Delta-tocotrienol augments cisplatin-induced suppression of non-small cell lung cancer cells via inhibition of the Notch-1 pathway

Anticancer Res. 2012 Jul;32(7):2647-55.

Abstract

Non-small cell lung cancer (NSCLC), accounting for 80% of lung cancers, is the leading cause of all cancer deaths. Previously, we demonstrated that delta-tocotrienol inhibits NSCLC cell proliferation, invasion and induces apoptosis by down-regulation of the Notch-1 signaling pathway. The objective of this study was to investigate whether delta-tocotrienol, could enhance the anticancer effects of cisplatin. Treatment with a combination of delta-tocotrienol and cisplatin resulted in a dose-dependent, significant inhibition of cell growth, migration, invasiveness, and induction of apoptosis in NSCLC cells, as compared to the single agents. This was associated with a decrease in NF-κB DNA binding activity, decrease in Notch-1, Hes-1, Bcl-2 and increase in cleaved Caspase-3 and PARP expressions. These results suggest that down-regulation of Notch-1, via inhibition of NF-κB signaling pathways by delta-tocotrienol and cisplatin, in combination, could provide a potential novel approach for tumor arrest in NSCLC, while lowering the effective dose of cisplatin.

MeSH terms

  • Antineoplastic Combined Chemotherapy Protocols / pharmacology*
  • Apoptosis / drug effects
  • Carcinoma, Non-Small-Cell Lung / drug therapy*
  • Carcinoma, Non-Small-Cell Lung / metabolism
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Cell Growth Processes / drug effects
  • Cell Line, Tumor
  • Cisplatin / administration & dosage
  • Cisplatin / pharmacology*
  • Drug Synergism
  • Humans
  • Lung Neoplasms / drug therapy*
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology
  • Receptor, Notch1 / antagonists & inhibitors*
  • Signal Transduction / drug effects
  • Vitamin E / administration & dosage
  • Vitamin E / analogs & derivatives*
  • Vitamin E / pharmacology

Substances

  • NOTCH1 protein, human
  • Receptor, Notch1
  • Vitamin E
  • tocotrienol, delta
  • Cisplatin