Licochalcone A induces apoptosis in KB human oral cancer cells via a caspase-dependent FasL signaling pathway

Oncol Rep. 2014 Feb;31(2):755-62. doi: 10.3892/or.2013.2929. Epub 2013 Dec 16.

Abstract

Licochalcone A (Lico-A) is a natural phenol licorice compound with multiple bioactivities, including anti-inflammatory, anti-microbial, anti-fungal and osteogenesis-inducing properties. In the present study, we investigated the Lico-A-induced apoptotic effects and examined the associated apoptosis pathway in KB human oral cancer cells. Lico-A decreased the number of viable KB oral cancer cells. However, Lico-A did not have an effect on primary normal human oral keratinocytes. In addition, the IC50 value of Lico-A was determined to be ~50 µM following dose-dependent stimulation. KB oral cancer cells stimulated with Lico-A for 24 h showed chromatin condensation by DAPI staining, genomic DNA fragmentation by agarose gel electrophoresis and a gradually increased apoptotic cell population by FACS analysis. These data suggest that Lico-A induces apoptosis in KB oral cancer cells. Additionally, Lico‑A‑induced apoptosis in KB oral cancer cells was mediated by the expression of factor associated suicide ligand (FasL) and activated caspase-8 and -3 and poly(ADP-ribose) polymerase (PARP). Furthermore, in the KB oral cancer cells co-stimulation with a caspase inhibitor (Z-VAD-fmk) and Lico-A significantly abolished the apoptotic phenomena. Our findings demonstrated that Lico‑A-induced apoptosis in KB oral cancer cells involves the extrinsic apoptotic signaling pathway, which involves a caspase-dependent FasL-mediated death receptor pathway. Our data suggest that Lico-A be developed as a chemotherapeutic agent for the management of oral cancer.

MeSH terms

  • Amino Acid Chloromethyl Ketones / pharmacology
  • Apoptosis / drug effects*
  • Caspase 3 / genetics
  • Caspase 8 / genetics
  • Caspase Inhibitors / pharmacology
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Chalcones / pharmacology*
  • Chromatin / drug effects
  • Chromatin / genetics
  • DNA Fragmentation / drug effects
  • Extracellular Signal-Regulated MAP Kinases / antagonists & inhibitors
  • Fas Ligand Protein / metabolism*
  • Flavonoids / pharmacology
  • Humans
  • Imidazoles / pharmacology
  • KB Cells
  • Keratinocytes / drug effects
  • Mouth Neoplasms / drug therapy*
  • Poly(ADP-ribose) Polymerases / genetics
  • Protein Kinase Inhibitors / pharmacology
  • Pyridines / pharmacology
  • Signal Transduction / drug effects
  • p38 Mitogen-Activated Protein Kinases / antagonists & inhibitors

Substances

  • Amino Acid Chloromethyl Ketones
  • Caspase Inhibitors
  • Chalcones
  • Chromatin
  • FASLG protein, human
  • Fas Ligand Protein
  • Flavonoids
  • Imidazoles
  • Protein Kinase Inhibitors
  • Pyridines
  • benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone
  • Poly(ADP-ribose) Polymerases
  • Extracellular Signal-Regulated MAP Kinases
  • p38 Mitogen-Activated Protein Kinases
  • Caspase 3
  • Caspase 8
  • licochalcone A
  • SB 203580
  • 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one