HIF-2α/LPCAT1 orchestrates the reprogramming of lipid metabolism in ccRCC by modulating the FBXW7-mediated ubiquitination of ACLY

Int J Biol Sci. 2025 Jan 1;21(2):614-631. doi: 10.7150/ijbs.103032. eCollection 2025.

Abstract

The current research revealed a strong link between lipid reprogramming and dysregulated lipid metabolism to the genesis and development of clear cell renal cell carcinoma (ccRCC). Pathologically, ccRCC exhibits a high concentration of lipid droplets within the cytoplasm. HIF-2α expression has previously been demonstrated to be elevated in ccRCC caused by mutations in the von Hippel-Lindau (VHL) gene, which plays a vital role in the development of renal cell carcinoma. Nevertheless, the mechanisms by which HIF-2α influences lipid metabolism reprogramming are unknown. Our investigation demonstrated that HIF-2α directly binds to the promoter region of LPCAT1, promoting its transcription. RNA-seq and lipidomics mass spectrometry studies showed that knocking down LPCAT1 significantly reduced triglyceride production. Research suggests that KD-LPCAT1 involves activation of the NF-κB signaling pathway, which activates F-Box/WD Repeat-Containing Protein 7 (FBXW7). FBXW7, an E3 ubiquitin ligase involved in lipid metabolism, interacts with ATP Citrate Lyase (ACLY) to promote its degradation, lowering fatty acid production and contributing to the lipid content reduction.

Keywords: FBXW7; HIF-2α; LPCAT1; Lipid Metabolism and Ubiquitination; ccRCC.

MeSH terms

  • ATP Citrate (pro-S)-Lyase / genetics
  • ATP Citrate (pro-S)-Lyase / metabolism
  • Basic Helix-Loop-Helix Transcription Factors* / genetics
  • Basic Helix-Loop-Helix Transcription Factors* / metabolism
  • Carcinoma, Renal Cell* / genetics
  • Carcinoma, Renal Cell* / metabolism
  • Cell Line, Tumor
  • F-Box-WD Repeat-Containing Protein 7* / genetics
  • F-Box-WD Repeat-Containing Protein 7* / metabolism
  • Humans
  • Kidney Neoplasms / genetics
  • Kidney Neoplasms / metabolism
  • Lipid Metabolism* / genetics
  • Signal Transduction
  • Ubiquitination*

Substances

  • F-Box-WD Repeat-Containing Protein 7
  • endothelial PAS domain-containing protein 1
  • Basic Helix-Loop-Helix Transcription Factors
  • ATP Citrate (pro-S)-Lyase
  • FBXW7 protein, human