USP7/USP47 inhibitor (USP7/47 inhibitor-1) is a selective ubiquitin-specific protease 7/47 (USP7/USP47) inhibitor, with EC50s of 0.42 μM and 1.0 μM, respectively.

USP7:0.42 Μm(EC50), USP47:1.0 μM(EC50)

USP7/USP47 inhibitor does not inhibit caspase 3, calpain 1, 20S proteasome, and a panel of representative USPs (USP2, USP5, USP8, USP21, and USP28; EC50 > 31.6 μM). USP7/USP47 inhibitor inhibits the growth of HCT-116 cells with an EC50 of 7.6 μM.

The cloning, expression and purification of USP21 from BL21 (DE3) bacteria are performed using standard molecular biology techniques. USP2, USP5, USP7, USP8, USP28, USP47, Ub-PLA2 (Ub-CHOP) and Ub-EKL (Ub-CHOP2) are generated. Caspase 3 and the caspase 3 substrate DEVD-Rh110 are used. Deubiquitylating enzyme, cathepsin B and 20S proteasome chymotrypsin like protease activities are measured. Caspase 3 activity is determined using a similar protocol. Briefly, dose ranges of compound (including USP7/USP47 inhibitor) are incubated with caspase 3 for 30 minutes before the addition of DEVD-Rh110 and reading on a fluorometric plate reader using excitation and emission maxima of 485 nm and 531 nm respectively. The final concentrations of caspase 3 and DEVD-Rh110 are 2 nM and 100 nM respectively