Zafirlukast Induces VHL- and HIF-2α-Dependent Oxidative Cell Death in 786-O Clear Cell Renal Carcinoma Cells

Int J Mol Sci. 2022 Mar 25;23(7):3567. doi: 10.3390/ijms23073567.

Abstract

Mutations in the Von Hippel-Lindau (VHL) gene are the driving force in many forms of clear cell renal cell carcinoma (ccRCC) and promote hypoxia-inducible factor (HIF)-dependent tumor proliferation, metastasis and angiogenesis. Despite the progress that has already been made, ccRCC generally remain resistant to conventional therapies and ccRCC patients suffer from metastasis and acquired resistance, highlighting the need for novel therapeutic options. Cysteinyl leukotriene receptor 1 (CysLTR1) antagonists, like zafirlukast, are administered in bronchial asthma to control eicosanoid signaling. Intriguingly, long-term use of zafirlukast decreases cancer risk and leukotriene receptor antagonists inhibit tumor growth, but the mechanisms still remain unexplored. Therefore, we aim to understand the mechanisms of zafirlukast-mediated cell death in ccRCC cells. We show that zafirlukast induces VHL-dependent and TNFα-independent non-apoptotic and non-necroptotic cell death in ccRCC cells. Cell death triggered by zafirlukast could be rescued with antioxidants and the PARP-1 inhibitor Olaparib, and additionally relies on HIF-2α. Finally, MG-132-mediated proteasome inhibition sensitized VHL wild-type cells to zafirlukast-induced cell death and inhibition of HIF-2α rescued zafirlukast- and MG-132-triggered cell death. Together, these results highlight the importance of VHL, HIF and proteasomal degradation in zafirlukast-induced oxidative cell death with potentially novel therapeutic implications for ccRCC.

Keywords: CysLTR1; Von Hippel–Landau; clear cell renal cell carcinoma; hypoxia-inducible factor-2α.

MeSH terms

  • Basic Helix-Loop-Helix Transcription Factors / metabolism
  • Carcinoma, Renal Cell* / drug therapy
  • Carcinoma, Renal Cell* / genetics
  • Carcinoma, Renal Cell* / pathology
  • Cell Death
  • Cell Line, Tumor
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Indoles
  • Kidney Neoplasms* / drug therapy
  • Kidney Neoplasms* / genetics
  • Kidney Neoplasms* / metabolism
  • Oxidative Stress
  • Phenylcarbamates
  • Sulfonamides
  • Von Hippel-Lindau Tumor Suppressor Protein / genetics
  • Von Hippel-Lindau Tumor Suppressor Protein / metabolism

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Indoles
  • Phenylcarbamates
  • Sulfonamides
  • Von Hippel-Lindau Tumor Suppressor Protein
  • VHL protein, human
  • zafirlukast