POU2F2-mediated upregulation of lncRNA PTPRG-AS1 inhibits ferroptosis in breast cancer via miR-376c-3p/SLC7A11 axis

Epigenomics. 2024 Feb;16(4):215-231. doi: 10.2217/epi-2023-0100. Epub 2024 Feb 6.

Abstract

Background: Triple-negative breast cancer (TNBC) is a subtype of BC with high rates of mortality. The mechanism of PTPRG-AS1 in ferroptosis of TNBC was investigated. Methods: Chromatin immunoprecipitation and dual-luciferase reporter assays were used to measure intermolecular relationships. MTT and colony formation assays detected cell viability and proliferation. Kits detected Fe2+ and reactive oxygen species levels. The role of PTPRG-AS1 in tumor growth was analyzed in vivo. Results: PTPRG-AS1 was increased in TNBC tissues and cells. PTPRG-AS1 silencing increased the reduction of glutathione and GPX4, increased Fe2+ and reactive oxygen species in erastin-treated cells and inhibited proliferation. POU2F2 transcriptionally upregulated PTPRG-AS1. PTPRG-AS1 targeted miR-376c-3p to upregulate SLC7A11. PTPRG-AS1 knockdown suppressed tumor growth in vivo. Conclusion: POU2F2 transcriptionally activates PTPRG-AS1 to modulate ferroptosis and proliferation by miR-376c-3p/SLC7A11, promoting TNBC.

Keywords: SLC7A11; breast cancer; ferroptosis; lncRNA PTPRG-AS1.

Plain language summary

Triple-negative breast cancer (TNBC) is a kind of breast cancer with high recurrence and low survival rates. Activation of the ferroptosis pathway can inhibit BC proliferation and distant metastasis. Therefore, identifying effective biomarkers and molecular mechanisms of ferroptosis in TNBC is important for its earlier detection and therapy. PTPRG-AS1 is a new type of lncRNA discovered in recent years that is increased in various diseases and is related to prognosis. In the present study, the authors found that POU2F2 promoted PTPRG-AS1 transcription. PTPRG-AS1 knockdown activated ferroptosis in TNBC and inhibited proliferation. Mechanistically, PTPRG-AS1 targeted miR-376c-3p to upregulate SLC7A11, thereby inhibiting ferroptosis and promoting TNBC development. These results indicate that PTPRG-AS1 is a possible therapeutic target in TNBC.

MeSH terms

  • Amino Acid Transport System y+ / genetics
  • Cell Line, Tumor
  • Cell Proliferation / genetics
  • Ferroptosis* / genetics
  • Gene Expression Regulation, Neoplastic
  • Humans
  • MicroRNAs* / genetics
  • Octamer Transcription Factor-2* / genetics
  • RNA, Long Noncoding* / genetics
  • Reactive Oxygen Species
  • Receptor-Like Protein Tyrosine Phosphatases, Class 5 / genetics
  • Triple Negative Breast Neoplasms* / genetics
  • Triple Negative Breast Neoplasms* / pathology
  • Up-Regulation

Substances

  • Amino Acid Transport System y+
  • MicroRNAs
  • Octamer Transcription Factor-2
  • POU2F2 protein, human
  • PTPRG protein, human
  • Reactive Oxygen Species
  • Receptor-Like Protein Tyrosine Phosphatases, Class 5
  • RNA, Long Noncoding
  • SLC7A11 protein, human
  • MIRN376C microRNA, human