PROTAC ERα Degrader-2 comprises a cIAP1 ligand binding group, a linker and an estrogen receptor α (ERα) binding group. PROTAC ERα Degrader-2 is an ERα degrader. Maximal ERα degradation at 30 μM concentration in human mammary tumor MCF7 cells. Degradation inducers based on cIAP1 are called specific and non-genetic IAP-dependent protein erasers (SNIPERs)[1].
PROTAC ER Degrader-2 serves as a synthesis intermediate for the production of PAC, a compound that incorporates the ADCs linker and PROTACs, which are subsequently conjugated to an antibody. PAC, exhibits a greater capability to degrade estrogen receptor-alpha (ERα) compared to PROTAC (without the presence of an antibody)[1].
PROTAC ER Degrader-3, an intermediate for the synthesis of PAC, specifically compound LP2. PAC serves as the linker for ADCs and PROTACs that are conjugated to an antibody. Notably, when PAC is conjugated to an antibody, it exhibits enhanced degradation of estrogen receptor-alpha (ERα) compared to PROTAC alone [1].
SNIPER(ER)-87 is a chemical compound composed of a derivative of the inhibitor of apoptosis protein (IAP) ligand LCL161 conjugated to the estrogen receptor α (ERα) ligand 4-hydroxytamoxifen using a PEG linker. It effectively degrades the ERα protein with an IC50 value of 0.097 μM. Within cells, SNIPER(ER)-87 selectively recruits XIAP to ERα, and XIAP functions as the primary E3 ubiquitin ligase responsible for the degradation of ERα induced by SNIPER(ER)-87[1][2].