OTUB2-IN-1，5MG，SML4050-5MG，Sigma

Biochem/physiol Actions

Inhibits tumor growth by selectively disrupting OTUB2′s activity, thereby reducing PD-L1 levels and enhancing antitumor immunity.
OTUB2-IN-1 selectively targets OTUB2 (OTU deubiquitinase, ubiquitin aldehyde binding 2), a positive regulator of PD-L1, to diminish PD-L1 levels dose-dependently in tumor cells, thereby enhancing antitumor immunity. OTUB2i binds reversibly to OTUB2′s catalytic pocket (KD = 12 µM), selectively impairing its deubiquitinase function without disrupting OTUB2-PD-L1 interactions. OTUB2-IN-1 operates by destabilizing PD-L1 through Lys-48-linked polydeubiquitination leading to a significant reduction in PD-L1-overexpressing tumor growth and enhanced CD8+ CTL-mediated tumor cell elimination, increasing T-cell infiltration in tumors, all achieved without noticeable toxicity. Note: The recommended usage of OTUB2-IN-1 is 10 µM for cellular applications, and for in vivo experiments, it is suggested at 20 mg/kg, administered intraperitoneally (i.p.) in mice. This dosing strategy aims to maximize the inhibitor′s effectiveness in reducing PD-L1 levels in tumor cells while minimizing potential toxicity.