Quercetin blocks t-AUCB-induced autophagy by Hsp27 and Atg7 inhibition in glioblastoma cells in vitro

J Neurooncol. 2016 Aug;129(1):39-45. doi: 10.1007/s11060-016-2149-2. Epub 2016 May 12.

Abstract

We previously demonstrated that the acquired resistance because of Hsp27 activation weakens the cytotoxic effect of t-AUCB on glioblastoma cells. Since autophagy is regarded as a survival mechanism for cells exposed to cytotoxic agents, the aim of this study is to investigate whether t-AUCB induces autophagy and whether Hsp27 and autophagy are interacted with each other. Our data demonstrated that t-AUCB induces autophagy in glioblastoma cells and regulates multiple autophagy related-gene expression. t-AUCB induces overexpression of Atg7, which is downstream of Hsp27 and participates in the resistance of glioblastoma cells to t-AUCB treatment. Hsp27 inhibitor quercetin suppresses Atg7 expression and strengthens t-AUCB-induced cell death by autophagy blockage. We concluded that combination of quercetin and t-AUCB might be a potential strategy for glioblastoma treatment.

Keywords: Autophagy; Glioma; Heat shock protein 27; Quercetin; Soluble epoxide hydrolase inhibitor.

MeSH terms

  • Antineoplastic Agents / administration & dosage*
  • Antineoplastic Agents / therapeutic use
  • Autophagy / drug effects*
  • Autophagy-Related Protein 7 / metabolism*
  • Benzoates / administration & dosage*
  • Benzoates / therapeutic use
  • Brain Neoplasms / drug therapy
  • Brain Neoplasms / metabolism*
  • Cell Line, Tumor
  • Gene Expression / drug effects
  • Glioblastoma / drug therapy
  • Glioblastoma / metabolism*
  • HSP27 Heat-Shock Proteins / metabolism*
  • Heat-Shock Proteins
  • Humans
  • In Vitro Techniques
  • Molecular Chaperones
  • Quercetin / administration & dosage*
  • Quercetin / therapeutic use
  • Urea / administration & dosage
  • Urea / analogs & derivatives*
  • Urea / therapeutic use

Substances

  • 4-(4-(3-adamantan-1-ylureido)cyclohexyloxy)benzoic acid
  • Antineoplastic Agents
  • Benzoates
  • HSP27 Heat-Shock Proteins
  • HSPB1 protein, human
  • Heat-Shock Proteins
  • Molecular Chaperones
  • Urea
  • Quercetin
  • ATG7 protein, human
  • Autophagy-Related Protein 7