1. Degradation of CCNK/CDK12 is a druggable vulnerability of colorectal cancer
- Author
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Martin Lange, Erik Schulz, Mario Huerta, Mona Blatter, Ali Nowrouzi, Bernhard Kuster, Ulrike Uhrig, Karin Laaber, Axel Benner, Hanno Glimm, Claudia R. Ball, Sina Kreth, Dominik Mumberg, Kerstin Putzker, Friederike Herbst, Joerg Weiske, Hannes Hahne, Sarah Johannes, Gerhard Siemeister, Frank Westermann, Andrea Haegebarth, Martina K. Zowada, Gabriele Stoehr, Simon Holton, Paula L Codo, Joe Lewis, Sebastian M. Dieter, Ulrike Scheib, Lena-Marit Toepper, Sylvia Martin, Christine Siegl, and Anna L. Ostermann-Parucha
- Subjects
Proteomics ,Proteasome Endopeptidase Complex ,Colorectal cancer ,Ubiquitin-Protein Ligases ,Proteolysis ,Druggability ,Antineoplastic Agents ,Apoptosis ,General Biochemistry, Genetics and Molecular Biology ,Ubiquitin ,Cell Line, Tumor ,Cyclins ,Spheroids, Cellular ,Humans ,Medicine ,Cell Self Renewal ,Cell Proliferation ,Cyclin ,medicine.diagnostic_test ,biology ,business.industry ,Ubiquitination ,Cancer ,medicine.disease ,Cyclin-Dependent Kinases ,High-Throughput Screening Assays ,ddc ,Toxicity ,Cancer research ,biology.protein ,Female ,Tumor Suppressor Protein p53 ,Colorectal Neoplasms ,business ,DNA Damage ,CDK12 - Abstract
Summary Novel treatment options for metastatic colorectal cancer (CRC) are urgently needed to improve patient outcome. Here, we screen a library of non-characterized small molecules against a heterogeneous collection of patient-derived CRC spheroids. By prioritizing compounds with inhibitory activity in a subset of—but not all—spheroid cultures, NCT02 is identified as a candidate with minimal risk of non-specific toxicity. Mechanistically, we show that NCT02 acts as molecular glue that induces ubiquitination of cyclin K (CCNK) and proteasomal degradation of CCNK and its complex partner CDK12. Knockout of CCNK or CDK12 decreases proliferation of CRC cells in vitro and tumor growth in vivo. Interestingly, sensitivity to pharmacological CCNK/CDK12 degradation is associated with TP53 deficiency and consensus molecular subtype 4 in vitro and in patient-derived xenografts. We thus demonstrate the efficacy of targeted CCNK/CDK12 degradation for a CRC subset, highlighting the potential of drug-induced proteolysis for difficult-to-treat types of cancer.
- Published
- 2020