Abstract ND09: The discovery and characterization of CFT8634: A potent and selective degrader of BRD9 for the treatment of SMARCB1-perturbed cancers

作者：Katrina L. Jackson, Roman V. Agafonov, Mark W. Carlson, Prasoon Chaturvedi, David Cocozziello, Kyle S. Cole, Richard W. Deibler, Scott J. Eron, Andrew C. Good, Ashley Hart, Minsheng He, Christina S. Henderson, Hongwei Huang, Marta Isasa, Ruth Kirby, Linda Lee, Michelle Mahler, Moses Moustakim, Christopher G. Nasveschuk, Michael R. Palmer, Laura L. Poling, Roy M. Pollock, Matthew Schnaderbeck, Stan Spence, Gesine K. Veits, Jeremy L. Yap, Ning Yin, Rhamy Zeid, Adam Crystal, Andrew J. Phillips, Stewart L. Fisher · 发表于：Cancer Research · 年份：2022 · DOI：10.1158/1538-7445.am2022-nd09 · 被引用次数：37 · 研究领域：Chromatin Remodeling and Cancer、Peptidase Inhibition and Analysis、Protein Degradation and Inhibitors

Abstract Introduction: The chromatin factor BRD9 is a genetic dependency in some cancers, often referred to as SMARCB1-perturbed cancers. Two types of genetic alterations result in SMARCB1 perturbation: SS18-SSX gene fusion and SMARCB1 loss-of-function mutations. In synovial sarcoma, a rare and aggressive soft tissue malignancy comprising approximately 10% of all soft tissue sarcomas, the presence of the SS18-SSX fusion gene drives the disruption of SMARCB1 function and leads to a synthetic lethal dependence on BRD9. In SMARCB1-null solid tumors, for example malignant rhabdoid tumors (MRT), poorly differentiated chordomas, and epithelioid sarcomas, the absence of SMARCB1 protein results in a similar BRD9 dependence. Thus, in SMARCB1-perturbed cancers, including synovial sarcoma and SMARCB1-null cancers, degradation of BRD9 is hypothesized to result in an anticancer effect. CFT8634 is an orally bioavailable heterobifunctional degrader that induces ternary complex formation with BRD9 and an E3 ligase, leading to the ubiquitination of BRD9 and its subsequent degradation by the proteasome. Results: Here we describe the chemical structure of CFT8634 and an overview of the medicinal chemistry path leading to its discovery. In vitro, CFT8634 promotes rapid, potent, deep, and selective degradation of BRD9 with a half-maximal degradation concentration (DC50) of 2 nM in a synovial sarcoma cell line. In long-term growth assays, CFT8634 is effective at impairing cell growth in a concentr...