Background:

IC50s: 7.2 M/0.93 M for USP7/USP8, respectively.

DUBs-IN-2 is a potent deubiquitinase enzyme inhibitor.

USP7 (or HAUSP) associated with the protein Mdm2 (an E3 ubiquitin ligase) recognizes the N-terminal transactivation domain of the p53 tumor suppressor and elicites its degradation by ubiquitination. USP7 also interacts with directly essential viral proteins (p53, FOXO4, PTEN) and oncogenic pathways. In addition, phenotypes connected with USP7 silencing strongly reveal that targeting USP7 by small-molecule inhibitors may be an potential direction for antiviral and anticancer therapies. USP8 (or UBPY) interacts with many substrates, such as the epidermal growth factor receptor (EGFR), an essential for the regulating cell survival, proliferation, and differentiation pathways), and is a critical regulator of receptor endocytosis and trafficking [1].

In vitro: Human USP7 and USP8 enzymes in baculovirus-infected insect cells were overexpressed in their full-length forms, then purified by the His-tag affinity chromatography procedure. using ubiquitin C-terminal 7-amido-4-methylcoumarin (Ub–AMC) evaluates inhibition of USP7 and USP8 deubiquitinating activity. Ub–AMC is hydrolyzed by deubiquitinating enzymes, thus releasing AMC. IC50 values were calculated based on dose–response curve after dilution of this compound in eight final concentrations, ranging from 100 mm to 10 nm [1].

DUBs-IN-2 as potent inhibitors of USP7 and USP8 deubiquitinating enzymes was identified functionalized cyanopyrazines by high-throughput screening of 65092 chemically diverse compounds for activity toward full-length USP7 cysteine protease in a fluorescence-based biochemical assay [1].

In vivo: So far, no study in vivo has been conducted.

Clinical trial: So far, no clinical study has been conducted.

Reference:
[1] Colombo M, Vallese S, Peretto I, Jacq X, Rain JC, Colland F, Guedat P.? Synthesis and biological evaluation of 9-oxo-9H-indeno[1,2-b]pyrazine-2,3-dicarbonitrile analogues as potential inhibitors of deubiquitinating enzymes. ChemMedChem. 2010 Apr 6;5(4):552-8._x000C_