CDK9/Cyclin T (IC50 = 10 nM); CDK5/p35 (IC50 = 13 nM); cdk2/cyclin A (IC50 = 47 nM); Cdk4/cyclin D1 (IC50 = 100 nM); cdk6/cyclin D3 (IC50 = 170 nM); Cdk1/cyclin B (IC50 = 210 nM); CDK7/Cyclin H/MAT1 (IC50 = 2400 nM); GSK3β (IC50 = 89 nM)

In the HCT116 and HT29 colon cancer xenograft models, tumor regression is observed for both early-stage and advanced-stage s.c. tumors when AT7519 (9.1 mg/kg) is administered twice daily. (Source: ) In the human MM xenograft mouse model, treatment with AT7519 (15 mg/kg) inhibits tumor growth and increases the median overall survival of the mice in correlation with increased caspase 3 activation.[2]

Kinase assays using radiometric filter binding are conducted for CDK1, CDK2, and GSK3-β. The format of the assays is ELISA for CDKs 4 and 6, and DELFIA for CDK 5. The relevant CDK and 0.12 μg/mL Histone H1 are incubated for 2 or 4 hours, respectively, in 20 mM MOPS, pH 7.2, 25 mM β-glycerophosphate, 5 mM EDTA, 15 mM MgCl2, 1 mM sodium orthovanadate, 1 mM DTT, 0.1 mg/mL BSA, 45 μM ATP (0.78 Ci/mmol), and various concentrations of AT7519. In order to test GSK3-β, the appropriate enzyme and 5 μM glycogen synthase peptide 2 are added, and the mixture is incubated for three hours at 10 mM MOPS pH 7.0, 0.1 mg/mL BSA, 0.001% Brij-35, 0.5% glycerol, 0.2 mM EDTA, 10 mM MgCl2, 0.01% β-mercaptoethanol, 15 μM ATP (2.31 Ci/mmol), all of which are tested. Millipore MAPH filter plates are used to filter the assay reactions after an excess of orthophosphoric acid is added to stop the reaction. After that, the plates are cleaned, scintillant is added, and radioactivity is determined using a Packard TopCount scintillation counting device. For a duration of 30 minutes, CDK5, CDK5/p35, 1μM of a biotinylated Histone H1 peptide (Biotin-PKTPKKAKKL), pH 7.5, 25 mM Tris-HCl, 0.025% Brij-35, 0.1 mg/mL BSA, 1 mM DTT, 15 μM ATP, and various concentrations of AT7519 are incubated. Time-resolved fluorescence at λex=335nm, λem=620nm is used to stop the assay reactions using EDTA, transfer the mixture to Neutravidin-coated plates, and quantify the phosphorylated peptide using a rabbit phospho-cdk1 substrate polyclonal antibody and DELFIA europium-labelled anti-rabbit IgG secondary antibody. Plates are coated with GST-pRb769-921 and blocked with Superblock for the CDK 4 and 6 assays. In order to initiate the reaction, ATP is added to CDK4 or 6. The incubation conditions include 15 mM MgCl2, 50 mM HEPES, pH 7.4, 1 mM DTT, 1 mM EGTA, pH 8.0, 0.02% Triton X-100, 2.5% DMSO, and various concentrations of AT7519. Reactions are halted by adding 0.5 M EDTA pH 8.0 after 30 minutes. After that, plates are cleaned and incubated for one hour with a secondary antibody (alkaline phosphatase linked anti-rabbit) and another hour with the primary antibody (anti-p-Rb Serine 780) diluted in Superblock. Fluorescence is measured on a Spectramax Gemini plate reader at excitation of 450 nm and emission of 580 nm after plates are developed using the Attophos system. Using GraphPad Prism software, IC50 values are computed from replicate curves in every scenario.

The assessable effects of AT7519 on the viability of primary MM cells, MM cell lines, and PBMNCs are determined by measuring the dye absorbance of 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrasodium bromide (MTT). The assay for measuring DNA synthesis uses tritiated thymidine uptake (3H-TdR). 3H-TdR incorporation is measured after MM cells (2–3 × 10⁴ cells/well) are cultured for 24 or 48 hours at 37°C in 96-well culture plates with media and varying concentrations of AT7519 and/or recombinant IL-6 (10 ng/mL) or IGF-1 (50 ng/mL).

[1]. Mol Cancer Ther . 2009 Feb;8(2):324-32.

[2]. Oncogene . 2010 Apr 22;29(16):2325-36.

C16H18CL3N5O2

418.71

417.052608

C, 45.90; H, 4.33; Cl, 25.40; N, 16.73; O, 7.64

902135-91-5

AT7519;844442-38-2;AT7519 TFA;1431697-85-6

white solid powder

C1CNCCC1NC(=O)C2=C(C=NN2)NC(=O)C3=C(C=CC=C3Cl)Cl.Cl

PAOFPNGYBWGKCO-UHFFFAOYSA-N

InChI=1S/C16H17Cl2N5O2.ClH/c17-10-2-1-3-11(18)13(10)15(24)22-12-8-20-23-14(12)16(25)21-9-4-6-19-7-5-9;/h1-3,8-9,19H,4-7H2,(H,20,23)(H,21,25)(H,22,24);1H

4-[(2,6-dichlorobenzoyl)amino]-N-piperidin-4-yl-1H-pyrazole-5-carboxamide;hydrochloride

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)