– SA-VA, an intracellular self-assembled PROTAC featuring azide and alkyne groups, selectively degrades VEGFR-2 and EphB4 proteins within U87 cells. This compound undergoes in situ conversion to active PROTAC via a copper-catalyzed click reaction utilizing endogenous copper present in tumor tissues. Additionally, SA-VA induces apoptosis and arrests cell cycle progression in the S phase [1].