Inhibition of NR4A1 promotes ROS accumulation and IL24-dependent growth arrest in rhabdomyosarcoma

Erik Hedrick, Kumaravel Mohankumar, Alexandra Lacey, Stephen Safe

Research output: Contribution to journalArticle

2 Scopus citations

Abstract

Nuclear receptor 4A1 (NR4A1, Nur77) is overexpressed in rhabdomyosarcoma (RMS), and inactivation of NR4A1 (siNR4A1) or treatment with the NR4A1 antagonist 1,1-bis (30-indoly)-1-(p-hydroxy-phenyl)methane (DIM-C-pPhOH) has antiproliferative and proapoptotic effects on RMS cells. However, the mechanism by which NR4A1 inhibition exerts these effects is poorly defined. Here, we report that NR4A1 silencing or inhibition resulted in accumulation of reactive oxygen species (ROS) and ROS-dependent induction of the tumor suppressor-like cytokine IL24 in RMS cells. Mechanistically, NR4A1 was found to regulate the expression of the proreductant genes thioredoxin domain-containing 5 (TXNDC5) and isocitrate dehydrogenase 1 (IDH1), which are downregulated in RMS cells following NR4A1 knockdown or inhibition. Silencing TXNDC5 and IDH1 also induced ROS accumulation and IL24 expression in RMS cells, suggesting that NR4A1 antagonists mediate their antiproliferative and apoptotic effects through modulation of proreductant gene expression. Finally, cotreatment with the antioxidant glutathione or IL24-blocking antibody reversed the effects of NR4A1 inhibition, demonstrating the importance of both ROS and IL24 in mediating the cellular responses.

Original languageEnglish (US)
Pages (from-to)2221-2232
Number of pages12
JournalMolecular Cancer Research
Volume17
Issue number11
DOIs
StatePublished - 2019

ASJC Scopus subject areas

  • Molecular Biology
  • Oncology
  • Cancer Research

Fingerprint Dive into the research topics of 'Inhibition of NR4A1 promotes ROS accumulation and IL24-dependent growth arrest in rhabdomyosarcoma'. Together they form a unique fingerprint.

Cite this