(1150-C) PROTAC and Molecular Glue Mediated Degradation of Neosubstrates using HiBiT-tagged Cell Lines in a High-Throughput Screening Workflow
Tuesday, February 6, 2024
12:00 PM – 1:00 PM EST
Location: Exhibit Halls AB
Abstract: Targeted protein degradation (TPD) has emerged as a transformative approach in drug discovery, offering a novel strategy to modulate protein levels for therapeutic benefit. Within this paradigm, molecular glues (MG) and proteolysis-targeting chimeras (PROTACs) have gained prominence for their ability to induce the degradation of specific target proteins. However, challenges persist in the design of MGs and PROTACs that leverage CRBN-E3 ligase complex recruitment with regard to maintaining on-target specificity while minimizing off-target degradation, which is an important consideration for safety and tolerability. This abstract explores the critical importance of screening these molecular entities across a panel of neosubstrates to characterize selectivity and off-target degradation induced by MGs and PROTACs. In this study, we leverage a HTS workflow utilizing HiBiT-tagged CRISPR cell lines for screening 16 commercially available compounds including PROTACs and MGs for degradation of six well established neosubstrate targets CK1α, GSPT1, IKZF1, IKZF2, IKZF3, and SALL4. Compounds were incubated with cells for 24 hours and protein abundance and cell viability were measured with Promega’s Nano-Glo HiBiT Lytic Detection System and CellTiter-Glo. Degradation potency curves were compiled for each compound against all targets and were used to evaluate selectivity and off-target activity of these molecules. In conclusion, the rapid and systematic screening of molecular glues and PROTACs for neosubstrate degradation represents a critical need in evaluating pre-clinical safety and efficacy of this promising new class of therapeutics. Our approach which enables identification and optimization of highly specific degraders while also quickly identifying off-target safety liabilities could aid the advancement of new TPD drugs to the clinic.