Biomaterial Database

3-Aminopyrazole inhibitors of CDK2/cyclin A as antitumor agents. 2. Lead optimization. 2005

Paolo Pevarello, and Maria Gabriella Brasca, and Paolo Orsini, and Gabriella Traquandi, and Antonio Longo, and Marcella Nesi, and Fabrizio Orzi, and Claudia Piutti, and Pietro Sansonna, and Mario Varasi, and Alexander Cameron, and Anna Vulpetti, and Fulvia Roletto, and Rachele Alzani, and Marina Ciomei, and Clara Albanese, and Wilma Pastori, and Aurelio Marsiglio, and Enrico Pesenti, and Francesco Fiorentini, and Jim R Bischoff, and Ciro Mercurio

Department Chemistry, Nerviano Medical Sciences, BU-Oncology and BU-Preclinical Science, Viale Pasteur 10, 20014 Nerviano (MI), Italy. paolo.pevarello@nervianoms.com

Inhibitors of cyclin-dependent kinases (CDK) such as CDK2/cyclin A-E are currently undergoing clinical trials to verify their potential as new anticancer agents. In a previous article we described the lead discovery process of a 3-aminopyrazole class of CDK2/cyclin A-E inhibitors. The endpoint of this process was PNU-292137, a compound endowed with in vivo antitumor activity in a mouse tumor xenograft model. We optimized this lead compound to improve some physicochemical properties, notably solubility and plasma protein binding. This lead optimization process brought us to the discovery of (2S)-N-(5-cyclopropyl-1H-pyrazol-3-yl)-2-[4-(2-oxo-1-pyrrolidinyl)phenyl]propanamide (PHA-533533, 13), a compound with a balanced activity vs druglike profile. Compound 13 inhibited CDK2/cyclin A with a K(i) of 31 nM, counteracting tumor cell proliferation of different cell lines with an IC(50) in the submicromolar range. Solubility was improved more than 10 times over the starting lead, while plasma protein binding was decreased from 99% to 74%. With exploitation of this globally enhanced in vitro profile, 13 was more active than PNU-292137 in vivo in the A2780 xenograft model showing a tumor growth inhibition of 70%. Proof of mechanism of action was obtained in vivo by immunohistochemical analysis of tumor slices of 13-treated vs untreated animals.

UI	MeSH Term	Description	Entries
D008819	Mice, Nude	Mutant mice homozygous for the recessive gene "nude" which fail to develop a thymus. They are useful in tumor studies and studies on immune responses.	Athymic Mice,Mice, Athymic,Nude Mice,Mouse, Athymic,Mouse, Nude,Athymic Mouse,Nude Mouse
D008958	Models, Molecular	Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.	Molecular Models,Model, Molecular,Molecular Model
D010539	Permeability	Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.	Permeabilities
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011720	Pyrazoles	Azoles of two nitrogens at the 1,2 positions, next to each other, in contrast with IMIDAZOLES in which they are at the 1,3 positions.
D011760	Pyrrolidinones	A group of compounds that are derivatives of oxo-pyrrolidines. A member of this group is 2-oxo pyrrolidine, which is an intermediate in the manufacture of polyvinylpyrrolidone. (From Merck Index, 11th ed)	Pyrrolidinone,Pyrrolidone,Pyrrolidones
D001798	Blood Proteins	Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.	Blood Protein,Plasma Protein,Plasma Proteins,Serum Protein,Serum Proteins,Protein, Blood,Protein, Plasma,Protein, Serum,Proteins, Blood,Proteins, Plasma,Proteins, Serum
D004354	Drug Screening Assays, Antitumor	Methods of investigating the effectiveness of anticancer cytotoxic drugs and biologic inhibitors. These include in vitro cell-kill models and cytostatic dye exclusion tests as well as in vivo measurement of tumor growth parameters in laboratory animals.	Anticancer Drug Sensitivity Tests,Antitumor Drug Screens,Cancer Drug Tests,Drug Screening Tests, Tumor-Specific,Dye Exclusion Assays, Antitumor,Anti-Cancer Drug Screens,Antitumor Drug Screening Assays,Tumor-Specific Drug Screening Tests,Anti Cancer Drug Screens,Anti-Cancer Drug Screen,Antitumor Drug Screen,Cancer Drug Test,Drug Screen, Anti-Cancer,Drug Screen, Antitumor,Drug Screening Tests, Tumor Specific,Drug Screens, Anti-Cancer,Drug Screens, Antitumor,Drug Test, Cancer,Drug Tests, Cancer,Screen, Anti-Cancer Drug,Screen, Antitumor Drug,Screens, Anti-Cancer Drug,Screens, Antitumor Drug,Test, Cancer Drug,Tests, Cancer Drug,Tumor Specific Drug Screening Tests
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man