Identification of Celastrol as a Novel YAP-TEAD Inhibitor for Cancer Therapy by High Throughput Screening with Ultrasensitive YAP/TAZ–TEAD Biosensors

The Hippo pathway has emerged as a key signaling pathway that regulates a broad range of biological functions, and dysregulation of the Hippo pathway is a feature of a variety of cancers. Given this, some have suggested that disrupting the interaction of the Hippo core component YAP and its paralog TAZ with transcriptional factor TEAD may be an effective strategy for cancer therapy. However, there are currently no clinically available drugs targeting the YAP/TAZ−TEAD interaction for cancer treatment. To facilitate screens for small molecule compounds that disrupt the YAP−TEAD interaction, we have developed the first ultra-bright NanoLuc biosensor to quantify YAP/TAZ−TEAD protein−protein interaction (PPI) both in living cells and also in vitro using biosensor fusion proteins purified from bacteria. Using this biosensor, we have performed an in vitro high throughput screen (HTS) of small molecule compounds and have identified and validated the drug Celastrol as a novel inhibitor of YAP/TAZ−TEAD interaction. We have also demonstrated that Celastrol can inhibit cancer cell proliferation, transformation, and cell migration. In this study, we describe a new inhibitor of the YAP/TAZ−TEAD interaction warranting further investigation and offer a novel biosensor tool for the discovery of other new Hippo-targeting drugs in future work.