Abstract 2693: Targeting the Hippo-YAP pathway with novel small-molecule inhibitors of the YAP-TEAD transcription activity

Abstract We have discovered and are developing multiple novel small molecule medicines targeting the Hippo-YAP pathway. Consisting of upstream regulatory components, the Hippo core kinase components (MST1/2, MAP4K1-7, and LATS1/2), and the downstream transcriptional machinery (YAP, TAZ, and TEAD), the mammalian Hippo-YAP pathway is involved in the regulation of cell proliferation, survival, and cell migration. It functions normally to control tissue regeneration and homeostasis and limit organ size/shape. Genetic alterations of pathway components have been reported in a variety of human malignancies. YAP activity is also linked to resistance to targeted therapies and cancer relapse. Through high-throughput phenotypic screens, we have identified novel classes of small molecule compounds that inhibit the YAP-TEAD transcription activity. Medicinal chemistry efforts on lead optimization resulted in highly potent inhibitors that block YAP-TEAD transcription activity at single digit nM. The classes of inhibitors that were demonstrated to interact directly with the TEAD transcription factors by thermal shift assay, co-crystal structures, and inhibition of autopalmitoylation of purified recombinant TEAD proteins will be presented. In cell-based assays, these inhibitors block TEAD palmitoylation in cells and selectively inhibit proliferation of NF2-deficient mesothelioma. In vivo, complete growth inhibition of NF2 mutant xenograft tumors can be achieved at doses that are well tolerated in mice without adverse effect on body weight. With the discovery and development of potent TEAD inhibitors, we bring forth a new generation of cancer therapeutics targeting a thus far undruggable pathway that is dysregulated in many cancers and critically associated with targeted therapy resistance. Citation Format: Tracy T. Tang, Andrei W. Konradi, Ying Feng, Xiao Peng, Sofie Qiao, Leonard Post. Targeting the Hippo-YAP pathway with novel small-molecule inhibitors of the YAP-TEAD transcription activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2693.