Targeted brachyury degradation disrupts a highly specific autoregulatory program controlling chordoma cell identity.

Abstract

Chordomas are rare spinal tumors addicted to expression of the developmental transcription factor brachyury. In chordomas, brachyury is super-enhancer associated and preferentially downregulated by pharmacologic transcriptional CDK inhibition, leading to cell death. To understand the underlying basis of this sensitivity, we dissect the brachyury transcription regulatory network and compare the consequences of brachyury degradation with transcriptional CDK inhibition. Brachyury defines the chordoma super-enhancer landscape and autoregulates through binding its super-enhancer, and its locus forms a transcriptional condensate. Transcriptional CDK inhibition and brachyury degradation disrupt brachyury autoregulation, leading to loss of its transcriptional condensate and transcriptional program. Compared with transcriptional CDK inhibition, which globally downregulates transcription, leading to cell death, brachyury degradation is much more selective, inducing senescence and sensitizing cells to anti-apoptotic inhibition. These data suggest that brachyury downregulation is a core tenet of transcriptional CDK inhibition and motivates developing strategies to target brachyury and its autoregulatory feedback loop.

• Authors: Hadley E Sheppard, Alessandra Dall'Agnese, Woojun D Park, M Hamza Shamim, Julien Dubrulle, Hannah L Johnson, Fabio Stossi, Patricia Cogswell, Josh Sommer, Joan Levy, Tanaz Sharifnia, Mathias J Wawer, Behnam Nabet, Nathanael S Gray, Paul A Clemons, Stuart L Schreiber, Paul Workman, Richard A Young, Charles Y Lin
• Journal: Cell reports. Medicine (Cell Rep Med) Vol. 2 Issue 1 Pg. 100188 (01 19 2021) ISSN: 2666-3791 [Electronic] United States
• PMID: 33521702 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: © 2020 The Authors.

Chemical References

• Biomarkers, Tumor
• Fetal Proteins
• Histones
• KRT18 protein, human
• Keratin-18
• MCL1 protein, human
• Myeloid Cell Leukemia Sequence 1 Protein
• Neoplasm Proteins
• T-Box Domain Proteins
• Cyclin-Dependent Kinases
• Brachyury protein

Topics

• Base Sequence
• Biomarkers, Tumor (genetics, metabolism)
• Cell Line, Tumor
• Cell Survival
• Chordoma (genetics, metabolism, pathology)
• Cyclin-Dependent Kinases (genetics, metabolism)
• Fetal Proteins (genetics, metabolism)
• Gene Expression Regulation, Neoplastic
• Gene Regulatory Networks
• HEK293 Cells
• Histones (genetics, metabolism)
• Humans
• Keratin-18 (genetics, metabolism)
• Myeloid Cell Leukemia Sequence 1 Protein (genetics, metabolism)
• Neoplasm Proteins (genetics, metabolism)
• Proteolysis
• Signal Transduction
• Spinal Neoplasms (genetics, metabolism, pathology)
• T-Box Domain Proteins (genetics, metabolism)