pharmacokinetic profile, compound 43 (PD 0332991) was identified as a drug candidate for the treatment of cancer.
MeSH terms
-
Animals
-
Antineoplastic Agents / chemical synthesis*
-
Antineoplastic Agents / chemistry
-
Antineoplastic Agents / pharmacology
-
Biological Availability
-
Cell Line, Tumor
-
Cell Proliferation / drug effects
-
Cyclin-Dependent Kinase 4
-
Cyclin-Dependent Kinase 6
-
Cyclin-Dependent Kinases / antagonists & inhibitors*
-
G1 Phase / drug effects
-
Humans
-
Male
-
Piperazines / chemical synthesis*
-
Piperazines / chemistry
-
Piperazines / pharmacology
-
Proto-Oncogene Proteins / antagonists & inhibitors*
-
Pyridines / chemical synthesis*
-
Pyridines / chemistry
-
Pyridines / pharmacology
-
Pyrimidines / chemical synthesis*
-
Pyrimidines / chemistry
-
Pyrimidines / pharmacology
-
Rats
-
Rats, Sprague-Dawley
-
Structure-Activity Relationship
-
Thymidine / metabolism
Substances
-
Antineoplastic Agents
-
Piperazines
-
Proto-Oncogene Proteins
-
Pyridines
-
Pyrimidines
-
CDK4 protein, human
-
CDK6 protein, human
-
Cdk4 protein, rat
-
Cdk6 protein, rat
-
Cyclin-Dependent Kinase 4
-
Cyclin-Dependent Kinase 6
-
Cyclin-Dependent Kinases
-
palbociclib
-
Thymidine