Cooperative regulation of coupled oncoprotein synthesis and stability in triple-negative breast cancer by EGFR and CDK12/13

Abstract

Evidence has long suggested that epidermal growth factor receptor (EGFR) may play a prominent role in triple-negative breast cancer (TNBC) pathogenesis, but clinical trials of EGFR inhibitors have yielded disappointing results. Using a candidate drug screen, we identified that inhibition of cyclin-dependent kinases 12 and 13 (CDK12/13) dramatically sensitizes diverse models of TNBC to EGFR blockade. This combination therapy drives cell death through the 4E-BP1-dependent suppression of the translation and translation-linked turnover of driver oncoproteins, including MYC. A genome-wide CRISPR/Cas9 screen identified the CCR4-NOT complex as a major determinant of sensitivity to the combination therapy whose loss renders 4E-BP1 unresponsive to drug-induced dephosphorylation, thereby rescuing MYC translational suppression and promoting MYC stability. The central roles of CCR4-NOT and 4E-BP1 in response to the combination therapy were further underscored by the observation of CNOT1 loss and rescue of 4E-BP1 phosphorylation in TNBC cells that naturally evolved therapy resistance. Thus, pharmacological inhibition of CDK12/13 reveals a long-proposed EGFR dependence in TNBC that functions through the cooperative regulation of translation-coupled oncoprotein stability.

Document Details

Document Type
Pub Defense Publication
Publication Date
Sep 11, 2023
Source ID
10.1073/pnas.2221448120

Entities

People

  • Alejandro Barrera
  • Annie Liu
  • Christian G. Cerda-Smith
  • Christopher V. Nicchitta
  • Haley M. Hutchinson
  • Hazel X. Ang
  • Holly Kim
  • Ian C. McDowell
  • Jiaxing Lin
  • Kris C Wood
  • Luke C. Bartelt
  • Natalia Sutiman
  • Qiang Chen
  • Timothy E. Reddy
  • Xinyue L. Deng
  • Zhecheng Sheng

Organizations

  • Agency for Science, Technology and Research
  • Duke Cancer Institute
  • Duke University
  • National Institutes of Health
  • United States Department of Defense

Tags

Fields of Study

  • Biology
  • Medicine

Readers

  • Molecular Biology and Genetics

Technology Areas

  • Biotechnology