Synthetic hispidin, a PKC inhibitor, is more cytotoxic toward cancer cells than normal cells in vitro

Cell Biol Toxicol. 1997 Mar;13(3):141-53. doi: 10.1023/a:1007321227010.


The trypanocidal activity of naturally occurring 6-(3,4-dihydroxystyryl)-4-hydroxy-2-pyrone (hispidin) prompted us to examine its cytotoxic activity toward normal and cancerous cells in culture. Hispidin synthesized in our laboratory to a high degree of purity (checked by 1H and 13C NMR spectroscopy) was shown to be cytotoxic (between 10(-3) mol/L and 10(-7) mol/L) toward normal human MRC-5 fibroblasts, human cancerous keratinocytes (SCL-1 cell line), and human cancerous pancreatic duct cells (Capan-1 cell line). Interestingly, addition of hispidin in three successive doses (between 10(-5) mol/L and 10(-7) mol/L) led to a 100-fold increase in activity with an enhanced activity on cancer cells compared to normal cells (50%). Synthetic hispidin was found to inhibit isoform beta of protein kinase C (IC50 of 2 x 10(-6) mol/L), but not E. coli and placental type XV alkaline phosphatases. The enhanced activity of hispidin toward the cancerous cell lines is discussed.

Publication types

  • Comparative Study

MeSH terms

  • Adenocarcinoma / drug therapy
  • Adenocarcinoma / pathology
  • Adult
  • Alkaline Phosphatase / antagonists & inhibitors
  • Antineoplastic Agents / pharmacology*
  • Basidiomycota / chemistry
  • Carcinoma, Squamous Cell / drug therapy
  • Carcinoma, Squamous Cell / pathology
  • Cell Line
  • Drug Screening Assays, Antitumor
  • Facial Neoplasms / drug therapy
  • Facial Neoplasms / pathology
  • Fibroblasts / drug effects
  • Growth Inhibitors / pharmacology*
  • Humans
  • Keratinocytes / drug effects
  • Lung / cytology
  • Male
  • Pancreatic Neoplasms / drug therapy
  • Pancreatic Neoplasms / pathology
  • Protein Kinase C / antagonists & inhibitors*
  • Pyrones / chemical synthesis*
  • Pyrones / isolation & purification
  • Pyrones / pharmacology*
  • Tumor Cells, Cultured


  • Antineoplastic Agents
  • Growth Inhibitors
  • Pyrones
  • Protein Kinase C
  • Alkaline Phosphatase
  • hispidin