(1083-B) KRAS PROTAC-mediated degradation and its implication in MAPK pathway activation: SureFire Ultra as a unique technology for measuring downstream effects.

Abstract: The Kirsten rat sarcoma viral oncogene homologue (KRAS) is one of the members of the RAS family and is recognised as one of the hottest targets in oncology being prevalent in pancreatic, colorectal and lung cancer. KRAS transmits signals from receptor tyrosine kinases promoting activation and subsequent phosphorylation of ERK/MAPK pathway. The dysregulation of this activation results in hyperactivation of downstream signalling which leads to uncontrolled cell proliferation and tumour growth. The discovery of potent covalent inhibitors to decrease KRAS activity has been an ongoing challenge among the scientific community. More recently, the use of PROTAC for specific KRAS degradation has become a powerful alternative to effectively diminish downstream activation effects. In addition, the development of specific and highly sensitive methods for measuring KRAS protein inhibition/degradation and subsequent pathway alterations has been challenging. This is mainly due to the lack of specific/high affinity antibodies in the market and the elevated percent of sequence identity among KRAS family members (i.e. NRAS and HRAS).
Herein we have developed a potent, rapid and homogeneous assay using SureFire Ultra technology that effectively measures endogenous KRAS in various cell systems. This new assay in combination with the existing kits in the SureFire Ultra portfolio has allowed us to investigate further the downstream MAPK associated events upon KRAS targeted degradation.
This study highlights once again the effectiveness of Surefire Ultra platform for the detection and characterisation of high-profile oncology targets and demonstrates its utility for downstream pathway analysis.