Triptolide-mediated cell death in neuroblastoma occurs by both apoptosis and autophagy pathways and results in inhibition of nuclear factor-kappa B activity

Am J Surg. 2013 Apr;205(4):387-96. doi: 10.1016/j.amjsurg.2013.01.008. Epub 2013 Feb 19.

Abstract

Background: Neuroblastoma is an aggressive pediatric malignancy with significant chemotherapeutic resistance. We assessed triptolide as a potential therapy.

Methods: SH-SY5Y and IMR-32 neuroblastoma cell lines were treated with triptolide. Viability, intracellular calcium, caspase activation, protein, and mRNA levels were measured. Autophagy was evaluated with confocal microscopy. Nuclear factor-kappa B (NF-κB) activation was measured using a dual luciferase assay.

Results: Triptolide treatment resulted in death in both cell lines within 72 hours, with sustained increases in intracellular calcium. IMR-32 cells underwent cell death by apoptosis. Conversely, light chain 3II (LC3II) protein levels were elevated in SH-SY5Y cells, which is consistent with autophagy. Confocal microscopy confirmed increased LC3 puncta in SH-SY5Y cells compared with control cells. Heat shock pathway protein and mRNA levels decreased with treatment. NF-κB assays demonstrated inhibition of tumor necrosis factor (TNF)-α-induced activity with triptolide.

Conclusions: Triptolide treatment induces cell death in neuroblastoma by different mechanisms with multiple pathways targeted. Triptolide may serve a potential chemotherapeutic role in advanced cases of neuroblastoma.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Antineoplastic Agents, Alkylating / pharmacology
  • Antineoplastic Agents, Alkylating / therapeutic use*
  • Apoptosis / drug effects*
  • Autophagy / drug effects*
  • Biomarkers, Tumor / antagonists & inhibitors*
  • Biomarkers, Tumor / metabolism
  • Blotting, Western
  • Calcium / metabolism
  • Caspase 3 / metabolism
  • Caspase 7 / metabolism
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Diterpenes / pharmacology
  • Diterpenes / therapeutic use*
  • Dose-Response Relationship, Drug
  • Epoxy Compounds / pharmacology
  • Epoxy Compounds / therapeutic use
  • Fluorescent Antibody Technique
  • Heat-Shock Proteins / metabolism
  • Humans
  • Microtubule-Associated Proteins / metabolism
  • NF-kappa B / antagonists & inhibitors*
  • Neuroblastoma / drug therapy*
  • Neuroblastoma / metabolism
  • Phenanthrenes / pharmacology
  • Phenanthrenes / therapeutic use*
  • Real-Time Polymerase Chain Reaction

Substances

  • Antineoplastic Agents, Alkylating
  • Biomarkers, Tumor
  • Diterpenes
  • Epoxy Compounds
  • Heat-Shock Proteins
  • Microtubule-Associated Proteins
  • NF-kappa B
  • Phenanthrenes
  • light chain 3, human
  • triptolide
  • Caspase 3
  • Caspase 7
  • Calcium