tcsc3177 SJ-172550

SJ-172550 is a small molecule inhibitor of MDMX; competes for the wild type p53 peptide binding to MDMX with an EC₅₀ of 5 μM.

IC50 & Target: IC50: 5 μM (MDMX)^[1]

In Vitro: The p53 pathway is disrupted in virtually every human tumor. SJ-172550 binds the p53-binding pocket of MDMX, thereby displacing p53. SJ-172550 binds reversibly to MDMX and effectively kills retinoblastoma cells in which the expression of MDMX is amplified. The effect of SJ-172550 is additive when combined with an MDM2 inhibitor nutlin-3a^[1]. SJ-172550 acts through a complicated mechanism in which the compound forms a covalent but reversible complex with MDMX and locks MDMX into a conformation that is unable to bind p53. The relative stability of this complex is influenced by many factors including the reducing potential of the media, the presence of aggregates^[2].