Stability and Degradation-based Proteome Profiling Reveals Cannabidiol as a Promising CDC123-eIF2γ Inhibitor for Colorectal Cancer Therapy

Natural products (NPs) have long been foundational in drug discovery, offering unparalleled molecular diversity and complex mechanisms of action. However, identifying molecular targets for NPs remains a significant challenge. This study introduces stability- and degradation-based proteome profiling (SDPP), which integrates orthogonal principles of thermal stability and degradation activity to enhance target identification precision and expand the NP target landscape, mediating dual regulation of protein stability: extracellularly through small-molecule-binding-induced thermodynamic stabilization and intracellularly via ligand-triggered proteolytic degradation. Using SDPP, cannabidiol (CBD) is identified as a novel protein-protein interaction (PPI) inhibitor targeting the CDC123-eIF2γ complex, leading to sustained activation of the integrated stress response and apoptosis in colorectal cancer (CRC) cells. Disruption of the CDC123-eIF2γ complex by CBD offers a selective therapeutic strategy for CRC. Importantly, CDC123 is recognized as an oncogenic driver in CRC, with elevated expression correlating with poor patient prognosis. These findings establish SDPP as a robust framework for NP target identification and position CBD as a first-in-class natural PPI inhibitor with a promising therapeutic potential.