MicroRNA-324-5p-CUEDC2 Axis Mediates Gain-of-Function Mutant p53-Driven Cancer Stemness

Mol Cancer Res. 2021 Oct;19(10):1635-1650. doi: 10.1158/1541-7786.MCR-20-0717. Epub 2021 Jul 13.


Regulation of cancer stemness has recently emerged as a new gain-of-function (GOF) property of mutant p53. In this study, we identify miR-324-5p as a critical epigenetic regulator of cancer stemness and demonstrate its role in mediating GOF-mutant p53-driven stemness phenotypes. We report that miR-324-5p is upregulated in human cancer cell lines and non-small cell lung carcinoma (NSCLC) tumors carrying TP53 GOF mutations. Mechanistically, we show that GOF mutant p53 upregulates miR-324-5p expression via c-Myc, an oncogenic transcription factor in cancer cells. Our experimental results suggest that miR-324-5p-induced CSC phenotypes stem from the downregulation of CUEDC2, a downstream target gene of miR-324-5p. Accordingly, CUEDC2 complementation diminishes elevated CSC marker expression in miR-324-5p-overexpressing cancer cells. We further demonstrate that mutant p53 cancer cells maintain a low level of CUEDC2 that is rescued upon miR-324-5p inhibition. Importantly, we identify CUEDC2 downregulation as a novel characteristic feature of TP53-mutated human cancers. We show that activation of NF-κB due to downregulation of CUEDC2 by miR-324-5p imparts stemness in GOF mutant p53 cancer cells. Finally, we provide evidence that TP53 mutations coupled with high miR-324-5p expression predict poor prognosis in patients with lung adenocarcinoma. Thus, our study delineates an altered miR-324-5p-CUEDC2-NF-κB pathway as a novel regulator of GOF mutant p53-driven cancer stemness. IMPLICATIONS: Our findings implicate miRNA-324-5p as a novel epigenetic modifier of human cancer stemness.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics*
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Cell Line, Tumor
  • Cell Movement / genetics
  • Cell Proliferation / genetics
  • Down-Regulation / genetics
  • Gain of Function Mutation / genetics*
  • Gene Expression Regulation, Neoplastic / genetics
  • Humans
  • Lung Neoplasms / genetics
  • MicroRNAs / genetics*
  • NF-kappa B / genetics
  • Neoplastic Stem Cells / pathology*
  • Oncogenes / genetics
  • Signal Transduction / genetics
  • Tumor Suppressor Protein p53 / genetics*


  • Adaptor Proteins, Signal Transducing
  • CUEDC2 protein, human
  • MIRN324 microRNA, human
  • MicroRNAs
  • NF-kappa B
  • TP53 protein, human
  • Tumor Suppressor Protein p53