U2AF65 mediated circPVT1 promotes NSCLC cell proliferation and inhibits ferroptosis through the miR-338-3p/GPX4 axis

Cell Biol Toxicol. 2025 May 14;41(1):84. doi: 10.1007/s10565-025-10028-4.

Abstract

Background: Dysregulation of circRNA expression is associated with increased metastasis and an adverse prognosis in non-small cell lung cancer (NSCLC). Herein, this study assessed the role and regulatory mechanism of circPVT1 in NSCLC development.

Methods: CircPVT1 expression was determined using qPCR. Functional assays, including cell proliferation, colony formation, and ferroptosis-related measurements (ROS, MDA, SOD, GSH and Fe2+ levels), were conducted following circPVT1 knockdown. The interactions between RNA and protein were determined through RIP, dual-luciferase reporter and fluorescence in situ hybridization. Actinomycin D assay was employed to test circPVT1 stability. Additionally, tumor progression in vivo was evaluated in xenograft models with U2AF65 knockdown.

Results: CircPVT1 was significantly elevated in NSCLC samples, correlating with worse clinical outcomes. Its knockdown resulted in diminished cell proliferation and increased ferroptosis. Mechanically, circPVT1 sponges miR-338-3p, facilitating GPX4 expression, which enhanced cell proliferation. U2AF65 bound to and stabilized circPVT1, promoting cell proliferation. In animal models, U2AF65 knockdown suppressed tumor progression by regulating the circPVT1/miR-338-3p/GPX4 signaling pathway.

Conclusions: U2AF65 stabilizes circPVT1 to promote NSCLC advancement through miR-338-3p suppression and GPX4 upregulation. Thus, circPVT1 and U2AF65 may be potential therapeutic targets in NSCLC.

Keywords: CircPVT1; Ferroptosis; GPX4; MiR-338-3p; NSCLC; U2AF65.

MeSH terms

  • Animals
  • Carcinoma, Non-Small-Cell Lung* / genetics
  • Carcinoma, Non-Small-Cell Lung* / metabolism
  • Carcinoma, Non-Small-Cell Lung* / pathology
  • Cell Line, Tumor
  • Cell Proliferation / genetics
  • Female
  • Ferroptosis* / genetics
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Lung Neoplasms* / genetics
  • Lung Neoplasms* / metabolism
  • Lung Neoplasms* / pathology
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • MicroRNAs* / genetics
  • MicroRNAs* / metabolism
  • Phospholipid Hydroperoxide Glutathione Peroxidase* / genetics
  • Phospholipid Hydroperoxide Glutathione Peroxidase* / metabolism
  • RNA, Circular* / genetics
  • RNA, Circular* / metabolism
  • RNA, Long Noncoding* / genetics
  • RNA, Long Noncoding* / metabolism

Substances

  • MicroRNAs
  • RNA, Circular
  • Phospholipid Hydroperoxide Glutathione Peroxidase
  • MIRN338 microRNA, human
  • RNA, Long Noncoding
  • PVT1 long-non-coding RNA, human