Suppression of the tumorigenic phenotype in human oral squamous cell carcinoma cells by an ethanol extract derived from freeze-dried black raspberries

Nutr Cancer. 2006;54(1):58-68. doi: 10.1207/s15327914nc5401_7.


Despite focused efforts to improve therapy, 5-yr survival rates for persons with advanced-stage oral squamous cell carcinoma (SCC) remain discouragingly low. Clearly, early detection combined with strategies for local intervention, such as chemoprevention prior to SCC development, could dramatically improve clinical outcomes. Previously conducted oral cavity human chemoprevention trials, however, have provided mixed results. Although some therapies showed efficacy, they were often accompanied by either significant toxicities or circulating antiadenoviral antibodies. It is clearly apparent that identification of nontoxic, effective treatments is essential to prevent malignant transformation of oral epithelial dysplasias. This study employed cell lines isolated from human oral SCC tumors to investigate the effects of a freeze-dried black raspberry ethanol extract (RO-ET) on cellular growth characteristics often associated with a transformed phenotype such as sustained proliferation, induction of angiogenesis, and production of high levels of reactive species. Our results demonstrate that RO-ET suppresses cell proliferation without perturbing viability, inhibits translation of the complete angiogenic cytokine vascular endothelial growth factor, suppresses nitric oxide synthase activity, and induces both apoptosis and terminal differentiation. These data imply that RO-ET is a promising candidate for use as a chemopreventive agent in persons with oral epithelial dysplasia.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Carcinoma, Squamous Cell / pathology
  • Carcinoma, Squamous Cell / prevention & control*
  • Caspase 3
  • Caspases / metabolism
  • Cell Division / drug effects
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Chemoprevention
  • Enzyme Activation / drug effects
  • Enzyme Inhibitors / pharmacology
  • Ethanol
  • Food Preservation*
  • Freeze Drying
  • Fruit / chemistry*
  • Gene Expression / drug effects
  • Humans
  • Male
  • Middle Aged
  • Mouth Neoplasms / pathology
  • Mouth Neoplasms / prevention & control*
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Phenotype
  • Phytotherapy
  • Plant Extracts / pharmacology*
  • Rosaceae / chemistry*
  • Transglutaminases / metabolism
  • Vascular Endothelial Growth Factor A / genetics


  • Enzyme Inhibitors
  • Plant Extracts
  • Vascular Endothelial Growth Factor A
  • Ethanol
  • Nitric Oxide Synthase
  • Transglutaminases
  • CASP3 protein, human
  • Caspase 3
  • Caspases