PRN1371

Kinase experiment:

Enzyme inhibition is determined using a Caliper capillary electrophoresis system that separates phosphorylated and nonphosphorylated peptides on the basis of charge. Different concentrations of PRN1371 are first preincubated with enzyme for 15 min. The reaction is initiated with addition of peptide substrate, ATP, and Mg2+ and incubated at 25°C for 3 h. To stop the reaction, the mixture is quenched with EDTA. The buffer is 100 mM HEPES, pH 7.5, 0.1% BSA, 0.01% Triton X-100, 1 mM DTT, 10 mM MgCl2, 10 mM sodium orthovanadate, 10 μM β-glycerophosphate, and 1% DMSO. The ATP concentration of the reaction is at the predetermined value of the Km for ATP[1].

Cell experiment:

SNU16 cells are first seeded into 384- well plates and PRN1371 added such that the highest final compound concentration is 5 μM. Cells are incubated with PRN1371 for 72 h at 37°C. To detect viability, the Presto-Blue cell viability reagent is added. Plates are read using an Analyst HT with a fluorescent mode employing 530 nm excitation and 590 nm emission[1].

Animal experiment:

Mice: PRN1371 is evaluated in pharmacodynamics and efficacy studies using a SNU16 gastric cancer xenograft mouse model with high overexpression of FGFR2. In nude mice implanted with subcutaneous SNU16 tumors, pFGFR2 levels in the tumor are measured via Western blotting at 8 h following a 10 mg/kg oral dose. Low levels of pFGFR2 confirmed the ability of compound 34 to block FGFR2 activity in tumor tissue. Efficacy is determined by measuring tumor growth inhibition in the same SNU16 xenograft model[1].

References:

[1]. Brameld KA, et al. Discovery of the Irreversible Covalent FGFR Inhibitor 8-(3-(4-Acryloylpiperazin-1-yl)propyl)-6-(2,6-dichloro-3,5-dimethoxyphenyl)-2-(methylamino)pyrido[2,3-d]pyrimidin-7(8H)-one (PRN1371) for the Treatment of Solid Tumors. J Med Chem. 2017 Aug 10;60(15):6516-6527.