An Embryonic Diapause-like Adaptation with Suppressed Myc Activity Enables Tumor Treatment Persistence

Cancer Cell. 2021 Feb 8;39(2):240-256.e11. doi: 10.1016/j.ccell.2020.12.002. Epub 2021 Jan 7.

Abstract

Treatment-persistent residual tumors impede curative cancer therapy. To understand this cancer cell state we generated models of treatment persistence that simulate the residual tumors. We observe that treatment-persistent tumor cells in organoids, xenografts, and cancer patients adopt a distinct and reversible transcriptional program resembling that of embryonic diapause, a dormant stage of suspended development triggered by stress and associated with suppressed Myc activity and overall biosynthesis. In cancer cells, depleting Myc or inhibiting Brd4, a Myc transcriptional co-activator, attenuates drug cytotoxicity through a dormant diapause-like adaptation with reduced apoptotic priming. Conversely, inducible Myc upregulation enhances acute chemotherapeutic activity. Maintaining residual cells in dormancy after chemotherapy by inhibiting Myc activity or interfering with the diapause-like adaptation by inhibiting cyclin-dependent kinase 9 represent potential therapeutic strategies against chemotherapy-persistent tumor cells. Our study demonstrates that cancer co-opts a mechanism similar to diapause with adaptive inactivation of Myc to persist during treatment.

Keywords: CDK9; CRISPR; MYC; adaptation to stress; breast cancer; cancer; diapause; drug persistence; prostate cancer; residual tumor.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adaptation, Physiological / drug effects
  • Adaptation, Physiological / genetics*
  • Animals
  • Antineoplastic Agents / pharmacology
  • Apoptosis / genetics
  • Cell Line
  • Cell Line, Tumor
  • Cyclin-Dependent Kinase 9 / genetics
  • Diapause / drug effects
  • Diapause / genetics
  • Embryo, Mammalian / drug effects
  • Embryo, Mammalian / physiology*
  • Female
  • HEK293 Cells
  • Humans
  • MCF-7 Cells
  • Mice
  • Proto-Oncogene Proteins c-myc / genetics*
  • Transcription Factors / genetics
  • Transcription, Genetic / genetics
  • Up-Regulation / drug effects
  • Up-Regulation / genetics

Substances

  • Antineoplastic Agents
  • Proto-Oncogene Proteins c-myc
  • Transcription Factors
  • Cyclin-Dependent Kinase 9