PP121

Kinase experiment:

Purified kinase domains are incubated with inhibitors (PP121) at 2- or 4-fold dilutions over a concentration range of 50- 0.001 µM or with vehicle (0.1% DMSO) in the presence of 10 µM ATP, 2.5 µCi of γ- 32P-ATP and substrate. Reactions are terminated by spotting onto nitrocellulose or phosphocellulose membranes, depending on the substrate; this membrane is then washed 5-6 times to remove unbound radioactivity and dried. Transferred radioactivity is quantitated by phosphorimaging and IC50 values are calculated by fitting the data to a sigmoidal doseresponse using Prism software[1].

Cell experiment:

Cells grown in 96-well plates are treated with PP121 at 4-fold dilutions (10 µM - 0.040 μM) or vehicle (0.1% DMSO). After 72 h cells are exposed to Resazurin sodium salt (22 µM) and fluorescence is quantified. IC50 values are calculated. For proliferation assays involving single cell counting, non-adherent cells are plated at low density (3–5% confluence) and treated with drug (2.5 µM) or vehicle (0.1% DMSO). Cells are diluted into trypan blue daily and viable cells counted using a hemocytometer[1].

Animal experiment:

Mice: Eca-109 cells are injected into the axillary regions of nude mice (5×106 cells/mouse). When the tumor volumes reach around 200 mm3, the mice are randomly separated to three groups: Untreated control, PP121 (30 mg/kg) and vehicle (10% 1-methyl-2-pyrrolidinone and 90% PEG 300) group. Tumor volumes and the mice body weights are measured every 10 d[2].

References:

[1]. Apsel B, et al. Targeted polypharmacology: discovery of dual inhibitors of tyrosine and phosphoinositide kinases. Nat Chem Biol, 2008, 4(11), 691-699.
[2]. Peng Y, et al. The anti-esophageal cancer cell activity by a novel tyrosine/phosphoinositide kinase inhibitor PP121. Biochem Biophys Res Commun. 2015 Sep 11;465(1):137-44.