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].
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].